What is a key difference between semi-permanent and permanent hair color?

The key difference lies in the longevity and lifting ability of the color. Semi-permanent hair color typically lasts through several washes and is formulated to deposit color without significantly altering the natural hair structure or lifting existing color. This means that it is ideal for enhancing and enriching the natural color rather than changing it dramatically. It does not contain the ammonia or peroxide that would allow it to lift the hair's natural pigment.

On the other hand, permanent hair color contains these chemicals, allowing it not only to deposit a new color but also to lighten or lift the existing color by penetrating the hair shaft. Due to this chemical process, permanent colors offer more options for major changes in hair color but come with the commitment of longer-lasting results. This understanding helps to distinguish the nature and use of different color products, guiding professionals in making the right choices for their clients based on desired outcomes.