Disazo direct dyes containing cyclic amido, keto and amino groups

Abstract

Derived from diamines containing amino, carbonyl, carbamide and urea groups between biphenyl rings, a series of disazo dyes have been synthesised. Similar dyes have been obtained from diamines containing cyclic carbazole, fluorenone and phenanthridone systems. The effect of the molecular structure of the dyes on their colour and affinity for cellulose fibres, compared with the properties of corresponding benzidine dyes, has been studied. It has been found that 3,8-diaminophenanthridone derivatives show the most favourable properties. They are derivatives of benzidine dyes, containing additionally a cyclic amide group.