Application: α-hydroxy acid is a type of organic acid with the hydroxyl group at the α position. Ethyl glycolic acid, lactic acid, mandelic acid and citric acid are common ingredients in cosmetics. α-hydroxy acid can be absorbed quickly, so it has a good moisturizing effect. In addition, it can penetrate into the stratum corneum of the skin, causing keratin shedding and keratin dissolution, and it also has anti-wrinkle and anti-aging effects.