How does Semi-Permanent Haircolor function?

Semi-permanent haircolor functions primarily by depositing color onto the hair without altering its natural pigment or causing a lightening effect. This type of haircolor utilizes smaller color molecules that can penetrate the cuticle layer of the hair strand to some extent, allowing it to bond with the hair without permanently changing the hair structure.

Unlike permanent haircolor, semi-permanent does not contain ammonia or bleach, which means it does not lift the natural hair color. Instead, it enhances or modifies the existing color and typically lasts for several washes, fading gradually over time. This characteristic makes it ideal for those looking to experiment with color, cover greys, or boost their hair's vibrancy without committing to a long-lasting or drastic change.

The focus on depositing color rather than lightening is what distinguishes semi-permanent haircolor from other types, such as permanent haircolor, which alters the hair structure to ensure a long-lasting effect. Additionally, semi-permanent color does not require a developer, further differentiating its application from that of permanent formulas.