PURPOSE: To obtain an excellent image without reversal fogging by increasing a chance to bring the developer electrostatically charged to have a reverse polarity into contact with the surface of a developer carrier at the abutting part of a developer regulating member on the developer carrier and realizing normally electrostatically charging the developer.
CONSTITUTION: A developing blade 1 is provided with a soft nonconductive elastic member 1a, a conductive layer 1b laminated and supported on the member 1a, and a dielectric layer 1c arranged on an opposed surface to a developing sleeve 3. By setting an electric field generating means and impressing voltage on the conductive layer 1b, the electric field E is pulsatively generated so that force attracting the normally electrostatically charged toner T1 to the surface of the blade 1 may act at the nip 4 of the abutting part. Since the blade 1 has soft elasticity, the toner T is not in a packing state at the nip 4, and the chance to bring the reversal toner T2 into contact with the surface of the sleeve 3 by the force caused by the pulsatively imparted electric field E is increased, then the reversal toner T2 is normal electrostatically charged and reduced.
SAKAIZAWA KATSUHIRO
OSHIMA MASAKI
OGAWA KIYONARI
