Image forming apparatus

An image forming apparatus comprising:

• a rotatable endless belt configured to convey a toner image;
• a plurality of stretching rollers including an inner roller configured to stretch the belt;
• an outer member contacting an outer peripheral surface of the belt and configured to form a transfer portion, in cooperation with the inner roller, where the toner image is transferred from the belt onto a recording material;
• a position changing mechanism configured to change a position of the transfer portion with respect to a circumferential direction of the inner roller by changing a position of at least one of the inner roller and the outer member;
• an acquiring portion configured to acquire information on whether or not the recording material onto which the toner image is transferred is embossed paper;
• and
• a controller configured to control the position changing mechanism on the basis of the information,
• wherein in a cross section perpendicular to a rotational axis direction of the inner roller, when
• a tangential line common to the inner roller and an upstream roller on a side where the belt is stretched is defined as a first reference line,
• a rectilinear line passing through a rotation center of the inner roller and perpendicular to the first reference line is defined as a second reference line,
• a rectilinear line passing through a rotation center of the outer member and perpendicular to the first reference line is defined as a third reference line, and
• a distance between the second reference line and the third reference line is defined as an offset amount which is positive value when the third reference line is positioned on a side upstream of the second reference line with respect to a rotational direction of the belt,
• the controller is constituted so as to be capable of changing the offset amount on the basis of the information.