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

摘要

526,206. Artificial filaments etc.; viscose. COURTAULDS, Ltd., STOKES, W. H., and ROSE, L. March 10, 1939, No. 7804. [Class 2 (ii)] Artificial filaments are obtained by extruding into a coagulating bath, viscose made from highly purified wood-pulp containing less than 0.5 per cent. of acetone-extractable matter, with which viscose at least one substance having the property of reducing the surface tension of the viscose has been incorporated. The added substance may be a resinous substance extracted from wood pulp, such as pulp resin soap obtained in the manufacture of Kraft pulp from pine wood or obtained from the medullary ray fibres separated mechanically from sulphite wood pulps. The added substance may be a terpene carboxylic acid, terpineol, a terpene compound sold under the Registered Trade Mark " Petrex," the essential constituent of which is 3-isopropyl-6-methyl-3.6-endoethylene-#4 -tetrahydro phthalic anhydride, a derivative of tauro-cholic acid, e.g. the sodium salt of tauro-cholic acid, an alkali salt of a sulphonated fatty acid or hydrocarbon, or a soap. The proportion of added substance is in general less than 0.5 per cent. The addition may be made at any stage of the manufacture of viscose. In an example, a purified wood pulp containing 0.12 per cent. of matter extractable by acetone is converted into viscose and during the dissolving step there is added a little ox-bile salt which comprises a mixture of sodium tauro-cholate and sodium glycocholate. The surface tension of the viscose is thus reduced. The solution is spun into an acid-salt bath. Specifications 340,564, 363,908, and 364,995, are referred to.