IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD

PROBLEM TO BE SOLVED: To realize high image quality by restraining toner scattering on the upstream side of a transfer part, in an image forming apparatus such as a copying machine, a printer, a facsimile and a plotter or the like and an image forming method. SOLUTION: Conductive members 70Y, 70C, 70M and 70Bk for applying bias having the same polarity as the electrification polarity of a photoreceptor 40 to an intermediate transfer belt 10 are provided inside the belt 10 on the upstream side of the transfer part of respective image forming means 18Y, 18C, 18M and 18Bk in the moving direction of the belt 10, and counter bias power sources are provided in accordance with the conductive members 70Y, 70C, 70M and 70Bk individually. Surface electrometers 71Y, 71C, 71M and 71Bk for detecting the surface potential of a reference toner pattern image formed on the photoreceptor 40 are provided near the surface of the photoreceptor 40, and the electrification amount of toner per unit area is calculated on the basis of the detected values of the surface elements 71Y, 71C, 71M and 71Bk. Then, a control means not shown in the figure controls the counter bias power source on the basis of the calculated value. COPYRIGHT: (C)2005,JPO&NCIPI