Patent ID: 6786839
Filing Date: 2004-09-07
Classification: A63B

Abstract:
A multi-piece solid golf ball comprising a solid core, a mantle of at least one layer, and a cover, whereinthe solid core is made of a rubber composition comprising (A) 100 parts by weight of a base rubber that contains 60 to 100 wt % of a polybutadiene of at least 60% cis-1,4 structure and synthesized using a rare-earth catalyst, (B) 0.1 to 0.8 part by weight of an organic peroxide, (C) an unsaturated carboxylic acid or an unsaturated carboxylic acid metal salt or both, (D) an organic sulfur compound and (E) an inorganic filler, has a deflection when subjected to a load of 980 N (100 kgf) of 3.0 to 6.0 mm, and has a diameter of 30 to 40 mm; the mantle of at least one layer is made of a thermoplastic resin composition, has a thickness per layer of 0.5 to 2.0 mm, and includes an outermost layer which is in contact with the cover and has a Shore D hardness of 20 to 60; the cover is made of a material composed of a heated mixture of (F) at least one selected from the group consisting of olefin/unsaturated carboxylic acid copolymers, olefin/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymers, and metal ion neutralization products thereof, (G) a polyurethane elastomer and (H) an organic or inorganic basic compound, has a thickness of 0.5 to 2.5 mm and a Shore D hardness of 50 to 70, and satisfies the condition (Shore D hardness of mantle outermost layer)&lE;(Shore D hardness of cover); and the golf ball has a deflection when subjected to a load of 980 N (100 kgf) of 3.0 to 5.0 mm.