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Title: Film-forming
compositions for protecting skin from body fluids and articles made
therefrom
United States Patent: 7,449,613
Issued: November 11, 2008
Inventors: Klofta; Thomas
James (Cincinnati, OH), Staudigel; James Anthony (Cincinnati, OH), Deckner;
George Endel (Cincinnati, OH)
Assignee: The Procter &
Gamble Company (Cincinnati, OH)
Appl. No.:
11/273,355
Filed: November 14, 2005
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Patheon
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Abstract
The present invention relates to a
film-forming barrier composition useful for protecting the skin from body
fluids, such as urine, feces, menses. The composition comprises a skin
conditioning agent, a viscosity enhancing agent and an oleophilic
film-forming agent. Optionally, the lotion may comprise skin care
ingredients for treating or maintaining skin health. The composition may
be applied to the skin by suitable delivery vehicles, such as absorbent
articles or components thereof, sheet materials, pads, bandages, sponges,
foam pads, pumps, sprays, depending on the viscosity of the composition.
Description of the
Invention
SUMMARY OF THE INVENTION
The present invention relates to a substantially anhydrous, film-forming
composition that forms a protective barrier on the skin. Specifically, the
composition of the present invention comprises: a. from about 1% to about
90% a skin conditioning agent; b. from about 15% to about 50% a viscosity
enhancing agent; c. from about 1% to about 20% an oleophilic film-forming
agent; and d. optionally, from about 0.01% to about 15% of a skin care
ingredient.
The composition may be applied to the skin by suitable delivery vehicles,
such as absorbent articles or components thereof, sheet materials, wipes,
pads, bandages, sponges, foam pads, pumps, sprays, and combinations thereof.
DETAILED DESCRIPTION OF THE INVENTION
The Film-Forming Composition
The composition of the present invention comprises a skin conditioning
agent, a viscosity enhancing agent and an oleophilic film-forming agent.
Optionally, the composition may comprise skin care ingredients for treating
or maintaining skin health. When the composition is applied to the skin, a
relatively uniform film is formed on the skin surface. The barrier nature of
the present composition protects the skin from direct contact with body
exudates, including liquids or irritants therein. The film forming nature of
the present composition provides good affinity to the skin such that the
composition is resistant to wash-off or rub-off. Additionally, the film
formed on the skin surface holds the skin care ingredients in intimate
contact. Thus, the present composition provides an efficient and extended
delivery of the relatively expensive skin care ingredients to the skin.
Further, the compositions used in the present invention are preferably
substantially anhydrous, especially if the delivery vehicle is an absorbent
article. As used herein, the term "substantially anhydrous" means the
composition typically has a water content of less than about 10%, preferably
less than about 5%, more preferably less than about 1%, and most preferably
less than about 0.5% by weight. The substantially anhydrous nature of the
compositions avoid the overhydration problem of the already susceptible skin
that has been or is exposed to a high relative humidity micro-environment.
Furthermore, such compositions minimize the potential wicking effect of the
highly absorbent core, which preferentially draws compositions containing
ample water towards the core, thus, reduces the amount of compositions
available for transfer to the skin. If drawn into the core, the oleaginous
composition of the present invention may interfere with the absorbency of
the core.
In a preferred embodiment, the composition is applied to the skin using an
absorbent article as the delivery vehicle. Suitable compositions for such
delivery vehicles should have a melting/rheological profile that meets
certain requirements. The compositions should preferably be solid or
semi-solid at room temperature (i.e., about 20.degree. C.) so that
"migration" on the substrate surface and the adverse effects to the
absorbency of the article are minimized. The compositions should also be at
least partially transferable to the skin by contact, normal wear motions
and/or body heat; therefore, the compositions are preferably plastic or
fluid at skin temperature (i.e., about 34-36.degree. C.) to facilitate the
transfer to the skin. Further, the compositions should have storage
stability under "stressful" storage conditions, such as storage temperatures
of at least about 45.degree. C. Since the compositions are substantially
immobilized and stable in storage, special barrier or wrapping materials may
be unnecessary in packaging the treated absorbent articles useful in the
present invention.
The term "semisolid", as used herein, means that the composition has a
rheology typical of pseudoplastic or plastic liquids. When no shear is
applied, the compositions can have the appearance of a semi-solid but can be
made to flow as the shear rate is increased. Without intending to be bound
by theory, it is believed that while such compositions contain primarily
solid components, they also include some liquid components.
To enhance the immobility of the preferred compositions, the viscosity of
the formulated compositions should be as high as necessary to prevent
substantial flow within the article to undesired locations. Specifically,
the compositions of the present invention have a zero shear viscosity at
room temperature between about 1.0.times.10.sup.6 centipoise and about
1.0.times.10.sup.8 centipoise. More preferably, the zero shear viscosity is
between about 5.0.times.10.sup.6 centipoise and about 5.0.times.10.sup.7
centipoise.
On the other hand, too high a viscosity may inhibit transfer of the
composition to the skin. Therefore, a balance should be achieved so the
viscosities are high enough to keep the compositions localized on the
surface of the article, but not so high as to impede transfer to the skin.
In addition, the compositions preferably have a final melting point above
skin temperature, more preferably above potential "stressful" storage
conditions that can be greater than 45.degree. C. (e.g., warehouse in
Arizona, car trunk in Florida, etc.). Therefore, the preferred compositions
will have the following melt profile
-- see Original Patent.
A. Skin Conditioning Agents
As used herein, the term "skin conditioning agent" means a material that
protects against wetness or irritation, softens, soothes, supples, coats,
lubricates, reduces flaking, moisturizes, protects and/or cleanses the skin.
Skin conditioning agents may maintain the normal, healthy skin condition.
