The chlorination of wool in order to improve its luster, produce a non-felting
finish and increase its substantivity in the production of printed
fabric, is no simple operation. This process influences the macromolecular
fiber composition and the structure of the wool fiber. Chlorination breaks
down or completely removes the scale layer. A complete removal occurs
particularly if the fabric is chlorinated in the acid pH range - the scale layer is
then virtually separated. Through chlorination, wool becomes more lustrous
(silk wool), displays more or less strong yellowing phenomena and can occasionally
lose its wear resistance. However, the affinity of chlorinated wool
for dyes as well as the wettability are increased, which is essential for wool
printing.