Patent ID: 7927235

Claim:
A method of making a golf ball comprising a core having a center and an intermediate layer formed on the center, and a cover covering the core, the intermediate layer having at least two layers comprising an outermost layer and a second layer adjacent to the underside of the outermost layer, and the cover has many dimples formed in the surface thereof, the method comprising the steps of: (a) forming a spherical center, (b) (i) forming the second layer of the intermediate layer on the center by using two core intermediate half molds having a semi-spherical cavity to form a spherical core intermediate, (ii) forming the outermost layer of the intermediate layer on the core intermediate by using two core half molds having a semi-spherical cavity to form a spherical core (c) (i) molding a cover composition, formed from polyurethane-based thermoplastic elastomer, into a semi-spherical half-shell for the cover, (ii) covering the core with two of the half-shells and placing the covered core in a golf ball half mold having a semi-spherical cavity and many projections corresponding to the shape of the dimples in the cavity, (iii) press molding the covered core under heating to mold a golf ball with a cover having a thickness at the bottom of each dimple that differs from the thickness in land portions by no more than 0.2 mm and simultaneously form depressions in the surface of the intermediate layer at positions corresponding to the dimples in the cover, and (d) after cooling, opening the mold to take out a molded golf ball.