IMAGE FORMING APPARATUS

To increase an ability to move a foreign substance to an upstream-side image carrier to reduce the amount of foreign substance moving to a downstream-side image carrier, thereby preventing an image defect caused by the foreign substance in association with the extension of life of units including the image carrier and a developing device.SOLUTION: An image forming apparatus 1 has a first image forming section PY, a second image forming section PM, a belt 12, an electrification voltage application section E1, and a transfer voltage application section E3. In the direction of movement of a recording material S, the first image forming section PY is arranged upstream of the second image forming section PM. In an image forming operation, the potential difference between a first transfer voltage and a potential at which an image formed on a first image carrier 4Y in a first transfer section NY is not formed, is larger than the potential difference between a second transfer voltage and a potential at which an image formed on a second image carrier 4M in a second transfer section NM is not formed.SELECTED DRAWING: Figure 5 【課題】上流側の像担持体に異物を移動させる能力をあげて、下流側の像担持体に移動する異物の量を低減することにより、像担持体や現像装置を含むユニットなどの長寿命化に伴う異物に起因する画像不良を抑制する。【解決手段】画像形成装置１は、第１の画像形成部ＰＹと、第２の画像形成部ＰＭと、ベルト１２と、帯電電圧印加部Ｅ１と、転写電圧印加部Ｅ３と、を有し、記録材Ｓの移動方向において、第１の画像形成部ＰＹは、第２の画像形成部ＰＭよりも上流に配置されており、画像形成動作において、第１の転写部ＮＹにおける第１の像担持体４Ｙに形成された画像を形成しない電位と第１の転写電圧との間の電位差は、第２の転写部ＮＭにおける第２の像担持体４Ｍに形成された画像を形成しない電位と第２の転写電圧との間の電位差よりも大きい構成とする。【選択図】図５