Patent GB-719489-A (GB)
Title: Improvements in the manufacture of articles from superpolyamides
IPC: D01F6/60
Filed: 1952-04-10
Abstract: Artificial filaments, films, ribbons, tubes, rods and other articles, and coatings, of dull appearance and having a high resistance to the degrading action of actinic rays, are made from a polyamide in which have been incorporated 0.5-5 per cent. of a delustring agent and also small proportions of both manganese and copper compounds. Alternatively the manganese and copper compounds may be incorporated in formed articles of a polyamide containing the delustring agent. The manganese and copper compounds may be hydroxides or salts of weak acids.  They may be incorporated in the starting materials or intermediate products used for making the polyamides, or they may be added to the molten polyamide or to a solution of the polyamide. Filaments may be made by melt spinning or by dry or wet spinning of the polymer solutions.  If desired the impregnation with manganese and copper compounds may be effected on manufactured articles such as fabrics, felts and knitted goods.  Preferably the proportion of manganese incorporated lies between 0.001 and 0.04 per cent., and that of the copper lies between 0.001 and 0.01 per cent. of the weight of the polyamide.  The polyamide may be formed from a diamine and a dibasic acid, or from an o -aminocarboxylic acid or the lactam of such acid.  In an example, filaments are obtained from polyhexamethylene adipamide containing 3 per cent. of titanium dioxide, 0.03 per cent. of manganese lactate hydrate and 0.008 per cent. of copper acetate.  In another example, a skein of filaments of a polyamide obtained from caprolactam and containing 3 per cent. of titanium dioxide is immersed in a solution containing water, formic acid and small proportions of manganese lactate and copper acetate. The skein is withdrawn, washed and dried.  Specification 689,629 is referred to.ALSO:Filaments, threads, fabrics, felts and other textile materials and articles made from delustred polyamides containing 0.5-5 per cent of a delustring agent are rendered resistant to the colouring and deteriorating action of actinic light by impregnating them with a solution containing both copper and manganese compounds. Preferably the solution contains a swelling agent for the polyamide, e.g. formic acid.  The textile materials treated may contain, in addition to the polyamide filaments, also filaments or fibres of cotton, linen, silk, rayon or synthetic materials such as polyesters or polyvinyl derivatives.  The manganese and copper compounds may be hydroxides or salts of weak acids.  Preferably the proportion of manganese incorporated lies between 0.001 and 0.04 per cent by weight based on the weight of the polymer, and the proportion of copper preferably lies between 0.001 and 0.01 per cent.  In an example, a skein of filaments of a polyamide obtained from caprolactam and containing 3 per cent of titanium dioxide is immersed in a solution containing water, formic acid and small proportions of manganese lactate and copper acetate. The skein is withdrawn, washed and dried. Specification 689,629, [Group IV(a)], is referred to.