Patent ID: 6272306
Filing Date: 2001-08-07
Classification: G03G

Abstract:
A developing apparatus comprising:a developer bearing member for bearing and carrying developer to a developing area;developer borne on said developer bearing member, wherein said developer has a weight average particle size not exceeding 6.5 .mu.m and contains an external additive of a charging polarity opposite to that of said developer; andvoltage application means for applying a voltage to said developer bearing member, wherein said voltage including at least a first voltage V1 for acting on said developer in a direction from said developer bearing member toward an image bearing member and a second voltage V2 for acting on said developer in a direction from said image bearing member toward said developer bearing member, and a charged potential VL of said image bearing member, a latent image potential VD a distance H between said developer bearing member and said image bearing member, and wherein said voltages V1 and V2 satisfy a following relationships:.vertline.V1-VL.vertline./H.ltoreq.3.7.times.10.sup.-6 V/m; and.vertline.V2-VD.vertline./H.ltoreq.2.9.times.10.sup.-6 V/m.