Hada Labo Kotojyun Instant Hydra Mask 1S

DESCRIPTION

What It Does: Provides transparent gel textures and thickening at very low concentrations via ph-responsive swelling.

Why It's Used: The most widely used gel thickener – provides crystal-clear, stable gels at concentrations as low as 0.1-0.5% with ph-controlled viscosity.

How It Works: Highly crosslinked polyacrylic acid remains tightly coiled at acidic ph. neutralization with naoh or triethanolamine ionizes carboxylic groups causing electrostatic repulsion that unfolds and swells the polymer coils, dramatically increasing viscosity. concentration-dependent thickening.

Typically Found In: Gels,serums,emulsions,sunscreens

TECHNICAL DETAILS

Primary Category: Functional ingredient – polyacrylic acid thickener

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%–2%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

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

Carbomer's ph-responsive swelling mechanism provides an elegant formulation control tool: a neutralized gel can be liquefied by ph reduction (adding acid) and re-thickened by reneutralization. this reversible rheology control allows two-phase products that mix on application without the need for mechanical emulsification.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides gram-negative focused preservation complementary to phenoxyethanol for comprehensive spectrum coverage.

Why It's Used: Phenoxyethanol complement — chlorphenesin's gram-negative and antifungal coverage complements phenoxyethanol's gram-positive activity for full-spectrum preservation at lower individual concentrations.

How It Works: 4-chlorophenol ether glycol disrupts bacterial and fungal membranes. strong gram-negative activity (pseudomonas, e. coli). good candida antifungal activity. used with phenoxyethanol for synergistic broad-spectrum coverage. ph stable 3-9.

Typically Found In: Comprehensive preservation systems,baby products (low concentration)

TECHNICAL DETAILS

Primary Category: Functional ingredient – glycerol ether preservative

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%–0.3%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

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: Eu max 0.3% cosmetics. good safety profile. synergistic combination with phenoxyethanol (0.3% pe + 0.1% chlorphenesin often equivalent to 1% pe alone).

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Chlorphenesin + phenoxyethanol synergy operates through a classic spectrum-filling combination: phenoxyethanol provides strong gram-positive antimicrobial activity while chlorphenesin provides gram-negative and antifungal coverage. the combination's minimum inhibitory concentration sum is subadditive (provides equivalent preservation at combined concentrations below what either alone would require) — textbook pharmacological synergy enabling lower total preservative load.

Last Verified: Cosing database,eu preservative annex v,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides essential barrier sterol function as one of three critical stratum corneum lipid components.

Why It's Used: Essential component of complete barrier repair formulations – the stratum corneum barrier requires ceramides:cholesterol:fatty acids in approximately 1:1:1 molar ratio for complete barrier restoration.

How It Works: Integrates between ceramide headgroups in lamellar body structures, providing fluidity and flexibility to the otherwise rigid ceramide-dominated lipid matrix. controls lamellar body phase behavior for functional barrier.

Typically Found In: Barrier repair moisturizers,eczema treatments,dry skin formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – barrier sterol

Secondary Functions: Lamellar body structure,barrier sterol

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.01%–1%

SOURCING & ETHICS

Vegan Status: Conditional – animal-derived (lanolin) or plant-derived phytosterol analogs; verify

Halal Status: Conditional – verify source

Source Notes: Traditionally from lanolin (wool grease). plant-derived cholesterol alternatives include phytosterols, though these show slightly different barrier integration. verify for vegan/halal.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Endogenous molecule; excellent tolerability.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Exceptional safety profile. natural skin component. ewg score: 1.

Works Well With: Other ceramides,cholesterol,free fatty acids,hyaluronic acid,niacinamide

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Elias demonstrated that barrier repair requires all three lipid classes (ceramides, cholesterol, fatty acids) in approximately equimolar ratios. formulations providing only ceramides without cholesterol and fatty acids show significantly inferior barrier restoration vs complete triple-lipid combinations.

