Multi-layer golf ball

• US 8,012,044 B2
• Filed: 03/01/2010
• Issued: 09/06/2011
• Est. Priority Date: 06/01/1993
• Status: Expired due to Fees

• Current Assignee: Callaway Golf Company
• Original Assignee: Callaway Golf Company
• Inventors: Tzivanis, Michael T., Keller, Viktor, Risen, William M. Jr., Nealon, John L., Kennedy, Thomas J. III, Binette, Mark L.
• Primary Examiner(s): Gorden; Raeann
• Application Number:
  US12/715,264
• Publication Number:
  US 20100160077A1
• Time in Patent Office: 554 Days
• Field of Search: 473/373, 473/374
• 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 37/003 Coefficient of restitution
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0034 Deflection or compression
• CPC Class Codes: A63B 37/0043 Hardness
• CPC Class Codes: A63B 37/0096 Spin rate
• CPC Class Codes: A63B 37/02 Special cores balls with finger holes A63B37/0001, golf ball cores A63B37/005
• CPC Class Codes: A63B 37/06 Elastic cores
• CPC Class Codes: A63B 37/12 Special coverings , i.e. outer layer material balls with finger holes A63B37/0001, golf ball covers A63B37/0023
• CPC Class Codes: C08G 18/42 Polycondensates having carboxylic or carbonic ester groups in the main chain
• CPC Class Codes: C08G 2120/00 Compositions for reaction injection moulding processes
• CPC Class Codes: C08L 101/00 Compositions of unspecified macromolecular compounds
• 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 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• 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 2666/14 Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C08L 2666/18 Polyesters or polycarbonates according to C08L67/00 - C08L69/00; Derivatives thereof
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 69/00 : Compositions of polycarbonates; Compositions of derivatives of polycarbonates
• CPC Class Codes: C08L 75/04 : Polyurethanes

Abstract

Disclosed herein is a multi-layer golf ball having a soft outer cover. The golf ball has an inner cover layer with a Shore D hardness of 60 or more, and an outer cover with a Shore D hardness of 55 or less, and more preferably 50 or less. In a particularly preferred form of the invention, the outer cover comprises one or more polyurethane materials. The golf ball of the invention has exceptionally soft feel and high spin rates on short shots of 80 yards or less, and particularly, 40 yards or less, while maintaining good distance and average spin on full shots.

Claims

1. A golf ball comprising:

a core;

an inner cover layer disposed on the core and having a thickness ranging from 0.030 inch to 0.070 inch, the inner cover layer comprising a blend of ionomers, the blend of ionomers comprising a first ionomer with an acid content by weight of 16% or less and 10% to 100% neutralization of the first ionomer by sodium metal ions, and a second ionomer with an acid content by weight of 18% or more and 10% to 100% neutralization of the second ionomer by zinc metal ions;

and an outer cover layer disposed on the inner cover layer, the outer cover layer having a Shore D hardness of no more than 55 as measured on the curved surface thereof and comprising a thermoplastic polyurethane and having a thickness ranging from 0.030 inch to 0.060 inch;

wherein the golf ball exhibits a PGA compression of 100 or less and a coefficient of restitution of at least 0.770.

2. The golf ball of claim 1, wherein the inner cover layer further comprises a metal fatty acid salt.

3. The golf ball of claim 2, wherein the metal fatty acid salt is a metal stearate.

4. The golf ball of claim 3, wherein the metal stearate comprises a metal selected from the group consisting of zinc, sodium and magnesium.

5. The golf ball of claim 1, wherein the core is solid and is composed of a polybutadiene mixture.

6. The golf ball of claim 1, wherein the core is solid and is formed from materials comprising at least one polybutadiene and an ethylenically unsaturated carboxylic acid selected from the group consisting of zinc diacrylate, zinc acrylate and zinc methacrylate.

7. The golf ball of claim 1, wherein the core is solid and is formed from materials comprising at least one polybutadiene, zinc oxide and an ethylenically unsaturated carboxylic acid selected from the group consisting of zinc diacrylate, zinc acrylate and zinc methacrylate.

8. The golf ball of claim 7, wherein the ethylenically unsaturated carboxylic acid is zinc diacrylate.

9. The golf ball of claim 1, wherein the core is a thread wound core having a liquid filled center.