WET-TYPE DEVELOPING UNIT CAPABLE OF REDUCING PRESSING POWER GIVEN TO SQUEEZE ROLLER AND CAPABLE OF CONTROLLING TONER DENSITY OF LIQUID DEVELOPER ADHERED ON DEVELOPMENT ROLLER

摘要

In a wet-type developing unit (300), a plating roller (400) is disposed parallel to a development roller (110) at a predetermined distance. The plating roller (400) is connected to a variable power source (402) controlled by a voltage controller (404). The plating roller (400) is supplied with a voltage from the variable power source (402) and has an electric potential higher than that of the development roller (110) to move charged particle toners included in a liquid developer film adhered on the development roller (110) toward the development roller (110). The plating roller (400) reduces thickness of the liquid developer film and increase a solid component ratio of the liquid developer film. When the solid component ratio is large, pressure given by a squeezed roller (118) can be smaller.