CPC A63B 37/0076 (2013.01) [A63B 37/008 (2013.01); A63B 37/0033 (2013.01); A63B 37/0045 (2013.01); A63B 37/0063 (2013.01); A63B 37/0064 (2013.01); A63B 37/00922 (2020.08)] | 11 Claims |
1. A multi-piece solid golf ball comprising a core, an envelope layer, an intermediate layer and a cover, the core being formed of a rubber composition as one or more layer, the envelope layer being formed of a resin material as one or more layer and the intermediate layer and the cover each being formed of a resin material as a single layer,
wherein
the core has a diameter of from 35.1 to 41.3 mm;
the ratio (core diameter)/(ball diameter) has a value of at least 0.825;
the core has a hardness profile in which, letting Cc be the Shore C hardness at a center of the core, Cc+4 be the Shore C hardness 4 mm outward from the core center, Cm be the Shore C hardness at a midpoint M between the core center and a surface of the core, Cm−4 and Cm+4 be the respective Shore C hardnesses at positions 4.0 mm inward and 4.0 mm outward from the midpoint M, Cs be the Shore C hardness at the core surface and Cs−4 be the Shore C hardness 4 mm inward from the core surface and defining the surface areas A to D as follows
surface area A: ½×4×(Cc+4−Cc)
surface area B: ½×4×(Cm−Cm−4)
surface area C: ½×4×(Cm+4−Cm)
surface area D: ½×4×(Cs−Cs−4),
the ratio (surface area C)/(surface area A) has a value of 0.5 or more and Cs−Cc has a value of 20 or more;
the center hardness of the core, surface hardness of the core, surface hardness of the sphere obtained by encasing the core with the envelope layer (envelope layer-encased sphere), surface hardness of the sphere obtained by encasing the envelope layer-encased sphere with the intermediate layer (intermediate layer-encased sphere) and surface hardness of the ball have Shore C hardness relationships therebetween which satisfy the following conditions:
core surface hardness<surface hardness of envelope layer-encased sphere<surface hardness of intermediate layer-encased sphere>ball surface hardness, and (1)
(surface hardness of envelope layer-encased sphere)−(center hardness of core)≥28; (2)
and the envelope layer, intermediate layer and cover have respective thicknesses which satisfy the following condition:
cover thickness<intermediate layer thickness (3)
cover thickness<envelope layer thickness (4)
envelope layer thickness≥0.8 mm (5).
|