Which chemical is used to lift hair color?

Hydrogen peroxide is the chemical specifically used to lift hair color during the hair coloring process. It acts as an oxidizing agent in perm color processes and is essential for the lightening of natural pigments in the hair. When combined with hair dye, hydrogen peroxide develops the color and allows it to penetrate the hair shaft. This is critical for achieving the desired shade, especially when moving to a lighter color.

Ammonia also plays a role in the hair coloring process, but its primary function is to open up the hair cuticle, allowing other chemicals to penetrate. While it is vital in the coloring process, it does not lift the color itself. Sodium bicarbonate and alcohol do not serve this specific purpose in hair color lifting. Sodium bicarbonate is more commonly used as a gentle exfoliating agent or pH adjuster, and alcohol can be found in various hair products but is not effective for lifting color.