Abstract: A steel cord composed of four material wires of the same diameter twisted together, of which two material wires are stuck together and intertwisted at the center and each of the other two material wires is arranged on both sides of the former two material wires with a certain space left between the former and the latter. The latter two material wires are twisted about the former two material wires in the same twist direction and at the same pitch as the former two material wires into a steel cord. The steel cord thus composed facilitates infiltration of a rubber compound into the central part of the steel cord, ensures perfect adhesion between the rubber compound and the steel cord, checks elongation under a very low load, stabilizes twist construction in the lengthwise direction and improves an anti-fatigue characteristic.

Abstract: A steel cord having a basic construction constituted by a group of at least two wires of the same diameter twisted together and a single wire or a bundle of a plurality of parallel wires are intertwisted. This steel cord provides better adhesion between a rubber compound and the steel cord because of better infiltration of the rubber compound into a central cavity formed by adjoining steel cords and also better elastic force in the lengthwise direction of the cord.