Fuser

A fuser, comprising:

• a rotatable heating member in a form of a roll;
• a heater in a form of a board located inside the rotatable heating member, the heater having a first surface and a second surface opposite to the first surface in a thickness direction of the heater;
• a rotatable pressing member forming a nip in conjunction with the rotatable heating member, the rotatable pressing member being configured to convey a sheet in a conveying direction in conjunction with the rotatable heating member, the conveying direction intersecting orthogonally with a lengthwise direction of the heater and with the thickness direction of the heater;
• a heat-conductive member located between an inner circumferential surface of the rotatable heating member and the first surface of the heater in the thickness direction, the heat-conductive member nipping the rotatable heating member in conjunction with the rotatable pressing member;
• and
• a holder located inside the rotatable heating member, the holder supporting the heater,
• wherein a dimension of the heat-conductive member in the conveying direction is greater than a dimension of the heater in the conveying direction,
• wherein the holder comprises:
• a first holder surface extending in the conveying direction and supporting the second surface of the heater in the thickness direction;
• and
• a second holder surface located at least either upstream or downstream of the first holder surface in the conveying direction, the second holder surface facing the heat-conductive member, the second holder surface being located closer than the first holder surface to the heat-conductive member in the thickness direction, the first holder surface and the second holder surface being connected by a gap surface, and
• wherein a thickness of the heater is greater than a length of the gap surface in the thickness direction.