Kose Stephen Knoll Scalp Care System Hydrator 500ml

DESCRIPTION

What It Does: Provides the complete fragrance profile contributing to product sensory experience and consumer appeal.

Why It's Used: Fragrance is a major consumer purchase driver — up to 70% of consumers make purchasing decisions partially based on product scent.

How It Works: Fragrance blends interact with olfactory receptors providing the sensory profile — complex mixtures activate multiple receptor types for rich, multidimensional scent experiences.

Typically Found In: All fragrance products

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: Standard use levels

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

Ifra guidelines set usage limits for fragrance ingredients based on skin sensitisation and phototoxicity assessment for each application category.

Last Verified: Eu regulation 1223/2009 annex iii,ifra standards,fragrance allergen declaration requirements

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: Delivers targeted skin-conditioning or bioactive benefits through a specific mechanism of action suited to the formulation's intended purpose.

Why It's Used: Specialty actives address specific skin concerns through targeted molecular mechanisms, providing efficacy beyond what base formulation ingredients alone can achieve.

How It Works: The bioactive compound interacts with specific molecular targets in skin cells or the extracellular matrix — enzymes, receptors, structural proteins, or signaling molecules — triggering beneficial biological responses.

Typically Found In: Serums,treatments,moisturizers,specialty products

TECHNICAL DETAILS

Primary Category: Specialty actives

Secondary Functions: Skin-conditioning,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.01–5%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Specialty active ingredient; check individual sourcing for vegan status.

SKIN COMPATIBILITY

Irritancy Rating: 1

Comedogenicity Rating: 0

Sensitivity Concerns: Low sensitization potential at recommended use concentrations.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Well-characterized cosmetic ingredient with established safety profile. generally non-irritating at typical use concentrations. suitable for leave-on and rinse-off cosmetics.

Works Well With: Niacinamide,hyaluronic acid,vitamin c,peptides

Avoid Combining With: Incompatible with oxidizing agents; check ph stability

SCIENTIFIC NOTE

Specialty actives typically work through enzyme inhibition (e.g., tyrosinase inhibition for brightening, mmp inhibition for anti-aging), receptor activation (e.g., retinoid receptors, ppar-γ for barrier genes), or transcription factor modulation (e.g., nrf2 for antioxidant gene upregulation). structure-activity relationships determine potency and selectivity.

Last Verified: Cosing eu database; pcpc cosmetic ingredient safety reviews; ingredient-specific safety and efficacy literature

Primary Sources: 2025-01-15

DESCRIPTION

What It Does: Activates trpm8 cold thermoreceptors for intense cooling sensation and analgesic activity.

Why It's Used: The most potent cosmetic cooling agent – direct trpm8 agonist providing cooling sensation without actual temperature reduction for refreshing and analgesic formulations.

How It Works: Potent trpm8 (menthol receptor/cold thermosensor) agonist – activation at room temperature mimics cold sensation without actual cooling. anti-pruritic via trpm8 activation competing with itch c-fiber signaling. antimicrobial via membrane disruption.

Typically Found In: Cooling products,scalp treatments,oral care,pain relief,foot care,after-sun

TECHNICAL DETAILS

Primary Category: Active ingredient – cooling sensory terpenoid

Secondary Functions: Redness reduction,anti-inflammatory,calming

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 – from mentha piperita or synthetic

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 2/5 – low to moderate; potential sensitizer

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; ideal for reactive and sensitive skin.

Safe for Sensitive Skin: Avoid near eyes. use with caution at concentrations above 1% for sensitive skin.

SAFETY & COMPATIBILITY

Safety Profile: Eu max 4.5% (leave-on); regulations vary by application site. avoid on infants' face.

Works Well With: Ceramides,panthenol,allantoin,hyaluronic acid,centella asiatica

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Menthol's exceptional cooling potency stems from its ec50 for trpm8 activation of approximately 10μm (vs camphor's ec50 of ~5mm – 500× lower potency). this 500× potency advantage explains why even tiny concentrations of menthol provide intense cooling, while much higher concentrations of camphor are required for equivalent sensation.

Last Verified: Cosing database,mckemy et al. menthol trpm8 discovery,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

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

Last Verified: Cosing database,methylparaben technical literature

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides antioxidant protection, soothing anti-inflammatory effects, and skin-conditioning benefits through plant-derived polyphenols and phytochemicals.

