What is an effect of ammonia in hair coloring?

Ammonia plays a crucial role in the hair coloring process by helping to swell the cuticle of the hair. The cuticle is the outermost layer of the hair shaft, and its primary function is to protect the inner layers. When ammonia is present in hair color products, it elevates the pH of the hair, causing the cuticle to lift or swell. This process allows the hair color molecules to penetrate more effectively into the hair shaft, resulting in a more uniform and lasting color result.

This swelling action is essential for the effective application of permanent hair color, as it prepares the hair to receive and hold the dye. A proper understanding of how ammonia interacts with the hair structure is vital for colorists to achieve optimal coloring outcomes while minimizing damage to the hair.