Patent ID: 7285137

Claim:
A composition for dyeing keratinous fibers comprising, in an appropriate dyeing medium, at least one oxidation base chosen from diamino-N,N-dihydropyrazolone derivatives of formula (I) and addition salts and solvates thereof: wherein: R 1 , R 2 , R 3 and R 4, which are identical or different, are each chosen from: linear and branched C 1 –C 6 alkyl radicals optionally substituted with at least one radical chosen from a radical OR 5 , a radical NR 6 R 7 , a carboxyl radical, a sulphonic radical, a carboxamido radical CONR 6 R 7 , a sulphonamido radical SO 2 NR 6 R 7 , heteroaryl radicals, and aryl radicals optionally substituted with at least one radical chosen from (C 1 –C 4 )alkyl, hydroxyl, C 1 –C 2 alkoxy, amino, and (di)alkyl(C 1 –C 2 )amino radicals; aryl radicals optionally substituted with at least one radical chosen from (C 1 –C 4 )alkyl, hydroxyl, C 1 –C 2 alkoxy, amino, and (di)alkyl(C 1 –C 2 )amino radicals; and 5- and 6-membered heteroaryl radicals optionally substituted with at least one radical chosen from (C 1 –C 4 )alkyl and (C 1 –C 2 )alkoxy radicals; or, alternatively, R 3 and R 4 are each a hydrogen atom; R 5 , R 6 and R 7 , which are identical or different, are each chosen from a hydrogen atom; linear and branched C 1 –C 4 alkyl radicals optionally substituted with at least one radical chosen from a hydroxyl radical, C 1 –C 2 alkoxy radicals, a carboxamido radical CONR 8 R 9 , a sulphonyl radical SO 2 R 8 , and aryl radicals optionally substituted with at least one radical chosen from (C 1 –C 4 )alkyl, hydroxyl, C 1 –C 2 alkoxy, amino, and (di)alkyl(C 1 –C 2 )amino radicals; and aryl radicals optionally substituted with at least one radical chosen from (C 1 –C 4 )alkyl, hydroxyl, C 1 –C 2 alkoxy, amino, and (di)alkyl(C 1 –C 2 )amino radicals; or, alternatively, R 6 and R 7 , which are identical or different, are each chosen from a carboxamido radical CONR 8 R 9 and a sulphonyl radical SO 2 R 8 ; R 8 and R 9 , which are identical or different, are each chosen from a hydrogen atom; and linear and branched C 1 –C 4 alkyl radicals optionally substituted with at least one radical chosen from hydroxyl and C 1 –C 2 alkoxy radicals; wherein at least one of R 1 and R 2 , and R 3 and R 4, may form, together with the nitrogen atoms to which they are attached, a heterocycle chosen from saturated and unsaturated 5- to 7-membered heterocycles optionally substituted with at least one entity chosen from halogen atoms and amino, (di)alkyl(C 1 –C 4 )amino, hydroxyl, carboxyl carboxamido and (C 1 –C 2 )alkoxy radicals, and C 1 –C 4 alkyl radicals optionally substituted with at least one radical chosen from hydroxyl, amino, (di)alkylamino, alkoxy, carboxyl and sulphonyl radicals; and R 3 and R 4 may also form, together with the nitrogen atom to which they are attached, a 5- or 7-membered heterocycle whose carbon atoms are optionally replaced with at least one optionally substituted atom chosen from optionally substituted oxygen and nitrogen atoms.