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:
Mar. 28, 1989
Filed:
Dec. 18, 1987
Hajime Machida, Tokyo, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A hexagonal ferrite element comprising a hexagonal ferrite film layer and a substrate for supporting the ferrite layer is prepared by applying on the substrate a metal-ion solution comprising an iron (II) ion and at least one ion selected from the group consisting of Ba.sup.2+, Sr.sup.2+, Pb.sup.2+, La.sup.3+ and Ca.sup.2+, with the pH of the solution set at 7 or more, thereby oxidizing the iron (II) ion contained in the metal-ion solution to iron (III) ion. For controlling the magneto-optical characteristics of the produced hexagonal ferrite film, other ions such as Co.sup.2+, Co.sup.3+, Al.sup.3+, In.sup.3+ and Ti.sup.4+ may be added to the above metal ion solution, thereby replacing part of iron atoms contained in the ferrite film by such atoms added in the form of ion. Further, for a more controlled and efficient production of the ferrite film, an oxidizing liquid for oxidizing the iron ion, Fe.sup.2+, contained in the metal-ion solution, to Fe.sup.3+ can be used by supplying the oxidizing liquid to the substrate concurrently with or after the application of the metal ion solution.