Last Verified: Cosing database,elias et al. barrier lipid ratio study,loden barrier repair review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Glycerin pulls water from the environment and deeper skin layers into the outer skin layer (epidermis), boosting moisture levels and keeping skin soft, smooth, and plump.

Why It's Used: It is used in virtually every moisturizer, serum, and cleanser because it is highly effective at hydrating skin, is well-tolerated by all skin types, and enhances the texture and spreadability of formulations.

How It Works: As a humectant, glycerin forms hydrogen bonds with water molecules, trapping them in the skin. it also reinforces the skin barrier by integrating into lipid structures between skin cells.

Typically Found In: Moisturizers,serums,cleansers,toners,sheet masks,sunscreens,body lotions,shampoos,conditioners

TECHNICAL DETAILS

Primary Category: Humectant

Secondary Functions: Skin barrier support,emollient,solvent

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–30% (typical: 3–10%)

SOURCING & ETHICS

Vegan Status: Yes – plant-derived (coconut, soy, palm) or synthetic

Halal Status: Yes – when plant-derived or synthetic; verify source with supplier

Source Notes: Derived from plant oils via hydrolysis or saponification; synthetic versions also available. palm-derived glycerin carries sustainability concerns.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low; non-irritating at all standard concentrations

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Extremely rare allergic reactions; generally safe for all skin types including sensitive and baby skin

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Widely recognized as safe. ewg hazard score: 1. no significant concerns for irritation, sensitization, or toxicity at typical concentrations (up to 50%).

Works Well With: Hyaluronic acid,ceramides,niacinamide,panthenol,urea,peptides,retinol,ahas/bhas

Avoid Combining With: No known incompatibilities at standard concentrations

SCIENTIFIC NOTE

Glycerin is an endogenous skin component found naturally in the stratum corneum. aquaporin-3 channels in keratinocytes facilitate glycerin transport, making it integral to natural skin hydration pathways.

Last Verified: Cosing database,cir safety assessment,ewg skin deep,inci decoder

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Prevents microbial contamination and spoilage in cosmetic formulations.

Why It's Used: The benchmark cosmetic preservative – eu-permitted up to 1%, effective against virtually all cosmetically relevant microorganisms, and excellent tolerability.

How It Works: Phenol ring provides broad antimicrobial activity via disruption of bacterial and fungal cell membranes and inhibition of enzymatic activity. effective against gram-positive and gram-negative bacteria, yeasts (candida), and molds (aspergillus). activity ph range: 3-9.

Typically Found In: All cosmetic formulations as primary preservative

TECHNICAL DETAILS

Primary Category: Functional ingredient – broad-spectrum preservative

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%–1% (eu max 1%)

SOURCING & ETHICS

Vegan Status: Yes – synthetic

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: Eu cosmetics regulation max 1%. sccs assessed as safe at ≤1%. avoid use around eyes in baby products per some country regulations. ewg score: 4.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Phenoxyethanol's widespread adoption as the primary cosmetic preservative followed the phaseout of parabens from many formulations in the 2000s-2010s. despite having a comparable or better safety profile to parabens, it is often cited in 'free-from' formulations – a consumer perception issue rather than a scientific safety concern.

Last Verified: Cosing database,sccs opinion on phenoxyethanol,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides antimicrobial activity against p. acnes and s. aureus while supporting ceramide synthesis and reducing inflammation.

Why It's Used: Used in acne and sensitive skin formulations for combined antimicrobial, anti-inflammatory, and barrier repair activity from a single plant-derived sphingoid base.

How It Works: Trihydroxy structure provides stronger antimicrobial activity vs sphingosine. substrate for ceramide synthase to form phytoceramides. reduces pro-inflammatory cytokine production in keratinocytes.

Typically Found In: Anti-acne products,sensitive skin treatments,barrier repair formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – plant sphingoid base

Secondary Functions: Anti-acne,ceramide synthesis,anti-inflammatory

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.01%–0.5%

SOURCING & ETHICS

Vegan Status: Yes – plant/yeast-derived

Halal Status: Yes

Source Notes: Derived from yeast (pichia) fermentation or plant sphingolipid hydrolysis. fully plant-derived.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Endogenous molecule; excellent tolerability.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Exceptional safety profile. natural skin component. ewg score: 1.

