Method of making a multi-piece solid golf ball
AssigneeSumitomo Rubber Industries, Ltd.
InventorsHiroaki Tanaka, Yoshiyuki Okido, Hideki Sano
Life of this patent
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Abstract
The present invention provides a multi-piece solid golf ball having excellent flight performance and excellent shot feel at the time of hitting, and a method of making the same having good workability. The present invention relates to a multi-piece solid golf ball comprising a core composed of a center and at least one core outer layer formed on the center, and a cover covering the core, wherein the core outer layer is formed from a rubber composition which does not contain zinc salt of unsaturated carboxylic acid.
Claims5
A method of making a multi-piece solid golf ball comprising the steps of:
- (a) molding a rubber composition for a center in a spherical shape to form an unvulcanized center,
- (b) placing a rubber composition for a core outer layer in a mold having a semi-spherical cavity, and either semi-vulcanizing the rubber composition or heating the rubber composition to such a degree that the rubber composition neither semi-vulcanizes nor shrinks between the semi-spherical cavity and a male plug mold to form a semi-vulcanized or unvulcanized semi-spherical half-shell for the core outer layer,
- (c) after removing the male plug mold, mounting the unvulcanized center formed in the step (a) on a concave portion of the semi-vulcanized or unvulcanized semi-spherical half-shell for the core outer layer, and covering the unvulcanized center with a semi-vulcanized or unvulcanized semi-spherical half-shell for the core outer layer separately formed in the same manner as set forth in the step (b) to integrally vulcanize and form a core,
- (d) optionally, repeating the step (c) to form a core having multiple core outer layers, and
- (e) covering the core with a cover, wherein the rubber composition for the core outer layer does not contain a zinc salt of an unsaturated carboxylic acid and the rubber composition for the center contains a zinc salt of an unsaturated carboxylic acid.
Dependencies are inferred from the claim text.