DYEING PROPERTIES OF BASIC AZO-DYES FROM 2-AMINO THIADIAZOLE

Some new basic azo-dyes derived from thiadiazole were synthesized to evaluate the dyeing parameters on polyester fibre (PET) for optimizing the dyeing process. The kinetics of dyeing were performed at various temperatures (80-degrees, 90-degrees and 100-degrees-C) in the absence and in the presence of phenol, benzoic acid and salicylic acid as carriers. Thermodynamic affinities were also measured. The dyeing rate constants increase on increasing the concentration of carrier, while low affinity values were observed for the dyes bearing hydroxyl groups, owing to increased solubility of the dye in the dyebath. This behaviour is less evident in the dyes bearing a methyl group in the thiadiazole ring. The dyes show good fastness to light, perspiration and dry cleaning.