Patent ID: 7826758
Filing Date: 2010-11-02
Classification: G03G

Abstract:
1. An image forming apparatus comprising: an image bearing member; and a developer carrying member which carries a developer including a toner and a carrier, the developer carrying member developing with the developer an electrostatic image formed on the image bearing member, the developer carrying member being applied with alternating voltage so that an alternating electric field is formed between the developer carrying member and the image bearing member, wherein, in a graph whose axis of abscissa illustrates an electric field intensity to which the carrier is subjected and whose axis of ordinate illustrates a permittivity of the carrier, when: a slope of the graph at an electric field intensity Ed=|(Vp a slope of the graph at an electric field intensity Eb=|(Vp−VL)/X| is given as K a relation |K VL represents a potential [V] of the electrostatic image at which a maximum density is obtained; Vp Vp X represents a closest distance [m] between the image bearing member and the developer carrying member, and wherein the carrier comprises a porous core filled with a resin.