Reactive dyes and preparation methods thereof

Abstract

Disclosed are reactive dyes and preparation methods thereof. The reactive dye may be prepared using heterocyclic primary amine as a diazo component, 4,4′-diamino-2,2′-stilbenedisulfonic acid, s-triazine, or ethylenediamine as a bridging group, and a dimonochlortriazine group as an active group. The color-changing compound is covalently bonded into the fiber chemical structure by nucleophilic substitution reaction between monochlorotriazine and the hydroxyl group in a textile structure, and the size of the conjugated system and the range of electron delocalization of the dye are changed by a reversible isomerization reaction of the hydroxyl group adjacent to the diazo group and the diazo group under different pH regulations. Moreover, the dye has a double color changing structure, which improves the capability of the dye combined with —H/—OH. The pH value range that can cause color changes in the dye is effectively expanded to include weak alkali, weak acid or even neutral conditions.

Dependencies are inferred from the claim text.