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 ⅓ 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 {fraction (1/10)} to ½ times of the weight-average particle diameter of the magnetic carrier and a number of concavities which are 1 mum to 10 mum wide and 0.2 mum or more deep is smaller than 10 within a spacing of 100 mum in a surface profile of the developer carrying member.