Patent ID: 8073369
Filing Date: 2011-12-06
Classification: G03G

Abstract:
1. A development device comprising: a binary developer composed of a magnetic carrier and a toner; a developing roller for applying the toner to an electrostatic latent image formed on a surface of an image carrying member so as to develop the electrostatic latent image, at least a surface layer of the developing roller being made of an elastic body; an intermediate roller made of metal and disposed closely to the developing roller so as to face the developing roller; and a magnetic roller disposed closely to the intermediate roller so as to face the intermediate roller; wherein: the magnetic roller is rotated in contact with the binary developer so that a developer layer made of a mixture of the magnetic carrier and the toner is formed on a surface of the magnetic roller; the developer layer is carried toward the intermediate roller made of metal so that only the toner of the developer layer is transferred to the intermediate roller so as to form a toner layer; and with rotation of the intermediate roller and the developing roller, the toner layer is transferred from the intermediate roller to the developing roller, and the toner layer on the developing roller is brought into contact with the surface of the image carrying member.