PURPOSE: To prevent the rear end of transfer material from flying up by the sucking force of an exhaust fan and damaging an image when the rear end of the transfer material is discharged to a separating part following to a trans ferring part.

CONSTITUTION: A transfer material detecting element 16 is installed following a destaticization needle 11, and a signal is inputted to a CPU 17 and the CPU 17 controls the exhaust fan 13. As for a control, (1) the exhaust fan is stopped when the detecting element 16 detects the front end of the transfer material and thereafter operates the exhaust fan when the rear end of the transfer material is detected. (2) The stop operation of the fan 13 is performed by respectively delaying time after the transfer material detecting element 16 respectively detects the front and the rear ends of the transfer material. (3) The transfer material detecting element 16 delays and stops the fan 13 after detecting the front end of the transfer material and operates the fan 13 after detecting the rear end of the transfer material. The rear end of the transfer material does not fly up by any of (1), (2) and (3) after the rear end of the transfer material passes the separating part.