One type of skin conditioning agents, generally referred to as emollients,
are particularly useful in improving the dry skin condition by restoring its
moisture level as well as its softness, smoothness, pliability, and
flexibility. Another type of skin conditioning agents, generally referred to
as moisturizers or humectants, attract moisture from the surrounding
atmosphere and enhance the water absorption of the stratum corneum (i.e.,
the outer, corny layer of the skin). Another type of skin conditioning
agents, generally referred to as barrier protectants, which form an
occlusive (i.e., non-water-permeable) layer on the skin surface that
prevents or retards moisture losses from the deeper layers of the skin to
the atmosphere. The occlusive agents also provide barrier protection to the
skin against larger molecules, such as fecal matter, urine, enzymes, and
other irritants.
The amount of skin conditioning agent included in the composition will
depend on a variety of factors, including the particular skin conditioning
agent involved, the skin benefits desired, the other components in the
composition, and like factors. The skin conditioning agents will generally
comprise from about 1 to about 90 wt % of the composition. Preferably, the
skin conditioning agents comprise from about 10 to about 85 wt %, more
preferably from about 20 to about 80 wt %, and most preferably from about 30
to about 75 wt %, of the composition.
Exemplary skin conditioning agents useful in the present invention include,
but are not limited to, petroleum-based emollients; fatty acid esters;
polysiloxanes; polyol polyesters; esters or ethers of polyhydroxy alcohols;
fatty alcohol esters of polyprotonic acids; animal oils, fats, and their
derivatives; vegetable oils, hydrogenated vegetable oils, and their
derivatives; branched hydrocarbons; fatty alcohol ethers; free sterols,
sterol esters and their derivatives; sphingolipids; phospholipids; and
mixtures thereof.
Suitable petroleum-based emollient include petrolatums, i.e., hydrocarbons
or mixtures of hydrocarbons; particularly preferred are hydrocarbons having
chain lengths of from C10 to C100. Petroleum-based emollients within this
chain length range include mineral oil and petrolatum. Mineral oil usually
refers to less viscous mixtures of hydrocarbons having from 10 to 30 carbon
atoms, though the hydrocarbon molecular weight distribution may vary. Since
the lower molecular weight hydrocarbons can cause irritation in some
individuals, mineral oils having a small percentage of lower molecular
weight hydrocarbons are preferred. Petrolatum usually refers to more viscous
mixtures of hydrocarbons of higher molecular weight hydrocarbons. Petrolatum
and mineral oil are preferred skin conditioning agents for compositions of
the present invention due to their ability to protect the skin from harmful
or irritating stimuli. Petrolatum is particularly preferred because of its
good barrier properties. When employed, petrolatum comprises at least about
15 wt %, preferably at least about 25 wt %, more preferably at least about
50 wt % of the composition.
Suitable fatty acid ester type skin conditioning agents include those
derived from C.sub.12-C.sub.50 fatty acids, preferably C.sub.16-C.sub.22
saturated fatty acids, and short chain (C.sub.1-C.sub.8, preferably
C.sub.1-C.sub.3) monohydric alcohols. Representative examples of such esters
include methyl palmitate, methyl stearate, isopropyl laurate, isopropyl
myristate, isopropyl palmitate, ethylhexyl palmitate and mixtures thereof.
Suitable fatty acid ester skin conditioning agents can also be derived from
esters of long chain fatty alcohols (C.sub.12-C.sub.50, preferably
C.sub.12-C.sub.22) and short chain acids (e.g., lactic acid), such as lauryl
lactate and cetyl lactate. Also suitable for use herein are fatty acid
esters having branched and/or unsaturated alkyl chains in their acid or
alcohol moieties. Nonlimiting examples include diisopropyl adipate
(available as CERAPHYL.RTM. 230 from International Specialty Products,
Wayne, N.J.), octyldodecyl stearoyl stearate, isononyl isononanoate
(available as SALACOS.RTM. 99 from Ikeda Corp., Island Park, N.Y.),
isostearyl isononanoate, octyl palmitate, octyl hydroxystearate, stearyl
heptanoate, ceterayl octanoate, butyl octanol, 2-ethylhexyl-12-hydroxy
stearate, decyl oleate, dioctyl adipate, dioctyl succinate, isocetyl
stearate, octyl cocoate, octyl palmitate, and mixtures thereof. Other
suitable fatty acid esters include laurel laureate, stearyl palmitate and
stearyl behenate (available as PURESTER.RTM. 24, 34, and 40 from Strahl &
Pitsch, West Babylon, N.Y.). Suitable fatty acid esters also include certain
branched esters, such as cetearyl octanoate (CRODAMOL.RTM. CAP), lignoceryl
erucate (CRODAMOL.RTM. LGE), and pentaerythrityl tetracaprylate/tetracaprate
(CRODAMOL.RTM. PTC); all are available from Croda Inc., Parsippany, N.J.
Other suitable skin conditioning agents are polyol polyesters, including the
"liquid" polyol polyesters which have a complete melting temperature at or
below body temperature (i.e., about 37.degree. C.) and the "solid" polyol
polyesters which are solid or semi-solid at or above body temperature. As
used herein, the term "polyol" means a polyhydric alcohol containing at
least 2, preferably from 4 to 12, and most preferably from 6 to 8 hydroxy
groups. Polyols include mono- di- and tri-saccharides, sugars, sugar
alcohols, other sugar derivatives (e.g., alkyl glucosides), pentacrythritol
and polyvinyl alcohol. Exemplary polyols include, but are not limited to,
polyhydric alcohols such as pentaerythritol; sugars such as raffinose,
maltodextrose, galactose, sucrose, glucose, xylose, fructose, maltose,
lactose, mannose and erythrose; and sugar alcohols such as erythritol,
xylitol, malitol, mannitol and sorbitol. Such polyols are esterified with
fatty acids and/or other organic radicals having at least 2 carbon atoms and
up to 30 carbon atoms. While it is not necessary that all of the hydroxyl
groups of the polyol be esterified, the preferred polyol polyesters have
substantially all (e.g., at least about 85%) of the hydroxyl groups
esterified. Particularly preferred are sucrose polyol polyesters such as
sucrose polycottonate, sucrose polysoyate, and sucrose polybehenate.
