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:
Apr. 04, 1978
Filed:
May. 16, 1977
Bayer Aktiengesellschaft, Leverkusen, DT;
Abstract
An Fe.sub.3 O.sub.4 iron oxide black pigment having incorporated therein up to about 50 mole percent of .gamma.-Fe.sub.2 O.sub.3 plus Me Fe.sub.2 O.sub.4 (wherein Me is at least one of magnesium, manganese, cobalt, nickel, aluminum, chromium, titanium, copper, zinc and cadmium) having a specific surface according to BET of greater than about 12 m.sup.2 /g, up to about 10% by weight of a substantially insoluble inorganic compound as coating and a stability to oxidation with air under standardized conditions of greater than about 130.degree. C. Advantageously the coating comprises at least one of zinc hydroxide, zinc phosphate, zinc phosphite, aluminum phosphate and silica, being precipitated onto the suspended pigment from a solution. The resulting pigments are of improved resistance to oxidation, rendering them especially useful for pigmenting inorganic and organic dispersions and for use on magnetogram supports.