MULTI-PIECE GOLF BALL, METHOD OF MANUFACTURING THE SAME, AND MOLDING DIE USED FOR MANUFACTURING THE SAME

摘要

The present invention provides a multi-piece golf ball comprising a core 3, a first intermediate layer 5, a second intermediate layer 7, and a cover 9, wherein the first intermediate layer 5 comprises a plurality of ribs 51 formed on the core 3; the second intermediate layer 7 is placed in concave portions surrounded by the ribs 51; and the cover 9 forms an outermost layer; with each of the ribs extending so that its width increases from the cover side to the core side; the concave portions being shaped into a funnel-like form by the side surfaces of the ribs; the hardness of the core 3, the first intermediate layer 5 and the second intermediate layer 7 being different from each other; and the hardness of the first intermediate layer 5 being greater than that of the second intermediate layer 9. <IMAGE>