Patent ID: 9233279
Filing Date: 2016-01-12
CPC Classification: A63B

Claim Text:
1. 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 core is formed primarily of a thermoplastic resin, has a shore D center hardness of from 30 to 46 and has a deflection, when compressed under a final load of 1,275 N (130 kgf) from an initial load of 98 N (10 kgf), of from 3.3 to 10 mm, has a diameter of from 20 to 30 mm, the envelope layer is formed of a rubber composition containing primarily a rubber material and has a thickness of from 3 to 10 mm, the intermediate layer is formed of a resin composition containing primarily an ionomer which has an unsaturated carboxylic acid content (acid content) of at least 16 wt %, and the cover is formed of a resin composition containing primarily a urethane; wherein the intermediate layer has a specific gravity of from 0.90 to 0.98, and the core, the envelope layer and the intermediate layer have specific gravities which satisfy the condition: core specific gravity<envelope layer specific gravity>intermediate layer specific gravity; and wherein the core, the envelope layer, the intermediate layer and the cover have Shore D surface hardnesses which satisfy the condition: core surface hardness<envelope layer surface hardness<intermediate layer surface hardness>cover surface hardness.