ELECTROPHOTOGRAPHIC DEVELOPING DEVICE

摘要

PURPOSE: To provide an electrophotographic developing device maintaining the surface roughness of a developing roll to be constant with time or in the device life and to secure an excellent printing density for a long term. CONSTITUTION: As for the electrophotographic developing device 11 where the developing roll 21 is constituted by forming an elastic layer 23 on the outer peripheral surface of a core bar 29 and an electrostatic latent image on a photoreceptor 27 is developed by a thin layer toner 15 carried on the surface of the elastic layer 23 of the developing roll 21, the elastic layer 23 consists of a rubber elastic body material and is constituted by adding fine powder whose diameter is 1-50μm of electrically insulating material by 30-200 parts.