dye for keratin fibres, and in particular human hair fibers containing oxidation dye precursors and heterocyclic couplers staining procedure under application of this dye, new heterocyclic couplers and a method for the production thereof.

摘要

The invention relates to a dyeing composition for keratinous fibres containing, in a cosmetically acceptable solvent medium, at least one para-type oxidation dye precursor in combination with at least one heterocyclic coupler of formula: IMAGE (I) in which R denotes a hydrogen atom, a C1-C4 radical, a C2-C4 hydroxyalkyl radical, a C3 to C6 polyhydroxyalkyl radical, or a C2-C6 alkoxyalkyl radical, Z, independently of R, denotes a C1 to C4 alkyl radical, a C2 to C4 hydroxyalkyl radical, a C3 to C6 polyhydroxyalkyl radical, a C2-C6 alkoxyalkyl radical or a trifluoroethyl radical, R1 and R2 independently of each other denote a hydrogen atom or a C1 to C4 alkyl radical, or one of the addition salts of the compound of formula (I) with an inorganic acid, a process for the oxidation dyeing of hair using this composition as well as the new couplers of formula (I) where Z is other than methyl when R1, R2 and R=H, the process for their preparation, the new intermediate compounds of formula: IMAGE (II') and the process for their preparation.