Carrier dyeing of polyester fibre with some disperse azo dyes

This paper reports the effects of phenol, as a carrier, on the kinetics and thermodynamics of the dyeing of polyester fibre with some substituted benzothiazolyl azo dyes. The dyeing rate constants, the thermodynamic affinity and the apparent diffusion coefficients depend on the carrier concentration and on the dye structure, i.e. the presence of hydroxy groups in the N,N-diethylamino moiety of the coupler and of the phenyl ring between the thiazole and azo group. The results indicate the phenol does not behave by plasticizing the fibre, but it mainly acts as dispersant of the dye in the dyebath.