| abstract |
A method for dyeing keratin fibres wherein a composition containing at least one coupler in a medium suitable for dyeing is applied to said fibres. Said coupler has formula (I), wherein R1? is hydrogen or alkyl; R2? and R3? are hydrogen, alkyl or COOR' where R' is alkyl or hydrogen with at least one of groups R2? and R3? being hydrogen; R4? is hydrogen, alkyl, hydroxyalkyl, polyhydroxyalkyl or aminoalkyl; Z1? and Z2? are hydrogen, alkyl, hydroxyl, halogen or alkoxy with at least one of groups Z1? and Z2? being different from hydrogen. Said composition further contains at least one oxidation dye precursor and at least one oxidizing agent, the pH of the composition applied to the fibres being higher than 7. |