GB470746A - Improvements in and relating to the manufacture of artificial structures and other useful articles from cellulose derivatives - Google Patents

Abstract

For the working-up of alkali soluble cellulose ethers in the manufacture of artificial silk, &c., films, plates, plastic masses, adhesives, cements, finishes, coatings, &c., there is employed as the coagulant for the cellulose ether solution, particularly the liquid solution, or to assist in such coagulation, a medium containing an alkali metal secondary carbonate, in particular sodium carbonate. The shaped structure such as a thread may be introduced directly into the medium, or it may be preliminarily coagulated in a neutral or alkaline bath. The alkali carbonate coagulant may also contain an inorganic or organic neutral salt and another alkali metal salt of alkaline reaction, and also glycerine, glucose, turkey red oil etc.; it may be used at temperatures above 40 DEG C., and the caustic alkali introduced during the coagulation may be neutralized by passing carbon dioxide into the bath. After treatment with the alkali carbonate, the product may be washed with water or may be treated with an acid, neutral or alkaline bath. The cellulose ethers employed may contain less than one ether group per 1--2 C6H10O5 units, and the ether groups may be alkyl, hydroxyalkyl or alkyl hydroxyalkyl. In examples illustrating the manufacture of threads, films, cements, adhesives and plates and the finishing and printing of textiles there are described suitable processes for the manufacture of the cellulose ethers, and also methods for working up their, solutions these being used as primary coagulation baths solutions of sodium carbonate of 10--36 per cent, and of sodium carbonate baths containing sodium sulphate, glucose, glycerine, borax, sodium sulphite, sodium bicarbonate, and caustic soda, such baths being at temperatures of 20--90 DEG C., or there are used primary coagulation baths of sodium sulphate, ammonium sulphate or ammonium chloride followed by an alkali carbonate bath as stated above. Baths of sodium bicarbonate at temperatures above 50 DEG C. may also be used. Specifications 25246/11, [Class 2 (iii)], 177,810, 200,816, 200,834, 203,346, 203,347, 231,807, 231,808, 231,809, 231,810, 231,811, 281,352, 312,197, 319,293, 323,731, 323,732, [all in Class 2 (ii)], 341,899, 356,776, 374,964, 390,517, 408,932, 408,950, 412,864, 459,122, 459,123, 462,456, 462,712, and 462,713 are referred to.