IMAGE FORMING DEVICE

To provide an image forming device capable of reducing the difference between gloss of a toner image on a first surface of and gloss of a toner image on a second surface, in comparison to an arrangement where a recording medium with a toner image transferred to the second surface thereof is heated by a preheating unit to raise temperature of the first surface of the recording medium to a toner softening point or higher before heating the recording medium with a main heating unit.SOLUTION: A preheating unit is disposed between a transfer unit and a main heating unit in a recording medium conveying direction, and is configured to heat a recording medium with a toner image transferred onto a second surface thereof such that temperature of a first surface of the recording medium is kept lower than a toner softening point before heating the recording medium with the main heating unit.SELECTED DRAWING: Figure 1 【課題】第二面にトナー画像が転写された記録媒体を予備加熱部が加熱することで、本加熱部が記録媒体を加熱する前に記録媒体の第一面の温度がトナーの軟化点以上になる場合と比して、第一面のトナー画像の光沢度と第二面のトナー画像の光沢度との差を小さくすることができる画像形成装置を得る。【解決手段】予備加熱部は、記録媒体の搬送方向において転写部と本加熱部との間に配置され、第二面にトナー画像が転写された記録媒体を加熱するときに、本加熱部で記録媒体が加熱される前に記録媒体の第一面の温度がトナーの軟化点未満となるように記録媒体を加熱する。【選択図】図１