| 摘要 |
PROBLEM TO BE SOLVED: To suppress performance decrement in a dry road face and a wet road face even when a sipe is added, so as to keep stability and controllability without being affected by a road face condition. SOLUTION: A block 18 is provided with the closed sipe 20 in its central portion, and partitioned into a central block 18A located in an inner side of the closed sipe 20 and an outer-circumferential block 18 B. An area of a tread face in the central block 18A with respect to the whole tread area of the block 18 is set to 11%, and a depth dimension d of the closed sipe 20 is made equal to a height dimension H of the block 18. Since the central block 18A catches the road face all the time to support a load, floating of the block 18 is suppressed to a small extent and a treading property is excellent even when the outer circumferential block 18B surrounding the central block 18A is tear- deformed. Since the depth dimension of the closed sipe 20 is set to 100% of the height dimension H of the block 18, wet braking performance is enhanced, in particular.
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