Multi-Tonal One-Step Dyeing Patented by Henkel

US Patent No. 9,918,910 B2; Henkel AG & Co. KGaA has patented a method for the oxidative dyeing of keratinic fibers that comprises the following steps in the indicated sequence:
a) applying a cosmetic agent (M1) to the keratinic fibers,
b) allowing agent (M1) to act on the keratinic fibers for a time period of 30 seconds to 40 minutes at a temperature of at least 25°C.,
c) applying a cosmetic agent (M2) to the keratinic fibers treated with cosmetic agent (M1),
d) allowing cosmetic agents (M1) and (M2) to act on the keratinic fibers for a time period of 1 to 70 minutes, and
e) rinsing out of cosmetic agents (M1) and (M2).


Cosmetic agent (M1) includes at least one oxidation dye precursor of the developer type (M1-1), at least one oxidation dye precursor of the coupler type (M1-2), at least one direct dye (M1-3), and at least one surfactant (M1-4).Cosmetic agent (M2) includes at least one oxidation dye precursor (M2-1) and at least one oxidizing agent (M2-2).