Note: Descriptions are shown in the official language in which they were submitted.
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FLEXIBLE ELASTOMER ARTICLES AND METHODS OF
MANUFACTURIl+TG
BACKGROUND OF THE INVENTION
[0002] Field of the Invention -- The present invention relates generally to
flexible elastomer articles and methods of making the same in which the
articles contain a moisturizing and/or therapeutic material or materials
incorporated into an elastomer(s) from which the article is made or coated
on the wearer contacting surface of the article, or both. More particnlarly,
the invention relates to, in one aspect, elastomer(s) modified with the
addition of botanical extracts in order to enhance the physical and
thezapeutic properties of articles made from these materials. In a second
aspect, the invention relates to coating surFaces of flexi'ble elastomer
articles to improve skin or mucosa moistmizing properties and donnability
with a non-Aloe vera coating material of a mucinous botanical or
laboratory produced polysaccharide which is fortified by additives known
to protect and restore mammalian skin. A third aspect of the invention
combines the first and second aspects. Flexi-ble elastomer articles include
gloves and other single layer or multi-layer flexible elastomer articles,
e.g.,
catheters, stents, incontinence devices having a sheath or sheath type
construction, condoms, cervical caps, diaphragms, dental dams, elastomer
sheets, balloons for use in medical devices, sheaths or tubes used for
medical devices, and finger cots.
[0003] Disposable gloves are widely used by members of the nledical
community, the scientific community, and the industrial connnunity to
protect the wearer from chemical exposure, mechanical abrasion,
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environmental hazards, biohazard contamination and to prevent
transmission of disease or contaminants. Health care providers frequently
wear disposable gloves while performing surgery or other medical or dental
procedures such as patient examinations; thus, the gloves are often also
referred to as disposable examination gloves or disposable surgical gloves.
The disposable gloves are impermeable to biological fluids, tissues and
solids produced by the body or other contaminants (human or animal)
advantageously protecting the wearer from fomitic (transmission by objects
that harbor pathogenic organisms) transmission of pathogens and disease.
[0004] Also, disposable gloves are worn by individuals who wish to
protect their hands from various chemicals, materials and objects which
may irritate, damage or dry out the users skin and which may be harmful or
potentially harmful if allowed to contact or permeate the dermal barrier.
These gloves may be wom in the occupational setting by scientists,
cleaning service workers, food handlers, law enforcement workers,
beauticians or other workers having special protection needs. Thus,
disposable gloves may also be referred to as protective gloves or industrial
gloves. Also some disposable gloves are considered reusable gloves
because they can be used multiple times prior to disposal. For example,
homemakers may reuse the same pair of household gloves to protect their
hands from harsh cleaning solutions or just while doing dishes. Likewise,
gardeners or plant service workers may reuse gloves when spraying plants
with fungicides or other garden chemicals.
[0005] It is desirable that the gloves (disposable and/or reusable) provide
the necessary protection, are durable, flexible, do not cause irritation or
allergy problems to those in contact with the article, are not tacky, are easy
to don, and are comfortable to wear. Unfortunately, sometimes the
desirable characteristics are not achieved.
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[0006] As is known in the art, disposable gloves (and reusable gloves as
well as other flexible elastomer articles) are thin and flexible and are
manufactured from a variety of polymeric materials herein throughout
referred to as "elastomer(s)" or "elastomer material(s)" or "raw
material(s)". These elastomers may be considered a natural rubber as with
natural rubber latex (NRL) or a synthetic rubber, or a plastic and inelude,
but are not limited to, a synthetic polyisoprene, a chloroprene (including
Neoprene-homopolymer of the conjugated diene chloroprene), a
polyurethane (PU), a polyvinyl chloride (PVC), a styrene butadiene styrene
(SBS), a styrene isoprene styrene (SIS), a silicone, a butadiene
methylmethacrylate, an acrylonitrile, a styrene ethylene butylene styrene
(SEBS), an acrylate-based hydrogel, any other clastomer that can be
suspended into an emulsion, any other elastomer that is suspendable,
soluble or miscible in a solution or plastisol, and combinations thereof.
[00071 As is known in the art, disposable gloves (and reusable gloves) are
manufactured of elastomer(s) as single layer gloves or multi-layer gloves.
A single layer glove has one layer having a single or blended (or mixture
of) elastomer material therein. The one layer has an outer surface (or distal
surface) and an opposite wearer-contacting surface. The wearer-contacting
surface may have a material coated, dusted, sprayed or otherwise adhered
thereon which functions to detackify the article during processing
preventing sticking together in storage and/or to facilitate donning of the
gloves by serving as a donning agent and providing enhanced lubricity on
the wearer contacting surface thereby reducing frictional forces.
[00081 The multi-layer glove has more than one layer. One type of
multi-layer glove is a bilarninar glove, which has two layers, namely a first
layer and a second layer. The two layers are of similar or dissimilar
elastomer(s). The first layer is a substrate layer having an elastomeric
material and a distal surface and the second layer is a layer having a
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wearer-contacting surface. The bilaminar glove is commonly manufactured
to have the thickness and the flexibility of the single layer glove. The
materials used in the flexible disposable gloves or reusable gloves
(collectively "gloves") and other flexible articles are elastomers
compoundable as emulsions, solutions or plastisols wherein the elastomers
are suspendable, soluble or miscible. For example, the materials used in
the second layer of the bilaminar gloves are known in the art. See U.S.
Patent 3,286,011 to Kavalir et al., which discloses a mixture of an
elastomer latex and a latex of a resin dipped on an elastomer latex to form
an adherent elastomer-resin film on the elastomer article.
[0009] Other types of multi-layer gloves may have three or more layers,
with one layer bearing the wearer contacting surface,. and another layer
bearing the distal surface with one or more intervening layers between the
two layers having the wearer contacting surface and distal surface.
Similarly, other flexible elastomer articles may have one or more layers of
elastomer (or mixtures of elastomers) with one layer having the wearer-
contacting surface and the same layer (if a single layer) or another layer
having the distal surface (if a multi-layer article).
[0010] Some known in the art methods of making flexible elastomer
gloves and glove materials are for example, U.S. Patent No. 6,465,591, to
Lee; U.S. Patent No. 6,440,498, to Scholar; U.S. Patent No. 6,423,328, to
Chou; U.S. Patent No. 6,414,083, to Plamthottam; U.S. Patent No.
6,391,409, to Yeh et al.; U.S. Patent No. 6,380,283, to Perella, et al.; U.S.
Patent No. 6,369,154, to Suddaby; U.S. Patent No. 6,347,408, to Yeh; U.S.
Patent No. 6,345,394, to Nakamura, et al.; U.S. Patent No. 6,306,514, to
Weikel, et al.; U.S. Patent No. 6,288,159, to Plamthottam; U.S. Patent No.
6,284,856, to Lee; U.S. Patent No. 6,280,673, to Green, et al.; U.S. Patent
No. 6,274,154, to Chou; U.S. Patent No. 6,254,947, to Schaller; U.S.
Patent No. 6,242,042, to Goldstein, et al.; U.S. Patent No. 6,221,447, to
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Munn, et aL; U.S. Patent No. 6,213,123, to Miller, et al.; U.S. Patent No.
6,121,366, to Sharma; U.S. Patent No. 6,066,697, to Coran, et al.; U.S.
Patent No. 6,031,042, to Lipinslci; U.S. Patent No. 6,019,922, to Hassan, et
al.; U.S. Patent No. 6,017,997, to Snow, et al.; U.S. Patent No. 6,016,570,
to Vande Pol et al.; U.S. Patent No. 6,000,061, to Taneja, et al.; U.S. Patent
No. 5,997,969, to Gardon; U.S. Patent No. 5,993,923, to Lee; U.S. Patent
No. 5,985,955, to Bechara, et al.; U.S. Patent No. 5,974,589, to Pugh et al.;
U.S. Patent No. 5,965,276, to Shlenker, et al.; U.S. Patent No. 5,910,533,
to Ghosal, et al.; U.S. Patent No. 5,900,452, to Plamthottam; U.S. Patent
No. 5,881,387, to Merovitz, et al.; U.S. Patent No. 5,881,386, to Horwege
et al.; U.S. Patent No. 5,877,244, to Hoover, et al.; U.S. Patent No.
5,869,072, to Berry; U.S. Patent No. 5,851,683, to Plamthottam, et al.; U.S.
Patent No. 5,833,915, to Shah; U.S. Patent No. 5,807,941, to Tsuji et al.;
U.S. Patent No. 5,742,943, to Chen; U.S. Patent No. 5,741,885, to Dove;
U.S. Patent No. 5,712,346, to Lee; U.S. Patent No. 5,708,132, to Grimm;
U.S. Patent No. 5,700,585, to Lee; U.S. Patent No. 5,691,446, to Dove;
U.S. Patent No. 5,691,069, to Lee; U.S. Patent No. 5,682,613, to Dinatale;
U.S. Patent No. Re. 35,616, to Tillotson, et al.; U.S. Patent No. 5,651,995,
to Oyama et al.; U.S. Patent No. 5,644,798, to Shah; U.S. Patent No.
5,620,773, to Nash; U.S. Patent No. 5,614,202, to DeFina; U.S. Patent No.
5,612,083, to Haung et al.; U.S. Patent No. 5,601,092, to Miller, et al.; U.S.
Patent No. 5,598,850, to Miller, et al.; U.S. Patent No. 5,570,475, to Nile
et al.; U.S. Patent No. 5,568,657, to Cordova, et al.; U.S. Patent No.
5,483,697, to Fuchs; U.S. Patent No. 5,459,879, to Fuchs; U.S. Patent No.
5,458,936, to Miller, et al.; U.S. Patent No. 5,444,121, to Grennes, et al.;
U.S. Patent No. 5,407,715, to Buddenhagen, et al.; U.S. Patent No.
5,405,690, to Hirakawa; U.S. Patent No. 5,405,666, to Brindle; U.S. Patent
No. 5,395,666, to Brindle; U.S. Patent No. 5,370,915, to Hirakawa; U.S.
Patent No. 5,284,607, to Chen; U.S. Patent No. 5,272,771, to Ansell, et al.;
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U.S. Patent No. 5,215,701, to Gould, et al.; U.S. Patent No. 5,112,900, to
Buddenhagen, et al.; U.S. Patent No. 5,088,125, to Ansell, et al.; U.S.
Patent No. 5,020,162, to Kersten, et al.; U.S. Patent No. 5,014,361, to
Gnay; U.S. Patent No. 5,001,354, to Gould et al.; U.S. Patent No.
4,954,309, to McGlotlilin, et al.; U.S. Patent No. 4,917,850, to Gray; U.S.
Patent No. 4,696,065, to Elenteny; U.S. Patent No. 4,575,476, to Podell, et
al.; U.S. Patent No. 4,548,844, to Podell et al.; U.S. Patent No. 4,499,154,
to James, et al.; U.S. Patent No. 4,482,577, to Goldstein, et al.; U.S. Patent
No. 4,463,156, to MaGary, Jr., et al.; U.S. Patent No. 4,390,492, to Kurtz;
U.S. Patent No. 4,371,988, to Berend; U.S. Patent No. 4,340,348, to Kurtz;
U.S. Patent No. 4,302,852, to Joung; U.S. Patent No. 4,251,574, to Berend;
U.S. Patent No. 4,186,445, to Stager; U.S. Patent No. 4,185,330, to Stager;
U.S. Patent No. 4,070,713, to Stockum; U.S. Patent No. 4,061,709, to
Miller et al.; U.S. Patent No. 3,942,193, to Pugh; U.S. Patent No.
3,933,723, to Grenness; U.S. Patent No. 3,813,695, to Podell, Jr. et al.;
U.S. Patent No. 3,397,265, to H.N. Ansell; U.S. Patent No. 3,286,011, to
Kavalir et al.; U.S. Patent No. 3,225,360, to Keilen, Jr., et al.; U.S. Patent
No. 3,059,241, to OBrien, et al.; U.S. Patent No. 3,025,403, to Belknap, et
al.; U.S. Patent Application Publication No. 2002/0110584, to Chou; U.S.
Patent Application Publication No. 2002/0025335, to Cbou; and U.S.
Patent Application Publication No. 2001/0048937 Al, to Chou; PRC
(Peoples Republic of China) ZL 95 2 22651.0 (Applicant: Gin Bao Shan
entezprises Co. Ltd),
[0011] As is known in the art, the ASTM, (American Society for Testing
and Materials, ASTM Internation:al, West Conshohocken, PA, USA) and
ISO (International Organization for Standardization, Geneva, Switzerland)
provide standard specifications for disposable and rensable gloves. The
standard specifications include performance requirements such as, but not
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limited to, freedom from holes, physical dimensions, physical properties,
and total and/or antigen protein content. The standards include, but are not
limited to, ASTM D 3577-01a~ "Standard Specification for Rubber
Surgical Gloves", ASTM D 3578-01a9 "Standard Specification for Rubber
Examination Gloves", ASTM D 5250-00c`' "Standard Specification for
Poly(vinyl chloride) Gloves for Medical Application" and ASTM D 6319-
00aC3 "Standard Specification for Nitrile Examination Gloves for Medical
Application", ISO 10282:2002(E) "Single-use sterile rubber surgical
gloves-Specification", ISO 11193:2002(E) "Single-use medical
examination gloves-Part 1: Specification for gloves made from rubber latex
or rubber solution", ASTM F 1671-97b "Standard Test Method for
Resistance of Materials Used in Protective Clothing to Penetration by
Blood-Borne Pathogens Using Phi-X174 Bacteriophage Penetration as a
Test System", ASTM D 5151-99 "Standard Test Method for Detection of
Holes in Medical Gloves", ASTM D 6499-00 "Standard Test Method for
The Irmnunological Measurement of Anfiigenic Protein in Natural Rubber
and its Products", ASTM D 412-98a "Standard Test Methods for
Vulcanized Rubber and Thermoplastic Elastomers - Tension", AST1vI D
4679-02 "Standard Specification for Rubber General Purpose, Household
or Beautician Gloves", ASTM D 5712-99 "Standard Test Method for The
Analysis of Aqueous Extractable Protein in Natural Rubber and Its
Products Using the Modified Lowry Method", ASTM D 573-99 "Standard
Test Method for Rubber - Deterioration in an Air Oven", ASTM D 6124-01
"Standard Test Method for Residual Powder on Medical Gloves", ASTM D
6355-98 "Standard Test Method for Human Repeat Insult Patch Testing of
Medical Gloves", and ASTM D 3767-01 "Standard Practice for Rubber -
Measurement of Dimensions".
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[0012] The gold standard elastomer for flexibility and comfort in
disposable medical and industrial gloves (reusable gloves and other flexible
articles) since the turn of the last century has been NRL which is harvested
from the rubber tree Hevea brasiliensis. The NRL is synthesized within the
cytoplasm of the laticifer cell of the rubber tree by a series of enzymes
bathed in a complex milieu of minerals, amino acids, proteins, lipids,
polysaccharides, etc., e.g., collectively referred to herein as "botanical
contents". The liquid NRL harvested from the tree including the
aforementioned botanical contents from the laticifer cells is then
compounded or blended with a variety of processing chemicals. It is this
blended NRL emulsion that is coagulated on the surface of a hand shaped
former (in the case of glove manufacture) by a process known in the art as
"dipping" (other flexible articles may be produced by dipping, molding or
extrusion). Depositing the NRL emulsion evenly on the surface of the
former is accomplished by pre-treating the former with a chemical
anticoagulant (typically calcium nitrate or similar salt). The anticoagulant
is applied to the former by dipping and is then oven dried.
[0013] The result is a fine salt crystal layer over the surface of the
former. The salt layer thickness and composition together with the
emulsion viscosity, NRL particle concentra.tion, and dwell time in the NRL
emulsion tank determine the thickness of the finished glove. This salt
pretreated former then dips into the liquid NRL emulsion tank. The
presence of the anticoagulant on the surface initiates coagulation of the
NRL emulsion. As the former is removed from the NRL dip tank
emulsion, the coagulation is not 100% complete. The non coagulated NRL
begins to flow due to gravitational forces.
[0014] For this reason most machines are designed so the former
immediately begins rotating on an axis parallel to the length of the former
and completes a 90 to 180 degree rotation from the base of the former
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before entering the vulcanization ovens. The former rotation is trying to
manage the unwanted flow of the yet uncoagulated NRL emulsion in order
to minimize thickness variability in the finished product. Poor coordination
of coagulation chemistry, emulsion viscosity, NRL density and rotation
patterns of the formers produces a glove which when blown up shows a
river like pattern where thicker rubber tributaries can be seen migrating
from areas where there was pooled uncoagulated NRL which flowed
randomly before coagulating. This uncontrolled flow produces finished
products with thin and thick spots (non-uniformity of article layer, e.g.,
here the glove layer) which have increased vulnerability to breakage in use,
greater susceptibility to oxidative damage in storage and are cosmetically
less pleasing to the user. Even with optimal coordination of the variables
some flow of the NRL occurs prior to coagulation producing variability of
thickness of the finished product particularly at the finger tips.
[0015] Accordingly if a material could be selected that imparted
thixotropic properties which could minimize this unwanted gravitational
flow of the uncoagulated NRL without compromising the other variables of
the process, an advantageous result of providing. a more consistent
thickness could be achieved with the finished product. The aforementioned
methods of depositing a NRL emulsion on a former and the problem
associated with production of a uniform article layer are also associated
with other elastomers which can be suspended into an emulsion. In
addition to NRL, such elastomers include a synthetic polyisoprene, a
chloroprene, a PU, an acrylonitrile, a butadiene methylmethacrylate, an
SBS, an SIS, an SEBS, a silicone, an acrylate-based hydrogel, any other
elastomer that can be suspended into an emulsion, and mixtures thereof (all
of which are currently commercially available as an emulsion with the
exception of SBS, SIS, SEBS). If said material could be added to other
elastomers, unwanted flow of the uncoagulated, unpolymerized or undried
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emulsions would result in a finished article (e.g. glove or other flex.ible
elastomer article) with a more uniform thickness.
[0016] In 1986, OSHA published the Universal Bloodborne Pathogen
Guideline for the specific purpose of minimizing the risk of the
transmission of infection from patient to employee in the context of
delivering healthcare. AIDS and Hepatitis B were of particular concern.
The wearing of single use disposable gloves was a key part of this
guideline and resultei in an exponential increase in both the frequency and
duration of use of NRL gloves. An unforhuiate consequence was a
significant increase in the incidence of glove allergies (for a discussion of
allergy problems, see, Hamann et al. "Allergies Associated with Medical
Gloves - Manufacturing Issues" (1994) Occupational Dermatoses, Vol. 12,
No. 3, pp. 547-599). Prior to glove users
developing particular life threatening IgE specific antibodies against
antigenic proteins originating from the laticifer cytoplasm of the rubber
tree, a significant proportion of the laticifer cell cytoplasmic contents
persisted in a finished NRL glove.
