Laureth-23 is a multifunctional ingredient used in cosmetic products for hygiene and care. It may be used as a washing or consistency agent (often it has both functions in one product). It can be found in all kinds of skin care products, including toners, serums and sunscreens. It is also used in hair care products.
Laureth-23 is the INCI name of a non-ionic surfactant with CAS number 68439-50-9. It is a derivative of lauryl alcohol, ethoxylated with 23 moles of ethylene oxide. The amount of ethoxylated groups directly correlates with the viscosity of the product. The higher the amount, the higher the viscosity and it has a direct effect on consistency. Laureth-23 may be used as an alternative to anionic surfactants.
Laureth-23 has been used mainly in the cosmetics industry. In products, it acts as an emulsifier and helps to create stable emulsions, i.e. systems of two immiscible phases: water and oil. This is due to the chemical structure of the Laureth-23 molecule, which creates emulsions by reducing the surface tension between phases and interacting with them. In addition, thanks to the high degree of ethoxylation, Laureth-23 is strongly hydrophilic, i.e. it shows affinity to water molecules. Thus, it perfectly fulfils its functions when creating oil-in-water (O/W) emulsions. Laureth-23 is especially compatible with other emulsifiers of low hydrophilic–lipophilic balance (HLB). Its foaming properties help to produce large amounts of stable foam, e.g. in shampoos. One of the functions of Laureth-23 is solubilisation. The substance enables the incorporation of the ingredients that are not soluble in water or are sparingly soluble in water into an aqueous solution. These ingredients include, among others, essential oils and fragrances. In addition, Laureth-23 has an indirect moisturising effect. The use of products containing this surfactant contributes to the formation of an occlusive layer (thin film) on the surface of the skin and hair. It prevents excessive evaporation of water and has a softening and glossing effect. Laureth-23 is also used in cosmetic products to change their rheological properties, i.e. their viscosity. The correct viscosity level is not only responsible for the consistency and application properties of the product, but also affects its shelf life.
