How to arrange the custom printing color sequence for printing and packaging? In color printing, how to reasonably arrange the order of overprinting of colors is an important subject studied by process technicians. An important role of printing is to artistically reproduce the original, which requires the printer to have a certain artistic appreciation and the ability to master the expressive ability of color changes. Improper color sequence arrangement may lead to color cast, color mixing and reverse overprinting of the printed matter; scientific color sequence arrangement will make the color of the printed matter closer to the original, and even strengthen a certain color atmosphere, so that the layers are clear, the dots are clear, and the overprinting is accurate. Colors are true, natural and harmonious.

There are three reasons why the color sequence needs to be arranged: the influence of the mutual overprinting of the ink and the shortcomings of the ink color material itself, the quality of the paper, and the ability of the human eye to recognize the color. The most fundamental reason is the incomplete transparency of the printing ink itself, that is, the covering power of the ink itself. The later printed ink has a certain covering effect on the first printed ink layer, so that the color presented by the printed matter is always focused on the expression of the latter color, or the mixed color of the later color and the previous color.

The starting point of selecting the color sequence is to arrange the color sequence flexibly according to the specific conditions of the manuscript, combined with the current process conditions, taking care of the main aspects (such as tone reproduction, color reproduction, graphic clarity, printing uniformity and printing repetition rate, etc.) .

There are the following principles for arranging color order:

1. Arrange the color sequence according to the content and characteristics of the manuscript. Printing is a means of expressing layout graphic design, and the emotional components reflected by each color are also different. Therefore, the arrangement of the color sequence must first consider the content and characteristics of the manuscript. When editors design the layout of graphics and text, they often have chosen the tone of the layout color. This tone is the overall feeling that represents the entire tone and becomes the dominant color in printing

. In terms of chromaticity, those based on red, orange and yellow are called warm colors; those based on green and blue are called cool colors. Due to the covering power of the ink, generally, the warm tone is mainly used to print black and cyan first, and then the magenta and yellow are printed; Everyone wants the flesh of a fully ripe watermelon to be red, and they don't want to see the purple or greenish color of the printed matter. Different color sequences have different color cast effects. Therefore, the colors that need to be strengthened in the color atmosphere of the picture can be printed in the last color.

2. Consider the nature of the paper to arrange the color sequence. For paper of poor quality, considering its low whiteness and smoothness, loose fibers, poor ink absorption, and easy to lose powder and hair, you can first print yellow ink to make up for the above defects of paper. When printing at night, due to the recognition power of the human eye, weak-color ink with low lightness should not be arranged in the first color printing. The order of brightness of ink is: white < yellow < orange < green < cyan < red < blue < purple.

3. Arrange the color sequence according to the transparency of the ink. For ink with good transparency, after the two colors are superimposed, the color light of the lower ink layer can pass through the upper ink layer to achieve better subtractive color mixing and display the correct new color. If the yellow ink used is clear yellow, the order of transparency of the four inks is: yellow>magenta>cyan>black. Generally speaking, ink with poor transparency is printed first, and ink with good transparency is printed later.

4. Arrange the color sequence to facilitate overprinting. Due to the objective defects such as paper deformation and expansion, we can arrange the main colors of the printed products with high overprinting requirements to be printed in two adjacent color groups. For example, a two-color machine can be arranged in the same unit to complete the printing at one time to avoid problems such as paper expansion and contraction caused by the existence of paper. For a large area of the field, post-printing can be arranged to avoid problems such as rubbing and smearing during the paper handover process.

In addition, the single-color machine is to overprint the second color after the first color is "dry", while the multi-color machine is a "wet-on-wet" process, so the viscosity of the ink and the amount of ink should be controlled. That is to say, it is very important to arrange the ink with high viscosity to be printed first, and the ink with low viscosity to be printed later, otherwise it will cause the disadvantage of reverse overprinting.

5. Consider process factors such as plate making. When printing, the screen angle of adjacent two color groups differs by at least 30°, which is beneficial to prevent color cast and moiré and other disadvantages.

6. Consider the color order according to the cost. Cheap black and cyan inks are printed first, and expensive magenta and yellow inks are printed later.

Generally, a picture dominated by a large area of landscape (cool tone is the keynote), with black, magenta, cyan, and yellow as the color sequence. Arrange black to be printed first, and black is used to outline the outline, which is convenient for overprinting of other colors. The final print of transparent yellow can be used to adjust the brightness of the entire picture to form glossy and bright colors.

Generally, a picture dominated by characters (warm tone) adopts the sequence of black, cyan, magenta, and yellow. Inks with poor transparency are printed first and will not cover other colors. Magenta and yellow postprints make the faces of the characters ruddy, rich in color and realistic in effect.

Color printing is a craft that combines technology and art. When we arrange the printing color sequence, we can properly consider from the artistic point of view, which can make the printed matter more artistic and meet the needs of readers.