A golf ball providing rebound performance, spin performance, resistance to abrasion and anti-wearability in an excellent balance is formed of a core and a cover arranged to cover the core and formed mainly of diene rubber having a smaller trans structure content before it is crosslinked than after it is crosslinked, in particular by 2 to 20%. The diene rubber is preferably polybutadiene rubber and as the cover's co-crosslinking agent a metallic salt of α,β-ethylene unsaturated carboxylic acid is used.
1. A golf ball formed of a core and a cover arranged to cover said core, wherein said cover is formed mainly of diene rubber having a smaller trans structure content before said rubber is crosslinked than after said rubber is crosslinked, and
wherein said cover contains a ternary composite formed of a rubber component, a polyolefin component and a nylon component.
2. The golf ball of claim 1 , wherein said diene rubber is polybutadiene rubber.
3. The golf ball of claim 1 , wherein said cover contains a metallic salt of α,β-ethylene unsaturated carboxylic acid as a co-crosslinking agent.
4. The golf ball of claim 1 , wherein there is a difference (T 2 −T 1 ) of 2% to 20% between a trans structure content (T 2 ) of said diene rubber having been crosslinked and that (T 1 ) of said diene rubber having not yet crosslinked.
5. The golf ball of claim 2 , wherein said cover contains a metallic salt of α,β-ethylene unsaturated carboxylic acid as a co-crosslinking agent.
6. The golf ball of claim 1 , wherein the cover has a thickness of from 0.3 to 3 mm and a Shore D hardness of 46 to 58.
7. The golf ball of claim 6 , wherein the cover thickness is 0.5 to 2.5 mm.
8. The golf ball of claim 6 , wherein the cover thickness is 0.7 to 1.5 mm.
9. The golf ball of claim 6 , wherein the cover has a Shore D hardness of 48 to 54.
10. The golf ball of claim 4 , wherein the difference (T 2 −T 1 ) is 3% to 18%.
11. The golf ball of claim 4 , wherein the difference (T 2 −T 1 ) is 5% to 15%.
12. The golf ball of claim 4 , wherein the difference (T 2 −T 1 ) is 5% to 11%.