[0017] In the early nineties, in an effort to reduce the antigenic protein
concentration in NRL gloves, processes were developed to remove or
reduce the NRL botanical contents within the emulsions used to produce
NRL products. Unfortunately, the broad variety of cytoplasmic contents
that were now being removed contained natural botanioal waxes, lipids and
polysacchanides which synergWcally functioned as plasticizers. These
natural plasticizers affected the modulus (sofiness) of the finished product
and allowed for a strong, yet supple glove. A lower modulus product is
preferred by glove users because of its relation to the comfort and fit of the
finished article. This user prefend softness of an NRL glove is
compromised by the removal of the botanical contents and is impossi'ble to
replicate with synthetic elastomers.
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[0018] Furkhermore, the minerals, amino acids, proteins, lipids, waxes,
polysaccharides, together with hundreds of additional unique botanical
molecules (botanical contents) also function as excellent emulsifiers to
assist in the optimal uniform dist.ribution of the NRL particles in a dip tank
making the deposition of a uniform film on the porcelain former easier. In
addition, numerous naturally occurring antioxidants (amino acids, proteins,
etc.) are available in the botanical contents that serve to protect the
vulnerable unsaturated carbon bonds of the NRL by scavenging for free
radicals throughout the useful life of the product. These molecules bloom
to the surface over time and function as competitive inhibitors to the
destruction of the NRI, unsaturated bonds. Oxidized glove surfaces
increase breakage while donning and during use. While removal or
inactivation of the antigenic proteins has been necessary, the disadvantage
has been the simultaneous elimination of the many benefits the remaining
molecules of the botanical extract provide.
[0019] Accordingly if the botanical contents of the laticifer cells could be
replaced in the NRL emulsion by a material without cross reactive
antigenic proteins, the benefits of a more stable dipping emulsion with
improved flow properties would be realized and a finished article with
lower modulus and improved oxidative protection would be restored. If the
material could be chosen which also contained dermatologically
therapeutic components, the finished product would be enhanced.
Furthermore, if the material could be added to synthetic elastomers used to
produce gloves (or other flexible elastomer articles), the physical properties
would have the ability to more closely mimic the preferred attributes of
NRL.
[0020] Flexible elastomer articles, like disposable gloves, are frequently
changed by the wearer during the day between patients or between
procedures or activities. Allergy and irritation potential of a finished glove
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has been exacerbated by common glove manufacturing practices of using
vulcanizing accelerators, antioxidants, cornstarch powder and other
additives as means to speed production, ease donnability, prevent taclciness
and enhance durability during the storage and useful life of the glove. In
addition, since disposable gloves cover the hand, moisture (perspiration) is
trapped beneath the glove, contributing to hand dermatitis. As a result, in
excess of 20% of healthcare providers struggle with an allergic or irritant
contact dermatitis or the IgE mediated latex antigen hypersensitivity (Type
I) thereby malcing these individuals more susceptible to infection.
[0021] Solutions to the taclciness and donning problems are coating the
wearer-contacting surface with a powder, halogenation, or other surface
treatments. (See U.S. Patent No. 4,186,445 and U.S. Patent No. 4,185,330,
both to Stager, and U.S. Patent No. 5,614,202 to DeFina.) Cornstarch is
used because most polymers are intrinsically sticky on their surfaces
causing a blocking affect which makes it difficult to don the glove without
the powder. (Other powders used in the interior of the glove to lubricate
the glove, include, but are not limited to, talcum powder, starch dusting
powder, polyglycolic acid powder, insoluble sodium metaphosphate
powder, magnesium carbonate, oat starch and granular vinyl chloride
polymer.) The powder may provide comfort to the wearer's hand as the
hand moisture builds up within the glove as the glove is used but
conversely may also act to dry, abrade and irritate the user's sldn.
[0022] Although many glove users apply lotions and creams to
moisturize their hands, these emollients frequently are oil-based which
deleteriously affects an NRL glove. Further, these creams and lotions often
contain similar antigenic chemicals and serve to exacerbate the skin
problems.
[0023] It has also been shown that the antigenic proteins bloom to the
surface of the NRL glove (or other flexible article) and migrate into the
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powder particles which then serve as vehicles to carry the antigen. This
has been shown to be most problematic as an aerosolized particle delivered
during breathing to the immunoactive tissue of the nasopharynx and
bronchial tree where sensitization and elicitation of Type I NRL reactions
can be initiated. In addition, glove powders can cause sldn irritation and
exacerbate contact allergies, therefore, the reduction or elimination of glove
powders help glove users maintain a healthy dermal barrier and assure
optimal protection against pathogens and contaminants which is the
intended purpose of the glove.
[0024] The need to eliminate or minimize residual glove powder has led
to the development of various powder removal processes and of alternative
glove coatings. To remove unwanted powders, gloves are sometimes
treated to a chlorination and neutralization process. Although these
processes remove unwanted powder they also halogenate the glove surface
and deleteriously affect the physical properties of the glove by accelerating
the oxidation process by cleaving the unsaturated carbon bonds of the NRL
polyisoprene chain, thus decreasing the shelf life and the soflness of the
glove.
[0025] The chlorination treatment of the glove may be used with or
without the additional coating or lubricant composition treatment (see U.S.
Patent No. 5,742,943 to Chen for use of a lubricant composition post
chlorination, where the lubricant composition has a first and a second
composition, where the first composition comprises an acetylenic diol and
at least one compound selected from the group consisting of an organo-
modified silicone, an amino-modified silicone, and 1-hexadecylpyridinium
chloride monohydrate, and the second composition comprises 1-
hexadecylpyridium chloride monohydrate and at least one compound
selected from the group consisting of an organo-modified silicone, an
amino-modified silicone, and an acetylenic diol).
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[0026] The art has responded to the problems associated with powder by
preparing powderless gloves by the use of alternative lubricants, such as,
polymeric lubricant coatings which are bonded to the tissue-contacting
surface of the glove or are adhered to the elastomer, NRL (natural or
synthetic) or plastic itself. (See, for example, U.S. Patent No. 4,548,844 to
Podell et al. flexible rubber article with an interior lining of hydrophilic
plastic material, preferably a hydrogel plastic material and U.S. Patent No.
3,813,695 to Podell, Jr. et al. flexible glove with inner layer of a
hydrophilic plastic material; U.S. Patent No. 6,019,922 to Hassan et al. dip
coating over an elastomer layer formed of an antiblocldng composition
comprising a polymer/co-polymer (such as an anionic aliphatic polyether
polyurethane, or a co-polymer of vinylidene chloride/methyl acrylate, or
natural rubber polymer), a high density polyethylene particle and a wax
(such as a mixture of carnuba wax/paraffin wax); U. S. Patent No.
5,395,666 to Brindle, use of porous, absorbent microparticles, preferably
silica, added to a binder material having good adhesion to both an
elastomeric substrate and to the microparticles; U.S. Patent No. 5,881,386
to Horwege et al. a polyester polyurethane having a texturizing agent
selected from the group consisting of diatomaceous earth, silica, glass
beads and calcium carbonate, is adhered to a plasticized polyvinyl chloride
resin film; U.S. Patent No. 5,974,589 to Pugh et al. use of high density
substantially linear hydrocarbon polymer, (such as polyethylene,
polypropylene, polymethylene, paraffin, low density polyethylene, or a
mixture thereof) to adhere to the surface of a latex article such as a glove;
U. S. Patent No. 5,570,475 to Nile et al., use of polymers on the hand
contacting surface (such as, copolymers of a vinyl alkyl ether and a maleic
ester or copolymers, of an alkylene and a maleic ester, or of copolymers of
vinyl methyl ether and a maleic ester, or polymers of a butyl half ester of
polyethylene/maleic acid, or a butyl half ester of polystyrene/maleic acid,
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of a partly esterified poly(styrene/maleic acid)) or polymers sold under the
name SCRIPTSETS (available from Monsanto) to form a polymer layer on
a natural or synthetic elastomer surface, with optional use of surfactant
(cetyl pyridinium chloride) treatment, with or without use of silicones.
Others have used different materials to form the glove, e.g., see U.S. Patent
No. 4,061,709 to Miller et al. for silicone rubber gloves.
[0027] Coating the gloves with alternative lubricants (glove coatings)
present challenges because coatings are difficult to apply to a glove with a
dip, spray, spray and tumble (spray/tumble), or soaking process. Because
of the relative hydrophobicity of the surface of most gloves, the coatings
tend to bead and concentrate in dependent areas of the glove resulting in
uneven application of the coating.
[0028] For an example of a spray deposition process to impart an interior
texture to the flexible glove see U.S. Patent No. 6,016,570 to Vande Pol et
al. Others have used multiple layers having a first layer of natural rubber
or polyurethane, chloroprenc, styrene/butadiene copolymer, nitrile latex, a
second layer of natural rubber, polyurethane, poly(acrylamide-acrylic acid,
sodium salt) and polyethyleneoxide, and a third wearer-contacting layer of
acrylic copolymer and flurocarbon telomer resin, or alternatively a first
layer of plastisol polyvinyl chloride (PVC) and coating this with the
aforementioned wearer contacting layer, e.g., see U.S. Patent No.
5,612,083 to Haung et al. Other bilaminar (two-layer) glove processes
include PRC Patent ZL95 2 22651.0 disclosing a powder free process of
manufacturing PVC gloves where a polyvinyl chloride substrate is given a
slip surface treatment in a water base process or in an oil-base process. In
the water base process, a water based silicone oil and catalyst form a film
coating on the PVC substrate. In the oil base process, a polyester having
good water solubility is used for the polyurethane epoxy along with a
CA 02448475 2003-11-07
mixture of methy-ethyl-ketone/isobutyl-ketene and isopropyl alcohol to
form the film coating on the PVC substrate.
[0029] Accordingly if a coating material could be chosen for application
to a glove surface (or other flexl'ble article surface) which produces
acceptable donning attributes without the need for cornstarch as a donning
agent, the transmission of the NRL antigenic protein would be minimized.
If the thixotropic properties of the coating material were such that the
coating functioned more like a liquid biopolymer, it would reduce the
beading and pooling of the coating, and allow a uniform coating to be
applied over all the glove (or other flexible article), and the product would
be improved. If the coating material uniformly distributed could also
simultaneously optimize moisture homeostasis between the glove and
epidermis of the wearer to minimize irritant contact dermatitis from the
extremes of dryness and wetness, a contribution would be made in reducing
the risk of infection of damaged skin. If said uniformly distributed coating
material also partially solubilizes during use and delivers therapeutically
important molecules to mitigate the risks of irritant and contact dermatitis,
the user will benefit from added protection. If the coating material also
functions as a microbicide, an additional important level of protection
could be provided if the glove were to fail and skin exposure to a pathogen
occurred.
100301 Furthermore, if said coating material could be applied to the
surface of synthetic gloves and act as a donning agent by improving
donning without powder, and decrease irritant and allergic contact
dermatitis, and provide a microbicide in the case of glove (or other flexible
article) failure, a contribution will be made. Also, if said coating material
could balance moisture under the surface oi the glove, a further
contribution will be made.
16
CA 02448475 2008-01-07
[0031] U.S. Patent No. 6,274,154 and U.S. Patent No. 6,423,328, both to
Chou, U.S. Patent Application
Publication No. 2001/0048937 Al, U.S. Patent Application Publication No.
2002/0025335 Al, and U.S. Patent Application Publication No.
2002/0110584 Al, all to Chou,
disclose a flexible single layer disposable glove
containing dehydrated Aloe vera on the wearer contacting surface and a
method of manufacturing the glove. The method of manufacturing the
gloves discloses the steps of: forming an NRL glove, turning the glove
inside out, applying an aqueous solution of Aloe vera to the surface facing
out, removing the liquid by a controlled dehydration process with heat
tumble drying of the gloves and/or the use of forced heated air to provide a
partially and preferably full or at least substantial dehydration of the Aloe
vera solution in the gloves, and turning the glove right side out so the
dehydrated coating of Aloe vera contacts the hand of the glove wearer.
[0032] When the gloves are worn, the dehydrated Aloe vera is dissolved
by the moisture from the wearer's hand. Aloe vera is a plant, long looked
to in folk medicine for skin care and has been used in skin care products for
moisturizing the upper layers of the epidermis of the skin. (See U.S. Patent
No. 5,800,818 to Pragnaud et al.) Despite the advantages of using Aloe
vera as a coating material, for glove manufacturers competing in the
international glove industry, the cost of the Aloe vera becomes an
important consideration in competing globally.
[0033] What is needed is a flexible elastomer article, such as a disposable
or reusable glove, having materials incorporated within its elastomer matrix
that serve as a stabilizer, a flow modifier, an emulsifier, a plasticizer, a
humectant, and an antioxidant. As a stabilizer, the material should stabilize
the emulsion of the elastomer(s) by maintaining dispersions of otherwise
imiscible phases and inhibiting physical processes (e.g., sedimentation,
17
CA 02448475 2003-11-07
trapping gas bubbles and the non-uniform dispersion of rubber particles)
within the emulsion of the elastomer(s), allowing for a more uniform film
deposition during the dipping process. Additionally, the material should
function as a flow modifier by providing selected thixotropic properties
that modify the rheology of the elastomer emulsion thereby decreasing
unwanted flow of the emulsion when forming the article. The material
should also serve as an emulsifier by actively reducing surface tension
thereby improving film deposition at the time of dipping. The material
should act as a plasticizer by lowering the modulus of the finished article
resulting in a softer glove (or other article) with retained strength and
improved wearer comfort. The material should act as a humectant by
balancing moisture homeostasis thereby enhancing skin moisturizing
properties, lubricity and donning characteristics of the flexible article. The
material should act as an antioxidant preventing unwanted oxidation during
manufacturing and improving the shelf life of the fmished article by
protecting the vulnerable unsaturated carbon bonds of the elastomer.
[0034] A need exists to provide a flexible elastomer article with
improved shelf life having a wearer contacting surface with improved
moisturizing properties, lubricity and donning characteristics, and which
provides comfort to the wearer.
[0035] A need also exists to provide a more economical method of
fabricating a flexible elastomer article with improved lubricity and donning
characteristics, with improved shelf life and which provides comfort to the
wearer.
[00361 Yet another need exists to provide a flexible elastomer article
utilizing raw materials which yield cost saving to the manufacturer without
compromising the attributes of the finished product and which provide
decreased bioburden in the finished product.
18
CA 02448475 2003-11-07
SUMMARY OF THE INVENTION
[0037] The needs, disadvantages and limitations of the background art
discussed above are overcome by the present invention. The present
invention in one of its aspects provides a flexible elastomer article (herein
also "article" or "flexible article") in which a material, preferably, a
biopolymer additive, most preferably a botanical extract(s), having a
polysaccharide therein, is incorporated into an elastomer matrix of a layer
of the article, preferably the layer having a wearer-contacting surface. The
botanical extract serves as a stabilizer, a flow modifier, an emulsifier, an
antioxidant, a plasticizer, a humectant, a moisture regulator and a
moisturizer. It is an advantage of the present invention that the botanical
extract when added to an elastomer emulsion is characterized by stabilizing
the emulsion of the elastomer(s) by maintaining dispersions of otherwise
imiscible phases and inhibiting physical processes (e.g., sedimentation,
trapping gas bubbles and the non-uniform dispersion of rubber particles)
within the emulsion of the elastomer(s), thereby allowing for a more
uniform film deposition during the dipping process. It is another advantage
that the botanical extract acts as a flow modifier and provides thixotropic
properties that modify the rheology of the elastomer emulsion thereby
decreasing unwanted flow of the emulsion when forming the article. It is
another advantage that the botanical extract functions as an emulsifier that
actively reduces surface tension which improves film deposition at the time
of dipping. It is another advantage that the botanical extract acts as a
plasticizer that lowers the modulus of the finished article resulting in a
softer glove with retained strength and improved wearer comfort. It is
another advantage that the botanical extract acts as an antioxidant that
prevents unwanted oxidation during manufacturing and improves the shelf
life of the finished article by protecting the vulnerable unsaturated carbon
bonds of the elastomer. It is another advantage that the botanical extract
19
CA 02448475 2003-11-07
acts as a humectant which balances moisture homeostasis which enhances
skin moisturizing properties. The botanical extract also serves to enhance
lubricity and donning characteristics of the flexible article.
[00381 Another aspect of the present invention provides a non-Aloe vera
coating material having a polysaccharide therein, that when applied as a
coating of an elastomer article, is characterized by acting as a moisture
regulator whereby adsorption and desorption isotherms of the
polysaccharide optimize moisture homeostasis beneath a glove or other
flexible elastomer article. It is an advantage of the present invention that
the non-Aloe vera coating material when applied as a coating act as a
lubricant to improve user comfort, application, utility and donning
characteristics of the article. It is a another advantage that the non-Aloe
vera coating material when applied as a coating function as a flow modifier
that imparts thixotropic properties of a liquid biopolymer facilitating
uniform distribution of the coating over the entire article delivering
therapeutic molecules to the entire hand or other part of the user's anatomy
to which the flexible article is applied. It is a another advantage of the
present invention that the non-Aloe vera coating material impart a range of
therapeutically relevant physiologic benefits including anti-microbial,
wound healing, anti-inflammatory, analgesic and anti-aging (oxidation
injury) properties.
[0039] In another aspect of the present invention, the article, having the
botanical extract incorporated therein and/or having the non-Aloe vera
coating applied thereon, may be either a single layer flexible elastomer
article or a multi-layer flexible elastomer article. The article may be a
glove, such as a single layer glove, or a multi-layer glove, including a
bilaminar glove. The article may be a catheter, a stent, an incontinence
device having a sheath or sheath type construction, a condom, a cervical
cap, a diaphragm, a dental dam, an elastomer sheet, a balloon for use in a
CA 02448475 2003-11-07
medical device, a sheath or a tube used for a medical device, or a finger
cot.
[0040] Another aspect of the present invention provides a method of
fabricating or making a low cost flexible elastomer article in which a
botanical extract is incorporated into an elastomer emulsion and serves as a
stabilizer, flow modifier, emulsifier, plasticizer, humectant and anti-
oxidant. The botanical extract is compounded with one or more selected
elastomers in an emulsion, solution or plastisol prior to vulcanization,
polymerization, solution evaporation and/or fusing (depending on the
selected elastomer(s)).
[00411 Yet another aspect of the present invention provides a method of
applying, to a wearer-contacting surface of a flexible elastomer article, a
non-Aloe vera coating material having a non-Aloe vera botanical extract,
having a polysaccharide therein. The non-Aloe vera botanical extract
serves as a moisture regulator, a lubricant, a donning agent, a flow
modifier, and imparts a range of therapeutic benefits and comfort to the
wearer. The non-Aloe vera botanical extract is applied post vulcanization,
post polymerization, post evaporation of solution or post fusing.
[0042] For the aforementioned aspects of the present invention, the
botanical extract has a polysaccharide therein. The polysaccharide may be
derived from a natural plant material having a mucinous plant (or
botanical) polysaccharide(s), andlor a laboratory produced polysaccharide.
Botanical extracts derived from natural plant materials include one or more
extracts of Aloe vera, Nopal, okra, kelp, tamarind, psyllium, carrageenan,
chia, flax, carob, guar, xanthan, konjac, cassia, tara, karaya, ghatti,
glucomannan, galactomannan or tragacanth.
[0043] The botanical extract is incorporated within the elastomer layer of
the aforementioned flexible article. Preferably the botanical extract is
21
CA 02448475 2003-11-07
incorporated within the elastomer layer forming the wearer-contacting
surface.
