Patent ID: 6382287
Filing Date: 2002-05-07
Classification: B60C,Y10T

Abstract:
A pneumatic radial tire comprising a carcass toroidally extending between at least a pair of bead cores and a belt superimposed on a crown portion of the carcass and comprised of a single slant belt layer containing a plurality of cords or filaments arranged at a given inclination angle with respect to an equatorial plane of the tire and at least one circumferential belt layer laminated on the slant belt layer and containing a plurality of cords arranged substantially in parallel to the equatorial plane, wherein each cord used in the at least one circumferential belt layer is made from polyethylene naphthalate fiber and has a layer twisting structure and a total denier DT of 1000d-6000d and a twist constant Nt=TÃ—(0.139Ã—DT/2Ã—1/&rgr;)Â½Ã—10âˆ’3&lE;0.5 wherein twisting number (twist turns/10cm) and &rgr; is a specific gravity, wherein a coating rubber for the at least one circumferential belt layer has a modulus of elasticity of not less than 200 kg f/mm2.