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BASIC YELLOW 40

Description

Basic Yellow 40, also known as 2-[N-ethyl-4-[(4-nitrophenyl)azo]-N-(2-hydroxyethyl)anilino]ethanol, is a synthetic dye primarily used in haircare products. This water-soluble compound belongs to the azo dye family and imparts a vibrant yellow hue to various hair coloring formulations. Basic Yellow 40 is particularly effective in semi-permanent and temporary hair color products due to its ability to adhere to the hair shaft without penetrating deeply into the cortex.

The dye exhibits good color stability and resists fading when exposed to light and washing. It is often combined with other dyes to create a wide range of warm tones, from golden blonde to light brown. Basic Yellow 40 is compatible with most haircare ingredients and can be incorporated into various product forms, including shampoos, conditioners, and styling products.

While generally considered safe for cosmetic use, some individuals may experience skin sensitization or allergic reactions. As with all hair dyes, patch testing is recommended before use. Formulators should be aware of regulatory limits on its concentration in finished products, which may vary by region.