The library

Ingredient library

Every ingredient SkinAtlas knows about — all 2402 of them. What each one does, what it works well with, and what to watch for.

All 2402 ingredients — page 91 of 101

Emollient
Squalane

A stable, lightweight emollient that mimics skin's own lipids.

EMOLLIENTHAIR CONDITIONINGREFATTINGSKIN CONDITIONING
Softens skinNon-greasyWell tolerated
+ Retinol
Emollient
Squalene

The unsaturated C30 triterpene precursor to squalane, present in human sebum and plant oils such as olive oil; highly susceptible to peroxidation, which distinguishes it from its stable, fully saturated counterpart squalane.

emollientskin conditioningskin replenishing
Natural component of human sebum (~10–15%) — highly skin-compatibleEmollient that softens and smooths skinSupports the skin's surface lipid film
Prone to oxidation on exposure to air and UV, forming squalene peroxides — comedogenic and pro-inflammatory byproductsOxidised form (squalene monohydroperoxide) is more comedogenic than established comedogenic cosmetic ingredients in controlled studies
+ Tocopherol
Other
Stearalkonium Hectorite

A quaternary ammonium salt of hectorite clay used as a thickener and rheology modifier in anhydrous and low-water cosmetic formulations.

thickenerviscosity-increasingrheology-modifier
Stabilizes anhydrous formulations such as foundations and colour cosmeticsImproves spreadability and texture
Surfactant
Steareth-10

A PEG-10 ether of stearyl alcohol used as an emulsifier and surfactant in creams and lotions.

emulsifiersurfactant
Stabilizes oil-in-water emulsionsImproves texture and spreadability of creams and lotions
May contain trace 1,4-dioxane as a manufacturing by-product of ethoxylation; purification steps can reduce levels (FDA recommends ≤10,000 ppb in cosmetics)
Surfactant
Steareth-20

A PEG-20 ether of stearyl alcohol used as an emulsifier in a wide range of cosmetic emulsions.

emulsifiersurfactant
Stabilizes oil-in-water emulsionsImproves product texture and skin feel
May contain trace 1,4-dioxane as a manufacturing by-product of ethoxylation; purification steps can reduce levels (FDA recommends ≤10,000 ppb in cosmetics)
Surfactant
Steareth-21

A PEG-21 ether of stearyl alcohol functioning as an emulsifier in cosmetic creams and lotions.

emulsifiersurfactant
Stabilizes oil-in-water emulsions with slightly higher HLB than Steareth-20Improves consistency and skin feel of emulsions
May contain trace 1,4-dioxane as a manufacturing by-product of ethoxylation; purification steps can reduce levels (FDA recommends ≤10,000 ppb in cosmetics)
Emollient
Stearic Acid

A saturated C18 fatty acid used as an emollient, emulsifier and thickener that gives creams a rich texture.

emollientemulsifierthickener
Softens and conditions skinStabilizes emulsionsAdds body to creams
Other
Stearoxyhydroxypropyl Methylcellulose
STEAROXYHYDROXYPROPYL METHYLCELLULOSE

A stearoyl ether of hydroxypropyl methylcellulose. A cellulose-derived thickener that also functions as an emulsion stabilizer. Used in Elixir Reflet SPF50+ sunscreen for texture and stability.

viscosity-increasingfilm-formeremulsion-stabilizer
Thickens and stabilizes emulsionsImproves sunscreen texture
+ Carbomer+ Xanthan Gum
Surfactant
Stearoyl Glutamic Acid

A fatty acid-amino acid conjugate (stearic acid + glutamic acid) used as a mild emulsifier and skin-conditioning agent, particularly common in Japanese sunscreen formulations.

emulsifierskin-conditioning
Acts as an amino acid-derived emulsifier with good skin compatibilityProvides a smooth, non-greasy skin feel
Emollient
Stearoyl Inulin

An ester of stearic acid and inulin (a plant polysaccharide from chicory) used as a natural, plant-derived emollient and film-former.

emollientfilm-formeremulsifier
Provides a smooth, non-greasy emollient skin feelActs as a plant-derived alternative to silicones for film formationSupports skin barrier by forming a protective layer
Surfactant
Steartrimonium Bromide

A quaternary ammonium compound used as an antistatic agent and mild surfactant, also providing some antimicrobial activity.

antistaticsurfactantpreservative-booster
Provides antistatic conditioning to skin surfaceMild antimicrobial supporting preservation
Quaternary ammonium compound; may be irritating at high concentrations
Other
Steartrimonium Chloride
STEARTRIMONIUM CHLORIDE

A quaternary ammonium salt (quat) derived from stearyl alcohol. Used as a conditioning agent and emulsifier. In Rosette's gommage gel, it helps create the physical exfoliation effect as the product is rubbed on skin.

conditioningemulsifier
Conditioning agent — reduces frictionEmulsifying in W/O systems
Cationic surfactant — may not be compatible with anionic surfactants
+ Carbomer+ Glycerin
Emollient
Stearyl Alcohol

A long-chain (C18) fatty alcohol that softens skin, stabilizes emulsions, and adds body to creams; not drying like volatile alcohols.

emollientemulsifierthickener
Softens and conditions skinStabilizes and thickens creams and lotions
Emollient
Stearyl Behenate

The ester of stearyl alcohol (C18) and behenic acid (C22), producing a waxy solid at room temperature. Functions primarily as a rich emollient and emulsion stabilizer in cream formulations. The long C22 chain of behenic acid contributes to the characteristic dense, smooth texture without the tackiness of shorter-chain emollients.