[0044] The non-Aloe vera botanical extract includes a non-Aloe vera
plant material having a mucinous plant (or botanical) polysaccharide and/or
a non-Aloe vera laboratory produced polysaccharide. Non-Aloe vera
botanical extracts are derived from non-Aloe vera plant materials and
include one or more of an extract of Nopal, okra, kelp, tamarind, psyllium,
carrageenan, chia, flax, carob, guar, xanthan, konjac, cassia, tara, karaya,
ghatti, tragacanth, glucomannan, galactomannan, or a non-Aloe vera
laboratory produced polysaccharide.
[0045] Finally, it is an objective that all of the aforesaid advantages be
achieved without incurring any substantial relative disadvantage and with
achieving cost savings.
[0046] Other advantages and features of the invention, together with the
organization and manner of operation thereof, will become apparent from
the following detailed description when taken in conjunction with the
accompanying drawings wherein like elements have like numerals
throughout the drawings. It is expressly understood that the drawings are
for the purpose of illustration and description only, and are not intended as
a definition of the limits of the invention.
22
CA 02448475 2003-11-07
DESCRIPTION OF THE DRAWqNGS
[0047] These and other advantages of the present invention are best
understood with reference to the drawings, in which:
[0048] FIG. 1 is a perspective view of a glove showing an outer surface
thereof and an inner or wearer contacting surface thereof;
[0049] FIG. 2 is a cross sectional view of a portion of a single layer glove
in which the material that the glove is made from includes at least one
botanical extract;
[0050] FIG. 3 is a cross sectional view of a portion of a bilaminar glove
in which the material that the interior layer of the glove is made from
includes at least one botanical extract;
[0051] FIG. 4 is a cross sectional view of a portion of a multi-layer glove
in which the material that the innermost layer of the glove is made from
includes at least one botanical extract;
[0052] FIG. 5 is a cross sectional view of a portion of a single layer glove
with an interior surface coating;
[0053] FIG. 6 is a cross sectional view of a portion of a bilaminar glove
with an interior surface coating;
[0054] FIG. 7 is a cross sectional view of a portion of a multi-layer glove
with an interior surface coating;
[0055] FIG. 8 is a cross sectional view of a portion of a single layer glove
with an interior surface coating and in which the material that the glove is
made from includes at least one botanical extract;
100561 FIG. 9 is a cross sectional view of a portion of a bilaminar glove
with an interior surface coating and in which the material that the interior
layer of the glove is made from includes at least one botanical extract;
[0057] FIG. 10 is a cross sectional view of a portion of a multi-layer
glove with an interior surface coating and in which the materials that two
layers of the glove are made from includes at least one botanical extract;
23
CA 02448475 2003-11-07
100581 FIG. 11 is a schematic flow diagram showing a process for
making a flexible elastomer article of the present invention;
[0059] FIG. 12 is a schematic flow diagram showing a process for
coating a flexible elastomer article with a non-Aloe vera coating material of
the present invention;
100601 FIG. 13 is a schematic flow diagram showing a dipping process
for maldng a glove of the present invention;
[0061] FIG. 14 is a schematic flow diagram showing a dipping process
for on-line polymer coating of gloves followed by off line
washing/chlorination;
[0062] FIG. 15 is a schematic flow diagram showing a process following
the dipping operation of FIG. 14;
[0063] FIG. 16 is a schematic flow diagram showing a dipping process
for a powder free coagulant system coupled with on-line polymer coating
of gloves;
[0064] FIG. 17 is a schematic flow diagram showing a dipping process
for on-line chlorination of gloves followed by off-line
washing/chlorination;
[0065] FIG. 18 is a schematic flow diagram showing a process following
the dipping operation of FIG. 17;
[0066] FIG. 19 is a schematic flow diagram showing a dipping process
for a powder free coagulant system coupled with on-line chlorination of
gloves;
[0067] FIG. 20 is a schematic flow diagram showing a method of making
a glove of the present invention;
[0068] FIG. 21 is a schematic flow diagram showing a method of coating
a glove of the present invention;
24
CA 02448475 2003-11-07
[0069] FIG. 22 is a cross section view of a portion of a multi-layer glove
in which the material that a layer of the glove is made from includes at
least one botanical extract;
[0070] FIG. 23 is a cross section view of a portion of a multi-layer glove
with an interior surface coating and with the material that a layer of the
glove is made from including at least one botanical extract;
100711 FIG. 24 is a view of a prior art load tester for measuring donning-
force of a glove;
[0072] FIG. 25 is a water sorption isotherm overlay comparing
adsorption isotherms of materials;
[0073] FIG. 26 is a water sorption isotherm of a Nopal extract;
[0074] FIG. 27 is a water adsorption isotherm of an Aloe vera extract;
[0075] FIG. 28 is a water sorption isotherm of cornstarch;
[0076] FIG. 29 is a water sorption isotherm of silicone powder;
[0077] FIG. 30 is a water sorption isotherm of a polyurethane coating
material; and
100781 FIG. 31 is a comparison of water sorption isotherms of a vinyl
glove coated with a Nopal extract and vitamin E and of a vinyl glove
coated with an Aloe vera extract and Vitamin E.
CA 02448475 2003-11-07
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
100791 This invention relates to the flexible elastomer articles and
methods of making the same. More particularly, the present invention
discloses two aspects which may be used in the manufacture of flexible
elastomer articles, either separately or preferably, together (to form a third
aspect). In a first aspect, the present invention discloses a material,
preferably a biopolymer additive, most preferably a botanical extract(s)
incorporated into an elastomer(s) emulsion, solution and/or plastisol in
order to enhance the physical and therapeutic properties of a flexible
elastomer article made from the elastomer(s) emulsions, solutions, and/or
plastisol. In the second aspect, the invention relates to coating surfaces of
a
flexible elastomer article with a non-Aloe vera coating material which is
fortified by additives known to protect, restore and moisturize mammalian
skin or mucosa and to enhance ease of application or donnability of the
article. A third aspect combines the first and second aspects of the present
invention to produce an article having the botanical extract(s) incorporated
into one or more layers of the article and having the non-Aloe vera coating
material of the present invention on a surface of the article.
(0080] A flexible elastomer article (herein also "article" or "articles" or
"flexible articles" or "flexible article" or flexible (articles)) of the
present
invention has at least one layer of an elastomer or blend (mixture) of
elastomers therein. The article has a wearer contacting surface and an
opposite distal surface. The distal surface is disposed as the most opposite
surface to the wearer contacting surface. (The distal surface is disposed
distal to the wearer contacting surface.) In some instances for certain
articles, the distal surface is referred to as the outer surface or outer
distal
surface. However, for some articles, such as catheters, the distal surface
may be the innermost surface.
26
CA 02448475 2003-11-07
[0081] The flexible article(s) of the present invention include, but are not
limited to, a glove (reusable or disposable), a catheter, a stent or an
incontinence device having a sheath or sheath type construction, a condom,
a cervical cap, a diaphragm, a dental dam, an elastomer sheet, a sheath or
tube for use with a medical device, a finger cot, or a balloon for use in a
medical device (such as, but not limited to, a balloon used with a balloon
catheter, a urinary catheter, a rectal catheter, an endotracheal tube, a
feeding tube, or a cardiac catheter).
[0082] The flexible articles of the present invention are made from one or
more elastomers (hereinalso "elastomer", "elastomers", "elastomer(s)", or
"selected elastomer").
[0083] The botanical extract (hereinalso "botanical extract(s)" or
"botanical extract") has a polysaccharide therein and is derived from a
plant and/or is a laboratory produced polysaccharide. The botanical extract
whether plant derived or laboratory produced share certain properties
which will be discussed later. Suitable examples of botanical extracts of
the present invention include extracts of the following materials: Nopal
and/or Aloe vera, and/or kelp, and/or okra, and/or tamarind, and/or
psyllium, andlor carrageenan, andlor chia, andlor flax, and/or carob, and/or
guar, and/or xanthan, and/or konjac, and/or cassia, and/or tara, and/or
karaya, and/or ghatti, and/or tragacanth, and/or glucomannan, and/or
galactomannan, and/or a laboratory produced polysaccharide. The
aforementioned botanical extracts may be combined or used individually in
the present invention. The botanical extract may be referred to as a
"mucilage" or a "gum" or a "mucinous polysaccharide". The botanical
extract may exist commercially as an extract, a powder, a gel, or in other
ways known in the industry.
[00841 In the first aspect, an elastomer raw material, e.g., an elastomer
emulsion, solution, or plastisol is compounded with the addition of one or
27
CA 02448475 2003-11-07
more of the aforementioned botanical extracts. The botanical extract is
added to the elastomer raw material in a compounding process prior to
vulcanization, solvent (or solution) evaporation, fusing or polymerization.
The emulsion, solution or plastisol of the elastomer compounded with the
botanical extract is subsequently vulcanized, evaporated/dried, fused or
polymerized to incorporate the botanical extract into one or more layers of
the finished flexible article. This is also referred to as incorporating the
botanical extract into a matrix of the elastomer (hereinalso, "the elastomer
matrix"). The botanical extract is incorporated into the elastomer malcing
one or more layers of the flexible article. If the flexible elastomer article
is
of a single layer construction, or if the article is of multi-layer
construction,
the botanical extract preferably is disposed within the layer having a wearer
contacting surface, but may be disposed within a layer having a non-wearer
contacting surface in a multi-layer flexible article. The botanical extract
enhances the physical and therapeutic properties of flexible elastomer
article(s) made from the elastomer. For NRL, the botanical extract is
selected to replace the NRL laticifer cell contents.
[0085] The selection of the elastomer(s), the selection of the botanical
extract and concentration of the botanical extract to elastomer(s) will be
discussed next. Where the elastomer is an elastomer that is suspended into
an emulsion, specific examples of suitable elastomers include an NRL, a
synthetic polyisoprene, a chloroprene (Neoprene), a PU, an acrylonitrile, a
butadiene methylmethacrylate, an SBS, an SIS, SEBS, a silicone, and an
acrylate-based hydrogel, any other elastomer that can be suspended into an
emulsion, and mixtures thereof. Where the elastomer is an elastomer that
is suspendable, soluble or miscible in a solvent (hereinalso, "solution") or a
plastisol, specific examples of suitable elastomers include a silicone, a PU,
an SIS, an SBS, an SEBS, a PVC, an acrylate-based hydrogel, any other
28
CA 02448475 2003-11-07
elastomer that is suspendable, soluble or miscible in the solution or the
plastisol, and mixtures thereof.
100861 The elastomers are so selected that the botanical extract is
miscible or soluble in the emulsion of the elastomer and any mixtures
thereof, or the botanical extract is suspendable, miscible or soluble in the
solution or plastisol of the elastomer, and any mixtures thereof. The
botanical extract selected is always suspendable, miscible or soluble in the
elastomer, e.g., emulsion, solution or plastisol compounded with the
botanical extract.
[00871 Where the elastomer is suspended into an emulsion, the botanical
extract is characterized by stabilizing the emulsion of the elastomer(s) and
maintaining dispersions of otherwise imiscible phases and inhibiting
physical processes (e.g., sedimentation, trapping of gas bubbles and the
non-uniform dispersion of rubber particles) within the emulsion of the
elastomer(s). This allows for a more uniform film deposition during the
dipping process. Further, the botanical extract is characterized by acting as
a flow modifier, providing thixotropic properties that modify the rheology
of the elastomer emulsion thereby decreasing unwanted flow of the
emulsion when forming the article. The botanical extract is also
characterized by its function as an emulsifier, actively reducing surface
tension and improving film deposition at the time of dipping. The
botanical extract is further characterized by functioning as a plasticizer
that
lowers the modulus of the finished article resulting in a softer glove with
retained strength and improved wearer comfort and as a humectant,
providing moisture homeostasis which enhances skin moisturizing
properties, lubricity and donning characteristics of the flexible article. The
botanical extract is also characterized by its antioxidant properties
preventing unwanted oxidation during manufacturing and improving shelf
29
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life of the finished article by protecting the vulnerable unsaturated carbon
bonds of the elastomer.
[0088] Preferred botanical extracts are Aloe vera extract and/or Nopal
extract. These extracts are derived from the Aloe vera plant and the Nopal
plant respectively. Both Aloe vera and Nopal are xerophytic plants which
absorb and fix carbon dioxide at night requiring the use of a crassulacean
acid metabolism (CAM). Unlike most plants which absorb carbon dioxide
during the day in the chloroplast to make sugars through photosynthesis,
the water conservation and homeostasis of Aloe vera and Nopal enables
them to absorb and fix carbon dioxide in its cytosol at night and convert the
carbon dioxide to malate. The malate is stored along with water and
polysaccharides in special centralized vacuoles which make up 95% of the
plant. During daylight the malate migrates from the vacuole back to the
cytosol where it is decarboxylated into carbon dioxide and pyruvate. The
carbon dioxide diffuses back into chloroplasts and together with light
photons make sugars through photosynthesis (see, Wang et al., "Phloem
Exudate Collected via Scale Insect Stylets for the CAM Species Opuntia
ficus-indica under Current and doubled CO2 Concentrations", Annals of
Botany 75: 525-532, (1995), Table 3, p. 529). The majority of the sugars
are polymerized into water soluble polysaccharides which are stored in the
plant's vacuoles, cytosol and apoplast. Some of these polysaccharides are
used for the conversion of carbon dioxide into malate. A proportion of
these polysaccharides are synthesized into very large molecular weight
molecules (up to 30 million daltons) in specialized mucilage cells. The
large molecular weight polysaccharides have very unique water binding
capacity and have a very important role in water conservation and storage
for these plants. Unlike starch or cellulose which are found in plants, these
polysaccharides are water soluble sugar biopolymers and are referred to as
mucinous polysaccharides.
CA 02448475 2003-11-07
[0089] As discussed previously, the botanical extract selected for
compounding with the selected elastomer has mucinous polysaccharides
(hereinalso "polysaccharide" or "polysaccharides" or "polysaccharide(s) or
"polysaccharide chain(s)" or "polysaccharide biopolymer") therein.
Mucinous polysaccharides are large molecular weight polysaccharides
without a protein attached thereto. For example, Nopal extract contains a
high molecular weight fraction that include a molecular structure of up to
30,000 sugars and a molecular weight range of 2.3 X 104 to 1.5 X 10g
daltons. The Nopal polysaccharide preferably contains varying proportions
of L-arabinose (pyranose and furanose forms), D-galactose, L-rhamnose
and D-xylose as the major neutral sugar units and also galactouronic acid.
The primary structure is a molecule with a linear repeating core chain of
(1--*4) linked beta-D-galacturonic acid and alpha(1--),2) linked L-rhamnose
with trisaccharide side chains of Beta(1-+6) linked D-galactose attached at
0(4) of L-rhamnose residues. The galactose side residues present further
branching in either 0(3) or both 0(3) and 0(4) positions. For a Nopal
extract, the composition of these polysaccharide chains is complex with at
least 20 different types of oligosaccharides which have been identified.
[0090] Mucinous polysaccharides have polysaccharide chains. The
chains of the mucinous polysaccharides of the botanical extracts are coiled
and intertwined while yet a liquid. The tensile properties created by the
unwinding and untangling of the intertwined polysaccharide slows the flow
or migration of the elastomer emulsion giving additional time for
coagulation, polymerization or drying further minimizing the thickness
disuniformity of the elastomer film (see Paulsen et al. "Water soluble
polysaccharides of opuntia ficus - indica CV "Burbanks Spineless",
Phytochemistry 18 (1979) 569-571, Wang et al., "Phloem Exudate
Collected via Scale Insect Stylets for the CAM Species Opuntia ficus-
indica under Current and doubled CO2 Concentrations", Annals of Botany
31
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75: 525-532, (1995); McGarvie et al. "The acid-labile, peripheral chains of
the mucilage of the Opuntia ficus-indica", Carbohydrate Research, 94
(1981) 57-65; Mindt et al., "Cactaceae mucilage composition", Journal of
Science and Food Agriculture, 1975, 26, 993-1000; Amin et al., "The
mucilage of opuntia ficus-indica mill.", Carbohydrate research 15 (1970)
159-161; Parikh et al. "Cholla Gum I. Structure of the degraded cholla
gum", Canadian Journal of Chemistry, Volume 44 (1966) 327-333; Parikh
et al. "Cholla Gum U. Structure of the undegraded cholla gum", Canadian
Journal of Chemistry, Volume 44 (1966) 1531-1539; Medina-Torres et al.
"Rhelogical properties of the mucilage gum (Opuntia ficus indica)" Food
Hydrocolloids 14 (2000) 417-424; Cardenas et al. "Rheology and
Aggregation of Cactus (Opuntia ficus - indica) Mucilage in Solution",
Journal of the Professional Association of Cactus Development, 2, 152-159
(1998); Saenz, "Processing technologies: an alternative for cactus pear
(Opuntia spp.) fruits and cladodes", Journal of Arid Environments (2000)
46: 209-225; which disclosures are hereby incorporated herein by
reference). These thixotropic properties are uniquely provided by a
botanical extract of Aloe vera and/or Nopal, andlor okra, and/or kelp,
and/or tamarind, and/or psyllium, and/or carrageenan, and/or chia, and/or
flax, and/or carob, and/or guar, and/or xanthan, and/or konjac, and/or
cassia, and/or tara, and/or karaya, and/or ghatti, and/or tragacanth, and/or
glucomannan, and/or galactomannan.
[0091] Alternatively, the botanical extract is a laboratory produced
polysaccharide(s) having the aforementioned properties, and may be used
alone or in combination with one or more of the aforementioned plant
derived botanical extracts. The laboratory produced botanical extracts of
polysaccharides are manufactured by known in the art techniques, such as,
but not limited to, refining, extraction, plant gene insertion into bacteria
or
other biotechnology processes, etc.
32
CA 02448475 2003-11-07
[0092] As previously mentioned, preferably the botanical extract for
incorporation within a layer of elastomer of the article is Nopal extract
and/or Aloe vera extract. In addition to the polysaccharides, Nopal extracts
and certain other botanical extracts are known to contain waxes, amino
acids and proteins. Furthermore, Nopal extracts are known to contain
alkaloids, phenols, saponins, flavonoids, ascorbic acid, carotene, alpha
amyrin, citric acid, maleic acidmethyl ester, glycoproteins, acetylsalicylic
acid, sucrose and Beta sitosterol. The Beta sitosterol has demonstrated
antihistiminic and anti-inflammatory properties, which assist in wound
healing. The acetylsalicylic acid has known analgesic properties and the
ascorbic acid has known anti-aging properties.
[0093] The botanical sources of Aloe vera are typically from, but are not
limited to, the Aloe vera and Aloe barbadensis and other species of the
Aloe plant. Hereinthroughout, the term "Aloe vera" includes the named
species Aloe vera and Aloe barbadensis and other species of the Aloe plant,
as is known in the art. The source of the Nopal (a.k.a. Cholla and Prickly
Pear Cacti) extracts are obtained from any species of the Opuntia, Nopalea
and Consolea genera (subfamily Opuntioideae), for example, but not
limited to, Opuntia ficus indica, Opuntia dillenii, Opuntia streptacantha,
Opuntia engelmanii, Opuntia fulgida, Opuntia fulginosa, Nopalea auberi,
Nopalea karwinskiana, Consolea rubescens and Consolea monoliformis.
