Polyesterfaeden

摘要

1285584 Cellular polyester filaments TORAY INDUSTRIES Inc 30 Oct 1969 [30 Oct 1968 12 Feb 1969 (2)] 53334/69 Heading B5B [Also in Division C3] Polyester filaments contain 0À4-5% by weight of a polyalkylene ether and 0À3-3% by weight of a surface-active metal salt, and have fine pores aligned along the filament axis. The polyester is a fibre-forming polyester, preferably one in which at least 60% by weight of the recurring units are ethylene terephthalate units, and may thus be polyethylene terephthalate homopolymer, a copolyester obtained by copolymerizing ethylene terephthalate with a known dihydroxy component, dicarboxylic acid component or hydroxy carboxylic acid component; a polyester blend obtained by melt mixing an ethylene terephthalate homopolymer or copolymer with another homopolyester or copolyester; an ethylene terephthalate copolymer containing amide, urethane, ether, carbonate or other linkages; a fibre-forming polyester other than polyethylene terephthalate; and a fibreforming polyester ether. The polyalkylene ether preferably has a molecular weight greater than 4000. The metal salt may be an alkali metal sulphonate, preferably containing only one sulphonate group which is terminal. The metal salt may be a metal salt of a carboxylic acid, phosphonic acid or sulphinic acid, or a di-metal or mono-metal salt of phosphoric acid or phosphorous acid. The filaments of the invention may be obtained by melt spinning a mixture of a polyester, polyalkylene ether and a surface active metal salt and causing fine pores aligned along the filament axis, to form in the filaments by treating the filaments with warm water or with a dilute aqueous solution of an alkali metal hydroxide to dissolve out some of the polyalkylene ether present in the filaments. In an example a mixture of (A) polyethylene terephthaltae and (B) a 2 : 1 mixture of polyethylene glycol having a number average molecular weight of 20,000 and sodium dodecylbenzenesulphonate, the mixing ratio of (A) to (B) being 92À5 : 7À5 is melt spun and the filaments thereby obtained are drawn at a draw ratio of 3À7 over a hot pin maintained at 100‹C. A wool-like texture is imparted to the drawn filaments by mechanical treatment at 205‹ C., and the filaments thereafter knitted to form a cloth. The cloth is scoured at 80‹C. with a very dilute aqueous solution of a detergent and soda ash and thereafter boiled for 20 minutes with a 0À3 N aqueous solution of sodium hydroxide. On analysis it is found that the proportions of polyethylene glycol in the cloth is 1À8% and the proportion of sodium dodecylbenzene sulphonate is 1À1% by weight. Examination of the treated yarn by optical and electron microscopes showed that minute longitudinal pores or cavities had been formed in the yarn.