Patent ID: 8204429

Claim:
An image forming apparatus configured to perform duplex printing, said image forming apparatus comprising: a recording head configured to discharge liquid droplets onto a sheet to form an image on the sheet; a conveying belt configured to electrostatically attract and convey the sheet to face the recording head; at least two rollers disposed so as to support the conveying belt; a pressing member opposing one of the at least two rollers that is provided upstream of the recording head in a sheet conveyance direction via the conveying belt to press the sheet against the conveying belt; a charger rotatably driven by the conveying belt to charge the conveying belt; a sheet discharge device provided downstream from the conveying belt in the sheet conveyance direction to convey the sheet in a sheet discharging direction, the sheet discharge device being intermittently driven independently of and in synchronization with the conveying belt; a duplex device configured to reverse and re-feed the sheet bearing the image formed on a first side thereof by the recording head to form an image on a second side of the sheet; and a voltage application device configured to apply a voltage to the charger, wherein a distance between the charger and a nip portion formed between the pressing member and the conveying belt is set and the voltage applied by the voltage application device to the charger is controlled so that for said duplex printing to a predetermined sheet and to a subsequent sheet, a magnitude of a charged potential in an area of the conveying belt electrostatically attracting a trailing end of a predetermined sheet on which an image is to be formed on a first side thereof and a leading end of a subsequent sheet on which an image is to be formed on a second side thereof is higher relative to a magnitude of a charged potential in an area of the conveying belt electrostatically attracting a portion between end portions of the predetermined sheet in the sheet conveyance direction, and wherein the image forming apparatus further comprises a controller configured to control drive of the conveying belt and control operations of the voltage application device and the charger, so that the magnitude of the charged potential of the conveying belt in the area electrostatically attracting the trailing end of the predetermined sheet and the leading end of the subsequent sheet is relatively higher than the magnitude of the charged potential in the area electrostatically attracting a leading end of the predetermined sheet.