Sulphur dyes on nylon 6,6. Part 3. Preliminary studies of the nature of dye–fibre interaction

Four different types of nylon 6,6 fabric (deep-dyeable, standard-dyeable, cationic-dyeable and acetylated variants) were dyed using solubilised sulphur dyes as well as sulphur dyes. The colour strength of the dyeings on the four different types of nylon 6,6 fabric was little influenced by either the AEG content of the fibre or the nature of the polymer from which the substrates had been made. The finding that the colour of dyeings on each of the four types of fibre was not dissimilar also implied that the interactions between both solubilised sulphur dyes as well as sulphur dyes and the different fabrics was little influenced by the nature of the polymer. It is postulated that the adsorption of both solubilised sulphur dyes and sulphur dyes onto nylon 6,6 is predominantly non-site-specific and, therefore, that dye–fibre substantivity occurs principally through H-bonding, dispersion forces and polar van der Waals' forces of interaction.