METHOD FOR MANUFACTURING YARN FOR HIGH-STRENGTH POLYETHYLENETEREPHTHALATE TIRE CORDS, METHOD FOR MANUFACTURING TIRE CORDS USING SAME, AND HIGH-TENACITY POLYETHYLENETEREPHTHALATE TIRE CORDS MANUFACTURED THEREFROM

摘要

To provide a method for manufacturing tire cords having an excellent shrinkage rate and an excellent tenacity utilization rate without causing reduction of the strength of polyethyleneterephthalate yarn and the tenacity of tire cords, the present invention provides a method for manufacturing high-tenacity dipping-treated polyethyleneterephthalate tire cords, characterized by increasing both of a spinning draft and a stretching ratio, wherein undrawn yarn is manufactured with 1,000 or more of a spinning draft and a 2,800-3,500 m/min of a spinning rate, and polyethyleneterephthalate yarn is manufactured by drawing the undrawn yarn in multi-steps with 5,800-7,000 m/min of a final wrapping speed and 1.5-2.0 of a stretching ratio, and then raw cords are manufactured by spinning the polyethyleneterephthalate yarn, and finally the raw cords are dried and heat treated after being dipped into a dipping solution. The tire cords are characterized by having 24.5 Kgf or more of tenacity and 3.6% or less of middle ductility and 5.8% or less of a shape stability index.;COPYRIGHT KIPO 2014;[Reference numerals] (AA) Comparative example 1; (BB) Comparative example 2; (CC) Example 1