Surfactant - solubilizing

Solubilizing surfactants help to introduce small amounts of fat—soluble substances into the water base, such as perfumes, essential oils, vitamins or plant extracts. Due to this, the composition becomes more homogeneous, does not delaminate or become cloudy too quickly, and the active and aromatic components are distributed more evenly over the product. In the CosIng database of the European Commission, the solubilizing function stands out as a separate cosmetic role of the ingredients, and the surfactants themselves generally help combine water and poorly soluble components in it. (single-market-economy.ec.europa.eu)

For skin and hair, this is important primarily from the point of view of comfort and stability of the formula: the product is easier to apply, feels lighter and more transparent, and fragrant and lipophilic additives do not settle on the surface in drops. Most often, such substances are found in micellar water, tonics, sprays, serums and transparent gels, where you need to "dissolve" the oil in water without a dense creamy texture. Typical examples are Polysorbate 20 and PEG-40 Hydrogenated Castor Oil; polysorbates are widely used as solubilizers and dispersants in cosmetic formulas. (cir-safety.org)

Such ingredients are usually used in small quantities, so their task is not so much to purify as to improve the texture, transparency and technological stability of the product. With a proper formula, they help to make the product more aesthetically pleasing and more convenient to use, without changing its purpose. The safety of many common solubilizers, including polysorbates, was considered separately by CIR experts in the context of use in cosmetics. (cir-safety.org)