| 摘要 |
PURPOSE:To form a distinct image by using carbon black of which average grain diameter in a specified range is different from that for toner in starting developer and for replenishing toner. CONSTITUTION:When the average grain diameter of the carbon black in the toner in the starting developer is Amu and that in the replenishing toner is Bmu, the carbon black is selected so that 1.1<=A/B<=2.0, and the toner in the staring developer and the replenishing toner are produced. Therefore, an image of high density can be attained since an initial stage, without occurrence of toner scattering nor base fogging, which may be caused by carbon black aggregated by replenishing toner immediately after replenished. Thus, an distinct image of high density can be formed. |
