| 摘要 |
Golf ball 2 has a center 8 , a mid layer 10 , a cover 6 and dimples 12 . The mid layer 10 includes a styrene block-containing thermoplastic elastomer having a material hardness of less than 10, and an ethylene-(meth)acrylic acid copolymer-based ionomer resin having a material hardness of 50 or greater and 70 or less. This mid layer 10 has a hardness equal to or less than 50, and a thickness of equal to or less than 1.6 mm. The dimple has: a first side wall face 18 that has a curvature radius R 1 which is equal to or greater than a phantom curvature radius Rx; a second side wall face 20 that is positioned to the bottom side than the first side wall 18 face and has a curvature radius R 2 which is smaller than the phantom curvature radius Rx; and a bottom face 22 that is positioned to the bottom side than the second side wall face 20 and has a curvature radius R 3 which is equal to or greater than the phantom curvature radius Rx.
|
