Patent ID: 8840493
Filing Date: 2014-09-23
Classification: A63B

Abstract:
1. A golf ball comprising a core, a surrounding layer situated on the external side of the core, a mid layer situated on the external side of the surrounding layer, and a cover situated on the external side of the mid layer, the mid layer having a thickness Tm of 0.1 mm or greater and 1.2 mm or less, the ratio (Tc/Tm) of the thickness Tc of the cover to the thickness Tm of the mid layer being no greater than 0.38, the cover having a Shore D hardness Hc of no greater than 35, the Shore D hardness Hm of the mid layer being greater than the Shore D hardness Hc of the cover, the base material of the mid layer is a polyurethane, the difference (Hs −Hm) between the hardness Hs and the hardness Hm is 5 or greater and 40 or less, the difference (Hm −Hc) between the hardness Hm and the hardness Hc is 3 or greater and 30 or less, the difference (Hs −Hc) between the hardness Hs and the hardness Hc is 25 or greater and 60 or less, and an amount of compressive deformation Dm of a spherical body composed of the core, the surrounding layer and the mid layer is 1.8 mm or greater and 3.8 mm or less.