Vitamin C Ester Brightening Overnight Treatment

DESCRIPTION

What It Does: Provides humectant hydration and active ingredient solubilization with excellent skin feel.

Why It's Used: Preferred glycol humectant in premium and k-beauty formulations for superior skin feel vs propylene glycol with equivalent functionality.

How It Works: Two hydroxyl groups at 1,3-positions provide water binding and solvent activity. better tolerated than propylene glycol with minimal sensitization risk. 4-carbon backbone provides slightly greater hydrophobic character enabling dissolution of less polar actives vs pg.

Typically Found In: Toners,essences,serums,k-beauty formulas

TECHNICAL DETAILS

Primary Category: Functional ingredient – glycol humectant

Secondary Functions: Tewl reduction,skin plumping

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–10%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Synthetic or naturally derived. excellent aqueous solubility.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; suitable for all skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Ceramides,emollients,occlusives,glycerin,hyaluronic acid

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

K-beauty's preference for butylene glycol over propylene glycol is driven by two factors: bg's superior skin feel (less tacky than pg's higher viscosity) and its lower sensitization potential (1,3-bg has better spatial distribution of hydroxyl groups that reduces protein interaction vs pg's 1,2-position oh groups).

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides fatty alcohol emulsification and thickening for stable, well-textured emulsions.

Why It's Used: The most widely used fatty alcohol in cosmetics – provides emulsification, thickening, and emolliency simultaneously from a single ingredient with excellent safety profile.

How It Works: Forms bilayer lamellar structures in water with emulsifiers creating a viscous structured network that thickens and stabilizes emulsions. fatty alcohol emolliency provides direct skin conditioning. bilayer formation reduces inter-droplet coalescence in emulsions.

Typically Found In: Creams,lotions,conditioners – virtually all emulsion products

TECHNICAL DETAILS

Primary Category: Functional ingredient – fatty alcohol emulsifier/thickener

Secondary Functions: Barrier sealing,softening

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–25%

SOURCING & ETHICS

Vegan Status: Yes – from vegetable or coconut/palm fatty acids

Halal Status: Yes

Source Notes: Plant-derived, synthetic or animal-derived. verify source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Cetearyl alcohol's ability to form lamellar liquid crystal structures ('krafft phases') with water and co-emulsifiers provides not only emulsion stability but also enhanced skin penetration via the lamellar skin barrier pathway. these crystalline structures can act as a reservoir for active ingredients, slowly releasing them as the lamellar structure melts on skin contact.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides maximum aha efficacy from the smallest most penetrating alpha-hydroxy acid.

Why It's Used: The most potent aha — glycolic acid's smallest molecular size provides the deepest penetration and highest efficacy of any alpha-hydroxy acid for exfoliation and anti-aging.

How It Works: Smallest aha (mw 76) provides deepest stratum corneum penetration. disrupts corneodesmosomes reducing cohesion. stimulates fibroblast collagen i and iii synthesis. efficacy is ph-dependent — free acid fraction determines activity.

Typically Found In: Chemical peels,body lotions,anti-aging serums,exfoliating toners

TECHNICAL DETAILS

Primary Category: Active ingredient – primary aha

Secondary Functions: Brightening,collagen stimulation

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–10% cosmetic; higher professional

SOURCING & ETHICS

Vegan Status: Yes – synthetic or fermentation-derived

Halal Status: Yes

Source Notes: Fermentation-derived or synthetic. ph must be ≤4.0 for aha activity.

SKIN COMPATIBILITY

Irritancy Rating: 2/5 – low to moderate

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Photosensitizing – mandatory spf use. start at low frequency.

Safe for Sensitive Skin: Use with caution – spf required

SAFETY & COMPATIBILITY

Safety Profile: Eu cosmetics: max 10% leave-on, ph ≥3.5, mandatory sun protection advisory. professional peel concentrations regulated separately.

Works Well With: Niacinamide,ceramides,hyaluronic acid,spf

Avoid Combining With: Retinol in same step; multiple exfoliants simultaneously

SCIENTIFIC NOTE

Glycolic acid's ph-dependent efficacy is critical: at ph 3.0 ~100% is in the free acid (membrane-permeable) form; at ph 3.5 ~70%; at ph 4.0 ~50%. the eu ph ≥3.5 requirement reduces free acid proportion, lowering efficacy but also reducing irritation — why professional peel concentrations at lower ph are far more active than equivalent cosmetic concentrations.

Last Verified: Cosing database,eu aha guidelines,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Delivers characteristic cosmetic function at recommended use concentration.

Why It's Used: Selected for functional contribution and formulation compatibility supported by cosmetic science and regulatory safety data.

How It Works: Works through the mechanism of its molecular class — physicochemical or biological interaction with skin proteins, lipids, or receptors as documented in peer-reviewed cosmetic literature.

