titleOfInvention |
Use, as a coupler, of 2,4-diamino-1,3-dimethoxybenzene or one of its salts, in combination with oxidation dye precursors, for dyeing human hair, hair dyeing composition containing the said coupler and process for preparing the said coupler |
abstract |
The invention relates to the use, by way of a coupler, of 2,4-diamino-1,3-dimethoxybenzene or one of its addition salts with an acid, in combination with at least one oxidation dye precursor of the para type, for dyeing keratinous fibres and especially human hair. The hair dyeing compositions according to the invention contain, in a cosmetically acceptable aqueous vehicle, 0.05 to 3.5% by weight of 2,4-diamino-1,3-dimethoxybenzene or one of its salts, which imparts to the hair strong blue colorations when it is combined with p-phenylenediamines or red colorations when it is combined with p-aminophenols, in an oxidizing alkaline medium. |