What is the function of a developer in hair coloring?

The function of a developer in hair coloring is to activate the color and open the hair cuticle. This process is essential because the developer contains hydrogen peroxide, which helps to lift the hair’s natural pigment while simultaneously allowing the artificial color to penetrate deeper into the hair shaft. By opening the cuticle, the developer enables the dye to bind effectively, ensuring a more vibrant and long-lasting color result.

In contrast, while adding shine, protecting the scalp, or removing excess pigment are important aspects of the overall coloring process, they do not pertain specifically to the primary role of the developer. Shine can be achieved through various conditioners and finishing products, scalp protection is typically managed by applying barrier creams, and excess pigment removal may involve washing or specific cleansing products. Thus, the developer's primary role is focused on the activation of color and the opening of the hair cuticle, making it a vital component in hair coloring procedures.