Use of imidazo-(1,2,a)-pyridine-2(3H)-one cpd. or salt - as coupler, with developer in oxidn. dyeing of hair

摘要

Imidazo(1,2a)pyridine-2(3H)-ones of formula (I) or their salts, are used as couplers, with the usual developers, to give oxidn. dyeings. In (I), R1, R2, R3, R4 = H or 1-4C alkyl. Pref. one of the R gps. is 1-4C alkyl, esp. Me, and the others are H. Also pref. a hair dye contains an oxidn. dye precursor, with (I) as coupler and the usual developer, esp. p-phenylene diamine and/or 2,4,5,6-tetraaminopyrimidine or salts. The dye esp. contains a carrier which is a gel contg. 1-20 wt.% of a soap or an oil-in-water emulsion with 1-25 wt.% of fatty component and 0.5-30% of an anionic, nonionic or ampholytic tenside as emulsifier, and 0.05-10 mmols (I) 100 g of hair dye, as oxidn. dye precursor. ADVANTAGE - Uniform hair colours are obtd.(5pp Dwg.No.0/0)