Pneumatic radial tires for passenger cars having a low rolling resistance

摘要

A pneumatic radial tire for passenger cars having a low rolling resistance is disclosed. The radial tire comprises a body reinforcement including a toroidal carcass composed of radially arranged cords and a belt superimposed about the carcass and consisting of plural rubberized plies each containing cords arranged at 60-80 with respect to the radial plane of the tire, which cords of said plies being crossed with each other, and a bead reinforcement wherein the carcass is wound around a bead core to form a turnup portion, thread and sidewall rubbers covering these reinforcements. In the radial tire, a super-hard bead filler rubber is arranged at a region extending from the bead core to the middle part of the side portion, and a base rubber having a low loss modulus and a high resilience is arranged on at least both side edge parts of the belt at a volume ratio in the coating rubber for tread portion of 0.1-0.5.