Ingredient review

Dimer Dilinoleic Acid Copolymer

INCI: DIETHYLENE GLYCOL/HYDROGENATED DIMER DILINOLEIC ACID COPOLYMER

A safe, synthetic film-former that helps products stay put and resist water without clogging pores.

beautyskincarefilm-former

In plain English

This ingredient is a type of plastic-like polymer that forms a thin, flexible film on your skin or hair. It's often added to sunscreens and long-wear makeup to make them water-resistant and help them last longer. Think of it as a clear, invisible shield that keeps the product in place without feeling heavy or sticky.

Review score

Safety, usefulness, and evidence

4.0Good
4.0/ 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

Dimer Dilinoleic Acid 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 Dimer Dilinoleic Acid 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 diethylene glycol with hydrogenated dimer dilinoleic acid. It belongs to a family of ingredients known as film-formers, which are used to create a continuous layer on the skin.

How it works

When applied, the polymer molecules link together to form a thin, flexible film. This film helps other ingredients (like sunscreen filters or pigments) stay evenly distributed and resist being washed off by water or sweat. It also adds a smooth, silky feel to the product.

Pros

Boosts water resistance

Helps sunscreens and makeup stay effective even when you sweat or swim, reducing the need for frequent reapplication.

Lightweight feel

Unlike some older film-formers, this copolymer dries down to a flexible, non-tacky finish that doesn't feel heavy or sticky.

Cons and cautions

Synthetic origin

It is a man-made polymer, which may be a concern for those seeking fully natural or biodegradable formulations.

Potential tightness

On very dry or sensitive skin, the film can sometimes feel slightly tight or uncomfortable, especially if layered with other occlusive ingredients.

Best for

  • Anyone wanting longer-lasting sunscreen or makeup
  • People with oily skin who prefer matte, transfer-resistant products

Use caution if

  • Those with extremely dry or compromised skin barriers who may find film-formers too occlusive

Usage tips

Apply to damp skin for a more even film
Layer with water-based products first to avoid pilling
Use a gentle oil-based cleanser to remove products containing this polymer

Safety summary

Considered safe for cosmetic use at typical concentrations. Low irritation and comedogenic potential. No significant safety concerns reported in regulatory reviews.

Research notes

Limited independent studies, but regulatory bodies (FDA, EU SCCS) have reviewed similar film-forming polymers and found them safe. The ingredient is well-established in commercial formulations.

Common label clues

Typical concentration
1% to 10%
Regulatory status
Approved for use in cosmetics globally, including by the U.S. FDA and EU CosIng database, with no known restrictions at typical use levels.
Common uses
Sunscreens, Waterproof makeup, Long-wear foundations, Lip products
Environmental note
As a synthetic polymer, it is not biodegradable. However, it is not classified as a microplastic and is used in low concentrations.

Good to know

  • Often used in combination with other film-formers to fine-tune texture and durability
  • Commonly found in 'sport' or 'active' sunscreen formulas

Common questions

What is Dimer Dilinoleic Acid Copolymer in beauty products?

This ingredient is a type of plastic-like polymer that forms a thin, flexible film on your skin or hair. It's often added to sunscreens and long-wear makeup to make them water-resistant and help them last longer. Think of it as a clear, invisible shield that keeps the product in place without feeling heavy or sticky.

What does Dimer Dilinoleic Acid Copolymer do in a beauty product?

When applied, the polymer molecules link together to form a thin, flexible film. This film helps other ingredients (like sunscreen filters or pigments) stay evenly distributed and resist being washed off by water or sweat. It also adds a smooth, silky feel to the product.

Is Dimer Dilinoleic Acid Copolymer safe for most people?

Considered safe for cosmetic use at typical concentrations. Low irritation and comedogenic potential. No significant safety concerns reported in regulatory reviews.

Who should be careful with Dimer Dilinoleic Acid Copolymer?

Those with extremely dry or compromised skin barriers who may find film-formers too occlusive

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.