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Title: Enhanced SPF sunscreen (sprayable) formulations
comprising interpolymers of PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester
United States Patent: 6,436,377
Issued: August 20, 2002
Inventors: Hansenne; Isabelle (Westfield, NJ); Rick; Donald
W. (Dumont, NJ)
Assignee: Societe L'Oreal S.A. (Paris, FR)
Appl. No.: 791734
Filed: February 26, 2001
Abstract
Topically applicable cosmetic/dermatological compositions well suited for
both effective and SPF-enhanced UV-photoprotection of human skin, hair
and/or scalp, most preferably packaged as spray delivery systems, contain
(a) an effective UV-photoprotecting amount of at least one UV-A and/or UV-B
sunscreen, most notably the sunscreen avobenzone, and (b) an amount of the
interpolymer PVP/dimethiconylacrylate/polycarbamyl/polyglycol ester
effective to statistically significantly enhance the SPF value of said at
least one UV-A and/or UV-B or avobenzone sunscreen, formulated into (c) a
topically applicable, cosmetically/dermatologically acceptable vehicle,
diluent or carrier therefor; the subject compositions optionally contain a
thus-effective amount of an artificial/sunless tanning agent.
DETAILED DESCRIPTION OF BEST MODE AND SPECIFIC/PREFERRED EMBODIMENTS
OF THE INVENTION
More particularly according to the present invention, the subject
compositions contain (a) an effective UV-photoprotecting amount of at
least one UV-A and/or UV-B sunscreen and (b) an amount of the copolymer
PVP/dimethiconylacrylate/polycarbamyl/polyglycol ester effective to
statistically significantly enhance the SPF value of said at least one
UV-A and/or UV-B sunscreen, formulated into (c) a topically applicable,
cosmetically/dermatologically acceptable vehicle, diluent or carrier
therefor.
By "UV-A and/or UV-B sunscreen" is intended any compound or any
combination of compounds which, by mechanisms that are known per se of
absorption and/or reflection and/or scattering of UV-A and/or UV-B
radiation, prevents, or at least limits, the contact between such
radiation and a surface (skin, hair) on which this or these compounds have
been applied. Stated differently, these compounds may be UV-absorbing
organic screening agents or inorganic (nano)pigments which scatter and/or
reflect UV radiation, as well as mixtures thereof.
According to the present invention, the at least one UV-A and/or UV-B
sunscreen may comprise one or more hydrophilic organic screening agents
and/or one or more lipophilic organic screening agents and/or one or more
mineral or inorganic (nano)pigments.
The most preferred UV-photoprotecting agent according to the present
invention is the dibenzoylmethane sunscreen avobenzone, or
4-(tert-butyl)-4'-methoxydibenzoylmethane, which is very well known to
this art, is commercially available and is marketed, for example, under
the trademark "PARSOL 1789" by Givaudan. It has the structural formula:
##STR1##
Sunscreens according to the present invention which are physical blockers
reflect or scatter ultraviolet radiation. Typical examples of physical
blockers include red petrolatum, titanium dioxide, and zinc oxide. These
physical blockers have been employed in a variety of suspensions and
particle sizes and are frequently included in cosmetic formulations. A
review of physical blockers may be found at "Sun Protection Effect of
Nonorganic Materials," by S. Nakada & H. Konishi, Fragrance Journal,
Volume 15, pages 64-70 (1987), which is incorporated by reference herein.
Sunscreens according to this invention which are chemical absorbers, like
avobenzone, actually absorb harmful ultraviolet radiation. It is well
known that chemical absorbers are classified, depending on the type of
radiation they protect against, as either UV-A or UV-B absorbers. UV-A
absorbers generally absorb radiation in the 320 to 400 nm region of the
ultraviolet spectrum. UV-A absorbers include anthranilates, benzophenones,
and dibenzoyl methanes. UV-B absorbers generally absorb radiation in the
280 to 320 nm region of the ultraviolet spectrum. UV-B absorbers include
p-aminobenzoic acid derivatives, camphor derivatives, cinnamates, and
salicylates.
