Solid golf ball

Abstract

In a solid golf ball comprising a solid core and a cover, provided that a coefficient of restitution at a firing velocity of v m/s is designated by CORv, a ball structure prior to formation of the cover satisfies COR25-COR50≧0.100, and the ball satisfies COR50≧0.740 and COR25-COR50≧0.09. The golf ball's performance depends little on the head speed so that the flight performance of the ball when hit at a low head speed is improved while the flight performance when hit at a high head speed is little deteriorated.

1 . A solid golf ball comprising a solid core and a cover, the improvement wherein provided that a coefficient of restitution at a firing velocity of v m/s is designated by CORv, a ball structure prior to formation of the cover satisfies COR25-COR50≧0.100, and the ball satisfies COR50≧0.740 and COR25-COR50 ≧0.09.  
     
     
         2 . The solid golf ball of  claim 1  wherein the ball structure prior to formation of the cover undergoes a deflection of 2.8 to 5.0 mm under an applied load of 100 kg.  
     
     
         3 . The solid golf ball of  claim 1  wherein the cover is formed of such a material that the Shore D hardness of the cover is not greater than 327.61X+27.239 wherein X represents (COR25-COR50) of the ball structure prior to formation of the cover.  
     
     
         4 . The solid golf ball of  claim 1  wherein the cover has a gage of 1.2 to 3.0 mm.  
     
     
         5 . The solid golf ball of  claim 1  having a contact area of 5.0 to 6.5 cm 2  when fired at a firing velocity of 50 m/s.