Golf ball

Patent metadata

Field	Value
Publication number	US-9757621-B2
Application number	US-201615067414-A
Country	US
Kind code	B2
Filing date	Mar 11, 2016
Priority date	Mar 31, 2015
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

An object of the present invention is to provide a golf ball having excellent shot feeling and flight distance. The present invention provides a golf ball comprising a spherical core, a first resin layer and a second resin layer, wherein the first resin layer is formed from a first resin composition containing (A) a polyamide resin, (B) a copolymer and/or a metal ion-neutralized product thereof, and (C) a thermoplastic elastomer, and having a ratio (flexural elastic modulus/slab hardness) of a flexural elastic modulus (MPa) to a slab hardness (Shore D hardness) in a range from 3 to 5; and the second resin layer is formed from a second resin composition containing (D) a polyamide resin, and (E) a copolymer and/or a metal ion-neutralized product thereof.

First claim

The invention claimed is:

1. A golf ball comprising a spherical core and at least two envelope layers covering the spherical core,
wherein the envelope layers comprise at least one first resin layer and at least one second resin layer;
the first resin layer is formed from a first resin composition having a ratio (flexural elastic modulus/slab hardness) of a flexural elastic modulus (MPa) thereof to a slab hardness (Shore D hardness) thereof in a range from 3 to 5, and containing, as a resin component, (A) a polyamide resin, (B) at least one selected from the group consisting of (b-1) a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-2) a metal ion-neutralized product of a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-3) a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester, and (b-4) a metal ion-neutralized product of a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester, and (C) a thermoplastic elastomer different from the (A) component and the (B) component; and
the second resin layer is formed from a second resin composition containing, as a resin component, (D) a polyamide resin, and (E) at least one selected from the group consisting of (e-1) a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (e-2) a metal ion-neutralized product of a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (e-3) a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester, and (e-4) a metal ion-neutralized product of a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester, and
wherein a mass ratio ((D):(E)) of the (D) component and the (E) component ranges from 15 to 80:85 to 20 in the second resin composition, based a total of the (D) component and the (E) component of 100.

2. The golf ball according to claim 1 , wherein a ratio (slab hardness×flexural elastic modulus/content of (A) component) of a product obtained by multiplying the slab hardness (Shore D hardness) by the flexural elastic modulus (MPa) to a content (mass %) of the (A) component in the resin component is 1050 or less in the first resin composition.

3. The golf ball according to claim 1 , wherein the slab hardness of the first resin composition ranges from 45 to 65 in Shore D hardness.

4. The golf ball according to claim 1 , wherein the flexural elastic modulus of the first resin composition ranges from 130 MPa to 400 MPa.

5. The golf ball according to claim 1 , wherein a mass ratio ((A):(B):(C)) of the (A) component, the (B) component and the (C) component ranges from 10 to 60:5 to 80:5 to 50 in the first resin composition, based on a total of the (A) component, the (B) component and the (C) component of 100.

6. The golf ball according to claim 1 , wherein the (C) component of the first resin composition contains a styrene-based thermoplastic elastomer.

7. The golf ball according to claim 1 , wherein the second resin composition further contains (F) an organically modified layered silicate.

8. The golf ball according to claim 1 , wherein the second resin composition has a slab hardness in a range from 65 to 80 in Shore D hardness.

9. The golf ball according to claim 1 , wherein the second resin composition has a flexural elastic modulus in a range from 400 MPa to 4000 MPa.

10. The golf ball according to claim 1 , wherein the envelop layers comprise an inner intermediate layer disposed outside the spherical core and an outer intermediate layer disposed outside the inner intermediate layer and a cover disposed outside the outer intermediate layer; and
the inner intermediate layer is formed from the first resin composition, and the outer intermediate layer is formed from the second resin composition.

11. The golf ball according to claim 1 , wherein the envelop layers comprise an inner intermediate layer disposed outside the spherical core and an outer intermediate layer disposed outside the inner intermediate layer and a cover disposed outside the intermediate layer; and
the inner intermediate layer is formed from the second resin composition, and the outer intermediate layer is formed from the first resin composition.

12. The golf ball according to claim 1 , wherein a hardness difference (second resin composition−first resin composition) between the slab hardness of the first resin composition and the slab hardness of the second resin composition ranges from 12 to 25 in Shore D hardness.

13. The golf ball according to claim 1 , wherein a flexural elastic modulus difference (second resin composition−first resin composition) between the flexural elastic modulus of the first resin composition and the flexural elastic modulus of the second resin composition ranges from 300 MPa to 900 MPa.

14. The golf ball according to claim 1 , wherein the second resin composition has a ratio (flexural elastic modulus/slab hardness) of a flexural elastic modulus (MPa) to a slab hardness (Shore D hardness) in a range from 3 to 15.

15. The golf ball according to claim 1 , wherein the first resin layer has a thickness in a range from 0.5 mm to 3.0 mm.

16. The golf ball according to claim 1 , wherein the second resin layer has a thickness in a range from 0.5 mm to 4.0 mm.

17. The golf ball according to claim 7 , wherein a content of the (F) organically modified layered silicate ranges from 0.1 part by mass to 50 parts by mass with respect to 100 parts by mass of a total amount of the (D) component and the (E) component.

18. The golf ball according to claim 10 , wherein the cover has a slab hardness in a range from 25 to 50 in Shore D hardness, and a flexural elastic modulus in a range from 2 MPa to 80 MPa.

19. The golf ball according to claim 11 , wherein the cover has a slab hardness in a range from 25 to 50 in Shore D hardness, and a flexural elastic modulus in a range from 2 MPa to 80 MPa.

20. The golf ball according to claim 1 , wherein a mass ratio ((A):(B):(C)) of the (A) component, the (B) component and the (C) component ranges from 10 to 60:5 to 80:5 to 50 in the first resin composition based on a total of the (A) component, the (B) component and the (C) component of 100,
the first resin composition has a slab hardness in a range from 45 to 65 in Shore D hardness, and a flexural elastic modulus in a range from 130 MPa to 400 MPa,
the second resin composition has a slab hardness in a range from 65 to 80 in Shore D hardness, and a flexural elastic modulus in a range from 400 MPa to 4000 MPa,
a hardness difference (second resin composition−first resin composition) between the slab hardness of the first resin composition and the slab hardness of the second resin composition ranges from 12 to 25 in Shore D hardness, and
a flexural elastic modulus difference (second resin composition−first resin composition) between the flexural elastic modulus of the first resin composition and the flexural elastic modulus of the second resin composition ranges from 300 MPa to 900 MPa.

Assignees

• Dunlop Sports Co Ltd
• Dunlop Sports Co Ltd

Inventors

• Inoue Hidetaka
• Tarao Toshiyuki
• Tanaka Mami

Classifications

• A63B37/0049

  Flexural modulus; Bending stiffness · CPC title

• C08K5/098

  Metal salts of carboxylic acids · CPC title

• A63B37/0075

  Three piece balls, i.e. cover, intermediate layer and core · CPC title

• C08L77/00

  Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain (of polyhydrazides C08L79/06; of polyamideimides or polyamide acids C08L79/08); Compositions of derivatives of such polymers · CPC title

• A63B37/0047

  Density; Specific gravity · CPC title