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:
Jun. 23, 1981
Filed:
Mar. 10, 1977
Eduard Schoenafinger, Jenesien, IT;
Herbert Motz, Ludwigshafen, DE;
Manfred Ohlinger, Frankenthal, DE;
Paul Deigner, Weisenheim, DE;
Werner Grau, Willstaett, DE;
BASF Aktiengesellschaft, , DE;
Abstract
Chromium dioxide magnetic pigments are stabilized against loss of their magnetic properties by treating them, in aqueous and/or alcoholic suspension, with a block copolymer consisting of siloxane units and alkyleneoxy units of 2 to 4 carbon atoms, the alkyleneoxy units being bonded to the polysiloxane radical by a Si--O--C or Si--C group, in an amount of from 1 to 40% by weight based on the chromium dioxide, after which the latter is separated off and dried at from 50.degree. to 200.degree. C. The stabilized chromium dioxide magnetic pigments may be used for the manufacture of magnetic recording media exhibiting improved stability of the magnetic properties under adverse climatic conditions.