Eco Device Enterprise ~ Toner Cartridge Remanufacturer Malaysia

From Wikipedia ~ In the printing industry, to produce the varying colors the subtractive primaries cyan, magenta, and yellow are applied together in varying amounts. Before the colour names cyan and magenta were in common use, these primaries were often known as blue-green and purple, or in some circles as blue and red, respectively, and their exact color has changed over time with access to new pigments and technologies.

Mixing yellow and cyan produces green colors; mixing yellow with magenta produces reds, and mixing magenta with cyan produces blues. In theory, mixing equal amounts of all three pigments should produce grey, resulting in black when all three are applied in sufficient density, but in practice they tend to produce muddy brown colors. For this reason, and to save ink and decrease drying times, a fourth pigment, black is often used in addition to cyan, magenta, and yellow.