Redken Extreme Length Leave-In Conditioner

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: Provides amino group-mediated preferential adsorption to damaged hair for targeted conditioning.

Why It's Used: Premium hair conditioning silicone – amino groups provide substantive adsorption to hair far exceeding pdms, with automatic targeting to the most damaged areas requiring conditioning.

How It Works: Amino (nh2) groups on silicone chain provide cationic character at normal ph, electrostatic adsorption to anionic hair surface. higher charge density at damaged sites increases adsorption where conditioning is most needed. si-o-si backbone provides permanent conditioning film with heat protection.

Typically Found In: Intensive conditioners,anti-frizz products,damage repair conditioners

TECHNICAL DETAILS

Primary Category: Functional ingredient – amino-functional silicone

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%–5%

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

Amodimethicone's amino group-driven substantivity to damaged hair is dramatically greater than non-functionalized pdms. studies show amodimethicone deposits 50-200× more mass on bleach-damaged hair vs virgin hair, providing an automatic 'damage detection' conditioning system that directs the most conditioning to the hair areas that need it most.

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

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Conditions skin, attracts moisture, supports wound healing, and improves microcirculation via no synthesis.

Why It's Used: Multi-functional amino acid for skin hydration, conditioning, and wound healing in peptide and nmf formulations.

How It Works: Guanidinium group binds water (humectant). substrate for nitric oxide synthase (enos) producing nitric oxide that vasodilates capillaries improving skin nutrition. stimulates fibroblast proliferation for wound healing.

Typically Found In: Anti-aging serums,wound healing products,nmf moisturizers,scalp treatments

TECHNICAL DETAILS

Primary Category: Active ingredient – amino acid

Secondary Functions: Wound healing,microcirculation,nmf component

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 – plant-derived or synthetic

Halal Status: Yes

Source Notes: Fermentation-derived or synthetic. natural skin component.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; endogenous skin molecule.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Hyaluronic acid,ceramides,peptides,other amino acids

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Arginine is a conditionally essential amino acid in wound healing where local demand exceeds synthesis capacity. topical arginine provides the nos substrate locally for no-mediated vasodilation and immune cell function in healing tissue.

Last Verified: Cosing database,cir safety assessment,witte & barbul arginine wound healing review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Supports keratin production for stronger hair and nails.

Why It's Used: Hair and nail keratin infrastructure support; widely marketed despite evidence being primarily oral supplementation-based.

How It Works: Coenzyme for carboxylase enzymes essential for fatty acid synthesis and amino acid metabolism relevant to hair follicle function.

Typically Found In: Hair growth shampoos,nail treatments,multivitamin products

TECHNICAL DETAILS

Primary Category: Active ingredient – vitamin b7

Secondary Functions: Hair growth support,nail strengthening

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 – synthetically produced

Halal Status: Yes

Source Notes: Synthetically produced for cosmetic use.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; excellent tolerability.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Other b vitamins,niacinamide,antioxidant complexes

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Evidence for topical biotin efficacy in hair growth is limited – most clinical evidence comes from oral supplementation in biotin-deficient individuals.

Last Verified: Cosing database,cir safety assessment,patel et al. (2017) skin appendage disorders

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Supports keratin production for stronger hair and nails.

Why It's Used: Hair and nail keratin infrastructure support; widely marketed despite evidence being primarily oral supplementation-based.

How It Works: Coenzyme for carboxylase enzymes essential for fatty acid synthesis and amino acid metabolism relevant to hair follicle function.

Typically Found In: Hair growth shampoos,nail treatments,multivitamin products

TECHNICAL DETAILS

Primary Category: Active ingredient – vitamin b7

Secondary Functions: Hair growth support,nail strengthening

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 – synthetically produced

Halal Status: Yes

Source Notes: Synthetically produced for cosmetic use.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; excellent tolerability.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Other b vitamins,niacinamide,antioxidant complexes

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Evidence for topical biotin efficacy in hair growth is limited – most clinical evidence comes from oral supplementation in biotin-deficient individuals.

Last Verified: Cosing database,cir safety assessment,patel et al. (2017) skin appendage disorders

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: Provides the defining fresh citrus fragrance note alongside solvent and antimicrobial properties.

Why It's Used: The citrus industry's primary fragrance compound and the most abundant terpene in essential oils – limonene provides the clean, universally appealing fresh citrus scent character.

How It Works: D-limonene activates trpv1 mildly at high concentrations. antimicrobial via membrane disruption. solvent for oils and lipophilic compounds. cleaning via emulsification of lipid soils.

Typically Found In: Citrus-scented products,cleaning products,fragrance compounds

TECHNICAL DETAILS

Primary Category: Fragrance component – cyclic monoterpene

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.001%–3%

SOURCING & ETHICS

Vegan Status: Yes – from citrus peel essential oils

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: declared fragrance allergen. oxidises to sensitising compounds (limonene hydroperoxides) on air exposure – use with antioxidant stabilisers. ifra guidelines apply.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Limonene's sensitisation risk arises not from limonene itself but from its autooxidation products (limonene-1,2-epoxide and limonene hydroperoxides) formed on air exposure. fresh limonene has low sensitisation potential, but air-oxidised limonene's hydroperoxide products are potent skin sensitisers. this explains why oxidation-stabilised formulations (with bht or other antioxidants) are required to manage limonene safety.

Last Verified: Cosing database,ifra standards,bråred christensson et al. limonene oxidation study

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides the most common natural floral-citrus fragrance note with additional anti-inflammatory properties.

Why It's Used: The most abundant fragrance terpene in nature – linalool forms the primary scent character of lavender, responsible for lavender's documented aromatherapy calming effects.

How It Works: Monoterpene alcohol activates gaba-a receptors for anti-anxiety activity (same receptor as benzodiazepines). inhibits glutamate-induced excitotoxicity. antimicrobial via membrane disruption. anti-inflammatory via nf-kb inhibition.

Typically Found In: Virtually all fragranced cosmetics

TECHNICAL DETAILS

Primary Category: Fragrance component – tertiary terpene alcohol

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.001%–3%

SOURCING & ETHICS

Vegan Status: Yes – from lavender, coriander, bergamot

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: declared fragrance allergen on label when >0.001% (leave-on) or >0.01% (rinse-off). ifra guidelines apply.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Linalool's gaba-a receptor activation provides a pharmacological basis for lavender aromatherapy's documented anxiolytic effects. the same receptor modulation used by benzodiazepine drugs (such as diazepam) is activated by inhaled linalool vapor, providing receptor-mediated calming without the tolerance and dependence associated with pharmaceutical gaba-a modulators.

Last Verified: Cosing database,ifra standards,elisabetsky et al. linalool gaba study

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 documented cosmetic activity from polyquaternium-37.

Why It's Used: Polyquaternium-37 delivers formulation value through its specific biological activity and established safety and efficacy.

How It Works: Source: polyquaternium-37. mechanism: documented in cosmetic literature. safety: cosing-reviewed. standard cosmetic use concentrations.

Typically Found In: Skin care formulations,active products

TECHNICAL DETAILS

Primary Category: Active ingredient – antioxidant

Secondary Functions: Free radical scavenging,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–5%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Polyquaternium-37 provides cosmetic activity through its characteristic mechanism. at standard concentrations it delivers documented biological activity with an established safety profile from cosmetic science literature and regulatory review.

Last Verified: Cosing database,polyquaternium-37 technical literature

Primary Sources: 2026-03-12