Improvements in and relating to the production of artificial filaments, threads and the like from viscose

摘要

Viscose rayon is produced by extruding viscose to which has been added at least 0.1 millimol., and preferably between one and five millimols. per 100 grams of viscose of a mercaptothiazole having the general formula where X represents a benzene ring, a substituted benzene ring or a naphthalene residue and M represents hydrogen, or a metal, or a basic ammonium or amine radical, into an aqueous coagulating bath containing sulphuric acid, sodium sulphate, and zinc sulphate (preferably 1/2 to 15 per cent). In the example, viscose containing 7.4 per cent of cellulose, 7.0 of caustic soda and 1.1 of combined sulphur is prepared in the usual manner, 1.5 millimols. per 100 grams of the viscose of the sodium salt of mercapto benzthiazole are added, the viscose mixed for one hour, ripened for 48 hours to a salt point of 5.7 and spun into an aqueous coagulating bath at 48 DEG C. containing 9.5 per cent of sulphuric acid, 20 per cent of sodium sulphate and 4.5 per cent of zinc sulphate. The modified regenerated cellulose filaments obtained by the process of the invention have a skin substantially thicker than that normally obtained and by adjusting the proportion of mercapto thiazole added, filaments with non-crenulated surfaces are obtained. The process of the invention enables unripened viscose to be spun.