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4-NITRO-O-PHENYLENEDIAMINE DIHYDROCHLORIDE

Description

4-Nitro-o-phenylenediamine dihydrochloride is a potent hair dye ingredient known for its ability to impart deep, rich color to hair fibers. This synthetic compound belongs to the family of aromatic diamines and is primarily used in oxidative hair coloring formulations. Its molecular structure allows for efficient penetration into the hair shaft, where it reacts with hydrogen peroxide to form larger, color-producing molecules.

In hair dye formulations, 4-nitro-o-phenylenediamine dihydrochloride is often combined with other dye precursors to achieve a wide range of color shades, particularly in the brown to black spectrum. It is valued for its color intensity and longevity, providing lasting results that resist fading. However, due to its potential for skin sensitization and allergic reactions, patch testing is strongly recommended before use.

While effective as a coloring agent, this compound is subject to regulatory restrictions in many countries due to concerns about its safety profile. Formulators must adhere to maximum concentration limits set by regulatory bodies and ensure proper labeling of products containing this ingredient. Alternative, less sensitizing dye precursors are increasingly being sought in the haircare industry to address these concerns.