To use: Caustic soda is an important basic chemical raw material, originally used to make soap, and then gradually used in light industry, textile, chemical industry and other fields. With the development of aluminum industry and petrochemical industry in the late 1960s, its application scope is more extensive, and the downstream products have reached more than 900 kinds. In light industry, the amount of alkali used in paper industry has been the first in all industries, followed by oil industry and detergent industry. In addition, refrigerant, polytetrafluoroethylene, polyurethane, photosensitive materials are largely used in the production of caustic soda. In the chemical industry, the proportion of caustic soda consumed by organic and inorganic chemicals accounted for 60% and 27% respectively, while the proportion of caustic soda consumed by agricultural insecticides and other substances was 9% and 4% respectively. Caustic soda is widely used in inorganic salts, dyes, coatings, chemical auxiliaries, rubber, petrochemical industry, fine chemical industry, synthetic fibers, plastics, additives, chemical environmental protection and so on. In the textile industry, chemical fiber rinsing and dyeing post-treatment are the biggest users of caustic soda for textile. In other aspects, such as medical resin, silicone resin, electrolytic metal, electroplating, metal heat treatment, mineral treatment and other aspects also consume a lot of caustic soda.