| 摘要 |
PURPOSE:To provide the magnetic toner having synthetically excellent character- istic which obtains a high image density even low consumption without increasing the content of a magnetic fine powder, excellent in resolving power, dot reproducibility and thin line reproducibility and improves photosensitive environmental dependence, etc. CONSTITUTION:The toner is incorporated with at least magnetic fine powder and binding resin, and covered with the silica which is subjected to the treatment converting to hydrophobic in the surface, and is the small grain size magnetic toner having 4-9mum D50, and the content of the magnetic powder having 0.15-0.25mum grain size, 6-8m<2>/g BET and 7-10emu/g residual magnetization is 30-70%, and the toner has 10-40 MI and/or 30-60 muC (absolute) charge level, or the magnetic body has the above mentioned characteristic, and the content of the silica sticking weakly to the surface of the silica added is <=0.35% per the toner content, and the sum of the content of the silica sticking moderately to the surface of the silica and the content of the silica sticking weakly to the surface of the silica is >=0.25% per the toner content. |
