Hydrotrope

Hydrotropes are auxiliary components that help substances that are poorly soluble in water to be distributed more evenly in the formula. In cosmetics, they are needed primarily for the stability and transparency of the composition: they reduce the risk of turbidity, delamination and precipitation, help to combine the aqueous phase with perfumes, acids, surfactants and other components. Therefore, such substances are especially common in shampoos, shower gels, cleansers and liquid lotions, where a homogeneous texture, convenient dosing and a pleasant appearance of the product are important. The definition of this function corresponds to the CosIng database, where hydrotrope refers to substances that increase the solubility of other ingredients in water. (single-market-economy.ec.europa.eu)

For skin and hair, such ingredients usually work not as active care, but as technological assistants. They do not moisturize or regenerate by themselves, but they make the formula more stable and thus help the cleansing and caring components to be distributed predictably. As a result, the product foams easier, washes off better and retains its claimed properties during the shelf life. Typical examples are sodium—Sodium xylenesulfonate and Ammonium Xylenesulfonate: both are used as hydrotropes in cosmetic formulas, especially in cleansing products. Safety assessments of Cosmetic Ingredient Review have been published for a number of such compounds when used in cosmetics in existing concentrations and usage formats. (incidecoder.com)