| 摘要 |
PROBLEM TO BE SOLVED: To reduce the load noise while improving the load noise, the high- speed durability and the steering stability. SOLUTION: A belt reinforcement layer 22 of a spiral structure including a PEN fiber cord is placed on the peripheral side of a belt layer 20 over a tread part. The Young's modulus E of the base rubber 16A of the tread part 16 is largely determined (100×105 through 150×105 Pa), and a half widthβW of the base rubber 16A is determined to be 55-80% of a belt half width BW. The cap rubber 16B is extended from an end part of the base rubber 16A outwardly in the tire width direction to cover an end part of the belt layer 20, and the loss factor tanδis largely determined (0.3-0.5). The tread part 16 is totally hardly vibrated by using the base rubber 16 of the large Young's modulus, and further the neighborhood of both end parts of the belt layer 20 as the loop of the vibration is covered with the cap rubber 16B of the large loss factor, the vibration can be effectively absorbed. |
