Abstract: A developing apparatus includes a developing roller having a surface on which a layer of a non-magnetic single component developing agent (toner) is adapted to be formed, a toner supply roller held in contact with the developing roller so as to electrify the toner and also to supply the toner to the developing roller, and a toner regulating blade for regulating the toner on the developing roller so as to form a film of the toner thereon. The toner regulating blade is formed into a generally L-shape, and with a simple construction, the thickness of the toner layer, formed on the developing roller, can be stabilized, and also a torque of the developing roller can be reduced, and the degradation of a printed image is suppressed, thereby stabilizing the printed image.

Abstract: A nonmagnetic single component developing device comprises a developing roller having an outer surface on which a layer of a nonmagnetic single component developer composed of nonmagnetic toner is formed, a toner supply roller arranged in rear of the developing roller and made into contact therewith, for agitating and supplying the toner, a toner regulating blade arranged above the developing roller and made into press-contact therewith, for regulating a volume of the toner. The toner supply roller is electroconductive, and is applied thereto with an a.c. voltage so as to prevent lowering of the density in the leading and trailing end parts of an image so as to obtain a uniform image characteristic.

Abstract: A developing apparatus has a toner reservoir for holding a non-magnetic toner, a toner supply roller including a supply surface for receiving the toner from the toner reservoir and electrifying the toner thereon, an electrostatic latent image carrier including a curved or flat latent image surface on which a latent image formed by an electrostatic voltage distribution thereon is developed by the toner transferred from the supply surface, and a toner seal surface arranged adjacent to the toner supply roller to contact a remaining part of the toner on the supply surface after the latent image development so that the remaining part of the toner is taken into the toner reservoir. The respective frictional coefficients between the toner seal surface and the toner and between the toner particles are selected to prevent a disturbance of toner condition between the toner and the toner seal surface.