Azo dyes from 2-amino-3-nitro-5-acylthiophene

Abstract

Disclosed are novel azo dyes containing a substituted thiophene diazo moiety which produces bright blue shades on polyester and also have good affinity, dyeability and other properties on cellulose esters. The dyes have the formula ##STR1## wherein R is selected from alkyl, phenyl and phenyl substituted with 1-3 of alkyl, alkoxy, halogen or nitro; R.sub.1 and R.sub.2 are each alkyl or one of which is also selected from hydrogen; R.sub.3 is selected from hydrogen, cycloalkyl, alkyl, alkoxy, alkylamino, phenyl, phenyl substituted as for R above, and alkyl substituted with 1-3 of hydroxy, alkoxy, acyloxy, halogen, phenyl, phenoxy or cyclohexyl; X is hydrogen, alkyl, or alkoxy; and wherein each alkyl and alkoxy moiety is straight or branched and contains from 1-8 carbons.

Dependencies are inferred from the claim text.