Developing apparatus

摘要

A developing apparatus for an image forming apparatus has means for forming an electrostatic latent image corresponding to an image information signal on an image bearing member having: a developer carrying member which bears and conveys a two-component developer containing a non-magnetic toner and a magnetic carrier for forming a toner image by developing the electrostatic latent image on the image bearing member. The convexities and concavities are formed on a surface of the developer carrying member, and an average peak-to-peak spacing (Sm) of the convexities and concavities is set at 1/3 to 6 times of a weight-average particle diameter of said magnetic carrier (D) (D/3 ≤ Sm ≤ 6*D), average roughness at ten points (Rz) on the surface of the developer carrying member is set at 1/10 to 1/2 times of the weight-average particle diameter of the magnetic carrier and a number of concavities which are 1 mu m to 10 mu m wide and 0.2 mu m or more deep is smaller than 10 within a spacing of 100 mu m in a surface profile of the developer carrying member. <IMAGE>