Multi-layer core golf ball

• US 9,592,425 B2
• Filed: 10/30/2014
• Issued: 03/14/2017
• Est. Priority Date: 04/20/2012
• Status: Active Grant

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Goguen, Douglas S., Sullivan, Michael J., Comeau, Brian
• Primary Examiner(s): Gorden, Raeann
• Application Number:
  US14/527,835
• Publication Number:
  US 20150057105A1
• Time in Patent Office: 866 Days
• Field of Search: 473/376
• US Class Current: 1/1
• 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 37/0058 Polyurethane
• CPC Class Codes: A63B 37/0059 Ionomer
• CPC Class Codes: A63B 37/00621 Centre hardness
• CPC Class Codes: A63B 37/00622 Surface hardness
• CPC Class Codes: A63B 37/0063 Hardness gradient
• CPC Class Codes: A63B 37/0064 Diameter
• CPC Class Codes: A63B 37/0075 Three piece balls, i.e. cover, intermediate layer and core
• 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 13/00 Compositions of rubbers containing carboxyl groups
• CPC Class Codes: C08L 21/00 Compositions of unspecified rubbers
• CPC Class Codes: C08L 23/0876 Neutralised polymers, i.e. ionomers
• CPC Class Codes: C08L 75/04 Polyurethanes

Abstract

A golf ball comprising a core and a cover, the core consisting of: a solid inner core layer formed from a first unfoamed thermoplastic composition TP₁ and having a diameter of 1.10 inch or less and a center Shore C hardness (H_center) of 50 or less, one or more optional intermediate core layers, and an outer core layer formed from a second thermoplastic composition TP₂ comprising at least one transparent or plasticized polyamide and having a thickness of 0.200 inches or greater and an outer surface Shore D hardness (H_{outer surface}) of 55 or greater, wherein H_{outer surface}+30 >H_center, and H_{outer surface}+30 −H_center≧40.

Claims

1. A golf ball comprising a core and a cover, wherein the core consists of:

a solid inner core layer formed from a first unfoamed thermoplastic composition TP₁ and having a diameter of 1.10 inch or less and a center Shore C hardness (H_center) of 15 or less,

an intermediate core layer, and

an outer core layer formed from a second thermoplastic composition TP₂ comprising at least one transparent or plasticized polyamide and having a thickness of 0.40 inches or greater and an outer surface Shore D hardness (H_{outer surface}) of 55 or greater,

wherein H_{outer surface}+30>

H_center, and H_{outer surface}+30−

H_center>

70.

2. The golf ball of claim 1, wherein H_{outer surface}+30−

H_center≧

85.

3. The golf ball of claim 1, wherein the inner core layer has an inner core interface Shore C hardness H_{inner core interface} such that −

5≦

H_{inner core interface}−

H_center≧

5.

4. The golf ball of claim 1, wherein TP₁ comprises at least one of ionomers;

non- ionomeric acid polymers;

polyurethanes, polyureas, and polyurethane-polyurea hybrids;

polyester-based thermoplastic elastomers;

polyamides, copolymers of ionomer and polyamide, polyamide-ethers, and polyamide-esters;

ethylene-based homopolymers and copolymers;

propylene-based homopolymers and copolymers;

triblock copolymers based on styrene and ethylene/butylene;

derivatives thereof that are compatibilized with at least one grafted or copolymerized functional group; and

combinations thereof.

5. The golf ball of claim 1, wherein TP₂ comprises at least one of ionomers;

non- ionomeric acid polymers;

polyurethanes, polyureas, and polyurethane-polyurea hybrids;

polyester-based thermoplastic elastomers;

polyamides, copolymers of ionomer and polyamide, polyamide-ethers, and polyamide-esters;

ethylene-based homopolymers and copolymers;

propylene-based homopolymers and copolymers;

triblock copolymers based on styrene and ethylene/butylene;

derivatives thereof that are compatibilized with at least one grafted or copolymerized functional group; and

combinations thereof.

6. The golf ball of claim 1, wherein the intermediate core layer is formed from a thermoset composition comprising at least one of natural rubber, polybutadiene, polyisoprene, ethylene propylene rubber (EPR), ethylene-propylene-diene rubber (EPDM), styrene-butadiene rubber, butyl rubber, halobutyl rubber, polyurethane, polyurea, acrylonitrile butadiene rubber, polychloroprene, alkyl acrylate rubber, chlorinated isoprene rubber, acrylonitrile chlorinated isoprene rubber, polyalkenamer, phenol formaldehyde, melamine formaldehyde, polyepoxide, polysiloxane, polyester, alkyd, polyisocyanurate, polycyanurate, polyacrylate, and combinations thereof.

7. The golf ball of claim 1, wherein the inner core layer has a diameter that is less than 1.0 inch.

8. The golf ball of claim 7, wherein the outer core layer has a thickness of greater than 0.45 inches.