Used primarily as a key intermediate in the production of dyes and pigments, particularly for hair dyes and textile coloring. It plays a crucial role in creating oxidative hair dyes, where it reacts with other compounds to form long-lasting color. Additionally, it is employed in the synthesis of certain polymers and as a reagent in analytical chemistry for detecting trace amounts of substances, such as chlorine in water, or as an indicator in oxidation-reduction reactions. Its applications also extend to the development of photographic chemicals, the plastics and rubber industries to enhance material durability, and as a component in some industrial processes requiring precise chemical reactions.