Patent ID: 7288031

Claim:
A golf ball, comprising a core, an intermediate layer enclosing the core to form a sphere, and a cover enclosing the intermediate layer, wherein each component has a Shore D hardness, a Deflection amount, an initial velocity (in m/s) and a thickness (in mm), the Deflection amount being defined as an amount of deflection (in mm) under load of a spherical body incurred when the load is increased from an initial value of 98 N (10 kgf) to a final value of 1275 N (130 kgf), and the ball satisfies the following requirements (1) to (4): (1) (Shore D hardness of the cover)−(Shore D hardness of the intermediate layer)>0, (2) (initial velocity of the sphere)−(initial velocity of the core)>0, (3) 0.90≦(Deflection amount of the sphere)/(Deflection amount of the core)≦1.00, and (4) the total of the thickness of the intermediate layer and the thickness of the cover is up to 3.0 mm, wherein said intermediate layer comprises (A) an ionomer resin comprising (a-1) an olefin/unsaturated carboxylic acid binary random copolymer and/or a metal ion neutralized product thereof and (a-2) an olefin/unsaturated carboxylic acid/unsaturated carboxylic acid ester ternary random copolymer and/or a metal ion neutralized product thereof in a weight ratio (a-1)/(a-2) between 100/0 and 0/100, and (B) a non-ionomeric thermoplastic elastomer in a weight ratio A/B between 100/0 and 50/50, wherein said intermediate layer further comprises: (C) 5 to 80 parts by weight of an organic fatty acid and/or a derivative thereof having a molecular weight of 280 to 1,500, and (D) 0.1 to 10 parts by weight of a basic inorganic metal compound capable of neutralizing un-neutralized acid groups in said resin component and component (C), and wherein the ionomer resin (A) and the non-ionomeric thermoplastic elastomer (B) in a weight ratio A/B between 100/0 and 50/50 are 100 parts by weight.