An agent for coloring keratinic fibers included in a cosmetic carrier includes at least one cationic acrylic acid ester copolymer including at least one structural unit of the general formula (I), at least one structural unit of the general formula (II), and at least one structural unit of the general formula (III), in which R1, R2, R3, R4, R6 mutually independently denote a hydrogen atom or a C1 to C6 alkyl group, R5, R5′, R5″ mutually independently denote a C1 to C20 alkyl group, a C2 to C6 alkenyl group, or a C2 to C6 hydroxyalkyl group, R7 denotes a C1 to C6 alkyl group, a C2 to C6 hydroxyalkyl group, or a C2 to C6 polyhydroxyalkyl group, n denotes an integer from 1 to 50,000, m denotes an integer from 2 to 6, X− denotes a physiologically acceptable anion. The agent further includes at least one color-changing compound.
