Note: Descriptions are shown in the official language in which they were submitted.
CA 02496328 2005-02-07
PPC-5044-USNP
FLUID MANAGEMENT ARTICLE AND METHODS OF USE THEROF
Cross-Reference to Related Applications
This application claims priority to Application No. 60/543,005 filed on
February
9, 2004.
Field of the Invention
The present invention relates to a thin fluid management article that combines
bulkiness with limited fluid absorbency to achieve a soft, comfortable article
suitable
for daily management of body exudates.
Background of the Invention
Fluid management articles may be disposable absorbent articles, such as,
pantiliners, sanitary napkins, interlabial devices, adult incontinence
devices, bandages,
breast pads, and diapers. These articles typically have a fluid permeable body-
facing
side and fluid impermeable garment facing side and may include a layer for
holding
body exudates, e.g., an absorbent core or non-absorbent core, there between.
Such
articles have traditionally been made from readily available and relatively
inexpensive
materials, such as, absorbent materials, e.g., cotton fibers, wood pulp fluff,
cellulosic
tissue, or wadding, or non-absorbent materials, e.g., foam.
Products that have become popular with consumers include those known as
ultrathins. Ultrathin products are typically used during menstruation and not
for daily
management of body exudates. While ultrathin products absorb the same amount
or a
greater amount of body exudates as a standard sanitary napkin, the caliper,
i.e.,
thickness, of ultrathin products is typically less than standard sanitary
napkins. For
example, the caliper of a typical ultrathin is about 1.5 mm. Such thinness is
achieved in
ultrathin products by the use of superabsorbents, including superabsorbent
polymers
(SAP).
Recently, it has also been found that more and more consumers are wearing
absorbent articles on a daily basis and, therefore, do not require the fluid
absorption
found in ultrathins or in standard sanitary napkins. There is a need in the
market for a
CA 02496328 2005-02-07
thin absorbent article that is comfortable and discrete while having nominal
fluid
management.
tJ.S. Pat. No. 6,440,111 discloses a fluid management article that, in one
embodiment, is absorbent free and capable of collecting fluid within existing
interstitial
spaces or pores. The spaces or pores are formed between non-absorbent fibers
or
within apertures or bosses. In another embodiment, the article has a cover, a
barrier
layer and an absorbent core intermediate the cover and barrier. The core
contains
limited amounts of absorbent material, e.g, 0.7 g. or less. Such articles were
found to
have a caliper of 3 millimeters or less and a flexural resistance of 120 grams
or less.
The low total capacity of this embodiment, i.e., 1.2 grams or less, limits the
usefulness
of this article.
What is lacking in the marketplace is a fluid management article that provides
comfort and discretion for every day use having increased absorption
properties coupled
with a thin, flexible structure.
Brief Descriution of the Drawings
FIG. 1 is a top plan view of an absorbent article according to the invention;
FIG. 2 is a cross-sectional view taken across line A-A of the embodiment shown
in FIG. 1;
FIG. 3 is a top plan view of one embodiment of an absorbent article according
to the invention; and
FIG. 4 is a cross-sectional view taken across line B-B of the embodiment shown
in FIG. 3.
Detailed Description of the Invention
The fluid management article of the present invention has a bulk that
contributes
to softness and comfort but has the caliper of an ultrathin and the absorbent
capacity to
ensure protection during or between menstrual cycles, e.g. for daily use.
As used herein, the term "fluid management article" shall mean a disposable
absorbent article, such as, a pantiliner, sanitary napkin, adult incontinence
device,
breast pad, and, bandage. These articles typically have a fluid permeable body-
facing
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CA 02496328 2005-02-07
side and fluid impermeable garment facing side. Additionally, such articles
may
include an absorbent or non-absorbent core for fluid retention therebetween.
As used herein, the term "absorbent" shall mean any material or composite that
absorbs fluid, especially body exudates.
As used herein, the term "fluid retention" shall mean the ability of a
material to
retain and hold fluid. Absorption of the fluid by the material is not
necessary for the
material to be considered to have fluid retention. Fluid retention may be
accomplished
merely by holding fluid within voids or spaces between fibers, within
apertures,
depression, such as, embossments, and the like.
