Patent ID: 6049687
Filing Date: 2000-04-11
Classification: G03G

Abstract:
A developing apparatus, comprising:a developer bearing member disposed in an opposed relationship with an image bearing member bearing an electrostatic image thereon with a gap of 6.times.10.sup.-4 m or less with respect to said image bearing member, and bearing and conveying a developer thereon, wherein said developer bearing member is moved in a direction opposing a direction of movement of said image bearing member in a portion opposed to said image bearing member, and the developer has a nonmagnetic toner and a carrier of which the magnetization rate in a magnetic field of 1000 gauss is equal to or greater than 30 emu/cm.sup.3 and equal to or less than 200 emu/cm.sup.3 and the specific resistance at electric field intensity of 5.times.10.sup.4 V/m is 10.sup.12 .OMEGA.cm or greater; andapplying means for applying a bias voltage having a vibration component to said developer bearing member, wherein the bias voltage applied to said developer bearing member and the gap between said image bearing member and said developer bearing member satisfy the following relation:2.0.times.10.sup.6 .ltoreq.V/d<4.0.times.10.sup.6,whereV is the amplitude (V) of the vibration component of the bias voltage;d is the size (m) of the gap between the image bearing member and the developer bearing member.