| abstract |
The invention relates to a process for dyeing keratinous fibres, which consists in applying to these fibres a composition containing, in a suitable medium for dyeing, at least one coupler of formula: where R1 denotes hydrogen or alkyl, R2 and R3 denote hydrogen, alkyl, COOR' where R' is alkyl or hydrogen, at least one of the groups R2 and R3 denoting hydrogen, R4 denotes hydrogen, alkyl, hydroxyalkyl, polyhydroxyalkyl or aminoalkyl, Z1 and Z2 denote hydrogen, alkyl, hydroxyl, halogen, alkoxy, at least one of the groups Z1 and Z2 is other than hydrogen at least one oxidation dye precursor, at least one oxidizing agent, the pH of the composition applied to the fibres being higher than 7. |