Alkali Damage Research Articles

Relation Between Dyeing Properties of Wool and Modifications of the Fiber

Dye rates were measured for unsteamed and steamed solvent-extracted wool. These meas urements indicate that the dye rates for wool that has not been alkali-damaged, or wool in which the alkali damage has been restricted to the fiber surface, are not influenced by steaming. The dyeing time for wool treated with an aqueous alkaline solution is increased considerably by steaming. This would indicate that the effect of steaming is due to modifications in the bulk of the wool fiber.

Effects of Concentrated Aqueous and certain Non-aqueous Solutions of Alkali upon Wool

CHEMISTS are well aware that wool is readily attacked by alkaline reagents. These disrupt the disulphide groups of the cystine contained in the polypeptide chains, thus weakening the fibre structure. The woollen manufacturer also recognizes that wool is susceptible to attack by alkali, as the term ‘alkali damage’ indicates. This damage frequently results from inefficient scouring which afterwards causes the wool to dye unevenly.