| 摘要 |
PURPOSE:To enable registration to be performed accurately without spoiling a picture pattern during rapid multi-color printing process by printing a registration mark on an ink printed part of a multi-color printed picture pattern, then printing the mark blank during ink printing and printing data using different primary colors one over the other. CONSTITUTION:A registration mark(a) is printed, for example, on the borderline of a highlighted black projecting part of a multi-colored picture pattern printed on a sheet or a folding book(c). Then a registration work is performed with a concurrent work, for example, to apply colors indigo, red and yellow to the registration marks sequentially. Subsequently, the registration marks(a) are blank at the point of time when the sheet is printed in black. Next, if colors black and indigo are supplied, the registration marks(a) are printed appearing indigo. Thus an irregular interval in the peripheral direction under a state where a blank part remains and a misalignment in the axial direction can be easily detected using a sensor so that an accurate registration to the black part is ensured. |
