1. It is used to produce sulfur dyes in the dye industry and it is the raw material for sulfur blue and sulfur blue. The printing and dyeing industry is used as a dye assistant to dissolve sulfur dyes.
2. Adding an appropriate amount of sodium sulfide to the alkaline etching solution of aluminum and alloy can significantly improve the quality of the etching surface, and it can also be used to remove alkali-soluble heavy metal impurities such as zinc in the alkaline etching solution.
3. Sodium sulfide can also be used for the treatment of conductive layer in direct electroplating.
4. Used as a corrosion inhibitor. It is also a raw material for sodium thiosulfate, sodium polysulfide, sulfur dyes, etc.
5. Used in the manufacture of sulfur dyes, leather depilatory, metal smelting, photography, rayon denitration, etc.