Classifying the chemical absorbers generally as UV-A or UV-B absorbers is
accepted within the industry. However, a more precise classification is
one based upon the chemical properties of the sunscreens. There are eight
major classifications of sunscreen chemical properties which are discussed
at length in "Sunscreens-Development, Evaluation and Regulatory Aspects,"
by N. Shaath et al., 2nd. Edition, pages 269-273, Marcel Dekker, Inc.
(1997). This discussion, in its entirety, is incorporated by reference
herein.
The sunscreens which may be formulated according to the present invention
typically comprise chemical absorbers, but may also comprise physical
blockers. Exemplary sunscreens which may be formulated into the
compositions of the present invention are chemical absorbers such as p-aminobenzoic
acid derivatives, anthranilates, benzophenones, camphor derivatives,
cinnamic derivatives, dibenzoyl methanes, .beta.,.beta.-diphenylacrylate
derivatives, salicylic derivatives, triazine derivatives, benzimidazole
compounds, bis-benzoazolyl derivatives, methylene
bis-(hydroxyphenylbenzotriazole) compounds, the sunscreen polymers and
silicones, or mixtures thereof. These are variously described in U.S. Pat.
Nos. 2,463,264, 4,367,390, 5,166,355 and 5,237,071 and in EP-0,863,145,
EP-0,517,104, EP-0,570,838, EP-0,796,851, EP-0,775,698, EP-0,878,469,
EP-0,933,376, EP-0,893,119, EP-0,669,323, GB-2,303,549, DE-1,972,184 and
WO-93/04665, also expressly incorporated by reference. Also exemplary of
the sunscreens which may be formulated into the compositions of this
invention are physical blockers such as cerium oxides, chromium oxides,
cobalt oxides, iron oxides, red petrolatum, silicone-treated titanium
dioxide, titanium dioxide, zinc oxide, and/or zirconium oxide, or mixtures
thereof.
A wide variety of sunscreens is described in U.S. Pat. No. 5,087,445,
issued to Haffey et al. on Feb. 11, 1992; U.S. Pat. No. 5,073,372, issued
to Turner et al. on Dec. 17, 1991; and Chapter VIII of Cosmetics and
Science and Technology by Segarin et al., pages 189 et seq. (1957), all of
which are incorporated herein by reference in their entirety.
Preferred among those sunscreens which may be formulated into the
compositions of the instant invention are those selected from among:
aminobenzoic acid, amyldimethyl PABA, cinoxate, diethanolamine p-methoxycinnamate,
digalloyl trioleate, dioxybenzone, 2-ethoxyethyl p-methoxycinnamate, ethyl
4-bis(hydroxypropyl)aminobenzoate,
2-ethylhexyl-2-cyano-3,3-diphenylacrylate, ethylhexyl p-methoxycinnamate,
2-ethylhexyl salicylate, glyceryl aminobenzoate, homomenthyl salicylate,
homosalate, 3-imidazol-4-ylacrylic acid and ethyl ester, methyl
anthranilate, octyldimethyl PABA, 2-phenylbenzimidazole-5-sulfonic acid
and salts, red petrolatum, sulisobenzone, titanium dioxide,
triethanolamine salicylate, N, N, N-trimethyl-4-(2-oxoborn-3-ylidene
methyl)anillinium methyl sulfate, and mixtures thereof.
