Patent ID: 6947691
Filing Date: 2005-09-20
Classification: G03G

Abstract:
1. A development device comprising: An electrostatic transportation device which moves fine particles by an electrostatic force, said electrostatic transportation device comprising, wherein a width of each of the electrodes in a traveling direction of the fine particles is set to be in a range of 1 time to 20 times an average particle diameter of the fine particles, a pitch between the electrodes in the traveling direction of the fine particles is set to be in a range of 1 time to 20 times the average particle diameter of the fine particles, driving waveforms of n phases or more (n is an integer of 3 or more) are applied to respective electrodes, the transporting base plate has an inorganic or organic surface protective layer covering the electrodes, and the thickness of the surface protective layer does not exceed 10 μm; the surface protective layer comprises a single layer or a plurality of layers, at least the outermost layer of the surface protective layer provided on the transporting base plate is formed from a material positioned in the vicinity of a material used as a charge controlling agent of fine particles on a frictional charge sequence or a material positioned on a positive end side, and fine particles with a negatively charged polarity are moved.