The Nopal extract and the Aloe vera extract are commercially available
from suppliers in liquids, gels, and powders. Preferably, the Nopal extract
is made from the cladodes (pads) of the Opuntioideae plant(s).
[0094] The use of Nopal advantageously provides a substantial cost
saving in the international glove industry. Extensive commercial
cultivation of Nopal for food applications combined with a significantly
greater yield per acre per year over Aloe vera combine to make it possible
for commercial suppliers to offer water soluble Nopal extracts for less than
33
CA 02448475 2003-11-07
half the cost of the commercial Aloe vera extracts. The use of Nopal in the
present invention creates a competitive advantage in the international glove
industry (and other flexible elastomer article industries) because of this
substantial savings over Aloe vera. Other of the botanical extracts are
commercially available as will be discussed later. As is known in the art,
the polysaccharide compositions of the plant based botanical extracts (also
the plant based non-Aloe vera botanical extracts) may vary due to growing
condition, e.g., ambient C02, moisture, temperature, etc., and processing
and storage conditions.
[0095] To prepare the elastomer compounded with the botanical extract
for an elastomer where the raw material(s) is an elastomer emulsion, the
botanical extract is added to the elastomer emulsion, in a quantity sufficient
to serve as a stabilizer, a flow modifier, an emulsifier, a plasticizer, a
humectant and an anti-oxidant. An example of an elastomer emulsion is
NRL.
[0096] Where NRL is the elastomer selected for compounding, addition
of the botanical extract(s) pre-vulcanization allows the botanical extract to
be incorporated into the NRL matrix of the finished article during
vulcanization, thereby protecting the unsaturated carbon bonds of the NRL.
The addition of the water soluble botanical extracts of the preferred
botanical extracts of Nopal and/or Aloe vera (and/or kelp, and/or okra,
and/or tamarind, andlor psyllium, and/or carrageenan, and/or chia, and/or
flax, andlor carob, andlor guar, and/or xanthan, and/or konjac, and/or
cassia, and/or tara, and or karaya, and/or ghatti, and/or tragacanth andlor
glucomannan and/or galactomannan) simultaneously replaces the waxes,
lipids, amino acid and protein contents which function as a stabilizer, a
flow modifier, an emulsifier, a plasticizer, a humectant and an anti-oxidant.
[0097] Furthermore, the aforementioned selected botanical extract(s)
replace the broad spectrum of laticifer cell botanical contents in the NRL
34
CA 02448475 2003-11-07
emulsion which were removed because of the NRL protein allergy
epidemic (NRL antigen content). Replacing the laticifer cell contents in
NRL with a botanical extract without cross-reactive antigenic proteins has
a number of additional benefits. One benefit is the return of the benefits of
colloidal stabilization of the NRL emulsion, thereby improving the dipping
of a uniform NRL film thickness. Another benefit is the return of the
antioxidant properties provided by a diverse range of amino acids and
proteins, thereby protecting the vulnerable unsaturated carbon bonds of the
NRL polyisoprene. Yet another benefit is the return of a lower modulus of
the glove thereby providing a softer more comfortable glove with retained
strength, resulting from the plasticizing of the NRL by the diverse plant
molecules in the selected botanical extract including the waxes, lipids and
polysaccharides. For non-NRL emulsions, the benefits provided by the
botanical extract include the aforementioned functions of a flow modifier,
an emulsifier, a plasticizer, a humectant, an antioxidant and/or therapeutic
properties.
[0098] Alternatively, to prepare the elastomers compounded with the
botanical extract for the elastomer where the elastomer raw material is
made from a solution or plastisol, the botanical extract is required to be
suspendable, soluble or miscible in the solution or plastisol and is added to
the solution or plastisol. In this instance, specific examples of suitable
elastomers include a silicone, a PU, a PVC, an SIS, an SEBS, an SBS, an
acrylate-based hydrogel, any other elastomer wherein the botanical extract
is suspendable, soluble or miscible in the solution or plastisol, and mixtures
thereof. The introduction of the aforementioned selected botanical
extract(s) to make the elastomer compounded with the botanical extract for
a non-NRL elastomer provides the benefits of antioxidant and therapeutic
properties as described above.
CA 02448475 2003-11-07
[0099] In the compounding process, the botanical extract is added to the
elastomer raw materials in concentrations which preferably result in a
glove or other flexible article which complies with and does not fall outside
of the physical attributes called out in applicable ASTM and ISO
specifications, for gloves (see standards supra) for the particular elastomer
material and the target physical properties for the flexible articles (other
ASTM, ISO, industry and/or regulatory standards, as is known in the art).
[00100] Thus, in making the flexible elastomer article of the present
invention, the use of the aforementioned botanical extracts advantageously
provides an optimal polysaccharide biopolymer addition to the elastomer,
by stabilizing and maintaining dispersions within the emulsion of the
elastomer, modifying flow through thixotropic properties that prevent
unwanted flow of the emulsion, acting to emulsify or reducing surface
tension allowing for a more uniform deposition of the elastomer film, by
serving as an antioxidant that increases shelf-life of the finished article,
by
acting as a plasticizer and lowering the modulus of the finished article and
improving wearer comfort, and by providing moisture homeostasis
properties that enhance moisturizing properties, lubricity and donning
characteristics of the flexible article thereby, producing a glove (or other
flexible elastomer article) with a more uniform thickness and enhanced
durability, functionality and comfort. In addition, the botanical extract
advantageously contains therapeutic components having one or more of the
qualities of wound healing, anti-inflammatory properties, anti-microbial
properties, analgesic properties, and anti-aging properties. In the preferred
embodiment, the botanical extract selected is an Aloe vera extract.
Alternatively, the botanical extract selected is also preferably a Nopal
extract. Alternatively, the botanical extract is preferably a mixture of an
Aloe vera extract and a Nopal extract. Alternatively, the botanical extract
is selected from the group of extracts of Aloe vera, Nopal, okra, kelp,
36
CA 02448475 2003-11-07
tamarind, psyllium, carrageenan, chia, flax, carob, guar, xanthan, konjac,
cassia, tara, karaya, ghatti, tragacanth, glucomannan, galactomannan, a
laboratory produced polysaccharide, and mixtures thereof. The botanical
extract is preferably water soluble.
[01011 As previously discussed, the elastomer compounded with the
botanical extract may be formulated in a number of ways, e.g., via
emulsion, solution or plastisol. In the preparation of the present invention
for incorporating the botanical extract into the elastomer, the units of phr
are used. Phr measures the concentration of the botanical extract in a
finished article. (Also, see Table A1.2 of ASTM D 573-99 illustrating use
of standard formulations of rubber compounds based on phr.) Phr is parts
per hundred weight of rubber or in this invention, phr also means parts per
hundred weight of elastomer. Phr is a measure of dry weight, used to
reflect the botanical extract concentration in the finished article, e.g.,
weight of material, in this instance, botanical extract, per one hundred
weight of elastomer. A concentration of botanical extract to elastomer
ranges from about 0.2 to 5.0 phr but, preferably ranges from about 0.2 to
2.5 phr. Concentrated solutions of one or more of the water soluble
botanical extracts of the present invention, are made and added to the
elastomer emulsion, plastisol or solution during the well known
compounding steps of flexible article (for example, glove) production. The
elastomer that is prepared according to the compounding step is referred to
as an elastomer compounded with the botanical extract.
[0102] The use of the phr unit rather than percent of botanical extract by
volume is preferred because of the significant variability in the
concentration of elastomer-to-water/solvent/plastisol in the raw materials
from which the elastomer is produced. For example, for NRL, the rubber-
to-water concentration per volume may vary by batch of raw material and
by weather conditions, e.g. rain, drought, etc. Some shipments of liquid
37
CA 02448475 2003-11-07
NRL (pre-compounding) may have high rubber to water ratios and others
have low rubber-to-water content. For example, some elastomers may be
shipped in concentrated solutions, e.g. 70% wt/volume to avoid shipping
excess water that may be added back during the elastomer compounding
phase of production. The addition of the botanical extract is tied to the
total rubber (or other elastomer) concentration in the liquid emulsion, and
not the volume of the water. In this way, one can assure a constant
quantity of botanical extract in the finished flexible elastomer article. By
using the phr designation of concentration, it makes it also possible to have
variability in the process of adding the botanical extract to the elastomer
emulsion, solution, or plastisol.
[0103] For example, for NRL, a density measurement may be made of an
elastomer raw material to determine the density "d" (or specific gravity) of
the elastomer in terms of gm/ml of elastomer (or other units of density).
Knowing the volume "V" of the raw material one can easily calculate the
weight WE of elastomer.
V=d=WE
[0104] Knowing the weight WE of the elastomer in the volume of
elastomer, one can calculate the amount (weight) of the botanical extract
(WBE) needed for a specified phr.
[0105] Once the WBE (amount of botanical extract) is determined, a
weight/volume percentage solution of botanical extract can be formulated,
depending on the elastomer, the flexible article to be made and the process
used. WBE is added to the elastomer raw material in a quantity sufficient to
produce the specified phr in the finished flexible elastomer article. Where
multi-layer flexible articles are made, the WE is based on the total weight
of elastomers used in the different layers of the finished article and the
above formulas can be easily modified. For other non-NRL (non-botanical
source) elastomers where the weight of the elastomer is known, the weight
38
CA 02448475 2003-11-07
of the botanical extract can be calculated by ratio to achieve the specified
phr.
[0106] The botanical extract is typically prepared in water solution to be
added to the elastomer. For example, a ten percent (10%) water solution of
the botanical extract may be mixed as a practical concentration for
rehydration of a powdered botanical extract. Each time a batch of
elastomer is compounded, there could be variability in the rubber content
(or other elastomer content or elastomer mixture content) of the inbound
liquid raw materials which would make the volume of a ten percent (10%)
concentration added to achieve a lphr change. It could also happen that a
more concentrated solution of the botanical extract would be prepared in
order to achieve the target phr without a viscosity change of the emulsion,
solution or plastisol exceeding or not being in conformance with the
proprietary manufacturing parameters for making flexible elastomer articles
of the type being produced.
[0107] Typically, in the present invention, the preferred range of the phr
is about 0.2 to 2.5 for weight of botanical extract per hundred weight of
elastomer. It is possible for the range to extend from about 0.2 to 5.0 phr,
depending upon the article to be made and the proprietary process nuances.
A higher phr may be necessary in certain processes where a post cure leach
is performed to reduce the antigenic protein which concomitantly reduces
too much of the botanical extract. Preferably, the range of phr of botanical
extract to elastomer in the finished flexible article may differ from the
stated ranges, but in any case, is in a quantity sufficient that the physical
performance standards of the article, e.g., those designated in the ASTM
and ISO standards (above) or equivalent standards or other allowable pre-
market certification requirements, such as, but not limited to, FDA
requirements, for gloves or other flexible articles are met. For example, an
instance of exceeding the ASTM, ISO or other standards occurs where a
39
CA 02448475 2003-11-07
phr is used which may produce a softer feeling product, but where the
product fails a tensile strength standard of the ASTM, ISO, or other
standard.
[0108] The performance standards, for example, for gloves, are physical
requirements (also called "tensile properties" in the ISO Standards) and
performance requirements, such as, freedom from holes, physical
dimensions and tolerances, physical properties, powder-free residue,
protein content, powder amount, etc. The performance requirements and
physical requirements from the aforementioned ASTM and ISO
specifications supra are herein incorporated by reference. Test methods for
the physical requirement tests and performance requirements are conducted
according to the appropriate ASTM, ISO, or other, known in the art, testing
standards (see ASTM Standards supra) or other regulatory standards or
other pre-market certification requirements. The physical requirements
pertain to parameters before aging, such as, tensile strength and an ultimate
elongation, stress at 500% elongation, and parameters after accelerated
aging, such as, tensile strength and ultimate elongation. The botanical
extract selected and used in the present invention is in a quantity sufficient
in the finished article for the finished article to maintain, and to not fall
outside the physical requirements of the ASTM, ISO and/or other known
standards for the particular flexible article made. For gloves, ASTM and
ISO physical requirements include, but are not limited to, physical
requirements in physical requirement tables of the following publications:
ASTM D 3577-01aE2 - Table 3, ASTM D 5250-00e4 - Table 3, ASTM D
6319-00aE3 - Table 3, ISO 11193-1:2002(E) - Table 3, ISO 10282: 2002(E)
- Table 3, ASTM D 3578-01aE2 - Table 1, and ASTM D 4679-02 - Table 3,
ail the disclosures of which are hereby herein incorporated by refcrcnce.
Thus, a concentration of botanical extract in the flexible article of the
present invention is an amount sufficient to optimize benefits without
CA 02448475 2003-11-07
compromising the physical requirements and performance requirements-
required by the applicable ASTM and/or ISO specifications, and/or other
known standards and/or other known pre-market certification requirements
for tensile strength, modulus, ultimate elongation, and aging, and/or for
freedom from holes, physical dimensions, physical properties, powder-free
residue, protein content and powder amount.
[0109] Where the article is a glove, the types of gloves include
disposable gloves or reusable gloves, the glove may be an examination
glove, a surgical glove, an industrial glove, a protective glove or a
household glove. Flexible articles of the present invention include articles
having a single or multiple layers of elastomer. Where the glove is the
article, a single layer glove or a bilaminar glove (two layers) or a multi-
layer glove is comprehended by the present invention. Where the glove is
a single layer glove (or other single layer article), specific examples of the
suitable elastomers include a NRL, a synthetic polyisoprene, a chioroprene,
PU, an acrylonitrile, a butadiene methylmethacrylate, an SBS, an SIS, an
SEBS, a silicone, an acrylate-based hydrogel, any other elastomer that
could be suspended into an emulsion, and mixtures thereof. Thus, the
single layer article (or glove) could be made of one or more of the
aforementioned elastomers. The botanical extract for the single layer glove
may be any one of or any mixture of the aforementioned botanical extracts.
Preferably the botanical extract is an Aloe vera extract or a Nopal extract or
both. A single layer of an elastomer may be achieved by multiple dipping
of an article former into the same elastomer. In other words, a single
elastomer (or mixture of elastomers) which is multi-dipped is considered
herein to form a single layer elastomer article or one layer of a multi-layer
elastomer article.
[0110] Where the glove is the bilaminar glove (or other two layer article)
having a first layer having the distal (or outer surface) and a second layer
41
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having the wearer contacting surface, the first layer and the second layer
may be made of a similar or a dissimilar elastomer(s) and the botanical
extract is incorporated into at least one layer of the glove. For the layer of
the glove into which the botanical extract is incorporated, the elastomer is
any elastomer or combination of elastomers that can be suspended into an
emulsion or any elastomer or combination of elastomers that is
suspendable, soluble or miscible in a solution or a plastisol and wherein the
botanical extract is soluble or miscible in the same emulsion, solution, or
plastisol.
[0111] Specific examples of suitable elastomer(s) used for either the first
layer or the second layer of a bilaminar glove include an NRL, a synthetic
polyisoprene, a chloroprene, a PU, an acrylonitrile, a butadiene
methylmethacrylate, an SBS, an SIS, an SEBS, a silicone, an acrylate-based
hydrogel, a PVC, any other elastomer or combination of elastomers that
could be suspended into an emulsion, or any elastomer or combination of
elastomers that is suspendable, soluble or miscible in a solution or a
plastisol, and mixtures thereof. Thus, each layer of the two layer article
could be made of a single elastomer or a mixture of the aforementioned
elastomers. The botanical extract is soluble or miscible in the emulsion,
solution, or plastisol of the elastomer for the layer of the glove into which
the botanical extract is incorporated and the botanical extract is preferably
any one of or a mixture of any of the aforementioned botanical extracts.
The botanical extract is most preferably an Aloe vera extract or a Nopal
extract or a combination of both Nopal extract and Aloe vera extract. In
the most preferred embodiment, the bilaminar glove has a first layer of
PVC and the elastomer selected for the second layer is PU and/or silicone.
In the preferred embodiment the botanical extract is incorporated into the
second layer of the glove.
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[0112] Where the glove is a multi-layer glove (or other multi-layer
article) the glove has a first layer having an outer surface, a layer having
the wearer contacting surface and one or more layers disposed between the
first layer and the layer having the wearer contacting surface. The
botanical extract is in at least. one layer of the glove (or article).
Specific
examples of suitable elastomers selected for each layer of the glove include
an NRL, a synthetic polyisoprene, a chloroprene, a PU, an acrylonitrile, a
butadiene methylmethacrylate, an SBS, an SIS, an SEBS, a silicone, an
acrylate-based hydrogel, a PVC, any other elastomer or combination of
elastomers that could be suspended into an emulsion, any other elastomer
or combination of elastomers that is suspendable, soluble or miscible in a
solution or plastisol, and mixtures thereof. Thus, each layer of the multi-
layered article could be made of a single elastomer or of a mixture
(combination) of the aforementioned elastomers. The botanical extract is
soluble or miscible in the emulsion, solution, or plastisol of the elastomer
for the layer of the glove into which the botanical extract is incorporated
and the botanical extract is preferably any one of or a mixture of any of the
aforementioned botanical extracts. In the preferred embodiment, the
botanical extract is an Aloe vera extract or a Nopal extract or both.
[0113] In the flexible article of the present invention and for the gloves of
the present invention, the preferred botanical extract is derived from plant
material and is one or more extracts of Aloe vera, Nopal, okra, kelp,
tamarind, psyllium, carrageenan, chia, flax, carob, guar, xanthan, konjac,
cassia, tara, karaya, ghatti, glucomannan, galactomannan, or tragacanth.
Yet alternatively, the botanical extract is a laboratory produced
polysaccharide. Yet alternatively, the botanical extract is one or more of
the aforementioned extracts derived from plant material and the laboratory
produced polysaccharide.
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[0114] In the second aspect of the present invention, a wearer contacting
surface of the flexible elastomer article is coated to improve moisturizing
characteristics and donnability with a non-Aloe vera coating material which
is fortified by additives known to protect and restore mammalian sldn.
Hand sweating beneath a glove (or other flexible elastomer article) with
chronic use is known to be a contributor to irritant contact dermatitis, see
supra. The ability to reversibly absorb the perspiration without the
abrasive properties of cornstarch is an advantage over the prior art. The
improvement of moisturizing characteristics is a function of the water
homeostasis after the flexible article is donned.
[0115] With regard to the second aspect, the non-Aloe vera coating
material is placed upon a surface of the flexible elastomer article,
preferably a wearer contacting surface, such as the inside of an article,
most preferably the inside of a glove. The non-Aloe vera coating material
is a non-Aloe vera mucinous botanical polysaccharide and/or a non-Aloe
vera laboratory produced polysaccharide, (both polysaccharides
collectively herein also referred to as "a non-Aloe vera botanical extract")
having the aforementioned properties of the botanical extracts and
preferable polysaccharides, and having a water weight gain of at least
110% determined by an adsorption isotherm performed at 35 C, thus,
excluding Aloe vera extract. The non-Aloe vera laboratory produced
polysaccharide is manufactured by known in the art techniques, such as,
but not limited to, refining, extraction, plant gene insertion into bacteria
or
other biotechnology processes, etc. The non-Aloe vera coating material for
coating the wearer contacting surface of the article is preferably a non-Aloe
vera botanical extract that serves as a moisture regulator, a moisturizer, a
lubricant/donning agent, a flow modifier aiid imparts a range of
therapeutically relevant physiologic benefits including anti-microbial,
44
CA 02448475 2003-11-07
wound healing, anti-inflammatory, analgesic and anti-aging (oxidation
injury) properties.
