Patent ID: 7303488

Claim:
A hollow golf club head comprising: a face portion having a front face that defines a club face for hitting a ball; a crown portion intersecting the club face at the upper edge thereof; and a sole portion intersecting the club face at the lower edge thereof, wherein the crown portion is provided along the front edge thereof with a face-backing zone in which the rigidity is gradually increased from its toe-side end and heel-side end toward the center thereof by changing the thickness in the face-backing zone such that the thickness is gradually increased from the toe-side end and heel-side end toward the center thereof, and the maximum thickness t 1 occurring in the increased-thickness central part is in a range of not less than 0.6 mm and not more than 2.0 mm, and a minimum thickness t 2 and a minimum thickness t 3 occurring on the toe-side and the heel-side, respectively, of the increased-thickness central part are in a range of not less than 0.5 mm and not more-than 1.5 mm.