Azomethine direct dyes or reduced from direct dyes azomethine obtained from 2-alkylresorcinols precursors, and hair dyeing process using such dyes or precursors.

摘要

The compound of formula (I) or (II) salts thereof with an organic or mineral acid, geometrical isomers thereof, tautomers thereof and solvates thereof such as hydrates; wherein in formula (I) or (II): * R1, which may be identical or different, represent: - a chlorine atom; - an alkyl radical (C1-C3) optionally substituted with one or more hydroxyl group; - a radical alkoxy (C1-C3) optionally substituted with one or more hydroxyl group; * R2 represents a (C1-C3) radical; * X, which may be identical or different, represent: - a hydroxyl radical; - one -NR3R4 radical representing R3 and R4, independently of one another: i) a hydrogen atom; ii) an alkyl radical C1-C5 optionally substituted with one or more groups selected from hydroxyl, (C1-C3), amino, (C1-C3), dialkylamino (C1-C3), aminocarbonyl, -COOH carboxylic -SO3H groups sulfonic, trialkylammonium (C1-C3) alkyl and (C1-C3) imidazolium; - a pyrrolidinyl radical optionally substituted by a group selected from hydroxyl, (C1-C3), amino, (C1-C3), dialkylamino (C1-C3), trialkylammonium (C1-C3) and alkyl (C1-C3) imidazolium ; - one piperidine radical optionally substituted with a group selected from hydroxyl, (C1-C3), amino, (C1-C3), dialkylamino (C1-C3), trialkylammonium (C1-C3) and alkyl (C1-C3) imidazolium ; * N represents an integer between 0 and 3 inclusive; understood that when X and / or R3 and / or R4 comprise a cationic group, the electrical neutrality of the compounds of formula (I) is achieved with an anionic counterion or a mixture of counterions that are cosmetically acceptable, for instance chlorides, bromides and sulphates.