Patent ID: 8608811

Claim:
A process for oxidative dyeing keratin fibers comprising: mixing compositions A and B to form a mixture, wherein composition A comprises at least one oxidative dye precursor and, optionally, at least one coupling agent and, optionally, at least one direct dye in a cosmetically acceptable medium, and further wherein composition B comprises at least one oxidizing agent in a cosmetically acceptable medium; and applying the mixture onto the keratin fibers and processing for 1 to 45 min at a temperature range of 20 to 45° C. and rinsing the mixture off from the keratin fibers, wherein at least one of the two compositions A and B comprises a cross linked copolymer of vinylpyrrolidone, vinylimidazol, 3-methyl-1-vinylimidazolium and methacrylic acid.