Similarly preferred sunscreens active in the UV-A and/or UV-B range
include:
p-aminobenzoic acid,
oxyethylene (25 mol) p-aminobenzoate,
2-ethylhexyl p-dimethylaminobenzoate,
ethyl N-oxypropylene p-aminobenzoate,
glycerol p-aminobenzoate,
4-isopropylbenzyl salicylate,
2-ethylhexyl 4-methoxycinnamate,
methyl diisopropylcinnamate,
isoamyl 4-methoxycinnamate,
diethanolamine 4-methoxycinnamate,
3-(4'-trimethylammunium)-benzyliden-bornan-2-one methylsulfate,
2-hydroxy-4-methoxybenzophenone,
2-hydroxy-4-methoxybenzophenone-5-sulfonate,
2,4-dihydroxybenzophenone,
2,2',4,4'-tetrahydroxybenzophenone,
2,2'-dihydroxy-4,4'dimethoxybenzophenone,
2-hydroxy-4-n-octoxybenzophenone,
2-hydroxy-4-methoxy-4'-methoxybenzophenone,
.alpha.-(2-oxoborn-3-ylidene)-tolyl-4-sulfonic acid and soluble salts
thereof,
3-(4'-sulfo)benzyliden-bornan-2-one and soluble salts thereof,
3-(4'methylbenzylidene)-d,1-camphor,
3-benzylidene-d,1-camphor,
benzene 1,4-di(3-methylidene-10-camphosulfonic) acid and salts thereof
(the product Mexoryl SX described in U.S. Pat. No. 4,585,597 issued to
Lange et al. on Apr. 29, 1986),
urocanic acid,
2,4,6-tris[p-(2'-ethylhexyl-1'-oxycarbonyl)-anilino]-1,3,5-triazine,
2-[(p-(tertiobutylamido)anilino]-4,6-bis-[(p-(2'-ethylhexyl-1'-oxycarbonyl)
anilino]-1,3,5-triazine,
2,4-bis{[4-(2-ethyl-hexyloxy)]-2-hydroxy]-phenyl}-6-(4-methoxy-phenyl)-1,3,
5-triazine ("TINOSORB S" marketed by Ciba),
the polymer of N-(2 et 4)-[(2-oxoborn-3-yliden)methyl]benzyl]-acrylamide,
1,4-bisbenzimidazolyl-phenylen-3,3',5,5'-tetrasulfonic acid and salts
thereof,
the benzalmalonate-substituted polyorganosiloxanes,
the benzotriazole-substituted polyorganosiloxanes (Drometrizole
Trisiloxane),
dispersed
2,2'-methylene-bis-[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)p
henol] such as that marketed under the trademark MIXXIM BB/100 by
Fairmount Chemical, or micronized in dispersed form thereof such as that
marketed under the trademark TINOSORB M by Ciba-Geigy, and
solubilized 2,2'-methylene-bis-[6-(2H-benzotriazol-2-yl)-4-(methyl)phenol]
such as that marketed under the trademark MIXXIM BB/200 by Fairmount
Chemical.
Typically preferred among the subject sunscreens are one or more of the
following: octyl salicylate, octocrylene, and oxybenzone. Combinations of
one of more of these sunscreens is similarly preferred.
The dibenzoyl methane derivatives other than avobenzone are also preferred
sunscreens according to the present invention. These are described, for
example, in FR-2,326,405, FR-2,440,933 and EP-0,114,607, hereby expressly
incorporated by reference.
More preferred dibenzoyl methane sunscreens other than avobenzone include
(whether singly or in any combination):
2-methyldibenzoylmethane
4-methyldibenzoylmethane
4-isopropyldibenzoylmethane
4-tert.-butyldibenzoylmethane
2,4-dimethyldibenzoylmethane
2,5-dimethyldibenzoylmethane
4,4'-diisopropyldibenzoylmethane
4,4'-dimethoxydibenzoylmethane
2-methyl-5-isopropyl-4'-methoxydibenzoylmethane
2-methyl-5-tert.-butyl-4'-methoxydibenzoylmethane
2,4-dimethyl-4'-methoxydibenzoylmethane
2,6-dimethyl-4-tert. -butyl-4'-methoxydibenzoylmethane
The subject at least one UV-A and/or UV-B sunscreen is advantageously
formulated into the compositions of the invention in amounts ranging from
about 0.01% to about 10%, and preferably from about 0.1% to about 6%, by
weight thereof. Of course, depending upon the nature of the particular
formulation, higher or lower amounts may be suitable.
The judiciously selected polymeric film former PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester is also known to this art and it too is available commercially. As
indicated above, it is marketed in the United States by Hydromer Inc.
under the trademark "Aquamere S-2011."
The concentration of the interpolymer PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester formulated into the compositions of the invention advantageously
ranges from about 0.5% to about 10% by weight thereof. Also depending upon
the nature of the particular formulation, higher or lower amounts may be
suitable. However, as the Aquamere S-2011 supplied by Hydromer is a 20%
dispersion in water, to achieve a 3% active level of the polymer, for
example, 15% of the dispersion is formulated.
