| 摘要 |
To improve high-speed durability of a low-section pneumatic radial tire without producing tire separation at both belt ends and expansion at both tread sidewalls after the tire has been worn to some extent, the tire belt structure (B) disposed between the tire tread (T) and the carcass (10) is composed of two belt layers (20) and a plurality of auxiliary layers (3A, 3B, 3C). The auxiliary layers comprises a first auxiliary layer (30) extending over the belt layers (20) and at least second (31) and third (32) auxiliary layers arranged on both axially outside ends of the tread in such a way that an axially outer end of each of the auxiliary layers extends to near the tread sidewall and an axially inner end of each of the auxiliary layers extends to or beyond under at least an axially outermost circumferential groove formed on the tread in step fashion extending from tread center to tread end or vice versa. Further, these auxiliary layers are formed by winding a ribbon including at least two heat-shrinkable fiber cords (111) coated with a coating rubber (112) on the circumferential surface of the belt-layers - Figure 2(A). |
