摘要 |
The present disclosure relates to symmetrical cationic diazo compounds of formula (I) below, their resonance forms, and also their acid addition salts and their solvates: wherein W<SUB>1 </SUB>radicals, which are identical, are chosen from a halogen atom, or an -NR<SUB>4</SUB>-Ph-NR<SUB>5</SUB>R<SUB>6</SUB>, -NR<SUB>4</SUB>-Ph-OR<SUB>7</SUB>, -O-Ph-OR<SUB>7 </SUB>or -O-Ph-NR<SUB>5</SUB>R<SUB>6 </SUB>group or else an -NR<SUB>5</SUB>R<SUB>6 </SUB>or -OR<SUB>7 </SUB>group with certain provisos; L, a non-cationic linker connecting the two identical azo chromophores, is chosen from a covalent bond; an optionally substituted C<SUB>1</SUB>-C<SUB>40 </SUB>alkyl radical optionally interrupted by a (hetero)cycle, the alkyl radical being optionally interrupted by at least one heteroatom or group comprising at least one heteroatom or an optionally substituted phenyl radical. The disclosure further relates to dyeing compositions comprising such compounds as a direct dye in a medium appropriate for the dyeing of keratin fibers, and also to a method of coloring keratin fibers that employs this composition, and a device comprising a plurality of compartments. |