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HC BLUE NO. 5

Description

HC Blue No. 5, also known as Acid Blue 7, is a semi-permanent hair dye molecule widely used in the cosmetic industry for its vibrant blue coloration. This synthetic colorant belongs to the triarylmethane family of dyes and is particularly effective in creating cool-toned hair shades. HC Blue No. 5 is appreciated for its ability to adhere to the hair shaft without penetrating deeply into the cortex, allowing for longer-lasting color results compared to temporary dyes.

The molecule's structure enables it to form ionic bonds with hair proteins, enhancing its staying power through multiple washes. It is often combined with other dye molecules to create a spectrum of blue, purple, and green hair colors. HC Blue No. 5 performs optimally in slightly acidic environments, which helps to seal the hair cuticle and lock in the color. This dye is generally considered safe for use in hair products when formulated and applied according to regulatory guidelines. However, as with all hair dyes, patch testing is recommended to check for potential allergic reactions. HC Blue No. 5 is not approved for use around the eye area or in products that may come into contact with mucous membranes.