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.

Date of Patent:
Oct. 03, 2000

Filed:

Dec. 16, 1999
Applicant:
Inventors:

Tadao Sumiyoshi, Matsubara, JP;

Tomohide Iida, Osaka, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
430108 ; 4301066 ; 430111 ;
Abstract

A two-component-type developing agent comprising a silicone resin-coated carrier and a positively charging toner, the silicone coated carrier having an average particle diameter of from 60 to 110 .mu.m, the silicone resin coating having an average thickness of from 0.1 to 0.3 .mu.m, the carrier having a resistivity of from 1.5.times.10.sup.8 to 1.5.times.10.sup.11 .OMEGA..multidot.cm, the toner concentration being from 3.0 to 5.0 % by weight and the amount of electric charge by friction of the toner based on the suction method being from +10 to +20 .mu.c/g. The silicone resin-coated carrier and the developing agent feature long life without permitting the spent toner to adhere on the carrier surfaces, without permitting the carrier coating to peel off even after repetitively used for extended periods of time, featuring stable amount of electric charge by friction, stable developing properties, and maintaining favorable image quality for extended periods of time developing none of carrier dragging, toner scattering in the machine, background fogging or defective image density.


Find Patent Forward Citations

Loading…