Widely used in hair dye formulations as a primary intermediate, it reacts with couplers to produce a range of permanent color shades. Its structure allows for deep penetration into the hair shaft, ensuring long-lasting color. It is especially effective in oxidative hair dyes, where it contributes to both color development and intensity. Due to its stability in alkaline conditions and compatibility with other dye components, it is a preferred choice in many commercial hair coloring products. Also valued for producing natural-looking gray coverage and maintaining hair integrity during the dyeing process.