Mixtures of such polyol polyesters are also suitable skin conditioning
agents for the present invention. Other suitable polyol polyesters and
mixtures thereof are disclosed in U.S. Pat. No. 5,609,587, issued to Roe on
Mar. 11, 1997, and in U.S. Pat. No. 5,607,760, issued to Roe on Mar. 4,
1997, the disclosure of each is incorporated herein by reference. Other
ester materials are further described in U.S. Pat. Nos. 2,831,854,
4,005,196, to Jandacek, issued Jan. 25, 1977; U.S. Pat. No. 4,005,195, to
Jandacek, issued Jan. 25, 1977, U.S. Pat. No. 5,306,516, to Letton et al.,
issued Apr. 26, 1994; U.S. Pat. No. 5,306,515, to Letton et al., issued Apr.
26, 1994; U.S. Pat. No. 5,305,514, to Letton et al., issued Apr. 26, 1994;
U.S. Pat. No. 4,797,300, to Jandacek et al., issued Jan. 10, 1989; U.S. Pat.
No. 3,963,699, to Rizzi et al, issued Jun. 15, 1976; U.S. Pat. No.
4,518,772, to Volpenhein, issued May 21, 1985; and U.S. Pat. No. 4,517,360,
to Volpenhein, issued May 21, 1985; all of which are incorporated by
reference herein.
Also useful herein are esters of polyhydroxy alcohols, which are generally
used as the humectant-type skin conditioning agents. This type of esters may
include glyceryl esters including glycerides and derivatized glycerides,
polyglyceryl esters, and glycolic esters. Glyceryl esters are derived from
glycerin, its derivatives and one or more carboxylic acid moieties.
Non-limiting examples include various C1-C30 mono-, di- or tri-esters of
glycerin and derivatives thereof, such as mono-, di-, tri-glycerides,
acetoglycerides, and ethoxylated glycerides. Exemplary glyceryl esters
include glyceryl behenate, glyceryl oleate, glyceryl stearate, glyceryl
palmitate, glyceryl distearate, glyceryl dipalmitate, and the like.
Polyglyceryl esters having C12-C22 acid moieties are also suitable for use
herein. Non-limiting examples include polyglyceryl-4 isostearate,
polyglyceryl-3 oleate, diglyceryl monooleate, tetraglyceryl monooleate and
the like. Glycolic esters are derived from C2-C6 glycols, including ethylene
glycol, propylene glycol, butylene glycol, hexylene glycol and derivatives
thereof, and one or more carboxylic acid moieties having C1-C30 chains.
Specific examples of glycolic esters include polyethylene glycols (PEGs),
such as PEG-2, PEG-3, PEG-30 and PEG-50, and polypropylene glycols (PPGs),
such as PPG-9, PPG-12, PPG-15, PPG-17, PPG-20, PPG-26, PPG-30 and PPG-34.
Also useful herein are fatty alcohol esters of polyprotonic acids, including
mon-, di- or tri-esters derived from C8-C30 fatty alcohols and citric acid,
malic acid, adipic acid, sebacic acid and the like.
Ethers of polyhydroxy alcohols, such as dialkyl ethers having C12-C30 alkyl
chains or alkyl ethers having one C12-C30 alkyl chain and a lower (C1-C8)
alkyl chain, are also suitable skin conditioning agents for the present
invention. Glycolic ethers, such as C4-C20 alkyether of PEG or PPG,
di-C8-C30 alkyl ethers of PEG or PPG, are also suitable for use herein.
Also useful herein as skin conditioning agents are sphingolipids, such as
ceramides, sphingosines, phytosphingosines, and the like; and phospholipids,
such as lecithin, cephalin, phosphatidylserine, phosphatidylinositol,
phosphatidic acid, sphingomyelin, and the like; and mixtures thereof.
Another effective skin conditioning agent having superior barrier properties
is a mixture of components which simulate the skin's water-barrier forming
lipid complex, particularly vernix (i.e., the substance covering the bodies
of fetuses or newborns of human or other mammals). A preferred skin
conditioning agent is a simulated vernix, which comprises a mixture of
sterols, sterol esters and triglycerides. Other substances occurring
naturally in the stratum corneum are also preferred, such as sodium
pyrrolidone carboxylic acid, sodium lactate/lactic acid, L-proline,
guanidine, pyrrolidone, ceramide, and urea. Other skin conditioning agents
derived from natural sources are also suitable for use herein, such as
hydrolyzed protein and other collagen-derived proteins, keratin and
derivatives, acetamide MEA, and the like.
Vegetable oils and hydrogenated vegetable oils are also useful herein.
Non-limiting examples include safflower oil, castor oil, coconut oil,
cottonseed oil, menhaden oil, palm kernel oil, palm oil, peanut oil, soybean
oil, rapeseed oil, linseed oil, rice bran oil, pine oil, sesame oil,
sunflower seed oil, jojoba oil, tea tree oil, avocado oil, olive oil, canola
oil, their hydrogenated products such as cocoa butter, shea butter, and
mixtures thereof. Some of the fully or partially hydrogenated vegetable oils
may be solid or semi-solid (i.e., having a waxy consistency) at ambient
temperature such that they are also suitable for use herein as viscosity
enhancing agents.
Also useful herein are animal fats and oils such as shark liver oil, cod
liver oil, lanolin, their derivatives, and mixtures thereof. In some
embodiments, the skin conditioning agent comprises petrolatum and a mixture
of lanolin and lanolin derivatives in a ratio ranging from about 1:2 to
about 1:5.
