Patent attributes
A mold for a golf ball includes an upper portion (1) and a lower portion (3). A large number of projections (7) for dimple formation are provided on a cavity surface (5) of each of the upper portion (1) and the lower portion (3). A parting surface (8) of the upper portion (1) and the lower portion (3) has a concavo-convex shape. The parting surface (8) includes a first horizontal plane (13), a second horizontal plane (15) and an inclined surface (17). Circumferential central angles φ of the first horizontal plane (13) and the second horizontal plane (15) are 55 degrees or less. A total value Σφ of the circumferential central angles φ is 30 degrees to 330 degrees. An inclination angle α of the inclined surface (17) to a horizontal direction is 10 degrees to 60 degrees. A central angle θ between the horizontal planes (13) and (15) and an equator (E) is 1 degree to 8 degrees. A boundary corner portion of the horizontal planes (13) and (15) and the inclined surface (17) is subjected to rounding.