US Patent 7172633 Lightening dye composition comprising at least one cationic direct dye containing mixed chromophores

The present invention relates to a lightening dye composition comprising, in a suitable dyeing medium, an oxidizing agent, an alkaline agent in an amount such that the pH of the composition is greater than 7, and a mixed cationic dye comprising several chromophores linked together via a linker, at least two of the chromophores being different, the chromophores having an absorbance of between 400 and 800 nm. The invention makes it possible to obtain particularly fast colorations.