As used herein, term "SAP" means particles or fibers that are capable of
absorbing many times, at least 10, more preferably 15, and still more
preferably over
15, their weight in fluids or bodily exudates, under a pressure of 0.5 psi.
As used herein, the phrase "weight percent" means weight of substance per
weight of final material as determined under ambient conditions. By way of
nonlimiting example, 10 weight percent absorbent cellulose-based material
means 10
g/m2 cellulose-based material per 100 g/m2 basis weight of total material.
The present invention relates to a fluid management article designed and
configured to be worn adjacent a user's perineum, which is useful for
collecting and/or
absorbing low volumes of bodily fluids. As seen in Figures 1 and 2, fluid
management
article 10 may be any desired configuration in terms of shape and
construction; but,
generally speaking, it includes a cover 20 having body facing surface 22, a
backsheet
or barrier 40 having a garment facing surface 42, and a unitized core
structure 50 .
The fluid management article 10 has a first end portion 24 in opposed to a
second end
portion 26 and a first longitudinal edge 32 opposed to a second longitudinal
edge 34,
wherein the edges connect the two opposed end portions.
Referring to FIG. 2, in this embodiment, the fluid management article includes
a
cover 20 having body facing surface 22 and a barrier 40 having a garment
facing
surface. The cover 20 may have the following, non-limiting configurations, a
nonwoven web, a woven web, an apertured film, an apertured formed film, a
substrate
having flocked fibers thereon, a lamination of multiple layers of films or
fibrous webs
and combinations thereof, or the like. Unitary core structure 50, which is
between
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CA 02496328 2005-02-07
cover 20 and barrier 40, may contain low amounts of absorbent material
dispersed
within the non-absorbent material.
In one particular embodiment of this invention, the fluid management article
10
is shown in Figures 3 and 4. In this embodiment, the fluid management article
10
includes a cover 20 having body facing surface 22 and a barrier 40 having a
garment
facing surface. The cover 20 may have the following, non-limiting
configurations, a
nonwoven web, a woven web, an apertured film, an apertured formed film, a
substrate
having flocked fibers thereon, a lamination of multiple layers of films or
fibrous webs
and combinations thereof, or the like. Unitary core structure 50, which is
between
cover 20 and barrier 40, may contain low amounts of absorbent material
dispersed
within the non-absorbent material. The cover 20 and unitary core structure 50
are
embossed together, or co-embossed, using a pattern of dots 60. In addition,
this
particular embodiment, a series of flowers 90 are embossed on the cover prior
to co-
embossing the cover and the unitary core structure 50.
Cover
The fluid management article 10 of the present invention includes a cover
layer
20 overlaying the absorbent material. The exterior of the cover forms the body-
facing
surface 22 of the disposable absorbent article. As known by those skilled in
the art, the
cover layer 20 may be formed from any fluid pervious material that is
generally
compliant, soft feeling, and non-irritating to the user's skin and permits
fluid to
penetrate to the absorbent core, which retains the fluid. The cover layer 20
generally
functions to transport fluid away from the wearer into the absorbent article.
In this
manner, fluid and moisture are removed from contacting the wearer, thus making
the
wearer feel dry and comfortable. ~n addition to transporting fluid, the cover
layer 20
I may also absorb and/or retain fluid as well.
The cover 20 can be made from any of the materials conventional for this type
of use. Non-limiting examples of suitable materials that can be used as the
cover layer
20 are woven and nonwoven fabrics formed fibers or filaments of cellulose,
polyester,
polyethylene, polypropylene, nylon, rayon fibers and mixtures thereof or the
cover layer
may be an apertured thermo-plastic film and formed films. Other materials used
in
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making covers layer 20 include gauze or any known porous material with a
suitable
body contacting surface, including, but not limited to nonwoven webs, plastic
nets, and
the like. The cover layer 20 could also be made from a fibrous nonwoven
composite of
bicomponent fibers and pulp fluff.
Bicomponent fibers are known in the art and are composed of two polymers
with different melting points. At least a portion of the outer surface of each
bicomponent fiber has the lower melting polymer. The two polymers may be
arranged
such that a cross-section of the fiber shows the two polymers in a side-by-
side array.
