| 摘要 |
<p>PURPOSE:To conduct a stabilized image forming system by specifying the molar ratio of a bivalent metal ion among the elements constituting a ferrous magnetic substance dispersed in a toner to the trivalent iron. CONSTITUTION:A toner thin layer 8a is always in contact with a Latent image face on a photosensitive body 1 in this developing device of contact development system, and hence a generated reverse-polarity toner is adhered to the surface and the non-picture part before and behind the formed image, and the charge amt. of the thin layer 8a should be most strictly controlled. Accordingly, the molar ratio of the bivalent metal ion among the elements constituting the ferrous magnetic substance dispersed in the toner to the trivalent iron is controlled to <=1/3, and one-component magnetic toner material useful in contact development system is obtained in this way. Further, the molar ratio is preferably controlled to <=0.25 when the metal ion is iron ion. Consequently, the amt. of recovered toner is increased.</p> |