[0116] In the preferred embodiment, the non-Aloe vera coating material
is a non-Aloe vera botanical extract which is preferably fortified with one
or more additives. In the preferred embodiment, the non-Aloe vera
botanical extract used for the non-Aloe vera coating material on the inside
of the glove or on a surface of the flexible article is Nopal extract. In the
most preferred embodiment Nopal is used to make a solution of the non-
Aloe vera coating material. The non-Aloe vera botanical extracts, e.g.,
polysaccharide sources include, but are not limited to Nopal extract, and/or
okra extract, and/or kelp extract, and/or tamarind extract, and/or psyllium
extract, and/or carrageenan extract, and/or chia extract, and/or flax extract,
and/or carob extract, and/or guar extract, and/or xanthan extract, and/or
konjac extract, and/or cassia extract, and/or tara extract, and/or karaya
extract, and/or ghatti extract, and/or tragacanth extract, and/or
glucomannan, and/or galactomannan, and/or laboratory produced non-Aloe
vera polysaccharides. Specific examples of suitable additives to the
botanical extract include one or more of Vitamin A, Vitamin E, Vitamin C,
Vitamin B3, Vitamin B5, jojoba, rose hips, tea tree oil, flax seed oil, palm
oil, and acetylsalicylic acid. (It is to be noted that flax extract is made
from
the hull of the flax seed and is not identical to flax seed oil which is made
from the inside of the flax seed.)
[0117] For the non-Aloe vera surface coating material, the concentration
range of the non-Aloe vera botanical extract may be a 5% to 20% solution
(water and/or ethanol), but may be prepared in a 1% to 50% solution; more
preferably an 8% to 12% solution is used; most preferably a 10% solution
is used.
[0118) The non-Aloe vera coating material may also be expressed in
units of phr of the non-Aloe vera botanical extract per hundred weight of
CA 02448475 2003-11-07
elastomer in the finished product. The phr for the coating material may
possibly be determined by industry standards or guidelines for a particular
non-Aloe vera coating material in the finished flexible elastomer article.
To calculate the phr for a surface coating, the density of the elastomer(s)
and the elastomer concentration is calculated. Knowing the elastomer
concentrations allows the calculation of appropriate quantity of non-Aloe
vera botanical extract to be added to yield the prescribed phr.
(Alternatively, if the weight of elastomer is known, and a phr selected, the
weight of the non-Aloe vera botanical extract is calculated by ratio.)
[0119] The amount by weight of non-Aloe vera botanical extract is then
suitably mixed into a water and/or ethanol solution and applied as a surface
coating to a surface of the flexible article by spraying, tumbling, soaking,
dipping and in other ways known in the art for applying a surface coating.
The percentage concentration (or phr) of the non-Aloe vera botanical
solution depends upon the type of application to the article and/or the
drying conditions. The additive(s) may be added in usual amounts to meet
content labeling requirements known in the industry.
[0120] The thixotropic properties of the polysaccharide biopolymer
component of the most preferred Nopal extract (or the other
aforementioned non-Aloe vera botanical extracts) makes it function as a
liquid biopolymer making it possible to uniformly apply a coating with a
dip, spray, tumble and spray, or soaking method and air or oven dry a
uniform coating thickness on the surface of a chlorinated or non
chlorinated glove, or other flexible article. Nopal has desirable sheer
thinning properties providing "peeling" behavior in an increasing Nopal
solution concentration (see Cardenas et al. supra). A quantity of Nopal
extract (or other non-Aloe vera botanical extract) sufficient to reduce th%-,
rubber or plastic blocking and provide adequate lubriciousness when dry
donning (not greater than 2500g frictional donning forces using a load
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tester; Cote et al., 1998 Journal of Biomedical Materials Research, 43:331-
337) is used in the present invention.
[0121] There is a distinction in wearer comfort between donnability due
to the coating material and wearer comfort due to the moisturizing
properties of the coating material, e.g., improvement of the perception of
comfort caused by the water homeostasis after the flexible article is
donned. The present invention advantageously improves the wearer
comfort due to the moisturizing properties. This is best understood by the
water sorption isotherms of the present invention. A sorption isotherm of
an article (or material) shows the relationship between water activity and
moisture content of the article (or material or compound) at equilibrium (or
steady state) at constant temperature. The water activity can be expressed
as relative humidity (RH) of the surrounding air. Typically the RH ranges
from 5% to 95% (or higher, but less than 100% RH). The moisture content
at equilibrium can be expressed as percentage weight gain (or loss) of the
article(or material) due to picking up moisture or losing moisture to the
surrounding air. The sorption isotherm can be expressed as a desorption
isotherm or as an adsorption isotherm.
[0122] Desorption isotherms show the loss of moisture from the material
equilibrating with the surrounding air. Desorption isotherms typically start
at 95% RH (or higher, but less than 100% RH) and decrease to 5% RH.
Adsorption isotherms illustrate the gain of moisture to the material
equilibrating with the surrounding air. Adsorption isotherms typically start
at 5% RH and increase to 95% RH (or higher, but less than 100% RH).
The difference between the desorption isotherm and the adsorption
isotherm is hysteresis. Hysteresis illustrates the phenomena where water is
more easily absorbed at a given relative humidity and temperature than
released; this is shown by the desorption isotherm being above the
adsorption isotherm. This would mean a higher steady state weight for a
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particular sample at a particular relative humidity if the study began at 95%
RH (or higher, but less than 100% RH) versus 5% RH. This is illustrated
by silica crystals used as a desiccant to reduce humidity in packaging of
small electronics where moisture is easily absorbed and tenaciously
retained. The weight gain or weight loss is calculated at a given relative
humidity at such time as a steady state (equilibrium )is reached. This
means that no additional weight gain or loss occurs at the given relative
humidity and temperature.
[0123] The adsorption-desorption isotherms of the cladode (whole leaf
pad) of Opuntia ficus indica have been studied experimentally and
compared with predictive mathematical models to study the influence of
temperature on equilibrium moisture content. In the reported study, the
cladode is dehydrated in a 50 C drying oven for the adsorption isotherm
and a fresh cladode is used for the desorption isotherm. The whole leaf
pad is able to absorb up to 100% of its dry weight. (See, Lahsasni, et al.,
"Moisture adsorption-desorption isotherms of prickly pear cladode
(Opuntia ficus) at different temperatures", Energy Conversion and
Management 44 (2003) 923-936, the disclosure of which is herein
incorporated by reference.)
[0124] As best shown in FIG. 25, a comparison of the measured
adsorption isotherms, an advantageous unexpected result was discovered
when full isotherms were performed on Nopal extract of the present
invention and compared with the Aloe vera extract used for coating in the
prior art and other known in the art coating materials. It was discovered
that Nopal absorbs twice the moisture of Aloe vera at maximum relative
huniidity thereby illustrating the dramatic improvement of the present
invention over the prior art coating materials.
[0125] For FIGs. 25-31, water sorption studies were conducted using a
water vapor sorption analyzer, HYDROSORB 1000 made by
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Quantachrome Instruments, Boynton Beach, FL, USA, using standard
techniques for measuring adsorption and desorption isotherms. The
isotherm data was collected at 35 C, which approximates human hand
(body) temperature under a glove. Sorption isotherms were obtained for
samples of Nopal (FIG. 26), Aloe vera (FIG. 27 adsorption only),
cornstarch (FIG. 28), silicone powder (FIG. 29) and a polyurethane (FIG.
30) and for vinyl gloves treated with an interior surface coating of Nopal
extract and Vitamin E and with Aloe vera extract and Vitamin E (FIG. 31).
FIG. 25 is an overlay of the adsorption curves shown in FIGs. 26-30. The
absorbate was water with a molecular weight of 18.01, an absorbate cross-
section area of 12.5, and absorbate density of 0.997, a gas factor of 3.OOE-
05. The adsorption isotherms were plotted as % weight gain versus RH%.
The Nopal absorbs approximately twice the moisture as the Aloe vera as
shown in FIGs. 25 and 31 at maximal absorption, approximately 98%-
99%RH.
[0126] Comparing the isotherms of the various coating used on gloves
helps elucidate the distinct properties which the Nopal and Aloe vera
contribute to the surface of a glove. Cornstarch, silicone and polyurethane
are common glove interior surface coatings used as donning lubricants
(supra). The cornstarch isotherm shown in FIG. 28 is significant because it
maximally absorbs only 23% by weight of hand moisture (also adsorption
isotherm shown in FIG. 25). A significantly larger quantity of cornstarch
would need to be applied to a glove to absorb the same amount of sweat as
using Nopal. The desorption isotherm shown in FIG. 28 also demonstrates
hysteresis. Water is more easily absorbed than released very likely
contributing to the negative perception of powder drying the hands out too
much for some users. Should hands desiccate with a glove treated with
Nopal or Aloe vera, the polysaccharides would easily release their water
back to the epidermis of the skin, much as the polysaccharides function as a
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water reservoir within the plant. The cornstarch isotherm illustrates
another problem that a significant proportion of water absorption occurs
within the range of relative humidities encountered in normal storage. This
increases the water content of a stored glove which is known to increase
the problems with increasing bioburden over time and also causes a
problem with the gloves "bricking" (the gloves stick together). The
bioburden occurs in non-sterile gloves where during the manufacturing and
packing process, the gloves may become contaminated with bacteria, fungi
and viruses on the wear-contacting surface and on the outside surface. The
cornstarch plus water provides nutrients for microbes, e.g., bacteria, fungi
and viruses to multiply. The bioburden becomes a significant issue if the
patient in contact with the glove is immuno-suppressed, where the
microbes may produce serious health problems.
[0127] As shown in FIGs. 29 and 25, silicone maximally absorbed 16%
by weight of water. Because silicone lubricant is very thin, it represents
significantly less than 1% (one percent) by weight of the glove; the silicone
is ineffective with water homeostasis beneath the glove. Thus, although
silicone is used for donnability, it does not influence the perception of
comfort caused by the water homeostasis after the glove is donned.
[0128] As shown in FIGs. 30 and 25, the commercially available
polyurethane coating maximally absorbed about 45% by weight which is
half of the maximum absorption of the Aloe vera extract and a quarter of
the Nopal extract. Similar to silicone, polyurethane is used to improve
donnability, but fails to improve the perception of comfort caused by the
water homeostasis after the glove is donned.
[0129] To further explore and validate the measurable impact of water
adsorption capacity, narrower sorption isotherms for gloves were measured
at body temperature (35 C) (approximating the hand moisture environment
under a glove next to the wearer's skin) and at a RH range of 80% to
CA 02448475 2003-11-07
approximately 99% RH. Sorption isotherms were measured for a vinyl
(PVC) glove treated with an interior coating of the Nopal extract of the
present invention and Vitamin E and for a commercially made vinyl glove
(PVC) treated with an interior coating of a Aloe vera extract and Vitamin
E. The sorption isotherms were measured on samples of glove fmgers cut
from gloves treated with the respective coating material. The isotherms
were plotted as Weight Gain % versus Relative Humidity (RH%), as shown
in FIG. 31. The glove treated with the Nopal and Vitamin E gained about
twice the water weight maximally absorbed as the glove treated with Aloe
vera and Vitamin E. The ability of the Nopal to contribute to water
homeostasis between the hand and the glove as a glove coating contributes
to user satisfaction and comfort.
[0130] Furthermore, since the Nopal samples both in FIGs. 26 and 31
show little hysteresis in the isotherms; the ability to reversibly absorb
perspiration without the abrasive properties of cornstarch is an advantage.
If the same water homeostasis can be accomplished with half the quantity
of an extract and still satisfy the customer(wearer), an economic advantage
occurs.
[0131] From the data shown in FIGs. 26 and 31, the non-Aloe vera
botanical extract includes polysaccharide sources with a water sorption
isotherm at body temperature (about 35 C) which exhibits at least 110%
water weight gain at about 98% to 100% relative humidity. The
hydrophyllic nature of the non-Aloe vera botanical extract is clearly
demonstrated.
[0132] The uniform distribution of the polysaccharides provides for an
optimal reservoir for water homeostasis beneath the glove keeping the skin
appropriately moist during use. In addition, the uniform bioavailability of
the active intrinsic compounds of the Nopal or added compounds
(additives) is maximized.
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[0133] The Nopal extract is used as a glove coating to replace cornstarch
powder as a donning agent and/or as a releasing agent which prevents the
finished articles from sticking to themselves or to the formers on which
they are made. Advantageously, the stabilizing thixot,ropic properties of
the polysaccharide biopolymer component of the Nopal extract allows for
uniform application of a coating to the surface of the glove. The moisture
regulating adsorption and desorption isotherms of the Nopal polysaccharide
biopolymer coating advantageously optimize water homeostasis beneath
the glove. Historically, Nopal has been used in folk medicine. More
recently, experiments have been performed on various plant materials (for
example see U.S. Patent Application No. 2002/0132021 to Raskin et al.).
There is current information that the Nopal extract contains compounds
with a range of therapeutically relevant physiologic activity including
moisturizing, anti-microbial, wound healing, anti-inflammation, analgesia
and anti-aging properties (see Ahmad, Antiviral Research 30 (1996) 75-85;
Park et al., Filoterapia 72 (2001) 288-290; Loro et al., Journal of
Ethnopharmacology 67 (1999) 213-218; Park et al., Filoterapia 72 (2001)
165-176; U.S. Patent No. 6,447,820, to Niazi; Park et al., Archives of
Pharmacal Research, Vol. 21, Issue 1, Feb. 1, 1998, pp. 30-34; Budinsky et
al., Prostaglandins, Leukotrienes and Essential Fatty Acids (2001), 65(1),
45-50; U.S. Patent No. 6,099,866, to Slimak; U.S. Patent No. 5,800,818 to
Prugnaud et al.; and U.S. Patent Application Publication No.
2002/0102317, to Gutterrez et al.).
In addition the Nopal extract is an optimal vehicle to
fortify with vitamins and chemicals which enhance the protection of the
skin of the user.
101341 Most advantageously, data comparing the Aloe vera extract and
the Nopal Extract found that no free sugar (reducing sugars or
monosaccharides) exists in the Nopal extract whereas the Aloe vera extract
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contains several percent using a Benedict test. The extract samples were
quantitatively tested for reducing sugar using Benedict solution using
standard color reactions. The Aloe vera extract tested "strongly positive"
for reducing sugars. The Nopal extract tested "negative" for reducing
sugars. A more sensitive HPLC test was performed to measure free sugars
in the Nopal extract and the Aloe vera extract. The results are shown in
Table 1 below.
Table 1 HPLC of Sugars in Alcohol Soluble Fractions
SAMPLE SUGARS 75% ethyl alcohol % of original sample
soluble %
Aloe vera extract Sucrose 11.54 1.00
Glucose 27.95 2.43
Fructose 14.26 1.24
Nopal Extract Sucrose 7.94 0.24
Glucose 1.32 0.04
Mannose 1.62 0.05
Fructose 0.99 0.03
The Free sugar content for the Nopal extract is considerably smaller than
that of the Aloe vera extract as shown in Column 4 of Table 1 supra.
Existing strategies to minimize the bioburden with examination gloves
include maintaining a low moisture content during transportation and
storage and using biocides. These measures traditionally have been used to
minimize microbial (fungi, bacterial and virus) growth. Substitution of
non-Aloe vera botanical extract having non-detectable amounts of free
sugars as measured by the Benedict solution test or lessened amounts as
illustrated by the HPLC test supra for coating materials, preferably Nopal
extract, has an unexpected benefit and advantage over Aloe vera as a
coating material in providing minimization of bioburden by reducing the
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amounts of nutrients for microbial growth. Advantageously, this results in
reducing costs in production when biocides are reduced or elinninated.
Another advantageous result is an increase in shelf-life due to lessened
microbial growth. Another important advantage is fewer infections in auto-
immune suppressed persons due to the diminished exposure to bioburden in
non-sterile articles.
[0135] A sugar analysis of the hydrolized polysaccharide chains yields
the identical sugar subunits (rhamnose, arabinose, xylose, mannose,
galactose, and glucose). The identical sugar subunits, as well as, the
isotherm properties and free sugar properties of Nopal extract over Aloe
vera extract are surprising and unexpected results providing the advantages
for non-Aloe vera coating materials discussed supra.
[0136J The aforementioned botanical extracts, the aforementioned non-
Aloe vera botanical extracts, including the glucomannan, the galactomannan,
and the aforementioned additives are commercially available. For example,
for both types of aforementioned extracts or for materials for making both
types of the aforementioned extracts see Aloe Laboratories Harlingen, Texas,
U.S.A.; Voigt Global Distribution, Natunola Health, Nepean, Ontario
Canada; P.L. Thomas; Xiamen Xing Da Chemicals; Konjac Foods USA,
Cupertino, CA, U.S.A.; purified glucomannan; purified galactomannan
(Fenu-Pure from NatuR&D, the Nutraceuticals Division of Adumim Food
Ingredients, Industrial Zone, Mishor Adumim, Israel. The laboratory
produced polysaccharides and the non-Aloe-vera laboratory produced
polysaccharides, of the present invention are
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manufactured by known in the art techniques, such as, but not limited to,
refining, extraction, plant gene insertion into bacteria or other
biotechnology processes, etc.
[0137] Another aspect, a third aspect of the invention includes a
botanical extract incorporated in an elastomer layer forming the flexible
article and a non-Aloe vera coating material being coated preferably on at
least the wearer contacting surface of the flexible article. The elastomer(s)
used for the flexible article are any of the aforementioned elastomer(s); the
botanical extract for incorporation into an elastomer layer forming the
flexible article and the non-Aloe vera coating material used on the wearer
contacting surface of the flexible article are those previously discussed
supra. FIGs. 8-10 and 23 illustrate this aspect with respect to a glove.
However, as one of ordinary sldll in the art will appreciate, the present
invention comprehends making single, bilaminar, and multi-layered
flexible articles with a botanical extract incorporated into at least one
layer
and providing a surface non-Aloe vera coating material on preferably at
least the wearer contacting surface; this is shown by the combination of
FIGs. 11 and 12. The elastomers, the botanical extracts(s) and the non-
Aloe vera coating materials selected for the single, bilaminar and multi-
layer elastomer gloves disclosed supra and below may also preferably be
used to make the single layer, bilaminar and multi-layer flexible elastomer
articles of the present invention.
[0138] Referring now to the FIGs. 1-10 and 13-23 in which a glove and
glove making procedure is illustrated. FIGs. 11 and 12 illustrate a process
for making other flexible articles according to the present invention. The
elastomer(s) disclosed for the glove may be used for the other types of
flexible articles supra, as well as for the glove. The FIGs. are not drawn to
scale. The shadings for the specific elastomer(s) have been omitted for
simplicity in understanding the invention. It is to be understood that
CA 02448475 2003-11-07
elastomer material(s) are used in the flexible elastomer articles of the
present invention.
