Perimeter weighted golf ball

• US 6,908,402 B2
• Filed: 09/08/2003
• Issued: 06/21/2005
• Est. Priority Date: 03/23/2001
• Status: Expired due to Term

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Voorheis, Peter R., Sullivan, Michael J, Ladd, Derek A
• Primary Examiner(s): Wong, Steven
• Assistant Examiner(s): HUNTER, ALVIN A
• Application Number:
  US10/658,448
• Publication Number:
  US 20040048692A1
• Time in Patent Office: 652 Days
• Field of Search: 473351-377
• US Class Current: 473/376
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0043 Hardness
• CPC Class Codes: A63B 37/0045 Thickness
• CPC Class Codes: A63B 37/0047 Density; Specific gravity
• CPC Class Codes: A63B 37/0051 Materials other than polybutadienes; Constructional details
• CPC Class Codes: A63B 37/0054 Substantially rigid, e.g. metal
• CPC Class Codes: A63B 37/0064 Diameter
• CPC Class Codes: A63B 37/0065 Deflection or compression
• CPC Class Codes: A63B 37/02 Special cores balls with finger holes A63B37/0001, golf ball cores A63B37/005
• CPC Class Codes: A63B 37/06 Elastic cores

Abstract

A perimeter weighted golf ball with a low compression core is provided. The core preferably comprises a diene polymer that has low cross-link density or not cross-linked with a reactive co-agent. This core has low compression and low specific gravity. The low specific gravity core is encased within a thin dense layer positioned outside of the centroid radius to provide the ball with a high moment of inertia. The same core can be encased within a plurality of intermediate layers having either increasing hardness or decreasing hardness to provide selective golf balls for either low swing speed players or advanced players. Alternatively, a thin layer of diene polymer highly cross-linked with reactive a co-agent may be incorporated into the ball to increase the hardness of the ball.

Claims

1. A golf ball comprising:

a core having a Shore C hardness of about 70 or less, the core comprising at least a core layer comprising;

an elastomeric composition,

a reactive co-agent present by less than about 10 phr by weight of the elastomeric composition, and

a cross-linking agent;

at least a first intermediate layer encasing the core, the first intermediate layer having a Shore C hardness of about 70 to about 75; and

a cover encasing the first intermediate layer, the cover having a Shore C hardness of about 60 or less.

2. The golf ball of claim 1, wherein the elastomeric composition comprises a diene polymer.

3. The golf ball of claim 2, wherein the cross-linking agent is a peroxide.

4. The golf ball of claim 3, wherein the diene polymer is a polybutadiene.

5. The golf ball of claim 2, wherein the cross-linking agent is sulfur.

6. The golf ball of claim 5, wherein the diene polymer is an ethylene-propylene-diene polymer.

7. The golf ball of claim 6, wherein the ethylene-propylene-diene polymer comprises about 70% to about 90% ethylene.

8. The golf ball of claim 7, wherein the ethylene-propylene-diene polymer further comprises about 1% to about 5% ethylidene-2-norborene.

9. The golf ball of claim 1, wherein the elastomeric composition comprises a material selected from a group consisting of metallocene catalyzed polymers, poly(styrene-butadiene-styrene), SEBS, SEPS block polymers, styrene-ethylene block copolymers, and polar group grafted or copolymerized polymers.

10. The golf ball of claim 1, wherein the reactive co-agent is present by less than about 5 phr.

11. The golf ball of claim 1, wherein the reactive co-agent comprises a metal salt of diacrylate, dimethacrylate, or monomethacrylate, or a non-metallic oligomer.

12. The golf ball of claim 11, wherein the metal is selected from zinc, magnesium, calcium, barium, tin, aluminum, lithium, sodium, potassium, iron, zirconium, and bismuth.

13. The golf ball of claim 1, wherein the core further comprises an innermost core encased by the core layer.

14. The golf ball of claim 13, wherein the innermost core comprises a diene polymer and about 10 phr to about 50 phr of a reactive co-agent.

15. The golf ball of claim 13, wherein the innermost core comprises a diene polymer and at least about 50 phr of a reactive co-agent.

16. The golf ball of claim 1, wherein the golf ball farther comprises a second intermediate layer encasing the first intermediate layer, the second intermediate layer being harder than the first intermediate layer, and having a Shore C hardness of about 72 to about 77.

17. The golf ball of claim 16, wherein the golf ball further comprises a third intermediate layer encasing the second intermediate layer, the third intermediate layer being harder than the second intermediate layer, and having a Shore C hardness of about 75 to about 80.

18. The golf ball of claim 17, wherein the first, second, and third intermediate layers each has a thickness of less than about 2.54 mm.

19. The golf ball of claim 17, wherein the first, second, and third intermediate layers each has a thickness of less than about 1.27 mm.

20. The golf ball of claim 17, wherein the first, second, and third intermediate layers each has a thickness of about 0.76 mm to about 1.27 mm.

21. The golf ball of claim 1, wherein the core has a diameter of about 31.75 mm to about 40.64 mm.

22. A golf ball comprising:

a core having a Shore C hardness of about 70 or less, the core comprising at least a core a core layer comprising;

an elastomeric composition,

about 0 phr of reactive co-agent by weight of the elastomeric composition, and

a cross-linking agent;

at least a first intermediate layer encasing the core, the first intermediate layer having a Shore C hardness of about 70 to about 75; and

a cover encasing the first intermediate layer, the cover having a Shore C hardness of about 60 or less.