Nonlimiting examples of sterols suitable for use herein include cholesterol,
ergosterol, sitosterol, cholecalciferol, and other sterols found in
phytosterols, soy sterols or tall oil sterols; lanosterols and other sterols
found in lanolin and hydrogenated lanolin; and derivatives thereof, such as
acetylated lanolin (e.g., ACYLAN.RTM. from Croda Inc., Parsippany, N.J.).
Nonlimiting examples of sterol esters suitable for use herein include
stearate, palmitate, acetate, lanolate, macadamiate, nonanoate, oleate,
butyrate, hydroxystearate, isostearate, sulfate, isostearate carbonate of
cholesterol and other sterols. A particularly preferred sterol esters is a
mixture of C10-C30 carboxylic acid esters of sterols, which is predominantly
a cholesterol/lanosterol mixture (e.g., Super Sterol Ester.RTM. from Croda,
Inc., Parsippany, N.J.). Super Sterol Ester.RTM. is derived from wool wax by
a process disclosed in part in U.S. Pat. No. 4,138,416 issued to Koresawa et
al., which is incorporated herein by reference. Other nonlimiting examples
of sterol esters suitable for use herein include stearate, palmitate,
acetate, lanolate, macadamiate, nonanoate, oleate, butyrate, hydroxystearate,
isostearate, sulfate, isostearate carbonate of cholesterol and other
sterols.
Also useful herein as skin conditioning agents are C7-C40 branched
hydrocarbons, such as ISOPAR.RTM. isoparaffins (available from Exxon
Chemical Company, Houston, Tex.) and PERMETHYL.RTM. (available from
Presperse Inc., Piscataway, N.J.). Squalane, squalene, and the like are also
suitable skin conditioning agents. Squalene, being the partially unsaturated
form of squalane, is oxidatively unstable and may require incorporation of
anti-oxidants.
Suitable skin conditioning agents also include polysiloxanes having
monomeric siloxane units of the following structure
-- see Original Patent.
In some embodiments, the skin conditioning agent may be a substituted
polymethylsiloxane wherein at lease one substituent is a functional group
selected form the group consisting of methyl, phenyl, amino, other alkyl,
carboxyl, hydroxyl, ether, polyether, aldehyde, ketone, amide, ester, thiol,
and mixtures thereof. Particularly preferred for use herein is
polydimethylsiloxane.
Viscosity of polysiloxanes useful for the present invention may vary as
widely as the viscosity of polysiloxanes in general vary, so long as the
polysiloxane is flowable or can be made to be flowable for application to
the absorbent article. This includes, but is not limited to, viscosity as
low as 5 centistokes (at 37.degree. C. as measured by a glass viscometer) to
about 20,000,000 centistokes. Preferably the polysiloxanes have a viscosity
at 37.degree. C. ranging from about 5 to about 5,000 centistokes, more
preferably from about 5 to about 2,000 centistokes, most preferably from
about 100 to about 1000 centistokes. High viscosity polysiloxanes which
themselves are resistant to flowing can be effectively deposited upon the
absorbent articles by such methods as, for example, emulsifying the
polysiloxane in surfactant or providing the polysiloxane in solution with
the aid of a solvent, such as hexane, listed for exemplary purposes only.
Particularly suitable for use herein are polysiloxane compounds having long
(C12-C60, preferably C30-C50) linear alkyl groups or phenyl groups,
including phenyl-functional polymethylsiloxane compounds (e.g.,
polyphenylmethyl siloxane available as Dow Corning 556 Fluid) and cetyl or
stearyl functionalized dimethicones such as Dow 2502 and Dow 2503
polysiloxanes, respectively. In addition to such substitution with
phenyl-functional or alkyl groups, effective substitution may be made with
amino, carboxyl, hydroxyl, ether, polyether, aldehyde, ketone, amide, ester,
and thiol groups. Of these effective substituent groups, the family of
groups comprising phenyl, amino, alkyl, carboxyl, and hydroxyl groups are
more preferred than the others; and phenyl-functional groups are most
preferred.
Other alkyl polysiloxanes include SF 1318, SF 1642 and SF 1632 (available
from General Electric, Corp., Waterford, N.Y.), trimethyl siloxysilicates
such as WACKER-BELSIL.RTM. TSM 803 MQ (available from Wacker Silicones,
Adrian, Mich.) and MIRASIL.RTM. DPDM (available from Rhone-Poulenc,
Cranbury, N.J.) are used in some embodiments. Other preferred polysiloxane
compounds for use in the present invention are disclosed in U.S. Pat. No.
5,059,282 (Ampulski et al), issued Oct. 22, 1991, which is incorporated
herein by reference.
B. Viscosity Enhancing Agents
The compositions of the present invention contain viscosity enhancing agents
that thickens, gels, or hardens the composition such that the composition is
immobilized or locked at the location (e.g., on the surface or inside the
cavity of the delivery vehicle) it is applied. When an absorbent article is
used as the delivery vehicle, the viscosity enhancing agent is especially
useful in minimizing the migration and loss of the film-forming compositions
which, without the viscosity enhancing agents, would have a plastic or fluid
consistency at ambient temperature.
The amount of the viscosity enhancing agent in the composition will depend
on a variety of factors, including the skin conditioning agents used,
especially their viscosity at room temperature and at skin temperature, and
their melting points, characteristics of other components in the composition
(e.g., skin care ingredients), and like factors. When present, the
composition typically comprises from about 15 to about 50 wt % of the
viscosity enhancing agent. Preferably, the composition comprises from about
20 to about 45 wt %, most preferably from about 25 to about 40 wt %, of the
viscosity enhancing agent.
