Patent ID: 7951015

Claim:
A multilayer golf ball comprising: a core comprising at least three core layers comprising a center, an inner core layer, and an outer core layer; at least one cover layer; and at least one moisture vapor barrier layer comprising a locally curable material selected from the group comprising butyl rubber, polysulfide rubber, a single-pack castable polymer comprising uretdione, a single-pack castable polymer comprising isocyanate and an amine, and a single-pack castable polymer comprising isocyanate and a polyol intermediate between the outer core layer and the at least one cover layer and exhibiting a moisture vapor transmission rate less than that of the cover layer; wherein the center, the inner core layer, and the outer core layer exhibit a hardness gradient, wherein the hardness gradient increases toward the at least one intermediate vapor barrier layer, and wherein: the center hardness is no more than about 50 Shore C; the inner core hardness is greater than about 50 Shore C; the outer core hardness is greater than about 65 Shore C; or a combination thereof.