Acid azo dyes containing heterocyclic couplers

Abstract

Disclosed are novel acid azo dyes containing a sulfonated, sulfated or thiosulfated organothiothiadiazole azo moiety and a heterocyclic coupler which may be substituted. The dyes produce reddish-yellow to orange shades on, for example, hydrophobic textile fiber including polyesters, polyamides, and cellulose esters and have excellent fastness properties including lightfastness, stability to heat, washfastness and resistance to sublimation, and dye at unusually low energy levels. The dyes have the general formulae: ##STR1## wherein D is the aforesaid organothiothiadiazole moiety; R.sup.3 is selected from hydrogen, lower alkyl, and aryl; R.sub.4 is selected from H, lower alkyl, CH.sub.2 aryl, aryl, and lower alkyl substituted with cyano, carbamoyl or acylamino; Ar is a wide variety of carbocyclic radicals; and Z represents the atoms necessary to complete a five or six membered ring.

Dependencies are inferred from the claim text.