| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To make the shape stability in the of a steel cord securable and improve the durability of a pneumatic radial tire by improving the permeability of rubber into the steel cord by employing one process-strand of a low production cost in the pneumatic radial tire in which the steel cord is used for reinforcing a belt layer. <P>SOLUTION: Four to nine sheath filaments 2 are stranded around a core filament 1 with a laterally long cross section. The core filament 1 is corrugated in small diameter and large diameter directions viewed from the cross section of the core filament 1, and is set so that the corrugation ratios (a dimension of the cross section of the filament / the outer diameter of a corrugated section) in the small diameter direction and the large diameter direction become not less than 1.5 to less than 2.0. The aspect ratio of the cross section of the core filament 1 is set to 0.70 to 0.90, and the corrugation pitch of the core filament 1 in the small and large diameter directions is set smaller than that of the strand of the sheath filament 2. <P>COPYRIGHT: (C)2004,JPO</p> |
