Patent GB-824138-A (GB)
Title: Sizing compositions for synthetic yarns
Inventor: COLWILL WILLIAM
IPC: D06M15/267
Filed: 1957-04-24
Abstract: Synthetic multi-filament yarns are sized by impregnation with an aqueous solution of partially hydrolysed polyacrylonitrile or partially hydrolysed polyalkyl acrylate wherein the alkyl group contains from 1 to 4 carbon atoms, together with a wetting-agent and optionally a lubricant, the aqueous solution having a pH value between 6.0 and 8.0.  The partially hydrolysed polyacrylonitrile or partially hydrolysed polyalkyl acrylate may be prepared by heating polyacrylonitrile or polyalkyl acrylate in the form of an aqueous slurry containing equivalent quantities or slight excess of alkaline hydroxides at 60-100 DEG  C. until completely water-soluble products are obtained, the degree of hydrolysis in the case of polyacrylonitrile preferably being between 50 and 95% and in the case of polyalkyl acrylates preferably being between 20 and 95%.  Anionic surface active agents, e.g. sulphonated methyl oleate, cationic surface active agents, e.g. cetyl trimethyl ammonium bromide, or non-ionic surface active agents, e.g. alkyl alcohol/ethylene oxide condensates, may be used, preferably in an amount varying between 0.01 and 0.5% by weight, based upon the total amount of size solution.  Suitable lubricants are oils, fats and waxes including tallow, paraffin wax, mineral and vegetable oils, and preferably stable emulsions of paraffin wax or self-emulsifiable oil formulations containing light mineral oils, the amount of lubricant used preferably being between 5 and 60% based on the weight of the partially hydrolysed polymer. Softeners and plasticizers, e.g. glycerol, polyethylene glycols and urea, and fungicides, e.g. sodium pentachlorophenate, may be added to the sizing composition. Preferred sizes contain between 4 and 10% total solids and from 2 to 6% by weight of solids are preferably deposited upon the yarns. Suitable synthetic yarns are nylon, acetate rayon, polyethylene terephthalate and acrylic fibres.ALSO:A size for synthetic multi-filament yarns comprises an aqueous solution of partially hydrolysed polyacrylonitrile or partially hydrolysed polyacrylonitrile or partially hydrolysed polyalkylacrylate wherein the allyl group contains from 1 to 4 carbon atoms, together with a wetting agent and optionally a lubricant, the aqueous solution having a pH value between 6.0 and 8.0.  The partially hydrolysed polyacrylonitrile or partially hydrolysed polyalkyl acrylate may be prepared by heating polyacrylonitrile or polyalkyl acrylate in the form of an aqueous slurry containing equivalent quantities or slight excess of alkaline hydroxides at 60-100 DEG  C. until completely water-soluble products are obtained, the degree of hydrolysis in the case of polyacrylonitrile preferably being between 50 and 95% and in the case of polyalkyl acrylates preferably being between 20 and 95%. Anionic surface active agents, e.g. sulphonated methyl oleate, cationic surface active agents, e.g. cetyl trimethyl ammonium bromide, or non-ionic surface active agents, e.g. alkyl alcohol/ethylene oxide condensates may be used, preferably in an amount varying between 0.01 and 0.5% by weight based upon the total amount of size solution.  Suitable lubricants are oils, fats and waxes including tallow, paraffin wax, mineral and vegetable oils, and preferably stable emulsions of paraffin wax or self emulsifiable oil formulations containing light mineral oils, the amount of lubricant used preferably being between 5 and 60% based on the weight of the partially hydrolysed polymer.  Softeners and plasticizers, e.g. glycerol, polyethylene glycols and urea, and fungicides, e.g. sodium pentachloro phenate, may be added.