| 摘要 |
<p>A two-component developer suitable for electrophotography is formed of a toner and a resin-coated carrier. The resin-coated carrier is formed of carrier core particles and 0.01 - 2.0 wt. % based on the carrier core particles of a resin coating layer coating the carrier core particles. The resin-coated carrier has an average particle size of 25 - 55 mu m and the carrier core particles comprise a ferrite component represented by formula (I) below: (Fe2O3)a(MnO)b(MgO)c(A)d wherein A represents a mixture of SrO, CaO and Al2O3, and a, b, c and d are numbers representing mol fractions of associated components and satisfying: 0.4 < a < 0.6, 0.35 < b < 0.45, 0.07 < c < 0.12, 0.005 < d < 0.015, and a+b+c+d </= 1. Because of the specific composition, the carrier core particles are provided with a smooth surface, which is reflected into a surface smoothness of the resin-coated carrier even after coated with a thin resin coating layer. Accordingly, the resin-coated carrier is provided with a good balance among toner-charging ability, flowability and durability suitable for reproduction of an original having a large areal percentage.</p> |