Alternatively, the polymers may be positioned in a so-called sheath/core
arrangement,
in which a core of higher melting polymer is surrounded by a sheath of lower
melting
polymer.
The cover may be made by a process of bonding a nonwoven conjugate fiber
web in which heated air, which is sufficiently hot to melt one of the polymers
of the
multicomponent fibers, is forced through the web. This process is referred to
as
through air bonding. The melting and resolidification of the polymer provides
the
bonding between the fibers to integrate the web. The air velocity is typically
between
100 and 500 feet per minute (30 and 152 m/min) and the dwell time may be as
long as 6
seconds. Through air bonding has relatively restricted variability and since
through-air
bonding requires the melting of at least one component to accomplish bonding,
it is
particularly useful in connection with webs of conjugate fibers or those which
include
an adhesive. In the through-air bonder, air having a temperature above the
melting
temperature of at least one of the exposed components is directed through the
web and
into a perforated roller supporting the web. Alternatively, the through-air
bonder may
be a flat arrangement wherein the air is directed vertically downward onto the
web. The
operating conditions of the two configurations are similar, the primary
difference being
the geometry of the web during bonding.
A useful bicomponent fiber is a 2.0 denier, 45 mm long staple fiber made of a
polyester core and a high density polyethylene sheath. Similar fibers
(polyethylene
sheath and polypropylene core) are available as Danaklon ES-C or ES Bico
(Danaklon
A/S, Varde Denmark) or ES Fiber GuangZhou Co. Ltd. (Chisso). Pulp fibers may
be
obtained as IP "'SUPERSOFT" ELM supplied by the International Paper Company
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CA 02496328 2005-02-07
(Memphis, Tennessee), "'RAYFLOC" E-Type Cellulosic Fluff Pulp, (ITT Rayonier),
or
Korsnas Vigorfluf EN White (KorsncAs, Gavle, Finland). Georgia Pacific EF-100,
or
Weyerhauser NB416L, treated or untreated pulp.
The cover layer 20 may optionally be treated with surfactant to manipulate the
hydrophobicity/hydrophilicty thereof to facilitate optimal fluid transport
properties.
The fibers or other materials that make up the cover layer 20 should not
collapse or lose
their resiliency when subjected to body fluid. The fibers may be oriented by a
carding
process and thermally bonded via embossing. The fiber or filament can be
single
_ . . _ . deleted: The fibers preferably
denier or multidenier. , have denier sizes ranging from I to
2 denier, inclusive.
The cover may be a single layer or be made from multiple layers. The thickness
of the cover may vary from about 0.001 inch (0.025 mm) to about 0.200 inch
(5.000
mm), depending on the material chosen. The weight of the body facing layer
material
preferably is between about 5 and about 150 gsm, more preferably between 15
and 50
gsm and most preferably between 25 and 35 gsm. The cover material is
preferably
though air bonded. Low denier fibers are preferred to form the fiber web and
the
temperature of the hot air may be adjusted to bond only the material having
the lower
melting point. This creates a softer and loftier fiber web.
In one embodiment, the cover is a single layer made from a 2d, 45 mm
bicomponent fiber made of a polypropylene core and a high density polyethylene
sheath
having a weight of 30 gsm.
In another embodiment, the cover is a single layer made from 1.Sd, 45 mm
bicomponent fiber made from polypropylene core and high density polyethylene
sheath
having a weight of 25 gsm.
Any material with soft or cloth-like features may also be used for the body
facing layer. Such material includes nonwoven, such as spunlace, woven, and
knitted
materials. Optionally, the material used for the body-facing layer may include
binders,
such as thermoplastic binder fibers and latex binders.
In one embodiment, the cover is a single sheet of material having a width
sufficient to form the body-facing surface of the absorbent article. In
another
embodiment, the cover has at least two layers and is made of materials
described in the
core section.
6
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Formatted
,The cover, whether a single layer or multiple layers, may also retain fluid.--
If a _ _
separate core layer is used, the body facing layer may be longer and wider
than the core
or be of similar size as the core.
(ienerally, the optional cover layer 20 is a single sheet of material having a
width sufficient to form the body-facing surface 22 of the fluid management
article.
The cover layer 20 may be longer and wider than the optional core.
