Image forming method and image forming apparatus

摘要

An electrostatic image supporting member which supports an electrostatic image and a toner carrying member for conveying a magnetic toner are disposed in a development section with a specified gap therebetween. The toner carrying member has a base whose surface has an average surface roughness (Ra) of 1.0 to 3.0 mu m. A resin coating containing electrically conductive fine particles is formed on the base surface at a density of 4 to 12 g per 1 m2. The outer layer of the coating has an Ra from 0.8 to 3.0 mu m. The toner carrying member carries an electrically insulating magnetic toner containing at least a binder resin and a magnetic component, and satisfying the conditions of a volumetric average particle size of 4.5 to 8 mu m, a BET specific surface area of 1.8 to 3.5 m2/g, a charge amount of -20 to -35 mu c/g, a loose-state apparent density of 0.40 to 0.52 g/cm3, and a true specific gravity of 1.45 to 1.8. The magnetic toner is formed into a layer having a thickness smaller than the dimension of the gap by a member for regulating the thickness by pressing the toner against the toner carrying member. The magnetic toner is then conveyed to the development section, in which the toner develops the electrostatic image while an AC electric field is applied.