Patent ID: 6943208

Claim:
A solid golf ball comprising a solid core formed using a molded and vulcanized product of a rubber composition as a constituent component, the rubber composition comprising 100 parts by weight of a base rubber composed primarily of a polybutadiene containing at least 60% by weight of cis-1,4-bond, having a Mooney viscosity (ML 1+4 (100° C.)) of at least 30, and synthesized using a rare-earth catalyst, 15 to 50 parts by weight of an unsaturated carboxylic acid and/or a metal salt thereof, at least 2 parts by weight of a processing aid having a melting point of 60 to 115° C., and at least two organic peroxides including an organic peroxide having the shortest half-life at 155° C. designated (a) and another organic peroxide having the longest half-life at 155° C. designated (b), a ratio of half-lives (b t /a t ) being at least 7 and up to 20 wherein a t is the half-life of (a) and b t is the half-life of (b), a total content of the organic peroxides being 0.1 to 0.9 part by weight per 100 parts by weight of said base rubber, and an organosulfur compound in an amount of 0.2 to 5 parts by weight per 100 parts by weight of the base rubber, wherein the polybutadiene has a polydispersity index Mw/Mn of 2.0 to 8.0 wherein Mw is a weight average molecular weight and Mn is a number average molecular weight, wherein the processing aid comprises a mixture of compounds of higher fatty acid metal salts represented by RCOOM, wherein the number of carbon atoms in R is at least 1 and up to 31 and the mixture has the melting range of 60 to 115° C., and wherein the solid core has a deflection of 2.0 to 6.0 mm under an applied load of 100 kg.