It's not a paint or a dye. The science behind the tan involves a sugar and an amino acid.
How it works is due to the maillard reaction. Its not a paint or a dye but a chemical reaction leading to the change in skin tone. The active ingredient in spray tan is a sugar that reacts with an amino acid in your skin. It is not a paint or a dye, once the tan has developed it will only come off as your skin sloughs or exfoliates off. What you see in the salon immediately is a bronzer indicator, showing where the solution has been sprayed or not sprayed. Bronzer can rub off, a set tan will not sweat or rub off.
DHA is the active ingredient in spray tan solution. It was discovered in 1952 by Eva Wittgenstein. She was doing experiments feeding a dha solution to children with a metabolic disorder, some times children would spit up on her, leaving brown patches only on her skin not her clothes. This was one of the first things week noticed in our studios. Our hot white towels we used under each client to keep their feet warm - did not stain.
The first sunless tanner was "QT" by Coppertone and was introduced in the 1960s.
Starting in the 1980s body builders began using DHA based sunless tanners to enhance their tans from UV beds. This is actually very dangerous as DHA can increase your uv uptake by 100%. When you are spray tanning for vacation we recommend an aerosol spf 30 sunscreen after showering and applying coconut oil. Did you know coconut oil has a natural spf of 4? That is another blog post entirely linked here.
DHA is derived from plant sources such as sugar beets and sugar cane, and by the fermentation of glycerin. Along side the DHA, spray tan solution contains bronzers. These bronzers are almost always natural including black walnut shell and cocoa powder.