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:
May. 04, 2021
Filed:
Jan. 15, 2018
Applicant:
Powdertech Co., Ltd., Kawasaki, JP;
Inventors:
Hiroki Sawamoto, Kashiwa, JP;
Tetsuya Uemura, Kashiwa, JP;
Assignee:
POWDERTECH CO., LTD., Kashiwa, JP;
Primary Examiner:
Int. Cl.
CPC ...
G03G 9/00 (2006.01); G03G 9/107 (2006.01); G03G 9/083 (2006.01); G03G 9/113 (2006.01); H01F 1/11 (2006.01);
U.S. Cl.
CPC ...
G03G 9/107 (2013.01); G03G 9/0837 (2013.01); G03G 9/113 (2013.01); H01F 1/11 (2013.01);
Abstract
A magnetic core material for electrophotographic developer, satisfying a value of Expression (1): a+b×10+c+d+e+f, being from 200 to 1,400, when an amount of fluorine ion is denoted by a (ppm), an amount of chlorine ion is denoted by b (ppm), an amount of bromide ion is denoted by c (ppm), an amount of nitrite ion is denoted by d (ppm), an amount of nitrate ion is denoted by e (ppm), and an amount of sulfate ion is denoted by f (ppm), which are measured by combustion ion chromatography; and having a pore volume of from 30 to 100 mm/g.