Patent ID: 7018426

Claim:
An agent for oxidative dyeing of keratin fibers, said agent comprising a combination of at least one 4,5-diaminopyrazole derivative of formula (I), (II) or (III), or a salt thereof with an organic or inorganic acid: wherein R 1 and R 2 each, independently of each other; represent hydrogen, a linear or branched C 1 –C 6 alkyl group, an optionally substituted phenyl group or a linear or branched C 2 –C 4 -hydroxyalkyl group; with the proviso that R 1 is not methyl if R 2 is hydrogen; R3 represents a halogen atom, a linear or branched C 1 –C 4 alkyl group or a linear or branched C 1 –C 4 alkoxy group and R 4 represents hydrogen, a linear or branched C 1 –C 4 alkyl group or a linear or branched C 2 –C 4 hydroxyalkyl group; R 5 represents hydrogen, a linear or branched C 1 –C 6 alkyl group, a C 1 –C 4 hydroxyalkyl group, a C 1 –C 4 aminoalkyl group, a C 1 –C 8 alkylamino group, a di(C 1 –C 8 )alkylamino group, a C 1 –C 4 alkylamino-(C 1 –C 4 )alkyl group or a di(C 1 –C 4 ) alkylamino-(C 1 –C 4 )alkyl group, an aryl group or a heteroaryl group; R 6 and R 7 may be the same or different and independently of each other, each represent hydrogen, a linear or branched C 1 –C 6 alkyl group, an aryl group, a heteroaryl group, a carboxylic acid group, a carboxylic ester group, an optionally substituted carboxylic acid amide group, a hydroxy group or a C 1 –C 4 hydroxyalkyl group or R 2 and R 3 jointly form an optionally substituted C 1 –C 6 alkylene group; Z is a C 1 –C 10 alkyl diradical, which is optionally interrupted by a hetero atom, an aromatic diradical or a heteroaromatic diradical, which is optionally condensed with one or two benzene rings and/or substituted by a hydroxy group or a C 1 –C 6 alkyl group, or a diradical of formula —Ar(Alk) n —Ar—, in which Ar is an optionally substituted aryl or heteroaryl group, Alk is a —CH 2 group and n is a whole number from 0 to 6; and x and y, independently of one another are equal to 0 or 1; and at least one resorcinol derivative, of formula (IV), which is substituted in at a 4 position thereof; wherein R 8 is a linear or branched C 1 –C 8 alkyl group, a linear or branched C 1 –C 8 hydroxyalkyl group, a linear or branched C 1 –C 4 alkoxy-(C 1 –C 8 )alkyl group or a linear or branched C 1 –C 8 aminoalkyl group; and R 9 represent hydrogen, a linear or branched C 1 –C 8 alkyl group, a linear or branched C 1 –C 8 hydroxyalkyl group, a linear or branched C 1 –C 4 alkoxy-C 1 –C 8 alkyl group or a linear or branched C 1 –C 8 aminoalkyl group.