| 摘要 |
PURPOSE:To obtain a uniform triboelectricity characteristic, and to apply uniformly a toner to a carrier by constituting so that the surface of a member for giving a triboelectrification charge to the toner contains a fine powder having a prescribed electrostatic charge quantity. CONSTITUTION:A fine powder having an electrostatic charge quantity B given by 1/40<¦B¦/¦A¦<1/2, ¦A¦>¦B¦ is contained in the surface of a non-magnetic cylinder 4b for giving a triboelectrification charge to a magnetic toner 11. In this regard, A denotes an electrostatic charge quantity of the insulating toner 11. When an electrostatic image holding surface 1 rotates in the direction as indicated with an arrow, since a multi-polar permanent magnet 9 is fixed, the toner 11 fed from a developing vessel 12 is applied onto the cylinder surface by rotating the non-magnetic cylinder 4b in the same direction as the electrostatic image holding surface 1, also the toner 11 is charged electrostatically uniformly in the polarity opposite to the electrostatic image charge by a friction against the cylinder surface, and the toner 11 is applied uniformly to the electrostatic image holding surface 1. |