Thus, the present invention features topically applicable
cosmetic/dermatological compositions, and preferably sprayable
compositions, comprising both at least one UV-A and/or UV-B sunscreen,
notably avobenzone, and PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester, formulated into a topically applicable, cosmetically/dermatologically
acceptable vehicle, diluent or carrier therefor.
Concordantly, this invention features a regime or regimen for
photoprotecting human skin, hair and/or scalp against the damaging or
deleterious effects of ultraviolet irradiation, comprising topically
applying onto the skin, hair and/or scalp of a human subject, a
cosmetic/dermatological composition which comprises (a) an effective UV-photoprotecting
amount of at least one UV-A and/or UV-B sunscreen, most preferably
including avobenzone, and (b) an effective SPF-enhancing amount of the
interpolymer PVP/dimethiconylacrylate/polycarbamyl/polyglycol ester.
In a preferred embodiment of the invention, a regime or regime is featured
for photoprotecting human skin, hair and/or scalp against the
damaging/deleterious effects of ultraviolet irradiation, particularly
solar radiation, comprising spraying onto the skin, hair and/or scalp of a
human subject, a sprayable cosmetic/dermatological composition, whether
via aerosol or pump system, which comprises (a) an effective UV-photoprotecting
amount of at least one UV-A and/or UV-B sunscreen, characteristically
including avobenzone, and (b) an effective SPF-enhancing amount of the
interpolymer PVP/dimethiconylacrylate/polycarbamyl/polyglycol ester.
Also featured are concordantly UV-photoprotecting and artificial or
sunless tanning compositions comprising those constituents (a) and (b) as
indicated above, together with an effective amount of at least one
artificial/sunless tanning agent, notably dihydroxyacetone or DHA.
Consistent herewith, in vitro SPF results characteristically up to 2 times
higher than corresponding formulations not containing the PVP interpolymer
were obtained. High SPF results were also attained topically applying DHA
sunless tanning sprays containing avobenzone and PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester. It too will be appreciated that, other than enhancing SPF values
according to the invention, it is also possible to maintain a particular
SPF value of a particular composition consistent herewith, for example an
SPF value of 15, simply by formulating less of the UV-A and/or UV-B
sunscreen. Accordingly, the copolymer PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester serves not only to enhance SPF values, but also, non-quantitatively,
to maintain or adjust a particular SPF value while at the same time
formulating conspicuously less of the UV filter. Thus, methodology is now
available for providing UV-photoprotecting cosmetic/dermatological
compositions which comprise at least one UV-A and/or UV-B or avobenzone
sunscreen and having a predetermined SPF value, for example an SPF of 15,
comprising admixing and intimately formulating an amount of said at least
one UV-V and/or UV-B or avobenzone sunscreen less than that required to
confer said predetermined SPF value of 15 to said cosmetic/dermatological
composition, together with such amount of the copolymer PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester effective to elevate the SPF thereof to said predetermined value of
15.
To date, a wide variety of artificial tanning agents has been developed.
Artificial tanners provide the highly sought-after tanning or darkening
response once only available through harmful exposure to ultraviolet
radiation. DHA, in particular, has been widely utilized in cosmetics to
accomplish artificial tanning of the skin. Proteins of the epidermis have
a very high concentration of arginine, lysine, and histidine and the
reaction of skin with DHA to produce an artificial tan takes advantage of
this fact. The tanning reaction proceeds through combination with free
amino groups in skin proteins, and particularly by combination of DHA with
the free guanido group in arginine.
Preferred among those artificial tanners which are useful in the
compositions of the instant invention are those selected from the group
comprising: allose, alpha hydroxy substituted ketones such as
dihydroxyacetone, altrose, arabinose, erythrose, fructose, galactose,
glucose, glyceraldehyde, indoles, lactose, mannose, reose, ribose,
pentose, sucrose, tallose, xylose, and mixtures thereof.
