U.S. patent application number 09/761827 was filed with the patent office on 2001-10-04 for photostabilized sunscreen compositions comprising dibenzoylmethane compounds and benzylidenecamphor-substituted silanes/organosiloxanes.
Invention is credited to Forestier, Serge, Richard, Herve.
Application Number | 20010026789 09/761827 |
Document ID | / |
Family ID | 9528561 |
Filed Date | 2001-10-04 |
United States Patent
Application |
20010026789 |
Kind Code |
A1 |
Richard, Herve ; et
al. |
October 4, 2001 |
Photostabilized sunscreen compositions comprising dibenzoylmethane
compounds and benzylidenecamphor-substituted
silanes/organosiloxanes
Abstract
Improvedly photostable, topically applicable
cosmetic/dermatological sunscreen compositions well suited for
enhanced photoprotection of human skin and/or hair against the
damaging effects of UV-A and UV-B irradiation, particularly solar
radiation, comprise (i) a photoprotecting effective amount of at
least one dibenzoylmethane UV-screening compound, and (ii) an
amount of at least one silane or organosiloxane substituted by a
benzylidenecamphor functional group effective to photostabilize
said at least one dibenzoylmethane UV-screening compound (i).
Inventors: |
Richard, Herve; (Villepinte,
FR) ; Forestier, Serge; (Claye Souilly, FR) |
Correspondence
Address: |
Norman H. Stepno
BURNS, DOANE, SWECKER & MATHIS, L.L.P.
P.O. Box 1404
Alexandria
VA
22313-1404
US
|
Family ID: |
9528561 |
Appl. No.: |
09/761827 |
Filed: |
January 18, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09761827 |
Jan 18, 2001 |
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09350910 |
Jul 12, 1999 |
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6200552 |
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Current U.S.
Class: |
424/59 ; 424/400;
424/401; 424/60 |
Current CPC
Class: |
C07F 7/081 20130101;
C07F 7/21 20130101; A61K 8/893 20130101; C07F 7/0838 20130101; A61K
2800/57 20130101; A61K 2800/52 20130101; A61Q 17/04 20130101; A61K
8/35 20130101; A61K 8/585 20130101 |
Class at
Publication: |
424/59 ; 424/60;
424/400; 424/401 |
International
Class: |
A61K 007/42; A61K
007/44; A61K 007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 10, 1998 |
FR |
98-08937 |
Claims
What is claimed is:
1. A method for photostabilizing a topically applicable
cosmetic/dermatological sunscreen composition suited for the
uv-photoprotection of human skin and/or hair comprising a
photoprotecting effective amount of at least one dibenzoylmethane
UV-screening compound, said method comprising admixing into said
composition an amount of at least one silane or organosiloxane
substituted by a benzylidenecamphor functional group effective to
photostabilize said at least one dibenzoylmethane UV-screening
compound.
2. The method as defined by claim 1, wherein said at least one
silane or organosiloxane substituted by a benzylidenecamphor
functional group has the structural formula (I): 14in which the
radicals R.sub.1, which may be identical or different, are each a
hydrogen atom, an OH radical, a saturated or unsaturated, linear or
branched, C.sub.1-C.sub.10 alkyl radical, a linear or branched
C.sub.1CO.sub.10 alkoxy radical or an --OSi(CH.sub.3).sub.3
radical, with the proviso that two adjacent groups R.sub.1 may
together form an alkylidenedioxy group in which the alkylidene
radical contains 1 or 2 carbon atoms; a is an integer ranging from
1 to 3; A is a hydrogen atom or a radical of the formula --L--W
wherein L is a divalent radical of formula (IIa) or (lIb) below:
--CH.sub.2--CHR.sub.2--[C(R.sub.3).sub.2].sub.m--(CO).sub.n--(O).sub.o--(-
Z).sub.p--(Y).sub.q-- (IIa)
--CH=CR.sub.2--[C(R.sub.3).sub.2].sub.m--(CO)-
.sub.n--(O).sub.o--(Z).sub.p--(Y).sub.q-- (IIb) in which the
radicals R.sub.2 and R.sub.3, which may be identical or different,
are each a hydrogen atom or a linear or branched C.sub.1-C.sub.5
alkyl radical, Z is a linear or branched, saturated or unsaturated
C.sub.1-C.sub.6 diyl radical, optionally substituted with a
hydroxyl or linear or branched, saturated or unsaturated
C.sub.2-C.sub.8 alkyl radical, Y is --O--, --NR.sub.4--,
--SO.sub.2NH--, --(CO)O--, --(CO)NH-- or --O(CO)NH--, wherein
R.sub.4 is a hydrogen atom or a C.sub.1-C.sub.5 alkyl radical; m is
an integer ranging from 0 to 10; n is 0 or 1; o is 0 or 1; p is 0
or 1; q is 0 or 1; A.sub.1 is a hydrogen atom or a radical
--L.sub.1--W in which the radical L.sub.1 has the definition of L,
with the proviso that, when q=1, then Y is --SO.sub.2NH--, with the
further proviso that only one of the two radicals A and A.sub.1 is
a hydrogen atom; W is a radical of formula (1), (2) or (3) below:
15in which the radicals R.sub.6, which may be identical or
different, are each a linear or branched C.sub.1-C.sub.30 alkyl,
phenyl, 3,3,3-trifluoropropyl or trimethylsilyloxy radical, at
least 80%, by number, of the radicals R.sub.6 being methyl
radicals; the radicals B, which may be identical or different, are
each a radical R.sub.6 or a radical X of the formula below: 16in
which R.sub.1, L, L.sub.1 and a are as defined above; r is an
integer ranging from 0 to 200, inclusive, and s is an integer
ranging from 0 to 50, inclusive, and, if s=0, at least one of the
two symbols B is X; u is an integer ranging from 1 to 10,
inclusive, and t is an integer ranging from 0 to 10, inclusive,
with the proviso that t+u is greater than or equal to 3.
