1. Field of the Invention
The present invention relates to an image forming system comprised of an image forming apparatus that forms an image on a sheet, and a clear coating apparatus connected to the image forming apparatus on a downstream side of the same so as to perform clear coating on the sheet using clear toner which becomes clear (transparent) after being fixed on the sheet.
2. Description of the Related Art
In recent years, there has been an increasing demand for full-color electrophotographic image forming apparatuses ensuring high image quality. Further, it has been increasingly desired to realize a high-quality photographic tone image mode in an electrophotographic image forming apparatus, with proliferation of digital cameras as a major reason.
Further, there has been proposed an image forming system that is comprised of an image forming apparatus and a clear coating apparatus continuously connected thereto, and is configured to form a high-quality photographic tone image on a sheet, and then place thereon a toner image which becomes transparent when fixed, to thereby perform clear coating on the formed image (see e.g. Japanese Laid-Open Patent Publication (Kokai) No. H03-13079).
Further, there has been a system including apparatuses continuously connected to each other, in which an upstream one of the continuously connected apparatuses performs printing on a first surface of a sheet, and a downstream one of the apparatuses performs printing on a second surface of the sheet, to thereby realize double-sided printing without the provision of a sheet-inverting mechanism (see e.g. Japanese Laid-Open Patent Publication (Kokai) No. 2003-207954).
The above system with the continuously connected apparatuses is aimed at improving productivity, and hence double-sided printing is not performed within any of the apparatuses. Therefore, when the upstream one of the apparatuses performs double-sided printing on each sheet and discharges the sheet, according to a conventional job sequence, if the downstream one of the apparatuses also perform double-sided printing on the sheet, this causes the problem of an improper page order of the discharged printed sheets.