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HC RED NO. 7

Description

HC Red No. 7, also known as 2-[(4-Aminophenyl)azo]-1,3-dimethyl-1H-imidazolium chloride, is a synthetic hair dye compound widely used in the cosmetic industry. This semi-permanent colorant imparts vibrant red hues to hair without the need for oxidative processes. HC Red No. 7 is particularly effective on pre-lightened or naturally light hair, producing shades ranging from bright cherry to deep burgundy.

The compound's molecular structure allows it to penetrate the hair shaft, adhering to the cortex for longer-lasting color. It is often combined with other dyes to create custom shades and enhance color intensity. HC Red No. 7 exhibits good stability in various hair care formulations, including shampoos, conditioners, and styling products.

While generally considered safe for use in hair dyes, some individuals may experience scalp irritation or allergic reactions. Patch testing is recommended before application. The colorant gradually fades with washing, typically lasting 4-6 weeks depending on hair porosity and care routine. To maintain color vibrancy, use of color-safe, sulfate-free shampoos and cool water rinsing is advised. HC Red No. 7 is regulated by cosmetic authorities worldwide, with concentration limits varying by region.