Couleur quadrichromique (quadrichromie)

Process color printing, also called four-color printing, works by layering halftone patterns of the four CMYK inks at specific angles to create the illusion of continuous tone. Each ink is applied through a separate plate, and the overlapping dots fool the eye into perceiving a wide range of colors. Process color is the standard for printing photographs, magazines, and any material requiring a large number of different colors. Its main limitation is gamut size; certain vivid oranges, greens, and purples are impossible to reproduce accurately with CMYK inks alone, requiring spot color supplementation for exactness.