| 摘要 |
PURPOSE: To provide a tire which can attain weight reduction, low fuel consumption and high durability by forming it out of polybutadiene foam rubber containing syndiotactic crystal, and orienting the syndiotactic crystal in the peripheral direction of a tire. CONSTITUTION: This side wall is composed of rubber composition which contains 30-70 pts.wt. of polybutadiene containing 2.5-15wt.% of 1, 2-syndiotactic- polybutadienne crystal per 100 pts.wt. rubber, and is constituted of foam rubber which contains independent foams of average diameter 20-80μm, and whose foaming factor (Vs) is 5-20%. 1,2-syndiotactic-polybutadiene crystal is oriented in the peripheral direction of a tire. It is thus possible to decrease rolling resistance with durability maintained, thus providing a tire which can attain weight reduction, low fuel consumption and high durability. |
