MANUFACTURE OF CORE BODY OF SOLID BALL

摘要

PURPOSE:To prepare a core body having good elasticity nearly equal to the elasticity of the skin layer of a solid ball by kneading cork grains with thermoplastic resin, packing the kneaded material into a mold and then heating and molding it. CONSTITUTION:Cork grains are mixed with thermoplastic resin such as ethylene- vinyl acetate cpolymer etc. The mixture is packed into a mold, heated and molded to manufacture the core body of a solid ball. Since the compressed cork grains are impregnated and packed with thermoplastic resin, the core body obtained is not softened or deformed by batting. The resilience of the core body of the solid ball is reinforced, the core body keeps a semipermanently fixed repulsion, the flying distance and the batting sound of the ball are not deteriorated and manufacturing processes are simplified remarkably.