Three-layer-core golf ball having highly-neutralized polymer outer core layer

• US 9,616,296 B2
• Filed: 08/12/2014
• Issued: 04/11/2017
• Est. Priority Date: 06/26/2001
• Status: Expired due to Fees

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Rajagopalan, Murali, Sullivan, Michael J.
• Primary Examiner(s): SELLERS, ROBERT E
• Application Number:
  US14/457,159
• Publication Number:
  US 20140349781A1
• Time in Patent Office: 973 Days
• Field of Search: None
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: A63B 37/0039 characterised by the material
• 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 37/0049 Flexural modulus; Bending stiffness
• CPC Class Codes: A63B 37/00622 Surface hardness
• 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 37/0092 Hardness distribution amongst different ball layers
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 23/08 Copolymers of ethene C08L23/16 takes precedence
• CPC Class Codes: C08L 23/0876 Neutralised polymers, i.e. ionomers
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: Y10T 428/24983 Hardness

Abstract

A golf ball includes an inner core layer formed from a thermoset rubber composition. The inner core layer has a first outer surface Shore D hardness and an outer diameter of about 0.8 to 1.40 inches. A thermoplastic outer core layer is formed around the inner core layer, has a second outer surface Shore D hardness, and is formed from a copolymer of ethylene and an α,β-unsaturated carboxylic acid, a magnesium salt of oleic acid, and sufficient cation source to fully-neutralize the acid groups of the copolymer. The golf ball includes an inner cover layer and an outer cover layer. The first outer surface Shore D hardness is greater than the second outer surface Shore D hardness and the outer core layer has a thickness of about 0.01 inches to 0.05 inches.

Claims

1. A golf ball comprising:

an inner core layer comprising a thermoset rubber composition and having a first outer surface Shore D hardness and an outer diameter of about 1.0 inch to about 1.6 inches;

a thermoplastic outer core layer having a second outer surface Shore D hardness, and comprising a copolymer of ethylene and an α

,β

-unsaturated carboxylic acid, a magnesium salt of oleic acid, and sufficient cation source to fully-neutralize the acid groups of the copolymer;

an inner cover layer; and

an outer cover layer;

wherein the first outer surface Shore D hardness is less than the second outer surface Shore D hardness and the outer core layer has a thickness of about 0.02 inches to about 0.150 inches.

2. The golf ball of claim 1, wherein the inner core outer diameter is about 1.2 to 1.58 inches.

3. The golf ball of claim 2, wherein the inner core outer diameter is about 1.3 to 1.56 inches.

4. The golf ball of claim 1, wherein the first outer surface hardness is about 30 Shore D to about 65 Shore D and the second outer surface hardness is about 35 Shore D to about 70 Shore D.

5. The golf ball of claim 4, wherein the first outer surface hardness is about 35 Shore D to about 60 Shore D and the second outer surface hardness is about 40 Shore D to about 65 Shore D.

6. The golf ball of claim 5, wherein the first outer surface hardness is about 40 Shore D to about 55 Shore D and the second outer surface hardness is about 45 Shore D to about 60 Shore D.

7. The golf ball of claim 1, wherein the outer core layer thickness is about 0.04 inches to about 0.125 inches.

8. The golf ball of claim 7, wherein the outer core layer thickness is about 0.05 inches to about 0.095 inches.

9. A golf ball comprising:

an inner core layer comprising a thermoset rubber composition and having a first outer surface Shore D hardness and an outer diameter of about 0.8 inches to about 1.6 inches;

a thermoplastic outer core layer having a second outer surface Shore D hardness, and comprising a copolymer of ethylene and an α

,β

-unsaturated carboxylic acid, a magnesium salt of oleic acid, and sufficient cation source to fully-neutralize the acid groups of the copolymer;

an inner cover layer; and

an outer cover layer;

wherein the first outer surface Shore D hardness is greater than the second outer surface Shore D hardness and the outer core layer has a thickness of about 0.02 inches to about 0.150 inches.

10. The golf ball of claim 9, wherein the inner core outer diameter is about 1.0 inches to about 1.58 inches.

11. The golf ball of claim 10, wherein the inner core outer diameter is about 1.2 inches to about 1.56 inches.

12. The golf ball of claim 9, wherein the outer core layer thickness is about 0.04 inches to about 0.125 inches.

13. The golf ball of claim 12, wherein the outer core layer thickness is about 0.05 inches to about 0.095 inches.