Sodium 4-Amino-1,5-naphthalenedisulfonate is primarily used as an intermediate in the synthesis of dyes and pigments. It plays a crucial role in the production of azo dyes, which are widely applied in the textile industry for coloring fabrics. Additionally, it is utilized in the manufacturing of fluorescent brightening agents, enhancing the whiteness and brightness of paper, detergents, and plastics. In analytical chemistry, this compound serves as a reagent for detecting and quantifying certain metal ions due to its chelating properties. Its water-soluble nature also makes it suitable for applications in aqueous formulations and industrial processes requiring stable sulfonate groups.