Note: Descriptions are shown in the official language in which they were submitted.
CA 02584797 2007-04-26
METHODS OF DELIVERING MATERIALS INTO THE SKIN, AND COMPOSITIONS
USED THEREIN
This application is a divisional application of Canadian Patent Application
Number
2,510,933 filed June 13`", 1996 which itself is a divisional of Canadian
Patent Application
Number 2,199,993 filed on June 13th, 1996.
Field of the Invention
The invention relates generally to a method of making skin care products and
to
methods of using such products. This invention also relates to skin care
products which
moisturize the skin and prevent excessive drying of the skin.
This invention further relates to skin care products which are antimicrobial
and
help prevent infection by pathogenic microorganisms, and which mitigate
against the
spread of such pathogens.
In particular, the invention is concerned with formulations for cleansing and
moisturizing skin which are antimicrobial, have a water base, and comprise a
micro-carrier
to deliver materials into the skin. The formulations are free of alcohol,
lanolin, fragrance,
petroleum-based components or animal by-products.
This invention still further relates to skin cleaning products which are
antimicrobial, and non-irritating and non-drying to the skin after frequent
use. The instant
invention further relates to skin moisturizing products which are
antimicrobial, non-
greasy, and which rapidly penetrate the outer layers of the skin, and which
form a shield to
prevent loss of moisture from the skin.
Background of the Invention
Excessive drying of the skin is a common problem which is often the result of
exposure to wind, sun and low humidity, or a combination of these factors.
Frequent
washing of the hands can also result in excessive drying. This is particularly
true if
abrasive soaps, alcohol-based products and other harsh chemicals are used for
cleansing.
Skin that has been excessively dried is not only unsightly, but also tends to
slough
off excessively and to crack, leading to abrasions of the skin surface.
Because the skin
1
CA 02584797 2007-04-26
serves a key role as a physical barrier to the entry of parasites and
pathogens, excessive
drying can lead to a breach of the barrier and infection by pathogenic
bacteria and fungi.
Thus cracks or openings in the skin serve as a portal of entry for pathogens
and potential
pathogens. Even organisms that are normally considered to be non-pathogens can
result in
opportunistic infection in immunologically comprised individuals. Infections
may be mild
or severe and may be localized to the initial site(s) of infection or may be
systemic and
spread throughout the body. Such spread may occur by direct extension to
contiguous
tissues, or by way of the lympahtics and ultimately by way of the bloodstream.
Thus, the frequent application of many prior art skin cleansing compositions
contribute to skin damage, and therefore may indirectly increase the risk of
skin infections.
Many prior art skin moisturizers contain petroleum products which dissolve
latex gloves
as worn by workers in diverse fields, including the health care field.
Similarly, many prior art moisturizers contain animal-derived products, such
as
lanolin. It is known that certain animal-derived products may cause skin
allergies and/or
dermatitis.
Skin care products of the invention of the parent application allow for
frequent use
of the products to protect the skin and prevent damage due to drying. In so
doing, skin care
products under the invention help to prevent infection of the skin itself and
entry of
pathogens through the skin where they may infect underlying tissues.
Skin cleansing products of the invention of the parent application are
formulated
not only to accommodate continued frequent use without causing drying and
cracking of
the skin but also, by the inclusion of one or more antimicrobial agents, to
prevent the
transmission and spread of pathogenic or potentially pathogenic
microorganisms.
Skin care products of the invention of the parent application are formulated
to
implement the absorption of the composition by the skin. In particular, the
skin care
products comprise an absorption implementing micro-carrier material. The
absorption
implementing micro-carrier material of choice is a form of ceramic
hydroxyapatite.
Ceramic hydroxyapatite is in the form of macroporous spheres of predetermined
size
range, and is chemically pure. It is formed by the agglomeration of crystals
or
hydroxyapatite, or 0.05 to 0.10 micrometer size range, into spherical
particles which are
then sintered at high temperature to provide mechanically-, physically- and
chemically-
stable spheres. Ceramic hydroxyapatite which is useful is exemplified by that
2
CA 02584797 2008-01-11
manufactured by the Asahi Optical Company, Tokyo. Ceramic hydroxyapatite has
been
widely used as a chromatographic separation medium (see, for example R. Kasai
et al. J.
Chromatography 407, 205 (1987); S. Tsuri et al. J Immunol. Methods 106, 169
(1988); T.
Kadoya et al. J. Liquid Chromatography 9,3543 (1986); T. Kadoya et al J.
Liquid
Chromatography 11,2951 (1986)).
Apart from ceramic hydroxyapatite referred to above, hydroxyapatite has been
produced in several other fornls, each with a characteristic particle
morphology, size
distribution and surface structure, as observed by scanning electron
microscopy
(T. Kadoya et al. J. Liquid Chromatography 9,3543 (1986).
