PROCESS FOR OXIDATIVE COLOURING KERATIN FIBRES

摘要

The present invention concerns a process for oxidative coloring keratin fibers especially human hair wherein a pretreatment is applied onto hair prior to application of oxidative colouring agent. Accordingly, present invention is a process for oxidative dyeing of keratin fibers especially human hair wherein an aqueous composition comprising at least one inorganic salt catalyzing and/or effecting the oxidative colour development reaction from oxidative dye precursors is applied onto wet or dry hair and optionally rinsed off, and subsequently an aqueous composition comprising at least one oxidative dye precursor, optionally at least one coupling agent and at least one oxidizing agent is applied onto hair and after processing of 5 to 45 min with or without use of heat, preferably at a temperature range between 20 and 45° C., rinsed off from hair.