Patent ID: 7636100

Claim:
An image forming apparatus, comprising: an image bearing member configured to bear a toner image; a transfer unit mount portion configured to interchangeably mount a first transfer unit and a second transfer unit, said first transfer unit and said second transfer unit configured to transfer the toner image from said image bearing member onto a recording material, said first transfer unit and said second transfer unit being replaceable one for the other wherein said first transfer unit includes a first transfer member and said second transfer unit includes a second transfer member, when the image forming apparatus prints with said first transfer unit mounted on said transfer unit mount portion, a leading edge of the recording material to be conveyed to a transfer area comes in contact with said image bearing member after first coming in contact with said first transfer member, and when the image forming apparatus prints with said second transfer unit mounted on said transfer unit mount portion, the leading edge of the recording material to be conveyed to a transfer area is apart from said second transfer member after first coming in contact with said image bearing member; and a controller configured to have a margin-less print mode for forming the toner image onto the recording material without a margin on any one of edges of the recording material, and a normal print mode for forming the toner image onto the recording material to provide margins on all the edges of the recording material, wherein said controller makes it possible to carry out the margin-less print mode when said first transfer unit is mounted on the transfer unit mount portion, and makes it possible to carry out the normal print mode and inhibits carrying out the margin-less print mode when said second transfer unit is mounted on said transfer unit mount portion.