| 摘要 |
<p>PURPOSE:To prevent the nonuniformity of the density of an initial image and to obtain an excellent image without irregularities by uniformly imparting a triboelectrification charge to magnetic toner from a developer carrier surface layer whose surface has the formation of a conductive coating film layer. CONSTITUTION:A developing sleeve 4 whose surface has the formation of the conductive a coating film layer 4b obtained by compounding carbon black, etc., into binding resin is used for the magnetic toner 3 to form a grain layer 7 having solid lubricity on the surface of an elastic blade 6 and the average grain diameter L of the grain of the grain layer 7 is set larger than 10-points average roughness Rz on the surface of the developing sleeve 4. Thus, not only when the magnetic toner 3 is the toner of a normal grain diameter, but also even if the magnetic toner 3 is fine grain toner, a charge is uniformly imparted from the surface layer of the developing sleeve 4 to the magnetic toner 3 and the irregularities in the initial image can be prevented.</p> |
