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:
Oct. 26, 1993
Filed:
Jun. 24, 1991
Albrecht Koller, Munich, DE;
Hans-Heinrich Credner, Hohenschaeftlarn, DE;
BASF Magnetics GmbH, Mannheim, DE;
Abstract
It has been found that a magnetic tape which may be used in particular for video recording and which has excellent abrasive and cleaning properties for all those parts of the cassette or rather the recording and play-back unit which come into contact with the magnetic layer can be obtained by addition of a non-magnetic powder having a Mohs' hardness of at least 9 and a primary particle size of 0.3 to 2 .mu.m to the magnetic pigment, which has a BET surface of at least 26 m.sup.2 /g, in the magnetic dispersion, the magnetic layer of the magnetic tape having an Ra value of less than 0.02 .mu.m. The best results were obtained with cubic Al.sub.2 O.sub.3 particles added in a quantity of 1.1 to 4.4% by weight, based on the magnetic pigment.