GB535012A - New process for manufacturing protein fibres - Google Patents

Abstract

535,012. Artificial fibres. IWAMAE, H. July 21, 1939, No. 21192. Convention date, July 26, 1938. [Class 2 (ii)] Artificial fibres are produced by extruding an alkaline solution of a protein into an acid bath and then passing the coagulated fibres into a buffered solution having a pH value corresponding approximately to the iso-electric point of the protein. The spinning solution employed may be a solution of casein, soyabean protein or fish protein in caustic alkali and it may contain such additions as carbon disulphide, glucose, glycerine and salts. A suitable acid coagulating bath is one containing sulphuric acid and a sulphate such as sodium sulphate while the buffer in the second bath may be a mixture of sodium acetate and acetic acid. Preferably; however, there is employed as buffer solution the supernatant portion of the extraction liquid from which the soya-bean or fish protein has been precipitated, since this liquid has a pH value nearly equal to the iso-electric point of the protein of which the fibres are made. The buffered solution of the second bath may contain hardening agents for the protein such as formalin, phenol, acetone, tannin and alcohol. The fibres produced are given a final hardening treatment with formalin solution or vapour before drying. In an example, soya-bean protein is dissolved in as small a quantity as possible of caustic alkali and extruded into a bath containing 15 per cent. sulphuric acid and 20 per cent. sodium sulphate. The fibres are then passed into a buffer solution of dilute acetic acid and sodium acetate of pH 4.0 to 5.0 containing 5 per cent. phenol, 5 per cent. formalin and 10 per cent. alcohol. The fibres are finally passed through formalin solution or vapour.