GB546978A - Improvements in and relating to the manufacture and production of artificial threads, filaments and the like - Google Patents

Abstract

546,978. Artificial silk &c. ; dyeing processes. COURTAULDS, Ltd., and WORMELL, R. L. Feb. 6, 1941, No. 1579. [Classes 2 (ii) and 15 (ii)] Threads made from casein of animal or vegetable origin are subjected to a hardening treatment and are then impregnated with a solution of a normal alkali metal salt of an aliphatic dibasic acid containing at least six carbon atoms in the molecule, for a time, dependent on the temperature, sufficient to produce an improvement in the wet tenacity and other properties. The treatment also reduces the wet extensibility, and increases the fastness to washing after dyeing. The threads may be hardened by treatment with a salt such as an aluminium or chromium salt with or without formaldehyde. For the further treatment there may be used di-sodium adipate, or sebacate. The solution may also contain formaldehyde. In an example casein fibres are hardened and insolubilized by treatment with a solution containing formaldehyde and an aluminium salt. A skein of the dried fibres is wetted out with warm water and then soaked in an aqueous solution of basic chromium sulphate containing formaldehyde. After several hours treatment in the warm solution, the skein is removed, washed, and placed in a bath containing di-sodium adipate and formaldehyde. The temperature is maintained at 95‹C. for a few hours. The skein is then washed and dried.