Patent ID: 9687697
Date: 2017-06-27
CPC Classifications: A63B

Claim:
1. A multi-piece golf ball comprising a center and n (n is a natural number of 4 or more) envelope layers covering the center, wherein material hardness of the envelope layers satisfies H2<H0<Hn−1; the envelope layers formed in order from the center side are referred to as a first envelope layer, a second envelope layer, . . . an n−1th envelope layer and an nth envelope layer (the outmost layer), respectively, and H0 is a material hardness (Shore D hardness) of the center, and H1, H2 . . . Hn−1 and Hn are material hardness (Shore D hardness) of the first envelope layer, the second envelope layer, . . . the n−1th envelope layer and the nth envelope layer (the outmost layer), respectively; the center is formed from a thermoplastic resin composition; the second envelope layer is formed from a thermoplastic resin composition or a rubber composition; the second envelope layer has a lowest hardness (Shore D hardness) among the envelope layers from the first envelope layer to the n−1th envelope layer; a hardness difference ((Hn−1)−H0) between the material hardness Hn−1 (Shore D hardness) of the n−1th envelope layer and the material hardness H0 (Shore D hardness) of the center ranges from 36 to 75; and the second envelope layer has material hardness H2 (Shore D hardness) ranging from 3 to 35.