The common square and circular dots in offset printing are arranged perpendicular to each other in the structure, and dot angles can be represented by 0°-90°. In multi-color printing, dots with more than two colors are superimposed on one another. Dots of different colors intersect each other at different angles. The smaller the angle of intersection is, the larger the pattern is, and the larger pattern will destroy the original tone of the image. When the intersection angle is large, the pattern is small, and the influence on the reproduction of the tone is small.
Under normal circumstances, when the intersection angle of the dots is 30°, the pattern presented is more appropriate. Yellow and light colors because of poor color rendering, sometimes the intersection angle can be smaller.
In the four-color printing process, there are four commonly used dot angles: 15°, 45°, 75°, and 90°. The main color tone of the picture is 45°, and the yellow color is 90°.
In spot color printing, monochromatic lithography or monochromatic gradation is superimposed on the field version, and the 45° angle in the gradation version is generally more beautiful; two different color superimposed versions are used, usually in 45° and 90° angles; A different color of superimposed version of superimposition, usually using 30 °, 60 °, 90 ° angle.
â—Ž China Design Printing Network