Alkali-clearable disperse dyeing of poly(ethyleneterephthalate) with azohydroxypyridone dyes containing a fluorosulfonyl group

Dyeing properties of a series of alkali-clearable azohydroxypyridone disperse dyes containing a fluorosulfonyl group on poly(ethyleneterephthalate) have been investigated. The dyes showed reasonably good build-up properties and had a yellow shade on PET. The dyes exhibited excellent fastness properties on PET fabric, irrespective of the clearing method. Specially, the azohydroxypyridone dyes containing a nitro group in place of the fluorosulfonyl group in the para position to azo group were synthesised in order to compare their dyeing and fastness properties on poly(ethyleneterephthalate) with those of fluorosulfonyl-substituted analogues.