Ingredient review
Phthalic Anhydride/Benzoic Acid/Glycerin Copolymer
INCI: PHTHALIC ANHYDRIDE/BENZOIC ACID/GLYCERIN COPOLYMER
A synthetic film-former that helps products stay put and resist water, but offers no active skincare benefit.
In plain English
This is a man-made polymer that dries down to form a thin, flexible film on your skin or hair. Think of it like a clear, invisible raincoat that helps makeup last longer or keeps sunscreen from washing off. It doesn't moisturize or treat your skin—it's purely a performance ingredient.
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
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Phthalic Anhydride/Benzoic Acid/Glycerin Copolymer 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 Phthalic Anhydride/Benzoic Acid/Glycerin Copolymer.
- 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 synthetic copolymer created by reacting phthalic anhydride, benzoic acid, and glycerin. It belongs to a class of ingredients called polyesters and is designed to form a continuous film when applied to the skin or hair.
How it works
When the product dries, the polymer molecules link together into a flexible, water-resistant layer. This film physically blocks water and sweat from disturbing the product underneath, while also helping other ingredients (like pigments or UV filters) stay evenly distributed.
Pros
Boosts water resistance
Helps sunscreens and makeup stay effective even when you sweat or swim, reducing the need for frequent reapplication.
Improves wear time
Creates a flexible film that keeps foundation, eyeliner, or lip color in place for hours without cracking or fading.
Cons and cautions
No skincare benefit
Unlike humectants or antioxidants, this ingredient does nothing to hydrate, soothe, or protect your skin—it's purely a cosmetic enhancer.
Can be hard to remove
The water-resistant film may require an oil-based cleanser or double cleansing to fully remove, which can be inconvenient.
Best for
- People who want long-wearing or waterproof makeup
- Those using water-resistant sunscreens for swimming or sweating
Use caution if
- Anyone with very dry or sensitive skin who prefers lightweight, breathable formulas
Usage tips
Safety summary
Generally considered safe for topical use at typical concentrations. The polymer is too large to penetrate the skin, so it stays on the surface. No significant irritation or allergy concerns have been reported in cosmetic use.
Research notes
Limited independent research on this specific copolymer, but film-forming polymers as a class are well-studied for cosmetic safety. The main evidence comes from manufacturer safety data and regulatory reviews.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the EU, US, and many other regions. The Cosmetic Ingredient Review (CIR) panel has reviewed similar polyester film-formers and found them safe at typical use levels.
- Common uses
- Sunscreens, Waterproof makeup, Hair styling products, Long-wear foundations
- Environmental note
- As a synthetic polymer, it is not biodegradable and may contribute to microplastic pollution. Some brands are moving toward biodegradable alternatives.
Good to know
- This ingredient is often listed under the trade name 'Polyester-1' in some formulations.
- It is not related to harmful phthalates—the name refers to the chemical building block phthalic anhydride, which is fully reacted into a safe polymer.
Common questions
What is Phthalic Anhydride/Benzoic Acid/Glycerin Copolymer in beauty products?
This is a man-made polymer that dries down to form a thin, flexible film on your skin or hair. Think of it like a clear, invisible raincoat that helps makeup last longer or keeps sunscreen from washing off. It doesn't moisturize or treat your skin—it's purely a performance ingredient.
What does Phthalic Anhydride/Benzoic Acid/Glycerin Copolymer do in a beauty product?
When the product dries, the polymer molecules link together into a flexible, water-resistant layer. This film physically blocks water and sweat from disturbing the product underneath, while also helping other ingredients (like pigments or UV filters) stay evenly distributed.
Is Phthalic Anhydride/Benzoic Acid/Glycerin Copolymer safe for most people?
Generally considered safe for topical use at typical concentrations. The polymer is too large to penetrate the skin, so it stays on the surface. No significant irritation or allergy concerns have been reported in cosmetic use.
Who should be careful with Phthalic Anhydride/Benzoic Acid/Glycerin Copolymer?
Anyone with very dry or sensitive skin who prefers lightweight, breathable formulas
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.