PURPOSE: To hold an ozone eliminating function in a constant state by applying a decomposing agent or an absorbing agent of an ozone to a member in a device, so that discharge gas containing an ozone generated in the deivce passes through the applied part.

CONSTITUTION: This device is constituted so that an agent or an absorbing agent of a new ozone is replaced automatically, when replacing a member to be replaced after it has been used for a prescribed period, such as a photosensitive body, a replenishing toner vessel, a waste toner vessel, etc. provided in the device, without using an ozone filter. That is to say, an electrostatic charger 2, a developing device 3, a transfer charger 4 and a cleaning device 5 are provided on the outside circumference of a photosensitive drum 1, and an ozone decomposing paint 8 is applied to the inside wall of a case 6 of the developing device 3 and a case 7 of the cleaning device 5. According, an ozone generated by the charger 2 and the transfer charger 4 is decomposed by the ozone decomposing paint 8, discharge of the ozone to the outside of a machine and a bad influence to the photosensitive drum 1 due to the ozone are prevented, and the cases 6, 7 are replaced by about 2,000 sheets together with a life of the photosensitive drum 1, therefore, the ozone eliminating function of a constant level is always maintained.