| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to reproduce a design value at a high degree, to provide a golf ball with dimples having high-accuracy shapes and sharp edges and to prevent the degradation in the dimple accuracy and the variation in product quality by execution of deburring after dimple formation. SOLUTION: This golf ball has a cover 4 and a coating film 8 formed on this cover 4 and is formed with the dimples on the layer consisting of the cover 4 and the coating film 8. The coating film 8 is formed as a coating film of >=15μm thickness consisting of a material having the heat resistance higher than the heat resistance of the material of the cover 4 and having stretchability. In the production of this golf ball, the working of the dimples is executed at the molding temp. near the m.p. of the cover 4 by compression molding from above the coating film 8 after the formation of the coating film 8. The cover 4 consists of a resin having a softening point of 80 to 150 deg.C, an m.p. of >=180 deg.C and an MI (190 deg.C) of 0.5 to 50. The coating film 8 consists of a resin having a softening point of 80 to 150 deg.C, a.m.p. of >=200 deg.C, a stretching rate of 200 to 900% and a Young's modulus of 15 to 60MPa. |
