| 摘要 |
A developing apparatus provided with a first developing member and a second developing member disposed on an upstream and downstream sides, respectively, and opposed to an image bearing member, and an applying device for applying a developing bias comprising a DC voltage and an AC voltage superimposed one upon the other to the first and second developing members to develop an electrostatic latent image on the image bearing member with a developer including a toner and a carrier, wherein the toner on the image bearing member is collected by the developing apparatus, and when the closest distance between the first developing member and the image bearing member is defined as SD 1 (m), and the closest distance between the second developing member and the image bearing member is defined as SD 2 (m), and the peak-to-peak voltage of the developing bias applied to the first developing member is defined as V 1 (V), and the peak-to-peak voltage of the developing bias applied to the second developing member is defined as V 2 (V), and the volume resistivity of the carrier is 1.0x10<SUP>x </SUP>Omega.cm, <?in-line-formulae description="In-line Formulae" end="lead"?>V 1/ SD 1- V 2/ SD 2 <=(0.65x-4.5)x10<SUP>6 </SUP>(V/m), <?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>1.2x10<SUP>6</SUP><=V 1/ SD 1 <=(0.35x+3.5)x10<SUP>6 </SUP>(V/m), <?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>(0.30x-1.5)x10<SUP>6</SUP><=V 2/ SD 2 <=9.0x10<SUP>6 </SUP>(V/m), and <?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>9.0<=X<=13.0 <?in-line-formulae description="In-line Formulae" end="tail"?> are satisfied.
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