AGENT FOR DECOLOURING OF COLOURED KERATIN FIBRES Russian patent published in 2020 - IPC A61K8/00 A61K8/41 A61K8/23 A61K8/46 A61K8/34 A61Q5/08 A61Q5/12 

FIELD: cosmetic industry.

SUBSTANCE: invention relates to cosmetic industry and can be used for decolouration (reducing decolouration) of coloured keratin fibres coloured with oxidation and/or direct dyes, such as human hair. Described is an agent for restorative decolouration of keratin fibres coloured with oxidation and/or direct dyes, containing a combination of about 0.5 to about 10.0 wt. % of formamidine sulphinic acid or its cosmetically acceptable salt, from about 0.5 to about 15.0 wt. % of hydroxymethane sulphinic acid or its cosmetically acceptable salt and from about 0.5 to about 25.0 wt. % of polyvinylpyrrolidone. Essential property of the agent under the invention is shown to be effective in neutral medium at pH 6.5–7.5, in which reaction of reducing destruction of disulphide bridges of keratin fibres proceeds very slowly or even does not proceed at all.

EFFECT: technical result is solving the problem of reducing strength characteristics, mechanical strength of keratin fibres, such as hair, the disclosed combination of components for restorative decolouration of keratin fibres coloured with oxidation and/or direct dyes, provides end of dye reduction reaction substantially faster than using each non-universal agent separately.

9 cl, 9 tbl