DISC FORMING DIE, DISC SUBSTRATE AND METHOD FOR FORMING THE DISC SUBSTRATE

摘要

An object is to enable a drive to stably support a disk and prevent occurrence of a data read error, a data write error, or a like error. A disk-molding mold comprises a first mirror-surface disk; a second mirror-surface disk; a stamper attached to one of the first and second mirror-surface disks; a first punching portion formed on the first mirror-surface disk; a second punching portion which is formed on the second mirror-surface disk and punches a disk substrate prototype when advanced; a stationary-side surrounding member which surrounds the first punching portion; and a movable-side surrounding member which surrounds the second punching portion. A projection portion (65) is formed on at least one of the surrounding members along an inner circumferential edge thereof such that the projection portion projects toward the other surrounding member. Even when a burr is formed on the side of a disk substrate on which an information surface is formed, the burr is formed to extend from the rear end toward the front end of the chamfered portion of the disk substrate.