| 摘要 |
PROBLEM TO BE SOLVED: To provide a pneumatic tire capable of restraining development into a belt of a crack caused at the groove bottom of a lug groove arranged in a tread. SOLUTION: When the crack is caused at the groove bottom 11 of the lug groove 9, the belt 4 is contracted and restored in the tread width direction every time when a tire 1 repeats grounding and separation to a road surface by rotating, and though this groove bottom crack gradually develops toward the belt 4 when its deforming behavior of the belt 4 is transmitted to the lug groove bottom 11, by arranging a soft rubber layer 12 easily deformable more than tread rubber 5 in a position corresponding to at least the groove bottom 11 of the lug groove 9 between the tread rubber 5 and the belt 4, this soft rubber layer 12 reduces a transmission quantity to the lug groove bottom 11 of a deformation quantity of the belt 4, so that the development of the groove bottom crack can be restrained. COPYRIGHT: (C)2010,JPO&INPIT |