3. The method as defined in claim 2, wherein in formula (I), at
least one of the following conditions is satisfied: R.sub.1=H,
OCH.sub.3, CH.sub.3 or two adjacent radicals R.sub.1 together form
a methylenedioxy group; R.sub.2=H or CH.sub.3, n=0, q=1.
4. The method as defined by claim 2, wherein in formula (I), at
least one of the following conditions is satisfied: R.sub.6 is
methyl; B is methyl; r ranges from 5 to 20, inclusive; s ranges
from 2 to 15, inclusive; t+u ranges from 3 to 10, inclusive; m=1;
R.sub.3 is a hydrogen atom or a methyl radical.
5. The method as defined by claim 2, wherein in formula (I),
s=0.
6. The method as defined by claim 2, wherein said at least one
compound having the formula (I) is selected from among those of the
following structural formulae: 17
7. The method as defined by claim 2, wherein in formula (I), p is
equal to 1 and the radical Z is a linear or branched, saturated or
unsaturated C.sub.1-C.sub.6 diyl radical substituted by a hydroxyl
or linear or branched, saturated or unsaturated C.sub.2-C.sub.8
alkyl radical.
8. The method as defined by claim 7, wherein said at least one
formula (I) compound has the structural formula (7): 18
9. The method as defined by claim 2, wherein in formula (I), W is a
radical of formula (3) and n=0.
10. The method as defined by claim 9, wherein said at least one
compound having the formula (I) is selected from among those of the
following structural formulae: 19
11. The method as defined by claim 2, wherein said at least one
dibenzoylmethane UV-screening compound comprises
2-methyldibenzoylmethane- , 4-methyldibenzoylmethane,
4-isopropyldibenzoylmethane, 4-tert-butyldibenzoylmethane,
2,4-dimethyldibenzoylmethane, 2,5-dimethyldibenzoylmethane, 4,4'-
diisopropyldibenzoylmethane, 4,4'-dimethoxydibenzoylmethane,
4-tert-butyl-4'-methoxydibenzoylmethane,
2-methyl-5-isopropyl-4'-methoxydibenzoylmethane,
2-methyl-5-tert-butyl-4'- -methoxydibenzoylmethane,
2,4-dimethyl-4'-methoxydibenzoylmethane, and/or
2,6-dimethyl-4-tert-butyl-4'-methoxydibenzoylmethane.
12. The method as defined by claim 11, wherein said at least one
dibenzoylmethane UV-screening compound comprises
4-(tert-butyl)-4'-methox- ydibenzoylmethane.
13. The method as defined by claim 11, wherein said at least one
dibenzoylmethane UV-screening compound comprises
4-isopropyldibenzoylmeth- ane.
14. The method as defined by claim 1, wherein said composition is
formulated into a topically applicable,
cosmetically/dermatologically acceptable vehicle, diluent or
carrier therefor.
15. The method as defined by claim 1, wherein said composition
comprises from 0.01%to 10% by weight of said at least one
dibenzoylmethane UV-screening compound.
16. The method as defined by claim 1, wherein said composition
comprises from 0.01% to 6% by weight of said at least one
dibenzoylmethane UV-screening compound.
17. The method as defined by claim 15, wherein said composition
comprises at least 0.5% by weight of said at least one substituted
silane or organosiloxane.
18. The method as defined by claim 15, wherein said composition
comprises from 0.5% to 20% by weight of said at least one
substituted silane or organosiloxane.
19. A compound having the structural formula (10): 20
20. A compound having the structural formula (11): 21
21. A compound having the structural formula (12): 22
22. The method as defined by claim 1, wherein said composition
comprises an oil-in-water emulsion.
23. The method as defined by claim 1, wherein said composition
comprises a water-in-oil emulsion.
24. The method as defined by claim 1, wherein said composition
further comprises at least one additional hydrophilic or lipophilic
organic UV-A and/or UV-B sunscreen.
25. The method as defined by claim 24, wherein said composition
further comprises at least one cinnamic derivative, salicylic
derivative, triazine derivative, benzotriazole derivative,
benzimidazole derivative, benzophenone derivative,
.beta.,.beta.-diphenylacrylate derivative, p-aminobenzoic acid
derivative, sunscreen polymer, or sunscreen silicone.
26. The method as defined by claim 1, wherein said composition
further comprises a photoprotecting effective amount of
particulates of at least one inorganic pigment or nanopigment.
27. The method as defined by claim 26, wherein said at least one
pigment or nanopigment comprises titanium dioxide, zinc oxide, iron
oxide, zirconium oxide, cerium oxide, or mixture thereof.
28. The method as defined by claim 1, wherein said composition
further comprises at least one active agent for the artificial
tanning and/or browning of human skin.
29. The method as defined by claim 1, wherein said composition
further comprises at least one cosmetically acceptable adjuvant or
additive.
30. The method as defined by claim 29, wherein said at least one
adjuvant or additive comprises a fat, organic solvent, ionic or
nonionic thickening agent, softener, antioxidant, anti-free-radical
antioxidant, opacifying agent, stabilizing agent, emollient,
silicone, hydroxy acid, anti-foaming agent, hydrating agent,
vitamin, fragrance, preservative, surfactant, filler, sequestering
agent, polymer, propellant, basifying of acidifying agent, dye
colorant, or mixture thereof.
31. The method as defined by claim 1, wherein said composition
comprises a nonionic vesicle dispersion, emulsion, cream, milk,
gel, cream gel, ointment, suspension, dispersion, powder, solid
stick, foam or spray.
32. The method as defined by claim 1, wherein said composition
comprises a makeup.
33. The method as defined by claim 32, wherein said composition
comprises an anhydrous or aqueous solid or paste, emulsion,
suspension, or dispersion.
34. The method as defined by claim 1, wherein said composition
comprises a shampoo, lotion, gel, emulsion, non-ionic vesicle
dispersion, hair lacquer, or rinse.
Description
CROSS-REFERENCE TO PRIORITY APPLICATION
[0001] This application is a divisional of application Ser. No.
