Composition for dyeing keratin fibres, especially human keratin fibres e.g. hair, contains (a) as coupler, an N-substituted derivative of 4-hydroxy indoline of formula (I) and/or an acid addition salt, and (b) an oxidation base. In (I), R1 = e.g. 1-4C monohydroxyalkyl; 2-4C polyhydroxyalkyl; acetyl; 1-4C haloalkyl; 1-4C sulphoalkyl etc.; R2, R3 = H, halo, 1-4C alkyl, COOH, 1-4C alkoxycarbonyl or formyl; R4 = e.g. H; halo; 1-4C alkyl or alkoxy; acetylamino; furan; phenyl; 1-4C aralkyl etc.; with phenyl and aralkyl optionally substituted by e.g. halo, 1-4C alkyl, CF3, 1-4C alkoxy, amino (optionally mono- or di-substituted by e.g. 1-4C alkyl etc.) etc. Also claimed are compounds (I) per se with the proviso that when R2-R4 = H then R1 is not methoxycarbonylpropyl.
Compositions for dyeing keratinous fibers containing N-substituted 4-hydroxy indoline derivatives, and certain of these derivatives