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:
Mar. 17, 1992
Filed:
Aug. 23, 1989
Michael W Mueller, Plankstadt, DE;
Ekkehard Schwab, Neustadt, DE;
Helmut Auweter, Limburgerhof, DE;
Rainer Feser, Gruenstadt, DE;
Werner Huebner, Frankenthal, DE;
Norbert Mueller, Friedelsheim, DE;
Manfred Ohlinger, Frankenthal, DE;
Hermann Dikow, Hockenheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A chromium dioxide material consisting of acicular, ferromagnetic chromium dioxide particles having a nonmagnetic, hydrogen-containing protective surface layer, which material has improved stability to chemical decomposition, a process for its preparation and magnetic recording media containing this chromium dioxide and having good long-term stability of the residual magnetization under conditions of high humidity and temperature are described.