GOLF BALL

• US 20110244989A1
• Filed: 04/05/2011
• Published: 10/06/2011
• Est. Priority Date: 04/06/2010
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Dunlop Sports Co. Ltd. (Sumitomo Rubber Industries Limited)
• Inventors: OKAMOTO, Hirokazu, HORIUCHI, Kuniyasu, SHIRAISHI, Masahiko, TARAO, Toshiyuki, ISOGAWA, Kazuhiko
• Granted Patent: US 9,259,617 B2
• Time in Patent Office: Days
• US Class Current: 473/385
• CPC Class Codes: A63B 37/00221 characterised by the material
• CPC Class Codes: A63B 37/00222 Physical properties, e.g. hardness
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: C08G 18/00 Polymeric products of isocyanates or isothiocyanates
• CPC Class Codes: C08G 18/02 of isocyanates or isothiocyanates only
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/12 using two or more compounds having active hydrogen in the first polymerisation step

Abstract

An object of the present is to provide a golf ball having a high spin rate on approach shots under the wet condition and rough condition. The present invention provides a golf ball comprising a golf ball body, and a paint film formed on a surface of the golf ball body, wherein the paint film has a martens hardness of 2.0 mgf/μm² or less, and a ratio (50% modulus/10% modulus) of 50% modulus to 10% modulus of 1.6 or more.

Claims

1. A golf ball comprising

a golf ball body, and

a paint film formed on a surface of the golf ball body,

wherein the paint film has a martens hardness of 2.0 mgf/μ

m² or less, and a ratio (50% modulus/10% modulus) of 50% modulus to 10% modulus of 1.6 or more.

2. The golf ball according to claim 1, wherein a base resin constituting the paint film is polyurethane obtained by a reaction between a polyol component and a polyisocyanate component, and the polyisocyanate component includes a biuret-modified product of hexamethylene diisocyanate.

3. The golf ball according to claim 1, wherein the paint film has a 10% modulus of 100 kgf/cm² or less.

4. The golf bail according to claim 1, wherein the paint film has a 10% modulus of 50 kgf/cm² or less.

5. The golf ball according to claim 1, wherein the paint film has a 50% modulus of 30 kgf/cm² or more.

6. The golf ball according to claim 1, wherein the paint film contains at least one filler selected from the group consisting of titanium oxide, barium sulfate, talc, calcium carbonate, clay, and white carbon.

7. The golf ball according to claim 6, wherein the paint film contains the filler in a content ranging from 10 mass % to 50 mass %.

8. The golf ball according to claim 1, wherein the golf ball has a cover with a Shore D hardness of 61 or less.

9. The golf ball according to claim 8, wherein the cover has a thickness ranging from 0.3 mm to 1.0 mm.

10. The golf ball according to claim 1, the paint film has a thickness ranging from 5 μ

m to 40 μ

m.

11. The golf ball according to claim 4, wherein the paint film has a 10% modulus of 5 kgf/cm² or more.

12. The golf ball according to claim 5, wherein the paint film has a 50% modulus of 200 kgf/cm² or less.

13. The golf ball according to claim 1, wherein the paint film has a ratio (50% modulus/10% modulus) of 50% modulus to 10% modulus of 15 or less.

14. The golf ball according to claim 2, wherein the polyol component has a hydroxyl value ranging from 10 mgKOH/g to 400 mgKOH/g.

15. The golf ball according to claim 2, wherein the polyisocyanate component contains a mixture of the biuret-modified product of hexamethylene diisocyanate and an isocyanurate of isophorone diisocyanate.

16. The golf ball according to claim 15, wherein a blending ratio of the biuret-modified product of hexamethylene diisocyanate and the isocyanurate of isophorone diisocyanate is such that the biuret-modified product of hexamethylene diisocyanate:

the isocyanurate of isophorone diisocyanate being 1;

0 to 0.7;

0.3

17. The golf ball according to claim 2, wherein the polyisocyanate component has an isocyanate content (NCO %) ranging from 0.5 mass % to 45 mass %.

18. The golf ball according to claim 2, wherein a molar ratio (NCO/OH) of the isocyanate group (NCO) of the polyisocyanate component to the hydroxyl group (OH) of the polyol component ranges from 1.0 to 1.4 in the reaction.

19. A golf ball comprising

a colored golf ball body, and

a paint film formed on a surface of the golf ball body,

wherein the paint film has a martens hardness of 2.0 mgf/μ

m² or less, a 10% modulus ranging from 5 kgf/cm² to 100 kgf/cm², a 50% modulus ranging from 30 kgf/cm² to 200 kgf/cm² and a ratio (50% modulus/10% modulus) of 50% modulus to 10% modulus of 1.6 or more, and wherein the paint film is a substantially transparent paint film containing a filler.

20. The golf ball according to claim 19, wherein the paint film has a thickness ranging from 5 μ

m to 40 μ

m.