The library

Ingredient library

Every ingredient SkinAtlas knows about — all 2165 of them. What each one does, what it works well with, and what to watch for.

130 ingredients matching "acid" — page 2 of 6

Barrier support
Ceramide AG
CERAMIDE AG

Ceramide AG is the INCI name for Ceramide 6-II, characterized by an alpha-hydroxy fatty acid (A) and dihydrosphingosine (G). One of the naturally occurring ceramides in the stratum corneum. Used in multi-ceramide formulations (Matsuyama Hadauru, Kiku-Masamune, Ishizawa) to restore barrier.

barrier-supportskin-conditioning
Key skin barrier lipid — reduces transepidermal water lossRestores damaged barrierCeramide 6 (AG) type
+ Ceramide NP+ Ceramide EOP+ Cholesterol
Emollient
Cholesteryl/Octyldodecyl Lauroyl Glutamate
CHOLESTERYL/OCTYLDODECYL LAUROYL GLUTAMATE

An ester of N-lauroyl glutamic acid with cholesterol and octyldodecanol. Forms liquid crystalline structures that mimic the skin's lamellar lipid matrix, integrating and reinforcing barrier function. Used in Naturie's Hatomugi gel and milk for barrier-compatible emolliency.

emollientbarrier-supportskin-conditioning
Liquid crystal-forming — integrates into skin's lamellar structureStrengthens barrier functionElegant, non-greasy emolliency
+ Ceramide NP+ Squalane+ Hyaluronic Acid
Exfoliant
Citric Acid

An AHA most often used in small amounts to adjust pH.

ahaph-adjuster
Mild exfoliationAdjusts formula pH
Can irritate at exfoliating concentrations
Surfactant
Coconut Acid

A mixture of fatty acids derived from coconut oil (primarily lauric, myristic, and capric acids) used as a surfactant, emulsifier, and emollient in cleansers and creams.

surfactantemulsifieremollient
Provides cleansing and lather when saponifiedSoftens and conditions skin
Humectant
Collagen Amino Acids
Hydrolyzed Collagen Amino Acids

The free amino acid mixture released by complete hydrolysis of collagen, used as a humectant and skin-conditioning agent.

humectantconditioningamino-acid
Attracts and retains moistureConditions the skin surfaceSupplies the key amino acids (glycine, proline, hydroxyproline) that make up skin's own collagen
Other
Cyclobutanetetracarboxylic Acid
CYCLOBUTANETETRACARBOXYLIC ACID

A small molecule with four carboxylic acid groups arranged around a cyclobutane ring. Functions as a chelating agent, binding metal ions that would otherwise catalyze oxidative degradation of active ingredients. Found in Elixir Reflet SPF50+ as a stability enhancer.

chelating-agent
Metal ion chelator — prevents oxidative degradationEnhances preservative system efficacy
+ Phenoxyethanol+ BHT
Humectant
Cysteine

A sulfur-containing amino acid that acts as a humectant and antioxidant in cosmetics, contributing to skin hydration and supporting the skin's own defense mechanisms.

humectantamino-acidantioxidant
Attracts and retains moistureSupports the skin's natural moisturizing factor (NMF)Antioxidant via thiol group
Other
Cystine

The oxidized dimer of cysteine formed by a disulfide bond between two cysteine molecules; used in cosmetics as a conditioning amino acid with roles in keratin integrity and as a precursor to antioxidant glutathione — distinct from cysteine (the monomer free thiol form).

Skin conditioningAmino acidAntioxidant precursor
Supports keratin and hair protein structure via disulfide bondsPrecursor to glutathione antioxidant systemConditions skin
Active
DNA-Na
SODIUM DNA

The sodium salt of deoxyribonucleic acid (DNA), typically sourced from salmon milt (sperm). Highly hydrophilic — attracts and retains moisture. Also promotes skin cell repair mechanisms. Used in Lululun's Hydra PD mask.

skin-conditioninghumectantantioxidant
Excellent moisture retention — highly hydrophilicPromotes skin barrier repairAntioxidant and anti-inflammatory
+ Hyaluronic Acid+ Niacinamide
Preservative
Dehydroacetic Acid

A naturally derived cyclic lactone preservative approved for both conventional and Ecocert/COSMOS-certified natural cosmetics, effective against bacteria and fungi.

preservative
Effective against bacteria and fungi at low concentrations (≤0.6%)Approved by Ecocert/COSMOS for natural/organic formulations
CIR assessed as safe; non-irritating and non-sensitizing in clinical testsOften paired with benzyl alcohol for broader spectrum coverage
Emollient
Diglyceryl Adipate Mixed Fatty Acid Esters
DIGLYCERYL ADIPATE MIXED FATTY ACID ESTERS

A mixed ester of diglycerin and adipic acid with fatty acids. Used as a lightweight emollient in Elixir Retino Power Cream.

