| 摘要 |
<p>Disclosed is a pneumatic radial tire having improved flat spot resistance without sacrificing its high-speed durability, when a belt auxiliary reinforcement layer (6) thereof is constituted of a hybrid fiber cord (62) including a general-purpose nylon as a low-elastic fiber yarn. In the pneumatic radial tire, the belt auxiliary reinforcement layer (6) is formed by winding an organic fiber cord around the outer periphery of belt layers (4,5) in the tire circumferential direction. The organic fiber cord constituting the belt auxiliary reinforcement layer is obtained by twisting a highly-elastic fiber yarn (6p) with an elastic modulus of 10000 MPa or more and a low-elastic fiber yarn (6q) made of nylon (46).</p> |
