Patent ID: 7162193

Claim:
An image forming apparatus comprising: an image bearing body which forms an image by an electro-photographic method; an intermediate transfer belt which is rotated by a driving roller and transfers primarily the image on the image bearing body; and a mechanism for secondarily transferring the image on the intermediate transfer belt to a final transfer member, wherein the intermediate transfer belt has a multi-layered structure of at least an elastic layer on a substrate layer, and when a percentage difference of a stretched length of an outer circumference of the intermediate transfer belt to an inner circumference thereof at a position of contact to the driving roller is A % and a percent difference of a length of stretched side of the belt driven and stretched by the driving roller to a length of non-stretched opposite side of the belt is B %, the intermediate transfer belt is configured so that ranges of A and A+B fall simultaneously into inequalities of 1<A<6 and 3<A+B<10.