Ingredient review
PEG-100/IPDI Copolymer
INCI: PEG-100/IPDI Copolymer
A synthetic polymer that helps products stay put longer, especially in water-resistant formulas.
In plain English
This is a man-made ingredient that forms a thin, flexible film on your skin. It helps sunscreen, foundation, or other products resist water and sweat, so they don't slide off as easily. Think of it like a gentle, invisible shield that keeps your makeup or sun protection in place.
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
PEG-100/IPDI 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 PEG-100/IPDI 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 copolymer created by reacting polyethylene glycol (PEG-100) with isophorone diisocyanate (IPDI). It is a synthetic polymer designed to form a continuous film when applied to skin.
How it works
When applied, the copolymer molecules link together as the solvent evaporates, creating a uniform, flexible film. This film physically blocks water and oil from penetrating, enhancing the product's durability and water resistance.
Pros
Boosts water resistance
Helps sunscreens and makeup stay effective even when you sweat or get wet, so you don't have to reapply as often.
Improves wear time
Creates a flexible film that keeps foundation or tinted moisturizer in place for hours without creasing or fading.
Cons and cautions
Synthetic origin
Made from petrochemical-derived materials, which may be a concern for those seeking natural or 'clean' beauty products.
Potential tightness
In high concentrations, the film can feel slightly stiff or tight on skin, which some people find uncomfortable.
Best for
- People who want long-wearing or water-resistant makeup
- Those who use sunscreen and need it to stay effective during swimming or sweating
Use caution if
- Individuals with very dry or sensitive skin who may find film-formers uncomfortable
- Anyone avoiding all synthetic ingredients for personal reasons
Usage tips
Safety summary
PEG-100/IPDI Copolymer is considered safe for cosmetic use at typical concentrations. It is not significantly absorbed through skin and has low irritation and comedogenic potential. However, as with any film-former, some individuals may experience mild tightness or discomfort.
Research notes
Limited independent studies specifically on this copolymer, but it is structurally similar to other PEG-based film-formers that have a long history of safe use in cosmetics. The Cosmetic Ingredient Review (CIR) has evaluated related polymers and found them safe when formulated properly.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US, EU, and many other regions. No specific restrictions at typical use levels.
- Common uses
- Sunscreens, Water-resistant makeup, Long-wear foundations
- Environmental note
- As a synthetic polymer, it may not be biodegradable. Check product packaging for environmental claims.
Good to know
- This ingredient is commonly found in combination with other film-formers like acrylates copolymer.
- It is not absorbed into the skin; it stays on the surface to form its protective layer.
Common questions
What is PEG-100/IPDI Copolymer in beauty products?
This is a man-made ingredient that forms a thin, flexible film on your skin. It helps sunscreen, foundation, or other products resist water and sweat, so they don't slide off as easily. Think of it like a gentle, invisible shield that keeps your makeup or sun protection in place.
What does PEG-100/IPDI Copolymer do in a beauty product?
When applied, the copolymer molecules link together as the solvent evaporates, creating a uniform, flexible film. This film physically blocks water and oil from penetrating, enhancing the product's durability and water resistance.
Is PEG-100/IPDI Copolymer safe for most people?
PEG-100/IPDI Copolymer is considered safe for cosmetic use at typical concentrations. It is not significantly absorbed through skin and has low irritation and comedogenic potential. However, as with any film-former, some individuals may experience mild tightness or discomfort.
Who should be careful with PEG-100/IPDI Copolymer?
Individuals with very dry or sensitive skin who may find film-formers uncomfortable Anyone avoiding all synthetic ingredients for personal reasons
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.