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:
Feb. 23, 1988
Filed:
Mar. 19, 1985
Tetsuo Oka, Otsu, JP;
Kenji Hayashi, Kyoto, JP;
Takayoshi Akamatsu, Otsu, JP;
Satoshi Horiuchi, Otsu, JP;
Toray Industries, Inc., Tokyo, JP;
Abstract
A vertical magnetic recording medium comprising a substrate and a magnetic layer formed on the substrate and having a magnetic anisotropy in the direction vertical to the surface of the substrate is described. The magnetic layer is composed substantially of a metal selected from cobalt and/or iron, and an oxide of the metal. The metal and metal oxide consist of columnar structures oriented in the direction vertical to the surface of the substrate and spaced from one another through fine voids throughout the magnetic layer. The columnar structures have a diameter of 100 to 1000 .ANG. and the magnetic layer have a void ratio of to 56%. The vertical magnetic recording medium is prepared by a process for vacuum-depositing a metal selected from cobalt and iron to form a magnetic layer on a substrate, wherein an oxygen gas and at least one gas chemically inactive in the vacuum deposition system, which is selected from nitrogen, argon, helium, neon, xenon, radon, methane and ethane, are introduced into the vacuum to an extent such that the pressure in the vicinity of the substrate is 1.times.10.sup.-3 to 5.times.10.sup.-2 Torr.