Color Printing Design Application Knowledge

In the printing design, the three primary colors of the ink are mixed in different proportions to obtain the desired color spectral tone values. The correct density and balance of the three primary inks printed on the substrate are directly related to the print designer. Although printing design operators can only measure and set the ink density within a limited range, these density ranges can help the printing designer to obtain a wide range of overprint ink colors, regardless of whether the ink is transparent or whether the substrate is pure white. In print design we can find these density ranges in a variety of related publications very conveniently: as described in the FIRST and SWOP standards.

The ink density range in the printing design according to the instructions can be used for any ink overprint sequence, ie YMC, YCM, CMY, CYM, MCY or MYC. But does the printing design produce the same color for each sequence? Actually not.

Even if the density of the field is controlled at absolute value, each overprint sequence in the printing design will produce different overprint colors of red, green, and blue, because the printing ink formulations on each printing design have different properties, such as affecting the coverage rate. Ink opacity. Therefore, the surface energy of the ink-dried film layer printed first (printing design) will affect the wet ink adhesion characteristics of the post-printing (printing design).

The yellow pigments have poor coverage, and the magenta and cyan pigments have good coverage. However, the yellow pigment ink has a high surface energy.

The first step in color management in print design is to determine the best ink overprint sequence and density balance that can provide a high color rendering range.

The GATF association developed a simple color hexagonal color map many years ago to visualize the ratio of different colors. Densitometers can display color differences by measuring hue deviation, grayscale, and overprint colors and compare them with the three primary colors.

For example, in the three corners of the hexagonal color diagram, the ideal three-primary ink (YMC) is on the three corners, and the overprinted composite color (RGB) is on the other three corners. The center of the hexagon is the neutral color (white to gray). To black). The greater the color strength of the ink, the closer it is to the corners and the farther away from the neutral color.