Most preferred among these artificial/sunless tanners which are useful in
the compositions of the present inventions is dihydroxyacetone. In this
respect, it should be appreciated that DHA is not at all easy to
formulate, is particulary sensitive and compositions comprised thereof
tend to be quite unstable over time (as DHA tolerates but few raw
materials, e.g., carbomers). Thus, the stable formulations according to
the invention, especially those suited for spray delivery, are all the
more unexpected and surprising.
Heretofore, attempts to formulate a high SPF sunscreen spray containing
avobenzone met with difficulty; this was due to the incompatibility of
avobenzone with other sunscreen filters. To reiterate, it was also
difficult to achieve high SPF values in sprayable formulations.
Indeed, high SPF sunscreen sprays are available on the market, but these
do not contain avobenzone. High SPF values have thus been obtained by
incorporating greater amounts of UV-B absorbing sunscreens such as
octylmethoxy cinnamate. However, such formulations provide scant
protection against longer wavelength UV-A irradiation.
The compositions of the present invention can be formulated into a wide
variety of product types, including creams, dispersions, emulsions
(oil-in-water, water-in-oil, water-in-oil-in-water, and
oil-in-water-in-silicone), gels, ointments, lotions, milks, mousses,
sprays, tonics, and the like.
In a most especially preferred embodiment of the present invention, the
subject cosmetic/dermatological compositions are provided as spray
delivery systems. This because, heretofore, it was particularly difficult
to attain high SPFs with a spray. Also, because of its ease of use, the
consumer particularly appreciates a spray delivery system.
The topical cosmetic compositions of the present invention typically
comprise a carrier (vehicle or diluent) or mixture of carriers. The
carrier should be cosmetically and/or pharmaceutically acceptable, which
reflects that the carrier is suitable for topical application onto the
skin, has good aesthetic properties, is compatible with the copolymer of
the present invention, and any other components, and will not cause any
untoward safety or toxicity concerns. The carriers and additional
components used to formulate such products vary with the product type and
may be routinely chosen by one skilled in the art. The following is a
description of some of these carriers and additional components.
The compositions of the present invention can comprise a carrier, or a
mixture of carriers, suitable for topical application onto human skin. The
carriers typically constitute from about 0.5% to about 99.5% by weight,
preferably from about 5.0% to about 99.5% by weight, more preferably from
about 10.0% to about 98.0% by weight, of the composition. As used herein,
the phrase "suitable for topical application onto human skin" reflects
that the carrier does not damage or negatively affect the aesthetics of or
cause irritation to human skin.
Carriers suitable for use with the present invention include, for example,
those used in the formulation of a wide variety of product types,
including creams, dispersions, emulsions, gels, lotions, milks, mousses,
sprays, and tonics.
The carriers used herein can include a wide range of components
conventionally used in cosmetic/dermatological compositions. The carriers
can contain a solvent to dissolve or disperse the polymer. The carriers
can also contain a wide variety of additional materials including, but not
limited to, esters (such as isopropyl myristate), halogenated hydrocarbons
(such as freons), hydrocarbons (such as decene, hexane, and isobutane),
linalool, and volatile silicon derivatives (especially siloxanes such as
phenyl pentamethyl disiloxane, methoxypropyl heptamethyl
cyclotetrasiloxane, chloropropyl pentamethyl disiloxane, hydroxypropyl
pentamethyl disiloxane, octamethyl cyclotetrasiloxane, decamethyl
cyclopentasiloxane, cyclomethicone, dimethicone), and mixtures thereof.
Mousses and aerosol sprays can also include any of the conventional
propellants to deliver the material as a foam, in the case of a mousse, or
as a fine, uniform spray, in the case of an aerosol spray. Examples of
suitable propellants include materials such as hydrofluorinated compounds,
dichlorodifluoromethane, difluoroethane, dimethylether, isobutane,
n-butane, propane, or trichlorofluromethane. A tonic or spray product
having a low viscosity may also include an emulsifying agent. Examples of
suitable emulsifying agents are anionic surfactants, cationic surfactants,
nonionic surfactants, and mixtures thereof. Fluorosurfactants are
especially preferred, particularly if the product is a preferred spray
composition and most especially if it is a spray composition having a
relatively low level of volatile organic solvents, such as alcohols, and
relatively high levels of water (i.e., in excess of about 10%, by weight,
water). If such an emulsifying agent is included, it is preferably present
at a level of from about 0.01% to about 7.5% by weight of the composition.
