| 摘要 |
<p>PURPOSE: To provide a developer which contain specific toner and specific carrier so as to have a satisfactory chargeabilty with no control agent, which scatters little toner and which is excellent in picture quality. CONSTITUTION: A binary system developer contains toner and carrier. The toner particles contain fixing resin and magnetic powder dispersed in the resin. The fixing resin contains resin having an anionic polar group. The magnetic powder contained in the toner has 0.1 to 5 weight parts with respect to 100 weight part of the fixing resin. The toner particles has a volumetric reference particle size of 5 to 15μm, and are stuck at the outer surface thereof with first and second spacer particles having a particle size of 0.05 to 1μm and specific resistance of 10<1> to 10<5>Ωcm, 10<8> to 10<13>Ωcm, respectively. Each carrier particle has a core particle and a cover layer. The core particle is made of a magnetic material exhibited as M0Fe2 O3 (where M is metal such as Cu or Zu). The cover layer contains alkylated melamine resin and acrylic denatured silicone resin, the alkylated melamine resin having a mean molecular weight M which is exhibited by M>=1100C-400 (where C is carbon number in the alkyl group).</p> |