Hydroxyapatite has also been ascribed various non-chromatographic applications
including in a cosmetic material containing spherical hydroxyapatite, in a
melanin-
lightening composition including ethyl alcohol and sodium hydroxide, the use
of
hydroxyapatite for the selective removal of protein from the body surface, the
use of
hydroxyapatite as an abrasive, to assist in the cleaning of inanimate
surfaces, and its use in
a blending agent, comprising polystyrene beads coated with hydroxyapatite.
SUMMARY OF THE INVENTION
The invention of this application provides a composition of matter for
application
to the skin, said composition comprising: macroporous ceramic hydroxyapatite
particles;
and a physiologically and cosmetically acceptable vehicle other than water,
wherein said
vehicle is formulated for application to the skin.
Skin moisturizing products of the present invention are formulated to protect
the
skin and maintain the skin in a healthy condition. Skin moisturizing products
of the
present invention are also formulated to be antimicrobial, thereby further
reducing the risk
of infection by pathogens. Furthermore, the antimicrobial properties of
moisturizing
products of the invention reduce the risk of transmission of pathogenic and
potentially
pathogenic microorganisms. Skin care products of the instant invention are
further
formulated to rapidly penetrate the skin, whereby ingredients of the
formulation are more
effective.
The compositions and methods of the instant invention may be used to protect
the
integrity of the skin. The compositions and methods of the instant invention
may also be
used to promote and maintain healthy skin. The skin cleansing compositions of
the instant
3
CA 02584797 2008-01-11
invention may be used frequently to prevent the spread of pathogenic or
potentially
pathogenic microorganisms. The skin cleansing compositions of the instant
invention may
also be used frequently on a continual basis with minimal risk of causing
drying, irritation,
inflammation, or damage to the skin. The antimicrobial skin moisturizing
compositions of
3a
CA 02584797 2008-01-11
the instant invention may be used to minimize the risk of irritation and
infection. The skin
cleansing and moisturizing products of the instant invention do not dissolve
latex and are
fully compatible with the use of latex gloves. Thus, the skin moisturizing
compositions of
the instant invention may be used with latex gloves without the risk of
dissolution of the
latex or other damage to the latex barrier.
The methods and compositions of the invention may further be used to implement
the rapid absorption of biologically active components by the skin. In
accordance with one
embodiment of the invention, the skin moisturizing composition may be used as
a single
application, or application may be repeated periodically over an extended time
period as
needed.
In accordance with another method of the invention, a skin moisturizing
composition, under the invention, may be applied specifically or
preferentially to the point
or area of a minor cut, crack, or abrasion of the skin. Such application may
protect the
epidermis and the dermis from further damage and promote healing, and/or
prevent
infection of the skin.
The invention of a related application relates to a moisturizing composition
for
applying to and leaving on human skin, the composition in the form of an
antimicrobial
lotion composition comprising: (a) an amount of triclosan effective to kill
microorganisms
present on the skin; (b) an emollient present in an amount effective to
moisturize the skin;
and (c) a lotion base comprised of a, physiologically and cosmeceutically
acceptable
vehicle wherein said components of said lotion are present in amounts
sufficient to
provide an effective antimicrobial lotion.
The invention of a related application also relates to an antimicrobial lotion
composition for application to skin, comprising: (a) approximately 0.1 to 1.0
wt. %
triclosan; (b) an emollient present in an amount effective to moisturize the
skin, wherein
the emollient is cetyl palmitate, dimethylpolysiloxane, glyceryl
monoricinoleate, glycerin,
glyceryl monostearate, isobutyl palmitate, isocetyl stearate, isopropyl
palmitate, isopropyl
stearate, butyl stearate, isopropyl laurate, hexyl laurate, decyl oleate,
isopropyl myristate,
lauryl lactate, octadecan-2-ol, caprylic triglyceride, capric triglyceride,
polyethylene
glycol, triethylene glycol, sesame oil, coconut oil, safflower oil, isoamyl
laurate,
nonoxynol-9, panthenol, hydrogenated vegetable oil, tocopheryl acetate,
tocopheryl
linoleate, allantoin, propylene glycol, arachis oil, castor oil, isopropyl
linoleate, lauryl
4
CA 02584797 2008-09-08
lactate, myristyl lactate, decyl oleate, myristyl myristate, or a combination
thereof; and (c)
a lotion base comprised of a physiologically and cosmeceutically acceptable
water-based
vehicle, wherein said components of said lotion are present in amounts
sufficient to
provide an effective antimicrobial lotion, the lotion is free of volatile
alcohol, petroleum-
based ingredients and animal by-products and further wherein the lotion is
compatible
with latex gloves.
Compositions of this invention can be used to kill microorganisms on skin.
The invention of the parent application relates to a composition for
delivering at
least one active agent to the skin of a subject, the composition comprising at
least one
pharmaceutically active agent loaded into a chemically pure ceramic
hydroxyapatite micro
carrier and to uses of such a composition for healing of damaged skin.
