ABSTRACT
Abstract: Polyester is nonionic, hydrophobic and thermoplastic in nature. Its highly compact structure permits efficient dyeing only at high temperature with disperse dyes, preferably in closed machines. Carriers swell up polyester at boil to facilitate dyeing in open baths at boil forming poor wash fast, very light shades only. Dispersing agent holds dye in dispersion but addition in excess reduces dye uptake by enhancing solubility of dye, when excess dispersing agent helps to reduce barré in textured fibre. Complications associated with dyeing at high temperature have led to development of anionic as well as carrier free dyeable polyester.
