Ingredient review
Dilinoleic Acid/Ethylenediamine Copolymer
INCI: DILINOLEIC ACID/ETHYLENEDIAMINE COPOLYMER
A synthetic polymer that helps products stay put and resist water, but offers no active skincare benefit.
In plain English
This is a man-made ingredient that forms a thin, flexible film on your skin or hair. It's like a clear, invisible shield that helps makeup or sunscreen stay in place longer and resist sweat or water. It doesn't moisturize or treat skin—it's purely a texture and performance helper.
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
Dilinoleic Acid/Ethylenediamine 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 Dilinoleic Acid/Ethylenediamine 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 dilinoleic acid (a fatty acid from plant oils) with ethylenediamine. The result is a large molecule that dries into a flexible film.
How it works
When applied, the copolymer molecules spread out and link together as the solvent evaporates, forming a continuous film. This film physically blocks water from reaching the underlying product and helps pigments or active ingredients adhere to the skin.
Pros
Boosts water resistance
Helps sunscreens and makeup stay effective even when you sweat or swim, so you don't have to reapply as often.
Improves wear time
Creates a flexible film that keeps foundation, mascara, or lip color from smudging or fading throughout the day.
Cons and cautions
Can feel heavy
In high concentrations, the film may feel tight or sticky on skin, which some people find uncomfortable.
Requires thorough removal
The water-resistant film doesn't wash off with water alone—you'll likely need an oil-based cleanser or micellar water to avoid residue.
Best for
- People who want long-wearing makeup or water-resistant sunscreen
- Those with normal to oily skin who don't mind a slight film feel
Use caution if
- People with very dry or sensitive skin who prefer lightweight, breathable formulas
- Anyone who dislikes the need for double cleansing to remove products
Usage tips
Safety summary
Generally considered safe for topical use. Low irritation and comedogenic risk. No known toxicity concerns at cosmetic concentrations. However, it offers no active benefit and may require extra effort to remove.
Research notes
Limited independent studies on this specific copolymer, but the broader class of polyamide film-formers has been reviewed by the CIR panel and deemed safe. Most evidence comes from manufacturer safety data rather than peer-reviewed clinical trials.
Common label clues
- Typical concentration
- 1% to 10%
- Regulatory status
- Approved for use in cosmetics in the EU, US, and many other regions. The Cosmetic Ingredient Review (CIR) panel has reviewed similar polyamide copolymers and found them safe at typical use concentrations.
- Common uses
- Sunscreens, Waterproof mascaras, Long-wear foundations, Lip products
- Environmental note
- As a synthetic polymer, it is not readily biodegradable. Some environmental groups raise concerns about its persistence in water systems, though it is used in small amounts.
Good to know
- This polymer is often listed as 'Polyamide-3' on some labels.
- It's considered safe by major regulatory bodies for use in cosmetics at typical levels.
- It's not biodegradable, so it may contribute to microplastic concerns in the environment.
Common questions
What is Dilinoleic Acid/Ethylenediamine Copolymer in beauty products?
This is a man-made ingredient that forms a thin, flexible film on your skin or hair. It's like a clear, invisible shield that helps makeup or sunscreen stay in place longer and resist sweat or water. It doesn't moisturize or treat skin—it's purely a texture and performance helper.
What does Dilinoleic Acid/Ethylenediamine Copolymer do in a beauty product?
When applied, the copolymer molecules spread out and link together as the solvent evaporates, forming a continuous film. This film physically blocks water from reaching the underlying product and helps pigments or active ingredients adhere to the skin.
Is Dilinoleic Acid/Ethylenediamine Copolymer safe for most people?
Generally considered safe for topical use. Low irritation and comedogenic risk. No known toxicity concerns at cosmetic concentrations. However, it offers no active benefit and may require extra effort to remove.
Who should be careful with Dilinoleic Acid/Ethylenediamine Copolymer?
People with very dry or sensitive skin who prefer lightweight, breathable formulas Anyone who dislikes the need for double cleansing to remove products
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.