What is the primary purpose of using fillers on hair?

Using fillers on hair primarily serves the purpose of equalizing porosity. When hair has uneven porosity, certain areas may absorb color or treatment products differently, leading to a patchy or inconsistent result. Fillers are used to coat the hair, allowing for a more uniform absorption of dye and treatments. This is particularly crucial during color services, as achieving an even application and consistent results is essential for a professional finish.

While conditioning, adding color, and enhancing shine are important aspects of hair care and treatment, they do not specifically address the need for achieving a balanced porosity throughout the hair strands. Conditioners can improve the overall health of the hair, and treatments may enhance shine and color, but fillers uniquely focus on preparing the hair for processes that require uniformity in product adhesion. This makes equalizing porosity a critical function of using fillers for effective hair treatments.