Exemplary viscosity enhancing agents include organic materials such as
natural or synthetic waxes, C12-C60 alcohols, C12-C60 acids, alpha-hydroxy
fatty acids, polyhydroxy fatty acid esters, polyhydroxy fatty acid amides,
and inorganic/organic materials such as metal ester complexes containing
zinc, calcium, aluminum or magnesium, fumed silicas, and organoclays. Other
suitable viscosity enhancing agents are disclosed in co-pending U.S. patent
application Ser. No. 09/563,638, filed by Gatto et al. on May 2, 2000, the
disclosure of which is hereby incorporated by reference. Some skin
conditioning agents, particularly polyol polyesters, glyceryl esters,
polyglyceryl esters and polysiloxanes may have a solid or semi-solid at
ambient temperature and are also suitable for use herein as viscosity
enhancing agents.
The organic viscosity enhancing agents are preferably miscible with (or
solubilized in) the skin conditioning agent. The organic viscosity enhancing
agents preferably have a melting point of at least about 35.degree. C.,
preferably at least about 40.degree. C., so that the viscosity enhancing
agents do not have a tendency to migrate or flow at ambient temperature.
Their high melting points and miscibility with the skin conditioning agents
help thickening and solidifying the composition and immobilize the
composition in or on the desired location of the delivery vehicle.
Typically, the organic viscosity enhancing agents have a melting point in
the range of from about 50.degree. C. to about 150.degree. C.
Suitable viscosity enhancing agents include C12-C60 alcohols, preferably
C16-C22 fatty alcohols, most preferably crystalline high melting materials
selected from the group consisting of cetyl alcohol, stearyl alcohol,
behenyl alcohol, and mixtures thereof. Behenyl alcohol is particularly
preferred. When employed, the C16-C22 fatty alcohols comprise from about 1
to about 90 wt %, preferably from about 5 to about 50 wt %, more preferably
from about 10 to about 30 wt %, of the total weight percent of the viscosity
enhancing agents.
Other suitable viscosity enhancing agents include C12-C60 acids, preferably
C16-C22 fatty acids, most preferably selected from the group consisting of
palmitic acid, stearic acid, behenic acid, oleic acid, linoleic acid,
myristic acid, ricinoleic acid, eurcic acid, lauric acid, isostearic acid,
and mixtures thereof. Mixtures of palmitic acid and stearic acid are
particularly preferred. The substantially linear structure and high melting
point of these viscosity enhancing agents speed up the solidification of the
composition and lock it to the location on the delivery vehicle where it is
deposited. Other suitable viscosity enhancing agents that may be used herein
are alpha-hydroxy fatty acids, including 12-hydroxystearic acid,
12-hydroxylauric acid, 16-hydroxyhexadecanoic acid, and mixtures thereof.
Nonlimiting examples of suitable fatty acids are further described in U.S.
Pat. No. 5,429,816, issued to Hofrichter et al. on Jul. 4, 1995, and U.S.
Pat. No. 5,552,136, issued to Motley on Sep. 3, 1996, disclosure of each is
incorporated by reference herein.
Waxes are also suitable for use herein as viscosity enhancing agents.
Natural waxes may include, but are not limited to, carnauba, ozokerite,
beeswax, candelilla, paraffin, ceresin, esparto, ouricuri, rezowax, and
other known mined and mineral waxes. Synthetic waxes may include, but are
not limited to, paraffin waxes and microcrystalline waxes. It is
particularly advantageous to use these waxes that form microcrystalline
structures upon cooling and/or solidifying. Without being bound by theory,
it is believed that the formation of microcrystallites may overcome the
tendency of the components (especially the immiscible or low molecular
weight, mobile components) to separate and "lock" or "freeze" the
composition into a substantially homogeneous mixture. Exemplary paraffin
waxes are available as SHELLWAX.RTM.100, 120, 200, 300, and 400 from Shell
Chemical Company, Houston, Tex. and as PARAFFIN.RTM. S.P. 434 from Strahl
and Pitsch Inc., West Babylon, N.Y. Exemplary microcrystalline waxes include
SHELLWAX.RTM.405 from Shell Chemical Company; 180-M, W-445, and W-835 from
CK-Witco, Greenwich, Conn.; ULTRAFLEX.RTM., BE SQUARE.RTM.175 and FORTEX.RTM.
from Petrolite, Piscataway, N.J.
Also suitable for use herein as viscosity enhancing agents are block
copolymers made from styrene and olefinin monomers. Particularly preferred
block copolymers for use herein are polystyrene-ethylene/butylene-polystyrene
block copolymers. Such linear block copolymers of styrene-ethylene/butylene-styrene
(S-EB-S) are commercially available under the trade designation KRATON.RTM.
G1600 series, particularly KRATON.RTM. G-1652, from Kraton Polymers,
Houston, Tex. Also preferred for use herein are
polystyrene-ethylene-ethylene/propylene-styrene (S-E-EP-S) block copolymers,
wherein the ethylene/propylene block is derived from selective hydrogenation
of the unsaturation sites within the polystyrene-isoprene/butadiene-styrene
block copolymers. Hydrogenated polystyrene-isoprene/butadiene-styrene (S-IB-S)
block copolymers are commercially available under the trade designation
SEPTON.RTM. 4000 series from Kuraray America, Inc. New York, N.Y.
Other suitable viscosity enhancing agents that may be used herein include
polyhydroxy fatty acid esters, polyhydroxy fatty acid amides, and mixtures
thereof. Preferred esters and amides will have three or more free hydroxy
groups on the polyhydroxy moiety and are typically nonionic in character.
Because of the possible skin sensitivity of those using articles to which
the composition is applied, these esters and amides should also be
relatively mild and non-irritating to the skin. Suitable polyhydroxy fatty
acid esters, polyhydroxy fatty acid amides are disclosed in U.S. Pat. No.
5,643,588, issued to Roe et al. on Jul. 1, 1997, the disclosure of which is
hereby incorporated by reference.
