Patent ID: 7674188

Claim:
A golf club head comprising: a face; a plurality of score line grooves formed on the face; and a plurality of striations formed in the face by milling, wherein edges of each score line groove are rounded with a radius of not more than 0.2 mm, wherein a width W (mm) of the score line groove measured including the rounded edges and a width Ws (mm) representing a distance between adjacent score line grooves satisfy a first expression: S /( Wr× 0.5)×100≧70(%), and wherein a width Wr (mm) of the score line groove measured based on a 30 degrees measurement rule and a cross section area S (mm 2 ) of the score line grooves satisfy a second expression: W/Ws× 100≧35(%) wherein the face in which the striations are formed has an arithmetic mean deviation of a profile (Ra) of not less than 4.00 μm, and wherein each striation forms a circular arc, said striations are the only circular arcs on said face, said striations do not intersect with each other on said face, and each score line groove intersects with a plurality of said striations.