Golf balls having a cover layer formed from an ionomer and metallocene-catalyzed polyolefin blend and methods of making same

• US 7,026,395 B2
• Filed: 09/15/2003
• Issued: 04/11/2006
• Est. Priority Date: 01/24/1995
• Status: Expired due to Fees

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Dalton, Jeffrey L., Halko, Roman D., Cavallaro, Christopher, Rajagopalan, Murali, Harris, Kevin M.
• Primary Examiner(s): Buttner, David J.
• Application Number:
  US10/661,532
• Publication Number:
  US 20040063858A1
• Time in Patent Office: 939 Days
• Field of Search: 525/72, 525/74, 473/354, 473/365, 473/373, 473/374
• US Class Current: 525/72
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: A63B 37/0037 Flexural modulus; Bending stiffness
• CPC Class Codes: A63B 37/0045 Thickness
• CPC Class Codes: A63B 37/0052 Liquid cores
• CPC Class Codes: A63B 37/0065 Deflection or compression
• CPC Class Codes: A63B 37/0074 Two piece balls, i.e. cover and core
• CPC Class Codes: A63B 37/0075 Three piece balls, i.e. cover, intermediate layer and core
• CPC Class Codes: A63B 37/00922 whereby hardness of the cover is lower than hardness of the intermediate layers
• CPC Class Codes: A63B 37/04 Rigid 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: C08F 222/06 Maleic anhydride
• CPC Class Codes: C08F 255/00 Macromolecular compounds obtained by polymerising monomers on to polymers of hydrocarbons as defined in group C08F10/00
• CPC Class Codes: C08F 8/00 Chemical modification by after-treatment graft polymers, block polymers, crosslinking with unsaturated monomers or with polymers C08F251/00 - C08F299/00; of conjugated diene rubbers C08C
• CPC Class Codes: C08L 23/08 Copolymers of ethene C08L23/16 takes precedence
• CPC Class Codes: C08L 23/0815 Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 23/0876 Neutralised polymers, i.e. ionomers
• CPC Class Codes: C08L 23/10 Homopolymers or copolymers of propene
• CPC Class Codes: C08L 23/26 modified by chemical after-treatment
• CPC Class Codes: C08L 2314/06 : Metallocene or single site catalysts
• 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 51/06 : grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond
• CPC Class Codes: H04B 1/005 : adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
• CPC Class Codes: H04B 1/006 : using switches for selecting the desired band H04B1/0057 takes precedence

Abstract

The disclosed invention provides a golf ball including a core and a cover of at least two layers, wherein the at least one cover layer includes an inner cover layer of at least one ionomer resin and an outer cover formed from a polymer blend including at least one grafted metallocene-catalyzed polymer and at least one ionomer neutralized with a metal cation, and optionally, a non-grafted metallocene-catalyzed polymer.

Claims

1. A golf ball comprising:

a core comprising polybutadiene and substantially free of organic sulfide;

an inner cover having at least one layer comprising a material having a first Shore D hardness formed over the core and comprising at least two thermoplastic materials, each neutralized with a different metal cation, and wherein the inner cover is substantially free of metallocene-catalyzed polymer; and

an outer cover having at least one layer comprising a polymer blend having a second Shore D hardness less than the first Shore D hardness, disposed about the inner cover, wherein the polymer blend comprises at least one grafted metallocene-catalyzed polymer, a non-ionomeric material comprising an acid-containing ethylene copolymer, and at least two ionomer resins, each neutralized with a different metal cation.

2. The golf ball of claim 1, wherein the polymer blend comprises about 30 percent by weight or greater of the at least one grafted metallocene-catalyzed polymer.

3. The golf ball of claim 1, wherein the at least one grafted metallocene-catalyzed polymer has been functionalized by grafting an ethylenically-unsaturated monomer onto the at least one metallocene-catalyzed polymer using a post-polymerization reaction.

4. The golf ball of claim 1, wherein the core is fluid-filled.

5. The golf ball of claim 1, wherein the golf ball further comprises at least one intermediate layer between the core and the inner cover layer.

6. The golf ball of claim 5, wherein the intermediate layer is a tensioned elastomeric layer.

7. The golf ball of claim 1, wherein the acid-containing ethylene copolymer comprises a copolymer represented by the following structure:

where x=50 to 99 percent, y=1 to 50 percent, z=0 to 49 percent, R₁ is H or CH₃, R₂ is an alkyl group, and n ranges from 0 to 12.

8. The golf ball of claim 7, wherein the acid-containing ethylene copolymer comprises about 10 to about 15 percent methacrylic acid.

9. A golf ball comprising a core, a layer disposed about the core, and a cover, wherein at least one of the core, the layer, or the cover is formed of a blend comprising:

at least one ionomer;

at least one grafted metallocene-catalyzed polymer; and

at least one non-ionomeric material comprising an acid-containing ethylene copolymer.

10. The golf ball of claim 9, wherein the blend is present in the cover.

11. The golf ball of claim 10, wherein the layer comprises at least one ionomer.

12. The golf ball of claim 11, wherein the layer is substantially free of metallocene-catalyzed polymer.

13. The golf ball of claim 9, wherein the at least one ionomer is present in an amount of about 99 to about 25 parts per hundred of the blend, wherein the at least one grafted metallocene-catalyzed polymer blend is present in an amount of about 1 to about 75 parts per hundred of the blend, and wherein the at least one non-ionomeric material is present in an amount of about 1 to about 70 parts per hundred of the blend.

14. The golf ball of claim 13, wherein the at least one ionomer is present in an amount of about 90 to about 70 parts per hundred of the blend, wherein the at least one grafted metallocene-catalyzed polymer blend is present in an amount of about 10 to about 30 parts per hundred of the blend, and wherein the at least one non-ionomeric material is present in an amount of about 1 to about 20 parts per hundred of the blend.

15. The golf ball of claim 9, wherein the layer has a hardness from about 65 Shore D to 80 Shore D and the cover has a second hardness is about 45 Shore D to 60 Shore D.

16. The golf ball of claim 9, wherein the acid-containing ethylene copolymer comprises a copolymer represented by the following structure:

where x=50 to 99 percent, y=1 to 50 percent, z=0 to 49 percent, R₁ is H or CH₃, R₂ is an alkyl group, and n ranges from 0 to 12.

17. The golf ball of claim 16, wherein the acid-containing ethylene copolymer comprises about 10 to about 15 percent methacrylic acid.