| 摘要 |
1282107 Nylon yarn MONSANTO CO 18 Aug 1969 [21 Aug 1968] 41182/69 Heading B5B [Also in Division D1] Continuous filament nylon yarn e.g. a 500 denier tyre cord, of high tenacity and elongation is produced by a process which comprises drawing the yarn to a tenacity of at least 8À5 grams per denier, subjecting the yarn to a temperature of 180-235‹ C. for a period of 0À003-0À15 seconds whilst at a reduced tension of 0À05-0À35 grams per denier, then collecting the yarn in orderly manner. The yarn retains a tenacity of at least 8À5 grams per denier and has an elongation (expressed as length by which yarn can be stretched before breakage divided by the original drawn length of the yarn) such that the product of tenacity and elongation is at least 1À65. As shown, undrawn yarn 20 is drawn and molecularly oriented by passage between nip rolls 28, around draw pins 30, across a fixed heater block 32 in a zone of high tension leading to draw and separator rolls 34 and 36. Yarn next contacts hot plate 24 while under reduced tension, passing over roll 38 and through a guide 40 to ring and traveller take-up mechanism 26 whereby it is wound on to bobbin 42. Mechanism 26 may be replaced by winding apparatus which does not impart twist and/or nip rollers or a driver roller may be inserted between mechanism 26 and plate 24 to isolate the latter from tension variations originating in the take-up mechanism.
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