In preferred embodiments:
(a) ceramic hydroxyapatite particles are macroporous;
(b) chemically pure ceramic hydroxyapatite is in the form of particles having
a
mean diameter of from about 1 to 10 micrometers; and
(c) ceramic hydroxyapatite particles have pores of uniform size and regular
shape,
ranging from about 0.05 to 0.10 micrometers in diameter.
DETAILED DESCRIPTION OF THE INVENTION
The skin or integumentary system is an essential, physiologically and
anatomically
specialized boundary lamina. It covers the entire external surface of the
body. The total
area of skin in an adult is between 1.2 to 2.2 m2, and comprises about 10% of
the total
body mass, making it the largest organ of the human body. Functionally, the
skin acts as
an interface between the intemal and external environment, and fulfills
thermoregulatory,
sensory, and other functions, as well as playing a key role as a highly
effective physical
barrier against infectious agents and dehydration. The skin also acts as a
barrier against
mechanical, chemical, osmotic, thermal and photic damage.
The condition of the skin is generally considered, by medical practitioners
and lay
people alike, to reflect the state of health, age and other aspects of life of
an individual.
Histologically, three major tissue layers are identified. The uppermost layer,
the
epidermis, is a relatively thin stratified squamous epithelium which is itself
composed of
five strata. Subjacent to the epidermis is the dermis, a dense fibroelastic
connective tissue
stroma. The third layer, lying beneath the dermis is the subcutaneous layer
composed of
areolar and fatty connective tissue.
There are three basic cell types in the epidermis: keratinocytes which produce
keratin, melanocytes which are involved in pigmentation, and Langerhans cells
which aid
the immune system by intercepting foreign bodies in the skin. In the epidermis
a mitotic
CA 02584797 2007-04-26
layer at the base provides keratinocytes which continuously replace those shed
at the skin
surface.
The epidermis can be divided into layers according to the stage of maturation
of
keratinocytes within it. These layers are, from deep to superficial, as
follows: stratum
basale, stratum spinosum, stratum granulosum, stratum lucidum and stratum
corneum. The
first three of these layers are metabolically active, while the two upper
layers which have
attained terminal keratinization constitute the cornified zone. Cells of the
stratum corneum
eventually become detached from the epidermal surface and are replaced from
below.
Typically the time taken for a newly-formed keratinocyte to pass to the
surface and be
shed ranges from 45-75 days. However, under certain pathological conditions of
the skin,
turnover rates are much higher. As a result keratinization is incomplete and
the normal
barrier functions of the skin are lost.
The dermis comprises a strong yet flexible layer which consists primarily of
collagen. This layer, which contains nerves, blood vessels, hair follicles,
sebaceous glands
and apocrine glands, fulfills vital roles in thermoregulation and sensory
perception. The
sebaceous glands produce sebum, a natural lipid material which helps to
prevent drying,
cracking and excessive shedding of the outer layers of the skin.
Compositions for cleansing and moisturizing the skin according to the
invention
comprise an antimicrobial agent, an emollient and a micro-carrier in
combinations as
described below.
i. Antimicrobial component
The present invention provides skin cleansing and moisturizing compositions,
comprising an antimicrobial agent which functions to inhibit the growth of
pathogenic or
potentially pathogenic bacteria and fungi, or to kill such organisms. Thus the
antimicrobial
agent may be bacteriostatic, bacteriocidal, fungistatic or fungicidal in its
action.
A preferred antimicrobial agent for use under the invention is Triclosan TM.
This
agent used in the formulation has been found effective against the whole
genera of
microorganisms, (for example: bacteria, fungi, Pseudomonas aeruginosa,
Pseudomonas
capacia, Staphylococcus aureus, Escherichia coli, Candida albicans,
Aspergillus niger,
Salmonella typhimurium, etc. ..). Thus, the antimicrobial component of the
composition is
effective in both preventing infection via the skin and in preventing the
spread and
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CA 02584797 2008-09-08
transmission of pathogenic microorganisms. The antimicrobial agent is normally
present
in an amount of from 0.001-5% by weight, preferably from 0.05-2% by weight,
and more
preferably from 0.1-1% by weight.
ii. Water activity depressant
Compositions according to the invention may also comprise one or more water
activity depressants, the function of which is, in part, to inhibit the growth
of
microorganisms during product storage and to preserve the product. Water
activity
depressants, with or without the inclusion of an antibiotic chemical, help to
prevent the
growth of spoilage organisms. Examples of water activity depressants include
sorbitol,
propylene glycol, sugars, and alkali metal salts, including carboxylates,
halides, and
sulfates. A preferred water activity depressant is sorbitol. The sorbitol
component of the
composition is preferably present in a concentration of from 1-20% by weight,
more
preferably from 1-10% by weight, and most preferably from 1-2% by weight.
iii. Micro-carrier
Compositions under the invention may also comprise one or more micro-carriers.
Ceramic hydroxyapatite under the invention is in the form of macroporous
spheres of
predetermined size range and is chemically pure.
