Red Seal Hairstylist Practice Exam

Permanent hair color is classified as oxidative hair color because it contains ammonia and requires a developer, which is typically hydrogen peroxide. The developer is essential in the color process because it opens the hair's cuticle, allowing the color to penetrate the hair shaft.

When oxidative agents are mixed with the hair color, they cause a chemical reaction that enables the dye molecules to become larger, allowing for a more lasting deposit of color. This process not only changes the color of the hair but also can lighten the natural pigment within the hair.

Other types of hair color, such as temporary and semi-permanent hair colors, do not penetrate the hair shaft in the same way and do not require a developer. Temporary hair colors typically coat the outer layer of the hair and can be washed out easily, while semi-permanent hair colors generally last longer than temporary options but still lack the permanent aspect that oxidative colors provide.