Compositions for dyeing keratin fibers

A cosmetic agent for coloring keratin-containing fibers, comprising, in a cosmetic carrier:

• (a) at least one star polymer comprising a structural fragment acting as a center, and at least three groups radially bound to this center, wherein these groups:
• (i) each have at least one polyether structural unit comprising a polyoxyalkylene chain consisting of either ethylene oxide units or both ethylene oxide and propylene oxide units, wherein the polyoxyalkylene chain has a maximum proportion of 50 wt. % of propylene oxide units, relative to the weight of the polyoxyalkylene chain, and
• (ii) each have at least one residue comprising:
• at least one *—Si(OR)x(R′)3-x group, in which R and R′, independently of one another, denote a (C1 to C4) alkyl group, x denotes 1, 2 or 3;
• at least one anionic group;
• at least one quaternized nitrogen atom;
• or
• combinations thereof,
• and
• (b) at least one coloring compound to color the keratin-containing fibers, in which the at least one coloring compound comprises at least one of:
• (i) an oxidative dye precursor of a developer component type;
• (ii) a substantive dye;
• and
• (iii) a precursor of a nature-analogous dye;
• in which the change in color of the keratin fibers that results from the treatment of the keratin fibers with the agent persists through the first shampoo of the keratin fibers following treatment with the agent.

A cosmetic method, comprising:

• (A) applying to keratin-containing fibers a cosmetic agent comprising at least one coloring compound to color the keratin-containing fibers, and at least one star polymer comprising a structural fragment acting as a center and at least three groups radially bound to this center, wherein these groups:
• (i) each have at least one polyether structural unit comprising a polyoxyalkylene chain consisting of either ethylene oxide units or both ethylene oxide and propylene oxide units, wherein the polyoxyalkylene chain has a maximum proportion of 50 wt. % of propylene oxide units, relative to the weight of the polyoxyalkylene chain, and
• (ii) each have at least one residue comprising:
• at least one *—Si(OR)x(R′)3-x group, in which R and R′, independently of one another, denote a (C1 to C4) alkyl group, x denotes 1, 2 or 3;
• at least one anionic group;
• at least one quaternized nitrogen atom;
• or
• combinations thereof;
• (B) allowing the cosmetic agent to act on keratin-containing fibers;
• and
• (C) after a contact time, rinsing the cosmetic agent from the keratin-containing fibers.