Ingredient review
Quaternium-90 Montmorillonite
INCI: Quaternium-90 Montmorillonite
A modified clay that helps control oil and improve product feel, generally safe but not well-studied in long-term use.
In plain English
Quaternium-90 Montmorillonite is a clay that has been chemically modified to make it more compatible with skin and hair. In simple terms, it's a special type of clay that can absorb excess oil and help products feel smoother. You'll often find it in face masks, shampoos, and creams where it helps control shine and improve texture without feeling heavy.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Quaternium-90 Montmorillonite is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Quaternium-90 Montmorillonite.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A quaternized (positively charged) derivative of montmorillonite clay, created by reacting natural clay with quaternary ammonium compounds. This modification makes the clay more dispersible in water and gives it antistatic and conditioning properties.
How it works
In a cosmetic product, Quaternium-90 Montmorillonite works by absorbing excess sebum and moisture from the skin or hair surface. Its positive charge helps it bind to negatively charged surfaces like hair and skin, providing a smooth, non-greasy feel and reducing static electricity in hair.
Pros
Effective oil control
Absorbs excess sebum without leaving a heavy residue, making it ideal for oily skin types and shine-prone areas.
Improves product feel
Creates a silky, smooth texture in creams and masks, enhancing the sensory experience during application.
Cons and cautions
Limited safety research
There is not a large body of peer-reviewed studies on long-term use of this modified clay, so its full safety profile is less established than simpler clays.
Potential for dryness
Because it absorbs moisture, it may over-dry already dry or sensitive skin if used too frequently or in high concentrations.
Best for
- People with oily or combination skin looking for shine control
- Those who want a smoother, less greasy feel in their skincare or haircare products
Use caution if
- Individuals with very dry or dehydrated skin, as it may absorb too much moisture
Usage tips
Safety summary
Generally considered safe for topical use in cosmetics at typical concentrations. However, long-term safety data is limited, and individuals with very dry or sensitive skin should use with caution.
Research notes
Most evidence comes from formulation studies and general knowledge of clay and quaternary ammonium compounds. Direct clinical studies on Quaternium-90 Montmorillonite are scarce.
Common label clues
- Typical concentration
- 0.1% to 5%
- Regulatory status
- Approved for use in cosmetics in the EU, US, and many other regions. No specific restrictions beyond general cosmetic safety requirements.
- Common uses
- Face masks, Shampoos, Conditioners, Creams
- Environmental note
- Montmorillonite is a naturally occurring clay, but the quaternization process involves synthetic chemicals. Its environmental impact is not well-documented.
Good to know
- This ingredient is often listed near the end of ingredient lists because it is used in small amounts.
- It is a modified clay, so it may not be suitable for 'natural' or 'clean' beauty formulations.
Common questions
What is Quaternium-90 Montmorillonite in beauty products?
Quaternium-90 Montmorillonite is a clay that has been chemically modified to make it more compatible with skin and hair. In simple terms, it's a special type of clay that can absorb excess oil and help products feel smoother. You'll often find it in face masks, shampoos, and creams where it helps control shine and improve texture without feeling heavy.
What does Quaternium-90 Montmorillonite do in a beauty product?
In a cosmetic product, Quaternium-90 Montmorillonite works by absorbing excess sebum and moisture from the skin or hair surface. Its positive charge helps it bind to negatively charged surfaces like hair and skin, providing a smooth, non-greasy feel and reducing static electricity in hair.
Is Quaternium-90 Montmorillonite safe for most people?
Generally considered safe for topical use in cosmetics at typical concentrations. However, long-term safety data is limited, and individuals with very dry or sensitive skin should use with caution.
Who should be careful with Quaternium-90 Montmorillonite?
Individuals with very dry or dehydrated skin, as it may absorb too much moisture
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.