Back to Ingredient Dictionary

BASIC BLUE 41

Description

Basic Blue 41, also known as 2-[(4-ethoxyphenyl)amino]-1H-benzo[de]isoquinoline-1,3(2H)-dione, is a synthetic dye utilized in various haircare formulations. This water-soluble compound exhibits a vibrant blue hue and is primarily employed as a colorant in temporary hair dyes and toning products.

The ingredient functions by adhering to the hair shaft, providing a temporary color enhancement or tonal correction. It is particularly effective in neutralizing unwanted yellow or brassy tones in blonde, gray, or lightened hair. Basic Blue 41 is often incorporated into shampoos, conditioners, and leave-in treatments designed for cool-toned hair maintenance.

While generally considered safe for cosmetic use, it's important to note that Basic Blue 41 may cause skin or scalp irritation in sensitive individuals. As with all hair dyes, patch testing is recommended prior to full application. The ingredient's color intensity can vary depending on the hair's porosity and the product's formulation.

Basic Blue 41 is typically used in concentrations of 0.1% to 1% in haircare products. Its efficacy may diminish with repeated washing, making it suitable for temporary color transformations or between-salon maintenance of cool hair tones.