Golf balls having a low modulus HNP layer and a high modulus HNP layer

• US 8,057,324 B2
• Filed: 11/15/2010
• Issued: 11/15/2011
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Jones, Douglas E., Sullivan, Michael J., Hebert, Edmund A., Ladd, Derek A.
• Primary Examiner(s): Gorden; Raeann
• Application Number:
  US12/946,024
• Publication Number:
  US 20110059811A1
• Time in Patent Office: 365 Days
• Field of Search: 473/376, 473/373, 473/374
• US Class Current: 473/376
• CPC Class Codes: A63B 2209/00 Characteristics of used materials
• CPC Class Codes: A63B 37/0003 Golf balls
• 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 37/0049 Flexural modulus; Bending stiffness
• CPC Class Codes: A63B 37/00621 Centre hardness
• CPC Class Codes: A63B 37/00622 Surface hardness
• CPC Class Codes: A63B 37/0064 Diameter
• 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: A63B 37/02 Special cores balls with finger holes A63B37/0001, golf ball cores A63B37/005
• CPC Class Codes: C08L 23/0876 Neutralised polymers, i.e. ionomers

Abstract

The present invention is directed to golf balls consisting of a multi-layer core and a cover. The multi-layer core consists of a center and an outer core layer that are both soft relative to a hard intermediate core layer. The outer core layer is preferably thin relative to the center and the outer core layer. The multi-layer core includes at least one layer formed from a low modulus HNP composition and at least one layer formed from a high modulus HNP composition.

Claims

1. A golf ball comprising a core and a cover, wherein the core has an overall diameter of from 1.40 inches to 1.60 inches and consists of:

(a) a center having a diameter of from 0.50 inches to 1.50 inches, a center hardness (H) of from 20 Shore C to 70 Shore C, and formed from a low modulus HNP composition, the low modulus HNP composition comprising a highly neutralized ethylene/(meth)acrylic acid/alkyl(meth)acrylate copolymer having a modulus of from 1,000 psi to 50,000 psi;

(b) an intermediate core layer having a surface hardness (I) of 40 Shore C or greater and formed from a rubber composition; and

(c) an outer core layer having a surface hardness (S) of from 20 Shore C to 70 Shore C and formed from a high modulus HNP composition, the high modulus HNP composition comprising a highly neutralized ethylene/(meth)acrylic acid copolymer having a modulus of from 25,000 psi to 150,000 psi;

wherein H<

I and S<

I, and

wherein the modulus of the highly neutralized copolymer of the low modulus HNP composition is at least 10% less than the modulus of the highly neutralized copolymer of the high modulus HNP composition.

2. The golf ball of claim 1, wherein H<

S, and wherein S−

H=D, where D is an integer from 1 to 22.

3. The golf ball of claim 1, wherein S<

H, and wherein H−

S=D, where D is an integer from 1 to 22.

4. The golf ball of claim 1, wherein the center has a diameter of from 0.750 inches to 1.500 inches and the center hardness (H) is from 50 Shore C to 60 Shore C;

the intermediate core layer surface hardness (I) is from 80 Shore C to 90 Shore C; and

the outer core layer has a thickness of from 0.010 inches to 0.150 inches and the outer core layer surface hardness (S) is from 50 Shore C to 60 Shore C.

5. The golf ball of claim 4, wherein the outer core layer has a thickness of from 0.030 inches to 0.070 inches.

6. A golf ball comprising a core and a cover, wherein the core has an overall diameter of from 1.40 inches to 1.60 inches and consists of:

(a) a center having a diameter of from 0.50 inches to 1.50 inches, a center hardness (H) of from 20 Shore C to 70 Shore C, and formed from a high modulus HNP composition, the high modulus HNP composition comprising a highly neutralized ethylene/(meth)acrylic acid copolymer having a modulus of from 25,000 psi to 150,000 psi;

(b) an intermediate core layer having a surface hardness (I) of 40 Shore C or greater and formed from a rubber composition; and

(c) an outer core layer having a surface hardness (S) of from 20 Shore C to 70 Shore C and formed from a low modulus HNP composition, the low modulus HNP composition comprising a highly neutralized ethylene/(meth)acrylic acid/alkyl (meth)acrylate copolymer having a modulus of from 1,000 psi to 50,000 psi;

wherein H<

I and S<

I, and

wherein the modulus of the highly neutralized copolymer of the low modulus HNP composition is at least 10% less than the modulus of the highly neutralized copolymer of the high modulus HNP composition.

7. The golf ball of claim 6, wherein H<

S, and wherein S−

H=D, where D is an integer from 1 to 22.

8. The golf ball of claim 6, wherein S<

H, and wherein H−

S=D, where D is an integer from 1 to 22.

9. The golf ball of claim 6, wherein the center has a diameter of from 0.750 inches to 1.500 inches and the center hardness (H) is from 50 Shore C to 60 Shore C;

the intermediate core layer surface hardness (I) is from 80 Shore C to 90 Shore C; and

the outer core layer has a thickness of from 0.010 inches to 0.150 inches and the outer core layer surface hardness (S) is from 50 Shore C to 60 Shore C.

10. The golf ball of claim 9, wherein the outer core layer has a thickness of from 0.030 inches to 0.070 inches.