What is four-color printing?

Four-color printing is a kind of color printing, which is widely used. Four-color printing generally refers to a printing process that uses yellow, magenta, cyan ink and black ink to copy the color of a color manuscript. What do C, M, Y and K stand for in four-color printing? CMYK printing color mode is a lithographic printing method which uses three primary colors of red, green and blue and black pigment (ink or dye) to realize full-color reproduction according to the principle of subtractive color mixing. CMYK is a color mode that depends on reflection. As long as the images are seen in printed matter, they are all expressed in CMYK mode. Such as periodicals, magazines, newspapers, posters, etc. They are all printed, so they are in CMYK mode. C, short for cyan, which means blue in Chinese; M, short for magenta, Chinese: magenta; Y, short for yellow, Chinese: yellow; K, the last letter of black is taken to avoid confusion with blue. Theoretically speaking, only three kinds of CMY inks are enough, and these three kinds together should turn black. However, due to the current manufacturing process can not produce high-purity ink, the result of CMY addition is actually a dark red. So you need to add special black ink to neutralize it.