Reactive dyes for wool which incorporate a water-stable bisulphate-isocyanate adduct as the ‘masked’ reactive group can be applied in the form of levelling acid dyes. High fastness to washing on wool can subsequently be attained by fixing the dye with alkali or steam treatments

The preparation of azo dyes from 2,6-diaminobisthiazolo[4,5-b,5′,4′-e]pyridine and the dyeing properties of these disperse dyes are reported