| 摘要 |
1,236,239. Polyamide filaments. E. I. DU PONT DE NEMOURS & CO. 26 Sept., 1968 [29 Sept., 1967; 24 April, 1968], No. 45744/68. Heading B5B. [Also in Divisions D1-D2] In a process for the formation of twisted and heat-set, perhaps torque-balanced, yarn, a bundle comprising continuous filaments of a polyamide in which at least 50 mol. per cent of the repeating units have the formula (where X represents 1 or 2; Y represents an integer from 7-14; symbols R, which may be the same or different, each represent a hydrogen atom or a methyl group and at least 40% of the diamino constituent of the repeating unit has the trans-trans configuration) is melt-spun; drawn to a ratio of e.g. 1À9 using a draw roll at 120‹ C. and annealed (to obtain " orientation index " above 0À7) twisted to a " twist multiplier " above 1À5 and the twisted yarn is heattreated, at a temperature of between 55‹ C. and the second order transition temperature of the polymer, e.g. in an atmosphere of high humidity or superheated steam, to a " liveliness multiplier " of less than 0À4. |
