Patent ID: 8777780

Claim:
A golf ball comprising a core, an envelope layer positioned outside the core, a mid layer positioned outside the envelope layer, and a cover positioned outside the mid layer, wherein: the difference (H2−H1) between a surface hardness H2 and a central hardness H1 of the core, which are measured with a JIS-C type hardness scale, is equal to or greater than 5 and equal to or less than 35, the mid layer has a thickness Tm less than 1.0 mm; the cover has a thickness Tc of 0.5 mm or less; the envelope layer has a Shore D hardness Hs of 60 or greater, and a principal component of a base material of the envelope layer is an ionomer resin; the mid layer has a Shore D hardness Hm of 50 or greater and 65 or less, and a principal component of a base material of the mid layer is an ionomer resin; the cover has a Shore D hardness Hc less than 40, and a principal component of a base material of the cover is a polyurethane; and the hardness Hs, the hardness Hm and the hardness He satisfy the following mathematical formula: Hs>Hm>Hc.