Here's why:
* Ammonia's role: Ammonia acts as an alkali, which opens up the hair cuticle, allowing the color molecules to penetrate and deposit the color. It also helps the developer (hydrogen peroxide) work more effectively.
* Alternatives: Some brands offer ammonia-free permanent color, but they typically use other alkalis, like monoethanolamine (MEA) or ethanolamine. While these are less harsh than ammonia, they still have the potential to irritate sensitive scalps.
So, while Naturtint is ammonia-free, most other permanent hair colors do contain ammonia. Always read the ingredient list carefully to determine what's in your chosen product. If you have sensitive skin, it's always best to do a patch test before applying any hair color.