The inorganic/organic viscosity enhancing agents generally are particulates
in the present composition. In addition to thickening, solidifying and
immobilizing the composition, these particulate materials are also useful in
suspending immiscible components, such as skin care ingredients or other
additives, in the composition. For example, hydrophilic or water-soluble
skin care ingredients may be substantially uniformly dispersed in the
oleaginous compositions. The resulting uniform dispersion improves the
processability of the composition, and provides a more uniform application
of the skin care ingredients in or on the delivery vehicle.
Suitable viscosity enhancing agents include treated and untreated fumed
silicas. Fumed silicas are particles that do not dissolve in the oleaginous
compositions. Rather, the viscosity of the oleaginous composition is raised
by a hydrogen bonded network of fumed silica particles. Exemplary untreated
fumed silicas are available from Cabot Corp., Tuscola, Ill. under the trade
designations M5 and MS-55. Exemplary surface-treated fumed silicas are also
available from Cabot Corp., Tuscola, Ill. under the trade designations
TS-720 and TS-610.
Suitable viscosity enhancing agents also include organoclays such as
modified hectorite and smectite clays These hectorite and smectite clays are
modified with quaternary ammonium compounds to make the surface of the clay
particles hydrophobic while maintaining hydrophility on the edges of the
clay particle due to exposed hydroxyl groups. These organoclays are
insoluble particles dispersed in the oleaginous composition and form a
hydrogen-bonded network, which increases the viscosity of the composition.
Exemplary hectorite clays are available under the trade designations
BENTONE.RTM. 27, 38, and SD-3, and exemplary bentonite clays are available
under the trade designations BENTONE.RTM.34, 52 and SD-1 (all are available
from Rheox Hightstown, N.J.).
Other viscosity enhancing agents useful in the present invention include
metal ester complexes of aluminum, magnesium, or zinc with stearates,
benehates, palmitates or laureates.
C. Film-forming Agents
The compositions of the present invention also include film-forming agents.
By incorporating the film-forming agents, the compositions are more easily
spread over the skin to form a protective barrier coating. The film-forming
agents enhance the adherence of the composition to the skin and render the
composition resistance to wash-off or rub-off. Consequently, the skin care
ingredients in the composition stay on the skin longer. Film-forming agents
are preferably soluble or miscible with oleogenous components in the
composition to provide a substantially homogeneous mixture. Thus, suitable
film-forming agents are preferably oleophilic and water-resistant. The
composition of the present invention typically comprises from about 1 to
about 20 wt %, preferably from about 2 to about 15 wt %, more preferably
from about 5 to about 12 wt %, of the film-forming agent.
Also useful herein as film-forming agents are polyalkenes include
polyethylenes having a molecular weight ranging from about 300 to about 3000
(available as PERFORMALENE.RTM. from New Phase Technologies, Piscataway,
N.J.); polyisobutylenes (available as VISTANEX.RTM. from Exxon Chemical
Company, Houston, Tex.); polyisobutenes (available as PRESPERSE.RTM. from
Amoco, Chicago, Ill.); polydecenes (SILKFLO.RTM. TM-366NF and TM-364NF,
available from Amoco); and hydrogenated polyisobutenes (PANALANE.RTM. L-14E
and H-300E, available from Lipo Chemicals, Inc., Paterson, N.J.).
Another suitable oleophilic film-forming agents are copolymers of
vinylpyrrolidone (PVP) and long chain alpha olefins, including, but are not
limited to, PVP/eicosene copolymers (GANEX.RTM. V-220 and V-220F), and
tricontanyl PVP copolymers (GANEX.RTM. WP-660). All are available from
International Specialty Products, Wayne, N.J.
Also suitable for use herein as film-forming agents are GLOSSAMER.RTM.
L6600, available from International Lubricants Inc., Seattle, Wash. This
material is a liquid at room temperature. It is synthesized by the
copolymerization of purified vegetable oils from Brassica Campestris and
Aleurities Fordi sources.
Also suitable for use herein as film-forming agents are acrylic copolymers
having long (C8-C30) alkyl chains to enhance their oleophilicity, such as
acrylate/octylacrylamide copolymers (available as DERMACRYL.RTM. 79 and LT
from National Starch and Chemical, Bridgewater, N.J.). Other suitable
film-forming agents include, but are not limited to, polyethylene glycol
derivatives of Beeswax (ESTOL.RTM. E04BW-3752, E06BW-3753 and E03BW-3751,
available from Unichema, Wilmington, Del.); and fatty acid ester/fatty acid
anhydride grafted polyolefins wherein the esters and anhydrides are derived
from C12-C22 fatty acid moieties, for example, C30-C38 olefin/isopropyl
maleate/maleic anhydride copolymer (PERFORMA.RTM. V1608, available from New
Phase Technologies, Piscataway, N.J.).
D. Optional Other Components
The film forming compositions of the present invention may comprise other
components including, but are not limited to, water, surfactants, skin care
ingredients, anti-oxidants, pH buffering systems, disinfectants,
antibacterial agents, antiviral agents, pharmaceutical actives, perfumes,
pigments, deodorants, opacifiers, astringents, solvents, preservatives, and
the like. Most of these materials are well known in the art as additives for
such formulations and can be employed in appropriate amounts in the
compositions for use herein. Particular preferred surfactants and skin care
ingredients are disclosed in more details below.
Surfactants may be incorporated in the film forming composition of the
present invention to solubilize or compatiblize certain film-forming agents
or viscosity enhancing agents in the skin conditioning agents. Suitable
surfactants typically have hydrophilic lipophilic balance (HLB) values no
more than about 7. Particularly suitable surfactants are alkyl ethoxylates
such as C.sub.12-C.sub.22 fatty alcohol ethoxylates having an average degree
of ethoxylation of from about 2 to about 30. These and other suitable
surfactants are disclosed in U.S. Pat. No. 5,643,588, issued to Roe et al.
on Jul. 1, 1997, the disclosure of which is hereby incorporated by
reference.