Works Well With: Other ceramides,cholesterol,free fatty acids,hyaluronic acid,niacinamide

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Phytosphingosine's additional 4-hydroxy group (vs sphingosine) significantly enhances antimicrobial activity while maintaining ceramide precursor function. clinically demonstrated to reduce p. acnes counts and inflammatory lesions in acne studies.

Last Verified: Cosing database,lintner phytosphingosine review,kawano et al. ceramide precursor study

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides endogenous-skin-identical emolliency with exceptional stability and skin compatibility.

Why It's Used: The most skin-compatible emollient – chemically identical to human sebum squalene component with outstanding tolerability across all skin types.

How It Works: Fully saturated hydrocarbon with zero oxidation sites provides exceptional stability unlike squalene's 6 double bonds. integrates into stratum corneum lipid bilayers with near-perfect biocompatibility. provides antioxidant protection to formulation via radical quenching.

Typically Found In: Facial oils,serums,non-comedogenic moisturizers,luxury body care

TECHNICAL DETAILS

Primary Category: Functional ingredient – emollient

Secondary Functions: Maximum biocompatibility,antioxidant stabilizer,non-comedogenic

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–100%

SOURCING & ETHICS

Vegan Status: Conditional – plant-derived (sugarcane, olive) preferred; shark liver-derived being phased out

Halal Status: Yes – plant-derived

Source Notes: Sustainable plant-derived squalane from sugarcane fermentation (amyris) or olive oil fractionation is preferred over shark liver-derived. chemically identical regardless of source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

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

Squalene constitutes approximately 12-15% of human sebum – the highest proportion of any skin lipid. topical squalane (stable, hydrogenated form) replenishes this abundant endogenous skin lipid. the complete absence of oxidizable double bonds (unlike squalene's 6 double bonds) eliminates the pro-oxidant concerns of natural squalene oxidation.

Last Verified: Cosing database,huang et al. squalane review,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides the universal solvent and vehicle for water-soluble actives and the continuous phase of all o/w emulsions.

Why It's Used: The most essential cosmetic ingredient — aqua (water) is listed first on virtually all water-containing cosmetic inci labels as the highest-concentration ingredient, serving as the foundation of the global cosmetics industry.

How It Works: Acts as solvent for all water-soluble ingredients (glycols, amino acids, water-soluble actives). forms the continuous external phase of o/w emulsions (lotions, creams, serums). provides aqueous environment for enzymatic and chemical reactions between actives. ph adjustment medium.

Typically Found In: Virtually all cosmetic products — the most universal cosmetic ingredient globally

TECHNICAL DETAILS

Primary Category: Functional ingredient – water

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: Varies widely — up to 95% in some toners and serums

SOURCING & ETHICS

Vegan Status: Yes – water (deionised/purified)

Halal Status: Yes

Source Notes: Cosmetic-grade water is purified (deionised, distilled, or ro filtered) to prevent mineral content interference with formulation stability. european pharmacopoeial water (aqua purificata ph. eur.) is the quality standard for pharmaceutical and high-end cosmetic formulations.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – non-irritant

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

Water's position as the first inci ingredient on most cosmetic labels reflects the regulatory requirement to list ingredients in descending concentration order — meaning water is the most abundant ingredient in the majority of cosmetic products. the fundamental role of water as the universal cosmetic solvent and vehicle makes it simultaneously the most important cosmetic ingredient and the one that requires the most sophisticated formulation chemistry to control — every emulsifier, thickener, preservative, and ph adjuster exists primarily to manage water's interaction with other ingredients in formulation.

Last Verified: Cosing database,eu cosmetics regulation 1223/2009 inci requirements,ph. eur. aqua purificata monograph

Primary Sources: 2026-03-12