PURPOSE: To prevent transfer material carrying speed from being decreased and to obtain an excellent image without the omission of character by providing a low fric tional member in a contact surface area between a carried transfer material and a member or an equipment materials coming into contact with the carried transfer material on the upstream side in a transfer material carrying direction from a transfer process part.

CONSTITUTION: Contact friction resistant force between the carried transfer material P and the member or the equipment materials with which the material P comes into contact is decreased by providing the low frictional member at least at a part of the contact surface area between the material P and the member or the equipment materials coming into contact with the material P on the upstream side in the transfer material carrying direction from the transfer process part N. Namely, the low frictional member is provided at the lower surface area of the bottom part 4a of a developing device 4 on the side of a processing cartridge 30 in contact with the upper surface of the material P with regard to the cartridge 30 of a miniaturized image forming device. The low frictional member is a material layer lowering a friction coefficient with the material P, and is the adhesive layer of 'Teflon(R)' tape (tetrafluoride ethylene resin tape), for instance, or the coating layer of such material.