Studies on n-Butanol Assisted Dyeing of Lanasol (Acid Reactive) Dyes on Nylon 66

Four Lanasol (acid reactive) dyes were applied on nylon 66 from aqueous and from n-butanol assisted aqueous dyebaths. The n-butanol did not change the hue of the shades in solution or on the substrate to any noticeable extent; n-butanol caused disaggregation of the dyes in solution and also on the substrate. Its presence in the dyebath increased diffusion rate of the dyes in the substrate and also the lightfastness of the dyeings. The increase in lightfastness can be explained as due to greater pen etration of the dyes in the substrate.