The level of propellant can be adjusted as desired, but is generally from
about 3% to about 30% by weight of mousse compositions and from about 15%
to about 50% by weight of the aerosol spray compositions.
Suitable spray compositions are well known in the art and include
conventional, non-aerosol pump sprays, i.e., "atomizers," aerosol
containers or cans having propellant, as described above, and also pump
aerosol containers utilizing compressed air as the propellant. Pump
aerosol containers are disclosed, for example, in U.S. Pat. No. 4,077,441,
issued to Olofsson on Mar. 7, 1978, and U.S. Pat. No. 4,850,517, issued to
Ter Stege on Jul. 25, 1989, both incorporated herein by reference.
A wide variety of additional components can be employed in the topical
cosmetic/dermatological compositions herein. The compositions of the
present invention can comprise a safe and effective amount of a
pharmaceutical additive or adjuvant. The phrase "safe and effective"
connotes an amount of an active agent high enough to significantly or
positively modify the condition to be treated, but low enough to avoid
serious side effects (at a reasonable benefit/risk ratio) within the scope
of sound medical judgment. A safe and effective amount of the
pharmaceutical active agent will vary with the specific active species,
the ability of the composition to penetrate the active species through the
skin, the amount of composition to be applied, the particular condition
being treated, the age and physical condition of the patient being
treated, the severity of the condition, the duration of the treatment, the
nature of concurrent therapy, and like factors.
Useful pharmaceutical active agents which may be conjointly administered
according to in the present invention include antimicrobial drugs:
antibacterials, antifungals, antiprotozoans, and antivirals. Antimicrobial
drugs preferred for inclusion in the compositions of the present invention
comprise pharmaceutically acceptable salts of .beta.-lactam drugs,
amanfadine, amikacin, capreomycin, chlorhexidine, chlortetracycline,
ciprofloxacin, clindamycin, doxycycline, erythromycin, ethambutol,
gentamicin, kanamycin, lineomycin, methacycline, methenamine,
metronidazole, miconazole, minocycline, neomycin, netilmicin, norfloxacin,
oxytetracycline, paramomycin, pentamidine, quinolone drugs, streptomycin,
tetracycline, tobramycin, and triclosan.
The subject cosmetic/dermatological compositions can contain various
emulsifiers when formulated as emulsions. These emulsifiers are useful for
emulsifying the various carrier components of the compositions herein.
Suitable emulsifiers can include any of a wide variety of nonionic,
cationic, anionic, and zwitterionic emulsifiers disclosed in the prior
patents and other references. See McCutcheon's, Detergents and
Emulsifiers, North American Edition (1986), published by Allured
Publishing Corporation; U.S. Pat. No. 5,011,681, issued to Ciotti et al.
on Apr. 30, 1991; U.S. Pat. No. 4,421,769, issued to Dixon et al. on Dec.
20, 1983; and U.S. Pat. No. 3,755,560, issued to Dickert et al. on Aug.
28, 1973. These four publications are incorporated herein by reference in
their entirety.
Suitable emulsifier types include acyl lactylates, alkyl phosphates,
carboxylic acid copolymers, esters and ethers of glucose, esters of
glycerin, esters of propylene glycol, esters of sorbitan anhydrides,
esters of sorbitol, ethoxylated ethers, ethoxylated alcohols, fatty acid
amides, fatty acid esters of polyethylene glycol, fatty esters of
polypropylene glycol, polyoxyethylene fatty ether phosphates, soaps and
mixtures thereof.
Preferred emulsifiers can include, but are not limited to, ceteareth-20,
ceteth-10, cetyl phosphate, diethanolamine cetyl phosphate, glyceryl
stearate, PEG-100 stearate, polyethylene glycol 20 sorbitan monolaurate,
polyethylene glycol 5 soya sterol, polysorbate 60, polysorbate 80,
potassium cetyl phosphate, PPG-2 methyl glucose ether distearate,
steareth-20, and mixtures thereof.