Safe and effective skin care ingredients may be incorporated in the present
composition in the amount ranging from about 0.01 to about 15 wt %,
preferably from about 0.1 to about 10 wt %, and more preferably from about 1
to about 7 wt %. Such materials include Category I and Category III actives.
Category I and Category III actives are known to provide multiple skin
benefits, such as skin protection, itch prevention, irritation prevention,
via various mechanisms. It will be recognized that several of the Category I
and Category III actives listed below are "skin conditioning agents" as
defined herein. Category I actives include: allantoin, aluminum hydroxide
gel, calamine, cocoa butter, dimethicone, cod liver oil (in combination),
glycerine, kaolin, petrolatum, lanolin, mineral oil, shark liver oil, white
petrolatum, talc, topical starch, zinc acetate, zinc carbonate, zinc oxide,
and the like. Category III actives include: live yeast cell derivatives,
aldioxa, aluminum acetate, microporous cellulose, cholecalciferol, colloidal
oatmeal, cysteine hydrochloride, dexpanthenol, Peruvean balsam oil, protein
hydrolysates, racemic methionine, sodium bicarbonate, Vitamin A, and the
like.
Other skin care ingredients suitable for the film-forming compositions of
the present invention may include, but are not limited to, vitamins, pH
control agents or proton donating agents, protease inhibitors, enzyme
inhibitors, chelating agents, anti-microbials, skin soothing agents and the
like.
Suitable vitamins include A, B.sub.3, B.sub.5, niacinamide, panthenol, C and
derivatives, D.sub.3, E and derivatives, such as E acetate. Suitable skin
soothing agents include those materials derived from botanical extracts,
marine sources, mineral sources, and the like, such as aloe vera, chamomile,
calendula, comfrey, yarrow, witch hazel, sea weed, and oat extracts. Other
nonlimiting examples of the skin care ingredients are described in
co-pending U.S. application Ser. No. 09/041,509, by McOsker et al. filed on
Mar. 12, 1998; U.S. application Ser. No. 09/041,232, by Rourke et al filed
on Mar. 12, 1998; U.S. application Ser. No. 09/041,266, by Roe et al. and
U.S. application Ser. No. 09/041,196, by Underiner et al., both filed on
Mar. 12, 1998; Patent Application EP 97/120,699 and EP 97/120,700 both by
Palumbo et al. and filed on Nov. 26, 1997; U.S. Pat. No. 5,091,193 issued to
Enjolras et al, on Feb. 25, 1992; U.S. Pat. No. 4,556,560 issued to
Buckingham on Dec. 3, 1985; U.S. Pat. No. 5,376,655 issued to Imaki et al.
on Dec. 27, 1994; U.S. Pat. No. 5,091,193 issued to Enjolras et al. on Feb.
25, 1992; U.S. Pat. No. 3,935,862 issued to Kraskin on Feb. 3, 1976; U.S.
Pat. No. 5,409,903 issued to Polak et al. on Apr. 25, 1995; U.S. Pat. No.
4,556,560 issued to Buckingham on Dec. 3, 1985; all are incorporated by
reference herein.
Particularly preferred skin care ingredients herein include: zinc oxide,
talc, starch, allantoin, aloe vera, chamomile, vitamins, hexamidine and its
salts and derivatives, hexamidine diisethionate, and its salts, triacetin,
phytic acid, ethylenediamine tetraacetic acid (EDTA), phenylsulfonyl
fluorides such as 4-(2-aminoethyl)-benzenesulfonylfluoride hydrochloride,
chitosan, and mixtures thereof.
These skin care ingredients may comprise from 0.01 to 10 wt %, preferably
from about 0.1% to about 6 wt %, more preferably from about 0.1% to about 4
wt % of the composition.
Oxidation of unsaturations in substances, such as unsaturated hydrocarbons,
proteins, lecithin and their derivatives, may lead to rancidity of the
composition. Anti-oxidants can be added to minimize or prevent the oxidation
process, and enhance the shelf life of the composition. Anti-oxidants useful
herein should preferably be mild and non-irritating. Anti-oxidants from
natural sources are preferred, such as Vitamin E and derivatives, including
tocopherol, tocopherol acetate, mixed tocopherols (available as COVI-OX T-50
or T-70 from Henkel Corp, Ambler, Pa.), and the like. These anti-oxidants
are also useful as skin anti-oxidants, which minimizes the wrinkles and
dullness of the skin and provides a more youthful looking and firmer
textured skin.
A preservative will also be needed to prevent bacterial growth and odors
thereof, particularly in compositions having a relatively high water
content. Suitable preservatives include propyl paraben, methyl paraben,
benzyl alcohol, benzalkonium chloride, tribasic calcium phosphate, BHT, or
acids such as citric, tartaric, maleic, lactic, malic, benzoic, salicylic,
and the like.
Suitable solvents include propylene glycol, glycerine, cyclomethicone, C2-C6
glycols (particularly, ethylene glycol, propylene glycol and hexylene
glycol), diol and multi-hydroxy based solvents.
III. Delivery Vehicles
The composition of the present invention may be applied to the skin by hand
or by delivery vehicles. Exemplary delivery vehicles include web materials
or substrates such as tissues, wipes, sponges, cotton balls, pads, non-woven
webs, patches, bandages, paper, fabrics, and the like. The delivery vehicles
may also be canisters, sticks, or stick casings, aerosol dispensers, roller
dispensers, pump sprays, trigger sprays, and the like. Any combination of
the above is also suitable for use herein as a delivery vehicle. Nonlimiting
examples of some delivery vehicles are described in co-pending U.S. patent
application Ser. No. 09/326,149, filed by McOsker et al. on Jun. 4, 1999,
U.S. patent application Ser. No. 09/370,396, filed by McOsker et al. on Aug.