emollientviscosity-controllingskin-conditioning
Wax ester that imparts a rich, smooth texture to creams without a greasy or occlusive feelHelps stabilize emulsion systems by raising viscosity and contributing structure to the oil phaseLong-chain fatty acid ester compatible with barrier lipids — integrates well into cream-to-serum and sleeping-mask formats
+ Cetearyl Alcohol+ Shea Butter+ Ceramide NP
Emollient
Stearyl Dimethicone
STEARYL DIMETHICONE

A dimethicone functionalized with stearyl (C18) groups. Provides conditioning and emollient properties with a smooth, dry feel. Used in Ishizawa's urea face cream.

emollientskin-conditioning
Conditions and softens skinSmooth, non-greasy feel
+ Dimethicone+ Glycerin
Soothing
Stearyl Glycyrrhetinate

The stearyl ester of glycyrrhetinic acid (from licorice root), used in cosmetics as a skin-soothing and conditioning agent with anti-inflammatory properties.

soothingskin-conditioning
Soothes redness and irritation via anti-inflammatory glycyrrhetinic acidConditions and softens skinForms a protective film that improves skin smoothness
Soothing
Stearylglycyrrhetinate

The stearyl ester of glycyrrhetinic acid — a lipid-soluble licorice derivative used in Korean hanbang and sensitive-skin formulas for its potent, well-tolerated anti-inflammatory activity.

soothinganti-inflammatoryskin-conditioning
Lipophilic ester of glycyrrhetinic acid (licorice root active) with enhanced skin penetrationAnti-inflammatory action reduces redness and helps soothe reactive skinMore stable and oil-compatible than water-soluble licorice derivatives
+ Centella Asiatica Extract+ Dipotassium Glycyrrhizate
Soothing
Stellaria Media Extract

An extract from Stellaria media (chickweed), a common herb with a long tradition of use in folk medicine for soothing and relieving itchy, inflamed skin conditions.

soothinganti-inflammatoryskin-conditioning
Traditionally used to soothe dry, itchy, and irritated skinAnti-inflammatory properties help calm redness and inflammationProvides mild moisturizing and skin-conditioning effects
Generally considered safe; rare contact allergy possible
Other
Stevioside

A sweet-tasting diterpene glycoside isolated from Stevia rebaudiana (stevia). Best known as a natural sweetener, stevioside is used in cosmetics at trace levels as a conditioning and antioxidant functional agent. Some research suggests mild anti-glycation activity (inhibiting the Maillard reaction that degrades skin proteins). Appears in lip treatments where its sweetness perception may be intentional.

skin-conditioningantioxidant
Diterpene glycoside from Stevia rebaudiana with mild antioxidant and skin-conditioning propertiesStudied for potential anti-glycation effects relevant to anti-aging skin careWell-tolerated; generally recognized as safe with a favorable skin compatibility profile
+ Tocopherol+ Ascorbic Acid
Humectant
Strelitzia Nicolai Seed Aril Extract

An extract from the seed aril of the white bird of paradise plant (Strelitzia nicolai), used as a skin-conditioning humectant ingredient.

humectantskin-conditioning
Supports skin hydration as part of a moisture-locking formula
Fragrance
Styrax Benzoin Resin Extract

A resin extract from the Styrax benzoin tree rich in benzoic acid and cinnamic acid derivatives, used primarily as a fragrance ingredient with secondary film-forming and soothing properties.

fragranceskin-conditioningsoothingfilm-former
Provides a warm, sweet, balsamic fragrance noteFilm-forming properties help protect the skin barrierMild soothing and skin-calming effect
Known fragrance sensitizer; contains benzoic acid and cinnamic acid derivatives that can trigger contact allergiesNot recommended for sensitive or fragrance-reactive skin
Soothing
Styrax Japonicus Branch/Fruit/Leaf Extract

A multi-part botanical extract from the branches, fruit, and leaves of Styrax japonicus (Japanese snowbell tree) providing polyphenols and triterpenes for antioxidant and soothing activity in cosmetic formulations.

soothingantioxidantskin conditioning
Rich in polyphenols and triterpenes with antioxidant and anti-inflammatory propertiesMulti-part harvest delivers a broader phytochemical profile than single-part extractsUsed in K-beauty for skin brightening and calming benefits
Potential for fragrance-related sensitization due to natural resinous compounds
Fragrance
Styrax Tonkinensis Resin Extract

Resin extract from Styrax tonkinensis (Siam benzoin), a Southeast Asian tree. Used in Caudalie's Beauty Elixir as a balsamic fragrance fixative. Contains benzoic and cinnamic acid esters.

fragranceantioxidant
Resinous extract from Styrax tonkinensis (Siam benzoin) with warm vanilla-balsamic fragrance notesContains benzoic acid, cinnamic acid esters, and vanillin with mild antioxidant activity
Contains cinnamic acid derivatives and benzoic acid — potential sensitizers for fragrance-sensitive individuals
Other
Styrene Isoprene Styrene Block Copolymer
Styrene/Isoprene Copolymer

A synthetic elastomeric block copolymer used as the pressure-sensitive adhesive matrix or flexible substrate in hydrocolloid and acne patch formulations, providing structural integrity and skin adhesion.

film-formingadhesiveviscosity-increasing
Provides flexible elastomeric substrate for acne patchesEnables conformable adhesion to skin contours
Inert polymer; no known skin activity or sensitization at typical patch-use concentrations