Patent ID: 9199130
Filing Date: 2015-12-01
Classification: A63B,C08K

Abstract:
1. A golf ball comprising: a spherical core, and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing a base rubber, a co-crosslinking agent, a crosslinking initiator, a filler and 2-naphthalene thiol or a metal salt thereof, the spherical core has a hardness distribution that satisfies B<A≦C, and JIS-C hardness does not decrease in a direction from the spherical core central point toward the spherical core surface, wherein A=(Hardness H5 at a distance of 5 mm from the central point of the spherical core)−(Central hardness HO at the central point of the spherical core); B=(Hardness H12.5 at a distance of 12.5 mm from the central point of the spherical core)−(Hardness H5 at a distance of 5 mm from the central point of the spherical core); C=(Surface hardness Hs at the surface of the spherical core)−(Hardness H12.5 at a distance of 12.5 mm from the central point of the spherical core); and B ranges from 0 to 4 in JIS-C hardness.