| 摘要 |
PROBLEM TO BE SOLVED: To make compatible low-RR performance and the friction resistance of a rubber chafer, in a narrow-width large-diameter radial tire.SOLUTION: A pneumatic radial tire for a passenger car comprises a carcass composed of a carcass ply 4 of a radial arrangement cord which straddles a pair of bead parts in a toroidal shape, and a rubber chafer 6. In the case that a tire cross section width SW is smaller than 165 (mm) when the tire is assembled into a rim, and internal pressure is set at 250 kPa or higher, a ratio SW/OD of the tire cross section width SW and an outside diameter OD (mm) is not larger than 0.26, and in the case that the tire cross section width SW is not smaller than 165 (mm), the tire cross section width SW and the outside diameter OD satisfy a relational equation 2.135×SW+282.3≤OD, a 100%-modulus of the rubber chafer is not smaller than 2.0 MPa, and a viscoelastic characteristic is 6.0 MPa≤E', and tanδ≤0.25. |
