| 摘要 |
PURPOSE:To contrive a continuously vignetting printing devoid of halftone dots, by a method wherein the quantity of an ink supplied to a form cylinder by an ink-supplying mechanism is previously regulated. CONSTITUTION:This method can be carried out by a planographic offset press or other similar printing press, provided that the quantity of an ink supplied to the form cylinder in the press can be regulated along the longitudinal direction of the cylinder. For instance, the gap between a duct roller and a blade is regulated by rotating an adjusting screw so that the gap is gradually reduced in the direction from one end toward the other end, whereby the ink is supplied in a quantity proportional to the size of the gap. When printing is conducted by using the form cylinder supplied with the ink in this manner, a printed matter continuously shaded off from one end (where the density is higher) toward the other end (where the density if lower) can be obtained. In addition, a printed matter vignetted with a desired density gradient can be produced by varying the manner of regulating the gap between the duct roller and the blade. |
