METHOD FOR ELECTROFORMING ELECTROFORMED MASTER DISK AND ELECTROFORMED MASTER DISK

摘要

PURPOSE:To produce an electroformed master disk as an Ni master disk in a flaw-free state by attaching a conductive ring for electroforming to the outside periphery of an electroformed recording master disk and electrifying the recording surface of the recording master disk via the ring in an Ni plating bath at the time of producing an electroformed master disk to which an information recording master disk is transferred. CONSTITUTION:After an information 13 is cut by means of laser beam in a photoresist 4 applied to a glass plate 6 and a conductive film 5 is formed on the above by means of silver mirror reaction to form a photoresist master disk 10, Ni is electroformed to form an Ni master disk 1. A conductive ring 2 for electroforming having a diameter practically equal to that of the master disk 10 is placed on the outside periphery of the master disk 10, which is set in a member consisting of a cathode 8 and a presser part 7. The photoresist master disk 10 is immersed into an Ni plating bath and the conductive film 5 is electrified via a conductive plate 9 and the ring 2 to form an Ni electroformed layer 3, by which a pattern for the master disk 1 consisting of the electroformed layer 3 and the ring 2 is formed. Subsequently, the above pattern is taken out of the Ni plating bath and the surface of the Ni electroformed layer is polished, and then, the photoresist master disk 10 and the Ni electroformed layer 3 are peeled off, by which the Ni master disk 1 can he completed.