Detailed Prepress Operation - Separation Operation Paper 5

V. Press printing and color separation

Due to the strict time requirements, fast printing, and rough paper, press printing should pay attention to the following issues. (1) Press printing is mainly based on high-speed web printing, which requires that the amount of ink overprint should not be too high. UCR is required to control the maximum ink stacking volume at 240 to 260%, and the copy reproduction range should be limited to 8 to 85%. , (2) When using UCR should pay attention to the use of black version. (3) Press printing is usually very ink, easy to dirty, easy to infiltrate the solvent in the paper, which will reduce its luster, dark color, color separation should be as vivid as possible, saturated, as shown in Figure 6.14. (4) After UCR is used, intermediate tone should be increased as shown in Figure 6.15, UCR volume is controlled at 30-40%, and black platen value is 10%-20% lower than conventional color separation. (5) The color separation screen should be limited to 100L-150L/inch. (6) In the high light area, the C version should be enlarged, and the Y and M versions should be reduced. (7) The amount of USM for news print images should be 1-2 higher than the conventional separation.

(to be continued)