Sodium Acrylates Copolymer

Sodium Acrylates Copolymer is a high–molecular weight synthetic film-former/thickener used at low concentrations (typically well under a few percent) and is generally not skin-penetrating, with patch-test data and broad cosmetic use suggesting very low irritancy. In most formulas it functions as an inert texture/viscosity agent rather than a reactive active, so clinically significant irritation is uncommon. Rare stinging or dermatitis can still occur in highly compromised barriers or from the overall formula matrix, so I score it as exceptionally gentle rather than completely inert. Safety Notes: In commercial skincare, sodium acrylates copolymer is commonly used as a rheology modifier/film former at very low levels (~0.05–0.3%) in lotions, serums, and sunscreens (leave-on) to build viscosity, stabilize emulsions, and improve slip. Higher levels (1–5%) are seen in thicker gel-creams, peel-off/film-forming masks, and some makeup-skincare hybrids to create structure and a continuous film; the upper end (~8–10%) occurs in consumer-available high-hold styling/film gels or specialized mask/primer-type products where the polymer is the primary structurant rather than a minor stabilizer. Rinse-off cleansers typically sit toward the low-to-mid end because excessive levels can feel tacky and can be harder to rinse clean.