Used primarily as a developing agent in color photography, it plays a crucial role in the formation of dye images by reacting with oxidized developers to produce color couplers. In the textile industry, it is employed for dyeing and printing processes, particularly in the synthesis of azo dyes, which are known for their vibrant and durable colors. Additionally, it finds application in analytical chemistry as a reagent for detecting and quantifying various substances due to its ability to form colored complexes. Its use in research and development is also notable, where it serves as an intermediate in the synthesis of more complex organic compounds.