Image forming method and image forming apparatus.

摘要

An image forming apparatus is formed by disposing a latent image-bearing member (1) for holding an electrostatic image thereon and a toner-carrying member (22) for carrying a magnetic toner with a prescribed magnetic toner comprises a binder resin and magnetic powder and has a particle size distribution including 12 % by number or more of magnetic toner particles of 5 microns or smaller, 33 % by number or less of magnetic toner particles of 8 - 12.7 microns and 2 % by volume or less of magnetic toner particles of 16 microns or larger so as to provide a volume-average particle size of 4 - 10 microns. At the developing station, an alternating bias voltage comprising a DC voltage and an unsymmetrical AC voltage in superposition is applied between the toner-carrying member (22) and the latent image-bearing member (1) to provide an alternating bias electric field comprising a development-side voltage component and a reverse-development side voltage component. The development-side voltage component has a magnitude equal to or larger than that of the reverse development-side voltage component and a duration smaller than that of the reverse-development side voltage component, so that the magnetic toner on the toner-carrying member, particularly fine powdery fraction thereof effective for high-quality development, is effectively transferred to the latent image-bearing member to develop the electrostatic image thereon at the developing station.