The Modification of the Surface Diffusion Barrier of Wool

The covalently bound fatty acid monolayer on the surface of wool fibres acts as a hydrophobic barrier which can be removed by alcoholic alkaline or chlorine treatments. Aqueous treatments have been investigated for the removal of the covalently bound fatty acid layer. Base/cationic detergent treatments were found to be the most effective aqueous treatments, removing up to 65 % of the surface bound fatty acid. When more than 20 % of the covalently bound fatty acid was removed, wetting times were found to be significantly reduced. The time of dyeing for C.I. Acid Red 1 was reduced significantly following sodium carbonate/cetyl trimethylammonium hydroxide treatments. The modification of surface bound fatty acids was assessed by monitoring the amount of 18-methyleicosanoic acid remaining bound to the fibre following each treatment