What type of coloring system results in gradual color development with each use?

The type of coloring system that results in gradual color development with each use is a progressive coloring system. This method typically contains metallic salts that build up in the hair over time. With each application, these metallic compounds deposit more color onto the strands, gradually darkening and enhancing the overall hue of the hair. This means that clients can achieve a more intense color with repeated use, as the deposited color layers accumulate.

In contrast, semi-permanent dyes offer temporary color that lasts through several shampoos but does not progressively darken with each use; they are more about adding or enhancing color without long-term commitment. Permanent dyes create a lasting change by lifting the natural color and depositing artificial color, requiring a more extensive chemical process and commitment to upkeep. Temporary dyes are designed to wash out quickly and do not build up; they are often used for immediate, short-term color effects. Understanding these differences is crucial for selecting the appropriate type of coloring method based on desired results and client preferences.