Covalent fixation of hydroxyethyl sulphone dye on cotton by the use of crosslinking agent via a pad‐batch process

A trifunctional reactive crosslinker, 2,4,6‐tri{ρ‐[(2′‐sulphatoethyl)sulphonyl]phenylamino}‐1,3,5‐triazine (Tri‐SES) was synthesised and co‐applied with hydrolysed Cl Reactive Black 5 (hydroxyethyl sulphone dye) to cotton to achieve dye‐fibre covalent bonding via a cold pad‐batch process. Several factors affecting the dye—crosslinker‐cotton covalent fixation reactions have been studied and are discussed in this paper. It was found that the dye fixation was strongly dependent on the alkali type and concentration. Very high fixation values (ca. 97%) were obtained under the optimised conditions.