Propylene Glycol is diol alcohol (it contains two hydroxy groups in 1 and 2 positions—propane-1,2-diol), a humectant or humidifying and delivery ingredient used in cosmetics. It is a water-white, viscous, odorless, hygroscopic liquid with low volatility and is readily soluble in water.
When used in small amounts, propylene glycol prevents products from melting at high heat or freezing when cold. It also helps active ingredients penetrate the skin. Propylene glycol is an antiseptic with similar power to ethanol (very effective in concentrations above 15 – 30 %).
Propylene glycol improves the texture and stability of formulations. It is used in many pharmaceuticals, skincare products, and decorative cosmetics. It also exhibits antioxidant properties. The U.S. Food and Drug Administration has given Propylene Glycol the GRAS (Generally Recognized As Safe) classification.
Propylene glycol is often used as an emulsifier or aid in solubilizing other raw materials, such as parabens, fragrances, and vitamins. It is used in cosmetic formulations such as creams, lotions, foundations, cleansing, and hair care at 1-5% use levels. In some cases, concentration can reach up to 10%, but it is still safe as propylene glycol can be used in cosmetics in concentrations up to 50%.Related ingredients
