Golf ball resin composition and golf ball

1. A golf ball 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, wherein the slab hardness of the golf ball resin composition is 61 or less in Shore D hardness.

2. The golf ball resin composition according to claim 1 , wherein a ratio (slab hardness×flexural elastic modulus/content of (A) component) is 1050 or less,

the ratio (slab hardness×flexural elastic modulus/content of (A) component) is obtained by dividing a product (slab hardness×flexural elastic modulus) by a content (mass %) of the (A) component in the resin component of the golf ball resin composition, and

the product (slab hardness×flexural elastic modulus) is obtained by multiplying the slab hardness (Shore D hardness) by the flexural elastic modulus (MPa).

3. The golf ball resin composition according to claim 1 , wherein the slab hardness of the golf ball resin composition ranges from 45 to 61 in Shore D hardness.

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

5. The golf ball resin composition 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 (a total of the (A) component, the (B) component and the (C) component is 100).

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

7. The golf ball resin composition according to claim 1 , wherein the flexural elastic modulus of the golf ball resin composition is 235 MPa or less.

8. The golf ball resin composition according to claim 1 , wherein a flexural elastic modulus of the (C) thermoplastic elastomer ranges from 1 MPa to 160 MPa.

9. The golf ball resin composition according to claim 1 , wherein a slab hardness of the (C) thermoplastic elastomer ranges from 3 to 50 in Shore D hardness.

10. A golf ball comprising

a core, at least one intermediate layer covering the core, and a cover covering the intermediate layer,

wherein at least one member of the core, at least one intermediate layer and the cover is formed from a golf ball 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, wherein the slab hardness of the golf ball resin composition is 61 or less in Shore D hardness.

11. The golf ball according to claim 10 , wherein a ratio (slab hardness×flexural elastic modulus/content of (A) component) is 1050 or less,

the ratio (slab hardness×flexural elastic modulus/content of (A) component) is obtained by dividing a product (slab hardness×flexural elastic modulus) by a content (mass %) of the (A) component in the resin component of the golf ball resin composition, and

the product (slab hardness×flexural elastic modulus) is obtained by multiplying the slab hardness (Shore D hardness) by the flexural elastic modulus (MPa).

12. The golf ball according to claim 10 , wherein the slab hardness of the golf ball resin composition ranges from 45 to 61 in Shore D hardness.

13. The golf ball according to claim 10 , wherein the flexural elastic modulus of the golf ball resin composition ranges from 130 MPa to 400 MPa.

14. The golf ball according to claim 10 ,

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, and

wherein the (A) component, the (B) component and the (C) component total is set as 100.

15. The golf ball according to claim 10 , wherein the (C) component contains a styrene-based thermoplastic elastomer.

16. The golf ball according to claim 10 , wherein the intermediate layer is formed from the golf ball resin composition.

17. The golf ball according to claim 16 , wherein the intermediate layer has a thickness in a range from 0.5 mm to 3.0 mm.

18. The golf ball according to claim 10 , wherein the cover has a slab hardness in a range from 50 to 70 in Shore D hardness.

19. The golf ball according to claim 10 , wherein the cover has a flexural elastic modulus in a range from 120 MPa to 450 MPa.

20. The golf ball according to claim 10 , wherein the cover has a thickness in a range from 0.3 mm to 4.0 mm.

21. The golf ball according to claim 16 , wherein a hardness difference (cover resin composition−intermediate layer resin composition) between a slab hardness of a cover resin composition for forming the cover and a slab hardness of an intermediate layer resin composition for forming the intermediate layer ranges from 0 to 15 in Shore D hardness.

22. The golf ball according to claim 10 , wherein the ratio (flexural elastic modulus/slab hardness) ranges from 3 to 4.5.

23. The golf ball according to claim 11 , wherein the ratio (slab hardness×flexural elastic modulus/content of (A) component) is 100 or more.

24. The golf ball according to claim 10 , wherein the flexural elastic modulus of the golf ball resin composition is 235 MPa or less.

25. The golf ball according to claim 10 , wherein a flexural elastic modulus of the (C) thermoplastic elastomer ranges from 1 MPa to 160 MPa.

26. The golf ball according to claim 10 , wherein a slab hardness of the (C) thermoplastic elastomer ranges from 3 to 50 in Shore D hardness.