09/350,910, filed Jul. 12, 1999, now allowed, incorporated by
reference herein in its entirety and relied upon, which claims
priority under 35 U.S.C. .sctn.119 of FR-98/08937, filed Jul. 10,
1998, assigned to the assignee hereof and hereby expressly
incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field of the Invention
[0003] The present invention relates to improving the
photostability of at least one dibenzoylmethane sunscreen compound
with respect to UV radiation, by intimately admixing therewith an
effective photostabilizing amount of a silane or organosiloxane
compound bearing a benzylidenecamphor substituent.
[0004] 2. Description of the Prior Art
[0005] It is known to this art that light radiation with
wavelengths of from 280 nm to 400 nm promotes tanning of the human
epidermis, and that irradiation with wavelengths more particularly
ranging from 280 to 320 nm, i.e., UV-B irradiation, causes erythema
and skin burns which can be harmful to the development of a natural
tan. For these reasons, as well as for aesthetic reasons, a
constant demand exists for controlling this natural tanning and,
also, the coloration of the skin; such UV-B radiation should thus
be screened from the skin.
[0006] It is also known to this art that UV-A irradiation, with
wavelengths of from 320 to 400 nm, which tans the skin, is apt to
induce an adverse change therein, in particular in the case of
sensitive skin or skin which is continually exposed to solar
radiation. UV-A radiation in particular causes a loss of elasticity
of the skin and the appearance of wrinkles, promoting premature
aging. Such irradiation promotes triggering of the erythemal
reaction or enhances this reaction in certain individuals and may
even be the source of phototoxic or photoallergic reactions. Thus,
for aesthetic and cosmetic reasons such as conserving the skins'
natural elasticity, for example, an ever-increasing number of
subjects wish to control the effect of UV-A rays on their skin. It
is thus desirable to also screen UV-A radiation from the skin.
[0007] In this regard, one particularly advantageous class of UV-A
screening agents currently includes dibenzoylmethane derivatives,
and in particular 4-(tert-butyl)-4'-methoxydibenzoylmethane, which
have high intrinsic absorption power. These dibenzoylmethane
derivatives, which are compounds that are well known per se as
screening agents that are active in the UV-A range, are
particularly described in FR-A-2,326,405 and FR-A-2,440,933, as
well as in EP-A-0,114,607; 4-(tert-butyl)-4'-methoxydi-
benzoylmethane is moreover commercially available under the
trademark "PARSOL 1789" from Givaudan.
[0008] Unfortunately, it has been determined that dibenzoylmethane
derivatives are compounds that are relatively sensitive to
ultraviolet radiation (especially UV-A radiation), namely, more
specifically, they exhibit an annoying tendency to be degraded more
or less rapidly under the influence of such radiation. Thus, this
substantial lack of photochemical stability of dibenzoylmethane
derivatives in the face of the ultraviolet radiation to which they
are by nature intended to be subjected, does not guarantee constant
protection during prolonged exposure to the sun, such that, in a
restricting manner, repeated applications at regular and close time
intervals must be carried out by the user in order to obtain
effective protection of the skin against UV radiation.
[0009] Thus, EP-A-0,709,080 describes combining dibenzoylmethane
derivatives with benzalmalonate derivatives in order to reduce the
photoinstability of said dibenzoylmethane derivatives. Nonetheless,
the photostabilization of dibenzoylmethane derivatives with respect
to UV radiation constitutes, to date, a problem which has not yet
been solved completely satisfactorily.
[0010] FR-2,607,996 and WO-94/04131 describe combining
dibenzoylmethane derivatives with hydrocarbon-based
benzylidenecamphor derivatives such as
3-(4-methylbenzylidene)camphor in order to reduce the
photoinstability of said dibenzoylmethane derivatives.
[0011] Another difficulty, independent of the one indicated above,
encountered with dibenzoylmethane derivatives is that these are
lipophilic sunscreen agents with the particular feature, and also
present the disadvantage of being solid at room temperature.
Accordingly, formulating same into antisun cosmetic compositions
entails certain constraints as regards their processing, in
particular for determining solvents for properly dissolving same,
whether alone or in combination with other screening agents. In
this regard, oils have been typically employed such as esters, and
more particularly C.sub.12-C.sub.15 alkyl benzoates ("Finsolv TN"
marketed by Finetex), or triglycerides, and in particular
C.sub.8-C.sub.12 fatty acid triglycerides ("Miglyol 812" marketed
by Huls), but these various products exhibit solubilizing
properties with respect to the aforesaid screening agents that
remain insufficient.
[0012] Sunscreen formulations based on dibenzoylmethane derivatives
and on 3-(4-methylbenzylidene) camphor as described in FR-2,607,996
and WO-94/04131 do not obviate this problem of solubility of said
dibenzoylmethane derivatives completely satisfactorily.
SUMMARY OF THE INVENTION
[0013] It has now unexpectedly and surprisingly been found that
formulating the dibenzoylmethane derivatives indicated above with
an effective amount of a silane or organosiloxane compound
containing a benzylidenecamphor substituent, substantially and
markedly improves the photochemical stability (or photostability)
of these same dibenzoylmethane derivatives.
[0014] It has also been determined that the silane or
organosiloxane compounds containing a benzylidenecamphor functional
group according to the present invention are effective
photostabilizing agents, which is also very surprising compared
with the known hydrocarbon-based organic screening agents derived
from benzylidenecamphor, and constitute a family of solvents which
are particularly noteworthy for the screening agents of
dibenzoylmethane derivative type such as, for example,
4-(tert-butyl)-4'-methoxydibenzoylmethane; this permits, for an
equal amount of solvent, formulating greater amounts of screening
agents.
[0015] Thus, the present invention features enhancing the stability
of at least one dibenzoylmethane compound with respect to UV
radiation, by intimately formulating therewith an effective
photostabilizing amount of a silane or organosiloxane derivative
bearing a benzylidenecamphor substituent.
[0016] The cosmetic and/or dermatological compositions according to
this invention present the advantage of being particularly
photostable, even after prolonged exposure to UV-A and UV-B
radiation. Such radiation can be of natural origin (sunlight) or
artificial origin (UV lamp).
