| 摘要 |
PURPOSE:To effectively suppress breakage of sipe while ice snow performance is maintained, in a tyre wherein foamed rubber is used for a tread part. CONSTITUTION:An inside rubber layer 3B having high hardness is arranged on the inner side of an outside rubber layer 3A formed of foamed rubber, and the groove bottom (an inner end 15a in a radial direction) of sipe 15 is positioned in the inside rubber layer 3B. In this case, the occurrence of a dynamic strain in the inside rubber layer 3B is reduced and rigidity and strength are high, whereby the generation of a rupture force at the groove bottom of the sipe 15 is reduced and breakage of the sipe is effectively suppressed. |
