Image forming apparatus and image forming method with paper heating control

An image forming apparatus comprising:

• an image former that forms a toner image on paper;
• a fixing device that fixes by heat the toner image formed on the paper by the image former;
• an image forming path along which the paper is conveyed to the image former and the fixing device;
• a reverse path that (i) diverges from the image forming path on a downstream side of the fixing device in a paper conveying direction and (ii) meets the image forming path on an upstream side of the image former in the paper conveying direction so as to circulate the paper such that an image forming side of the paper is changed to an opposite side;
• and
• a hardware processor that performs paper heating control to (i) make the paper pass through the heated fixing device without image forming on the paper, thereby heating the paper, and (ii) re-convey the paper via the reverse path to the image former to perform image forming on the opposite side.

An image forming method for an image forming apparatus including:

• an image former that forms a toner image on paper;
• a fixing device that fixes by heat the toner image formed on the paper by the image former;
• an image forming path along which the paper is conveyed to the image former and the fixing device;
• a circulation path that (i) diverges from the image forming path on a downstream side of the fixing device in a paper conveying direction and (ii) meets the image forming path on an upstream side of the image former in the paper conveying direction so as to circulate the paper such that an image forming side of the paper is unchanged;
• and
• a hardware processor, the image forming method comprising:
• with the processor,
• performing paper heating control to (i) make the paper pass through the heated fixing device without image forming on the paper, thereby heating the paper, and (ii) re-convey the paper via the circulation path to the image former.

An image forming method for an image forming apparatus including:

• an image former that forms a toner image on paper;
• a fixing device that fixes by heat the toner image formed on the paper by the image former;
• an
• image forming path along which the paper is conveyed to the image former and the fixing device;
• a reverse path that (i) diverges from the image forming path on a downstream side of the fixing device in a paper conveying direction and (ii) meets the image forming path on an upstream side of the image former in the paper conveying direction so as to circulate the paper such that an image forming side of the paper is changed to an opposite side;
• and
• a hardware processor, the image forming method comprising:
• with the processor, performing paper heating control to (i) make the paper pass through the heated fixing device without image forming on the paper, thereby heating the paper, and (ii) re-convey the heated paper via the reverse path to the image former to perform image forming on the opposite side.