| abstract |
The subject of the present invention is symmetrical diazo cationic compounds of formula (I) below, their resonant forms, as well as their addition salts with an acid and their solvates: in which W 1 identical represent a halogen atom, a group -NR 4 -Ph-NR 5 R 6 , -NR 4 -Ph-OR 7 , -O-Ph-OR 7 , -O-Ph-NR 5 R 6 ; The cationic linking arm linking the two identical azo chromophores represents a C 2 -C 40 alkyl radical carrying at least one cationic charge, optionally substituted and / or optionally interrupted by one or more (hetero) saturated or unsaturated rings; the linking arm L not including azo bond, nitro, nitroso, peroxo.n n n The invention furthermore relates to dyeing compositions comprising, in a medium which is suitable for dyeing keratinous fibers, such compounds as a direct dye, as well as a process for dyeing keratinous fibers using this composition and a device for several dyeing compositions. compartments. |