Wash-and-Wear Finishing of Silk Fabrics with a Water-Soluble Polyurethane

A water-soluble bifunctional polyurethane WPU200 is prepared and used for wash-and- wear finishing of silk fabrics. The wet resiliency of the finished silks greatly improves, and dry resiliency drops a little. Anionic and nonionic softeners, which can improve the dry crease recovery angle and handle of finished silk fabrics, can be used in a single bath with WPU200. Factors that have a great influence on the resiliency of the finished fabrics include WPU200 concentration, curing temperature and time, and pH of the finishing bath. All these factors have been optimized. Changes in the physical properties of the finished silk fabrics are reported, such as breaking strength, elongation, moisture regain, whiteness, and stiffness. Finished silk fabrics have good laundry durability after twenty washing cycles.