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

• US 7,766,767 B2
• Filed: 05/22/2008
• Issued: 08/03/2010
• Est. Priority Date: 12/15/2005
• 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:
  US12/125,355
• Publication Number:
  US 20080220905A1
• Time in Patent Office: 803 Days
• Field of Search: 473/373, 473/374, 473/376
• US Class Current: 473/373
• CPC Class Codes: A63B 2209/00 Characteristics of used materials
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0051 Materials other than polybutadienes; Constructional details
• CPC Class Codes: A63B 37/006 Physical properties
• CPC Class Codes: A63B 37/0064 Diameter
• CPC Class Codes: A63B 37/0072 with a specified number of layers
• CPC Class Codes: A63B 37/02 Special cores balls with finger holes A63B37/0001, golf ball cores A63B37/005

Abstract

The present invention is directed to golf balls consisting of a dual-layer core and a cover. The core consists of a layer formed from a low modulus HNP composition and a layer formed from a high modulus HNP composition. The low modulus HNP composition has a material hardness of 55 Shore D or less and comprises a highly neutralized ethylene/(meth)acrylic acid/alkyl(meth)acrylate copolymer. The high modulus HNP composition has a material hardness of 45 Shore D or greater and comprises a highly neutralized ethylene/(meth)acrylic acid copolymer. The cover preferably consists of a single cover layer.

Claims

1. A golf ball consisting of:

(a) a center having a diameter of from 0.750 inches to 1.250 inches and formed from 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 outer core layer having a thickness of from 0.150 inches to 0.400 inches 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; and

(c) a cover layer having a thickness of from 0.025 inches to 0.075 inches and a surface hardness of 64 Shore D or less;

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 the center has a diameter of from 0.900 inches to 1.100 inches.

3. The golf ball of claim 1, wherein the outer core layer has a thickness of from 0.250 inches to 0.350 inches.

4. The golf ball of claim 1, wherein the surface hardness of the cover layer is 62 Shore D or less.

5. The golf ball of claim 1, wherein the surface hardness of the cover layer is 58 Shore D or less.

6. A golf ball consisting of:

(a) a center having a diameter of from 0.750 inches to 1.250 inches 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 outer core layer having a thickness of from 0.150 inches to 0.400 inches 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; and

(c) a cover layer having a thickness of from 0.025 inches to 0.075 inches and a surface hardness of 55 Shore D or greater;

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 the center has a diameter of from 0.900 inches to 1.100 inches.

8. The golf ball of claim 6, wherein the outer core layer has a thickness of from 0.250 inches to 0.350 inches.

9. The golf ball of claim 6, wherein the surface hardness of the cover layer is 62 Shore D or greater.

10. The golf ball of claim 6, wherein the surface hardness of the cover layer is 64 Shore D or greater.