Lipid Role in Wool Dyeing

The textile industry uses different fibers obtained from various animals, of which the wool from domesticated sheep Ovis aries is commercially the most important. Dyeing is one of the most important finishing procedures of wool processing. It almost invariably involves absorption of water-soluble colorants from aqueous solutions by the fibers. Diffusion is the process by which the colorant molecules penetrate the interior of the fibers. Earlier workers studying the dye uptake of dyes by wool were mainly interested in the thermodynamics of the process, treating the wool fiber as a cylinder of uniform composition. Over the last decades there has been growing recognition of the importance of the diverse morphological structure of wool in determining its dyeing behavior (Rippon, 1992). Therefore a short wool structure description will be followed by a review of the role of this structure in wool dyeing. The importance of the non-keratinous components of the fiber, specially the study of lipids present in the cell membrane complex prone us to emphasize in the lipid depleted wool, the modification of many properties and its behavior in the dyeing process. Besides the study of the mechanism of liposomes (made up with phospholipids) on wool dyeing could also help to elucidate the lipid role in wool dyeing.