Final answer:
Demi-permanent hair color is designed to deposit color without lightening the natural hair pigment, washing out over time and allowing for a more natural look as it does not alter hair structure.
Step-by-step explanation:
The type of hair color formulated to deposit but not lighten color is demi-permanent hair color. Unlike permanent hair color which chemically alters the structure of the hair and can lighten the natural pigment, demi-permanent hair color works by coating the hair shaft and typically washes out over four to six weeks.
This means that it can provide a new color to the hair without removing the underlying natural pigments, which makes it an ideal choice for those looking to enhance their natural color or cover grays without committing to a permanent change.
As with any hair dye, the final shade achieved with demi-permanent color can vary depending on factors like the original hair color and porosity. While it offers a less permanent solution than permanent hair dye, it also allows for a more natural look as root regrowth will be less noticeable, and the color fades over time.