| 摘要 |
Provided is a pneumatic tire improved in a performance against the flat spot with a high-speed durability desirably maintained. The pneumatic tire of the present invention includes: a belt reinforcing layer (7) which is disposed on an outer circumferential side of a belt layer (6) buried in a tread portion (1), and which is composed of an organic fiber cord wound in a circumferential direction of the tire. At least 60% of the total count of the organic fiber cord composing the belt reinforcing layer (7) is a polytetramethylene adipamide fiber cord. The creep set strain of the polytetramethylene adipamide fiber cord is 2.5% or less. The twist coefficient K of the polytetramethylene adipamide fiber cord satisfies a condition of 600‰¤K‰¤1700, and is represented by the following formula (1):
where T is the twist number (turn/10 cm) of the cord, and D is the total fineness (dtex) of the cord.
|
