METHOD FOR DYEING KERATIN FIBRES USING CATIONIC STYRYL DISULPHIDE DYES, AND COMPOSITION INCLUDING SAID DYES Russian patent published in 2019 - IPC A61Q5/10 A61Q5/08 A61K8/49 C09B23/14 C07D401/12 

FIELD: cosmetology.

SUBSTANCE: invention relates to a method for dyeing and/or lightening keratin fibres using novel cationic disulphide dyes, to a cosmetic composition containing such dyes, and to a multi-compartment device containing such dyes. Method includes applying to keratin fibre at least one cationic styryl disulphide dye of formula (II) or (III), where R₁, R₂, R₃, R'₁, R'₂, R'₃ have values given in the description.

EFFECT: invention makes it possible to dye keratin fibres with or without use an oxidising agent while ensuring long-lasting colour with increased colour intensity, colour selectivity between the root and the tip of keratin fibre (human hair) and the expansion of the range of known disulphide dyes with said colour properties.

13 cl, 3 tbl, 125 ex