6, 1999, and U.S. Pat. No. 5,000,356, issued to Johnson et al. on Mar. 19,
1991; all are incorporated herein by reference.
In one embodiment, the delivery vehicle is a disposable absorbent article
having the composition of the present invention disposed on at least a
component thereof. The suitable component of an absorbent article preferably
has a skin-contacting surface such that when the article is worn, the
composition disposed on the absorbent article is placed adjacent to the
skin. Suitable components of an absorbent article may also be a secondary
layer (which does not have a surface in direct contact with the skin) that
will transfer the composition to the skin indirectly. Thus, the component of
an absorbent article suitable for such use may be a topsheet, a backsheet,
any secondary layer, a leg cuff, a side panel, a waist region, an insertable
element inserted into the absorbent article for use during wear of the
article, a specialized structure such as a bowel movement "pockets", and the
combinations thereof.
In a preferred embodiment, the delivery vehicle is a diaper having the
general structure as shown in FIG. 1
(see Original Patent). FIG. 1 is a plan view of a diaper 20 in a flat-out
state with portions of the structure being cut-away to more clearly show the
construction of the diaper 20. The portion of the diaper 20 that faces the
wearer is oriented towards the viewer. As shown in FIG. 1, the diaper 20
comprises a liquid pervious topsheet 24; a liquid impervious backsheet 26;
an absorbent core 28 positioned between at least a portion of the topsheet
24 and the backsheet 26; side panels 30; elasticized leg cuffs 32; an
elastic waist feature 34; and a fastening system generally designated 40.
The diaper 20 is shown in FIG. 1 to have a first waist region 36, a second
waist region 38 opposed to the first waist region 36 and a crotch region 37
located between the first waist region 36 and the second waist region 38.
The periphery of the diaper 20 is defined by the outer edges of the diaper
20 in which longitudinal edges 50 run generally parallel to the longitudinal
centerline 100 of the diaper 20 and end edges 52 run between the
longitudinal edges 50 generally parallel to the lateral centerline 110 of
the diaper 20.
Exemplary absorbent articles such as diapers are disclosed in U.S. Pat. No.
3,860,003 issued to Buell on Jan. 14, 1975, U.S. Pat. No. 5,151,092 issued
to Buell et al. on Sep. 29, 1992, U.S. Pat. No. 5,221,274 issued to Buell et
al. on Jun. 22, 1993, U.S. Pat. No. 5,554,145 issued to Roe et al. on Sep.
10, 1996, U.S. Pat. No. 5,569,234 issued to Buell et al. on Oct. 29, 1996,
and U.S. Pat. No. 5,580,411 issued to Nease et al. on Dec. 3, 1996, the
disclosure of each of which is incorporated herein by reference.
Exemplary training pants are disclosed in U.S. Pat. No. 5,246,433, issued to
Hasse, et al. on Sep. 21, 1993, U.S. Pat. No. 5,569,234, issued to Buell et
al. on Oct. 29, 1996, U.S. Pat. No. 6,120,487, issued to Ashton on Sep. 19,
2000, U.S. Pat. No. 6,120,489, issued to Johnson et al. On Sep. 19, 2000,
U.S. Pat. No. 4,940,464, issued to Van Gompel et al. on Jul. 10, 1990 and
U.S. Pat. No. 5,092,861, issued to Nomura et al. on Mar. 3, 1992, the
disclosure of each of these references is incorporated herein by reference.
Exemplary feminine hygiene articles are disclosed in U.S. Pat. No.
4,556,146, issued to Swanson et al. on Dec. 3, 1985, U.S. Pat. No.
4,589,876, issued to Van Tilberg on Apr. 27, 1993, U.S. Pat. No. 4,687,478,
issued to Van Tilburg on Aug. 18, 1997, U.S. Pat. No. 4,950,264, issued to
Osborn, III on Aug. 21, 1990, U.S. Pat. No. 5,009,653, issued to Osborn, III
on Apr. 23, 1991, U.S. Pat. No. 5,267,992, issued to Van Tilburg on Dec. 7,
1993, U.S. Pat. No. 5,389,094, issued to Lavash et al. on Feb. 14, 1995,
U.S. Pat. No. 5,413,568, issued to Roach et al. on May 9, 1995, U.S. Pat.
No. 5,460,623, issued to Emenaker et al. on Oct. 24, 1995, U.S. Pat. No.
5,489,283, issued Van Tilburg on Feb. 6, 1996, U.S. Pat. No. 5,569,231,
issued to Emenaker et al. on Oct. 29, 1996, and U.S. Pat. No. 5,620,430,
issued to Bamber on Apr. 15, 1997, the disclosure of each of these
references is incorporated by reference herein.
Exemplary incontinence articles are disclosed in U.S. Pat. No. 4,253,461
issued to Strickland, et al. on Mar. 3, 1981; U.S. Pat. Nos. 4,597,760 and
4,597,761 issued to Buell; the above-mentioned U.S. Pat. Nos. 4,704,115;
4,909,802 issued to Ahr, et al.; U.S. Pat. No. 4,964,860 issued to Gipson,
et al. on Oct. 23, 1990; and in U.S. Pat. No. 5,304,161 issued Apr. 19, 1994
to Noel, et al., the disclosure of each of these references is incorporated
herein.
Claim 1 of 8 Claims
1. An article comprising: a. delivery
vehicle; and b. a film forming composition applied to at least a portion
of the delivery vehicle, the composition comprising: from about 1% to
about 90% a skin conditioning agent; from about 15% to about 50% a
viscosity enhancing agent; and from about 1% to about 20% an oleophilic
film-forming agent selected from the group consisting of PVP/alpha-olefin
copolymers, acrylic copolymers, fatty acid ester/fatty acid anhydride
grafted polyolefins, and mixtures thereof; wherein the composition is
substantially anhydrous, having no more than about 10% water. ____________________________________________
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