IMAGE FORMING DEVICE

To provide an image forming device capable of suppressing occurrence of poor image quality by forming an appropriate electrified state of a developer.SOLUTION: A developer support body includes at least a substrate, and a surface layer. The surface layer includes: a charge donating part for mainly donating charge to developer when giving and receiving charge by friction between the developer and the surface layer (A); and a charge reception part for receiving charge mainly from developer when giving and receiving charge by friction between the developer and the surface layer. When a detection part for detecting a state in which an image forming device is used detects a predetermined state, a control part increases the absolute value of a potential difference between an image support body and a developer support body as compared with that before detection of a predetermined state at predetermined timing.SELECTED DRAWING: Figure 1 【課題】現像剤の適正な帯電状態を形成し、画像不良の発生を抑制することができる画像形成装置を提供する。【解決手段】現像剤担持体は、少なくとも、基体、表面層を有しており、表面層は、（Ａ）現像剤と表面層とが摩擦することで電荷を授受する際に、現像剤へ電荷を主に与える電荷供与部と、（Ｂ）現像剤と表面層とが摩擦することで電荷を授受する際に、現像剤から主に電荷を受け取る電荷受容部と、を有し、画像形成装置が使用されている状態を検知する検知部が所定の状態を検知すると、制御部が、所定のタイミングで、像担持体と現像剤担持体と間の電位差の絶対値を、所定の状態が検知される前より大きくする。【選択図】図１