# Patent

## Title
Educational board game and method of playing the same

## Abstract

As is apparent from Examples 1 to 4, the ionomer resin which blends three ionomer resins in a specific amount ratio exhibits excellent physical properties for golf balls. The specific amount ratio of the present invention is existent within the diagonal line portion in FIG. 1. If the amount ratios are outside of the diagonal line portion, initial velocity is deteriorated. In the diagonal line portion, three ionomer resins optimize their functions, but in the outside of the diagonal line portion, physical properties of each ionomer resin come to the front.

## Background
## Claims

1. 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 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, 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 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;

2. The golf ball according to claim 1 wherein said ionomer resin A has a melt index of 0.8 to 3.0.

3. The golf ball according to claim 1 wherein said ionomer resin B has carboxyl groups neutralized with zinc or magnesium ion in an amount of 50 to 60 mol %.

4. The golf ball according to claim 1 wherein said ionomer resin B is prepared by treating the sodium neutralized ionomer resin to remove sodium ions and then mixing the zinc or magnesium ion sources.

5. The golf ball according to claim 4 wherein said zinc ion sources are zinc carbonate, zinc acetate or the like.

6. The golf ball according to claim 4 wherein said magnesium ion sources are magnesium hydroxide, magnesium oxide or magnesium acetate.

7. The golf ball according to claim 1 wherein said ionomer resin B has a melt index of 0.8 to 2.0.

8. The golf ball according to claim 1 wherein said ionomer resin C is prepared by further neutralizing with zinc or magnesium ion an ionomer resin which has been neutralized with sodium ion in an amount of 10 to 50 mol % based on the total amount of the carboxyl group of the ionomer resin.

9. The golf ball according to claim 1 wherein said ionomer resin C has a melt index of 0.5 to 1.5.

10. The golf ball according to claim 1 wherein the mixing of the ionomer resins A, B and C is carried out using an extruder.

11. The golf ball according to claim 2 wherein said ionomer resin B has carboxyl groups neutralized with zinc or magnesium ion in an amount of 50 to 60 mol %.

12. The golf ball according to claim 2, wherein said ionomer resin B has a melt index of 0.8 to 2.0.

13. The golf ball according to claim 11 wherein said ionomer resin C is prepared by further neutralizing with zinc or magnesium ion an ionomer resin which has been neutralized with sodium ion in an amount of 10 to 50 mol % based on the total amount of the carboxyl groups of the ionomer resin.

14. The golf ball according to claim 11 wherein said ionomer resin C has a melt index of 0.5 to 1.5.

15. The golf ball according to claim 12 wherein said ionomer resin C is prepared by further neutralizing with zinc or magnesium ion an ionomer resin which has been neutralized with sodium ion in an amount of 10 to 50 mol % based on the total amount of the carboxyl groups of the ionomer resin.

16. The golf ball according to claim 12 wherein said ionomer resin C has a melt index of 0.5 to 1.5.

17. The golf ball according to claim 1 wherein said cover has a melt index of 1.0 to 2.5.