INTERACTION OF VINYLSULPHONE REACTIVE DYES WITH CELLULOSIC FABRICS .2. DYE ASSOCIATIONS AND DYE-SURFACTANT INTERACTIONS

The ability of reactive dye molecules (Cl Reactive Red 180 and Cl Reac tive Yellow 23) to undergo self-association and to associate with diff erent surfactants has been examined spectrophotometrically. The stabil ity constants K(DS) of the dye-surfactant complexes were calculated at dye:surfactant ratios varying from 1:0 to 1:10 and for different surf actant types (anionic, zwitterionic, nonionic and cationic). Dye uptak e on viscose fibre observed for a dye:surfactant molar ratio of 1:0.5 was found to be related to K(DS) values.