Multi-layer core golf ball

• US 7,850,549 B2
• Filed: 03/20/2009
• Issued: 12/14/2010
• Est. Priority Date: 01/10/2008
• Status: Active Grant

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Sullivan, Michael J., Ladd, Derek A.
• Primary Examiner(s): GORDEN, RAEANN
• Application Number:
  US12/407,830
• Publication Number:
  US 20090181797A1
• Time in Patent Office: 634 Days
• Field of Search: 473/376
• US Class Current: 473/376
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: A63B 37/0035 Density; Specific gravity
• 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 37/00621 Centre hardness
• CPC Class Codes: A63B 37/00622 Surface hardness
• CPC Class Codes: A63B 37/0063 Hardness gradient
• CPC Class Codes: A63B 37/0064 Diameter
• CPC Class Codes: A63B 37/0065 Deflection or compression
• CPC Class Codes: A63B 37/0066 Density; Specific gravity
• CPC Class Codes: A63B 37/0076 Multi-piece balls, i.e. having two or more intermediate layers
• CPC Class Codes: A63B 37/0087 Deflection or compression
• CPC Class Codes: A63B 37/0092 Hardness distribution amongst different ball layers

Abstract

Golf balls consisting of a multi-layer core and a cover are disclosed. The multi-layer core consists of a rubber center and a rubber outer core layer that are both soft relative to a hard, thermoplastic intermediate core layer.

Claims

1. A golf ball comprising:

a center formed from a first rubber composition and having a diameter of from 1.00 inches to 1.58 inches and a center hardness of from 35 Shore C to 70 Shore C;

an intermediate core layer formed from a thermoplastic composition and having a surface hardness of 40 Shore C or greater;

an outer core layer formed from a second rubber composition and having a surface hardness of 45 Shore C or greater; and

a cover layer having a surface hardness of 60 Shore D or less;

the intermediate core layer having a surface hardness that is greater than both center hardness of the center and surface hardness of the outer core layer;

wherein the center, the intermediate layer, and the outer core layer each have a specific gravity of from 1.05 g/cc to 1.25 g/cc.

2. The golf ball of claim 1, wherein the diameter of the center is from 1.00 inches to 1.50 inches.

3. The golf ball of claim 1, wherein the core has an overall diameter of from 1.40 inches to 1.64 inches.

4. The golf ball of claim 1, wherein the first rubber composition is a polybutadiene-based rubber composition.

5. The golf ball of claim 1, wherein the first and second rubber compositions are the same or different diene rubber-based compositions.

6. The golf ball of claim 1, wherein the intermediate layer is formed from a thermoplastic composition selected from the group consisting of ionomers, polyesters and polyamides.

7. The golf ball of claim 1, wherein the intermediate layer is formed from a thermoplastic ionomer composition.

8. The golf ball of claim 4, wherein the intermediate layer is formed from a thermoplastic ionomer composition.

9. The golf ball of claim 5, wherein the intermediate layer is formed from a thermoplastic ionomer composition.

10. The golf ball of claim 1, wherein the center, the intermediate layer, and the outer core layer each have a specific gravity of from 1.10 g/cc to 1.18 g/cc.

11. The golf ball of claim 1, wherein the center hardness is from 45 Shore C to 70 Shore C.

12. The golf ball of claim 1, wherein the surface hardness of the intermediate core layer is from 50 Shore C to 95 Shore C.

13. The golf ball of claim 1, wherein the surface hardness of the intermediate core layer is from 85 Shore C to 95 Shore C.

14. The golf ball of claim 1, wherein the surface hardness of the outer core layer is from 55 Shore C to 90 Shore C.