| 摘要 |
PURPOSE:To prevent a shoulder rib from getting one-sided wear, by forming a shoulder end side zone of the outermost side rib with low abrasive resisting rubber, in case of a tire whose tread is divided into at least three ribs by least two pieces of a circumferential main groove. CONSTITUTION:In case of a radial-ply tire whose tread 1 is divided into at least three pieces of ribs 3 and 4 exdending in the circumferential direction by two broad circumferential main grooves 2 exdending in an almost circumferential direction of the tire tread 1, rubber in a zone 6 at the side of a shoulder end 3 of the shoulder rib 3 is formed from low abrasive resisting rubber A as compared with rubber B in a tread zone 7. Abrasion resistance in the rubber A, if possible, should be below 90% of abrasive resistance in the rubber B, especially to be 20-80%. And, in tread volumes partitioned off by a surface ranging from a surface 1a of the tread 1 to a bottom surface 2a of the circumferential main groove 2 and a tire equatorial surface C, a volume ratio of the rubber A should be set to a range of 1-30%, especially selected within the range of 3-20%. |
