Patent ID: 7476260

Claim:
Method of dyeing keratin-containing fibers comprising treating the fiber with at least one sulfide dye of formula wherein R 1 and R 2 each independently from each other are a residue of an organic dye; Y 1 and Y 2 each independently from each other are unsubstituted or substituted, straight-chain or branched, interrupted or uninterrupted —C 1 -C 10 alkylene-; —C 5 -C 10 cycloalkylene-; C 5 -C 10 arylene; or —C 5 -C 10 arylene-(C 1 -C 10 alkylene)-; Z 1 and Z 2 independently from each other are —C(O); —C 2 -C 12 alkenylene-; —(CH 2 CH 2 —O) 1-5 —; —C 1 -C 10 alkylene(C 5 -C 10 arylene)-; —C 5 -C 10 arylene-; —C 5 -C 10 cycloalkylene-; —C(O)O—; R 3 , R 4 and R 5 are each independently from each other hydrogen; or unsubstituted or substituted, straight-chain or branched, monocyclic or polycyclic, interrupted or uninterrupted C 1 -C 14 alkyl; C 2 -C 14 alkenyl; C 6 -C 10 aryl; C 6 -C 10 aryl-C 1 -C 10 alkyl; or C 5 -C 10 alkyl(C 5 -C 1 aryl); r, q and n independently from each other are 0 or 1, if n is O, Z 3 is hydrogen; and if n is 1, Z 3 is —S—; with the proviso that the method does not comprise treating the fiber with an enzyme of the type of a protein disulfidisomerase (EC 5.3.4.1).