GB656728A - Sizing or coating yarns, fabrics, films, and other structures composed of synthetic linear fibre-forming polymers - Google Patents

Abstract

Yarns or other structures composed of synthetic linear fibre-forming polymers are coated first with an anchoring composition containing a tannic acid and then with a sizing or other coating substance. As the tannic acid there may be used gallic acid, di-gallic acid, or the various tannins. The linear polymer may be a polyamide, polyester, polyether, polyacetal, polyvinyl compound, or polyethylene. The process may be applied to the coating or sizing of yarns, woven and knitted fabrics, staple fibres, or monofils. The sizing or coating substance may be sodium cellulose glycollate, gum arabic, casein, soya protein, p blood, blood albumin, egg albumin, gliadin, peanut protein, natural gums; degraded starches such as hydrolyzed starch, British gum, dextrin; starch derivatives such as methyl starch, glycol starch, starch glycollic acid; cellulose derivatives such as glycol cellulose, cellulose acetate phthalate; partially saponified polyvinyl acetates, polyvinyl alcohol, acetals of polyvinyl alcohol, or other polyvinyl alcohol derivatives; polyethylene oxide; water-soluble polyamides. Plasticizers, corrosion inhibitors, preservatives, and fillers, may be incorporated in the tannic acid solution or in the film-forming top-coat. In an example, nylon yarn is soaked in a 1 per cent aqueous solution of tannic acid, with 0.15 per cent of oxalic acid to prevent staining. After removal from the solution and after centrifuging, the yarn is soaked in an aqueous solution of partially saponified polyvinyl acetate containing boric acid. In another example, nylon yarn is treated with the tannic acid solution while on a twisting machine and just before being wound up. After drying, the yarn is sized with saponified polyvinyl acetate while travelling from bobbin to bobbin and is then coned while applying olive oil. The yarn is knitted and the size is removed from the fabric by washing with hot water containing trisodium phosphate, oxalic acid, and sodium cetyl sulphate. In other examples, the top-coat comprises water-soluble methyl cellulose, oxidized corn starch, water-soluble starch acetate, or a water-soluble interpolymer prepared from triglycol diamine, hexamethylene diamine and adipic acid. Specifications 260,290, [Class 15 (ii)], 487,734, 553,303, 554,268 and 557,783 are referred to.ALSO:Structures and articles composed of synthetic linear polymers are coated first with an anchoring composition containing a tannic acid and then with the desired coating composition, which may have a basis of sodium cellulose glycollate, gum arabic, casein, soya protein, blood, blood albumin, egg albumin, gliadin, peanut protein, natural gums, starches, starch ethers, glycol cellulose, cellulose acetatephthalate, polyvinyl alcohol, partially-saponified polyvinyl alcohol, polyvinyl acetal, polyethylene oxide, or water-soluble polyamides. The linear polymer may be a polyamide, polyester, polyether, polyacetal, polyvinyl compound, or polyethylene. The process may be applied to the coating of tubes, rods, and moulded articles. Two or more coats of the anchoring composition of the the top-coat may be applied. Specifications 487,734, 553,303 and 554,268, [all in Group IV], are referred to.