Ingredient review

Ethylenediamine/Stearyl Dimer Dilinoleate Copolymer

INCI: ETHYLENEDIAMINE/STEARYL DIMER DILINOLEATE COPOLYMER

A synthetic film-former that helps products stay put and resist water, but offers no active skincare benefit.

beautyskincarefilm-former

In plain English

This ingredient is a plastic-like polymer that spreads into a thin, flexible film when applied to skin or hair. It helps makeup and sunscreen stay in place longer and resist sweat or water. Think of it like an invisible, breathable wrap that holds the product where you put it.

Review score

Safety, usefulness, and evidence

3.8Good
3.8/ 5

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
How reviews are scored

Quick decision guide

Useful, but context matters

Ethylenediamine/Stearyl Dimer Dilinoleate 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.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Ethylenediamine/Stearyl Dimer Dilinoleate Copolymer.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. 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

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

A synthetic copolymer created by reacting ethylenediamine with a modified fatty acid (stearyl dimer dilinoleate). It belongs to a class of ingredients called film-formers, which are long-chain molecules that can form a continuous layer when the solvent (water or oil) evaporates.

How it works

When the product is applied, the solvent evaporates and the copolymer molecules link together into a thin, flexible film. This film physically locks in other ingredients (like sunscreen filters or pigments) and creates a barrier that resists water, sweat, and rubbing. It also adds a slight thickening effect to the product's texture.

Pros

Boosts wear time

Creates a flexible film that helps makeup and sunscreen stay put for hours, even in humid or sweaty conditions.

Water-resistant barrier

Forms a protective layer that resists water and sweat, making it ideal for swim-proof sunscreens and long-wear mascaras.

Cons and cautions

Can feel tight or dry

On sensitive or dry skin, the film may create a slight tightening sensation or emphasize dry patches.

Requires double cleansing

Because it forms a water-resistant film, it often needs an oil-based cleanser or micellar water for thorough removal.

Best for

  • People who want long-wearing, water-resistant makeup or sunscreen
  • Those with normal to oily skin who don't mind a slight film feel

Use caution if

  • Individuals with very dry or compromised skin barriers who may find film-formers uncomfortable
  • Anyone who prefers minimal, easily removable products

Usage tips

Use an oil-based cleanser or micellar water to fully remove products containing this ingredient.
If you have dry skin, apply a moisturizer underneath products with this film-former to avoid a tight feeling.
Layer it only where you need extra hold or water resistance — avoid applying all over if your skin is prone to congestion.

Safety summary

Generally recognized as safe for topical use at typical concentrations. Low irritation and comedogenic potential. No significant safety concerns reported in cosmetic use.

Research notes

Limited independent research on this specific copolymer. Safety is inferred from its chemical class and long history of use in cosmetics. No published studies on skin penetration or systemic absorption.

Common label clues

Typical concentration
0.5% to 5%
Regulatory status
Approved for use in cosmetics in the EU, US, and other major markets. No specific restrictions beyond general cosmetic safety requirements.
Common uses
Sunscreens, Waterproof mascaras, Long-wear foundations, Hair styling products
Environmental note
As a synthetic polymer, it is not biodegradable. However, it is used at low levels and is not considered a major environmental concern compared to microplastics.

Good to know

  • This ingredient is not a humectant, emollient, or active — it's purely a functional polymer for texture and wear.
  • It is often combined with other film-formers to fine-tune flexibility and water resistance.
  • On ingredient labels, it may appear near the end of the list because it's used at low concentrations.

Common questions

What is Ethylenediamine/Stearyl Dimer Dilinoleate Copolymer in beauty products?

This ingredient is a plastic-like polymer that spreads into a thin, flexible film when applied to skin or hair. It helps makeup and sunscreen stay in place longer and resist sweat or water. Think of it like an invisible, breathable wrap that holds the product where you put it.

What does Ethylenediamine/Stearyl Dimer Dilinoleate Copolymer do in a beauty product?

When the product is applied, the solvent evaporates and the copolymer molecules link together into a thin, flexible film. This film physically locks in other ingredients (like sunscreen filters or pigments) and creates a barrier that resists water, sweat, and rubbing. It also adds a slight thickening effect to the product's texture.

Is Ethylenediamine/Stearyl Dimer Dilinoleate Copolymer safe for most people?

Generally recognized as safe for topical use at typical concentrations. Low irritation and comedogenic potential. No significant safety concerns reported in cosmetic use.

Who should be careful with Ethylenediamine/Stearyl Dimer Dilinoleate Copolymer?

Individuals with very dry or compromised skin barriers who may find film-formers uncomfortable Anyone who prefers minimal, easily removable products

Research sources

CosIng (EU Cosmetic Ingredient Database)OpenPersonal Care Council (INCI Directory)OpenPubMed - Polymer film-formers in cosmeticsOpen

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.