An object of the present invention is to provide a golf ball having a polyurethane cover, which is in excellent in abrasion resistance and durability without lowering the productivity. The present invention provides 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 containing a polyol having an unsaturated carbon-carbon bond as a constituent, and a crosslinking agent.
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 containing a polybutadiene polyol having an unsaturated carbon-carbon bond as a constituent and a crosslinking agent, the content of the polybutadiene polyol having the unsaturated carbon-carbon bond is from 5% to 60% by mole based on a total amount of polyol components constituting the thermoplastic polyurethane, and the number of the unsaturated carbon-carbon bonds per unit mass in the thermoplastic polyurethane before crosslinking with the crosslinking agent is 0.3×10 −3 mol/g or more and less than 7.9×10 −3 mol/g.
2. The golf ball according to claim 1 , wherein the cover composition contains 0.05 part to 5 parts by weight of the crosslinking agent with respect to 100 parts by weight of the thermoplastic polyurethane.
3. The golf ball according to claim 2 , wherein the crosslinking agent is a radical polymerization initiator.
4. The golf ball according to claim 3 , wherein the radical polymerization initiator is an organic peroxide or an azo compound.
5. The golf ball according to claim 4 , wherein the radical polymerization initiator has 10-hour half-life temperature of 60° C. or more.
6. The golf ball according to claim 5 , wherein the cover composition further contain a co-crosslinking agent.
7. The golf ball according to claim 1 , wherein the content of the polybutadiene polyol is from 10% to 55% by mole based on a total amount of polyol components constituting the thermoplastic polyurethane.
8. The golf ball according to claim 1 , wherein the content of the polybutadiene polyol is from 15% to 50% by mole based on a total amount of polyol components constituting the thermoplastic polyurethane.