The function of such a micro-carrier is, in part, to implement the uptake of
the product by
the skin. Uptake of the product prevents excessive loss of moisture from the
skin surface
and promotes product contact with the metabolically active cells of the dermis
and
epidermis beneath the comified zone of the stratum lucidum and stratum comeum.
A preferred micro-carrier is ceramic hydroxyapatite. Ceramic hydroxyapatite
also
functions as an unbound/excess lipid remover and antimicrobial function
enhancer.
Ceramic hydroxyapatite used under the invention is a form of chemically pure
calcium
phosphate (molecular formula Ca1 o(PO4)6(OH)2), which is produced as spheres
with a
controlled diameter. Preferably the median diameter of ceramic hydroxyapatite
under the
invention is in the range of 1-10 micrometers, more preferably in the range of
2-6
micrometers. Ceramic hydroxyapatite spheres are manufactured by the
agglomeration of
small crystals (50-100 nm size range) followed by sintering at high
temperature. As a
result of this process, each sphere is porous and can act as a miniature
sponge. This
characteristic of ceramic hydroxyapatite spheres allows it to absorb, carry,
and
subsequently release components of the composition to which it has been bound.
7
CA 02584797 2007-04-26
Ceramic hydroxyapatite having a mean particle diameter in the range of 2-6
micrometers can act as an efficient absorption implementing agent for liquid
phase
materials. The carrier and absorption enhancing properties of ceramic
hydroxyapatite is
due to both its porosity and its affinity for various substances. For example,
ceramic
hydroxyapatite has the ability to bind water, charged molecules, lipids,
proteins, and
nucleic acids. The porous nature of ceramic hydroxyapatite allows it to bind
and then
slowly release a relatively large volume of liquid-phase-bound materials.
Due to the small spherical nature of the ceramic hydroxyapatite particles, it
may
also act as a lubricant.
Conventional (i.e. non-ceramic) hydroxyapatite is known to bind to biological
molecules, including proteins, lipoproteins, lipids and nucleic acids (see,
for example,
D. Josic et al. Biol. Chem. Hoppe-Seyler 372, 149 (1991); K.J. Primes et al.
J.
Chromatography, 236, 519 (1982); S. Hjerten, Biochim. Biophys. Acta, 31, 216
(1959);
G. Bemardi and W.H. Cook, ibid. 44, 96 (1960); R.K. Main et al..I. Am. Chem.
Soc. 81,
6490 (1959); A. Tiselius et al. Arch. Biochem. Biophys. Acta, 65, 132 (1956)).
However,
in comparison to ceramic hydroxyapatite, conventional hydroxyapatite is
produced as
particles which are more irregular in shape and in size, and also more
fragile. Ceramic
hydroxyapatite is also superior to conventional hydroxyapatite in that ceramic
hydroxyapatite spheres are resistant to high temperature and pressure, and are
much more
physically stable than conventional hydroxyapatite. (T. Kadoya et al. J.
Liquid
Chromatography, 9, 3543 (1986). This physical stability allows for the
agitation or mixing
of ceramic hydroxyapatite without disintegration of the particles. Ceramic
hydroxyapatite
is also more stable chemically than conventional hydroxyapatite, being stable
for at least
five years when stored at room temperature in dry or hydrated form.
Because hydroxyapatite binds lipids, see, e.g. K.J. Primes et al. J.
Chromatography, 236, 519 (1982), ceramic hydroxyapatite, under the invention,
may bind
to lipid constituents of the instant compositions, as well as to lipid
components of the skin.
Ceramic hydroxyapatite has the additional advantage in the context of the
present
invention of binding to proteins much more strongly than does conventional
hydroxyapatite. In binding to proteins of the skin, ceramic hydroxyapatite
under the
invention can act as a bridge between the proteins of skin cells and bound
lipids. The
8
CA 02584797 2007-04-26
resulting layer of bound lipid molecules can serve as an effective protective
film to
prevent dehydration of, and damage to, the skin.
Finally, ceramic hydroxyapatite, due to its propensity to bind to biological
molecules, may bind to various surface components of microbial cells and
promote the
immobilization and inactivation of microorganisms.
Ceramic hydroxyapatite is preferably present in compositions under the
invention
at a concentration of from 0.001-10% by weight, more preferably 0.01-5% by
weight, and
even more preferably from 0.05-1% by weight.
iv. Vehicle or Delivery System.
The compositions according to the invention also comprise a liquid, solid or
semi-
solid physiologically and cosmeceutically acceptable vehicle or carrier. A
suitable vehicle,
under the invention, may act variously as a solvent, diluent or dispersant for
the
constituents of the composition, and allows for the uniform application of the
constituents
into the skin at an appropriate dilution. It will be apparent to the skilled
artisan that the
range of possible vehicles is very broad. In general, compositions according
to this
invention may comprise at least one physiologically and cosmeceutically
acceptable
vehicle.
Vehicles that can be used in compositions under the invention may be liquids
or
solids, including emollients, various solvents, powders, and humectants.
