| 摘要 |
<P>PROBLEM TO BE SOLVED: To surely prevent a stain from being made on printed matter, without relying on the level of skill of an operator. <P>SOLUTION: A DSP (color-mixture halftone density detecting means) 11 determines a color-mixture halftone density of a non-printing area, corresponding to a gap part of a blanket cylinder, of the printed matter, and that of a non-image area in a printing area of the printing matter by using an IRGB densitometer 1. After that, a stain density of the non-image area with respect to the non-printing area is determined from the color-mixture halftone density of the non-printing area and that of the non-image area by using a color conversion part 14. An increase in dampening water for each ink color, corresponding to the stain density, is determined according to a corresponding relationship between a preset stain density and a preset increase in dampening water, by using a dampening water supply computing part 40. A target dampening water supply, wherein the increase in the dampening water is added to the present dampening water supply, is determined, and the dampening water supply is adjusted by a control device 20, so as to reach the target dampening water supply. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
