Two piece molded golf ball

Claim 2

A golf ball comprising a center and a cover, said center comprising a substantially spherical homogeneous molded mass of cis-polybutadiene elastomer highly cross-linked in a three dimensional network with long, flexible cross-links formed from zinc dimethacrylate, said zinc dimethacrylate being present in about 0.046 to 0.038 equivalents per mole of said elastomer, said cover comprising an ionic copolymer of at least 50 mole percent of ethylene and at least about 0.2 mole percent of an alpha, beta-ethylenically unsaturated carboxylic acid selected from the group consisting of methacrylic acid and ethylene acrylic acid wherein about 20%-90% of the carboxylic acid groups are neutralized with a metal.

Claim 3

A golf ball comprising a center and a cover, said center comprising a substantially spherical homogeneous molded mass of a cis-polybutadiene elastomer highly cross-linked into a three dimensional network with long, flexible cross-links formed from zinc dimethacrylate, said zinc dimethacrylate being present in about 0.046 to 0.038 equivalents per mode of said elastomer, said cover comprising an ionic copolymer of at least about 50 mole percent of ethylene and at least about 0.2 mole percent of an alpha, beta-ethylenically unsaturated carboxylic acid selected from the group consisting of methacrylic acid and ethylene acrylic acid wherein about 20%-90% of the carboxylic acid groups are neutralized with a metal, and said center including a filler in up to about 50 parts per 100 parts by weight of said polybutadiene elastomer, said filler being in addition to said zinc dimethacrylate.

Claim 4

A golf ball comprising a center and a cover, said center comprising a substantially spherical homogeneous molded mass of a cis-polybutadiene elastomer highly cross-linked into a three dimensional network with long, flexible cross-links formed from zinc dimethacrylate, said zinc dimethacrylate being present in about 0.046 to 0.038 equivalents per mode of said elastomer, said cover comprising an ionic copolymer of at least about 50 mole percent of ethylene and at least about 0.2 mole percent of an alpha, beta-ethylenically unsaturated carboxylic acid selected from the group consisting of methacrylic acid and ethylene acrylic acid wherein about 20%-90% of the carboxylic acid groups are neutralized with a metal, and said center including a filler in up to about 50 parts per 100 parts by weight of said polybutadiene elastomer, said filler being in addition to said zinc dimethacrylate.

Claim 5

A golf ball according to claim 2 wherein said filler is present in about 20 to 40 parts per 100 parts by weight of said polybutadiene elastomer.

Claim 6

A golf ball according to claim 2, wherein said zinc dimethacrylate is present in about 15 to 35 parts per 100 parts by weight of the polybutadiene.

Claim 7

A golf ball according to claim 4, wherein said center includes about 20 to 40 parts of zinc oxide per 100 parts by weight of said polybutadiene, said cover has a thickness of about 0.1 to 0.2 inch and said ball can be driven at lest 5 yards further than a corresponding one-piece molded golf ball upon application of the same driving force by a driving machine.

Claim 8

A golf ball according to claim 4, wherein said center incluides about 20 to 40 parts of zinc oxide per 100 parts by weight of said polybutadiene, said cover has a thickness of about 0.003 to 0.1 inch and said ball can be driven at least 5 yards further than a corresponding one-piece molded golf ball upon application of the same driving force by a driving machine.

Claim 9

A golf ball according to claim 3 wherein said filler is zinc oxide.

Claim 10

A golf ball according to claim 2 wherein said zinc dimethacrylate is present in the range of 0.06 to 0.25 equivalents per mole of said polybutadiene.

Claim 11

A golf ball comprising a center and a cover, said ball being prepared from a composition comprising 100 parts by weight of cis-polybutadiene and between about 15 to 35 parts by weight of zinc dimethacrylate, said elastomer being highly cross-linked into a three dimensional network with long flexible cross-links formed from said zinc dimethacrylate when said composition is cured in a standard golf ball mold at a temperature between 170° C. and 185° C. for from 30 to 35 minutes, said cover comprising an ionic copolymer of at least about 50 mole % of ethylene and at least about 0.2 mole % of an α,β-ethylenically unsaturated carboxylic acid selected from the group consisting of methacrylic acid and ethylene acrylic acid wherein about 70 to 90% of the carboxylic groups are neutralized with a metal, and said cover having a thickness of between about 0.1 to 0.2 inch, whereby said ball can be driven at least 5 yards further than a corresponding one-piece molded golf ball upon application of the same driving force to said balls by a driving machine.

Claim 12

A golf ball comprising a center and a cover, said ball being prepared from a composition comprising 100 parts by weight of cis-polybutadiene and between about 15 to 35 parts by weight of zinc dimethacrylate, said elastomer being highly cross-linked into a three dimensional network with long flexible cross-links formed from said zinc dimethacrylate when said composition is cured in a standard golf ball mold at a temperature between 170° C. and 185° C. for from 30 to 35 minutes, said cover comprising an ionic copolymer of at least about 50 mole % of ethylene and at least about 0.2 mole % of an α,β-ethylenically unsaturated carboxylic acid selected from the group consisting of methacrylic acid and ethylene acrylic acid wherein about 70 to 90% of the carboxylic groups are neutralized with a metal, and said cover having a thickness of between about 0.1 to 0.2 inch, whereby said ball can be driven at least 5 yards further than a corresponding one-piece molded golf ball upon application of the same driving force to said balls by a driving machine.

Claim 13

A golf ball comprising a center and a cover, said center comprising a substantially spherical homogeneous molded mass of a cis-polybutadiene elastomer highly cross-linked into a three dimensional network with long, flexible cross-links formed from zinc methacrylate, said zinc methacrylate being present in about 0.046 to 0.38 equivalents per mole of said elastomer, said cover comprising an ionic copolymer of at least about 50 mole percent of ethylene and at least about 0.2 mole percent of an alpha, beta-ethylenically unsaturated carboxylic acid selected from the group comprising methacrylic acid and ethylene acrylic acid wherein about 20%-90% of the carboxylic acid groups are neutralized with a metal.

Claim 14

A golf ball comprising a center and a cover, said center comprising a substantially spherical homogeneous molded mass of a cis-polybutadiene elastomer highly cross-linked into a three dimensional network with long, flexible cross-links formed from zinc methacrylate, said zinc methacrylate being present in about 0.046 to 0.38 equivalents per mole of said elastomer, said cover comprising an ionic copolymer of at least about 50 mole percent of ethylene and at least about 0.2 mole percent of an alpha, beta-ethylenically unsaturated carboxylic acid selected from the group comprising methacrylic acid and ethylene acrylic acid wherein about 20%-90% of the carboxylic acid groups are neutralized with a metal.