DEVELOPING DEVICE AND IMAGE FORMING DEVICE

摘要

PURPOSE:To make thin line reproducibility and solid uniformity without scattering toner. CONSTITUTION:An electrostatic latent image is formed on a photosensitive drum 1 by an electrostatic charger 5 and a light emitting element 4. Toner is stuck by a coating roller 3c on a developing sleeve 2c which faces the photosensitive drum 1 and the toner layer thickness is restrained by a blade 7c. A developing bias power source 18 applies a bias voltage to the developing sleeve 2c to move the toner on the developing sleeve 2c to the photosensitive drum 1. At this time, the toner is scattered to stain a copy. When toner which is inferior in flowability is used so as to prevent the toner from being scattered, thin line restriction performance and solid uniformity deteriorates. For the purpose, toner which has a 3-30% degree of cohesion and 57-67 deg.C glass transition temperature is used to enable both prevention against scattering and improvement of quality.