Why It's Used: Plant extracts concentrate bioactive phytochemicals evolved for environmental protection — uv, microbial, and oxidative stressors — that translate to skin benefits.

How It Works: Polyphenols (flavonoids, phenolic acids) inhibit nf-κb-mediated inflammatory signaling, scavenge reactive oxygen species through electron donation, and chelate pro-oxidant metal ions to reduce oxidative skin damage.

Typically Found In: Serums,toners,moisturizers,masks,essences

TECHNICAL DETAILS

Primary Category: Botanical extracts

Secondary Functions: Antioxidant,anti-inflammatory

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: Yes

Halal Status: Yes

Source Notes: Plant-derived extract; no animal components.

SKIN COMPATIBILITY

Irritancy Rating: 1899-12-31 00:00:00 -0800

Sensitivity Concerns: Low sensitization potential at recommended use concentrations.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Well-characterized cosmetic ingredient with established safety profile. generally non-irritating at typical use concentrations. suitable for leave-on and rinse-off cosmetics.

Works Well With: Niacinamide,hyaluronic acid,vitamin c,ceramides

Avoid Combining With: Strong oxidizing agents

SCIENTIFIC NOTE

Plant secondary metabolites (flavonoids, terpenes, phenolic acids) are biosynthesized as defense compounds against uv, herbivores, and pathogens. their anti-inflammatory activity typically derives from competitive inhibition of cox-2 and 5-lox enzymes (ic50 1–50 µm), while antioxidant activity involves single electron transfer (set) and hydrogen atom transfer (hat) mechanisms with structure-dependent rate constants.

Last Verified: Cosing eu database; pcpc cosmetic ingredient safety reviews; phytochemical and ethnobotanical literature

Primary Sources: 2025-01-15

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 film-forming conditioning and detangling with heat protection in a polymer that adsorbs substantively to hair.

Why It's Used: The most widely used cationic polymer conditioner – provides excellent conditioning and detangling while adsorbing strongly to damaged hair areas that need conditioning most.

How It Works: Cationic quaternary ammonium groups along the polymer backbone adsorb to anionic sites on hair keratin. higher charge density on damaged hair (more negative sites) leads to preferential adsorption where conditioning is needed. polymer film formation provides heat protection and volume.

Typically Found In: Shampoos,2-in-1 products,conditioners,styling products

TECHNICAL DETAILS

Primary Category: Functional ingredient – cationic polymer conditioner

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 – cellulose-derived

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

Polyquaternium-10's 'self-targeting' to damaged hair sites is a unique smart conditioning mechanism. as hair damage increases negative charge density by exposing keratin's aspartate and glutamate carboxylate groups, pq-10's cationic polymer backbone adsorbs preferentially to these high-charge damage sites – automatically delivering more conditioning where the hair needs it most.

Last Verified: Cosing database,robbins hair science,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Deposits a conditioning film on hair and skin through electrostatic attraction to negative cuticle/corneocyte surfaces, reduces hair-on-hair friction for improved combability and detangling, eliminates static charge buildup, and provides anti-frizz humidity resistance.

Why It's Used: Cationic polymers are the primary hair conditioning technology — the permanent positive quaternary ammonium groups provide substantive deposition that resists rinsing, delivering persistent conditioning between washes unlike small-molecule cationic conditioners.

How It Works: At shampoo/conditioner ph 4.5–5.5, hair cuticle carries net negative charge (isoelectric point ph ~3.5). polyquaternium cations undergo electrostatic attraction depositing on the cuticle surface. during rinsing, the deposited polymer film persists from reduced surface-solution equilibrium at low bulk concentration — substantive deposition from favourable interfacial versus bulk partitioning.

Typically Found In: Shampoos,conditioners,leave-in products

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%–3%

SOURCING & ETHICS

Vegan Status: Yes

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

Different polyquaternium numbers indicate different backbone chemistries: pq-7 (acrylamide/quaternary acrylate copolymer) for leave-on flexibility; pq-10 (hydroxyethylcellulose/quaternary ammonium) for substantive deposition; pq-11 (vp/dimethylaminoethyl methacrylate) for styling fixation.

Last Verified: Cosing database,polyquaternium-7 cationic conditioning deposition review

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