Golf balls having two or more core layers formed from HNP compositions

• US 8,057,325 B2
• Filed: 01/17/2011
• Issued: 11/15/2011
• Est. Priority Date: 04/23/2007
• Status: Active Grant

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Morgan, William E., Dalton, Jeffrey L., Sullivan, Michael J., Ladd, Derek A.
• Primary Examiner(s): Gorden; Raeann
• Application Number:
  US13/008,012
• Publication Number:
  US 20110111886A1
• Time in Patent Office: 302 Days
• Field of Search: 473/376
• 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 37/0033 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 37/0051 Materials other than polybutadienes; Constructional details
• 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 37/02 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 an inner core layer formed from a relatively hard HNP composition and an outer core layer formed from a relatively soft HNP composition. The outer core layer has an outer surface hardness less than the outer surface hardness of the inner core layer.

Claims

1. A golf ball comprising a core and a cover, wherein the core has an overall diameter of from 1.400 inches to 1.660 inches and comprises:

an inner core layer having a diameter of from 0.125 inches to 1.000 inches, an outer surface hardness of from 80 Shore C to 95 Shore C, and formed from a first HNP composition, the first HNP composition having a material hardness of 45 Shore D or greater and comprising a highly neutralized ethylene/(meth)acrylic acid copolymer;

an intermediate core layer formed from a rubber composition and having a thickness of from 0.050 inches to 0.400 inches; and

an outer core layer having an outer surface hardness less than the outer surface hardness of the inner core layer, and formed from a second HNP composition, the second HNP composition having a material hardness of 55 Shore D or less and comprising a highly neutralized ethylene/(meth)acrylic acid/alkyl (meth)acrylate copolymer.

2. The golf ball of claim 1, wherein the outer core layer has a specific gravity greater than or equal to the inner core layer specific gravity.

3. The golf ball of claim 1, wherein the core has an overall diameter of from 1.510 inches to 1.600 inches.

4. The golf ball of claim 1, wherein the inner core layer has a diameter of from 0.250 inches to 0.375 inches.

5. The golf ball of claim 1, wherein the cover consists of a single layer having an outer surface hardness of 60 Shore D or less and a thickness of from 0.015 inches to 0.100 inches.

6. The golf ball of claim 1, wherein the cover consists of:

an inner cover layer having an outer surface hardness of 65 Shore D or greater and a thickness of from 0.020 inches to 0.080 inches; and

an outer cover layer having an outer surface hardness of 60 Shore D or less and a thickness of from 0.015 inches to 0.055 inches.

7. The golf ball of claim 1, wherein the cover consists of:

an inner cover layer formed from a partially or fully neutralized polymer composition and having an outer surface hardness of 65 Shore D or greater and a thickness of from 0.015 inches to 0.035 inches; and

an outer cover layer formed from a polyurethane or polyurea composition and having a material hardness of 50 Shore D or less and a thickness of from 0.015 inches to 0.035 inches.