| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pneumatic tire in which a run-flat durability and a high-speed durability under a normal state are improved and eccentric wears at the central part and both ends of a tread are restricted. Ž<P>SOLUTION: This pneumatic tire comprises a bead part 1, a carcass layer 4 extending through both sides 2 up to both beads 1, a belt ply 8 of at least two or more layers, a peripheral belt reinforcing ply 9, and a side reinforcing rubber ply 5. The peripheral belt reinforcing ply 9 is divided into three areas of a central area 9A and both side areas 9B, a cord constituting both side areas 9B is a polyketone fiber cord having several filament twisted bundles of polyketone, wherein the polyketone fiber cord fulfills formula (I): σ≥-0.01E+1.2 and formula (II): σ≥0.02 and cords constituting a central area A are organic fiber cords having a lower tensile strength at the time of extension by 2% at 150°C as compared with that of polyketone fiber, and a higher tensile strength at the time of extension by 2% at 25°C. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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