An object of the present invention is to improve the abrasion resistance of a golf ball that uses a polyurethane as a resin component for a cover. Another object of the present invention is to improve the shot feeling of a golf ball that uses a polyurethane as a resin component for a cover. The present invention provides a golf ball comprising a core; and a cover covering the core, wherein the cover contains a polyurethane elastomer as a resin component, and the polyurethane elastomer contains a polyol component and a polyisocyanate component and does not contain a chain extender.
1. A golf ball comprising
a core; and
a cover covering the core, wherein
the cover contains a polyurethane elastomer as a resin component, and the polyurethane elastomer contains a polyol component and a polyisocyanate component and does not contain a chain extender,
wherein the polyol component contains a hard polyol; and a soft polyol that does not have any one of a carbonate group, a ring structure, and an unsaturated bond in a main chain thereof, and
wherein the hard polyol is a polycarbonate polyol represented by the following Formula (1):
wherein R 1 denotes a divalent hydrocarbon group having an alicyclic structure or an aromatic ring structure in the main chain, and n denotes a natural number.
2. The golf ball according to claim 1 , wherein the soft polyol is a polyether polyol.
3. The golf ball according to claim 1 , wherein R 1 is a divalent hydrocarbon group having 6 to 10 carbon atoms with an alicyclic structure in a main chain thereof.
4. The golf ball according to claim 1 , wherein R 1 is 1,4-cyclohexanedimethylene group.
5. The golf ball according to claim 1 , wherein R 1 is a divalent hydrocarbon group having 12 to 20 carbon atoms with an aromatic ring in a main chain thereof.
6. The golf ball according to claim 1 , wherein R 1 is a phenylene group.
7. The golf ball according to claim 1 , wherein the soft polyol is a compound represented by the following Formula (2):
[In Formula (2), R 2 denotes a divalent saturated hydrocarbon group, and n denotes a natural number.].
8. The golf ball according to claim 7 , wherein R 2 is a divalent hydrocarbon group having 3 to 6 carbon atoms with a side chain.
9. The golf ball according to claim 1 , wherein a mass ratio (hard polyol/soft polyol) of the hard polyol to the soft polyol falls within a range from 3/7 to 7/3.
10. The golf ball according to claim 1 , wherein a mass ratio (hard polyol/soft polyol) of the hard polyol to the soft polyol falls within a range from 3/7 to 5/5.
11. The golf ball according to claim 1 , wherein the polyisocyanate component is 4,4′-diphenylmethane diisocyanate.
12. The golf ball according to claim 1 , wherein the cover has a hardness ranging from 20 to 50 in Shore D hardness.
13. The golf ball according to claim 1 , wherein the polyol component has a number average molecular weight ranging from 400 to 10,000.
14. The golf ball according to claim 1 , wherein the polyol component has a hydroxyl value (mgKOH/g) of 500 or less.
15. The golf ball according to claim 1 , wherein a molar ratio (NCO/OH) of an isocyanate group contained in the polyisocyanate component to a hydroxyl group contained in the polyol component ranges from 1.00 to 1.10.
16. The golf ball according to claim 1 , wherein the cover has a thickness ranging from 0.3 mm to 1.0 mm.
17. The golf ball according to claim 1 , wherein the core has a hardness difference ranging from 10 to 40 in JIS-C hardness between a surface hardness and a center hardness thereof.
18. A golf ball comprising
a core; and
a cover covering the core and having a slab hardness ranging from 20 to 50 in Shore D hardness,
wherein the cover contains, as a resin component, a polyurethane elastomer essentially consisting of a high-molecular weight polyol component having a number average molecular weight ranging from 400 to 10,000 and a polyisocyanate component;
wherein the high-molecular weight polyol component contains a hard polyol; and a soft polyol that does not have any one of a carbonate group, a ring structure, and an unsaturated bond in a main chain thereof, in a mass ratio of the hard polyol to the soft polyol being from 3/7 to 7/3, and
wherein the hard polyol is a polycarbonate polyol represented by the following Formula (1):
wherein R 1 denotes a divalent hydrocarbon group having an alicyclic structure or an aromatic ring structure in the main chain, and n denotes a natural number.