| 摘要 |
PROBLEM TO BE SOLVED: To provide a lightweight pneumatic radial tire without reducing durability.SOLUTION: A pneumatic radial tire includes: a carcass formed of at least one carcass layers formed between a pair of right and left bead cores in a toroidal shape; a tread part arranged outside a crown area of the carcass in a tire radial direction to form a tread portion; and a belt arranged between the tread part and the crown area of the carcass and formed of at least two belt layers. Each of the first and second belt layers of the belt is obtained by embedding steel cords 10 each comprising a core formed by arranging in parallel two core filaments 11 without twisting and N(2≤N≤4) sheath filaments 12 twisted around the core in coating rubber along a belt width direction in parallel. When a diameter of the core filament 11 is d1, and a diameter of the sheath filament 12 is d2, d1>d2 is satisfied. |
