Ingredient review
Polyurethane-73
INCI: Polyurethane-73
Polyurethane-73 is a synthetic film-former that helps products resist water and wear longer, but it offers no active skincare benefit.
In plain English
Polyurethane-73 is a plastic-like ingredient that dries into a thin, flexible film on your skin or hair. It's what makes some foundations last all day without smudging and mascaras resist tears and sweat. Think of it as a clear, invisible shield that helps your makeup stay put, but it doesn't moisturize or treat your skin.
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
Polyurethane-73 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 Polyurethane-73.
- 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
Polyurethane-73 is a synthetic polymer, a type of plastic, engineered specifically for cosmetics. It belongs to a family of polyurethanes that are valued for their flexibility and durability.
How it works
When applied, the water or solvent in the product evaporates, leaving behind a continuous, flexible film of Polyurethane-73. This film physically adheres to the skin or hair, creating a barrier that resists water, oil, and friction, thereby extending the wear of the product.
Pros
Excellent wear time
Creates a durable, water-resistant film that helps makeup last through sweat, tears, and humidity, reducing the need for touch-ups.
Flexible finish
Unlike some stiff polymers, Polyurethane-73 forms a flexible film that moves with your skin, reducing the chance of cracking or flaking throughout the day.
Cons and cautions
Can feel tight or dry
The film can create a slight tightening sensation on the skin, which may be uncomfortable for those with dry or sensitive skin types.
Requires thorough removal
Because it's water-resistant, Polyurethane-73 often requires an oil-based or dual-phase makeup remover to fully dissolve, adding an extra step to your routine.
Best for
- People who want long-wearing makeup that resists sweat and humidity
- Those who use waterproof mascara or long-stay foundation
Use caution if
- Individuals with very dry or dehydrated skin who prefer hydrating, breathable formulas
- Anyone who finds film-forming ingredients cause a tight or uncomfortable feeling
Usage tips
Safety summary
Polyurethane-73 is considered safe for use in cosmetics at typical concentrations. It has a low irritation and comedogenic risk, making it suitable for most skin types. However, it is a purely functional ingredient with no active skincare benefits.
Research notes
Research on Polyurethane-73 is limited to its function as a film-former. Cosmetic ingredient safety panels, such as the Cosmetic Ingredient Review (CIR), have evaluated similar polyurethane polymers and found them safe for use. No specific peer-reviewed studies on Polyurethane-73's efficacy or safety were identified.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US (FDA) and EU (CosIng). It is not a restricted ingredient and is considered safe at typical use concentrations.
- Common uses
- Long-wear foundations, Waterproof mascaras, Sunscreens, Hair styling products
- Environmental note
- As a synthetic polymer, Polyurethane-73 is not biodegradable. Its environmental impact is a consideration, though it is used in small amounts in rinse-off and leave-on products.
Good to know
- Polyurethane-73 is often used in 'transfer-proof' or '24-hour wear' makeup formulas.
- It is considered a safe, non-reactive ingredient for most skin types by cosmetic safety panels.
Common questions
What is Polyurethane-73 in beauty products?
Polyurethane-73 is a plastic-like ingredient that dries into a thin, flexible film on your skin or hair. It's what makes some foundations last all day without smudging and mascaras resist tears and sweat. Think of it as a clear, invisible shield that helps your makeup stay put, but it doesn't moisturize or treat your skin.
What does Polyurethane-73 do in a beauty product?
When applied, the water or solvent in the product evaporates, leaving behind a continuous, flexible film of Polyurethane-73. This film physically adheres to the skin or hair, creating a barrier that resists water, oil, and friction, thereby extending the wear of the product.
Is Polyurethane-73 safe for most people?
Polyurethane-73 is considered safe for use in cosmetics at typical concentrations. It has a low irritation and comedogenic risk, making it suitable for most skin types. However, it is a purely functional ingredient with no active skincare benefits.
Who should be careful with Polyurethane-73?
Individuals with very dry or dehydrated skin who prefer hydrating, breathable formulas Anyone who finds film-forming ingredients cause a tight or uncomfortable feeling
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.