Butylene/Ethylene/Styrene Copolymer is a synthetic polymer used in cosmetics primarily as a film-forming agent and to modify texture and viscosity. It helps create smooth, cohesive films and can stabilize formulations, particularly in stick or balm-type products.
| Reported effect | How often | Notes |
|---|---|---|
| Skin irritation | Rare | Polymeric film formers are generally inert; mild irritation is uncommon and usually linked to other formulation components. |
| Contact allergy/sensitization | Very rare | Large copolymers have low sensitizing potential due to limited skin penetration. |
| Follicular occlusion/comedogenicity | Rare | Film-forming polymers may theoretically contribute to occlusion in acne-prone individuals, though data are limited. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.