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HC YELLOW NO. 6

Description

HC Yellow No. 6, also known as Basic Yellow 57, is a synthetic hair dye molecule widely used in semi-permanent and temporary hair coloring products. This water-soluble compound belongs to the family of azo dyes and is characterized by its ability to impart vibrant yellow to golden hues to hair without requiring oxidative processes.

The molecule's structure allows it to penetrate the hair shaft partially, adhering to the cuticle and cortex layers. This results in a color that gradually fades over multiple washes, typically lasting 4-6 weeks. HC Yellow No. 6 is often combined with other dye molecules to create a spectrum of warm tones, including brassy blondes and light brown shades.

In formulations, HC Yellow No. 6 is typically used at concentrations between 0.1% to 1.5%, depending on the desired intensity and shade. It performs optimally in slightly acidic to neutral pH environments, which helps to minimize potential scalp irritation. While generally considered safe for use in hair dyes, some individuals may experience allergic reactions. As with all hair dyes, a patch test is recommended before full application to assess individual sensitivity.