| 摘要 |
PROBLEM TO BE SOLVED: To provide a rubber-steel cord composite material capable of maintaining the cord strength after vulcanization without increasing the diameter of a cord in a cord having a double-twisted structure by improving both the breaking strength and the tenacity density of the single cord, and to provide a method for producing the composite material and a pneumatic tire produced by using the same. SOLUTION: The rubber-steel cord composite material contains a steel cord embedded in a rubber. The steel cord has a double-twisted structure obtained by twisting a plurality of filaments 1 to form a strand having a layer-twisted structure, and twisting a plurality of the strands in the form of a layer-twisted structure formed of a core 11 and at least one layer of sheath 12. The circumscribing circles of the outermost sheath strands 12 of the steel cord are made contact with each other between the adjacent strands, and the covering ratio of rubber around the strand layer positioned immediately inside at least the outermost sheath strand 12 is 50% or more. COPYRIGHT: (C)2009,JPO&INPIT |
