Golf ball cores comprising blends of polybutadiene rubbers

• US 6,982,301 B1
• Filed: 08/12/2003
• Issued: 01/03/2006
• Est. Priority Date: 06/07/2002
• Status: Expired due to Term

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Bulpett, David A., Sullivan, Michael J., Ladd, Derek A., Voorheis, Peter R., Pasqua, Samuel A. Jr.
• Primary Examiner(s): Buttner, David J.
• Application Number:
  US10/639,116
• Time in Patent Office: 875 Days
• Field of Search: 525/193, 525/236, 525/274, 473/371, 473/372, 473/373
• US Class Current: 525/193
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: A63B 37/0045 Thickness
• CPC Class Codes: A63B 37/0047 Density; Specific gravity
• CPC Class Codes: A63B 37/0052 Liquid cores
• CPC Class Codes: A63B 37/0054 Substantially rigid, e.g. metal
• CPC Class Codes: A63B 37/0056 Hollow; Gas-filled
• CPC Class Codes: A63B 37/0064 Diameter
• CPC Class Codes: A63B 37/0093 Moisture vapour transmission rate [MVTR]
• CPC Class Codes: A63B 37/06 Elastic cores

Abstract

A golf ball comprising a solid core and a cover disposed about the core, wherein the core is formed from a polybutadiene blend comprising a) a first polybutadiene having a first Mooney viscosity between about 50 and about 150, and b) a second polybutadiene having a second Mooney viscosity between about 30 and about 100, wherein the first Mooney viscosity is greater than the second Mooney viscosity, and wherein the blend has a greater weight percentage of the first polybutadiene than that of the second polybutadiene.

Claims

1. A golf ball comprising a solid core and a cover disposed about the core, wherein the core is formed from a polybutadiene blend comprising:

a) a first polybutadiene formed with a cobalt or nickel catalyst having a first Mooney viscosity between about 50 and about 150; and

b) a second polybutadiene formed with a lanthanide series catalyst having a second Mooney viscosity between about 30 and about 100;

wherein the first Mooney viscosity is greater than the second Mooney viscosity, and wherein the blend has a greater weight percentage of the first polybutadiene than that of the second polybutadiene, and wherein the core comprises a reactive co-agent in an amount less than about 5 phr by weight of the polybutadiene blend.

2. The golf ball of claim 1, wherein a ratio of weight percentage between the first and second polybutadiene is at least about 51:

49.

3. The golf ball of claim 2, wherein the ratio of weight percentage is at least about 60:

40.

4. The golf ball of claim 3, wherein the ratio of weight percentage is at least about 75:

25.

5. The golf ball of claim 1, wherein the lanthanide series catalyst is a neodymium catalyst.

6. The golf ball of claim 1, wherein the first Mooney viscosity is between about 60 and about 150, and the second Mooney viscosity is between about 35 and about 90.

7. The golf ball of claim 6, wherein the first Mooney viscosity is between about 70 and about 130, and the second Mooney viscosity is between about 45 and about 80.

8. The golf ball of claim 1, wherein the first polybutadiene has a number average molecular weight between about 150,000 and about 250,000 and a polydispersity between about 1.50 and about 3.50.

9. The golf ball of claim 1, wherein the second polybutadiene has a number average molecular weight between about 150,000 and about 275,000 and a polydispersity between about 1.25 and about 2.75.

10. The golf ball of claim 1, wherein the polybutadiene blend has a cis-1,4 content of at least about 80% in the polymer chains.

11. The golf ball of claim 1, wherein the polybutadiene blend comprises at least about 65% by weight of the core.

12. The golf ball of claim 11, wherein the polybutadiene blend comprises between about 70% and about 85% by weight of the core.

13. The golf ball of claim 1, wherein the amount of the reactive co-agent is about 0 phr by weight of the polybutadiene blend.

14. The golf ball of claim 1, wherein the reactive co-agent comprises a salt of an unsaturated carboxylic acid having about 3 to 8 carbon atoms;

an unsaturated vinyl compound;

a polyfunctional monomer;

phenylene bismaleimide;

or a mixture thereof.

15. The golf ball of claim 1, wherein the core comprises one or more materials selected from the group consisting of natural rubber;

balata;

gutta-percha;

synthetic polyisoprene;

styrene-butadiene rubber;

styrene-propylene-diene rubber;

chloroprene rubber;

acrylonitrile rubber;

acrylonitrile-butadiene rubber;

ethylene-propylene rubber;

ethylene-propylene-diene terpolymer; and

mixtures thereof.

16. The golf ball of claim 1, wherein the core has an outer diameter of about 1.40 inches to about 1.65 inches.

17. The golf ball of claim 1, wherein the cover has a thickness of about 0.01 inches to about 0.20 inches.

18. The golf ball of claim 1, wherein the cover comprises two or more layers.

19. The golf ball of claim 1, wherein the core comprises a center and at least one outer core layer, and wherein at least the center or the outer core layer comprises the polybutadiene blend.