Use of polycationic azo compounds for dyeing keratinous fibres

摘要

Using a polycationic compound (I) as a direct dye in tinctorial composition (II) for keratinous fibers (particularly human keratinous fibers such as hair) or for the manufacture of the composition, is new. Use of a polycationic compound (I) of formula A-L-B as a direct dye in tinctorial composition (II) for keratinous fibers (particularly human keratinous fibers such as hair) or for the manufacture of (II). A and B = coloring group of arylazoimidazolium type; and L = bonding arm comprising at least a cationic group (C'). Independent claims are also included for: (1) (II) comprising (I), an oxidation base and/or at least an additional direct dye; and (2) dyeing keratinous fibers comprising applying (II) on the keratinous fibers and allowing to remain.