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US 4,984,804 AGranted
Golf ball
AssigneeSumitomo Rubber Industries, Ltd.
InventorsMikio Yamada, Yoshinobu Nakamura
Life of this patent
Estimating the term…
Abstract
The present invention provides a golf ball covering with a special ionomer resin mixture having improved properties. The special ionomer resin mixture has a melt index of 0.5 to 3.0 and a Shore D hardness of at least 65, and is prepared by mixing three ionomer resins in specific amount ratios.
Claims17
A golf ball comprising a core and a cover covering said core, wherein said cover has a melt index of 0.5 to 3.0 and a Shore D hardness of at least 65, and is prepared by mixing
- (A) an ionomer resin having a melt index of 0.5 to 5.0 and a Shore D hardness of at least 65, prepared from an ethylene-methacrylic acid copolymer containing 10 to 20% by weight of methacrylic acid with the balance ethylene of which 20 to 70 mol % of the carboxyl groups is neutralized with sodium ions,
- (B) an ionomer resin having a melt index of 0.5 to 3.0 and a Shore D harness of at least 65, prepared from said eithylene-methacrylic acid copolymer of which 40 to 70 mol % of the carboxyl groups is neutralized with zinc ions or magnesium ions, and
- (C) an ionomer resin having a melt index of 0.1 to 2.0 and a Shore D hardness of at least 65, prepared from said ethylene-methacrylic acid copolymer of which 10 to 50 mol % of the carboxyl groups is neutralized with sodium ions and 10 to 50 mol % of the carboxyl groups is neutralized with zinc ions or magnesium ions,
- in an amount ratio sufficient to meet the following relationships;
- 3.ltoreq. A .ltoreq.60
- 10 .ltoreq.B .ltoreq.50
- 5 .ltoreq.C .ltoreq.40
- A +B +C=100(% by weight).
5 more elements
Dependencies are inferred from the claim text.