The cover layer 20 may be embossed with shapes within a given area. For
example, a series or a number of features, e.g., circles, triangles, squares,
lines,
honeycomb, diamond, floral, etc. are embossed over the entire length and width
of the
outer surface of web. Each embossed feature has a major and minor axis
extending
therethrough, the major axis length being greater or equal to the minor axis
length. The
embossed features may be in a repetitive pattern. The embossed pattern may
contribute
to the softness and drapeability of the fluid management article. The
embossments may
also serve to hold fluid or to transfer fluid to the core. In an embodiment
shown in
Figure 3, flower 90 is embossed in a pattern on cover 20.
2o Deleted: Mary Anne, let's not
v... _ include transfer layer and cover
transfer layer laminates. ~
Unitary Core Structure
Nonwoven webs are preferred as starting materials to form the unitary core
structure 50. Suitable fibers useful for making such nonwoven webs include
polyolefin,
polyester fibers, bicomponent fibers, and mixtures thereof. Such fibers may be
fusible
fibers.
In one embodiment two materials are oined b throw h air-bondin to form an__ _
Deleted:
jy g. g ___._
integrally formed composite material 55 that can be used in the unitary core
structure
50. In one embodiment, the composite material 55 includes a first material 52
having at
least about SO% non-absorbent fusible fibers interspersed with absorbent
cellulosic
based fiber and a second material 54 having non-absorbent fusible fibers
wherein the
first and second materials are laminated through air through bonding process.
As seen in Figure 4, the fibers making up first material 52 and second
material
54 are preferably of at least two different deniers, such as, 3 and 2 denier
("d") fibers,
respectively. The first material 52 may contain an absorbent fiber, such as,
rayon in
amounts equal to or less than about 25 weight percent unitary core structure
50. In
7
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one embodiment, the first material 52 contains about 0.086 grams of 3.3d, 27
mm rayon
fibers from Danufil V from Acordis Kelheim, GmbH, dispersed throughout 3d, 45
mm
air through bonded bicomponent (polypropylene/polyethylene fibers) web having
a
weight of 25 gsm available from Guang Zhou ES Fiber Co., Ltd. The second
material
54 is a 2d, 45 mm, through air bonded bicomponent fibers
(polypropylene/polyethylene
fibers) web having a weight of 25 gsm available from Guang Zhou ES Fiber Co.,
Ltd.
The two materials 52 and 54 are integrated using heat to form a composite
material 55
having an overall weight of 50 gsm wherein no visible distinction between
materials 52
and 54, i.e, the materials 52 and 54 are integrally joined to form composite
material 55.
Composite material 55 has fluid retention properties.
T'he nonwoven webs used as materials for the composite materials have a basis
weight from about 20 to about 200 grams per square meter ("gsm"), preferably
from
about 25 to about 50 grams per square meter. In one embodiment, the first
material 52
and the second material 54 have basis weight of 25 gsm, respectively, to yield
a
composite material of 50 gsm.
Raw materials, such as, individual fibers, that are used in the manufacture of
the
unitary core structure 50, may optionally be treated with a surface active
agent, e.g., a
surfactant, to render the structure more hydrophilic or hydrophobic as
desired.
The unitary core structure 50 of the present invention may contain any known
absorbent materials including, but not limited to, absorbent fibers, such as,
cellulose
fibers, including, but not limited to wood pulp, regenerated cellulose fibers,
e.g., rayon
and cotton fibers, rayon fibers and the like; other naturally occurring
absorbent
materials, such as, sphagnum or peat moss; and other synthetic absorbent
materials.
Additionally, the unitary core structure 50 may include one or more of the
following:
binders, such as, thermoplastic and latex, odor-controlling compounds, e.g.,
perfumes,
EDTA (ethylenediaminetetraacetic acid), anti-microbial agents, wetting agents,
wetness
indicator material, materials for administering or delivering medicaments,
such as
encapsulated medicaments, and materials for maintaining skin moisture, such as
encapsulated moisturizers.
CA 02496328 2005-02-07
The core may include only materials, such as, a hot melt adhesive containing
fluid absorbing polymers. One example of such a material is disclosed in EP 1
013 291
A1, the disclosure of which is herein incorporated in entirety by reference.
