Patent GB-649044-A (GB)
Title: Improvements in and relating to the manufacture and production of artificial threadsfrom viscose
IPC: D01F2/08
Filed: 1948-02-09
Abstract: In the production of artificial threads from viscose the aqueous coagulating bath (or an aqueous processing liquid applied to the thread after it is drawn from the coagulating bath) contains sulphuric acid, one or more metallic salts, an oil and an oil-soluble cation-active compound, which may be taken as such or formed in the coagulating bath or processing liquid.  The oil may be a mineral oil such as a "white oil," a non-drying fatty oil, for example olive oil or a liquid wax, e.g. sperm oil.  It may be present in an emulsified form resulting from the use as an emulsifying agent of a polyglycol ester, e.g. sorbitan trioleate modified with ethylene oxide, or the use of a polyglycol ether obtained by reacting 2-12 mols. of ethylene oxide with one mol. of a fatty alcohol having not less than 10 carbon atoms in the chain.  The aqueous processing liquid may be employed as a hot bath in which the threads are stretched shortly after being led from the coagulating bath.  The threads may be produced from viscose by a continuous process, the threads after their formation in the coagulating bath being subjected without any break to a series of treatments (including that with the processing liquid) and to drying and winding on to a package.  The cation active compound or compound giving rise thereto may be: (1) a condensation product of the general formula R-CO-(NHC2H4)n-NH2 in which R is a group with not less than 10 carbon atoms in the chain and n is an integer of 1 to 5.  These compounds are obtained by condensing a long chain fatty acid with an aliphatic polyamine, e.g. by condensing 1 mol. of oleic, stearic or palmitic acid or a mixture of these acids with 1 mol. of diethylene triamine, triethylene tetramine or pentaethylene hexamine or a mixture of these polyamines.  (2) Condensation products of the general formula R-CO-(NHC2H4)n-NH(R1R11X) in which R is group with not less than 10 carbon atoms in the chain, n is an integer of 1 to 5, R1 and R11 are alkyl groups, for example methyl or ethyl groups, and X is an anion, for example Br- or HSO4-.  These products may be obtained by alkylating the condensation products from long chain fatty acids and aliphatic polyamines of class 1 by treatment with an alkyl halide or a dialkyl sulphate, for example dimethyl or diethyl sulphate.  (3) Condensation products obtained by reacting a fatty acid having not less than 10 carbon atoms in the molecule, for example stearic acid, with an alkanolamine, for example mono-ethanolamine, and also the products obtained by reacting such condensates with an alkylene oxide, for example ethylene oxide, the proportion of the latter being sufficiently restricted to retain the oil-soluble properties of the product.  (4) Condensation products obtained by reacting a long chain aliphatic primary amine, for example octadecylamine, with an alkylene oxide, for example ethylene oxide, until a product is formed which is just dispersible in water. (5) Condensation products obtained by reacting a long chain aliphatic primary amine with ethylene oxide and alkylating the product obtained by treatment with an alkyl halide or a dialkyl sulphate, for example with dimethyl or diethyl sulphate.  The general formula of the condensation products obtained is (R, R1, R11, X)N-C2H4-(C2H4O)n-OH in which R is a group with not less than 10 carbon atoms in the chain, R1 and R11 are alkyl groups, X is an anion, for example Br-, or HSO4-, and n is an integer of 1 to 20; the value of n is dependent on the chain length of R and an increase in the value of n is necessary with an increase in the chain length of R in order to obtain an oil-soluble product.  For example, when R has 12 carbon atoms, n is 1 or 2 and when R has 16 carbon atoms, n is 5 to 7.  In an example, viscose rayon thread is withdrawn from an aqueous coagulating bath and is passed over a thread-advancing reel in a number of helical turns.  While passing over the reel, the thread is sprayed with an aqueous solution containing 1.5 per cent of sulphuric acid, 5.0 per cent of sodium sulphate, 0.2 per cent of zinc sulphate and 0.2 to 2 per cent of emulsified mineral oil containing 3 per cent of cetyl polyglycol ether and 1 to 2 per cent of an oil-soluble cation-active compound obtained from equimolecular proportions of oleic acid and triethylene tetramine.  The use of the oil and the cation-active compounds according to the invention is said to prevent the formation of hard deposits on the thread guides, godets and thread-advancing reels.  Specifications 467,500, 469,817, 541,099 and 640,105 and U.S.A.  Specification 2,394,519 are referred to.