[0139] Referring first to FIG. 1, a medical or dental examination,
procedure, disposable and/or surgical glove 100 is illustrated as having an
outside surface (distal surface or outer distal surface or outermost surface)
(OS) 102 and an inside or wearer contacting surface (WCS) 104. The raw
material from which the glove is made includes an elastomer such as an
NRL, a synthetic polyisoprene, a chloroprene, a PU, an acrylonitrile, a
butadiene methylmethacrylate, an SBS, an SIS, an SEBS, a silicone, an
acrylate-based hydrogel, any other elastomer that can be suspended into an
emulsion, and any mixtures of any of the aforementioned elastomers.
Alternatively, the raw material includes an elastomer such as an SBS, an
SIS, an SEBS a silicone, a PU, a PVC, an acrylate-based hydrogel, any
other elastomer that is suspendable, soluble or miscible in a solution or
plastisol, and mixtures thereof, wherein the botanical extract is
suspendable, soluble or miscible in the solution or plastisol, and mixtures
of the aforementioned elastomers.
[0140] FIGs. 2-10 and 22 and 23 are cross sectional views of gloves
which have an exterior appearance similar to glove 100 and have an OS
102 and a WCS 104. In FIGs. 2, 3, 4, 22, 8, 9, 10, 23 the quantity of
botanical extract incorporated into a layer (or layers) of the elastomer (or
elastomers) is approximately 0.2 to 2.5 phr (0.2 to 2.5 parts of botanical
extract per 100 parts of elastomer in the dry weight of the finished article).
The quantity of botanical extract is calculated as described supra and a
solution (preferably water) of the botanical extract is compounded with the
elastomer(s) raw material in a quantity sufficient to achieve the specified
phr for the finished article.
[0141] FIGs. 2-4 and 22 illustrate a first aspect of the present invention
wherein a glove has a botanical extract incorporated into the elastomer
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matrix of the article. The preferred elastomer, botanical extract and phr
range selected for the single layer glove are also preferably used for other
single layer flexible elastomer articles of the present invention.
[0142] The elastomer selected for a single layer glove and botanical
extract for incorporation into the elastomer are as disclosed supra for a
single layer glove. Referring next to FIG. 2, a preferred embodiment single
layer glove 106 is made from preferably an elastomer emulsion, solution or
a plastisol compounded with Aloe vera extract 108 and/or Nopal extract
110. The elastomer compounded with the botanical extract 108, 110 is
then vulcanized, polymerized, cured, evaporated and/or fused so as to
incorporate the botanical extract 108, 110 into the elastomer matrix.
Preferably the elastomer(s) is prepared in the elastomer emulsion and
includes an elastomer selected from a NRL, a synthetic polyisoprene, a
chloroprene, a PU, an acrylonitrile, a butadiene methylmethacrylate, an
SBS, an SIS, an SEBS, a silicone, an acrylate-based hydrogel, any other
elastomer that can be suspended into an emulsion, or a mixture of one or
more of the aforementioned elastomers. Preferably, where a solution or a
plastisol of an elastomer is prepared, the elastomer includes an elastomer
selected from a silicone, a PU, an acrylate-based hydrogel, an SEBS, an
SIS, an SBS, a PVC, any other elastomer wherein the botanical extract is
suspendable, soluble, or miscible, or a mixture of one or more of the said
elastomers. The elastomer(s) used are also as described above in the
general discussion. The elastomer emulsion, solution or the plastisol used
for the subsequent dipping is compounded, with, apart from the usual
ingredients, most preferably an Aloe vera solution such that preferably
approximately 0.2 to 2.5 phr are in the dry finished glove. The
concentration may be governed by applicable standards. The minimum
concentration for the International Aloe Science Council certification is
15% by weight,
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[0143] The elastomer(s) selected for the bilaminar glove and the
botanical extract for incorporation into at least one layer of the glove are
as
disclosed supra for a bilaminar glove. The preferred elastomer(s),
botanical extract(s) and phr selected for the bilaminar glove may also be
used for malcing a preferred bilaminar flexible elastomer article of the
present invention. Referring now to FIG. 3, a preferred embodiment of a
bilaminar glove 112 having a first layer 114 and a second layer 116. The
elastomer selected for the first layer 114 and for the second layer 116 may
be selected from the group of elastomers including preferably an NRL, a
synthetic polyisoprene, a chloroprene, a PU, an acrylonitrile, a butadiene
methylmethacrylate, an SBS, an SIS, an SEBS, a silicone, an acrylate-based
hydrogel, a PVC, any other elastomer that is suspendable, soluble or
miscible into an emulsion, solution or plastisol, and mixtures thereof. The
botanical extract is suspendable, soluble and/or miscible in the emulsion,
solution or plastisol of the elastomer(s) for the layer of the glove into
which
the botanical extract is incorporated. First layer 114 has an OS 102.
Second layer 116 forms an interior layer of glove 112, having a WCS 104.
Preferably Aloe vera extract 108 and/or Nopal extract 110 are the botanical
extracts compounded with the elastomer(s) forming the second layer 116.
Aloe vera extract and/or Nopal extract is preferably used with a
concentration of approximately 0.2 to 2.5 phr in the finished glove. Most
preferably Aloe vera extract is used with a concentration of approximately
0.2 to 2.5 phr in the fmished glove.
[0144] The elastomers disclosed for the multi-layered gloves and the
botanical extract for incorporation into at least one layer of the glove are
as
disclosed supra for a multi-layer glove. The elastomer(s), botanical
extract(s) and phr selected for the multi-layered glove may also be used for
making a preferable multi-layered flexible article of the present invention.
58
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101451 FIG. 4 illustrates the botanical extract(s) incorporated into the
innermost layer and FIG. 22 illustrates the botanical extract(s) incorporated
into a non-innermost layer of the multi-layer glove. Referring next to FIG.
4, a preferred embodiment of a multi-layer glove 120 has a first layer 114;
an innermost layer 122 and a second (or more layer) 124 disposed between
the first layer 114 and innerrnost layer 122. The elastomer(s) for each layer
of the glove 114, 112, 124 may be selected from the group of elastomers
including preferably an NRL, a synthetic polyisoprene, a chloroprene, a
PU, an acrylonitrile, a butadiene methylmethacrylate, an SBS, an SIS, an
SEBS, a silicone, an acrylate-based hydrogel, a PVC, any other elastomer
that is suspendable, soluble or miscible into an emulsion, solution or
plastisol, and mixtures thereof. The botanical extract is suspendable,
soluble and/or miscible in the emulsion, solution or plastisol of the
elastomer(s) for the layer of the glove into which the botanical extract is
incorporated. The botanical extracts, Aloe vera extract 108 and/or Nopal
extract 110 are preferably at least compounded with the elastomer(s) of the
innermost layer 122 and may be compounded with elastomer(s) of the
second or more layers 124. The selected elastomer(s) used are preferably
compounded with a Nopal extract and/or Aloe vera extract with a
concentration of approximately 0.2 to 2.5 phr in the finished glove. Most
preferably an Aloe vera extract is used, with a concentration of
approximately 0.2 to 2.5 phr in the finished glove.
101461 Referring now to FIG. 22, glove 121 an alternate embodiment of
the multi-layer glove 120 of FIG. 4 is shown. Glove 121 has a first layer
114; an innermost layer 122, and a second (or more layer) 124 disposed
between the first layer and the innermost layer 122. The first layer 114, the
innermost layer 122 and the second/or more layer 124 are made of
elastomer(s) preferably as disclosed for multi-layer glove 120 supra.
Preferably the botanical extract(s), Aloe vera extract 108 andlor Nopal
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extract 110 are compounded with the elastomer(s) of second (or more)
layer 124. The elastomer(s) are preferably compounded with Nopal extract
and/or Aloe vera extract in a concentration between approximately 0.2 to
2.5 phr (botanical extract to elastomer) in the finished glove. Most
preferably an Aloe vera extract is used with a concentration of
approximately 0.2 to 2.5 phr in the finished glove.
[0147) The second aspect of the present invention includes applying a
non-Aloe vera coating material (hereinalso "coating material") to at least a
wearer contacting surface of a flexible article. The non-Aloe vera coating
material contains a non-Aloe vera botanical extract having a mucinous
polysaccharide. The non-Aloe vera botanical extract has moisture
homeostasis capabilities, thixotropic properties of a liquid biopolymer, and
serves as a lubricant, donning agent, providing moisturizing properties and
contains therapeutic components that impart one or more of wound healing,
anti-inflammatory, anti-microbial, analgesic, and anti-aging properties.
The non-Aloe vera coating material may be selected from the group of non-
Aloe vera botanical extracts including preferably non-Aloe vera botanical
extracts of Nopal, okra, kelp, tamarind, psyllium, carrageenan, chia, flax,
carob, guar, xanthan, konjac, cassia, tara, karaya, ghatti, tragacanth,
glucomannan, galactomannan, non-Aloe vera laboratory produced
polysaccharides, and mixtures thereof. Additional non-Aloe vera additives
may be included in the non-Aloe vera coating material; these additives
include Vitamin E, Vitamin A, Vitamin C, Vitamin B3, Vitamin B5, jojoba,
rose hips, tea tree oil, flax seed oil, palm oil, acetylsalicylic acid, and
mixtures thereof. The aforementioned non-Aloe vera botanical extracts
and additives are commercially available or prepared by known in the art
techniques, as discussed supra. Preferably the coating material contains a
Nopal extract. Most preferably the coating material contains both Nopal
and Vitamin E. The non-Aloe vera coating material is applied to the
CA 02448475 2003-11-07
flexible article using conventional spray, dipping, tumbling, or soaking
processes. Typically a 5% to 20% solution (water andlor ethanol) of the
non-Aloe vera botanical extract is applied, but may range from 1% to 50%
solution (based on a 100:1 powder of non-Aloe vera botanical extract).
[0148] The percentage range of coating materials selected is sufficient to
accommodate existing flexible article formulas and machine
configurations. For example, when using an oven to dry coating materials,
a longer existing oven time would favor a more dilute concentration of the
non-Aloe vera botanical extract in the coating material because of the
additional time to evaporate the excess water.
[0149] The following FIGs. 5-7 illustrate the surface coating is applied to
single, bilaminar, and multi-layered gloves. The non-Aloe vera coating
material of the present invention may also be applied to a single layer or a
multi-layer or a bilaminar flexible article as included in the present
invention. FIGs. 5-7 illustrate an aspect of the invention wherein the non-
Aloe vera coating material is coated on the interior surface of the glove,
e.g. the wearer contacting surface of the glove. Preferably a 5% - 20%
solution of the non-Aloe vera botanical extract is used in FIGs. 5-7. The
solution is dried after application.
[0150] Referring now to FIG. 5, a single layer glove 130 having a
preferred interior surface non-Aloe vera botanical coating of Nopal extract
110 is illustrated. Glove 130 has a single layer 132, made from an
elastomer(s) selected from the group of elastomers including preferably an
NRL, a synthetic polyisoprene, a chloroprene, a PU, a PVC, an SBS, an
SIS, a silicone, a butadiene methylmethacrylate, an acrylonitrile, an SEBS,
an acrylate-based hydrogel, any other elastomer that is suspendable,
soluble or miscible into an emulsion, solution or plastisol, and mixtures
thereof. Any other elastomer material or combination of elastomer
materials suitable for forming a single layer glove may be used to make
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single layer glove 130. Single layer 132 has an outer surface OS 102 and
an opposite coating surface 134, (e.g., the wearer contacting surface of an
uncoated glove). A surface coating of Nopal extract 110 is preferably
applied to coating surface 134 forming coating layer 136. Thus, a wearer
contacting surface (WCS) 104 is coated with Nopal extract 110. The
application of the coating is done using a spray, dipping, tumble or soaking
process.
[01511 Referring next to FIG. 6, a bilaminar glove 140 having a preferred
interior surface non-Aloe vera coating of Nopal extract 110 is illustrated.
Bilaminar glove 140 has a first layer 114 and a second layer 116. The
elastomer (or elastomers) selected for the first layer 114 and the second
layer 116 are preferably an elastomer selected from the group of
elastomers, including an NRL, a synthetic polyisoprene, a chloroprene, a
PU, an acrylonitrile, a butadiene methylmethacrylate, an SBS, an SIS, an
SEBS, a silicone, an acrylate-based hydrogel, a PVC, any other elastomer
that is suspendable, soluble or miscible into an emulsion, solution or
plastisol, and mixtures thereof. Any other elastomer material or
combination of elastomer materials suitable for forming a bilaminar glove
may be used to make bilaminar glove 140. First layer 114 has an OS 102.
Second layer 116 forms an interior layer of glove 112, having a WCS 104.
First layer 114 has an OS 102. The second layer 116 has an interior
coating surface 142 (e.g., the wearer contacting surface of an uncoated
glove). Preferably a surface coating of Nopal extract 110 is applied to the
coating surface 142 forming a coating layer 144. The non-Aloe vera
coating is preferably applied onto the inner surface of the gloves by
spraying, dipping, tumbling or soakking. Thus, a wearer contacting surface
(WCS) 104 is coated with coating layer of Nopal extract 110.
[0152] Referring now to FIG. 7, a multi-layer glove 150, preferably
having an interior surface non-Aloe vera coating of Nopal extract 110, is
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illustrated. Glove 150 is similar to glove 120 in FIG. 4 having a first layer
114, and an innermost layer 122 and a second (or more) layer 124. The
innermost layer 122 is disposed toward an interior of the glove 150. First
layer 114 has OS 102. Innermost layer 122 has a surface 152 for receiving
a coating. Preferably a non-Aloe vera coating of Nopal extract 110 is
applied to surface 152 by using a spray, dipping, tumble process, or
soaking. Thus, the coating forms a coating layer 154 forming a wearer
contacting surface 104 of glove 150. Preferably the elastomer(s) for each
layer (114, 122, 124) of the glove includes one or more of an NRL, a
synthetic polyisoprene, a chloroprene, a PU, an acrylonitrile, a butadiene
methylmethacrylate, an SBS, an SIS, an SEBS, a silicone, an acrylate-based
hydrogel, a PVC, any other elastomer that is suspendable, soluble or
miscible into an emulsion, solution or plastisol, and mixtures thereof. Any
other elastomer material or combination of elastomer materials suitable for
forming a multi-layer glove may be used to make multi-layer glove 150.
101531 A third aspect of the invention includes a botanical extract
incorporated in an elastomer layer forming the flexible article and a non-
Aloe vera coating material being coated preferably on at least the wearer
contacting surface of the flexible article. The elastomer(s) used for the
flexible article are any of the aforementioned elastomer(s) discussed with
reference to FIGs. 2-4; the botanical extract for incorporation into an
elastomer layer forming the flexible article and the non-Aloe vera coating
material used on the wearer contacting surface of the flexible article are
those previously discussed supra. FIGs. 8-10 and 23 illustrate this with
respect to a glove. However, as one of ordinary sldll in the art will
appreciate, the present invention comprehends making single, bilaminar,
and multi-layered flexible articles with a botanical extract incorporated into
at least one layer and providing a surface non-Aloe vera coating material on
preferably at least the wearer contacting surface; this is shown by the
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combination of FIGs. 11 and 12. The elastomer(s) compounded with
botanical extract(s), the botanical extracts(s) and the non-Aloe vera coating
materials selected for the single, bilaminar and multi-layer elastomeric
gloves disclosed supra and below may also preferably be used to make the
single layer, bilaminar and multi-layer flexible articles of the present
invention.
101541 Referring next to FIG. 8, a single layer glove 160 preferably has a
botanical extract both within the glove layer and a non-Aloe vera coating
material as an interior coating. The structure of glove 160 is similar to that
in association with FIG. 5, wherein like numbers refer to similar parts.
Glove 160 has a single layer 132 having an OS 102 and an opposite coating
layer surface 134 for depositing a surface coating layer 136 thereon. Layer
132 is made from an elastomer compounded with a botanical extract of the
present invention. Preferably the elastomer may be selected from the group
of elastomers including preferably an NRL, a synthetic polyisoprene, a
chloroprene, a PU, an acrylonitrile, a butadiene methylmethacrylate, an
SBS, an SIS, an SEBS, a silicone, and an acrylate-based hydrogel, any
other elastomer that can be suspended into an emulsion, and mixtures
thereof. Any other elastomer material or combination of elastomer
materials suitable for forming a single layer glove and into which the
botanical extract is suspendable, soluble or miscible may be used to make
single layer glove 160. Preferably the botanical extract selected for
compounding with the elastomer is Aloe vera extract 108 and/or Nopal
extract 110, (most preferably Aloe vera extract 108 is used) in the preferred
phr amounts described in association with FIG. 2. The coating layer
surface 134 is coated with a non-Aloe vera coating material, most
preferably a Nopal extract (preferably 5% to 20 iu solution) using a spray,
dipping, tumble, or soaking process forming coating layer 136.
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[0155] Referring now to FIG. 9, a bilaminar glove 170 is constructed
similar to glove 140 in FIG. 6 where like numbers refer to similar parts. A
first layer 114 and a second layer 116 are preferably made from one or
more elastomers. The elastomer or elastomers for each layer 114, 116
may be selected from the group of elastomers including preferably an NRL,
a synthetic polyisoprene, a chloroprene, a PU, an acrylonitrile, a butadiene
methylmethacrylate, an SBS, an SIS, an SEBS, a silicone, an acrylate-based
hydrogel, a PVC, any other elastomer that is suspendable, soluble or
miscible into an emulsion, solution or plastisol, and mixtures thereof. Any
other elastomer material or combination of elastomer materials suitable for
forming a bilaminar glove may be used to make a layer of glove 170 that
does not contain the botanical extract. Any other elastomer material or
combination of elastomer materials suitable for forming a bilaminar glove
and into which the botanical extract is suspendable, soluble or miscible
may be used to make the layer or layers of glove 170 into which the
botanical extract is incorporated. A botanical extract of the present
invention is compounded with the elastomer(s) selected for the layer(s) of
the glove into which the botanical extract is to be incorporated. The
botanical extract is suspendable, soluble or miscible in the emulsion,
solution or plastisol of the elastomer for the selected layer 114, 116 of the
glove into which the botanical extract is to be incorporated. The botanical
extract is preferably an Aloe vera extract or a Nopal extract or both.
Preferably Aloe vera extract 108 and/or Nopal extract 110 (and most
preferably Aloe vera extract 108 is used) are added to the second layer 116.
The preferred amounts (phr) of botanical extract is as disclosed in
association with FIG. 3. First layer 114 has OS 102. Second layer 116 has
a coating layer surface 142. The coating layer surface 142 is coated with a
non-Aloe vera coating material, preferably a Nopal extract 110 (preferably
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in a 5% to 20% solution) using a spray, dipping, tumble, or soaking process
forming coating layer 144 which provides a wearer contacting surface 104.
