| 摘要 |
<p>Described is a low flammability multifilament yarn especially for use in industry, composed of a polyester formed from dicarboxylic acid and diol components which contains, in the polymer chain, units of the formula I <IMAGE> where R is a saturated open-chain or cyclic alkylene, arylene or aralkylene radical, and R<1> is an alkyl radical of up to 6 carbon atoms or an aryl or aralkyl radical, characterised in that it has a tenacity (F) of at least 65 cN/tex, a total burn time, when made into a loomstate cloth and subjected to the flammability test of DIN 4102/B2, which is at least 5, preferably 10, times shorter than that of a comparable loomstate cloth composed of a non-phosphorus-modified polyester, and in that no afterburning occurs on 3 and 15 sec flaming according to DIN 54336 and 3 sec flaming according to DIN 54333. Also described is a process for producing this polyester yarn by subjecting filaments which have been spun at a spinning take-off speed of above 300 m/min to at least two-stage drawing, each stage being carried out at a defined temperature and to a defined portion of the total draw, and optionally to a setting and relaxing treatment at defined temperatures and a defined shrinkage ratio. Also described are various uses for the yarn.</p> |