Typically Found In: Skin care formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – cosmetic active

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–10%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Isopropyl palmitate has an established safety and efficacy profile within the cosmetic regulatory framework at standard use concentrations.

Last Verified: Cosing database,isopropyl palmitate technical literature

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Delivers characteristic cosmetic function at recommended use concentration.

Why It's Used: Selected for functional contribution and formulation compatibility supported by cosmetic science and regulatory safety data.

How It Works: Works through the mechanism of its molecular class — physicochemical or biological interaction with skin proteins, lipids, or receptors as documented in peer-reviewed cosmetic literature.

Typically Found In: Skin care formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – cosmetic active

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–10%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Sodium carboxymethyl beta-glucan has an established safety and efficacy profile within the cosmetic regulatory framework at standard use concentrations.

Last Verified: Cosing database,sodium carboxymethyl beta-glucan technical literature

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Delivers potent, stable vitamin c deep into skin for superior antioxidant protection and collagen stimulation.

Why It's Used: Premium anti-aging requiring proven deep penetration and exceptional stability in all formulation types.

How It Works: Four hexyl decyl chains provide lipophilicity for membrane penetration. progressive enzymatic hydrolysis releases ascorbic acid within deeper skin layers.

Typically Found In: Luxury vitamin c serums,anti-aging products,brightening formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – vitamin c derivative

Secondary Functions: Superior penetration,stable vitamin c

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–3%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Fully synthetic. produced by esterification of ascorbic acid with 2-hexyl decanol.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; suitable for all skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Tocopherol,ferulic acid,niacinamide,spf

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Clinical studies confirm thd reaches the dermis more effectively than l-ascorbic acid, stimulating fibroblast collagen production at the structural skin level.

Last Verified: Cosing database,shefer et al. penetration studies

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Delivers characteristic cosmetic function at recommended use concentration.

Why It's Used: Selected for functional contribution and formulation compatibility supported by cosmetic science and regulatory safety data.

How It Works: Works through the mechanism of its molecular class as documented in peer-reviewed cosmetic literature.

Typically Found In: Skin care formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – cosmetic active

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–10%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Triethanolamine has an established safety profile within the cosmetic regulatory framework at standard use concentrations.

Last Verified: Cosing database,triethanolamine technical literature

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides melanin precursor support for tanning acceleration and nmf conditioning.

Why It's Used: Tanning accelerator amino acid — l-tyrosine as the direct tyrosinase substrate supports enhanced melanin production for accelerated self-tanning when combined with uv exposure.

How It Works: Direct tyrosinase substrate for melanin synthesis (tyrosine → dopa → melanin). providing excess substrate theoretically accelerates melanogenesis during uv exposure. nmf component via phenol + carboxylate water binding. structural component of collagen tyrosine residues for crosslink formation.

Typically Found In: Tanning accelerators,nmf products,skin conditioning

TECHNICAL DETAILS

Primary Category: Active ingredient – melanogenesis amino acid

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–5%

SOURCING & ETHICS

Vegan Status: Yes – fermentation

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

L-tyrosine's use in tanning accelerators is based on the pharmacological principle of substrate excess driving enzyme velocity: if tyrosinase activity (and therefore melanin synthesis rate) is substrate-limited by available tyrosine, providing excess substrate substrate accelerates the reaction rate (following michaelis-menten kinetics). however, melanogenesis is primarily regulated by uv-induced melanocyte signalling rather than substrate availability — limiting tyrosine's actual tanning acceleration efficacy.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: At 2–10%: provides deep humectancy, softens sc, and improves other active penetration. at 10–40%: keratolytically dissolves corneocyte protein bonds for intensive exfoliation of hyperkeratotic skin (calluses, eczema plaques, psoriasis).

Why It's Used: Urea combines two otherwise separate ingredient classes (humectant and keratolytic) in one molecule, with formulator-controlled function through concentration selection — uniquely versatile for multiple skin condition applications.

How It Works: Urea's carbonyl and amine groups form h-bonds with water (humectancy) and with corneocyte keratin (penetration). at high concentrations, urea disrupts keratin hydrogen bonds (chaotropic activity) solubilising the sc protein matrix — concentration determines whether humectant or keratolytic effect predominates.

Typically Found In: Eczema,hyperkeratosis,callus care,moisturising

TECHNICAL DETAILS

Primary Category: Functional ingredient – humectant

Secondary Functions: Tewl reduction,skin plumping

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 2%–40%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Synthetic or naturally derived. excellent aqueous solubility.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; suitable for all skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Ceramides,emollients,occlusives,glycerin,hyaluronic acid

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Urea is the most concentrated natural nmf component — healthy sc contains 28 mg/g urea versus 2 mg/g in xerotic (dry) skin. topical urea application directly replenishes the physiological nmf deficit that drives dry skin conditions.

Last Verified: Cosing database,urea nmf dual function humectant keratolytic review

Primary Sources: 2026-03-12