murphyIsopropyl Isostearate
AKA: 68171-33-5, Nikkol IPIS, Wickenol 131, Isooctadecanoic acid, 1-methylethyl ester, PRISORINE 2021, CRODAMOL IPIS, DERMOL IPIS, JEECHEM IPIS
Synthetic
Emollient
Skin Conditioner
Synthetic
Clean
OriginIsopropyl isostearate is derived from isostearic acid and isopropyl alcohol, both synthetic hydrocarbon compounds. It is synthesized through esterification, where isostearic acid reacts with isopropyl alcohol under catalytic conditions.
The CIR Expert Panel concluded that the alkyl esters, listed subsequently, are safe in the present practices of use and concentration described in this safety assessment when formulated to be non-irritating.
Formula
C21H42O2
Mol. Weight
326.60
CAS #
31478-84-9, 68171-33-5
Form
Liquid
Skin Types
●all-skin-types
Best For
General
Functions
Emollient
Fills in the tiny cracks between skin cells to make everything feel smooth and soft. The "silky finish" ingredient.
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Holds Formula Together
Softens & Smooths
Conditions Skin
Smooths and softens skin
Holds ingredients together
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory0 listings
🛡️Safety-assessed3 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
1
CIR
Insufficient
Pregnancy
—
CIR Safety Findings
Mixed Skin Irritation Results
3 studies / 1 irritating / 1 mixed / 1 not irritating (CIR 111 and 623)
Comedogenic in Testing
Animal test with a comedogenic result in the CIR safety assessment (CIR 111 and 623)
Eye Irritant in Testing
1 study / 1 irritating / reactions slight (CIR 111)
Concentration Guide
Leave-on0.5–19%
Rinse-off0.7–6%
0%50%100%
CIR reported use · 2012 survey
Regulatory Agencies
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR