PNEUMATIC RADIAL TIRE AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To provide a pneumatic radial tire and a manufacturing method therefor allowing improvement of a high-speed durability and a high-frequency road noise during high-speed running. SOLUTION: This pneumatic tire uses an acryl-based fiber cord of a tensile strength above 4.5 g/d and an intermediate elongation of 2.0-4.5% under 2.25 g/d load as a reinforcing cord of a belt cover layer 10. The pneumatic tire is manufactured as follows. By dip-processing the acryl-based fiber cord in a water-based mixture (RFL) and heat-treating it at a temperature of 160-200 deg.C, the acryl-based fiber cord of the tensile strength above 4.5 g/d and the intermediate elongation of 2.0-4.5% is obtained. An unvulcanized tire is formed by using the acryl-based fiber cord for the belt cover layer 10, then the tire is vulcanized and formed.