Typically preferred among these emulsifiers which are useful in the
compositions of the present inventions is PPG-2 isoceteth-20 acetate
(described in U.S. Pat. No. 4,559,226, issued to Fogel et al.).
The subject cosmetic/dermatological compositions can also contain various
emollients. Examples of suitable emollients include, but are not limited
to, highly branched hydrocarbons, non-polar carboxylic acid and alcohol
esters, volatile and non-volatile silicone oils, and mixtures thereof.
See, U.S. Pat. No. 4,919,934, issued to Deckner et al. on Apr. 24, 1990,
which is incorporated by reference in its entirety.
Typically preferred among these emollients which are useful in the
compositions of the present inventions are one or more of the following:
octyldodecyl neopentanoate and propylene glycol isoceteth-3 acetate.
A variety of additional components can be incorporated into the subject
cosmetic/dermatological compositions. Non-limiting examples of these
additional components include cationic polymers and thickeners, chelators,
gums and thickeners, low pH thickening agents, polymers for enhancing the
film-forming properties and substantivity of the composition, sequestrants,
skin penetrating aids, suspending agents, vitamins and derivatives
thereof, preservatives and aesthetic components.
Exemplary preservatives, which are conventional in this art and which
prevent or retard microbial growth and thus protect cosmetic products from
spoilage, are set forth at CFTA International Cosmetic Ingredient
Dictionary and Handbook, seventh edition, 2, 1654 (1997).
The cosmetic/dermatological compositions of the present invention are
administered in conventional fashion to provide the desired benefit. Such
methods of use generally involve topical and preferably spray application
of an effective amount of the composition onto the skin, which then is
allowed to remain until absorbed into or removed from the skin.
Again, enhanced SPF values are provided hereby via the specific addition
of the PVP/dimethiconylacrylate/polycarbamyl/polyglycol ester copolymer
into the specific sunscreen formulation, for example SPF values greater
than 40 and usually even greater than 50. While not wishing to be bound to
or by any particular theory, it is believed that the PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester interpolymer serves the function of imparting more effectiveness to
the avobenzone sunscreen by maintaining a conspicuously thick, continuous
sunscreen film over the skin.
Accordingly, high levels of UV-B absorbing filters are not required to
attain enhanced SPF values. The subject avobenzone formulations are thus
unique in concordantly providing enhanced SPF values and high UV-A
photoprotection.
Too, other materials described as film formers have been incorporated into
sunscreen formulations. The film former quite usual in this art is PVP/eicosane
copolymer; nonetheless, the increase in SPF is not nearly as dramatic as
that provided by PVP/dimethiconylacrylate/polycarbamyl/polyglycol ester.
Indeed, similar spray formulations containing similar levels of PVP/eicosane
copolymer provided average in vitro SPF values of about 30, as compared to
SPF values greater than 45 with PVP/dimethiconylacrylate/polycarbamyl/polyglycol
ester.
Once again, given that film formers have to date been shown to provide
conspicuously modest increases in SPF values, the very high SPF values
according to the present invention are most unexpected, especially
considering that the subject formulations containing the UV-A filter
avobenzone do not contain high levels of UV-B absorbing filters such as
octylmethoxy cinnamate.
High SPF-enhancing effects are also provided hereby in formulations
containing sunscreens and dihydroxyacetone, formulations that are normally
difficult to impart high SPF values thereto.
Claim 1 of 32 Claims
What is claimed is:
1. A regime/regimen for improvedly UV-photoprotecting human skin, hair
and/or scalp against the deleterious effects of ultraviolet irradiation,
comprising topically applying thereon (a) an effective UV-photoprotecting
amount of at least one UV-A and/or UV-B sunscreen and (b) an amount of the
interpolymer PVP/dimethiconylacrylate/polycarbamyl/polyglycol ester
effective to significantly enhance the SPF value of said at least one UV-A
and/or UV-B sunscreen, formulated into (c) a topically applicable,
cosmetically/dermatologically acceptable vehicle, diluent or carrier
therefor.
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