Stearic Acid
AKA “Octadecanoic acid, 57-11-4, n-Octadecanoic acid, Stearophanic acid, Stearex Beads, Cetylacetic acid, 1-Heptadecanecarboxylic acid, Pearl stearic, Industrene R”
Acid
Ingredient Facts
Stearic acid
AKA: Octadecanoic acid, 57-11-4, N-Octadecanoic acid, Stearophanic acid, Stearex Beads, Cetylacetic acid, 1-Heptadecanecarboxylic acid, Pearl stearic, Industrene R
Acid · Cleansing · EWG: 1
Plant-Derived
Cleanser
Emulsifier
Plant Oil
Acid
Clean
Octadecanoic acid is a C18 straight-chain saturated fatty acid component of many animal and vegetable lipids. As well as in the diet, it is used in hardening soaps, softening plastics and in making cosmetics, candles and plastics. It has a role as a plant metabolite, a human metabolite, a Daphnia magna metabolite and an algal metabolite. It is a long-chain fatty acid, a saturated fatty acid and a straight-chain saturated fatty acid. It is a conjugate acid of an octadecanoate. It derives from a hydride of an octadecane.
Solubility 1 to 10 mg/mL at 73 °F (NTP, 1992)
Formula
C18H36O2
Mol. Weight
284.50
CAS #
57-11-4
Form
Liquid
See origin →
Functions
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Emulsion Stabilising
Forces oil and water to stay mixed instead of separating into layers. The unsung hero holding your lotion together.
Refatting
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Emulsifying
Forces oil and water to stay mixed instead of separating into layers. The unsung hero holding your lotion together.
Surfactant Emulsifying
Skin Types
●all-skin-types, gentle
Take the Skin ID quiz to see if this matches your skinAmended 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)
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