Method and apparatus for electroforming a stamper for producing a high-density information recording carrier
AssigneeDaicel Chemical Industries, Ltd.
InventorNorio Okabayashi
Life of this patent
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Abstract
Method and apparatus for producing a desired thickness distribution on a stamping plate in a rotary electroforming process. The stamping plate is used to produce a high density information recording carrier. A shielding plate is detachably mounted adjacent a fixed anode in an electrochemical bath. Another shielding plate is detachably mounted adjacent the rotary cathode. During electroforming either or both shielding plates are put into position or removed at appropriate times to produce the desired thickness distribution.
Claims4
A method for electroforming a stamper for producing a high-density information recording carrier by using a rotary electroforming apparatus having a fixed anode and a rotary cathode, the steps comprising removably mounting a shielding plate on the anode side of a clearance between said anode and said cathode, removably mounting a shielding plate on the cathode side of said clearance and, while electroforming a stamper in said apparatus is in progress, removing at least one of said removably mounted shielding plates thereby controlling the electroformed thickness distribution along a radial direction of the stamper to a desired value.
An apparatus for electroforming a stamper for producing a high-density information recording disc-including a fixed anode and a rotary cathode having a clearance therebetween, a shielding plate removably mounted on the anode side of said clearance for removal while electroforming is in progress and a shielding plate removably mounted on the cathode side of said clearance for removal while electroforming is in progress.
Dependencies are inferred from the claim text.