One of the most common alcohols used in cosmetics is Ethyl alcohol, also referred to as Ethanol (or simply Alcohol on some cosmetic ingredient listings). It’s the regular old alcohol we are all most familiar with –found in beer and wine, as well as in our hairsprays, gels and facial toners. Yes, really –it’s the exact same thing. But, to remove the tax burden imposed on alcohol intended for ingestion, and also to ensure that people (especially kids) aren’t drinking hairspray, the ethanol used in cosmetic formulations is typically denatured, which creates a bitter taste. Denatured alcohol appears in a cosmetic ingredient listing either as SD Alcohol or Alcohol Denat.
Ethanol is typically derived from sugars, mostly from corn. It is a liquid at room temperature, and has a lot of other cool properties that only chemists would care about. But, one important characteristic you should understand is that it is very “volatile”. Simply put, it evaporates rapidly –much more rapidly than water. Its volatility is one reason why ethanol is used in a lot of hair styling products, such as hairsprays. The fast-drying activity of alcohol allows the fixative to be sprayed onto the surface of hair without “wetting” the hair –which, of course, would ruin the style.
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