[0017] The present invention, thus, also features formulating a
silane or organosiloxane compound containing a benzylidenecamphor
functional group into a cosmetic or dermatological composition
including at least one dibenzoylmethane sunscreen compound, to
enhance the stability of said dibenzoylmethane sunscreen with
respect to UV radiation.
DETAILED DESCRIPTION OF BEST MODE AND SPECIFIC/PREFERRED
EMBODIMENTS OF THE INVENTION
[0018] More particularly according to the present invention, the
subject dibenzoylmethane sunscreens are well known per se and are
described, in particular, in FR-A-2,326,405, FR-A-2,440,933 and
EP-A-0,114,607.
[0019] Consistent herewith, it is intended, of course, to formulate
one or more of said dibenzoylmethane compounds into the
compositions of the invention.
[0020] Among the dibenzoylmethane derivatives suitable for
formulation according to the present invention, particularly
exemplary are:
[0021] 2-methyldibenzoylmethane;
[0022] 4-methyldibenzoylmethane;
[0023] 4-isopropyldibenzoylmethane;
[0024] 4-tert-butyldibenzoylmethane;
[0025] 2,4-dimethyldibenzoylmethane;
[0026] 2,5-dimethyldibenzoylmethane;
[0027] 4,4'-diisopropyldibenzoylmethane;
[0028] 4,4'-dimethoxydibenzoylmethane;
[0029] 4-tert-butyl-4'-methoxydibenzoylmethane;
[0030] 2-methyl-5-isopropyl-4'-methoxydibenzoylmethane;
[0031] 2-methyl-5-tert-butyl-4'-methoxydibenzoylmethane,;
[0032] 2,4-dimethyl-4'-methoxydibenzoylmethane;
[0033] 2,6-dimethyl-4-tert-butyl-4'-methoxydibenzoylmethane;
and
[0034] 4,4'-dimethoxydibenzoylmethane.
[0035] Among the dibenzoylmethane derivatives compounds indicated
above, most particularly preferred is
4-(tert-butyl)-4'-methoxydibenzoylmethane, in particular that
marketed under the trademark "Parsol 1789" by Givaudan. This
sunscreen agent has the following structural formula: 1
[0036] Another dibenzoylmethane derivative which is preferred
according to the present invention is 4-isopropyldibenzoylmethane.
This sunscreen agent is marketed under the trademark "Eusolex 8020"
by Merck, and has the following structural formula: 2
[0037] The subject dibenzoylmethane derivative(s) are
advantageously present in the compositions stabilized in accordance
with the present invention in contents generally ranging from 0.01%
to 10% by weight, and preferably in contents ranging from 0.3% to
5% by weight, relative to the total weight of the composition.
[0038] A second compound in the compositions according to the
invention comprises a silane or organosiloxane compound substituted
by a benzylidenecamphor functional group. These compounds are known
to this art and are described, as well as processes for the
synthesis thereof, in EP-A-0,325,881, EP-A-0,335,777 and
EP-A-0,712,855.
[0039] The silane or organosiloxane compound bearing a
benzylidenecamphor substituent according to the present invention
preferably has the structural formula (I) below: 3
[0040] in which the radicals R.sub.1, which may be identical or
different, are each a hydrogen atom, an OH radical, a saturated or
unsaturated, linear or branched, C.sub.1-C.sub.10 alkyl radical, a
linear or branched C.sub.1-C.sub.10 alkoxy radical or an
--OSi(CH.sub.3).sub.3 radical, with the proviso that two adjacent
groups R.sub.1 may together form an alkylidenedioxy group in which
the alkylidene radical contains 1 or 2 carbon atoms; a is an
integer ranging from 1 to 3; A is a hydrogen atom or a radical of
formula --L--W such that L is a divalent radical of formula (IIa)
or (IIb) below:
--CH.sub.2--CHR.sub.2--[C(R.sub.3).sub.2].sub.m--(CO).sub.n--(O).sub.o--(Z-
).sub.p--(Y).sub.q-- (IIa)
--CH=CR.sub.2--[C(R.sub.3).sub.2].sub.m--(CO).sub.n--(O).sub.o--(Z).sub.p--
-(Y).sub.q-- (IIb)
[0041] wherein R.sub.2 and R.sub.3, which may be identical or
different, are each a hydrogen atom or a linear or branched
C.sub.1-C.sub.5 alkyl radical, Z is a linear or branched, saturated
or unsaturated C.sub.1-C.sub.6 diyl radical, optionally substituted
with a hydroxyl or linear or branched, saturated or unsaturated
C.sub.2-C.sub.8 alkyl radical, Y is --O--, --NR.sub.4--,
--SO.sub.2NH--, --(CO)O--, --(CO)NH-- or --O(CO)NH--, wherein
R.sub.4 is a hydrogen atom or a C.sub.1-C.sub.5 alkyl radical; m is
an integer ranging from 0 to 10; n is 0 or 1; o is 0 or 1; p is 0
or 1; q is 0 or 1; A.sub.1 is a hydrogen atom or a radical
--L.sub.1--W in which the radical L.sub.1 has the definition of L,
with the proviso that when q=1, then Y represents --SO.sub.2NH--,
with the further proviso that only one of the two radicals A and
A.sub.1 is a hydrogen atom; W is a radical of formula (1), (2) or
(3) below: 4
[0042] in which the radicals R.sub.6, which may be identical or
different, are each a linear or branched C.sub.1-C.sub.30 alkyl,
phenyl, 3,3,3-trifluoropropyl or trimethylsilyloxy radical, at
least 80%, by number, of the radicals R.sub.6 being methyl
radicals; the radicals B, which may be identical or different, are
each a radical R.sub.6 or a radical X of the formula below: 5
[0043] in which R.sub.1, L, L.sub.1 and a are as defined above; r
is an integer ranging from 0 to 200, inclusive, and s is an integer
ranging from 0 to 50, inclusive, and, if s=0, at least one of the
two symbols B is X; u is an integer ranging from 1 to 10,
inclusive, and t is an integer ranging from 0 to 10, inclusive,
with the proviso that t+u is greater than or equal to 3.
