| 摘要 |
PROBLEM TO BE SOLVED: To provide a pneumatic radial tire capable of effectively improving braking performance without deteriorating hydroplaning-resistant performance on a wet road surface. SOLUTION: In the tire, a plurality of circumferential grooves 17 continuously extending to the circumferential direction and a plurality of lateral grooves 12, 15 extending to a tread width direction are provided on the tread surface of a tread part. A rib 11 continuously extending to the circumferential direction is provided on the inner side part 8 positioned at the inner side of the vehicle than an equator line E of the tire in a mounting attitude to the vehicle. The number of blocks (N<SB>iN</SB>) on the circumference of a shoulder block row 10 formed on the inner side part 8 is set 50 to 90, the number of blocks (N<SB>OUT</SB>) on the circumference of the shoulder block row 14 formed on the outer side part 9 positioned at the outer side of the vehicle in the same attitude is set 40 to 70, and the ratio (N<SB>iN</SB>/N<SB>OUT</SB>) of the number of blocks is set in the range of 1.1 to 1.5. COPYRIGHT: (C)2008,JPO&INPIT |