[0156] FIGs. 10 and 23 illustrate a multi-layer glove having a botanical
extract within at least one layer and having a non-Aloe-vera coating
material on the wearer contacting surface. Referring next to FIG. 10, a
multi-layer glove 180 similar to glove 150 in FIG. 7 where like numbers
refer to similar parts, is illustrated. A multi-layer glove has a first layer
114, an innermost layer 122 and a second (or more) layer 124,
therebetween. Innermost layer 122 is disposed toward an interior of the
glove 180. The elastomer(s) selected for each layer of the glove may be
selected from the group of elastomers including preferably an NRL, a
synthetic polyisoprene, a chloroprene, a PU, an acrylonitrile, a butadiene
methylmethacrylate, an SBS, an SIS, an SEBS, a silicone, an acrylate-based
hydrogel, a PVC, any other elastomer that is suspendable, soluble or
miscible into an emulsion, solution or plastisol, and mixtures thereof. Any
other elastomer material or combination of elastomer materials suitable for
forming a multi-layer glove may be used to make a layer or layers of glove
180 that do not contain the botanical extract. Any other elastomer material
or combination of elastomer materials suitable for forming a multi-layer
glove and into which the botanical extract is suspendable, soluble or
miscible may be used to make the layer or layers of glove 180 into which
the botanical extract is incorporated. A botanical extract of the present
invention is compounded with the elastomer(s) selected for the layer(s) of
the glove into which the botanical extract is to be incorporated. The
botanical extract is suspendable, soluble or miscible in the emulsion,
solution or plastisol of the elastomer selected for the layer(s) of the glove
into which the botanical extract is to be incorporated. Preferably Aloe vera
extract 108 andJor Nopal extract 110 (and most preferably Aloe vera
extract 108) are preferably compounded with the elastomer(s) forming the
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innermost layer 122 and optionally the second (or more) layers 124 in the
preferred amounts (phr's) disclosed in association with FIGs. 4 and 22.
Innermost layer 122 has a coating contacting surface 152. The coating
contacting surface 152 is coated with a coating layer 154 of a non-Aloe
vera coating material, preferably Nopal extract 110 (preferably in a 5% to
20% solution) using a spray, dipping, tumble, or soaking process.
[0157] Referring now to FIG. 23, a multi-layer glove 181 is disclosed.
Glove 181 is similar to glove 180 having first layer 114, innermost layer
122 and a second (or more) layer 124 with innermost layer 122 disposed
toward an interior of glove 151. First layer 114 has OS 102. Innermost
layer 122 has a surface 152 for receiving a coating. Preferably a non-Aloe
vera coating material of Nopal extract 110 (preferably in a 5% to 20%
solution) is applied to surface 152 by using a spray, dipping or tumble
process. The coating forms a coating layer 154 forming a wearer
contacting surface 104 of glove 181. The elastomer(s) used in each layer
of the multi-layer glove includes the elastomer(s) previously listed with
respect to glove 180. A botanical extract of the present invention is
compounded with the elastomer(s) selected for the layer(s) of the glove into
which the botanical extract is to be incorporated. Preferably Aloe vera
extract 108 andlor Nopal extract 110 (most preferably Aloe vera extract
108 is used) are added to at least one layer, in this instance the second
layer
124. The concentration of botanical extract to elastomer (phr) in the
finished glove 181 is preferably as described in association with FIGs. 4
and 22.
[0158] The quantity of the botanical extract to incorporate into the
elastomer matrix of the glove shown in FIGs. 2-4, 8-10, and 22-23 is
sufficient to confer: a lower modulus of the glove similar to NRL without
removal of laticifer cell content, antioxidant protection of the glove,
colloidal stabilization of the elastomer emulsion of the matrix material of
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the glove, emulsification enhancement and thixotropic properties providing
uniformity of the glove thickness. The botanical extract(s) are
commercially available or can be manufactured by known in the art
processes (supra).
[0159] In summary, for FIGs. 2-4, 8-10 and 22-23, the elastomer(s)
(which are suspended in an emulsion or, suspendable, soluble or miscible
in the solution or the plastisol) are compounded with a botanical extract,
preferably an Aloe vera extract and a Nopal extract, most preferably an
Aloe vera extract, in a quantity sufficient to have between approximately
0.2 to 2.5 phr of the botanical extract to elastomer in the finished glove,
(or
other flexible elastomer article) to produce a target finished product ratio
of
between approximately 0.2 to 5.0 phr. The concentration of botanical
extract to parts per hundred of elastomer may range from approximately
0.2 to 2.5 phr or higher in the finished glove (or other finished flexible
elastomer article). The quantity of botanical extract selected is sufficient
to
ensure that physical properties required by ASTM and/or ISO
specifications supra (or other flexible article performance standards) are
not exceeded for tensile strength, modulus, ultimate elongation and aging
properties.
[0160] In summary, as illustrated in FIGs. 5-7, 8-10 and 23, and for other
flexible elastomer articles, for the non-Aloe vera botanical coating (surface
coating mixture), the concentration range of the non-Aloe vera botanical
extract used is a 5% to 20% solution (water and/or ethanol), but may be
prepared in a 1% to 50% solution. More preferably an 8% to 12% solution
of non-Aloe vera botanical extract is used; most preferably a 10% solution
is used. Alternatively, for the non-Aloe vera coating material, the non-Aloe
vera botanical extract may also be expressed in units of phr of the non-Aloe
vera botanical extract per hundred weight of elastomer in the finished
product. The phr for the coating material may be determined by industry
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standards or guidelines for a particular non-Aloe vera botanical extract in
the finished flexible elastomer article. The percentage concentration (or
phr) of the non-Aloe vera botanical extract depends upon the type of
application to the article and/or the drying conditions. Preferably the non-
Aloe vera botanical extract selected is Nopal extract. The additive(s) may
be added in usual amounts known in the industry. Preferably the additive
selected to be added to the non-Aloe vera botanical extract is Vitamin E.
[0161] As best shown in FIG. 11, the present invention also comprehends
the method of making a flexible article having one or more layers of an
elastomer and having a botanical extract of the present invention
incorporated into at least one layer of the elastomer. The method of
making the flexible elastomer article include the steps of compounding the
botanical extract with one or more elastomers in an elastomer emulsion,
solution or plastisol. The botanical extract is suspendable, soluble or
miscible in the emulsion solution or plastisol. The botanical extract when
added to the emulsion is characterized by the properties of stabilizing the
emulsion of the elastomer used in forming the article, lowering the modulus
of the elastomer, allowing for a more uniform deposition of film when
forming the article, providing anti-oxidant protection to the finished
article,
and modifying the rheology of the flexible article by decreasing unwanted
flow of the elastomer emulsion when forming the article.
[0162] In FIG. 11, Step 11.1, the article is prepared according to standard
techniques prior to elastomer dipping, molding, or extruding.
[0163] In Step 11.2 a layer of an elastomer compounded with a botanical
extract of the present invention for the flexible article is formed by
dipping,
molding, or extruding. The elastomer solution, emulsion, or plastisol is
prepared (compounded) according to standard processes in the industry.
The botanical extract is incorporated into (compounded with) the emulsion,
solution, or plastisol. When the article is dipped, article formers are
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typically used. Typically for gloves and other flexible articles, formers are
dipped into a tank containing the elastomer with the emulsion, or solution,
or plastisol compounded with the botanical extract. For some devices, like
a cervical cap, a mold is filled with the compounded elastomer (emulsion,
solution, or plastisol) with the botanical extract as appropriate. In other
applications for flexible articles, the elastomer emulsion or solution or
plastisol compounded with the botanical extract is extruded.
[0164] In Step 11.3, after the dipping, filling, or extruding step is
performed, vulcanization, polymerization, curing, evaporating
solvent/drying, and/or fusing the elastomer compounded with the botanical
extract, occurs as is appropriate.
[0165] Step 11.3 incorporates the botanical extract into the elastomer.
Typically for emulsions of elastomers, the incorporation of the botanical
extract into the elastomer matrix occurs by vulcanization or
polymerization. For elastomers that are suspendable, miscible or soluble in
a solution, the incorporation of the botanical extract into the elastomer
matrix usually occurs by evaporation of the solution. Typically for
plastisol suspendable, soluble or miscible elastomers, the incorporation of
the botanical extract into the elastomer matrix occurs by fusing the
plastisol. The elastomer with the botanical extract therein is now disposed
in a layer of the article (this is also referred to herein as incorporating
the
botanical extract into the elastomer matrix). Steps 11.1-11.3, for the
flexible article are repeated for each layer of the article into which the
botanical extract is to be incorporated. The botanical extract includes
extracts preferably selected from the group of extracts of Aloe vera, Nopal,
okra, kelp, tamarind, psyllium, carrageenan, chia, flax, carob, guar,
xanthan, konjac, cassia, tara, karaya, ghatti, tragacanth, glucomannan,
galactomannan, a laboratory produced polysaccharide, and mixtures
(combinations) thereof. In the preferred embodiment, the botanical extract
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consists of Aloe vera and/or Nopal. In the most preferred embodiment
Aloe vera extract is selected. The phr are as described supra for the
incorporation of the botanical extract into one or more elastomer layers.
As is appreciated by those skilled in the art, the method of making flexible
elastomer articles may be generalized to articles other than gloves.
[0166] In addition to making the flexible elastomer articles with the
botanical extract incorporated therein, the present invention also
comprehends the step of applying a non-Aloe vera coating material to the
wearer contacting surface of an article, as shown in FIG. 12. The non-Aloe
vera coating material, of the present invention, is a non-Aloe vera botanical
extract, e.g., a non-Aloe vera mucinous botanical extract or laboratory
produced polysaccharide. The non-Aloe vera coating material is a non-
Aloe vera botanical extract as disclosed, supra, having thixotropic
properties of a liquid biopolymer, moisture regulating properties,
lubricating and moisturizing properties and therapeutic components. The
therapeutic components include one or more of wound healing properties,
anti-inflammatory properties, anti-microbial properties, analgesic
properties, and anti-aging properties. The non-Aloe vera coating material
is prepared as described above by preferably selecting a non-Aloe vera
botanical extract(s), e.g., preferably from the group of extracts of Nopal,
okra, kelp, tamarind, psyllium, carrageenan, chia, flax, carob, guar,
xanthan, konjac, cassia, tara, karaya, ghatti, tragacanth, glucomannan,
galactomannan, a non-Aloe vera laboratory produced polysaccharide and
mixtures thereof, having the aforementioned properties. In addition to the
non-Aloe vera botanical extract, the non-Aloe vera coating material may
contain one or more non-Aloe vera additives (also "additives") selected
from Vitamin A, Vitamin E, Vitamin C, Vitamin B3, Vitamin B5, jojoba,
rose hips, tea tree oil, flax seed oil, palm oil, acetylsalicylic acid, and
mixtures thereof. The additives are selected in customary concentrations.
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The non-Aloe vera coating material (also "coating material") is applied by
spraying, dipping, spray tumbling, or soalcing and in the percent
composition and/or phr for coating material as described supra. The
coating material is solidified preferably by drying to the wearer contacting
surface of the article. The coating material is mechanically and non-
covalently linked to the elastomer material with the non-Aloe vera
botanical extract disposed thereon.
[0167] As described previously herein, the non-Aloe vera coating
material of the present invention may be applied to any flexible article (see
FIGs. 5-7 and 21 for gloves) (not necessarily just the flexible article of the
present invention) having at least one elastomer layer and having a wearer
contacting surface and a distal surface disposed distal to the wearer
contacting surface. The flexible elastomer article has at least one layer of
elastomer between the wearer contacting surface and the distal surface.
The non-Aloe vera coating material containing the non-Aloe vera botanical
extract is applied to the wearer contacting surface or to the distal surface
or
to both. Preferably the coating material is applied to the wearer contacting
surface. For certain articles such as condoms, the coating material may be
applied to both surfaces. The coating material has the aforementioned
properties and contains the aforementioned non-Aloe vera botanical
extract(s); and the aforementioned additives (supra) may be added.
[0168] The flexible articles to which the non-Aloe vera coating material
may be applied include a glove, a catheter, a stent, an incontinence device
having a sheath or sheath-type construction, a condom, a cervical cap, a
diaphragm, an elastomer sheet, a finger cot, a sheath for use with a medical
device or a balloon for use with a balloon catheter, a urinary catheter, a
rectal catheter, a feeding tube, an endotracheal tube, or a cardiac catheter.
[0169] The method of applying the non-Aloe vera coating material
includes a Step 12.1 of preparing a flexible article after vulcanizing,
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polymerizing, evaporating solvent, and/or fusing, etc., to receive a coating
material applied to the wearer contacting surface or to the distal surface, or
to both. Then, in Step 12.2, the non-Aloe vera coating material of the
present invention is applied by having the article dipped, sprayed, tumble
sprayed, or soaked so the non-Aloe vera coating material is disposed on a
selected surface (wearer contacting surface or distal surface or both) of the
flexible article. In Step 12.3, the coating material is solidified preferably
by drying on to the selected surface of the flexible article.
[0170] To prepare flexible elastomer articles of the present invention
having both a botanical extract incorporated into one or more layer(s) and a
non-Aloe vera coating material applied to a surface, the methods described
in FIGs. 11 and 12 are used.
[0171] As will be described now, preferred methods of inaking gloves of
the present invention will be disclosed in FIGs. 13-21. The general method
of making gloves of the present invention is disclosed in Figure 13. The
methods of coating the flexible articles and making flexible articles
according to the present invention can be understood from the specific
examples of the gloves herein, and generalized to other flexible articles.
[0172] The process of making gloves of the present invention may be
more generalized, as shown in FIG. 13. FIG. 13 corresponds to the
discussion regarding gloves shown in FIGs. 2-4, 8-10, 20 and 22-23.
Referring to FIG. 13, in Step 13.1 the process of glove making of the
present invention utilizes customary glove making procedures prior to
dipping the formers into an elastomer compounded with the botanical
extract. In Step 13.2, the botanical extract (preferably Aloe vera 108
and/or Nopal 110) is compounded with elastomer(s) and the formers are
dipped into the compounded elastomer. The composition of the Aloe vera
extract 108 and/or the Nopal extract 110 are as disclosed supra, preferably
about 0.2 to 2.5 phr in the finished product.
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[0173] In Step 13.3, the gloves are processed according to usual
techniques, e.g. vulcanization, polymerization, curing, fusing, solvent
evaporation, etc. to form a glove having Aloe vera and/or Nopal or within
the matrix of the elastomer material of the glove. The general process of
FIG. 13, may be used for making single layer gloves, bilaminar gloves and
multi-layer gloves.
[0174] The methods of making gloves of FIGs. 2-4, 8-10, and 22-23 of
the present invention utilize the general prior art glove making methods,
but add a new material, the botanical extract e.g., preferably the botanical
extract of Aloe vera 108 and/or Nopal 110, to be incorporated into the
elastomer matrix of the glove. This is best seen on FIGs. 14, 16, 17, and
19 for most preferably using an NRL dip with Aloe vera incorporated in a
glove elastomer layer.
[0175] FIGs. 14-20 disclose the methods of making disposable gloves
containing both a botanical extract in the elastomer matrix of the glove and
a non-Aloe vera botanical extract (non-Aloe vera coating material) coated
on an interior surface of the glove. In FIGs. 14-19, for a preferred
embodiment, the glove is made from NRL and the botanical extract
incorporated into the NRL matrix is an Aloe vera extract preferably in a
concentration to achieve approximately 0.2 to 2.5 phr in the fmished glove
as previously discussed herein.
[0176] Alternatively, in lieu of NRL, any other elastomer which is
suspendable into an emulsion, or any elastomer that is suspendable, soluble
or miscible in a solvent or plastisol and wherein the botanical extract is
suspendable, soluble or miscible, and mixtures thereof, may be used as
discussed herein.
[0177] Referring generally to FIGs. 14-19, the four most likely
manufacturing methods are depicted. These methods demonstrate as
closely as possible all the likely steps to be taken should any of them be
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adopted for use. They will be summarized into simple steps for
presentation in the following descriptions.
[0178] In FIGs. 15, 16, 18, 19, 20, and 21, the non-Aloe vera coating
material is a non-Aloe vera botanical extract as disclosed supra, by itself,
or with one or more added compounds (non-Aloe vera additives),
including, but not limited to, Vitamin E, Vitamin A, Vitamin C, Vitamin
B3, Vitamin B5, jojoba, rose hip, tea tree oil, flax seed oil, palm oil,
andlor
acetylsalicylic acid. The non-Aloe vera botanical extract is prepared
preferably as a 5% to 20% solution in a water and/or ethanol mixture. The
non-Aloe vera additives are used in concentrations known in the art. For a
batch of 8,000 to 10,000 gloves, 2 kg of a non-Aloe vera botanical extract
is made into a solution. Such a non-Aloe vera botanical extract coating
material solution is preferably applied by spraying in a rotary tumbler in
the case of an off-line application, or as a dipping solution in the case of
an
on-line application mode. For the latter case, depleted solution is
continually topped up with fresh input. Preferably, a 5% to 20% solution
(water and/or ethanol) of Nopal extract is used. Yet, alternatively, a 5% to
20% solution (water and/or ethanol) of one or more of the following
extracts may be used: okra extract, kelp extract, Nopal extract, tamarind
extract, psyllium extract, carrageenan extract, chia extract, flax extract,
carob extract, guar extract, xanthan extract, konjac extract, cassia extract,
tara extract, karaya extract ghatti extract, tragacanth extract,
galactomannan, glucomannan, or a non-Aloe vera laboratory produced
polysaccharide. Alternatively, the amount of non-Aloe vera botanical
extract, used for coating may be also expressed in phr of coating material
based on dry weight of the finished article. The phr of coating material
may be governed by applicable standards. Most preferably Nopal extract
and Vitamin E are used for the non-Aloe vera coating material.
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[01791 In FIGs. 14-19, "START" denotes the start of the Dipping
Operation and "END" denotes the end of the Dipping Operations.
[0180] Referring now to FIGs. 14 and 15, this method of making gloves
of the present invention and applying the coating involves on-line polymer
coating followed by washing and/or chlorination off-line. After drying, the
gloves are inverted inside out, sprayed with the aforementioned prepared
preferred Nopal extract/Vitamin E solution, tumble dried, and re-inverted
back. The dipping operation is illustrated in FIG. 14, and the post-dipping
operation is illustrated in FIG. 15. The term "Operations" also means
"process" or "method".
[0181] FIG. 14 discloses a glove manufacturing method (process) of the
present invention providing a single layer glove having a botanical extract
incorporated into the elastomer matrix of the glove. Specifically, FIG. 14
discloses a preferred dipping operation using a preferable NRL elastomer
having preferably Aloe vera extract incorporated into the elastomer matrix.
However, other elastomers may be used.
[0182] In Step 14.1, the glove formers or molds are washed. In Step
14.2, the molds are water rinsed. In Step 14.3, the molds are dipped in a
standard coagulant mix. In Step 14.4, the coagulant is dried using standard
conditions. In Step 14.5, the molds having dried coagulant thereon, are
dipped in an NRL emulsion compounded with an amount of Aloe vera
extract therein to make a finished product having approximately 0.2 to 2.5
phr of Aloe vera to NRL. In Step 14.6, gelation occurs. A film is
deposited on the formers. The film contains the Aloe vera and the NRL.
