Color image forming apparatus with toner recycling

1. Field of the Invention A color image forming apparatus includes a plurality of image forming sections independent of each other. The image forming sections store respective toner of different colors that are chargeable to the same polarity. All the toner are implemented by the same binder resin and provided with the same particle size distribution. Further, developing units each storing toner of particular color are identical in specification. When two-ingredient type developers are used, the developers contain an identical carrier. The apparatus recycles the toner of different colors to the respective developing units. The alien color toner collected in each developing unit is prevented from remaining by being chargeable to the same polarity.