RUBBER-REINFORCING FIBER, PROCESS FOR PRODUCING THE SAME, AND RUBBER PRODUCT AND PNEUMATIC TIRE EACH MADE WITH THE SAME

The rubber-reinforcing fiber of the present invention is provided with a coating layer of a thickness of 10 ANGSTROM to 40 mu m. The coating layer is formed by dry plating and contains at least one metal and/or metal compound selected from the group consisting of cobalt, zinc, copper, titanium, silver, nickel and compounds of the aforesaid metals. With such a coating layer, the rubber-reinforcing fiber of the present invention forms a firm adhesion to a rubber component and drastically improves the fatigue resistance and durability of a rubber article, particularly, a pneumatic tire.