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HC RED NO. 19

Description

HC Red No. 19, also known as 1-Amino-2-nitro-4-(2-hydroxyethyl)aminobenzene, is a synthetic hair dye compound primarily used in semi-permanent and temporary hair coloring products. This water-soluble ingredient imparts a vibrant red hue to hair and is often combined with other dyes to achieve various shades and tones.

The molecule consists of a benzene ring with amino, nitro, and hydroxyethyl groups attached, contributing to its color-producing properties. HC Red No. 19 penetrates the hair shaft, depositing color molecules that adhere to the hair's cortex without significantly altering its structure. This characteristic allows for a gradual fade-out over multiple washes, typically lasting 4-6 weeks.

In formulations, HC Red No. 19 is generally used at concentrations ranging from 0.5% to 2%, depending on the desired intensity and shade. It performs optimally in slightly alkaline environments (pH 7-9) and is often paired with developers or oxidizing agents to enhance color longevity.

While generally considered safe for use in hair dyes, some individuals may experience skin sensitization or allergic reactions. Patch testing is recommended before use, especially for those with sensitive skin or a history of hair dye reactions.