Screen printing ink is made up of pigments, linking agents, solvents, and auxiliary agents. Organic solvents and heavy metals have serious damage to the human body. Some solvents in screen printing ink, which volatilized or discharged into the air, pollute the environment and affect the growth of plants and animals. Especially, volatile printing ink is very serious for air pollution. In addition, some solvents and auxiliaries in printing ink are relatively low. When they gather in the air and reach a certain concentration, fire will occur in fire and so on. There are two kinds of pigments in printing ink, that is, inorganic and organic pigments. Their properties are insoluble in water and other media, and have distinct color and stability. Some inorganic pigments contain heavy metals such as lead, chromium, copper and mercury. They all have certain toxicity. They can not be used for printing food packaging and children's toys. Some organic pigments contain some biphenyl rubber, which contains carcinogenic compounds and should be strictly prohibited. Organic solvents can dissolve many natural resins and synthetic resins. It is an important part of various inks. Organic solvents can damage the body and subcutaneous fat. Long term exposure to certain solvents will cause skin dryness and roughness; if skin or penetrate into the blood vessels, with blood will endanger human blood cells and hematopoietic function; solvent gas is sucked into the trachea, bronchus, lung or through blood vessels, lymphatic spread to other organs, and may even lead to muscle body chronic poisoning.