Para-aminophenols containing compositions for dyeing of keratin fibres, dyeing process, para-aminophenols and a method for their preparation

摘要

A composition for dyeing keratin fibres, especially human hair, comprises a dyeing medium containing, as oxidation base, at least one of fused bicyclic para-aminophenol derivatives of formula (I) and their acid addition salts. In (I), R1 = H, 1-4C alkyl or 1-4C trifluoroalkyl; R2, R3 = H, 1-4C alkyl or 1-4C monohydroxyalkyl; X, Y, Z = C, N, O or S, the X-Y and Y-Z bonds being single or double. 4-Amino-2,2-dimethyl-2,3-dihydro-benzofuran-1-ol (Ia), 7-amino-1-methyl-1H-indol-4-ol (Ib) and their acid addition salts are new compounds. Also claimed are (i) a dyeing process for keratin fibres, involving applying (A) and developing the colour at acid, neutral or alkaline pH using an oxidising agent (II), where (II) is added to (A) immediately before use or is applied simultaneously or sequentially in a separate oxidising composition; (ii) a multi-compartment dyeing kit having a first compartment containing (A) and a second compartment containing an oxidising composition; and (iii) the use of ( I) as oxidation base in compositions for oxidation of keratin fibres.