Process for dyeing human hair with diazo salts and coupling components
AssigneeHenkel Kommanditgesellschaft auf Aktien
InventorsArthur Buhler, Alfred Fasciati, Walter Hungerbuhler
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Abstract
Described is a process for dyeing keratin-containing material with developing dyes by applying diazo salts and coupling components successively, in any desired sequence, to the material to be dyed, and coupling them with each other, characterized in that there are used as coupling components specific derivatives of hydroxypyridine or pyridone.
Claims13
A process for dyeing human hair with developing dyes which comprises applying to said hair, at temperatures from about 15.degree. C. to 40.degree. C., an effective amount of aqueous solutions of diazo salts and coupling components successively, in any desired sequence, and coupling said diazo salts and coupling components with each other, wherein the coupling component is of the formula (1) or (2) ##STR33## wherein R.sub.1 is hydrogen or a monovalent organic radical,
- R.sub.2 is cyano, aminocarbonyl or an alkyl group substituted by a carboxylic acid group or sulphonic acid group,
- R.sub.3 is an alkyl group which has up to five carbon atoms and which is optionally substituted by a carboxylic acid group or sulphonic acid group, or a phenyl group which can optionally carry in the p-position a further similar pyridone group,
- X is the OH or NH.sub.2 group, and
- Z is a hydrogen or halogen atom, and the concentration of said solutions is between 0.1 and 10% by weight of said diazo salts and coupling components and said diazo salts and coupling components are present in the molar range of about 2:1 to 1:2.
Dependencies are inferred from the claim text.