US 9,174,093 B2 · Multi-piece solid golf ball

Abstract

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 made primarily of a rubber material and has a diameter of at least 31 mm, the envelope layer and intermediate layer are each made primarily of the same or different resin materials and the cover is made primarily of polyurethane; intermediate layer and cover have an optimized thickness relationship; the core, envelope layer, intermediate layer and cover have optimized hardness relationships; and the core surface and core center have a large hardness difference therebetween. The golf ball has excellent flight performance and controllability acceptable to professionals and other skilled golfers, while also having excellent durability to cracking upon repeated impact and excellent scuff resistance.

Claims19

Dependent claims

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 made primarily of a rubber material and has a diameter of at least 31 mm, the envelope layer and intermediate layer are each made primarily of the same or different resin materials and the cover is made primarily of polyurethane, the material hardness of the cover is softer than the material hardness of the intermediate layer by the hardness difference of at least 1 but less than 40 in Durometer D hardness units;

the envelope layer and intermediate layer have thicknesses which satisfy the relationship
intermediate layer thickness≦envelope layer thickness;
and the core, envelope layer, intermediate layer and cover have hardness relationships which satisfy the following three conditions:
(1) core surface hardness≦envelope layer surface hardness,
(2) cover material hardness<intermediate layer material hardness, and
(3) core surface hardness−core center hardness (JIS-C)≧11.

3 more elements

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 made primarily of a rubber material and has a diameter of at least 31 mm, the envelope layer and intermediate layer are each made primarily of the same or different resin materials and the cover is made primarily of polyurethane, the material hardness of the cover is softer than the material hardness of the intermediate layer by the hardness difference of at least 1 but less than 40 in Durometer D hardness units;

the envelope layer and intermediate layer have thicknesses which satisfy the relationship
intermediate layer thickness≦envelope layer thickness;
and the core, envelope layer, intermediate layer and cover have hardness relationships which satisfy the following three conditions:
(2) cover material hardness<intermediate layer material hardness, and
(3) core surface hardness−core center hardness (JIS-C)≧11.

2 more elements

Dependencies are inferred from the claim text.

Multi-piece solid golf ball

Life of this patent

Multi-piece solid golf ball

Life of this patent

Abstract

Claims19