abstract |
A composition for the oxidation dyeing of keratinous fibers containing at least one coupler selected from N-substituted 4-hydroxyindole compounds and acid addition salt thereofs and at least one oxidation base, N-substituted 4-hydroxyindole compounds, a process for synthesizing these substituted compounds, their use as couplers for the oxidation dyeing of keratinous fibers in combination with at least one oxidation base, as well as dyeing processes employing them. |