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:
Dec. 21, 1993
Filed:
Jul. 14, 1992
Nobuaki Kawano, Higashiosaka, JP;
Nobuyuki Tsuji, Kakogawa, JP;
Takatomo Fukumoto, Osaka, JP;
Kaoru Tanaka, Daito, JP;
Masanori Fujii, Sakai, JP;
Atsushi Yamaguchi, Nara, JP;
Kazuhiko Fujii, Nara, JP;
Koji Okuda, Hirakata, JP;
Mita Industrial Co., Ltd., , JP;
Abstract
In accordance with the present invention, the electrophotographic toner is produced by dispersing and mixing toner components containing a fixing resin, a coloring agent and an electric charge controlling dye, and by melting and kneading the resulting mixture, which is then subjected to pulverizing and classifying. According to the present invention, fine powder generated at the pulverizing and classifying steps is reused as added to a mixture of toner components as already dispersed and mixed at the dispersing and mixing step, and the surface dye density of the electric charge controlling dye is in the range from 1.0.times.10.sup.-3 to 1.7.times.10.sup.-3 g/g, or the rate of the amount of an electric charge controlling dye present on the surfaces of toner particles to the total amount of the electric charge controlling dye, is in the range from 10 to 27% by weight. Even though repeatedly used for a long period of time, the electrophotographic toner does not lower the developer in electric charging characteristics. Further, by adding the fine powder to the mixture as already dispersed and mixed at the dispersing and mixing step, there can be efficiently produced a fine-powder regenerated toner excellent in transfer efficiency, resolution and gradation.