| 摘要 |
PURPOSE:To improve wear resistance, slip resistance and traction performance, by expansively forming the bottom part of recessed grooves in a tread to an oval shape. CONSTITUTION:Recessed grooves 1 and thin notches 2 are formed on the surface of a tire. This groove 1 is more expansively formed toward the bottom part. A sectional width of the groove 1 is formed to 60-80% its depth while a recessed groove width (b) in a tread level is formed to 30-80% the maximum groove width B of a groove bottom. Then notches of the tread level are placed at least in the vicinity of the groove, and depth E of the notch is arranged to 50-80% depth A of the tread recessed groove, further the density of the notches is formed to 2% or less the tread level. In the above constitution, a tire life can be improved, especially for initial wear, remarkably extended while maintaining anti-slip performance and traction performance. |