A representative, non-limiting list, of absorbent material useful in the
unitary
core structure 50 includes, but is not limited to, natural cellulosics, such
as, cotton and
wood pulp; regenerated cellulosics, such as rayon and cellulose acetate; peat
moss,
loofa; arid the like. One skilled in the art would readily appreciate that a
blend of two or
more types of absorbent materials may be used to optimize the performance of
fluid
management articles used in varying conditions. The absorbent material may be
uniformly dispersed within the unitary core structure 50, or may alternatively
be placed
in discrete patterns, or in gradients. For example, in an effort to help
reduce side
leakage, absorbent material may be placed in high concentrations around
peripheral
portions of the core.
The unitary core structure 50 may have a blend of absorbent materials and
thermoplastic fibers, for example to provide structural integrity to the
formed structure
or for heat sealability to additional layers, such as a barrier layer film.
Useful
thermoplastic fibers are polyolefins, such as polypropylene and polyethylene
fibers, and
bicomponent fibers. The thermoplastic fibers may be bi-component or multi-
component fibers having a first component having a first melting temperature
and two
or more additional components having different melting temperatures to that of
the first
melting temperature. Bi-component fibers are typically configured sheath-core
or side-
by-side. Suitable bi-component fibers include polyester/polyethylene and
polypropylene/polyethylene.
In one aspect, the present invention can provide a fluid management article
containing at most 12 weight percent of an absorbent material such as
cellulose-based
material.
As previously stated, the cover 20 and unitary core structure 50 may be joined
together by co-embossing. The dots 60 will provide additional fluid retaining
spaces
and may contribute to the overall softness in terms compressibility. One can
calculate
compressibility as follows: thickness of uncompressed material minus the
thickness of
the compressed material (2.5 pounds per square inch) multiplied by 100 and
dividing
9
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the product by the thickness of the uncompressed material. The dots 60 may
also aid in
providing flexibility to the finished article; the embossed dots allow the
article to bend
without surface deformation or wrinkling.
Barrier
The barrier, also called backsheet 40, may be located adjacent to core 50
(shown Figures 2 and 4) and also to the cover 20, especially if the absorbent
core is
smaller than the cover and barrier (not shown). The barrier 40 of the present
invention
is a body fluid impervious material, which is at least substantially
impermeable to
liquids. Its exterior forms the garment-facing surface of the absorbent
article. The
barrier 40 may be any thin, flexible, body-fluid impermeable material, such
as, but not
limited to, a polymeric film, e.g., polyethylene, polypropylene, or
cellophane, or a
normally fluid pervious material that: has been treated to be impervious, such
as
impregnated fluid repellent paper or non-woven material, including nonwoven
fabric
material, or a flexible foam, such as polyurethane or cross-linked
polyethylene.
Optionally, the barrier 40 may be breathable, i.e., permits vapor to
transpire.
Known materials for this purpose include nonwoven materials, monolithic and
microporous films in which microporosity is created by, inter alia, stretching
an
oriented film. Single or multiple layers of permeable films, fabrics, melt-
blown
materials, and combinations thereof that provide a tortuous path, and/or whose
surface
characteristics provide a liquid surface repellent to the penetration of
liquids may also
be used to provide a breathable backsheet.
The fluid management articles of the present invention are intended to manage
low volumes of fluid encountered both menstrually_and intermenstrually, i.e,
daily.
Preferably, the unitary core structure of the various embodiments of the
present
invention have less than 0.1 grams of absorbent fibers, and the fluid
management article
has a total capacity of 6.0 grams or less, as determined by the total capacity
test defined
in the test methods section,
In addition to fluid capacity, the articles of the present invention are
designed to
be extremely comfortable and non-obtrusive to a user. The collective design
attributes
are intended to provide daily confidence without compromise to lifestyle,
including
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activity and clothing. Two variables, which may affect the before mentioned
design
characteristics, are article caliper, compressibility and flexibility.
Preferably the articles
have a caliper of 2.0 millimeters or less, and more preferably 1.5 millimeters
or less.
