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HC BLUE NO. 4

Description

HC Blue No. 4 is a semi-permanent hair dye that imparts a vibrant blue hue to the hair. This synthetic colorant belongs to the family of HC (Hair Color) dyes, which are designed to penetrate the hair shaft without the need for oxidative developers. HC Blue No. 4 is particularly effective on pre-lightened or naturally light hair, providing intense color results that gradually fade over time.

The compound is water-soluble and has a relatively low molecular weight, allowing it to diffuse into the hair cortex. Its chemical structure enables it to form weak bonds with hair proteins, resulting in a color that typically lasts through several washes. HC Blue No. 4 is often used in combination with other HC dyes to create a variety of blue-based shades and tones.

While generally considered safer than permanent oxidative dyes, HC Blue No. 4 may still cause allergic reactions in some individuals. It is important to perform a patch test before use. The dye's longevity and vibrancy can be enhanced by using color-safe shampoos and conditioners, as well as minimizing exposure to heat styling and UV radiation.