Polysilicone-15 Good UV filter Anti-Ageing Polysilicone-15 at a glance Also known as Parsol SLX and dimethicodiethylbenzalmalonate Absorbs the sun’s UVB rays Not approved yet for sunscreen use in the U.S. Authorized in the EU for use in amounts up to 10% Colorless-to-pale yellow viscous liquid Polysilicone-15 description Polysilicone-15, also known as Parsol SLX and dimethicodiethylbenzalmalonate, is a silicone-based UV filter approved for use in the United Kingdom and European Union. Specifically, it absorbs the sun’s UVB rays. Polysilicone-15 has not been approved for use as a sunscreen yet by the United States Food and Drug Administration, which considers sunscreens over-the-counter drugs (in the European Union and UK markets, they are considered cosmetics). In its raw form, polysilicone-15 is a colorless-to-pale yellow viscous liquid. In the EU it is authorized for use in amounts up to 10% in a formula, though typical concentrations in sunscreens only go up to 5%. Since this filter is not broad spectrum, it should always be combined with other filters capable of providing UVA protection. Related ingredients: SPF