Color printing newspapers and magazines, brochures, cards, posters and similar mass-market items. In this type of industrial or commercial printing, the technique used to print full-color images, such as color photographs, is referred to as four-color-process or merely process printing. Four inks are used: three secondary colors plus black. These ink colors are cyan, magenta, yellow and key (black); abbreviated as CMYK. Cyan can be thought of as minus-red, magenta as minus-green, and yellow as minus-blue. These inks are semi-transparent or translucent. Where two such inks overlap on the paper due to sequential printing impressions, a primary color is perceived. For example,
Shades of magenta a single wavelength. Humans, being trichromats, can only see as far as 380 nanometers into the spectrum, i.e., as far as violet. The hue magenta is the complement of green: magenta pigments absorb green light, thus magenta and green are opposite colors. Before "printer's magenta" was invented in the 1890s for CMYK printing, and "electric magenta" was invented in the 1980s for computer displays, these two artificially engineered colors were preceded by the color displayed at right, which is the color originally called "magenta" made from coal tar dyes in the year 1859. Besides being called original magenta, magenta dye