In Step 14.7, leaching is done. In Step 14.8, a polymer coating is applied,
preferably silicone is either sprayed or dipped onto the film. In Step 14.9,
the polymer coating is cured. In Step 14.10, the materials are beaded to
form a cuff. In Step 14.11, if silicone is not used, a powder, such as
cornstarch, may be applied. In Step 14.12, the materials on the molds are
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In Step 14.14, the gloves are stripped from the molds. Steps 14.1-14.4, and
14.6-14.14 use known in the art techniques.
[0183] At this point, the gloves of the present invention may be processed
according to standard known in the art, off-line or post-stripping
operations.
[0184] However, in the most preferred embodiment of the present
invention, the gloves are also coated on the interior wearer contacting
surface with a non-Aloe vera coating material, preferably a non-Aloe vera
botanical extract. The said extract is used by itself or with the addition of
an added compound (additive) using an off-line process of the present
invention. FIG. 15 illustrates a preferred off-line process (post dipping
operation) using a preferred mixture of Nopal extract and Vitamin E
(hereinthroughout also, Nopal/Vitamin E).
[0185] Alternatively, gloves made according to standard dipping
procedures may use the method of applying a coating disclosed in FIG. 15
to apply a non-Aloe vera coating material, preferably a non-Aloe vera
botanical extract to the inside wearer contacting surface of the glove.
[0186] Referring now to FIG. 15 in Step 15.1, the gloves undergo
washing and/or chlorination. In Step 15.2, an optional detackifier may be
applied. In Step 15.3, the gloves are inverted. In Step 15.4, the
aforementioned preferred Nopal/Vitamin E solution is spray-tumbled on
the gloves. In Step 15.5, the gloves are tumble dried and re-inverted back.
101871 FIG. 16 discloses the use of powder free coagulant system
coupled with on-line polymer coating of gloves. On-line coating of the
preferred prepared Nopal/Vitamin E mixture is carried out after the post
cure leaching operation. The dipping operation is illustrated in FIG. 16.
[0188] FIG. 16 discloses a glove manufacturing method of the present
invention of providing a single layer glove of the present invention having
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101881 FIG. 16 discloses a glove manufacturing method of the present
invention of providing a single layer glove of the present invention having a
botanical extract in the elastomer matrix of the glove and having a non-
Aloe vera coating material, preferably a non-Aloe vera extract applied to
the interior wearer contacting surface of the glove. More specifically, FIG.
16 discloses a preferred dipping operation using a preferred NRL elastomer
emulsion compounded with a preferred Aloe vera extract, and having a
preferred Nopal/Vitamin E solution applied to the interior wearer
contacting surface of the glove of the present invention. However, other
elastomers may be used.
[0189] In Step 16.1, the glove formers or molds are washed. In Step
16.2, the molds are water rinsed. In Step 16.3, the molds are dipped in a
standard coagulant mix. In Step 16.4, the coagulant is dried using standard
conditions. In Step 16.5, the molds having dried coagulant thereon are
dipped into an NRL emulsion having a sufficient quantity of Aloe vera
extract therein to produce a finished glove having approximately 0.2 to 2.5
parts of Aloe vera per hundred weight of NRL. In Step 16.6, gelation
occurs. A film of the compounded NRL and Aloe vera is deposited on the
molds. In Step 16.7, extensive pre-cure leaching is performed. In Step
16.8, a polymer coating is applied to the materials on the molds. In Step
16.9, the polymer coating is polymerized. In Step 16.10, the materials on
the mold are beaded to form a cuff. In Step 16.11, an optional detackifier
coating is applied. In Step 16.12, the materials on the molds are vulcanized
thereby incorporating the Aloe vera into the matrix of the NRL. In Step
16.13, post-cure leaching is done. In Step 16.14, the molds with the gloves
thereon are dipped or sprayed in the aforementioned preferred non-Aloe
vera coating material, e.g., solution of Nopal/Vitamin E. In Step 16.15, the
gloves are dried, and the preferred Nopal/Vitamin E coating is disposed
within the interior of the glove on the wearer contacting surface. In Step
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16.16, the stripping of the gloves from the molds is the end of the dipping
operation. The gloves are then prepared for shipment.
[0190] FIGs. 17 and 18, disclose on-line chlorination of gloves followed
by washing/chlorination off-line. After drying, the gloves are inverted
inside out, sprayed with the preferred prepared Nopal/Vitaniin E solution,
tumble dried, and re-inverted back right side out. The dipping operation is
illustrated in FIG. 17, and the post-dipping operation is illustrated in FIG.
18.
[0191] FIG. 17 discloses a glove manufacturing method of the present
invention of providing a single layer glove of the present invention having a
botanical extract in the matrix of the elastomer from which the glove is
made. More specifically, FIG. 17 discloses a preferred dipping operation
using a preferred NRL having a preferred Aloe vera extract incorporated
therein. However, other elastomers may be used.
[0192] In Step 17.1, the glove molds are washed using an acidic or a
basic solution to remove residual NRL. In Step 17.2, the molds are water
rinsed. In Step 17.3, the molds are dipped in coagulant. In Step 17.4, the
coagulant is dried on the molds. In Step 17.5, the molds having the dried
coagulant thereon are dipped in an NRL emulsion compounded with an
amount of Aloe vera therein to make a finished glove having between 0.2
to 2.5 parts of Aloe vera per hundred weight of NRL. In Step 17.6,
gelation occurs. A deposited film of Aloe vera and elastomer are on the
molds. In Step 17.7, leaching is done. In Step 17.8, the materials on the
molds are partially cured. In Step 17.9, the materials are beaded to form a
cuff. In Step 17.10, the materials on the molds are partially vulcanized
thereby incorporating the Aloe vera into the NRL matrix. In Step 17.11,
on-line chlorination is done. Chlorination changes the surface of the glove
making it easier for a surface coating to adhere to the surface. In Step,
17.12, the gloves on the molds are treated to a post-chlorination
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neutralization and rinsing step. In Step 17.13, the gloves on the molds are
dried.
[0193] At this point, the gloves may be stripped off the molds in Step
17.14 ending the dipping operation or may be processed according to
standard, known in the art, post dipping operations where the gloves are
stripped off the molds.
101941 However, in the most preferred embodiment of the present
invention, the gloves are also coated on the interior wearer contacting
surface with a non-Aloe vera coating material, preferably a non-Aloe vera
botanical extract. The said extract is used by itself or with the addition of
an added compound (additive) using the post dipping operation of the
present invention.
[0195] FIG. 18 illustrates a preferred post dipping operation using a
preferred mixture of Nopal extract and Vitamin E. Alternatively, gloves
made according to standard glove making procedures may use the
procedure used in FIG. 18 to apply a preferred a non-Aloe vera coating
material, preferably a non-Aloe vera botanical extract to the inside of the
wearer contacting surface of the glove.
[0196] The stripping of the gloves from the molds of Step 17.14 occurs in
the post dipping operation of FIG. 18.
[0197] In Step 18.1, the gloves on the molds undergo washing and/or
chlorination. In Step 18.2, the gloves may be treated with a detackifier;
typically silicone is used. In Step 18.3, water is extracted from the gloves
and/or the gloves are dried. In Step 18.4, a laboratory analysis is
performed when chlorination has occurred to ensure appropriate product
and effluent neutralization. In Step 18.5, the gloves are inverted. In Step
18.6, the aforementioned preferred non-Aloe vera coating material,
preferably a Nopal/Vitamin E solution is sprayed on the inverted gloves. In
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Step 18.7, the gloves are dried and then re-inverted. In Step 18.8, the
gloves are prepared for shipment.
[0198] FIG. 19 discloses the use of powder free coagulant system
coupled with on-line chlorination of the gloves. On-line coating of the
prepared preferred NopaUVitamin E mixture is carried out after the post
chlorination rinsing operation. The dipping operation is illustrated in FIG.
19.
[0199] FIG. 19 discloses a glove manufacturing method of the present
invention providing a single layer glove of the present invention having a
botanical extract in the elastomer matrix of the glove and having a non-
Aloe vera coating material, preferably a non-Aloe vera extract applied to
the interior surface of the glove. More specifically, FIG. 19 discloses a
preferred dipping operation using a preferred NRL elastomer having a
preferred Aloe vera botanical extract incorporated therein, and having a
non-Aloe vera botanical coating material, preferably a Nopal/Vitamin E
solution, applied to the interior wearer contacting surface of the glove.
However, other elastomers may be used.
[0200] In Step 19.1, the glove molds are washed. In Step 19.2, the molds
are rinsed with water. In Step 19.3, the molds are dipped in a coagulant.
In Step 19.4, the coagulant is dried onto the mold. In Step 19.5, the molds
having dried coagulant thereon are dipped into an NRL emulsion having an
amount of Aloe vera extract therein sufficient to make a fmished product
having approximately 0.2 to 2.5 parts of Aloe vera per 100 weight NRL. In
Step 19.6, a gelation occurs and a film of Aloe vera and NRL is deposited
on the mold. In Step 19.7, leaching is done. In Step 19.8, the materials on
the molds are partially vulcanized. In Step 19.9, the materials are beaded
to form a cuff. In Step 19.10, the materials on the molds are vulcanized
thereby incorporating Aloe vera into the NRL matrix. In Step 19.11, an on-
line chlorination procedure is performed. In Step 19.12, the gloves are
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treated to a post-chlorination neutralization rinsing. In Step 19.13, the
gloves are dipped in the aforementioned preferred non-Aloe vera coating
material of a NopallVitamin E solution. In Step 19.14, the gloves are
dried; and in Step 19.15, the gloves are stripped off the molds. The gloves
are then readied for shipment.
[0201] In another embodiment of the present invention, the powder free
process of manufacturing PVC gloves of the present invention uses
polyester with good water solubility for polyurethane epoxy, and a mixture
of methyl-ethyl-ketone, isobutyl-ketene and isopropyl alcohol may be used
to prevent the surface of PVC gloves from deterioration due to corrosion,
so to avoid affecting the appearance and performance of the gloves.
Alternatively, a water based silicone oil (silicone) and a catalyst form a
film coating of a PVC substrate. FIG. 20 discloses a glove manufacturing
method of the present invention providing a bilaminar glove having a
botanical extract in the elastomer matrix of the glove. Specifically, FIG. 20
discloses a preferred dipping operation using a PVC and silicone or PU
elastomer. The silicone or PU preferably has an Aloe vera extract
incorporated in the elastomer matrix.
[0202] In Step 20.1, an oven is prepared for pre-heating glove formers.
In Step 20.2, the polyvinyl chloride (PVC) resin and the phthalate are
compounded and poured into a dip tank (PVC plastisol dip tank). In Step
20.3, the PVC plastisol dip tank accepts the glove formers and the glove
formers are coated with a coating of a PVC plastisol. In Step 20.4, the
glove formers, with the coating of the PVC plastisol, enter a PVC fusion
oven. In Step 20.5, a bead roll cuff is applied to the fused PVC. In Step
20.6, the silicone or polyurethane coating is compounded with a botanical
extract of the present invention. Preferably the botanical extract is Aloe
vera extract in a quantity sufficient to produce a concentration of
approximately 0.2 to 2.5 parts of Aloe vera to one hundred weight of
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silicone or polyurethane. In Step 20.7, the glove formers are dipped into
the silicone or polyurethane dip tank which contains the botanical extract.
In Step 20.8, silicone or PU are polymerized on the surface of the PVC
concurrently with the PVC fusion. The botanical extract is incorporated
into the silicone matrix or the PU matrix. After fusion, in Step 20.9 the
gloves having the botanical extract, Aloe vera, incorporated into one layer
thereof are stripped from the glove formers. Alternatively, in Step 20.10,
the gloves are then coated with a non-Aloe vera coating material,
preferably a non-Aloe vera botanical extract, most preferably a 5% to 20%
solution of Nopal extract to which Vitamin E (in amounts customary in the
art) is added, according to the previously discussed methods of coating
gloves.
[0203] FIG. 21 shows a coating method of the present invention, of
applying a non-Aloe vera botanical extract (non-Aloe vera coating
material) onto a wearer contacting surface of a glove wherein the gloves are
made of SIS and/or SBS and/or SEBS. The preferred non-Aloe vera
coating material is preferably a Nopal extract in the preferred concentration
or phr of coating material to which a Vitamin E is added, as disclosed
supra. Referring now to FIG. 21, the selected elastomer, e.g., SEBS and/or
SIS and/or SBS, and suitable solvent (solution) are compounded in Step
21.1. Glove formers are dipped into a tank of SEBS and/or SIS and/or SBS
in Step 21.2. In Step 21.3, the solvent is evaporated from the elastomer in
a solvent evaporation chamber. The solvent preferably goes to a carbon
bed solvent recovery system in Step 21.3.1. The glove formers then
proceed to a dip tank having SEBS and/or SIS and/or SBS for dipping
either another layer of different elastomer thereon or dipping the same
layer of elastoiner thereon. In Step 21.5, the solvent is evaporated in a
solvent evaporation chamber. The evaporated solvent preferably goes to a
carbon bed for solvent recovery in Step 21.5.1. The formers with the
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selected elastomers therein are moved to a bead roll in Step 21.6 wherein
the cuff of the glove is rolled. In Step 21.7, a non-Aloe vera coating
material, preferably a non-Aloe vera botanical extract of the present
invention, is coated onto the surface of the glove. Preferably a 5% to 20%
solution of Nopal extract is sprayed or dipped on the glove and the gloves
are dried. Most preferably the Nopal solution contains Vitamin E. The
Nopal coating is disposed on the glove layer having the wearer contacting
surface. In Step 21.8, the gloves are stripped from the mold and the glove
making process is completed.
[0204] The dry donning lubricity of gloves of FIGs. 15, 16, 18, 19, 20,
and 21 coated with the prefened non-Aloe vera botanical extract Nopal and
non-Aloe vera additive/Vitamin E mixture is unaffected and even slightly
improved as gauged by the subjective, known in the industry, donning tests.
With a rating of 1 to 5, where 1 is worst and 5 is best, the gloves so coated
have a dry donning lubricity rating of 5. Doubling and tripling the dosage
of NopaUVitamin E on the gloves does not materially affect such a rating.
[0205] Alternatively, the quantity of non-Aloe vera botanical extract used
in the aforementioned gloves is sufficient to overcome the rabber or plastic
blocking and provide adequate lubriciousness when dry donning is used in
the present invention. This is accomplished by using a quantity of non-
Aloe vera botanical extract as a non-Aloe vera coating material such that
the gloves so coated have not greater than 2500g frictional donning forces.
Donning forces may be measured using a prior art load tester, such as
shown in FIG. 24 and testing procedures disclosed in Cote et al., 1998
Jonrnal of Biomedical Materials Research, 43:331-337, page 333 and;
Fisher et al., 1996 Appl. Biomater. 33:291-295, page 292, is O d
in the preseat ffivaation.
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[0206] As best shown in FIG. 24, one prior art way of measuring donning
force is to use a load tester 300. The load tester 300 is not drawn to scale.
The load tester 300 is attached to a calibrated scale 302 which is connected
via electronics 304 to a strip recorder 310. The scale 302 is calibrated
preferably every half hour using various gram and kilogram weights. Scale
302 is fastened to a rigid base 311. The load tester 300 has a ring assembly
312 having two tapered interfitting rings 314, 316 (preferably 125mm
diameter). A cuff 318 of a glove 320 made of elastomer(s) is stretched
over and around tapered ring 314 and engaged between rings 314, 316 of
the load tester 300. Tapered ring 314 is shown in hidden line. A cuff 318
of the medium hand-sized glove 320 is secured between rings 314, 316.
The glove 320 is sized to fit a hand of a subject. Securing the glove 320
between the two rings 314, 316 makes an opening 322 into which the hand
of the subject may be inserted. Tapered ring 314 has edges 324, 326 which
are shown in hidden line. Edge 328 of cuff 318 is also shown in hidden
line. Shading for the elastomer material used for the glove 320 is not
shown to simplify the drawing, but it is to be understood that the glove 320
is made of elastomer materials. The opening 322 exposes a wearer
contacting surface 330 to the hand of the subject for donnability testing.
[0207] The subject inserts his right hand into the opening 322 of the
glove 320 repeatedly under repeatable speed, donning angle and distance
conditions engaging the wearer contacting surface 330. Maximum force is
measured by the scale 302 and recorded on the strip recorder 310. The
force readings are expressed in g(grams) as the maximum force needed to
don the glove, e.g, "g frictional donning force." The gloves of the present
invention are coated with a quantity of non-Aloe vera botanical extract
such that the gloves so coated have not greater than 2500g frictional
donning forces using the aforementioned or equivalent load tester.
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[0208] As is known in the art, for the other flexible articles disclosed
herein, methods similar to the methods of making and coating the gloves
are used. Other flexible articles may be made having one or more
elastomer layers having therein a botanical extract of the present invention,
disclosed supra, preferably Aloe vera extract and/or Nopal extract; and the
flexible articles may also have the non-Aloe vera coating material applied
to either the wearer contacting surface of the article or to the distal most
surface of the article or to both surfaces of the article. For example, where
the flexible article is one of the following: a catheter, a stent, an
incontinence device having a sheath or a sheath-type construction, a
condom, a cervical cap, a diaphragm, an elastomer sheet, a finger cot, a
sheath for use with a medical device, or a balloon for use with a balloon
catheter, a urinary catheter, a rectal catheter, feeding tube, an endotracheal
tube, or a cardiac catheter, the coating material is applied onto the wearer
contacting surface of the flexible article.
[0209] Typically, a standard manufacturing process is followed to
prepare the flexible article to receive the non-Aloe vera coating material of
the present invention onto a selected surface of the article. The non-Aloe
vera coating material is the non-Aloe vera botanical extract of the present
invention disclosed supra with or with the non-Aloe vera additives,
disclosed supra. Preferably, Nopal extract is used as the non-Aloe vera
botanical extract. Preferably, Vitamin E is the additive added to the Nopal
extract. The non-Aloe vera coating material is applied to the selected
surface of the article, preferably corresponding to the wearer contacting
surface, by spraying, dipping, spray tumbling, or soaking, or in other ways
known in the art. The non-Aloe vera coating material is dried onto the
selected surface, preferably the wearer contacting surface of the article.
The article may have the non-Aloe vera coating applied to the distal surface
in a similar manner or it may be applied to both surfaces. For such articles
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as condoms, having a wearer contacting surface and an outer distal surface
with one or more elastomers there between, the non-Aloe vera coating
material is applied to the wearer contacting surface or to the outer distal
surface or to both surfaces. For such articles as condoms, the condom may
also be made having one or more layers of elastomer there between and
having one of the layers of elastomer having a botanical extract of the
present invention incorporated therein.
[0210] Although an exemplary embodiment of the present invention has
been shown and described with reference to particular embodiments and
applications thereof, it will be apparent to those having ordinary skill in
the
art that a number of changes, modifications, or alterations to the invention
as described herein may be made, none of which depart from the spirit or
scope of the present invention. All such changes, modifications, and
alterations should therefore be seen as being within the scope of the present
invention and that the scope of the present invention be limited solely by
the broadest interpretation that lawfully can be accorded the appended
claims.
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