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. 17, 1987
Filed:
Feb. 28, 1985
Mikihiko Kato, Kanagawa, JP;
Yasutoshi Okuzawa, Kanagawa, JP;
Shigeo Komine, Kanagawa, JP;
Kazuhiko Morita, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A flexible magnetic disk in which the friction between the magnetic sheet of the disk and a positioning member is reduced, the magnetic sheet is positioned properly and without offset each time it is loaded in a reading/reproducing device, and the tracking accuracy and dimensional accuracy are satisfactory. A protective layer is provided around the periphery of a central hole in the magnetic sheet. The protective layer is made of a composition containing a compound which has an acrylic or methacrylic acid ester bond at one or both of a main chain terminal and a side chain thereof. The compound is one which is cured by radiation. The thickness of the protective layer should be 30 microns or less, and the surface irregularity of the protective layer should be 0.03 microns or more represented in terms of a central line average roughness at a cutoff of 2.5 mm.