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

• US 9,457,233 B2
• Filed: 11/05/2014
• Issued: 10/04/2016
• Est. Priority Date: 06/26/2001
• Status: Expired due to Term

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Sullivan, Michael J., Comeau, Brian
• Primary Examiner(s): SELLERS, ROBERT E
• Application Number:
  US14/533,189
• Publication Number:
  US 20150072806A1
• Time in Patent Office: 699 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: A63B 37/0024 Materials other than ionomers or polyurethane
• 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 37/0072 with a specified number of layers
• 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: B32B 7/022 Mechanical properties
• CPC Class Codes: C08K 5/101 of monocarboxylic acids
• CPC Class Codes: C08L 101/00 Compositions of unspecified macromolecular compounds
• 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: C08L 75/04 : Polyurethanes
• 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 1.0 to 1.6 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 an acid copolymer of ethylene and an α,β-unsaturated carboxylic acid, optionally including a softening monomer, such as alkyl acrylates and methacrylates; a plasticizer; and a cation source present in an amount sufficient to neutralize about 70 to 100% of the acid groups present in the material. The golf ball an inner and outer cover layers. The second outer surface Shore D hardness is greater than the first outer surface Shore D hardness.

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;

an outer core layer having a thickness of about 0.02 inches to about 0.15 inches and a second outer surface Shore D hardness greater than the first;

an inner cover layer; and

an outer cover layer;

wherein the outer core layer comprises a thermoplastic material comprising;

an acid copolymer of ethylene and an α

,β

-unsaturated carboxylic acid, optionally including a softening monomer selected from the group consisting of alkyl acrylates and methacrylates;

a plasticizer; and

a cation source present in an amount sufficient to neutralize from about 80% to about 100% of all acid groups present in the material.

2. 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.

3. The golf ball of claim 2, 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.

4. The golf ball of claim 1, wherein the plasticizer is present in an amount of about 3 to 50% by weight.

5. The golf ball of claim 1, wherein the plasticizer comprises a fatty acid ester.

6. The golf ball of claim 5, wherein the plasticizer comprises an alkyl oleate.

7. The golf ball of claim 6, wherein the alkyl oleate comprises methyl oleate, ethyl oleate, propyl oleate, butyl oleate, octyl oleate, 2-ethylhexyl oleate, or mixtures thereof.

8. The golf ball of claim 7, wherein the plasticizer comprises butyl oleate or glycerol trioleate.

9. The golf ball of claim 1, wherein 90% or greater of the acid groups are neutralized.

10. The golf ball of claim 9, wherein 100% of the acid groups are neutralized.

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

12. The golf ball of claim 11, wherein the inner core outer diameter is about 1.3 to 1.56 inches.

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

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

15. 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 an acid copolymer of ethylene and an α

,β

-unsaturated carboxylic acid, optionally including a softening monomer selected from the group consisting of alkyl acrylates and methacrylates, a plasticizer comprising butyl oleate or glycerol trioleate; and

a cation source present in an amount sufficient to neutralize from about 80 to about 100% of all acid groups present in the material;

an inner cover layer; and

an outer cover layer;

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, and wherein the outer core layer has a thickness of about 0.02 inches to about 0.150 inches.

17. The golf ball of claim 15, wherein the plasticizer is present in an amount of about 3 to 50% by weight.

18. The golf ball of claim 15, wherein 90% or greater of the acid groups are neutralized.

16. 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 an acid copolymer of ethylene and an α

,β

-unsaturated carboxylic acid;

a plasticizer comprising butyl oleate or glycerol trioleate; and

a cation source present in an amount sufficient to neutralize from about 90 to about 100% of all acid groups present in the material;

an inner cover layer; and

an outer cover layer;

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, and wherein the outer core layer has a thickness of about 0.02 inches to about 0.150 inches.

19. The golf ball of claim 16, wherein the plasticizer is present in an amount of about 3 to 50% by weight.

20. The golf ball of claim 16, wherein 90% or greater of the acid groups are neutralized.