Flexibility is measured by a flexural resistance test, described in great
detail in the test
methods section. Preferably, the articles have a flexural resistance of about
40 grams or
less, and more preferably about 35 g or less. Preferably the articles have a
compressibility of at least 45% as determined by compressibility test defined
in the test
methods section.
BondinE Methods
The layers of the absorbent article may be, but not necessarily, bonded, e.g.,
glued or adhered, to the adjacent layer. For example, the underside of the
cover 20 may
be adhered to the topside of the absorbent core 50. The underside of the
absorbent core
50 may be adhered to the topside of the barrier layer 40. Any methods known in
the art,
such as, fusion bonding, adhesive attachment, or by any other securement means
can be
used to secure the individual layers together to form the final absorbent
article.
Included within such methods are coembossing, thermobonding, mechanical
bonding,
and the like. Fusion bonding includes heat bonding, ultrasonic bonding, and
the like.
Adhesive is typically used to attach the layers into a single absorbent
article.
For example, in one embodiment, the body facing cover 10 is attached to the
barrier
layer SO with adhesive NW 1023 available from H.B Fuller and Company (St.
Paul,
MN). The adhesive may be applied in any method.
Adhesive may include pressure sensitive adhesive that is applied as strips,
swirls, or waves, and the like. As used herein, the term pressure-sensitive
adhesive
refers to any releasable adhesive or releasable tenacious means. Suitable
adhesive
compositions, include, for example, water-based pressure-sensitive adhesives
such as
acrylate adhesives. Alternatively, the adhesive composition may include
adhesives
based on the following: emulsion or solvent-borne adhesives of natural or
synthetic
polyisoprene, styrene-butadiene, or polyacrylate, vinyl acetate copolymer or
combinations thereof; hot melt adhesives based on suitable block copoylmers -
suitable
block copolymers for use in the invention include linear or radial co-polymer
structures
CA 02496328 2005-02-07
having the formula (A-B)x wherein block A is a polyvinylarene block, block B
is a
poly(monoalkenyl) block, x denotes the number of polymeric arms, and wherein x
is an
integer greater than or equal to one. Suitable block A polyvinylarenes
include, but are
not limited to Polystyrene, Polyalpha-methylstyrene, Polyvinyltoluene, and
combinations thereof. Suitable Block B poly(monoalkenyl) blocks include, but
are not
limited to conjugated dime elastomers such as for example polybutadiene or
polyisoprene or hydrogenated elastomers such as ethylene butylene or ethylene
propylene or polyisobutylene, or combinations thereof. Commercial examples of
these
types of block copolymers include KratonTM elastomers from Shell Chemical
Company,
VectorTM elastomers from Dexco, SolpreneTM from Enichem Elastomers and
StereonTM from Firestone Tire & Rubber Co.; hot melt adhesive based on olefin
polymers and copolymers where in the olefin polymer is a terpolymer of
ethylene and a
comonomers, such as vinyl acetate, acrylic acid, methacrylic acid, ethyl
acrylate, methyl
acrylate, n-butyl acrylate vinyl silane or malefic anhydride. Commercial
examples of
these types of polymers include Ateva( polymers from AT plastics), Nucrel(
polymers
from DuPont), Escor (from Exxon Chemical).
Additionally, dots or depressions 60 formed from the co-embossing allow the
absorbent article to be rolled into a compact structure without the cover
surface
wrinkling. Upon unrolling and removal of the release paper, the absorbent
article does
not retain "memory" of being rolled. In other words, the absorbent article
lays flat or
conforms to the article to which it is placed on, in this instance, the crotch
portion of a
garment such as underwear.
The absorbent article of the present invention may be applied to the crotch of
a
garment by placing the garment-facing surface against the inside surface of
the crotch
of the garment. Various methods of attaching absorbent articles may be used.
For
example, chemical means, e.g., adhesive, and mechanical attachment means,
e.g., clips,
laces, ties, and interlocking devices, e.g., snaps, buttons, VELCRO (Velcro
USA, Inc.,
Manchester, NH), zipper, and the like are examples of the various options
available to
the artisan.
Adhesive may be applied to the garment-facing side of the absorbent article.
