Patent GB-463074-A (GB)
Title: Improvements in the production of artificial filaments, films and like materials
IPC: D01F2/30
Filed: 1935-09-23
Abstract: Artificial filaments, films, and similar products are obtained by imparting the required shape to a solution of a cellulose derivative, polymerized vinyl or acrylic ester, rubber or rubber substitute, or other base material, in a solvent medium containing volatile inflammable liquid, and effecting setting of the shaped solution by means of an evaporative medium containing vapour of a volatile halogenated hydrocarbon, the concentration of which in the outgoing evaporative medium is not greater than 10 per cent of the concentration of the inflammable liquid vapour.  The halogenated hydrocarbon may be present in the solvent medium in a proportion not greater than 10 per cent of the weight of the inflammable liquid. The process is preferably carried out in a spinning cell or chamber. The presence of the halogenated hydrocarbon reduces the risk of explosion.  If desired it may be introduced into the spinning cell together with additional evaporative medium.  Methylene or ethylene dichloride, dichlorethylene, carbon tetrachloride, or trichlorethylene, may be employed.  The inflammable liquid may be acetone, ethyl ether, methylene ethylene ether, petroleum ether, dioxane, or benzene. The cellulose derivative may be cellulose acetate or other organic derivative, or cellulose nitrate.  The evaporative medium may also contain a non-inflammable gas such as carbon dioxide or nitrogen.  In an example, a solution of cellulose acetate in a mixture of acetone and methylene dichloride, or acetone, ethylene dichloride, and ethyl alcohol is extruded into a spinning cell and the filaments are solidified by means of a current of air. Specifications 325,233, [Class 2 (ii)], 341,075, 396,792, and 397,114 are referred to.ALSO:Artificial filaments, films, and similar products are obtained by imparting the required shape to a solution of rubber or rubber substitute, in a solvent medium containing volatile inflammable liquid, and effecting setting of the shaped solution by means of an evaporative medium containing vapour of a volatile halogenated hydrocarbon, the concentration of which in the outgoing evaporative medium is not greater than 10 per cent of the concentration of the inflammable liquid vapour.  The halogenated hydrocarbon may be present in the solvent medium in a proportion not greater than 10 per cent of the weight of the inflammable liquid. The process is preferably carried out in a spinning cell or chamber. The presence of the halogenated hydrocarbon reduces the risk of explosion.  If desired it may be introduced into the spinning cell together with additional evaporative medium. Methylene or ethylene dichloride, dichlorethylene, carbon tetrachloride, or trichlorethylene, may be employed.  The inflammable liquid may be acetone, ethyl ether, methylene ethylene ether, petroleum ether, dioxane, or benzene.  The evaporative medium may also contain non-inflammable gas such as carbon dioxide or nitrogen. Specifications 325,233, [Class 2 (ii)], 341,075, 396,792, and 397,114, [all in Group IV], are referred to.