The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 28, 2000
Filed:
Jul. 31, 1998
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A press-molding die can manufacture magnetic disks suitable for the zone-texture technique in large quantities and at a low price by forming smooth surface areas and rough surface areas on the surface of the press-molding die. A manufacturing method for this press-molding die is provided. A magnetic-disk glass substrate that has improved CSS properties and allows a lower flying height is formed using this press-molding die. An intermediate layer is formed by sputtering on a die base material. A mask having an aperture is formed on the intermediate layer. The surface of the intermediate layer is roughened by etching in the aperture. A first protective layer is formed by sputtering in the etched portion. After the mask has been removed, a second protective layer is formed on the intermediate layer by sputtering. The surface roughness of the rough surface portion is reflected by the surface roughness of the first protective layer. The surface roughness if the first protective layer is reflected by the surface roughness of the second protective layer. Thus, a rough surface portion can be formed on the second protective layer.