Patent ID: 6652392
Filing Date: 2003-11-25
Classification: A63B

Abstract:
A multi-piece solid golf ball comprising an elastic solid core and a resin cover enclosing the solid core, the cover being composed of a plurality of layers including an inner layer disposed adjacent to the solid core and an outer layer disposed radially outside the inner layer, the ball being provided on its surface with a multiplicity of dimples, whereinsaid solid core has a hardness corresponding to a deflection of at least 1.1 mm under an applied load of 294 N (30 kgf), said cover inner layer has a Shore D hardness of 45 to 70, said cover outer layer has a Shore D hardness of 35 to 55, further wherein said cover inner layer Shore D hardness is quantified as â€œAâ€  and said cover outer layer Shore D hardness is quantified as â€œBâ€ , and A and B satisfy the relationship: AÃ—B&gE;2300, the multiplicity of dimples being substantially uniformly arranged on the ball surface such that a great circle which does not intersect with the dimples is absent, and wherein the ball receives a spin rate S1 (rpm) in the dry state and a spin rate S2 (rpm) in the wet state when hit with a short iron having a loft of an 8-iron or greater, the percent spin retention given by (S2/S1)Ã—100 is at least 47%.