What it is
This ingredient is a dimethicone backbone carrying reactive triethoxysilyl groups. The silane groups can hydrolyze and condense to form a durable crosslinked silicone film on skin or to surface-treat powders and pigments. In sunscreens it contributes to a smooth, even film that helps hold the formula and its filters in place and improves overall feel.
Safety & warnings
Silicone and silane-functional siloxanes of this type are generally considered low-irritation and non-sensitizing in cosmetic use. It is not a recognized fragrance allergen.
Origin & sourcing
Synthetic. It is a silicone polymer produced industrially from siloxane and silane chemistry.
Questions everyone asks
What does this silicone do in a sunscreen?
It acts mainly as a film former and surface treatment, helping create a smooth, cohesive layer and improving the feel of the product.
Why does it have triethoxysilyl groups?
Those reactive groups can link together to form a more durable crosslinked film and to bond the silicone to powders and pigments.