| abstract |
Disclosed herein are a composition for dyeing keratinous fibers, for example, human keratinous fibers such as hair, comprising at least one oxidation base chosen from diamino-N,N-dihydropyrazolone derivative and a method using the composition. Further disclosed herein are amino-N,N-dihydropyrazolone derivatives and the addition salts thereof and diamino-N,N-dihydropyrazolone derivatives and the addition salts thereof, as well as the methods for preparing these compounds. |