GB320062A - Process for improving vegetable fibrous material - Google Patents

Abstract

320,062. Lilienfeld, L. July 2, 1928. Yarns, treating with liquids.-Yarns consisting of or containing vegetable fibrous material such as cotton, flax, linen, hemp, ramie or jute are treated with a cellulose derivative containing the C S S group and from which cellulose can be regenerated, the material being treated with at least one shrinking-agent for the fibres, before during, or after the deposition of the cellulose. The treated material has the feel and elasticity of wool or linen, increased resistance to washing, rubbing, and sharp bending, and may acquire a high lustre and a silky appearance. The solution from which the cellulose is deposited, may contain viscose, a cellulose xantho fatty acid or a salt thereof, or cellulose zinc xanthate. Examples are given of viscoses containing down to 1.4 per cent of caustic soda and being prepared by pressing the alkali cellulose to the required amount and then dissolving the cellulose xanthate in the requisite amount of water. The viscose or other solution from which cellulose is regenerated is applied to the fabric or yarn by dressing, coating, filling, printing, impregnating, sizing, or weighting methods, and the solution may contain a dressing or sizing agent as starch, dextrin, albumen, gelatin; a softening-agent as glycerin, soap, Turkey red oil, glucose, castor oil, paraffin oil; a filling- agent as talc, china clay, lithopone; a pigment as zinc white, soot, mica ; a dyestuff, or any two or more of the above substances. When viscose solution is employed, it may also contain sodium sulphate, sulphite, bisulphite or thiosulphate, ammonium sulphate, alkali silicate, or aluminate or ammonia. In an example, a solution of cellulose xanthacetic acid in water containing a small amount of ammonia, aniline, or caustic soda producing a neutral solution is employed. The regeneration of the cellulose may be effected by heating or steaming or by a precipitating-bath such as Muller bath, for example as described in Specification 10094/06, [Class 2, Acids and salts, Organic &c.], or the precipitation may be effected in a shrinking-bath, containing caustic alkali or alkali sulphides in manner described in Specification 323,747, [Class 2 (ii), Cellulose &c.]. The shrinking agent may be caustic alkali, alkali sulphide, an organic sulphonium hydroxide as trimethyl sulphonium hydroxide, a quarternary ammonium base, an organic base as guanidine, sulphuric, nitric, phosphoric, or hydrochloric acid, or zinc or calcium chloride. Neutral or alkaline salts such as a thiosulphate, sodium chloride, sodium sulphate, alkali silicate, aluminate, zincate, phosphate, or acetate, borax, or water glass may be added to a neutral or alkaline shrinking-agent, while a salt having an acid reaction as alkali bisulphate may be added to a shrinking-agent having an acid reaction. The shrinking bath may further contain glycerine, alcohol, Turkey red oil, or soap. The process may be combined with that described in Specification 302,115 in which the regenerated cellulose has bubbles or hollow spaces dispersed throughout. The viscose may have gas dissolved or emulsified therein; the viscose may be mixed with a substance such as alkali carbonate caused to evolve gas when the material is exposed to an acid bath, the material then being treated with the shrinking agent ; or the gas may be evolved when the material such as alkali carbonate is brought into contact with an acid shrinking-agent, the coagulation of the cellulose, the shrinking of the vegetable fibres, and the evolution of the gas being effected in a single bath. The invention may be applied to the manufacture of artificial leather, the treated material resembling leather especially when treated with several layers of the regenerated cellulose, and the material may be rendered non- hygroscopic or water-repellant with a layer of a cellulose ester or other such as nitcrocellulose, celluloid, acetylcellulose, or an alkyl or aralkyl cellulose applied, is desired, together with a softening-agent as castor oil, tricresylphosphate, triphenylphosphate, a phthalic ester, camphor, &c.