Isodecyl Stearate
AKA “31565-38-5, Octadecanoic acid, isodecyl ester, 2JQ9SQR11V, STEARIC ACID, ISODECYL ESTER, RefChem:791849, DTXSID0067636, ISODECYL STEARATE [INCI], 250-704-9, 8-methylnonyl octadecanoate”
Emollient
Ingredient Facts
Isodecyl stearate
AKA: 31565-38-5, Octadecanoic acid, Isodecyl ester, 2JQ9SQR11V, STEARIC ACID, ISODECYL ESTER, RefChem:791849, DTXSID0067636, ISODECYL STEARATE [INCI], 250-704-9, 8-methylnonyl octadecanoate
Emollient · Emollient · EWG: 4
Plant-Derived
Emollient
Skin Conditioner
Not Clean
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
C28H56O2
Mol. Weight
424.70
CAS #
31565-38-5
Form
Liquid
See origin →
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
Traditional Use
Modern synthetic ester created as a cosmetic emollient and skin-conditioning agent. Developed to provide spreadability and moisture retention in formulations without a traditional or historical use.
Skin Types
●all-skin-types
Best For
Dryness
Pregnancy & Breastfeeding Safe
Yes
Amended Final Report on the Safety Assessment of Hydroxystearic Acid
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Final Report on the Safety Assessment of Isostearic Acid
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Final Report on the Safety Assessment of Oleic Acid, Lauric Acid, Palmitic Acid, Myristic Acid, and Stearic Acid
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Final Report: Safety Assessment of Polyhydroxystearic Acid, Poly(3-Hydroxyoctanoic Acid, and Polylactic Acid as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Re-evaluation: Safety Assessment of Hydroxystearic Acid as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
10-Hydroxystearic Acid
European Commission
EU Cosmetic Ingredient Database (CosIng)
Isodecyl Stearate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Polyhydroxystearic Acid
European Commission
EU Cosmetic Ingredient Database (CosIng)
Stearic Acid
European Commission
EU Cosmetic Ingredient Database (CosIng)
Hydroxystearic Acid
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Isostearic Acid
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Polyhydroxystearic Acid
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Stearic Acid
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Simultaneous contact sensitivity to hydroxystearic acid and C18-36 acid triglyceride in lip glosses.
Kimura M, Kawada A, Ogino M, Murayama Y
Contact dermatitis, 2002
Microemulsions based on TPGS and isostearic acid for imiquimod formulation and skin delivery.
Pescina S, Garrastazu G, Del Favero E, Rondelli V, Cantù L et al.
European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences, 2018
Bio-derived hydroxystearic acid ameliorates skin age spots and conspicuous pores.
Schütz R, Rawlings AV, Wandeler E, Jackson E, Trevisan S et al.
International journal of cosmetic science, 2019
Bio-derived hydroxystearic acid ameliorates skin age spots and conspicuous pores.
Schütz R, Rawlings AV, Wandeler E, Jackson E, Trevisan S et al.
International journal of cosmetic science, 2019
Bio-derived hydroxystearic acid ameliorates skin age spots and conspicuous pores.
Schütz R, Rawlings AV, Wandeler E, Jackson E, Trevisan S et al.
International journal of cosmetic science, 2019
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR