| 摘要 |
A steel cord having a three-layer twisted construction consisting of an innermost layer, an intermediate layer, an outermost layer, and a spiral warp and being capable of achieving an improvement in the adhesion force to rubber while reducing the number of processing steps used. In the steel cord, the innermost layer consists of 3 filaments twisted in one of left or right twist directions while having a twist pitch length of 5 to 18 mm; the intermediate layer consists of 8 filaments twisted in the same twist direction as that of the innermost layer while having a twist pitch length of 5 to 18 mm, namely, the same twist pitch length as that of the innermost layer; the outermost layer consists of 13 filaments twisted in a left or right twist direction opposite to those of the innermost and intermediate layers while having a twist pitch length of 10 to 25 mm equal to or more than those of the innermost and intermediate layers; and the spiral wrap consists of a single filament adapted to be wrapped around the outermost layer, thereby preventing the steel cord from being unwound, the filament being twisted in a twisted direction opposite to that of the outermost layer while having a twist pitch length of 3 to 10 mm. Gaps are formed among the filaments of the intermediate and outermost layers. The gaps allow rubber to penetrate easily into the steel cord therethrough. <IMAGE> |
