Abstract: A dyeing composition for keratinous fibers and in particular for human keratinous fibers such as hair, comprising, in a suitable dyeing medium, at least one oxidation dye precursor chosen from 3-methyl-para-aminophenol, 2-methyl-para-aminophenol and 2-hydroxymethyl-para-aminophenol and their addition salts with an acid; at least one coupling agent chosen from the 2-methyl-5-aminophenols of formula (I): ##STR1## where R denotes hydrogen, methyl, ethyl, .beta.-hydroxyethyl or .gamma.-hydroxypropyl, and their addition salts with an acid; and at least one ortho-aminophenol chosen from ortho-aminophenol and 3-acetylamino-6-aminophenol or one of their addition salts with an acid. A dyeing process incorporates development by an oxidizing agent.

Abstract: Processes for the oxidative dyeing of keratinus fibers with compositions which comprise benzimidazole derivatives as couplers, at least one metaphenylenediaxnine and at least one para or ortho oxidation dye precursor, the benzimidazole derivative corresponding to the formula: ##STR1## in which: R.sub.1 represents a hydrogen atom or a C.sub.1 -C.sub.4 alkyl radical;R.sub.2 represents a hydrogen atom or a C.sub.1 -C.sub.4 alkyl radical or a phenyl radical;R.sub.3 represents a hydroxyl, amino or methoxy radical;R.sub.4 represents a hydrogen atom or a hydroxyl or methoxy or C.sub.1 -C.sub.4 alkyl radical;with the proviso that:when R.sub.3 denotes NH.sub.2, it occupies position 4;when R.sub.3 is at position 4, R.sub.4 is at position 7;when R.sub.3 is at position 5, then R.sub.4 is at position 6.

Abstract: The invention relates to a dyeing composition for keratinous fibres and in particular for human keratinous fibres such as hair, comprising, in a suitable media for dyeing, at least one oxidation dye precursor chosen from 3-methyl-para-aminophenol, 2-methyl-para-aminophenol and 2-hydroxymethyl-para-aminophenol, and their addition salts with an acid; at least one coupling agent chosen from the 2-methyl-5-aminophenols of formula (I): ##STR1## in which R is methyl, ethyl, .beta.-hydroxyethyl or .gamma.-hydroxypropyl, and their addition salts with an acid; and at least one para-phenylenediamine and/or one bis(phenylalkylenediamine) or one of their addition salts with an acid as oxidation dye precursor.

Abstract: A process for dyeing keratinous fibres, wherein a mixture of at least one para-aminophenol of formula: ##STR1## in which, Y is oxygen or sulphur,R is alkyl, monohydroxyalkyl, polyhydroxyalkyl, or their acid addition salts, and 6-hydroxyindole, 7- hydroxyindole or mixtures thereof, is applied to the fibers, the colour being delayed at alkaline pH with an oxidising agent.

Abstract: The invention relates to a dyeing composition for keratinous fibres and in particular for human keratinous fibres such as hair, comprising, in a suitable medium for dyeing, at least one oxidation dye precursor chosen from 3-methyl -para-aminophenol, 2-methyl-para-aminophenol and 2-hydroxymethyl-para-aminophenol, and their addition salts with an acid, as coupling agent, at least 2-methyl-5-aminophenol, or one of its addition salts with an acid; and at least one para-phenylenediamine and/or one bis-(phenylalkylenediamine) or one of their addition salts with an acid as oxidation dye precursor.

Abstract: Oxidation dye composition for keratinous fibers comprising a para-aminophenol, a meta-aminophenol and a meta-phenylenediamine and dyeing process using such a composition.The invention relates to a dyeing composition for keratinous fibers and in particular for human keratinous fibers such as hair, comprising, in a suitable medium for dyeing, at least one oxidation dye precursor chosen from 3-methyl-para-aminophenol, 2-methyl-para-aminophenol and 2-hydroxymethyl-para-aminophenol, and their addition salts with an acid; at least one coupling agent chosen from the 2-methyl-5-aminophenols of formula (I): ##STR1## where R denotes hydrogen, methyl, ethyl, .beta.-hydroxyethyl or .gamma.-hydroxypropyl, and their addition salts with an acid; and, as additional coupling agent, at least one meta-phenylenediamine or one of its addition salts with an acid. The invention also relates to a dyeing process implementing development by an oxidizing agent.

Abstract: Processes for the dyeing of keratinous fibers with compositions which contain 4-hydroxy- or 4-aminobenzimidazole or their derivatives corresponding to the formula (I): ##STR1## in which: R.sub.1 and R.sub.2 represent hydrogen or alkyl, one at least of the substituents being equal to hydrogen,R.sub.3 denotes OH or NH.sub.2,as coupler for dyeing keratinous fibers, in particular hair, in the presence of a p-phenylenediamine, the ratio between the p-phenylenediamine and the coupler of formula (I) being greater than or equal to 1.2.

Abstract: Process for dyeing keratinous fibres, especially human keratinous fibres such as the hair, characterised in that a composition containing, in a medium suitable for dyeing, at least 2,4-diamino-1,3-dimethoxybenzene as a coupler;an oxidation dye precursor; andan oxidising agent; is applied to these fibres,the pH of the composition applied to the fibres being less than 7.

Abstract: Process for dyeing keratinous fibres, in particular human keratinous fibres such as hair, characterized in that there is applied to these fibres a composition containing, in a suitable dyeing mixture, at least one indole-based coupler, of the formula: ##STR1## in which R.sub.1 designates a hydrogen atom or a C.sub.1 -C.sub.4 alkyl radical; R.sub.2 and R.sub.3, which may be identical or different, designate a hydrogen atom, a C.sub.1 -C.sub.4 lower alkyl radical, a carboxyl radical or an alkoxycarbonyl radical; X designates a hydrogen atom, a C.sub.1 -C.sub.4 lower alkyl radical, a C.sub.1 -C.sub.18 alkoxy radical, a halogen atom, a C.sub.2 -C.sub.20 acyloxy radical or an acetylamino group; the OH group occupying the 6- or 7- positions of the aromatic ring; as well as the salts of these compounds;one oxidation dye precursor;one oxidising agent;the pH of the composition applied to the fibres being less than 7.