GB253477A - Process for preparing hollow artificial textile fibres from viscose - Google Patents

Abstract

253,477. British Enka Artificial Silk Co., Ltd., (Assignees of Naamlooze Vennootschap Nederlandsche Kunstzijdefabriek). March 5, 1926. Right to Patent relinquished. Cellulose xanthates, processes for making filaments from; alkali cellulose.-Hollow artificial textile fibres are prepared by employing a thin fluid viscose and by avoiding the usual precautions for preventing retention of gases in the fibre during the coagulation process, that is, by omitting the degasification of the viscose solution, or by employing a bath that coagulates the viscose rapidly. It is preferred to add a small quantity of a zinc salt to the coagulation bath. The thin fluid viscose mav be one that contains less than 8 per cent of cellulose, or one that is prepared from a strongly bleached cellulose, or from a soda cellulose which has been mercerized in the presence of an oxidizing agent or which has been subjected to an extended ripening process. To the viscose solution may be added pulverized solid material such as pumice powder, which promotes the separation of gas bubbles. In examples, the alkali cellulose is prepared by subjecting it to a ripening for 6 days at 24‹ C., or by adding sodium peroxide to the mercerizing lye, or by employing a cellulose that has been strongly bleached with sodium hypochlorite, and the viscose solution prepared from the resulting alkali cellulose is not subjected to the usual degasification, and to it may be added one per cent of finely-powdered pumice; or the viscose solution is prepared to contain 5 per cent of cellulose and then coagulated in a quickly-precipitating spinning-bath.