Patent GB-665462-A (GB)
Title: Improvements in or relating to a method for improving the strength of artificial insolubilised protein filaments or fibres
IPC: D06M11/155
Filed: 1948-08-03
Abstract: Artificial insolubilized wet spun protein filaments or fibres, which have been dyed in acid dye baths subsequent to their insolubilization, are treated in an aqueous solution of a salt, the metal of the cation of which is selected from the group consisting of mercury, chromium, uranium, zinc, cadmium or aluminium, to improve the strength thereof.  The treatment may be carried out under tension.  The process is particularly applied to those filaments or fibres obtained by wet spinning and insolubilized by formaldehyde in the presence of an acidified strongly saline solution, such as those produced from alkaline solutions of casein and vegetable globulins such as peanut and soya bean globulin.  The preferred salts are mercuric acetate, uranylacetate, basic chromium sulphate, aluminium sulphate, zinc chloride and cadmium acetate, and preferably the solutions should, except in the case of mercury salts, contain formaldehyde.  Dyeing may be carried out using acid levelling dyes, acid milling dyes, or chrome dyes.  The ratio of the weight of metallic salt solution to the weight of fibres should be of the order of 30 : 1.  In an example, insolubilized groundnut protein fibre is dyed in liquor containing Solway Blue PFN 125, sulphuric acid and sodium sulphate.  A length of dyed fibre is stretched to a maximum in 3 per cent mercuric acetate in O.IN acetic acid at 70 DEG  C. for 30 minutes, washed and dried at 105 DEG  C.  The increase in wet strength as a result of treatment is of the order of 200 per cent, and in dry strength of the order of 100 per cent.  If the treatment is given without stretching an increase in wet strength of 40 per cent and in dry strength of 25 per cent is obtained. Specifications 482,974, 513,910, 533,952, 536,104, 597,497, 639,342, 639,363 and 657,686 also are referred to.ALSO:Artificial insolubilized wet spun protein filaments or fibres, which have been dyed in acid dye baths subsequent to their insolubilization, are treated in an aqueous solution of a salt, the metal of the cation of which is selected from the group consisting of mercury, chromium, uranium, zinc, cadmium or aluminium, to improve the strength thereof.  The treatment may be carried out under tension.  The process is particularly applied to those filaments or fibres obtained by wet spinning and insolubilized by formaldehyde in the presence of an acidified strongly saline solution, such as those produced from alkaline solutions of casein and vegetable globulins such as peanut and soya bean globulin.  The preferred salts are mercuric acetate, uranyl acetate, basic chromium sulphate, aluminium sulphate, zinc chloride and cadmium acetate, and preferably the solutions should, except in the case of mercury salts, contain formaldehyde.  Dyeing may be carried out using acid levelling dyes, acid milling dyes, or chrome dyes.  The ratio of the weight of metallic salt solution to the weight of fibres should be of the order of 30 : 1.  In an example insolubilized groundnut protein fibre is dyed in liquor containing Solway Blue PFN 125, sulphuric acid and sodium sulphate.  A length of dyed fibre is stretched to a maximum in 3 per cent mercuric acetate in O.1N acetic acid at 70 DEG  C. for 30 minutes, washed and dried at 105 DEG  C.  The increase in wet strength as a result of treatment is of the order of 200 per cent, and in dry strength of the order of 100 per cent.  If the treatment is given without stretching an increase in wet strength of 40 per cent and in dry strength of 25 per cent is obtained. Specifications 482,974, 513,910, 533,952, 536,104, 597,497, 639,342, 639,363, and 657,686, [both in Group IV (a)], are referred to.