Patent ID: 7829604

Claim:
A golf ball comprising a hot-molded material obtained by vulcanizing a rubber composition made primarily of a base rubber and an unsaturated carboxylic acid or salt thereof, wherein the rubber composition additionally includes a vulcanized rubber powder from which soluble ingredients have been removed by liquid washing for between 10 minutes and 24 hours, wherein the vulcanized rubber powder is a rubber material formulated from cis-1,4-polybutadiene as the base rubber, together with an unsaturated carboxylic acid, and/or an unsaturated carboxylic acid metal salt, the vulcanized rubber powder has a moisture content when added to the base rubber of up to 600 ppm, and the vulcanized rubber powder is dried at between 120 and 160° C. for at least 20 minutes after the vulcanized rubber powder is liquid washed.