| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of suppressing a flushing phenomenon and capable of very accurately controlling the amount of a toner supplied to a developing unit. <P>SOLUTION: The image forming apparatus has a powder conveying device comprising at least a powder container and a powder conveying means which rotates relatively to the powder container, wherein the powder conveying means has the center of rotation near the axial center of the powder container, the space between the internal surface of the powder container and the powder conveying means is sealed by magnetic particles restrained by a magnetic field generating means and it is characterised in that the magnetic particles have a saturation magnetization σs of 30.0-80.0 (Am<SP>2</SP>/kg), and when the residual magnetic flux density of the magnetic field generating means is represented by A (mT) and the intensity of magnetization of the magnetic particles in a magnetic field of residual magnetic flux density A (mT) by σ<SB>A</SB>(Am<SP>2</SP>/kg), A×σ<SB>A</SB>is equal to 3,000-35,000 (where A is in the range of 50-1,000 mT). <P>COPYRIGHT: (C)2005,JPO&NCIPI |
