Washington Cosmetology License Practice Exam

Permanent hair color is designed to change the hair's natural pigment and requires a developer to facilitate this process. The developer contains hydrogen peroxide, which activates the color and allows it to penetrate the hair shaft. This chemical reaction not only changes the color but also helps to create long-lasting results that endure until new hair growth occurs.

Using a developer is crucial in this context because it lifts the cuticle layer of the hair, allowing the color molecules to enter and bond effectively with the hair structure. The result is a color that stays vibrant and does not wash out over time, unlike temporary or semi-permanent colors, which do not possess the same chemical makeup or bonding capabilities and thus do not require a developer. Highlighting hair color, though it may utilize a developer as well, primarily focuses on bleaching or lightening strands rather than changing the overall color, making it distinct from the general use of permanent hair color.