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HC RED NO. 21

Description

HC Red No. 21, also known as 2-[(4-Aminophenyl)azo]-1,3-dimethyl-1H-imidazolium chloride, is a synthetic hair dye ingredient widely used in the cosmetic industry. This semi-permanent colorant belongs to the azo dye family and is particularly effective in creating vibrant red and burgundy hair shades. HC Red No. 21 is known for its ability to penetrate the hair shaft, providing longer-lasting color results compared to temporary dyes.

The compound exhibits good stability in various hair care formulations and demonstrates resistance to washing and environmental factors. It is often combined with other dye molecules to achieve a broader spectrum of red hues. HC Red No. 21 is compatible with most hair types and can be used in both professional and at-home coloring products.

While generally considered safe for use in hair dyes, some individuals may experience skin sensitization or allergic reactions. As with all hair dyes, a patch test is recommended before application. The ingredient is regulated by cosmetic authorities worldwide, with specific concentration limits set to ensure consumer safety. When used as directed, HC Red No. 21 offers an effective solution for those seeking bold, long-lasting red hair color.