What is spot color printing?
Spot color is different from C, M, Y, K, which means that it is not a color synthesized by printing C, M, Y, and K during printing, but is pre-mixed or ink specially used in book printing factory. A specific ink produced by the factory to print that color. For each spot color of printed matter, there is a special color version corresponding to it inprinting.
Use spot colors to make colors more accurate. Although the color cannot be accurately represented on the computer, through the pre-printed color swatches of the standard color matching system, you can see the accurate color of the color on the paper, such as the PANTONE color matching system, which creates a very detailed color swatch card .
Ink printing color, there are generally two ways:
(1) Printing colors using four-color inks
(2) Mix the printed inks to prepare spot colors, that is, use spot color printing to express colors with solid colors or dots. The color assignment and plate making methods of these two methods are different in the printing design.
In packaging printing, spot color printing is often used to print large-area background colors. The covers of packaging products or book printing are often composed of uniform color blocks of different colors or regular gradient color blocks and text. These color blocks and text can be overprinted with four primary color inks after color separation, or can be mixed with spot color ink. , and then print only a certain spot color ink at the same color block.
In the case of comprehensively considering improving the printing quality and saving the number of overprints, sometimes it is necessary to use spot color printing. The ink prepared by spot color printing is obtained according to the principle of color material subtractive color mixing, and its color brightness is low and saturation is high. Compared with four-color printing, it is easier to obtain a uniform and thick printing effect of ink color.
The color block printed by the four-color printing process is mostly composed of a certain proportion of dots. When printing the dots, the change of the thickness of the ink layer and the change of the printing process conditions can cause the color intensity and dots. A change in the degree of enlargement, which results in a change in color. Therefore, it is not easy to obtain the effect of uniform ink color when the color blocks are overprinted by the four-color printing process.
The cost of spot color should be considered from the point of view of economic benefits, mainly to see whether the use of spot color printing process can save the number of overprints. Because reducing the number of overprints can save both printing costs and pre-press production costs. Generally, spot color printing is usually used for printing with three colors or less. If more than four colors are required for printing, CMYK four-color printing is appropriate in terms of cost. Therefore, you should decide which method to use to achieve cheap book printing service before starting printing.
In addition, if there are already four printing colors on the same layout, it is equivalent to one more color for printing. If the printing machine has no extra printing units (such as a printing machine with less than four colors or a four-color printing machine), it will be used again. It takes twice as long to print and the cost is higher.