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:
Sep. 07, 1976
Filed:
Apr. 29, 1975
Ugo Montiglio, Alessandria, IT;
Giampiero Basile, Alessandria, IT;
Pierfrancesco Aspes, Alessandria, IT;
Elio Gallinotti, Alessandria, IT;
Montedison S.p.A., Milan, IT;
Abstract
Ferromagnetic chromium dioxide is prepared by thermally decomposing, at a temperature of 250.degree.-500.degree.C, and a pressure of at least 80 atmospheres, a mixture of hydrated trivalent chromium chromate of the formula Cr.sub.2 (CrO.sub.4).sub.3.nH.sub.2 O, wherein n is 7-12, and antimony or a compound thereof, the amount of antimony in the mixture being between 0.2 and 1.8% by weight based on the weight of anhydrous Cr.sub.2 (CrO.sub.4).sub.3. In another embodiment, other known modifiers for chromium dioxide, such as lanthanum, lithium, strontium, iron or lead, or a compound thereof may be added to the mixture of chromium chromate and antimony. The amount of said other modifiers is between 0.1 and 2% by weight of the element, based on the weight of anhydrous Cr.sub. 2 (CrO.sub.4).sub.3.