Ingredient review

Polyurea Crosspolymer-4

INCI: Polyurea Crosspolymer-4

A synthetic polymer that helps products spread smoothly and stay put, with a low risk of irritation.

beautyskincarefilm-former

In plain English

Polyurea Crosspolymer-4 is a man-made ingredient that forms a thin, flexible film on the skin. This film helps makeup and skincare products glide on evenly, feel silky, and last longer without smudging or fading. Think of it as a gentle, invisible net that holds everything in place.

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

Polyurea Crosspolymer-4 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 Polyurea Crosspolymer-4.
  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 crosslinked polymer belonging to the polyurea family, designed to create a flexible film on the skin.

How it works

When applied, the polymer molecules link together to form a continuous, breathable film. This film improves the spreadability of the product, reduces transfer (like from face to mask or clothing), and helps other ingredients stay on the skin longer.

Pros

Improves wear time

Helps makeup and sunscreen stay in place longer, reducing the need for touch-ups throughout the day.

Silky texture

Gives products a smooth, non-greasy feel that glides onto the skin without pilling.

Cons and cautions

Synthetic origin

Made from man-made materials, which may not align with natural or minimalist skincare preferences.

Limited long-term data

While generally considered safe, there is less independent research on this specific polymer compared to older ingredients.

Best for

  • Anyone wanting long-lasting makeup or sunscreen
  • People with normal to combination skin

Use caution if

  • Those who strictly avoid synthetic ingredients

Usage tips

Apply over moisturizer for best adhesion and even spread.
Use with powder products to lock in a matte finish.

Safety summary

Polyurea Crosspolymer-4 is considered safe for topical use at typical concentrations. It has low irritation and comedogenic potential. No significant safety concerns have been reported in cosmetic use.

Research notes

Research on this specific polymer is limited, but it is structurally similar to other well-studied film-forming polymers used in cosmetics. Safety assessments by industry panels support its use.

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 known.
Common uses
Foundations, Primers, Sunscreens, Long-wear makeup
Environmental note
As a synthetic polymer, its biodegradability is limited. However, it is used in small amounts and is not known to bioaccumulate.

Good to know

  • Polyurea Crosspolymer-4 is often used in combination with silicones for a velvety feel.
  • It is considered non-comedogenic and unlikely to clog pores.

Common questions

What is Polyurea Crosspolymer-4 in beauty products?

Polyurea Crosspolymer-4 is a man-made ingredient that forms a thin, flexible film on the skin. This film helps makeup and skincare products glide on evenly, feel silky, and last longer without smudging or fading. Think of it as a gentle, invisible net that holds everything in place.

What does Polyurea Crosspolymer-4 do in a beauty product?

When applied, the polymer molecules link together to form a continuous, breathable film. This film improves the spreadability of the product, reduces transfer (like from face to mask or clothing), and helps other ingredients stay on the skin longer.

Is Polyurea Crosspolymer-4 safe for most people?

Polyurea Crosspolymer-4 is considered safe for topical use at typical concentrations. It has low irritation and comedogenic potential. No significant safety concerns have been reported in cosmetic use.

Who should be careful with Polyurea Crosspolymer-4?

Those who strictly avoid synthetic ingredients

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.