Patent ID: 7933527

Claim:
An image forming apparatus, in which an electrostatic latent image formed on a surface of a photoreceptor is developed into a toner image with a developing device, and in which a printing paper transported on a transport belt is brought into contact with the surface of the photoreceptor and an electric field is applied to the printing paper from a rear surface of the transport belt by a transfer roller to transfer the toner image onto the printing paper, the transfer roller applying different levels of electric field to the printing paper, so that a predetermined transfer electric field is applied to a region other than a leading edge of the printing paper being transported, and that a weak electric field weaker than the predetermined transfer electric field is applied to the leading edge of the printing paper being transported, the weak electric field being set so that the printing paper naturally strips from the photoreceptor according to a transfer speed of the printing paper and curvature of the photoreceptor even in a case where the printing paper has a projection that is formed when the printing paper is cut and where the projection is formed at the leading edge of the printing paper and faces the transport belt, wherein the weak electric field is varied according to types of the printing paper, and wherein the weak electric field is weaker for a thick printing paper than for a thin printing paper, when a peripheral speed of the photoreceptor is equal to or greater than 500 mm/sec.