Golf ball

1. A golf ball comprising a core and a cover covering the core,

wherein the cover is formed from a cover composition containing,

a non-petroleum based polyester resin (A-1),

at least one petroleum based thermoplastic resin (A-2) selected from a binary copolymer composed of ethylene and an α,β-unsaturated carboxylic acid, a ternary copolymer composed of ethylene, an α,β-unsaturated carboxylic acid, and an α,β-unsaturated carboxylic acid ester, and their metal salt, as a resin component (A), and

a compatibilizer (C) containing at least a (meth)acrylic type resin (C-1) having a polar functional group and an olefin type resin (C-2) having a polar functional group,

wherein the non-petroleum based polyester resin contains a dicarboxylic acid, a diol and/or a hydroxycarboxylic acid as a constituent component, and at least one of the dicarboxylic acid, the diol and/or the hydroxycarboxylic acid is a non-petroleum based material,

wherein the (meth)acrylic type resin (C-1) is (i) a polymer of a polar functional group containing (meth) acrylic type monomer alone, (ii) a copolymer having an olefin content of less than 50% by mass in the copolymer of a polar functional group-containing (meth)acrylic type monomer and a (meth)acrylic type monomer having no polar functional group and/or a monomer other than (meth)acrylic type monomer, or (iii) a copolymer of a (meth)acrylic type monomer having no polar functional group and a polar functional group-containing monomer other than (meth)acrylic type monomer, and

wherein the olefin type resin (C-2) is a copolymer of an olefin and a polar functional group-containing monomer, in which the content of the olefin in the copolymer is 50% by mass or higher.

2. The golf ball according to claim 1 , wherein the polar functional group of the (meth)acrylic type resin (C-1) contained in the compatibilizer (C) is at least one selected from the group consisting of a glycidyl group, a hydroxyl group, a carboxyl group, an amino group, an imino group, a sulfone group, a nitro group, and an aldehyde group.

3. The golf ball according to claim 1 , wherein the polar functional group of the olefin type resin (C-2) contained in the compatibilizer (C) is at least one selected from the group consisting of a glycidyl group, a hydroxyl group, a carboxyl group, an amino group, an imino group, a sulfone group, a nitro group, and an aldehyde group.

4. The golf ball according to claim 1 , wherein the (meth)acrylic type resin (C-1) of the compatibilizer is a methyl methacrylate-glycidyl methacrylate copolymer, and the olefin type resin (C-2) is an ethylene-glycidyl methacrylate copolymer.

5. The golf ball according to claim 1 , wherein the compatibilizer (C) contains the (meth)acrylic type resin (C-1) and the olefin type resin (C-2) in a ratio (meth)acrylic type resin (C-1)/olefin type resin (C-2)) of 0.1 to 8.

6. The golf ball according to claim 1 , wherein the resin component (A) contains the non-petroleum based polyester resin (A-1) and the petroleum based thermoplastic resin (A-2) in a ratio of the non-petroleum based polyester resin (A-1)/the petroleum based thermoplastic resin (A-2)=50 parts to 95 parts by mass)/5 parts to 50 parts by mass, and the cover composition contains the compatibilizer (C) in an amount of from 1 part to 30 parts by mass with respect to 100 parts by mass of the resin component (A).

7. The golf ball according to claim 1 , wherein the cover composition contains at least two petroleum based thermoplastic resins (A-2) selected from a binary copolymer composed of ethylene and an α,β-unsaturated carboxylic acid, a ternary copolymer composed of ethylene, an α,β-unsaturated carboxylic acid, and an α,β-unsaturated carboxylic acid ester, and their metal salt, as a resin component (A).

8. The golf ball according to claim 7 , wherein the resin component (A) contains the non-petroleum based polyester resin (A-1) and the petroleum based thermoplastic resin (A-2) in a ratio of the non-petroleum based polyester resin (A-1)/the petroleum based thermoplastic resin (A-2)=50 parts to 95 parts by mass)/5 parts to 50 parts by mass, and the cover composition contains the compatibilizer (C) in an amount of from 1 part to 30 parts by mass with respect to 100 parts by mass of the resin component (A).

9. The golf ball according to claim 8 , wherein the compatibilizer (C) contains a methyl methacrylate-glycidyl methacrylate copolymer as the (meth)acrylic type resin (C-1) and an ethylene-glycidyl methacrylate copolymer as the olefin type resin (C-2) in a ratio (meth)acrylic type resin (c-1)/olefin type resin (c-2)) of 0.1 to 8.

10. The golf ball according to claim 9 , wherein the non-petroleum based polyester resin includes a polybutylene succinate adipate whose succinic acid component is a non-petroleum based material.

11. The golf ball according to claim 9 , wherein the non-petroleum based polyester resin includes a polybutylene succinate whose succinic acid component is a non-petroleum based material.

12. The golf ball according to claim 1 , wherein the cover composition has a slab hardness ranging from 40 to 70 in Shore D hardness.

13. The golf ball according to claim 1 , wherein the cover composition has a bending rigidity ranging from 200 MPa to 600 MPa.

14. The golf ball according to claim 1 , wherein the cover composition has a resilience of 55% or more.

15. The golf ball according to claim 1 , wherein the cover composition has a melt flow rate (190° C., 2.16 kg) ranging from 1 g/10 min to 10 g/10 min.

16. The golf ball according to claim 1 , wherein

the dicarboxylic acid is succinic acid, adipic acid, fumaric acid, maleic acid or pyruvic acid,

the diol is 1,4-butanediol, 1,3-propanediol or ethylene glycol, and

the hydroxycarboxylic acid is lactic acid, hydroxy acetic acid, hydracrylic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycyclohexane carboxylic acid, salicylic acid, hydroxybenzoic acid, and hydroxy toluic acid.