| 摘要 |
PROBLEM TO BE SOLVED: To achieve a pneumatic tire and its manufacturing method, wherein a level difference resulting from a production method employing split molds can be prevented, and a tire wear can also be effectively prevented for improving the life cycle against wear. SOLUTION: In an area extending from the shoulder 20 side end of a tread 16 to cover 5% to 20% of the tread width, a supplementary groove 24 extending along the tire circumference is formed, the supplementary groove 24 having a depth equal to 5% to 30% of that of a lug groove, and a width equal to 0.5% to 3% of that of the tread, wherein a one-side wear of the shoulder 20 caused by a side force is cut off by the supplementary groove 24. Thus the wearing rate of a part of the tread 16 on the center side is lowered so that the life cycle against wear is improved. Also, the shoulder side end 24A of the supplementary groove 24 is arranged in a position coinciding with the split position between the split mold 26A and 26B upon operating a vulcanization process, so that the level difference resulting from an arrangement of the split position between the split mold 26A and 26B can be prevented. |
