Patent ID: 7390273

Claim:
A golf ball which comprises a core, a cover covering this core and numerous dimples formed on the surface of the cover, wherein the cover has a thickness of less than 3.0 mm and a hardness H 4 of equal to or greater than 90, a difference (H 2 −H 1 ) between a surface hardness H 2 of the core and a central hardness H 1 of the core is 10 or greater and 25 or less, a difference (H 4 −H 1 ) between a hardness H 4 of the cover and the central hardness H 1 of the core is equal to or greater than 25, a difference (H 4 −H 2 ) between the hardness H 4 of the cover and the surface hardness H 2 of the core is 10 or greater and 20 or less, provided that mean diameter of all dimples is Da, a ratio (N1/N) of a number N1 of adjacent dimple pairs having a pitch of (Da/4) or less to total number N of the dimples is equal to or greater than 2.70, and a ratio (N2/N1) of number N2 of adjacent dimple pairs having a pitch of (Da/20) or less to the number N1 is equal to or greater than 0.50.