Carriers may be
used singly or in combination. Suitable carriers may include, but are not
limited to, the
following examples:
castor oil,
ethylene glycol monobutyl ether,
diethylene glycol monoethyl ether,
corn oil,
dimethyl sulfoxide,
ethylene glycol,
isopropanol,
soybean oil,
glycerin,
soluble collagen,
9
CA 02584797 2007-04-26
zinc oxide,
titanium dioxide,
talc,
Kaolin,
hyaluronic acid.
The active constituents of the skin care compositions according to the
invention
may be soluble or insoluble in a liquid carrier. If the active constituents
are soluble in the
carrier, the carrier acts as solvent for the active ingredient. If the active
constituents are
insoluble in the carrier, they are dispersed in the carrier by means of, for
example, a
suspension, emulsion, gel, cream or paste, and the like. Various oils, such as
vegetable oils
obtained from any of corn, sunflower, safflower, soybean, canola, and the
like, may also
be used as a vehicle, either alone or in combination. Various oils may also be
used in
combination with water following emulsification.
v. Water
In general, compositions according to this invention may comprise water. When
water is used in the invention, preferably the water is deionized. Water is a
preferred
solvent and/or diluent for the active constituents in the compositions of the
present
invention. Water may be used singly or in combination with another solvent
and/or
diluent.
vi. Humectant
Compositions under the invention may optionally comprise one or more
humectants, for example:
dibutyl phthalate,
gelatin,
glycerin,
soluble collagen,
sorbitol,
sodium 2-pyrrolidone-5-carboxylate.
A preferred humectant, under the invention, is glycerin.
CA 02584797 2007-04-26
vii. Emollient
Compositions under the invention may optionally comprise one or more
emollients, for example:
butane-l,3-diol,
cetyl palmitate,
dimethylpolysiloxane,
glyceryl monoricinoleate,
glyceryl monostearate,
isobutyl palmitate,
isocetyl stearate,
isopropyl palmitate,
isopropyl stearate,
butyl stearate,
isopropyl laurate,
hexyl laurate,
decyl oleate,
isopropyl myristate,
lauryl lactate,
octadecan-2-ol,
caprylic triglyceride,
capric triglyceride,
palmitic acid,
polyethylene glycol,
propane-l,2-diol,
stearic acid,
triethylene glycol,
sesame oil,
coconut oil,
safflower oil,
isoamyl laurate,
monoxynol-9,
panthenol,
11
CA 02584797 2007-04-26
hydrogenated vegetable oil,
tocopheryl acetate,
tocopheryl linoleate,
allantoin,
propylene glycol,
arachis oil,
castor oil,
isostearic acid,
palmitic acid,
isopropyl linoleate,
lauryl lactate,
myristyl lactate,
decyl oleate,
myristyl myri state.
viii. Sun Blocking Agent
The compositions, according to the invention, may optionally comprise a sun
blocking agent. A preferred sun blocking agent under the invention is octyl
palmitate.
ix. Anti-inflammatory Agent
The compositions, according to the invention, may optionally comprise an anti-
inflammatory agent. Preferred anti-inflammatory agents, under the invention,
include
extracts of Aloe vera, panthenol, tocopheryl acetate, and tocopheryl
linoleate.
X. Preservative
Other than water activity depressants and antimicrobial components, such as
triclosanTM, the compositions, according to the invention, may optionally
comprise one or
more preservatives such as polymethoxy bycyclic oxazolidine, methyl paraben,
propyl
paraben and DMDM hydantoin.
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CA 02584797 2007-04-26
xi. Viscosity Enhancer or Thickening Agent
The compositions, according to the invention, may optionally comprise a
viscosity
enhancer or thickening agent. Viscosity enhancers of various classes may be
chosen,
including microbial polysaccharides, such as xanthan gum; cellulose
derivatives, such as
methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose and
hydroxyethylcellulose; and sorbitol.
xii. Emulsifier
The compositions, according to the invention, may also comprise one or more
emulsifiers. Preferred emulsifiers under the invention include: polysorbate-
60Tm, sorbitol,
and sorbitan stearate. Such emulsifiers may be incorporated into the instant
compositions
singly or in any combination.
xiii. Vitamins, Proteins and Derivatives Thereof
The compositions, according to the invention, may also comprise one or more
ingredients which are vitamins, proteins or derivatives thereof, other than
those which may
be present in other components of the instant compositions. Vitamins, proteins
or
derivatives thereof may be incorporated into the compositions of the invention
either
singly or in any combination. Examples of vitamins, proteins or derivatives
thereof which
may be included in the compositions under the invention include: tocopheryl
acetate,
tocopheryl linoleate, panthenol, wheat oligosaccharides and hydrolyzed wheat
proteins.
xiv. Surfactant
The compositions, according to the invention, may optionally comprise one or
more surfactants. Surfactants used under the invention are preferably mild or
very mild
detergents. Preferred surfactants under the invention include: sodium laureth
sulfate and
cocamide DEA.
xv. Citric Acid
The compositions according to the invention may also comprise citric acid, a
naturally occurring compound present in both plant and animal cells as an
intermediate of
the Tricarboxylic acid cycle and in relatively high concentrations in citrus
fruit. It is
13
CA 02584797 2007-04-26
preferred that only plant and no animal byproducts are used. Under the
invention, citric
acid is preferably present in a concentration of from 0-10% by weight, more
preferably
from 0-5% by weight, and most preferably from 0 to about 2% by weight. The
concentration of citric acid may be adjusted slightly to provide a suitable
pH.
xvi. Allantoin
The composition according to the invention may also comprise allantoin.
