Patent GB-333504-A (GB)
Title: Improvements in or relating to the manufacture and treatment of materials made of or containing organic derivatives of cellulose
IPC: D01F2/28
Filed: 1929-02-05
Abstract: 333,504. British Celanese, Ltd., and Taylor, W. I. Feb. 5, 1929. Cellulose esters and ethers, processes for making filaments from.-Filaments, threads, yarns, or other materials, such as ribbons, tapes, or straw, which are delustred or partly delustred or are capable of being completely delustred by a treatment with, for example, moist steam, water or aqueous alcohol, are produced by extruding solutions in organic solvents of cellulose acetate or other organic derivatives of cellulose, which solutions contain proportions of such wetting agents as are salts of organic carboxylic acids or organic sulphonic acids or sulphuric esters or salts thereof. The organic derivatives of cellulose employed are only such as are soluble in organic solvents and are insoluble in water or in aqueous caustic alkali. The organic solutions containing organic cellulose derivatives may be spun by dry or wet spinning methods. In the dry spinning process, the evaporation of the volatile solvent produces filaments having a content of the wetting agents and the filaments may be delustred or partly delustred by treatment, for example, with aqueous liquids either continuously with the dry-spinning of the filaments or subsequent thereto. In spinning by the wet spinning process, the water may be an organic liquid in which the wetting agent is insoluble, so that the filaments emerging from the bath contain a proportion of the wetting agent and may subsequently be delustred. Thus, for example, petroleum ether and benzene may be used when the wetting agents are neutral soaps of alkali metals, or benzene when ammonium stearate or lithium oleate are employed. Alternatively filaments of reduced lustre may be produced directly by wet-spinning into an aqueous bath, for example the baths described in Specifications 177,868 and 179,234. Aqueous spinning baths may be employed which contain solvents for the cellulose derivative in relatively high concentration. As wetting agents there may be employed, for example, salts of higher fatty acids, sulphonated higher fatty acids or salts thereof, salts of naphthenic acids, naphthene sulphonic acids or aromatic sulphonic acids and salts thereof, resin soaps, sulphonated naphthalene formaldehyde condensation products, alkylated aromatic sulphonic acids, such as isopropyl or butyl naphthalene sulphonic acid, and salts thereof, and sulphonated oils. In examples, a solution of cellulose acetate in acetone to which turkey red oil has been added either during the mixing of the solution or after the cellulose acetate has dissolved is dry spun and the filaments after collection, for example by means of a cop-spinning device, are steamed or treated with water or aqueous alcohol to reduce their lustre or alternatively the solution is spun into aqueous baths to give filaments of reduced lustre directly. When a separate delustring treatment is necessary, it may, for example, be deferred until the threads or yarns have been worked into fabrics and may in fact take place in the ordinary course of the washing, dyeing or other operations. The Provisional Specification refers also to the employment of wetting agents in the spinning baths whether or not they are employed in the spinning solution, the wetting agents in the bath being carried forward by the filaments which are then subjected to a delustring treatment.