[0044] Among the above compounds, particularly preferred is the
family of compounds which has at least one, preferably all, of the
following characteristics:
[0045] R.sub.1=H, OCH.sub.3, CH.sub.3 or two adjacent radicals
R.sub.1 form a methylenedioxy radical,
[0046] R.sub.2=H or CH.sub.3,
[0047] n=0,
[0048] q=1.
[0049] Among such compounds, preferred are those which have at
least one, preferably all, of the following characteristics:
[0050] R.sub.6 is methyl,
[0051] B is methyl,
[0052] r ranges from 5 to 20, inclusive,
[0053] s ranges from 2 to 15, inclusive,
[0054] t+u ranges from 3 to 10, inclusive,
[0055] m=1, and
[0056] R.sub.3 is a hydrogen atom or a methyl radical.
[0057] These compounds and the process for preparing same are
described, for example, in EP-A-0,335,777.
[0058] A second family of preferred compounds comprises the
compounds of formula (I) in which s=0.
[0059] Exemplary compounds of formula (I) which are particularly
preferred are those of the following structural formulae: 6
[0060] Among the compounds of formula (I) , certain of these are
novel and constitute another aspect of the present invention.
[0061] This is the case for the compounds of formula (I) as defined
above in which p is 1 and the radical Z is a linear or branched,
saturated or unsaturated C.sub.1-C.sub.6 diyl radical substituted
by a hydroxyl or linear or branched, saturated or unsaturated
C.sub.2-C.sub.8 alkyl radical. Exemplary of these specific
compounds is the compound (7) as described above.
[0062] Another family of novel compounds of formula (I) includes
the silane compounds in which W is a radical of formula (3) and n
is equal to 0. Among such compounds, the compounds (10), (11) and
(12) as described above are exemplary.
[0063] According to the invention, by the expression "effective
amount of silane or organosiloxane compound bearing a
benzylidenecamphor substituent" is intended an amount which is
sufficient to provide an appreciable and significant improvement in
the photostability of the dibenzoylmethane derivative(s) contained
in the composition. The minimum amount of stabilizer to be
formulated, which can vary depending on the nature of the
cosmetically acceptable support (vehicle, diluent or carrier)
selected for the composition, can be determined without any
difficulty via a conventional test for measuring photostability, as
described in FR-A-2,607,700.
[0064] The silane or organosiloxane compounds bearing a
benzylidenecamphor substituent are generally present in the
compositions according to the invention at a content at least equal
to 0.5% by weight, relative to the total weight of the composition.
Even more preferably, this content ranges from 0.5% to 20% by
weight relative to the total weight of the composition.
[0065] Nonetheless, the cosmetic and/or dermatological compositions
of the present invention can contain one or more complementary
hydrophilic or lipophilic sunscreens that are active in the UV-A
and/or UV-B range (absorbers). These complementary screening agents
are advantageously selected from among cinnamic derivatives,
salicylic derivatives, benzophenone derivatives, benzotriazole
derivatives, benzimidazole derivatives, triazine derivatives,
benzalmalonate derivatives, .beta..beta.'-diphenylacrylate
derivatives, p-aminobenzoic acid derivatives, and the screening
polymers and screening silicones described in WO-93/04665. Other
examples of organic sunscreens are set forth in EP-A-0,487,404.
[0066] The compositions according to the invention can also contain
agents for artificially tanning and/or browning the skin
(self-tanning agents), such as, for example, dihydroxyacetone
(DHA).
[0067] The cosmetic and/or dermatological compositions according to
the invention can also contain pigments or nanopigments (average
size of the primary particles: generally ranging from 5 nm to 100
nm, preferably from 10 to 50 nm) of coated or uncoated metal
oxides, such as, for example, nanopigments of titanium dioxide
(amorphous or crystallized in rutile and/or anatase form), of iron
oxide, of zinc oxide, of zirconium oxide or of cerium oxide, which
are all photoprotective agents that are well known per se, which
act by physically blocking out (reflecting and/or scattering) the
UV radiation. Conventional coating agents are, moreover, alumina
and/or aluminum stearate. Such coated or uncoated metal oxide
nanopigments are described, in particular, in EP-A-0,518,772 and
EP-A-0,518,773.
[0068] The compositions of this invention can also comprise
conventional cosmetic additives and adjuvants selected, in
particular, from among fatty substances, organic solvents, ionic or
nonionic thickeners, softeners, antioxidants, anti-free radical
agents, opacifiers, stabilizers, emollients, silicones, hydroxy
acids, antifoaming agents, moisturizers, vitamins, fragrances,
preservatives, surfactants, fillers, sequestering agents, polymers,
propellants, basifying or acidifying agents, colorants, dyes or any
other ingredient usually used in the cosmetics and/or
dermatological field, in particular for the manufacture of antisun
compositions in the form of emulsions. Too, any additional
ingredient liable to be introduced into the compositions in
accordance with the invention must be such that it does not
substantially affect or disrupt the photostabilizing effect exerted
by the silane or organosiloxane compounds containing a
benzylidenecamphor function with respect to the dibenzoylmethane
derivatives.
[0069] Fatty substances can include an oil or a wax or mixtures
thereof. By the term "oil" is intended a compound which is liquid
at room temperature. By the term "wax" is intended a compound which
is solid or substantially solid at room temperature and whose
melting point is generally greater than 35.degree. C.
[0070] Exemplary oils include the mineral oils (petroleum jelly);
plant oils (sweet almond oil, macadamia oil, blackcurrant pip oil,
jojoba oil); and synthetic oils such as perhydrosqualene, fatty
alcohols, fatty acids or fatty esters (such as C.sub.12-C.sub.15
alkyl benzoate marketed under the trademark "Finsolv TN" by
Finetex, octyl palmitate, isopropyl lanolate, triglycerides,
including capric/caprylic acid triglycerides), oxyethylenated or
oxypropylenated fatty esters and ethers; silicone oils
(cyclomethicone, polydimethylsiloxanes or PDMS) or fluoro oils, and
polyalkylenes.
