Abstract: A substantially polyester drawn filament yarn composed of at least 15 filaments having a core zone surrounded by a sheath zone, said filaments havinga. a linear density of at least decitex 70;b. a tenacity of 735-1,000 mN/tex;c. a specific 5%-LASE higher than 375 mN/tex;d. a hot air shrinkage measured at 160.degree. C. of 0.5-3.7%;e. an average relative viscosity of 1.700 to 2.200; andf. an elongation at rupture of 5 to 20 percent, and a cord, a shaped elastomeric object, a tire, a sewing yarn, a seat belt, and a tow rope composed of the yarn.

Abstract: Manufacture of a multifilament polyester yarn which is suitable for use as an industrial yarn, particularly tire yarn, and displays a specific breaking strength at high spinning speeds, the yarn is made in accordance with a process comprising the successive steps of spinning a molten polymer through a plurality of holes, cooling and drawing the resulting filaments, and finally collecting them, the polymer flow in each of the spinneret holes exhibits a core portion having a higher relative viscosity and a sheath portion having a lower relative viscosity, the difference between said relative viscosities amounting to less than 0.100, preferably 0.040-0.003.

Abstract: The invention relates to a synthetic technical multifilament bicomponent yarn, which is particularly meant for use in safety belts, ropes and nets.The bicomponent yarn is preferably of the sheath-core type of which only the core contains a black pigment composed of carbon black particles and/or a reddish pigment composed of iron oxide particles and/or a whitish pigment composed of titanium dioxide particles of the rutil type, which pigments are insoluble in the polymeric material. The tenacity of the yarn may be about 70-85 cN/tex and the elongation at rupture of 7 to 15%.