| 摘要 |
PROBLEM TO BE SOLVED: To provide a mold for a golf ball capable of giving a golf ball having an excellent aerodynamic characteristic and facilitating the manufacture of golf balls. SOLUTION: This mold for golf ball is formed of an upper mold 1 and a lower mold 3. A cavity surface 5 of the upper mold 1 and the lower mold 3 are provided with multiple projections 7 to form dimples. A mating surface between the upper mold 1 and the lower mold 3 is formed into an irregular surface. In each upper mold 1 and lower mold 3, the number of projecting part and recessed part is set at 3-5. In each projecting part, 2-8 projections 7 exist in the first line from the mating surface. In each projecting part, at least one of the projections 7 of the first line from the mating surface satisfies a following mathematical expression I. In this mathematical expression I, R means a radius of the corresponding projection 7, and L means a straight distance in the vertical direction between the center of the corresponding projection 7 and the mating surface. R×0.8<=L<=R×1.2...(I).
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