[0071] Exemplary waxy compounds include paraffin, carnauba wax,
beeswax and hydrogenated castor oil.
[0072] And exemplary organic solvents include the lower alcohols
and polyols.
[0073] The thickeners are advantageously selected, in particular,
from among crosslinked polyacrylic acids, and modified or
unmodified guar gums and cellulose gums, such as hydroxypropyl guar
gum, methylhydroxyethylcellulose and hydroxpropylmethyl
cellulose.
[0074] The compositions according to the invention are easily
formulated according to techniques which are well known to this
art, in particular those intended for the preparation of emulsions
of oil-in-water or water-in-oil type.
[0075] This compositions can be, in particular, in the form of a
simple or complex (O/W, W/O, O/W/O or W/O/W) emulsion, such as a
cream or a milk, or in the form of a gel or a cream-gel, a powder
or a solid tube and can optionally be packaged as an aerosol and
can be in the form of a mousse or a spray.
[0076] The compositions according to the invention are preferably
formulated as oil-in-water emulsions.
[0077] When it is an emulsion, the aqueous phase thereof can
comprise a nonionic vesicle dispersion prepared according to known
techniques (Bangham, Standish and Watkins, J. Mol. Biol., 13, 238
(1965), FR-2,315,991 and FR 2,416,008).
[0078] The cosmetic and/or dermatological compositions of the
invention are useful for protecting the human epidermis or the hair
against ultraviolet radiation, as an antisun composition or as a
makeup product.
[0079] When the cosmetic compositions according to the invention
are for protecting the human epidermis against UV rays, or as an
antisun (sunscreen) composition, these can be formulated as
suspensions or dispersions in solvents or fatty substances, in the
form of a nonionic vesicle dispersion or in the form of an
emulsion, preferably of oil-in-water type, such as a cream or a
milk, in the form of an ointment, a gel, a cream-gel, a solid tube,
a stick, a lotion, an aerosol mousse or a spray.
[0080] When the cosmetic compositions according to the invention
are used for protecting the hair, same can be in the form of a
shampoo, a lotion, a gel, an emulsion or a nonionic vesicle
dispersion, and can constitute, for example, a rinse-out
composition, to be applied before or after shampooing, before or
after dyeing or bleaching, before, during or after permanent-waving
or straightening the hair, a styling or treating lotion or gel, a
blow-drying or hairsetting lotion or gel, or a permanent-waving,
straightening, dyeing or bleaching composition for the hair.
[0081] When the subject compositions are used as makeup product for
the eyelashes, the eyebrows or the skin, such as an epidermal
treatment cream, a foundation, a lipstick, an eyeshadow, a face
powder, a mascara or an eyeliner, same can be in solid or pasty,
anhydrous or aqueous form, such as oil-in-water or water-in-oil
emulsions, nonionic vesicle dispersions or alternatively
suspensions.
[0082] For illustrative purposes, for the antisun formulations in
accordance with the invention which contain a support of
oil-in-water emulsion type, the aqueous phase (in particular
comprising the hydrophilic screening agents) generally constituting
from 50% to 95% by weight, preferably from 70% to 90% by weight,
relative to the total weight of the overall formulation, the oily
phase (in particular comprising the lipophilic screening agents)
generally constitutes from 5% to 50% by weight, preferably from 10%
to 30% by weight, relative to the entire formulation, and the
(co)emulsifier(s) generally represent(s) from 0.5% to 20% by
weight, preferably from 2% to 10% by weight, relative to the entire
formulation.
[0083] In order to further illustrate the present invention and the
advantages thereof, the following specific examples are given, it
being understood that same are intended only as illustrative and in
nowise limitative.
EXAMPLE 1
Preparation of the compound of formula (4)
[0084] 7
[0085] 37.53 g (0.169 mol) of heptamethyltrisiloxane were added
dropwise over 30 minutes to a solution of
3-(4-allyloxy-benzylidene)-1,7,7-trimeth-
ylbicyclo[2.2.1]heptan-2-one, prepared in accordance with Example 8
of FR-A-2,430,938 (50 g, 0.169 mol), and of catalyst (complex
containing 3%-3.5% by weight of Pt in cyclovinylmethylsiloxane
marketed by Huls Petrarch PC085: 200 .mu.l) in 140 ml of dry
toluene heated to 80.degree. C. The mixture was maintained at this
temperature for 6 hours. The reaction mixture was concentrated. The
residue was taken up in dichloromethane and this solution was
passed through a bed of Celite. The pale yellow oil obtained was
crystallized from heptane. 31 g (yield: 41%) of the target compound
of this Example 1 were thus obtained in the form of a white
powder:
[0086] m.p.: 47.degree.-48.degree. C.
