An object of the present invention is to provide a golf ball which has excellent durability and wear-resistance and provides an excellent shot feeling. The present invention is directed to a golf ball comprising: a core; and a cover covering the core, wherein the cover is formed from a cover composition containing a thermoplastic polyurethane (A), a polyisocyanate (B) having at least two isocyanate groups, and a polyhydroxyether (C) as a resin component, and wherein the core has a surface hardness of 85 or smaller in JIS-C hardness.
1. A golf ball comprising:
a core; and
a cover covering the core,
wherein the cover is formed from a cover composition containing a thermoplastic polyurethane (A), a polyisocyanate (B) having at least two isocyanate groups, and a polyhydroxyether (C) as a resin component,
wherein the core has a surface hardness of 85 or smaller in JIS-C hardness, and wherein the polyhydroxyether (C) has a repeating structural unit represented by Formula (1):
wherein R 1 and R 2 are the same or different from each other, and each are a hydrogen atom or a methyl group.
2. The golf ball according to claim 1 , wherein the polyhydroxyether (C) has a number average molecular weight in a range from 100 to 100,000.
3. The golf ball according to claim 1 , wherein the polyhydroxyether (C) is an epoxy resin having an epoxy equivalent ranging from 1,000 g/eq to 20,000 g/eq.
4. The golf ball according to claim 1 , wherein the polyhydroxyether (C) is an epoxy resin having a number average molecular weight ranging from 1,000 to 8,000.
5. The golf ball according to claim 1 , wherein the polyhydroxyether is a phenoxy resin having a weight average molecular weight ranging from 10,000 to 100,000.
6. The golf ball according to claim 1 , wherein a content of the polyhydroxyether (C) is 1 to 20 parts by mass with respect to 100 parts by mass of the thermoplastic polyurethane (A).
7. The golf ball according to claim 1 , wherein the polyisocyanate (B) is a polyisocyanate mixture (B+b) where the polyisocyanate (B) is dispersed into a thermoplastic resin (b) which does not substantially react with an isocyanate group.
8. The golf ball according to claim 1 , wherein the cover composition contains the polyisocyanate mixture (B+b) in an amount from 1 part to 20 parts with respect to 100 parts of the thermoplastic polyurethane (A) by mass.
9. The golf ball according to claim 1 , wherein a difference (D 1 −D 2 ) between a compression deformation amount D 1 of the core and a compression deformation amount D 2 of the golf ball ranges from 0 mm to 0.4 mm.
10. A golf ball comprising:
a core; and
a cover covering the core,
wherein the cover is formed from a cover composition containing a thermoplastic polyurethane (A), a polyisocyanate (B) having at least two isocyanate groups, and a polyhydroxyether (C) represented by the following formula(2) as a resin component, and
wherein the core has a surface hardness of 85 or smaller in JIS-C hardness
wherein R 3 , R 4 , R 5 , R 6 are the same or different from each other, and each are a hydrogen atom or a methyl group; X and Y are the same or different from each other, and each are an epoxy group or a hydroxyethyl group; and n is a positive integer.
11. The golf ball according to claim 10 , wherein the polyhydroxyether (C) has a number average molecular weight ranging from 100 to 100,000.
12. The golf ball according to claim 11 , wherein the polyhydroxyether (C) is an epoxy resin having an epoxy equivalent ranging from 1,000 g/eq to 20,000 g/eq.
13. The golf ball according to claim 11 , wherein the polyhydroxyether (C) is an epoxy resin having a number average molecular weight ranging from 1,000 to 8,000.
14. The golf ball according to claim 11 , wherein the polyhydroxyether is a phenoxy resin having a weight average molecular weight ranging from 10,000 to 100,000.
15. The golf ball according to claim 11 , wherein a content of the polyhydroxyether (C) is 1 to 20 parts by mass with respect to 100 parts by mass of the thermoplastic polyurethane (A).
16. The golf ball according to claim 15 , wherein the polyisocyanate (B) is a polyisocyanate mixture (B+b) where the polyisocyanate (B) is dispersed into a thermoplastic resin (b) which does not substantially react with an isocyanate group.
17. The golf ball according to claim 16 , wherein the cover composition contains the polyisocyanate mixture (B+b) in an amount from 1 part to 20 parts with respect to 100 parts of the thermoplastic polyurethane (A) by mass.
18. The golf ball according to claim 17 , wherein a difference (D 1 −D 2 ) between a compression deformation amount D 1 of the core and a compression deformation amount D 2 of the golf ball ranges from 0 mm to 0.4 mm.