Dark brown oily liquid. After refining, it is a clear light yellow or orange liquid with a specific odor. Almost insoluble in water, but soluble in petroleum ether, ethanol, benzene and hydrocarbons. Corrosive to some metals, especially lead and zinc. It is used to make naphthenic acid metal salt, as catalyst, paint drier and wood preservative. This product is mainly used to prepare naphthanates, its sodium salt is a cheap emulsifier, agricultural promoter, stain remover in textile industry; lead, manganese, cobalt, iron, calcium and other salts are drying agents for printing inks and coatings; copper salt, mercury salt is used as wood preservative and pesticide, bactericide; aluminum salt is used for grease and solidification gasoline and flare. Its nickel, cobalt and molybdenum salts can be used as organic synthesis catalysts and drying agents, and some salts can also be used as additives for special oils. The high-carbon aliphatic esters of naphthenic acid are suitable for precision mechanical oils, used in telephones, clocks, meters, etc. It can also be used to prepare synthetic detergents, insecticides, rubber accelerators, and solvents.