Allantoin
is a natural product which occurs in both plants and animals, plants being
preferable here.
Allantoin is considered to stimulate cell proliferation and promote healing of
the skin. The
allantoin component of the composition is preferably present in a
concentration of from
0-5% by weight, preferably 0.01-2% by weight.
xvii. Aloe vera components
The composition according to the invention also comprises a cosmetically and
physiologically acceptable preparation obtained from the Aloe vera plant.
Constituents of
this plant are reported to prevent infection, promote wound healing, and to
have antifungal
properties. The gel obtained from Aloe vera leaves are said to be useful for
dry skin
conditions. The Aloe vera gel has also been recommended for treating fungal
skin
infections. The Aloe vera component of the composition is preferably present
in a
concentration of from 0.1-10% by weight, more preferably from 0.2-5% by
weight, and
most preferable from 0.5-1.5% by weight.
xviii. Natural Scents
The composition according to the invention also comprises one or more natural
scents. Natural scents added to the skin care compositions under the invention
impart a
pleasant, mild scent, and are formulated to avoid any negative impact on the
skin such as
drying, irritation or allergies. For example, natural scents may be obtained
from plant
materials in the form of essential oils by the process of fractional
distillation, thus avoiding
extraction procedures involving organic solvents.
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CA 02584797 2007-04-26
ixx. Other Plant or Herbal Extracts
The compositions according to the invention also comprise one or more natural
plant or herbal extracts, including matricaria extract, comfrey extract, and
cucumber
extract. Under the invention, natural plant extracts are preferably present in
a
concentration of from 0-5% by weight, more preferably from 0-2% by weight,
more
preferably from 0 to about 0.8% by weight.
Medicinal use of the herb known as comfrey dates back at least to the time of
the
Ancient Egyptian civilization, and it has been widely used as a herbal remedy
for hundreds
if not thousands of years (see, for example, P. Ody (1993) The Complete
Medicinal
Herbal, Dorling Kindersley, London, New York, Stuttgart). Nicholas Culpeper,
an
Elizabethan herbalist listed comfrey as being amongst the most effective
natural healing
agents. The English physician Charles J. Macalister, M.D. used comfrey
topically to treat
serious skin lesions - with remarkable results (C.J. Macalister (1936)
Narrative of an
Investigation Concerning an Ancient Medicinal Remedy and its Modern Utilities,
Republished 1955, The Lee Foundation for Nutritional Research, Milwaukee, WI).
One
constituent of comfrey considered to be responsible for its medicinal
properties is
allantoin.
Matricaria is another herb that has been used medicinally since antiquity.
Among
the skin conditions for which Matricaria has been recommended are: various
sores and
wounds, eczema and inflammation.
Without being limited by any theory of mode of action of any of these
constituents,
it is believed that topical use of the instant skin care compositions not only
helps to
maintain treated skin in a healthy condition, but also promotes healing of
dry, cracked,
sore, or damaged skin.
xx. pH
In the case of the skin cleanser composition, the preferred pH is in the range
of 6.0
to 8.0, more preferably the pH is in the range of 6.5 to 7.5.
The preferred pH of the skin moisturizer composition is in the range of 5.0 to
8.0,
more preferably the pH is in the range of 6.0 to 7Ø
In one embodiment, the composition of a skin moisturizer under the invention
comprises for example, a humectant, an emollient, a carrier or micro-carrier,
an
CA 02584797 2007-04-26
antimicrobial agent, an antimicrobial function enhancer, an unbound/excess
lipid remover,
a vitamin, protein or derivative thereof, plant extract, natural scents, and
water.
In a preferred embodiment, the composition of a skin moisturizer under the
invention comprises, for example, the following:
a humectant, such as glycerin;
a carrier or micro-carrier, such as hyaluronic acid or ceramic hydroxyapatite,
an
antimicrobial function enhancer, such as ceramic hydroxyapatite, an
unbound/excess lipid
remover, such as ceramic hydroxyapatite;
an emollient, such as glyceryl stearate, allantoin, or
nonoxynol-9;
an antimicrobial agent, such as Triclosan;
an anti-inflammatory agent, such as Aloe vera extract, or panthenol;
an emulsifier, such as polysorbate 60;
a preservative, such as DMDM hydantoin;
a sun block agent, such as octyl palmitate;
a vitamin or derivative thereof, such as tocopheryl acetate or wheat
oligosaccharides;
a protein or derivative thereof, such as hydrolyzed wheat proteins;
a plant extract, such as comfrey extract, or Matricaria extract;
a natural scent, such as oil of citrus fruit;
and water.