The positioning adhesive may be any adhesive known in the art. As a non-
limiting
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example, pressure sensitive adhesive strips, swirls, or waves may be applied
to help
maintain the absorbent article in place. As used herein, the term pressure-
sensitive
adhesive refers to any releasable adhesive, or releasable tenacious means.
Suitable
adhesive compositions, include, for example, water-based pressure-sensitive
adhesives,
such as acrylate adhesives. Alternatively, the adhesive composition may
include rapid
setting thermoplastic "hot melt," rubber adhesives, two-sided adhesive tape,
and the
like.
Where positioning adhesive is used on the garment-facing side of the barrier
layer 40, a release strip may be applied to protect the adhesive on the
absorbent article
prior to attaching the absorbent article to the crotch. The release strip can
be formed
from any suitable sheet-like material that adheres with sufficient tenacity to
the
adhesive to remain in place prior to use but which can be readily removed when
the
absorbent article is to be used. Optionally, a coating may be applied to
release strip to
improve the ease of removing the release strip from the adhesive. Any coating
capable
of achieving this result may be used, e.g., silicone. Because typical release
strips have
memory properties, it is contemplated that while a release strip can be used
with the
rolled disposable article of the present invention, the memory properties of
the
disposable absorbent article of the present invention are separate and
distinct from any
memory properties of the release paper.
Wins
Wings, also called, among other things, flaps or tabs, may also be part of the
absorbent article of the present invention. Wings and their use in sanitary
protection
articles are described in U.S. Patent. No. 4,687,478 to Van Tilburg; U.S.
Patent No.
4,589,876 also to Van Tilburg, U.S. Patent No. 4,900,320 to McCoy, and U.S.
Patent
No. 4,608,047 to Mattingly. The disclosures of these patents are incorporated
herein by
reference in their entirety.
As disclosed in the above documents, wings are, generally speaking, flexible
and configured to be folded over the edges of the underwear so that the wings
are
disposed between the edges of the underwear.
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In addition, there may be one or a plurality of wings incorporated into the
present invention. Where opposed wings are present along the longitudinal
edges of the
absorbent article of the present invention, such wings may be directly opposed
or may
be offset from the wings located along the opposite longitudinal edge of the
absorbent
article.
When present, the wings may preferably be folded inwardly prior to rolling the
disposable absorbent article.
Overwrap
The rolled absorbent article can be maintained in a rolled configuration using
a
wrapper, a ring, a hook and loop system, adhesives and mixtures thereof. For
example,
a wrapper made of standard cellophane or polypropylene films and including any
heat
sealable material may be used.
The overwrap can also be embossed (including microembossing), electronically
altered (including corona discharge treatments), coated (including vapor
deposition, and
sputtering), laminated (including film/nonwoven laminate) and the like.
Optionally, the overwrap may be used as a release strip and as such shall
coating
may be applied to the overwrap to improve the ease of removabilty from the
adhesive.
Any coating capable of achieving this result may be used, e.g., silicone.
In addition, slip agents such as fluid lubricants or solid layers with a
reduced
coefficient of friction may be applied to the overwrap package at any
appropriate
portion of the manufacturing process.
Miscellaneous
Any or all of the cover, absorbent layer, transfer layer, backsheet layer, and
adhesive layers may be colored and/or transparent. Such coloring includes, but
is not
limited to, white, black, red, yellow, blue, orange, green, violet, and
mixtures thereof.
Color may be imparted according the present invention through dying,
pigmentation,
and printing. Colorants used according the present invention include dyes and
inorganic and organic pigments. The dyes include, but are not limited to,
anthraquinone dyes (Solvent Red 111, Disperse Violet 1, Solvent Blue 56, and
Solvent
14
CA 02496328 2005-02-07
Green 3), Xanthene dyes (Solvent Green 4, Acid Red 52, Basic Red 1, and
Solvent
Orange 63), azine dyes (Jet black), and the like.
Inorganic pigments include, but are not limited to, titanium dioxide (white),
carbon black (black), iron oxides (red, yellow, and brown), chromium oxide
(green),
ferric ammonium ferrocyanide (blue), and the like.
Organic pigments include, but are not limited to diarylide yellow AAOA
(Pigment Yellow 12), diarylide yellow AAOT (Pigment Yellow 14), phthalocyanine
blue (Pigment Blue 15), lithol red (Pigment Red 49:1), Red Lake C (Pigment
Red), and
the like.
