Patent ID: 7354571

Claim:
A topically applicable cosmetic/dermatological composition suited for photoprotecting keratin materials, comprising an effective UV-photoprotecting amount of at least one methyltrialkylsilane compound having the formula (I) below: in which: B is a chromophoric group having either of formulae (1) and (2) below: R 1 and R 2 , which may be identical or different, are each a linear or branched C 1 -C 12 alkyl radical, optionally halogenated or containing a double bond or a triple bond, or a phenyl or benzyl radical; R 3 is a radical R 1 or R 2 or a group B; n is an integer ranging from 0 to 3 inclusive; X is â€”Oâ€” or â€”NR 5 â€”; A is a hydrogen atom, a linear or branched C 1 -C 4 alkyl radical, a group SiR 1 R 2 R 3 in which R 1 , R 2 and R 3 are as defined above, with the proviso that R 3 is other than B; the radical Râ€² is a hydrogen atom, a linear or branched C 1 -C 10 alkyl radical, a linear or branched C 2 -C 8 alkenyl radical or an Si(CH 3 ) 3 group; the radicals Râ€³, which may be identical or different, are each a hydroxyl radical, a linear or branched C 1 -C 10 alkyl radical, a linear or branched C 2 -C 8 alkenyl radical, a linear or branched C 1 -C 10 alkoxy radical, with the proviso that Râ€³ may together form with an adjacent Râ€³ or ORâ€², an alkylidenedioxy group in which the alkylidene group contains one or two carbon atoms, or an â€”OSi(CH 3 ) 3 group; Z, Zâ€² and Zâ€³, which may be identical or different, are each a hydrogen atom, a linear or branched C 1 -C 4 alkyl radical; a group â€”(Câ•O)R 4 , â€”(Câ•O)OR 4 , â€”SO 2 R 5 , â€”(Câ•O)NR 6 R 7 , â€”CN or â€”(Câ•O)XCHASiR 1 R 2 R 3 in which R 1 , R 2 and R 3 are as defined above, with the proviso that R 3 is other than B, and with the further proviso that: (i) at least one of the radicals Zâ€² and Zâ€³ is other than hydrogen, and (ii) when Zâ€² is â€”SO 2 R 5 , then Zâ€³ is other than a â€”CN group; R 4 is a hydrogen atom or a linear or branched C 1 -C 20 alkyl radical; R 5 is a C 1 -C 20 alkyl radical or a C 6 -C 12 aryl radical; R 6 and R 7 , which may be identical or different, are each a hydrogen atom or a C 1 -C 4 alkyl radical; with the further proviso that: Zâ€² and Zâ€³ may also together form a Meldrum acid of formula (3) below: in which R 8 and R 9 , which may be identical or different, are each hydrogen or a linear or branched C 1 -C 20 alkyl radical; and R 8 and R 9 may also together form a C 5 -C 12 ring member, formulated into a topically applicable, cosmetically/dermatologically acceptable medium therefor.