Abstract: Process for preparing an industrial polyester multifilament yarn with high modulus and low shrinkage, in which polyethylene terephthalate polyester is wound at 2000 m/min or more to produce undrawn yarns with an intrinsic viscosity of 0.88 or higher and a density of 1.338 to 1.365 g/cm3, an oiling agent is provided to undrawn yarns, the resulting undrawn yarns are wound, drawn through three stages, heat set, relaxed, and wound again. The polyethylene terephthalate polyester yarn is produced by drawing undrawn yarns at a glass transition temperature (Tg, about 80° C.) or lower through three stages under conditions that a draw ratio of the 1st stage is greater than a draw ratio of the 2nd stage or a draw ratio of the 3rd stage and the draw ratio of the 3rd stage is greater than the draw ratio of the 2nd stage.

Abstract: Described in the present invention is a polyester multifilament yarn having a high modulus and low shrinkage which provides a treated cord having high tenacity and improved dimensional stability that can be advantageously employed as a fibrous reinforcement material of rubber products such as tires and belts.

Abstract: Disclosed is a process for preparing an industrial polyester multifilament yarn with high modulus and low shrinkage, in which polyethylene terephthalate polyester is wound at 2000 m/min or more to produce undrawn yarns with an intrinsic viscosity of 0.88 or higher and a density of 1.338 to 1.365 g/cm3, an oiling agent is provided to undrawn yarns, the resulting undrawn yarns are wound, drawn through three stages, heat set, relaxed, and wound again.

Abstract: Described in the present invention is a polyester multifilament yarn having a high modulus and low shrinkage which provides a treated cord having high tenacity and improved dimensional stability that can be advantageously employed as a fibrous reinforcement material of rubber products such as tires and belts.

Abstract: Disclosed is a process for preparing a high modulus and a low shrinkage polyester multifilament yarn of 1000 deniers or more at a spinning rate of 2,000 m/min or more, comprising the steps of: melt-extruding polyester chips having an intrinsic viscosity of 0.90 to 1.2 through a spinning nozzle and passing polyester chips through a heating zone; quenching melt-extruded yarns with the use of a radial in-to-out quenching method to solidify them; and providing spin finishes to solidified yarns before winding. The industrial polyester multifilament yarns have a coefficient of variation of 4.0% or less in a cross sectional diameter of filaments, and excellent uniformity of fineness. Treated cords formed from the industrial polyester multifilament yarns with high modulus and low shrinkage have an excellent dimensional stability and tenacity, and can be used as reinforcements of rubber goods such as tires.

Abstract: Described in the present invention is a high strength polyethylene naphthalate fiber which provides a treated cord having high tenacity and improved dimensional stability that can be advantageously employed as a fibrous reinforcement material of rubber products such as tires and belts.