Used as an intermediate in the synthesis of dyes and pigments, particularly in the production of naphthalene-based sulfonate derivatives. It plays a key role in creating water-soluble colorants for textiles, paper, and leather due to its ability to form stable sulfonamide linkages. Also utilized in the development of photoactive compounds for imaging applications and in some cases as a precursor for fluorescent whiteners in detergents. Its reactive chlorosulfonyl group enables easy functionalization for custom organic synthesis in research and industrial settings.