Patent ID: 7566280

Claim:
A golf ball comprising a ball component made of a material molded under heat from a rubber composition comprising (a) a base rubber which includes a polybutadiene of at least 40% cis-1,4 structure, (b) an unsaturated carboxylic acid and/or a metal salt thereof, (c) an organic peroxide, and (d) a halogenated thiophenol, and/or a metal salt thereof, which is prepared by reacting starting materials in a polar solvent and then washing with water and drying; wherein the polybutadiene has a stress relaxation time (T 80 ), defined as the time in seconds from the moment when rotation is stopped immediately after measurement of the ML 1+4 (100° C.) value (the Mooney viscosity measured at 100° C. in accordance with ASTM D-1646-96) that is required for the ML 1+4 value to decrease 80%, of 5.5 or less.