| 摘要 |
PROBLEM TO BE SOLVED: To provide a pneumatic radial tire for maintaining or enhancing road noise performance while reducing rolling resistance in a relatively low speed range when traveling in a city area or the like. SOLUTION: The pneumatic radial tire includes: a pair of right and left beads 1; a carcass ply 2 extending from a crown to both the beads through both sides; one or more layers of belts 3 arranged on the outer side in the radial direction of the crown of the carcass ply 2; and a belt reinforcement layer 4 and a tread arranged on the outer side in the radial direction of the crown of the belts 3. A value S<SB>CL</SB>of the central part 4A and a value S<SB>Sho</SB>of a portion 4B near the belt end in the tire width direction of the dry heat shrinkage ratio at 177°C of a cord of the belt reinforcement layer 4 satisfy a relationship represented by the following inequalities (I) to (III), (I): 0.2≤S<SB>CL</SB>/S<SB>Sho</SB><1.0, (II): 1.3%≤S<SB>Sho</SB>≤6.0%, and (III): 1.0%≤S<SB>CL</SB><6.0%. COPYRIGHT: (C)2011,JPO&INPIT |