Methods, under the invention, for preparing a skin moisturizer composition
comprise the steps of formulating the constituents of each composition as four
separate
Phases, and subsequently combining each Phase.
The skin moisturizer composition may be formulated according to the following
Example.
EXAMPLE 1
Formulation of Skin Moisturizer Composition
a) Phase IM
A suitable volume of deionized water at ambient temperature was metered into a
first stainless steel vessel or tank, and the mixer was turned on. Ingredients
of Phase 1 M,
comprising nonoxynol-9, Aloe vera extract and panthenol were then added, and
the
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mixture was slowly heated to a predetermined temperature. Preferably Phase 1M
of the
composition is heated to a predetermined temperature in the range of 30 to 95
C, more
preferably in the range of 40 to 90 C, and most preferably in the range of 50
to 80 C. In a
preferred embodiment, methyl paraben is added after heating has begun, when
the
temperature of Phase 1M is in the range of 30 to 95 C, more preferably when
the
temperature of Phase 1M is in the range of 40 to 90 C, and most preferably
when the
temperature of Phase 1M is in the range of 50 to 80 C.
b) Phase 2M
The ingredients of Phase 2M, comprising glycerin and ceramic hydroxyapatite,
were combined in a suitable second vessel and mixed thoroughly until
completely
homogeneous. Phase 2M was added to the first vessel when the predetermined
temperature for Phase 1M had been attained.
c) Phase 3M
The constituents of Phase 3M, comprising stearic acid, octyl palmitate,
tocopheryl
acetate, safflower oil, and hydrogenated vegetable oil, were combined in a
stainless steel
third vessel, and the mixture was heated towards a predetermined temperature.
Preferably
the predetermined temperature for Phase 3M is in the range of 30 to 95 C, more
preferably
in the range of 40 to 90 C, and most preferably in the range of 50 to 80 C.
When most of the solid constituents had melted the mixer for the third vessel
was
turned on. When the temperature of the contents of both the third and first
vessels attained
their respective predetermined temperatures, Phase 3M was added to the first
or main
vessel, and the contents were mixed well.
After thorough mixing, heating was discontinued and the contents of the first
vessel were allowed to cool.
d) Phase 4M
The ingredients of Phase 4M, comprising tocopherol linoleate, matricaria
extract
and comfrey extract, were combined in a suitable fourth vessel, and heated to
a
predetermined temperature. Preferably the predetermined temperature for Phase
4M is in
the range of 30 to 60 C, more preferably in the range of 35 to 55 C, and most
preferably
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in the range of 40 to 55 C. When the temperature of the contents of the first
vessel were at
the same or a similar temperature as the predetermined temperature for Phase
4, the
ingredients of Phase 4 were transferred from the fourth vessel to the first
vessel with
thorough mixing. Heating was discontinued and the mixture was allowed to cool.
When the mixture was at a suitable temperature, preferably in the range of
20-40 C, more preferably in the range of 25-35 C, natural scent was added,
and the
mixture was thoroughly stirred until homogeneous.
The skin moisturizer composition of the current invention provides a smooth
moisturizer, which is white or slightly off-white in color, and has a delicate
scent of citrus
fruit. At a temperature of 25 C, it has a pH in the range of 6-7, a viscosity
in the range of
3500-6500 and preferably 4,400-5,100 centipoise, and a specific gravity near
1Ø
In one embodiment, the composition of a skin cleanser under the invention
comprises, for example, an antimicrobial agent, a viscosity enhancer, a
carrier or micro-
carrier, an antimicrobial function enhancer, and an unbound/excess lipid
remover, a
vitamin, protein or derivative thereof, plant extract, natural scent, and
water.
In a preferred embodiment, the composition of a skin cleanser under the
invention
comprises, for example, the following:
an antimicrobial agent, such as Triclosan;
an antimicrobial function enhancer, such as ceramic hydroxyapatite, and an
unbound/excess lipid remover, such as ceramic hydroxyapatite;
an emollient, such as propylene glycol, nonoxynol-9;
an anti-inflammatory agent, such as Aloe vera extract, panthenol;
a surfactant, such as cocamide DEA, sodium laureth sulfate;
an emulsifier, such as polysorbate 60, sorbitan stearate;
a preservative, such as propyl paraben, methyl paraben;
a sun block agent, such as octyl palmitate;
a vitamin or derivative thereof, such as tocopheryl linoleate or wheat
oligosaccharides;
a protein or derivative thereof, such as hydrolyzed wheat protein;
a plant extract, such as comfrey extract, or matricaria extract;
a natural scent, such as oil of cucumber;
and water.
