Introduction:
Formaldehyde is used in various organic synthesis and reactions. It is used in the textile industry in the area of crosslinking molecules to vary the properties of fabrics. In the food industry it is used to reinforce and improve packaging of meats and produce. It can help improve the water resistance of biodegradable collagen films.

Application:
Formaldehyde is an important organic raw material, which is mainly used in plastic industry (such as phenolic resin, urea-formaldehyde plastics -- electroalumina), synthetic fiber (such as vinylon -- polyvinyl formal), leather industry, medicine, dye and so on. Formalin has bactericidal and antiseptic ability, can leach biological specimen, its dilute solution (0.1-0.5%) can be used in agriculture to soak seeds, disinfect seeds. In industry, methanol is often used to produce formaldehyde by catalytic oxidation. Formaldehyde can react with silver mirror in silver ammonia solution, so that a thin layer of bright silver is attached to the inner wall of the test tube (combined silver is reduced, and formaldehyde is oxidized). Red precipitated cuprous oxide was produced by reaction with newly prepared copper hydroxide suspension.