Patent ID: 8827838

Claim:
A multi-piece solid golf ball comprising a core, an envelope layer encasing the core, an intermediate layer encasing the envelope layer, and a cover which encases the intermediate layer and has formed on a surface thereof a plurality of dimples, wherein the envelope layer has an inner layer and an outer layer; the core is formed primarily of a rubber material; the inner and outer envelope layers, the intermediate layer and the cover are each formed primarily of the same or different resin materials; the inner and outer envelope layers, intermediate layer and cover have thicknesses which satisfy the following conditions (i) and (ii): cover thickness<intermediate layer thickness<(inner envelope layer thickness+outer envelope layer thickness) (i) (cover thickness+intermediate layer thickness)<(inner envelope layer thickness+outer envelope layer thickness); (ii) and inner envelope layer, outer envelope layer, intermediate layer and cover have Shore D hardnesses which satisfy the following condition (iii): inner envelope layer hardness<outer envelope layer hardness<intermediate layer hardness>cover hardness, (iii) and wherein the total thickness of the envelope layer is at least 2.0 mm but not more than 10.0 mm; wherein the core has a deflection (P) when compressed under a final load of 1,275 N (130 kgf) from an initial load of 98 N (10 kgf) of at least 5.7 mm but not more than 12.0 mm, and the ball as a whole has a deflection (Q) when compressed under a final load of 1,275 N (130 kgf) from an initial load of 98 N (10 kgf) of at least 1.8 mm but not more than 4.0 mm, and wherein the value (P)−(Q) is at least 1.8 mm but not more than 10.0 mm; and wherein the value represented by (JIS-C hardness of inner envelope layer surface)−(JIS-C hardness of core surface) in JIS-C hardness units is at least 1 but not more than 20.