What it is
This is a dimethicone (silicone) carrying vinyl groups, which let it crosslink into elastomer networks. On its own it conditions skin and improves slip; it is also a precursor used to build the silicone-gel powders that give sunscreens a smooth, soft-focus feel.
Safety & warnings
Silicones of this type are inert on skin and generally non-irritating and non-comedogenic.
Origin & sourcing
Synthetic silicone fluid.
Questions everyone asks
What is vinyl dimethicone?
It is a silicone used for slip and as a building block for silicone elastomer powders.
Is it greasy?
No, silicones give a light, smooth feel rather than a greasy one.