GB156709A - Improved manufacture of cotton substitutes - Google Patents

Abstract

156,709. Ehrenthal, B. P. von. Aug. 7, 1919, [Convention date]. Materials, fibrous; pulp, preparation of.-Easily bleached cellulose fibres suitable as a cotton substitute, having a length corresponding to the length of ordinary cotton fibres, and usable direct in a cotton-spinning mill, and also as raw material for the manufacture of paper, nitro cellulose &c., is obtained from linseed and hempseed straw, jute, reeds, nettles, agave, potato haulm, willow bark and the lilie. The process comprises three operations, (i) hydrolysis, with weak inorganic or organic acids or their acid salts, whereby the incrusting substances, (lignin substances, pectose, pectinate of lime, pentose, &c.), are loosened and partly dissolved, (ii) chemical opening, whereby incrusting and cementing or glutinous substances are completely dissolved and the fibre bundles and strands broken up into single cells. Diluted alkaline solutions of caustic soda, soda, ammonium compounds, milk of lime, and the like are used in boilers, with or without pressure. The boiling operation may be assisted by adding small quantities of organic solvents such as alcohol, carbon disulphide, acetone, petroleum, hydrocarbons and the like, which may afterwards be recovered and used again. The material is thoroughly washed, and to maintain the single cell fibres in easily separable condition when dry, they are subjected to a (iii) treatment with oleic and fatty acids or their salts, organic sulpho-acids, amides of fatty and oleic acids, and the like, used in aqueous solutions or emulsions, which may be warmed. The fibres so produced are flexible and soft. This (iii) treatment may be applied to fibrous material which has been opened by other processes. Specifications 11660/85, [Class 120, Spinning], and 23745/12, [Class 120 (1), Spinning, Preparation &c. for], are referred to.