[0087] UV (95% ethanol) .lambda..sub.max=318 nm,
.epsilon..sub.max=27,000
[0088] Elemental analysis for C.sub.27H.sub.46O.sub.4Si.sub.3:
[0089] Theory: C62.50 H8.94 Si16.24
[0090] Found: C62.43 H9.00 Si16.26
EXAMPLE 2
Preparation of the compound of formula (5)
[0091] 8
[0092] 12.2 g (0.055 mol) of heptamethyltrisiloxane were added
dropwise over 30 minutes to a solution of
1,7,7-trimethyl-3-[4-(2-methylallyloxy)b- enzylidene]
bicyclo[2.2.1]heptan-2-one (15.5 g, 0.05 mol) and catalyst (complex
containing 3%-3.5% by weight of Pt in cyclovinylmethylsiloxane
marketed by Huls Petrarch PC085:100 .mu.l) in 35 ml of dry toluene
heated to 80.degree. C. The mixture was maintained at this
temperature for 3 hours. The reaction mixture was concentrated and,
after chromatography on silica (eluent: 50/50
heptane/dichloromethane), 23 g (yield: 86%) of a colorless oil of
the target compound of this Example 2 were obtained:
[0093] UV (ethanol) .lambda..sub.max=320 nm,
.epsilon..sub.max=26,200
[0094] Elemental analysis for C.sub.28H.sub.48O.sub.4Si.sub.3:
[0095] Theory: C63.10 H9.08 Si15.81
[0096] Found: C63.02 H9.00 Si15.64
EXAMPLE 3
Preparation of the compound of formula (6)
[0097] 9
[0098] 50 g (0.117 mol) of
.alpha.,.omega.-dodecamethyl-hexasiloxane were added dropwise over
1 hour, 30 minutes, to a solution of
1,7,7-trimethyl-3-[4-(2-methylallyl-oxy)benzylidene]bicyclo[2.2.1]
heptan-2-one (69.8 g, 0.235 mol) and of catalyst (complex
containing 3%-3.5% by weight of Pt in cyclovinylmethylsiloxane
marketed by Huls Petrarch PC085: 100 .mu.l) in 110 ml of dry
toluene heated to 80.degree. C. The mixture was maintained at this
temperature for 1 hour, 30 minutes. The reaction mixture was
concentrated and, after chromatography on silica (eluent: 98/2
heptane/ethyl acetate followed by gradient up to 50/50
heptane/ethyl acetate), 47.5 g (yield: 40%) of a viscous, pale
yellow oil of the target compound of this Example 3 was
obtained:
[0099] UV (ethanol) .lambda..sub.max=320 nm,
.epsilon..sub.max=26,200
[0100] Elemental analysis for C.sub.52H.sub.86O.sub.9Si.sub.6:
1 Theory: C61.01 H8.47 Si16.46 Found: C61.04 H8.52 Si16.10
EXAMPLE 4
Preparation of the compound of formula (7)
[0101] 10
[0102] A mixture of
3-(4-hydroxybenzylidene)1,7,7-trimethyl-N-bicyclo [2.2.1]
heptan-2-one (10 g, 0.039 mol) and 3-glycidyloxypropyl-bis-(trime-
thylsiloxy) methylsilane (14.8 g, 0.044 mol) in the presence of
tetrabutylammonium bromide (0.6 g) was maintained at 110.degree. C.
for 6 hours, while bubbling nitrogen there-through. The crude oil
obtained was chromatographed on silica (eluent: 20/80 ethyl
acetate/heptane) to give, in medium fractions, 10 g (yield: 43%) of
the target compound of this Example 4 in the form of a colorless
oil:
[0103] UV (ethanol) .lambda..sub.max=318 nm,
.epsilon..sub.max=26,900
[0104] Elemental analysis for C.sub.30H.sub.52O.sub.6Si.sub.3:
2 Theory: C60.76 H8.84 Si14.21 Found: C60.54 H8.87 Si13.96
EXAMPLE 5
Preparation of the compound of formula (10)
[0105] 11
[0106] 5.37 g (0.0525 mol) of diethylmethylsilane were added
dropwise over 20 minutes to a solution of
1,7,7-trimethyl-3-[4-(2-methylallyloxy)benzyl- idene]
bicyclo[2.2.1] heptan-2-one (15.5 g, 0.05 mol) and of catalyst
(complex containing 3%-3.5% by weight of Pt in
cyclovinylmethylsiloxane marketed by Huls Petrarch PC085: 200
.mu.l) in 10 ml of dry toluene heated to 70.degree. C. The mixture
was maintained at this temperature for 48 hours. The reaction
mixture was concentrated and, after chromatography on silica
(eluent: heptane/ dichloromethane), 11.8 g (yield: 57%) of a
viscous colorless oil of the target compound of this Example 5,
which crystallized, were obtained:
[0107] m.p.: 39.degree.-40.degree. C.
[0108] UV (ethanol) .lambda..sub.max=320 nm,
.epsilon..sub.max=28,230
[0109] Elemental analysis for C.sub.26H.sub.40O.sub.2Si:
3 Theory: C75.67 H9.77 Si6.81 Found: C75.42 H9.77 Si7.10
EXAMPLE 6
Preparation of the compound of formula (11)
[0110] 12
[0111] (a) First step: Preparation of 3-methoxy-4-(3-
trimethylsilanylpropyloxy) benzaldehyde
[0112] 3-chloropropyltrimethylsilane (33.14 g, 0.22 mol) was added
dropwise over 20 minutes to a mixture of vanillin (30.4 g, 0.2 mol)
and potassium carbonate (30.4 g, 0.22 mol) in 150 ml of dry DMF
heated to 80.degree. C. under nitrogen. The mixture was maintained
for 4 hours at 95.degree.-110.degree. C. The reaction mixture was
cooled and poured into ice-cold water. The aqueous phase was
extracted three times with dichloromethane. The organic phases were
dried over sodium sulfate and concentrated under vacuum. After
distillation under vacuum (0.04 mm Hg), 47.5 g (yield: 89%) of
3-methoxy-4-(3-trimethylsilanylpropyloxy) benzaldehyde were
obtained in the form of a slightly pinkish oil distilling at
112.degree.-114.degree. C. and employed without further
purification in the following step.
[0113] (b) Second step: Preparation of the target compound of this
Example 6
[0114] A mixture of camphor (8.36 g, 0.055 mol) and NaH at 50% in
oil (2.64 g, 0.055 mol; rinsed with dry heptane and then with dry
dimethoxyethane) in 40 ml of dry dimethoxyethane was heated at
80.degree. C. for 30 minutes. The step (a) derivative (13.32 g,
0.05 mol) dissolved in 30 ml of dimethoxyethane was added dropwise
thereto over 20 minutes at 80.degree. C. The mixture was maintained
under stirring at 80.degree. C. for 3 hours. After cooling, the
mixture was poured into ice-cold water. The precipitate obtained
was washed with water and then recrystallized from ethanol to give
12.4 g (yield: 62%) of the target compound of this Example 6 in the
form of a white powder:
[0115] m.p.: 79.degree.-80.degree. C.
