WATERRSOLUBLE AZO DYES

Water-soluble azo dyes which in the form of the free acid conform to the formula I where R is hydrogen, optionally substituted alkyl or arylsulphonyl and the other substituents are as defined in Claim 1, are obtained by reacting appropriate diazotised amines with coupling components of the formula C6H3(R5)(R6)(OH) and then optionally alkylating or arylsulphonating. The new dyes are suitable for dyeing and printing natural and synthetic amido-containing fibre materials, for example those comprising wool, silk and polyamide, such as polyepsilon -caprolactam or the reaction product of hexamethylenediamine with adipic acid. The dyeings obtained, in particular those on polyamide materials, are notable for good fastness properties, in particular for good wet fastness properties and good light fastness properties. Similarly, the neutral-dyeing capacity and the compatibility with other suitable dyes for this material is in general good. The dyes of the formula (I) are normally used for dyeing either in the form of the free acid or in the form of an alkali metal or ammonium salt.