What type of hair color products create a chemical change when mixed with developer?

Oxidative color products create a chemical change when mixed with a developer because they contain a chemical called an oxidizing agent, which typically includes hydrogen peroxide. When combined with the color pigment in the hair color formula, these products undergo a chemical reaction that facilitates the lightening of the natural pigment in the hair and allows for the deposition of new color. This process alters the structure of the hair cuticle and cortex, leading to a permanent change in color.

This differentiation is critical to understand because it distinguishes oxidative hair colors from other types, such as temporary colors or direct dyes, which do not rely on this chemical process. Temporary colors merely coat the outer layer of the hair without penetrating, while direct dyes typically do not require a developer and do not create a chemical change, merely staining the hair. Highlighting color also usually utilizes similar concepts as oxidative colors but is specifically formulated for adding lighter shades rather than a full change in hair color. Understanding the role of developers and the chemical processes involved in oxidative colors helps in choosing the right products for desired hair results.