Patent ID: 7823616
Filing Date: 2010-11-02
Classification: B60C,D02G,Y10T

Abstract:
1. A pneumatic radial tire comprising a pair of bead portions, a pair of sidewall portions, a tread portion continuing to both the sidewall portions, a carcass toroidally extending between the pair of bead portions, a belt disposed on a crown portion of the carcass outward in a radial direction of the tire and comprised of at least two belt layers, and at least one belt reinforcing layer disposed on the belt outward in the radial direction of the tire so as to cover a whole and/or both end portions of the belt and composed of a rubberized layer containing reinforcing elements substantially arranged in parallel to the circumferential direction of the tire, characterized in that the reinforcing element constituting the belt reinforcing layer is a polyketone fiber cord satisfying conditions of the following equations I and II: wherein σ is a thermal shrinkage stress in cN/dtex at 177° C.; and E is an elastic modulus in cN/dtex at 25° C. under a load of 49 N.