[0116] UV (ethanol) .lambda..sub.max=331 nm,
.epsilon..sub.max=21,300
[0117] Elemental analysis for C.sub.24H.sub.36O.sub.3Si:
4 Theory: C71.95 H9.06 Si7.01 Found: C71.80 H9.05 Si6.80
EXAMPLE 7
Preparation of the compound of formula (12)
[0118] 13
[0119] (a) First step: preparation of
4-(3-trimethylsilanylpropyloxy)benza- ldehyde
[0120] 3-chloropropyltrimethylsilane (33.14 g, 0.22 mol) was added
dropwise over 10 minutes to a mixture of 4-hydroxybenzaldehyde
(24.4 g, 0.2 mol) and potassium carbonate (30.4 g, 0.22 mol) in 150
ml of dry DMF maintained at 120.degree. C. under nitrogen. The
mixture was maintained for 2 hours, 30 minutes, at
120.degree.-130.degree. C. The reaction mixture was cooled and
poured into ice-cold water. The aqueous phase was extracted 3 times
with dichloromethane. The organic phases were dried over sodium
sulfate and concentrated under vacuum. After distillation under
vacuum (0.2 mmHg), 40.5 g (yield: 86%) of
4-(3-trimethylsilanylprop- yloxy) benzaldehyde were obtained in the
form of a colorless oil distilling at 110-114.degree. C. and
employed without further purification in the following step.
[0121] (b) Second step: preparation of the target compound of this
Example 7
[0122] A mixture of camphor (15.2 g, 0.1 mol) and NaH at 50% in oil
(4.8 g, 0.1 mol); rinsed with dry heptane and then with dry
dimethoxyethane) in 50 ml of dry dimethoxyethane were heated at
80.degree. C. for 30 minutes. The above step (a) derivative (21.3
g, 0.09 mol) dissolved in 30 ml of diethoxyethane was added
dropwise thereto over 20 minutes at 80.degree. C. The mixture was
maintained under stirring at 80.degree. C. for 2 hours. After
cooling, the mixture was poured into ice-cold water. The
precipitate obtained was washed with water and then recrystallized
from ethanol to give 20.6 g (yield: 60%) of the target compound of
this Example 7 in the form of a white powder:
[0123] m.p.: 100.degree.-101.degree. C.
[0124] UV (ethanol) .lambda..sub.max=320 nm,
.epsilon..sub.max=26,530
[0125] Elemental analysis for C.sub.23H.sub.34O.sub.2Si:
5 Theory: C74.54 H9.25 Si7.58 Found: C74.62 H9.17 Si7.80
EXAMPLE 8
[0126] The compositions described below were formulated (the
amounts are expressed as a % by weight relative to the total weight
of the composition):
[0127] Composition A (comparative)
6 Ingredients Composition A Isopropyl myristate 30 Parsol 1789 1.5
Ethanol q.s. 100
[0128] Composition A' (comparative)
7 Ingredients Composition A' Isopropyl myristate 30
3-(4-methylbenzylidene- 5 camphor (Eusolex 6300) Parsol 1789 1.5
Ethanol q.s. 100
[0129] The following compositions B to E (according to the present
invention) also comprised 5% by weight of a silicone
benzylidenecamphor compound of this invention.
8 Composition Composition Composition Composition Ingredients B C D
E Isopropyl 30 30 30 30 myristate Parsol 1789 1.5 1.5 1.5 1.5
Silicone Example 5 Example 6 Example 7 Example 2 benzyl-idene-
camphor according to the invention Ethanol qs 100 qs 100 qs 100 qs
100
[0130] For each of these compositions, the percentage of residual
Parsol 1789 (4-tert-butyl-4'-methoxydibenzoylmethane) after
irradiation with UV according to the following procedure was
determined: for each formula, three control samples and three test
samples were prepared. 2 .mu.l/cm.sup.2 of formula were spread by
hand onto frosted glass plates. The plates were then exposed in a
chamber, the temperature of which was adjusted to about
35.degree.-40.degree. C. (Heraeus Suntest CPS), for the time
required to obtain an exposure, expressed relative to the UVA flux,
of 30 J/cm.sup.2, in order to simulate natural UV irradiation by
storing the control plates in darkness during the period of
irradiation of the other plates.
[0131] The samples were then assayed in the following manner: the
screening agents were extracted by immersing each plate in 50 g of
ethanol in order to dissolve the screening agents. The plates and
the solvent containing the screening agents were then treated with
ultrasound for 15 minutes in order to ensure efficient extraction.
The solutions obtained were analyzed by spectrophotometry at the
.lambda..sub.max of each of the screening agents.
[0132] For each test formula, the level of residual
4-tert-butyl-4'-methoxydibenzoylmethane after irradiation was given
by the ratio of its concentration in the irradiated sample to its
concentrated in the non-irradiated sample.
[0133] The results, as a percentage of
4-tert-butyl-4'-methoxydibenzoylmet- hane remaining, are reported
in the Table below:
9 TABLE OD % of residual Composition Parsol 1789 Composition A
(comparative) 5 .+-. 1 Composition A' (comparative) 58.8
Composition B (invention) 76 .+-. 6 Composition C (invention) 81
.+-. 6 Composition D (invention) 79 .+-. 7 Composition E
(invention) 69 .+-. 3
[0134] These results clearly evidenced that the presence of a
silane or organosilxane compound containing a benzylidenecamphor
group improved the photostability of
4-tert-butyl-4'-methoxydibenzoylmethane.
[0135] These results also evidenced that the photostability of
4-tert-butyl-4'-methoxydibenzoyl-methane obtained in the presence
of a hydrocarbon-based benzylidenecamphor compound was further
improved by formulating therewith, in place of the latter compound,
silane or organosiloxane compounds containing a benzylidenecamphor
group.
[0136] While the invention has been described in terms of various
preferred embodiments, the skilled artisan will appreciate that
various modifications, substitutions, omissions, and changes may be
made without departing from the spirit thereof. Accordingly, it is
intended that the scope of the present invention be limited solely
by the scope of the following claims, including equivalents
thereof.
* * * * *