Golf ball

Abstract

A golf ball can include a core, a mid layer, and a cover. The golf ball can satisfy the following mathematical formulas (1) and (2), ( Fa/Fan )≤0.90  (1), ( Fa/Fan ) 2 /( Fp/Fpn )≤0.90  (2), wherein Fa represents a maximum vertical force of the golf ball measured under a first condition. Fan represents a maximum vertical force of a standard ball measured under the first condition, Fp represents a maximum vertical force of the golf ball measured under a second condition, and Fpn represents a maximum vertical force of the standard ball measured under the second condition.

What is claimed is: 
     
         1 . A golf ball comprising a core, a mid layer positioned outside the core, and a cover positioned outside the mid layer, the golf ball satisfying the following mathematical formulas (1) and (2),
   ( Fa/Fan )≤0.90  (1),
     ( Fa/Fan ) 2 /( Fp/Fpn )≤0.90  (2),
   wherein Fa represents a maximum vertical force of the golf ball measured under a first condition, Fan represents a maximum vertical force of a standard ball measured under the first condition, Fp represents a maximum vertical force of the golf ball measured under a second condition, and Fpn represents a maximum vertical force of the standard ball measured under the second condition.   
     
     
         2 . The golf ball according to  claim 1 , wherein the golf ball satisfies the mathematical formula (3),
   ( Fp/Fpn )≤0.98  (3).
   
     
     
         3 . The golf ball according to  claim 1 , wherein the golf ball satisfies the mathematical formula (4),
   ( Tp/Tpn )≥1.01  (4),
   wherein Tp represents a contact time of the golf ball measured under the second condition, and Tpn represents a contact time of the standard ball measured under the second condition.   
     
     
         4 . The golf ball according to  claim 3 , wherein the golf ball satisfies the mathematical formula (5),
   ( Fp/Fpn )/( Tp/Tpn )≤0.93  (5).
   
     
     
         5 . The golf ball according to  claim 1 , wherein an amount of compressive deformation CD of the golf ball measured under a condition that an initial load is 98 N and a final load is 1275 N is not less than 3.00 nm. 
     
     
         6 . The golf ball according to  claim 1 , wherein a surface hardness H2s (Shore C) of the mid layer is greater than a surface hardness H1s (Shore C) of the core and is greater than a surface hardness H3s (Shore C) of the cover. 
     
     
         7 . The golf ball according to  claim 1 , wherein a difference (H1s−H1o) between a surface hardness H1s (Shore C) and a central hardness H1o (Shore C) of the core is not less than 14. 
     
     
         8 . The golf ball according to  claim 1 , wherein a ratio of a sum (T2+T3) of a thickness T2 of the mid layer and a thickness T3 of the cover to a diameter D1 of the core is not greater than 0.042. 
     
     
         9 . The golf ball according to  claim 1 , wherein a ratio (H2/H3) of a hardness H2 (Shore D) of the mid layer to a hardness H3 (Shore D) of the cover is not less than 1.80. 
     
     
         10 . The golf ball according to  claim 1 , further comprising one or more paint layers positioned outside the cover, wherein
 an indentation depth of an outermost paint layer when a load is 30 mgf is not less than 300 nm and not greater than 3000 nm.