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Methods, under the invention, for preparing the skin cleanser composition
comprise the steps of formulating the constituents of each composition as four
Phases, and
subsequently combining each Phase sequentially.
The skin cleanser composition may be formulated according to the following
Example.
EXAMPLE 2
Formulation of Skin Cleanser Composition
a) Phase 1 C
A suitable volume of deionized water at ambient temperature was metered into a
first stainless steel vessel or tank, and the mixer was turned on. Ingredients
of Phase 1 C,
comprising sodium laureth sulfate, Aloe vera extract, citric acid and
panthenol were then
added, and the mixture was thoroughly stirred.
b) Phase 2C
The ingredients of Phase 2, comprising sorbitol and ceramic hydroxyapatite,
were
combined in a suitable second vessel and mixed thoroughly until completely
homogeneous. Phase 2 was added to the first vessel.
c) Phase 3C
The constituents of Phase 3C, comprising propylene glycol, Polymethoxy
Bycyclic
Oxazolidine and Triclosan, were combined in a suitably sized third vessel, and
the
contents were thoroughly mixed. Mixing was continued and the mixture was
heated until
the mixture was homogeneous and it attained a predetermined temperature.
Preferably the
predetermined temperature for Phase 3 C is in the range of 35 to 95 C, more
preferably in
the range of 45 to 85 C, and most preferably in the range of 55 to 75 C.
Heating was
discontinued and the mixture was allowed to cool. When the temperature of
Phase 3C in
the third vessel was in the range of 15 to 35 C, and preferably in the range
of 18 to 25 C,
Phase 3C was transferred to the first vessel, and the contents were mixed
well.
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d) Phase 4C
Mixing of the contents of the first vessel was continued while the ingredients
of
Phase 4C at ambient temperature, comprising nonoxynol-9, cocamide DEA, comfrey
extract, and matricaria extract, were added sequentially to the first vessel.
Finally, natural scent was added to the mixture in the first vessel, and the
mixture
was thoroughly stirred until homogeneous.
The skin cleanser composition of the current invention provides a smooth,
viscous
liquid which is clear to slightly opaque, and has a slight scent of cucumber.
At a
temperature of 25 C, it has a pH in the range of 6.5-7.5, a viscosity in the
range of
3,000-4,000, even more preferably in the range of 3200-3800 centipoise, and a
specific
gravity near approximately 1Ø
A preferred embodiment of the skin moisturizer composition according to the
invention comprises the constituents shown in the following Example.
EXAMPLE 3
Skin Moisturizer Composition
Phase 1 comprises:
Deionized water, to 100% w/w;
Panthenol, up to 10% w/w;
Methyl paraben, up to 5% w/w; and
Aloe vera extract, up to 7% w/w.
Phase 2 comprises:
Glycerin, up to 10% w/w; and
Ceramic hydroxyapatite, up to 5% w/w.
Phase 3 comprises:
Stearic acid, up to 10% w/w;
Tocopherol acetate, up to 5% w/w;
Octyl palmitate, up to 10% w/w;
Safflower oil, up to 10% w/w;
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Hydrogenated vegetable oil, up to 10% w/w;
Propyl paraben, up to 5% w/w; and
Triclosan, up to 1% w/w.
Phase 4 comprises:
Plant extract - for example, extract of comfrey, matricaria, up to 5% w/w;
Tocopheryl lineate, up to 5% w/w;
Allantoin, up to 5% w/w; and
Oligosaccharides and hydrolyzed wheat protein.
A further constituent of a preferred embodiment of the skin moisturizer
composition is natural oil of citrus in the range of 0.01-0.1% w/w.
A preferred embodiment of the skin cleanser composition according to the
invention comprises the constituents shown in the following Example.
EXAMPLE 4
Skin Cleanser Composition
Phase 1 comprises:
Deionized water, to 100% w/w;
Panthenol, up to 10% w/w;
Aloe vera extract, up to 7% w/w; and
Citric acid, up to 10% w/w.
Phase 2 comprises:
Sorbitol, up to 10% w/w; and
Ceramic hydroxyapatite, up to 5% w/w.
Phase 3 comprises:
Methyl paraben, up to 5% w/w;
Propyl paraben, up to 5% w/w;
Propylene glycol, up to 10% w/w;
Disodium ethylenediaminetetraacetic acid, up to 2% w/w; and
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Triclosan, up to 1% w/w.
Phase 4 comprises:
Plant extract - for example, extract of comfrey, Matricaria up to 5% w/w;
Nonoxynol-9;
Hydroxypropyl methycellulose; and
Wheat oligossacharides and hydrolyzed wheat protein.
A further constituent of a preferred embodiment of the skin cleanser
composition is
natural oil of cucumber in the range of 0.01-0.1% w/w.
The present invention having been described in various embodiments, it will be
apparent to one of ordinary skill that many modifications can be made thereto
which
nevertheless utilize the methods and compositions of the invention as
disclosed. The scope
of the invention is defined by the appended claims rather than by the
embodiments
presented above.
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