Patent GB-323501-A (GB)
Title: Improvements in the treatment of materials made of or containing cellulose esters or ethers
IPC: D06M13/188
Filed: 1928-07-31
Abstract: 323,501. British Celanese, Ltd., and Ellis, G. H. July 31, 1928. Yarns, treating with liquids.-Materials made of or containing organic esters of cellulose, for example cellulose formate, acetate, propionate or butyrate, or cellulose ethers, for example methyl, ethyl or benzyl cellulose, or the condensation products of cellulose and glycols or other polyhydric alcohols or the products obtained by treating alkalized cellulose with esterifying agents, for example " immunized cotton " obtained by treatment with p-toluene sulphochloride are treated to form insoluble metallic soaps in the materials. Materials treated in this manner are much more impervious to water and may also have a reduced lustre. The metallic radicle is applied while the cellulose derivative is in a swollen condition. A solution of the soluble metallic compound may either be applied at such concentrations or under such conditions as to cause a swelling of the cellulose derivative or it may be applied in conjunction with or after treatment of the material with a swelling agent. Furthermore, if desirable a treatment of the material with a swelling agent may precede the treatment with the metallic compound even though the latter swells the material or is used in conjunction with a swelling agent therefor, or the metallic radicle may even be dissolved in the solution of the cellulose derivative used for the production of the materials. Suitable metals comprise heavy metals, for example tin, aluminium, iron or chromium or bismuth, zinc or antimony. They may be applied in the form of their soluble salts, for example as chlorides, sulphates or thiocyanates. Suitable swelling agents, particularly in aqueous solution, comprise acetic, formic, glycollic or lactic acids; ethyl alcohol, acetone, diacetone alcohol or diacetin ; phenol, hydroquinone, or other water soluble phenols or polyhydric phenols; thiocvanates, cyanates and urea, urethanes, thiourea, thiourethanes, guanidine or alkyl or other simple derivatives thereof. The insoluble soaps may be formed in the materials by any suitable treatment, for example the materials treated with the metallic compounds may afterwards be treated with solutions of soluble soaps or soap-acids or these may be applied in the solutions used to form the materials. As soaps there may be employed the customary salts of fatty acids, salts of sulphonated fatty acids or oils, resins, naphthenic acids and other soap-forming bodies or alternatively the free acids. Coloured waterproof materials may be obtained by suitably colouring the materials. They may be dyed with any of the customary dyestuffs for cellulose ester or ether materials before or after deposition of the insoluble metallic soaps. Moreover, such dyestuffs may, if desired, be incorporated in the soap or soap-acid solutions themselves so as to colour and waterproof the materials in one operation. In examples, a cellulose woven fabric is padded in a solution of tin chlorothiocyanate, batched, treated without prior washing with a soap solution, and then washed free from thiocyanate and dried or treated as desired; a cellulose woven fabric is treated with a solution of formic acid, immersed without rinsing in a. solution of stannic chloride, rinsed lightly and then immersed in a solution of ammonum-sulpho-ricinoleate or a salt of other sulphonated fatty acids, washed off well and dried or treated as desired; a cellulose woven fabric is dyed black by applying tolidine, tetrazotizing and developing with alpha-naphthylamine, again tetrazotizing and developing with #-oxynaphthoic acid in known manner, and then padded in a solution of chromium chloride and ammonium thiocyanate, batched, treated in a bath containing soap and ammonia, washed free from thiocyanate and dried or treated as desired. Materials consisting wholly of cellulose esters or ethers or comprising in addition any other fibres, for example cotton or artificial cellulosic fibres, for example viscose, cuprammonium or nitrocellulose artificial silk, wool or silk may be treated in this manner. The Provisional Specification refers also to the forming of insoluble metallic soaps on the materials.