Pigment is insoluble in water and organic solvents, color, black or white powders with high dispersion, played a show the color of the ink. According to the source of the pigment components and chemical composition can be divided into two big categories of organic and inorganic pigments: inorganic pigments are made of non-ferrous metal oxide or metal insoluble metal salts, inorganic pigments can be divided into natural inorganic pigment (mineral pigments) and synthetic inorganic pigments refers to coloured organic compounds of organic pigments, and sources can be divided into two large categories of natural and synthetic. Printing with organic inks are commonly used organic pigments, color range, performance is better than inorganic pigments. High requirements of printing ink pigment, especially color purity of color, dispersion, light resistance, transparency. Usually requiring color ink pigment tones to near spectrum color, saturation is as large as possible, three color inks (cyan, magenta, yellow) pigment transparency must be high, as this will greatly affect print quality.