Which type of hair is presoftening commonly used on?

Presoftening is a technique primarily utilized to enhance the color penetration in resistant and/or gray hair. This type of hair often has a tighter cuticle layer, which can impede the absorption of hair color. Gray hair, in particular, tends to have a different structure and may not absorb color as easily as pigmented hair.

The presoftening process involves using a mild alkaline solution to open the cuticle layer, which allows for better color absorption. This ensures that the color develops evenly and effectively. By opening the cuticle slightly, it also prepares the hair to accept the hair dye more thoroughly, leading to a more vibrant and long-lasting result.

In contrast, the other hair types mentioned either do not require the same level of treatment to achieve color results or may react differently to such a process.