Patent ID: 7651538

Claim:
A hair dye composition comprising (1) an azo dye represented by the following formula (1): (wherein R 1 , R 2 , R 3 , and R 4 each independently represents a hydrogen atom, an aliphatic hydrocarbon group, an aryl group, a halogen atom, an acyl group, a cyano group, an acylamino group, an aliphatic oxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, an aliphatic sulfonyl group, an arylsulfonyl group, a sulfamoyl group, an aliphatic oxycarbonylamino group, an aryloxycarbonylamino group, a sulfo group, a carboxy group, a carbamoylamino group, a sulfamoylamino group or an aliphatic or aromatic sulfonylamino group, wherein R 1 and R 2 , and/or R 3 and R 4 may be coupled to form a 5- or 6-membered aromatic or non-aromatic ring; X represents a carbon atom or a nitrogen atom with the proviso that when X represents a carbon atom, n stands for 1, and when X represents a nitrogen atom, n stands for 0; A 1 , A 2 , A 3 and A 4 each independently represents a nitrogen atom or represents a carbon atom substituted by Y or having a hydrogen atom, with the proviso that at least one of A 1 , A 2 , A 3 and A 4 is a nitrogen atom; and Y represents a substituent with the proviso that m stands for an integer from 0 to 3), or a salt thereof, and (2) an oxidizing agent.