Cosmetic composition, useful for dyeing and lightening keratin fibers, comprises direct dye having disulfide, thiol or protected thiol group, organic polymer thickener, nonionic surfactant, alkali agent, and reducing agent
Cosmetic composition (I) comprises: at least one direct dye having a disulfide, thiol or protected thiol functional group (A) or its salt of organic or inorganic acid, optical isomer, geometrical isomer, tautomer or solvate such as hydrate； an organic polymer thickener； a nonionic surfactant； an alkali agent comprising an amino group； and a reducing agent. Cosmetic composition (I) comprises: at least one direct dye having a disulfide, thiol or protected thiol functional group of formula (A-(X) p-C s a t-S-U1) (A) or its salt of organic or inorganic acid, optical isomer, geometrical isomer, tautomer or solvate such as hydrate； at least one organic polymer thickener； at least one nonionic surfactant； at least one alkali agent comprising at least one amino group； and at least one reducing agent. U1 : (-S-C1 s a t-(X1) p 1-A1) or Y1； A, A1 : radical containing at least one quaternized cationic chromophore or at least one chromophore carrying a cationic quaternized or quatemisable group； y1 : protecting thiol group； X, X1 : 1-30C divalent hydrocarbon chain (optionally saturated, interrupted and/or terminated bed one or two of its ends by one or more divalent groups comprising -N(R)-, -N +>；(R)(R)-, -O-, -SO 2- or (hetero)cyclic non-aromatic ring optionally saturated or non-condensed with one or more heteroatoms (optionally substituted))； p, p1 : 0 or 1, preferably 1； and C s a t, C1 s a t : 1-18C alkyl (optionally substituted or cyclic), at least one organic polymer thickener, at least one non-ionic surfactant, at least one alkali agent comprising at least an amino group or at least one reducing agent. Independent claims are included for: (1) dyeing keratin fibers, preferably dark keratin fibers, comprising applying the cosmetic composition and optionally at least one chemical oxidizing agent to the keratin fibers, where the ingredients are applied to the fiber either separately or in a combined manner； (2) dyeing and lightening the dark keratin fibers, comprising appl
