Oleyl Betaine
AKA: 871-37-4, 9-Octadecen-1-aminium, N-(carboxymethyl)-N, Inner salt, 2-[Dimethyl(octadec-9-enyl)azaniumyl]acetate
Synthetic
Cleanser
Skin Conditioner
Hair Care
Clean
9-(Z)-Octadecenaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt
Formula
C22H43NO2
Mol. Weight
353.60
CAS #
871-37-4
Form
Liquid
Functions
Antistatic
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Hair Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Foam Boosting
Locks in moisture
Traditional Use
Developed in the late 20th century as a mild synthetic surfactant derived from oleyl alcohol and betaine. Designed to replace harsher surfactants in personal care products while mimicking properties of natural amphoteric compounds.
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
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.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR