11.02.07
Patent No. US 7,285,137 B2:
A composition for dyeing keratinous fibers comprising, in an appropriate dyeing medium, at least one oxidation base chosen from diamino-N,N-dihydropyrazolone derivatives has been patented by L’Oréal Paris, France.
A composition for dyeing keratinous fibers comprising, in an appropriate dyeing medium, at least one oxidation base chosen from diamino-N,N-dihydropyrazolone derivatives has been patented by L’Oréal Paris, France.