Stearoxytrimethylsilane

AKA: Trimethyl(octadecyloxy)silane, 18748-98-6, Stearoxy trimethylsilane, Stearyloxytrimethylsilane, Stearoxy trimethyl silane, SILCARE SILICONE 1M71
Plant-Derived
Emollient
Skin Conditioner
Clean
OriginDerived from silicone compounds, specifically trimethylsilanol and stearyl alcohol as starting materials. Synthesized through condensation reaction between stearyl alcohol and trimethylsilane under catalytic conditions.
Trimethyl(octadecyloxy)silane
Formula
C21H46OSi
Mol. Weight
342.70
CAS #
18748-98-6
Form
Liquid
Skin Types
●all-skin-types
Best For
Dryness
Pregnancy & Breastfeeding Safe
Yes
Functions
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Emollient
Fills in the tiny cracks between skin cells to make everything feel smooth and soft. The "silky finish" ingredient.
Locks In Moisture
The paper trail
🔬Peer-reviewednone on file
⚖️Regulatory1 listing →
🛡️Safety-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
1
CIR
Safe as used
Pregnancy
Yes
Concentration Guide
Leave-on0.1–0.55%
Rinse-off0.55%
0%50%100%
CIR reported use · 2015 survey
Regulatory Status
USA✔ permitted
EU⚠ restricted
JAPAN⚠ restricted
CANADA⚠ restricted
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR