Vinyl Dimethicone/Methicone Silsesquioxane Crosspolymer

This is an inert, high–molecular weight silicone elastomer/resin crosspolymer used mainly for texture, slip, and blurring at low-to-moderate levels (often a few percent) and it is not biologically active. Clinical experience and patch-testing data for similar non-volatile silicone crosspolymers show very low rates of irritation/sensitization because they are non-reactive and largely remain on the skin surface. Rare issues are usually mechanical/occlusive intolerance in acne- or dermatitis-prone patients rather than true chemical irritation, so it scores as exceptionally gentle but not absolutely inert. Safety Notes: In commercial leave-on cosmetics (primers, siliconey moisturizers, foundations, blurring sunscreens), this silicone elastomer crosspolymer is often used at low levels (~0.1–1%) for slip/soft-focus and texture refinement, especially when paired with other silicones. Higher-strength consumer products such as “pore-filling” primers, matte blurring balms, and elastomer-gel textures can reach ~10–20% active elastomer to build a cushiony, velvety film and oil-absorption/blur; rinse-off products typically sit at the low end due to cost and rinse-away performance.