Patent ID: 8059995
Filing Date: 2011-11-15
Classification: G03G

Abstract:
1. An image forming apparatus comprising: an image bearing member; and a developer bearing member bearing a developer including a toner and a carrier, the developer bearing member developing an electrostatic image formed on the image bearing member with the developer, and the developer bearing member being applied with an alternate voltage in order to form an alternate electric field between the developer bearing member and the image bearing member, wherein in a semi-logarithmic graph in which an abscissa axis represents an electric field intensity to be applied to the carrier, an ordinate axis represents a resistivity of the carrier on a logarithmic scale, letting electric field intensities Eb, Ed (where: VL is a potential [V] of the electrostatic image for obtaining the highest density; Vp Vp D is the closest distance [m] between the image bearing member and the developer bearing member), and letting a gradient at Ed equal K a resistivity ρb of the carrier at the electric field intensity Eb satisfies ρb<6.0×10 wherein satisfied are relationships of