| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain preferable results of the image density and fog from the initial stage of printing to long-term printing with 5000 sheets and to obtain preferable memory development in halftone originals and denseness of the picture quality by visual check. SOLUTION: The magnetic monocomponent developer is composed of toner particles (A) by 90 to 99 wt.% essentially comprising a binder resin and magnetic powder and of toner particles (B) by 1 to 10 wt.% essentially comprising a binder resin, magnetic powder and positive electrification type electrification controlling agent. The toner particles (A) do not contain an electrification controlling agent or contain a negative electrification controlling agent. Both of the toner particles (A) and (B) are subjected to the surface treatment with at least negative electrification hydrophobic silica.</p> |
