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:
May. 11, 1993
Filed:
Jul. 25, 1991
Applicant:
Inventors:
Noboru Tsuya, Tokyo, JP;
Tadao Tokushima, Hamamatsu-shi, Shizuoka-ken, JP;
Toshiro Takahashi, Hamamatsu-shi, Shizuoka-ken, JP;
Assignee:
Other;
Primary Examiner:
Int. Cl.
CPC ...
C25D / ; B05D / ; B05D / ;
U.S. Cl.
CPC ...
205162 ; 427129 ; 205223 ;
Abstract
This invention relates to a process for preparing a magnetic disk, which comprises (a) subjecting a substrate having an anodized aluminum film to mirror surface-finishing, (b) widening pores of the anodized aluminum film by chemical dissolution treatment so that the total area of pores becomes from 20 to 80% of the entire surface area, thereby retaining crystalline alumina of the anodized aluminum film extruded after the chemical dissolution treatment, and (c) coating the resultant substrate with a magnetic continuous thin film.