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. 02, 1999
Filed:
Feb. 25, 1997
Masahisa Ochiai, Fukaya, JP;
Masumi Asanae, Kumagaya, JP;
Tsutomu Saitoh, Kumagaya, JP;
Takashi Hayano, Honjo, JP;
Hitachi Metals, Ltd., Tokyo, JP;
Abstract
An Li--Mn ferrite carrier comprising 2 to 15 mol % of Li.sub.2 O, 5 to 30 mol % of MnO and 60 to 90 mol % of Fe.sub.2 O.sub.3. The carrier may contain at least one sintering aid selected from the group consisting of CaO, Na.sub.2 O, SiO.sub.2, V.sub.2 O.sub.5, Al.sub.2 O.sub.3, As.sub.2 O.sub.3, Bi.sub.2 O.sub.3, Sb.sub.2 O.sub.3 and B.sub.2 O.sub.3 to improve the surface properties thereof. The carrier may be made sensitive to the intensity of electric field by regulating the specific volume resistivities at 200 V/cm and 10 kV/cm within the specific ranges. This carrier is particularly suitable in the reversal developing method, and in the developing method where an A.C. bias voltage is superimposed to a D.C. bias voltage.