GOLF BALL AND METHOD OF MANUFACTURE

摘要

In a golf ball having a core and a cover, the core is formed of a rubber composition, has center and surface portions which are unfoamed regions and has an intermediate portion containing a foamed region. The core is produced by charging the rubber composition, which contains a blowing agent, into a first curing mold and curing under given conditions, then removing the molded rubber material in a semi-cured state from the first mold, transferring the semi-cured material to a second curing mold and curing under given conditions. The foamed region of the core deforms by a certain degree at the time of impact, decreasing the radius of gyration of the ball and enabling a lower spin rate to be achieved. The decrease in resilience due to expansion of the molded material can be held to a minimum.

主权项

1. A golf ball comprising a core and a cover of one or more layer encasing the core, wherein the core is formed of a rubber composition comprising a base rubber, a co-crosslinking agent, an organic peroxide and a blowing agent, has a center portion and a surface portion that are unfoamed regions, and has an intermediate portion containing a foamed region.