emollientskin-conditioning
Smooth, elegant emollientSkin conditioning
+ Squalane+ Castor Oil
Emollient
Dimer Dilinoleic Acid (Phytosteryl/Isostearyl/Cetyl/Stearyl/Behenyl)

A polymeric ester formed from dimerized linoleic acid esterified with a blend of phytosterols, isostearyl, cetyl, stearyl, and behenyl groups. Used in premium formulas for rich emolliency.

emollientskin-conditioningviscosity-controlling
Complex ester of dimerized linoleic acid with multiple fatty alcohols and phytosterolsRich emollient providing a luxurious skin feel while maintaining spreadability; structurally similar to natural skin lipids
Emollient
Dipentaerythrityl Fatty Acid Ester
DIPENTAERYTHRITYL FATTY ACID ESTER

An ester of dipentaerythritol and a blend of fatty acids. Functions as a lightweight, non-greasy emollient that provides a silky, dry-touch skin feel; also improves formula stability.

emollientskin-conditioning
Long-lasting emollient feelNon-greasy and dry-touchFormula stabilizer
+ Dimethicone+ Squalane
Emollient
Dipentaerythrityl Hexa C5-9 Acid Esters

A mixed ester of dipentaerythritol with C5–C9 branched-chain fatty acids, used as a lightweight emollient and texture modifier. It provides a dry, silky skin feel without the heaviness of conventional oils, commonly used in light-feel formulas and primers.

emollientskin-conditioningtexture-enhancing
Lightweight, non-greasy emollient that imparts a silky, velvety skin feelSpreads easily without occlusion, suitable for light moisturisers and serumsImproves skin texture and formula application
Active
Dipotassium Ursolyl Phosphate
DIPOTASSIUM URSOLYL PHOSPHATE

A water-soluble phosphate salt derivative of ursolic acid, a pentacyclic triterpenoid found in rosemary and other botanicals. Developed for improved delivery of ursolic acid's anti-aging and anti-inflammatory benefits.

anti-agingskin-conditioning
Anti-aging firming activityReduces the appearance of wrinklesImproves skin elasticity
+ Glycerin+ Butylene Glycol
Antioxidant
Ethyl Ascorbyl Ether

A stable, both water- and oil-compatible vitamin C derivative that converts to ascorbic acid in skin. Valued for brightening with good formula stability.

antioxidantbrightening
BrightensEvens toneAntioxidant protection
+ Niacinamide+ Tocopherol+ Ferulic Acid
Emollient
Ethyl Oleate
ETHYL OLEATE

The ethyl ester of oleic acid used as a lightweight, penetrating emollient and delivery solvent in skincare formulas.

emollientskin-conditioningsolvent
Lightweight emollient with excellent skin penetrationEnhances delivery of active ingredientsNon-greasy skin feel
+ Glycerin+ Cetearyl Alcohol
Barrier support
Fatty Acids

A collective term for free fatty acids found in the skin's stratum corneum lipid matrix. Together with ceramides and cholesterol they form the lamellar bilayer that controls skin barrier function and water retention.

barrier-supportemollient
One of the three key lipids in the skin barrier (with ceramides and cholesterol)Reduce transepidermal water lossReinforce lipid bilayer structure
+ Ceramide NP+ Cholesterol+ Ceramide
Antioxidant
Ferulic Acid

A plant antioxidant that stabilizes and boosts vitamins C and E.

AntioxidantStabilizes vitamin CBoosts UV protection
+ Ascorbic Acid+ Tocopherol
Active
Folic Acid

Vitamin B9 (pteroylglutamic acid) used in cosmetics as an antioxidant and skin-conditioning agent that supports cellular renewal.

antioxidantskin-conditioningcell-communicating
Antioxidant that neutralises free radicalsSupports cellular turnover and DNA repair processesSkin-conditioning at low concentrations
Other
Formic Acid

The simplest carboxylic acid. In cosmetics, listed at trace levels (typically at the end of amino acid complex formulas) as a pH adjuster. Safe at the very low concentrations used in skincare.

pH adjusterpreservative
Irritating to skin and mucous membranes at higher concentrations; safe at cosmetic use levels
Exfoliant
Gluconolactone

A polyhydroxy acid (PHA) that exfoliates gently and hydrates.

pha
Gentle exfoliationAntioxidantSuitable for sensitive skin
Humectant
Glutamic Acid

A naturally occurring amino acid that functions as a humectant and contributes to the skin's natural moisturizing factor.

humectantamino-acid
Attracts and retains moistureComponent of the skin's natural moisturizing factor (NMF)
Other
Glutamine

A free-form amino acid (L-glutamine) used in cosmetics as a skin-conditioning agent and component of amino acid complex formulas; distinct from acetyl glutamine which is the N-acetylated form with different stability and activity profile.

Skin conditioningAmino acidBarrier support
Supports keratinocyte function and skin barrier proteinsConditions skin as part of amino acid complexesSubstrate for glutathione synthesis