What is the purpose of a single process color in hair coloring?

The purpose of a single process color in hair coloring is to provide both color deposition and lifting in one application. This method is particularly effective for achieving a lighter shade, as it combines the ability to lighten the natural pigment of the hair while simultaneously depositing the chosen color. This dual action can be advantageous when a client desires a significant change in hue or needs to cover gray hair while also lightening the overall appearance.

In contrast, the other options focus on single aspects of hair coloring. The option that states it only deposits color without any lifting refers to different techniques that do not impact the natural hair color intensity. The option related to color correction implies that the single process is exclusively for fixing previous color issues, while in reality, it has broader applications. The mention of a treatment applied after coloring suggests post-color care rather than the coloring process itself. Overall, the single process color is unique in its ability to transform the hair color in one step through both lifting and depositing tones.