Patent ID: 7187878

Claim:
An image forming apparatus comprising: an image forming unit configured to form a toner image on a printing material; a thermal fixing unit configured to have a rotating member incorporating a heating element and a pressurizing member which comes into contact with the rotating member and pressurizes the rotating member, convey a printing material on which a toner image is formed to a nip area between the rotating member and the pressurizing member, and fuse the toner image on the printing material by making the printing material pass through the nip area while applying heat from the heating element to the printing material; a temperature sensor configured to detect a temperature of the printing material which has passed through the nip area, wherein said temperature sensor is capable of detecting a temperature near said thermal fixing unit when the printing material does not pass through said thermal fixing unit; and a control unit configured to, when continuous printing operation is performed in which a plurality of printing materials are printed continuously, control an amount of heat supplied to a succeeding printing material on the basis of a first temperature detected by said temperature near said thermal fixing unit sensor at a time point before a first printing material is conveyed to the nip area in the continuous printing operation and a second temperature of the printing material that has passed through the nip area, detected by said temperature sensor at a predetermined time point during the continuous printing operation.