According to L'Oréal inventors, there is a market need for hair dyeing processes that produce sufficiently powerful and persistent color using direct dyes and/or self-oxidizing dyes. Of particular interest are organic dyes and pigments from natural extracts.
Consumers also want products that are less aggressive to their hair or require lower dye levels, even in the absence of a chemical oxidizing agent. In addition, the color must withstand external agents including light, weather, shampooing or sweat.
A new invention based on titanium salts claims to meet these needs while achieving homogenous application, i.e., from the hair root to tip.
Natural hair dye
WIPO Patent Application WO/2016/198666
Publication date: Dec. 15, 2016
Disclosed in this invention is a process for dyeing keratin fibers with cosmetic compositions containing:
a) one or more titanium salts, particularly in the oxidation state of 2, 3 or 4 [Ti(ll), Ti(lll) or Ti(IV)], preferably Ti(IV);
b) optionally one or more carboxylic acid(s) or a salt thereof; and
c) one or more dyes chosen from cationic, anionic or neutral natural dyes or synthetic direct dyes and self-oxidizing dyes, particularly neutral natural dyes, preferably chosen from ortho-diphenols.
Without chemical oxidizing agents, a), b) and c) are applied to hair fibers together or separately for the desired results.