| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a dry toner which always has a stable charge amt. without producing a toner with the opposite polarity. SOLUTION: This toner contains a polyimide powder having about <=6μm average particle size and about 1×10<10> to 1×10<13>Ωcm electric resistance which is internally added. Since the average particle size (about <=6μm) is smaller than the average particle size (about 5 to 20μm) of the dry toner, the polyimide powder which is highly electrified into negative charges can be uniformly dispersed in the dry toner and prevents generation of a toner with the opposite polarity. Thereby, no fog is produced, uniform electrification is obtd, and stable image density is obtd. Since the electric resistance is large as about 1×10<10> to 1×10<13>Ωcm, the charge amt. can be always stabilized without depending on environmental conditions such as temp. and humidity, and therefore, gradation in the image density is prevented.</p> |
