GB269605A - Improvements in or relating to the treatment of products or goods of or containing cellulose acetate - Google Patents

Abstract

269,605. Clavel, R. Nov. 10, 1925. Yarns, treating with liquids, gases, and vapours.-Delustred yarns, threads &c. comprising cellulose acetate, are relustred by treating with a solvent or swelling agent for cellulose acetate, and afterwards treating the materials with steam under such conditions as to prevent the deposition of moisture on the goods. The steam must be dry or substantially dry, and is preferably employed under pressure. In cases where the cellulose acetate fibre contains residual solvent, particularly high 'boiling point solvent, treatment with a solvent or swelling agent may be omitted, lustre being restored by the application alone of dry or substantially drv steam. The lustre obtained closely resembles that of natural silk, the goods nevertheless retaining the bulky and voluminous character imparted by the delustring operation. Suitable solvents or swelling agents are organic acids such as acetic and formic acids, alcohols such as ethyl alcohol, esters suc'h as ethyl acetate, and salt solutions such as solution of calcium sulphocyanide. The solvent or swelling agent may be employed in 'aqueous solution. The goods may be treated w.ith a paste containing the solvent or they may be immersed, wholly or partly, in baths containing the solvent or swelling agent, and to such baths may be added dyestuffs, salts, mordants, and protective colloids; the treated goods are dried quickly under tension, and then steamed. In an example, delustred cellulose acetate yarn is immersed in dilute acetic acid at 50‹ U., quickly dried, and steamed under pressure. Specification 206,818 is referred to.