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HC BLUE NO. 20

Description

HC Blue No. 20, also known as N-[6-[(2-Hydroxyethyl)amino]-3-pyridinyl]-2,5-pyridinediamine dihydrochloride, is a semi-permanent hair dye widely used in the cosmetic industry. This synthetic colorant imparts a vibrant blue hue to hair and is particularly effective on pre-lightened or bleached strands. HC Blue No. 20 belongs to the family of hair color molecules that penetrate the hair shaft, providing longer-lasting results compared to temporary dyes.

The compound is water-soluble and has a molecular weight that allows it to penetrate the hair cuticle without causing significant damage. It interacts with the keratin proteins in hair, forming bonds that resist washing and environmental factors. HC Blue No. 20 is often combined with other dye molecules to create a range of blue, purple, and teal shades in hair coloring products.

Safety assessments have shown HC Blue No. 20 to have a low risk of skin irritation when used as directed in hair dye formulations. However, as with all hair dyes, patch testing is recommended to check for individual sensitivities. The ingredient is regulated by cosmetic authorities worldwide, including the European Commission and the FDA, ensuring its safety for use in hair coloring products.