Patent ID: 8551191

Claim:
An agent for dyeing and optionally simultaneously lightening keratin fibers, the agent comprising a dicationic azo dye of a Formula (I): in which Y is either for ═CH— or a nitrogen atom, R 1 and R 2 independently of one another are a C 1 -C 6 alkyl group, a C 2 -C 6 alkenyl group, a hydroxy C 1 -C 6 alkyl group, a polyhydroxy C 2 -C 6 alkyl group, a C 1 -C 6 alkoxy C 2 -C 6 alkyl group, a cyano C 1 -C 6 alkyl group, an aryl group or an aryl C 1 -C 6 alkyl group, R 3 and R 4 independently of one another are a hydrogen atom, a C 1 -C 6 alkyl group, a fluorine, chlorine, bromine or iodine halogen atom, a C 1 -C 6 alkoxy group, an amino group, a C 1 -C 6 alkylamino group, a di-C 1 -C 6 alkylamino group, a hydroxyl group or that R 3 and R 4 together form a 5-, 6- or 7-membered, saturated or unsaturated ring that can optionally comprise additional heteroatoms or can carry additional substituents, n and m independently of one another are a whole number from 1 to 6, R 5 is a hydrogen atom, a C 1 -C 6 alkoxy group, a fluorine, chlorine, bromine or iodine halogen atom, a hydroxyl group, a C 1 -C 6 alkoxy C 2 -C 6 alkyloxy group, a nitrile group, an aryl group or a heteroaryl group, X − is a monovalent anion.