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. 01, 1991
Filed:
Jan. 12, 1990
Helmut Bonnemann, Muheim an der Ruhr, DE;
Werner Brijoux, Muheim an der Ruhr, DE;
Rainer Brinkmann, Muheim an der Ruhr, DE;
Studiengesellschaft Kohle mbH, Mulheim an der Ruhr, DE;
Abstract
Disclosed is a process for preparing acicular non-sintered iron metal pigments for magnetic signal recording, having a high storage density, high saturation magnetization and remanence, the coercive field strength of which at a given crystallite size of the starting material is low and is increased as desired by subsequent annealing. The preparation of said iron metal pigments is effected by reduction of iron oxide compounds with metal hydrides of metals of the Groups I or II of the Periodic Table of Elements in organic solvents, with the metal hydrides being solvatized with a carrier in the form of a carrier complex.