GB334030A - Improvements in spinning artificial silk - Google Patents

Abstract

334,030. I. G. Farbenindustrie Akt.- Ges. Oct. 2, 1928, [Convention date]. Cellulose xanthates ; processes for making filaments.-Viscose made from unpurified alkalicellulose and containing an excess of alkali with respect to the content of cellulose, is made into artificial silk by spinning into baths containing sulphuric acid of not more than 47 per cent strength, and if desired with the addition of salts such as sodium sulphate, or organic substances. During spinning the threads may be subjected to a stretching operation. The non-matured viscose may be prepared in the usual manner, but it is preferable to exclude oxygen by working in an indifferent atmosphere such as nitrogen. The viscose may be used directly for spinning or after a short maturing. Th viscose may be spun with additions such as reducing agents, mordanting agents, mucilage, oxalates, lactates, silicates, sulphonic acids, and substances for producing matt or aerated silk. The increased alkali content of the viscose results in solutions of reduced viscosity, and in spinning there are fewer breakages. In an example viscose containing 5 per cent of cellulose and 6.5 per cent of alkali is spun at 50‹ C. into a spinning bath containing dilute sulphuric acid more or less saturated with sodium sulphate. Specifications 135,205, 184,449, 184,450, 198,654, 234,188, 234,433, and 274,521, are referred to.