Also contemplated herein include asymmetrical and symmetrical articles having
parallel longitudinal edges, dog bone- or peanut-shaped, circular, oval and
the like.
The silhouette of the disposable fluid management article of the present
invention may be configured to be used with conventional underwear or may be
configured to conform to thong garments. As used herein, the term thong
includes, but
is not limited to, thong underwear, thong swimming suit bottom, G-strings, Rio
cut
underwear, Rio cut swimming suit bottom, Brazilian cut underwear, Brazilian
cut
swimming suit bottom, and any other garment that exposes the buttocks, having
a
narrow strip of fabric or a cord that passes between the thighs supported by a
waistband,
a waist cord, belt or the garment itself. The fluid management article may
include other
known materials, layers, and additives, such as, foam, net-like material,
perfumes,
medicaments or pharmaceutical agents, moisturizers, odor control agents, and
the like.
The fluid management article can optionally be embossed with decorative
designs.
The fluid management article 10 may be made from any of the processes known
to one of ordinary skill in the art. For example, a continuous length of cover
material
may be laminated to a continuous length of absorbent material. This laminate
may then
be laminated to a backsheet to form a fluid management article. The fluid
management
article can then be rolled up and over-wrapped to form a single unitary or
individual
absorbent article. In another embodiment, the cover is laminated to the
backsheet and
then rolled up and over-wrapped.
In one embodiment of this invention, the fluid management article 10 may be
drapeable, that is having a flexural resistance of about 40g. or less as
tested by the
CA 02496328 2005-02-07
Modified Circular Bend Test, ASTM 4032-82 and as described in USSN 10/025299,
Drapeable Absorbent Article, filed 12/19/01, the contents herewith
incorporated in
entirety by reference. In another embodiment, the fluid management article 10
has a
cover 20, a backsheet 40, and a flexural resistance of less than 35 g.
Once the absorbent article is unrolled and the release paper removed, it can
be
placed onto the user's underwear. This particular embodiment conforms to the
underwear and is not noticeable to the user.
The entire contents of all patents and patent applications listed or described
above are incorporated herein by reference.
Example
Fluid management articles were constructed using the following structures and
steps:
a. 50% 3.3d 27 mm (or specific weight) rayon Danufil V from Acordis
Kelheim, GmbH is dispersed within a blend of 3d 45 mm bicomponent fibers made
of
polypropylene and polyethylene is through air bonded to form a 25 gsm
composite
nonwoven web available from Guang Zhou ES Fiber Co., Ltd. This forms the first
layer of the core. The second layer of the core is a 25 gsm composite nonwoven
web of
hot through air bonded 2d 45 mm PP/PE blend available from Guang Zhou ES Fiber
Co., Ltd. The first layer and second layer are bonded together by through air
bonding
process to form a unitary structure having a final basis weight of 50 gsm.
This unitary
structure forms the core.
b. The cover is formed from a 30 gsm nonwoven through air bonded web
made from 2d 45 mm PP/PE blend. The cover is embossed with a surface pattern
such
as a flower.
c. The barrier is a microembossed white film, 23 gsm,of polyethylene and
polypropylene from - Foshan Huahan Santitary Material Ltd.
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The cover and core are first joined together by adhesive HB Fuller NW 1023
available from H.B Fuller and Company (St. Paul, MN) and then co-embossed at
two
stations--the first station being the holes and the second station is the
flower
embossing.
The cover/core layers are joined to the barrier with adhesive HB Fuller NW
1023
available from H.B Fuller and Company (St. Paul, MN) and the outer perimeter
of the
article is crimped then cut into the desired silhouettes....
Positioning adhesive HB Fuller 1662x or HB Fuller 1138 is placed on the
silicone-coated side of the release film/ overwrap and subsequently
transferred to the
garment facing surface of the barrier then trifolded.
From the foregoing description, one skilled in the art can ascertain the
essential
characteristics of this invention, and without departing from the spirit and
scope
thereof, can make various changes and modifications. Embodiments set forth by
way
of illustration are not intended as limitations on the variations possible in
practicing the
present invention.
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