| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pneumatic radial tire which enhances crack resistance without degrading uneven wear resistance of the tire. <P>SOLUTION: In the pneumatic radial tire, a belt 3 made of at least one belt layer and a tread 4 are provided in order on a radial outside of a carcass 2 straddling in a toroidal shape between a pair of bead portions, and a plurality of main grooves 5 elongated in a tread circumferential direction are provided on a tread surface of the tread 4. A sub-groove 6 elongated in a tread circumferential direction is provided on a tread surface of the tread between a width-direction outermost main groove 5 of the circumferential main grooves 5 and an tread end TE in a width direction. A concave part 8 with a shape convexly curved to a width direction inside is provided on an outer surface 7 of the tire in a radial outside with respect to a belt layer on a radial inside among one or more belt layers. In the concave part 8, a part as large as/larger than half a width-direction cross-sectional area is positioned in a radial inside with respect to the groove bottom of the sub-groove 6. <P>COPYRIGHT: (C)2013,JPO&INPIT |
