| 摘要 |
PURPOSE:To reduce the rolling resistance and improve the high speed durability by using the cord made of aromatic polyester fiber having a tensile strength over a specific value and tensile modulus over a specific value and applied with twist so that the twist coefficient is set within a specific range, as the reinforcing layer for a tire. CONSTITUTION:The cord made of aromatic polyester fiber having a tensile strength of 15 g/d or more and tensile modulus of 300 g/d or more and applied with twist so that the below-described twist K is set within a range of 800-2800 is used as the reinforcing layer of a radial tire. In this case, K=TD<1/2>. In this case, K is twist coefficient, T is the number of twist (T/10cm), and D is the total denier quantity of the cord. In this tire structure in which a belt layer 5 is arranged in annular form in the direction EE' of the tire periphery on a carcass layer 4 in a tread 1, the above-described cord is used for belt. Therefore, the high speed durability and steering stability, etc., are not deteriorated, and the lightweight tire can be obtained, and the rolling resistance can be reduced.
|
