Patent ID: 7481847

Claim:
A dye composition comprising, in a medium suitable for dyeing human keratin fibers: (a) at least one direct dye chosen from cationic direct hydrazone dyes of formula (I) and tautomeric forms thereof: [A-C(R 3 )═N—N(R 1 )—B] + X (I) wherein: R 1 and R 3 , which may be identical or different, are chosen from hydrogen and linear or branched C 1 -C 10 alkyl radicals optionally bearing a hydroxyl group; A is a fused or non-fused, optionally substituted cationic heterocycle chosen from pyrimidinone, indole, and benzothiazole rings; the ring A being linked to the carbon of C(R 3 ) via a carbon atom; B is a saturated or unsaturated, optionally substituted tricycle chosen from dibenzofurans, carbazoles, anthraquinones, and dibenzothienyls; the saturated or unsaturated tricycle B being linked to the nitrogen atom of the hydrazone function via a carbon atom of one of the three rings; X is chosen from anions and mixtures of anions that are cosmetically acceptable; (b) at least one cosmetic agent chosen from thickening polymers and surfactants.