Image forming apparatus having control based on detected toner charge and transfer efficiency

摘要

An image forming apparatus has an image bearing member; a toner image forming device for forming a toner image on the image bearing member; a transfer charger for transferring the toner image from the image bearing member onto a transfer material; a first detector for detecting toner charge amount before image transfer onto the transfer material; a second detector for detecting the efficiency of the image transfer; and a controller for controlling a condition of image transfer operation in accordance with outputs of the first and second detector.