| 摘要 |
<p>PURPOSE:To improve the durability of a folded-back portion of a pneumatic radial tire in which a carcass layer using aromatic polyamide fiber cord is disposed, by disposing a predetermined hardness upper side bead filler on the outside of a turn-up portion of the carcass layer. CONSTITUTION:An end of a carcass layer 4 is raised from the inside of a tire to the outside around a bead wire 3 and an under side bead filler 6 to form a turn-up portion 4a along a carcass layer body 4b. And outside the turn-up portion 4a is disposed an upper side bead filler 7 having JIS hardness of 75-95. By this constitution, is located the neutral shaft for tire bending near the inside surface of tire in the upper side bead filler 7 so that a compressive force of the turn-up portion 4a to a code can be avoided to prevent breakage of the cord and improve the durability.</p> |
