| 摘要 |
1,063,013. Drawing polyester filamentary yarns. IMPERIAL CHEMICAL INDUSTRIES Ltd. Jan. 27, 1965 [Feb. 20, 1964], No. 7162/64. Heading B5B. In processes in which filamentary yarns composed of synthetic linear polyesters or copolyesters are drawn by passage over a heated feed roll and a heated draw roll, the draw roll surface temperature is at least 150‹ C. and relaxation of the drawn yarn takes place on the draw roll, said relaxation being controlled by adjusting the tension in the yarn leaving the draw roll to a value less than the tension in the yarn passing from the feed to the draw roll. The tension of the yarn leaving the draw roll may be between 0À02 and 0À5 gram per denier. The yarn may contact a heated plate maintained at a surface temperature of 180-220‹ C. between the feed and draw rolls. The yarn may be composed of a polyester or copolyester at least 85% of the acid residues in the polymer chains of which are terephthalic acid residues. The yarn may be composed wholly of polyethylene terephthalate. The feed roll surface temperature may be 60‹ to 100‹ C. The draw roll may have a surface speed of up to 500 feet per minute and a surface temperature of 150‹ to 230‹ C.
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