Combination of professional printing and overprinting

1. Monochrome black and four-color black

Usually the black text part of the print must be monochrome black, not four-color black or mixed black.

Monochrome black, refers to K100, C0, M0, Y0

Four-color black refers to K100, C100, M100, and Y100 (if the print register line is self-manufactured, 4-color black should be selected, but it is usually added automatically when the film is output, without manual completion).

Mixed black, refers to K100, CX, MX, YX

2, spot color

A. What is spot color

In general, we use color inks other than C, M, Y, and K for printing. We call them spot colors.

B. Why use spot color printing

(1) For printing less than four colors (also known as overprinting)

For example: The following figure shows the printing process according to the CMYK color scheme. Visually, two red and green colors need CMY3 editions to complete printing.

The following figure shows the spot color printing plate making method. It is directly printed with green and red spot color inks. The entire process uses only two editions, which reduces the number of prints and costs relative to the above CMYK method.

The spot color version can be created using the PANTONE color matching system. In the case where the total number of colors in a work is less than 4 colors, a single color channel of C, M, Y, K can also be used to realize spot colors.

(2) Due to limitations of the CMYK color gamut, spot color printing is generally used for the effect that CMYK cannot stack.

For example: mixed with gold and silver colors.

3, overprint

The following is the graphical effect of the overprint principle.

The PHOTOSHOP Overprint setting uses a "multiple overlay" layer blending mode;

CORELDRAW Overprint Settings Right-click pop-up menu "Overprint Fill" "Overprint Profile";

The ILLUSTRATOR overprint settings are selected in the property tool palette.