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HC YELLOW NO. 4

Description

HC Yellow No. 4 is a semi-permanent hair dye ingredient widely used in the cosmetic industry for its ability to impart vibrant yellow to golden hues to hair. This synthetic colorant belongs to the azo dye family and is particularly effective in coloring lighter hair shades. HC Yellow No. 4 is valued for its stability and longevity compared to temporary dyes, typically lasting through several washes before gradually fading.

In hair coloring formulations, HC Yellow No. 4 is often combined with other dyes to create a spectrum of blonde, golden, and light brown shades. It penetrates the hair shaft, depositing color molecules that adhere to the cortex without significantly altering the hair's structure. This characteristic makes it a preferred choice for gentler coloring processes compared to permanent dyes.

While generally considered safe for use in hair products, some individuals may experience sensitivity or allergic reactions. As with all hair dyes, patch testing is recommended before full application. HC Yellow No. 4 is subject to concentration limits set by regulatory bodies to ensure consumer safety in hair coloring products.