Used as a key intermediate in the synthesis of high-performance polyesters and liquid crystalline polymers. Its sulfonic acid groups enhance solubility in polar solvents and improve dyeability when incorporated into polymer chains. Commonly applied in the production of sulfonated polyesters for use in dyeable fibers, films, and engineering plastics. Also utilized in specialty polymers requiring thermal stability and chemical resistance. Its rigid naphthalene backbone contributes to increased glass transition temperatures and mechanical strength in the final polymer products.