What Is Polyurethane-7?
Polyurethane-7 is a man-made polymer created by linking together hexylene glycol, neopentyl glycol and adipic acid to form a soft polyester backbone, then reacting that backbone with isophorone diisocyanate and dimethylolpropanoic acid. The result is a water-dispersible polyurethane that dries into a clear flexible film. Polyurethanes were first developed in the 1930s for coatings and foams, but cosmetic chemists began adapting them in the 1990s when they noticed the polymers could give makeup and hair products better staying power without a stiff feel. Today the ingredient is produced in closed reactors under controlled heat where the starting glycols and acid are combined, followed by careful addition of the diisocyanate. After polymerization the mixture is neutralized, thinned with water and filtered to remove any impurities, yielding a smooth liquid that blends easily into cosmetic formulas. You will commonly find Polyurethane-7 in long-wear foundations, water-resistant sunscreens, liquid eyeliners, mascara, hair styling gels, nail polishes and skin serums that promise a smoothing or protective finish.
Polyurethane-7’s Cosmetic Benefits/Uses
Polyurethane-7 is classified as a film forming agent. It lays down a thin even layer on skin, hair or nails that locks pigments in place, boosts water resistance and helps the product stay put through sweat, humidity and light rubbing. This invisible film also smooths surface texture so makeup glides on more evenly and can reduce moisture loss by acting as a breathable barrier. The flexible nature of the polymer keeps the finish comfortable rather than tight or flaky, making it popular in long-wear cosmetics.
Who Can Use Polyurethane-7
Polyurethane-7 is gentle enough for most skin types. Oily and combination skin tend to like it because the flexible film helps makeup stay put without adding extra grease. Dry and normal skin benefit from the light barrier that slows moisture loss. Sensitive skin usually tolerates it as the large polymer molecules stay on the surface and do not sink in, though anyone who knows they react to synthetic films should be cautious.
The ingredient is made entirely from laboratory-produced raw materials so it contains no animal parts or by-products. That makes it suitable for both vegans and vegetarians as long as the rest of the formula is also free of animal ingredients.
Current safety data show no special warnings for pregnant or breastfeeding women because the polymer is too large to penetrate living skin. Still, this is not medical advice and pregnant or nursing users should run any skincare or makeup product past a doctor just to be safe.
Polyurethane-7 does not make skin more sensitive to sunlight, and it plays well with common actives such as vitamin C, retinoids and exfoliating acids. It also works under both physical and chemical sunscreens without breaking them down.
Potential Side Effects/Adverse Reactions
Responses to topical Polyurethane-7 vary from person to person. The effects listed below are possible but unlikely for most users when the ingredient is used at the low levels seen in cosmetics.
- Mild skin irritation or redness
- Contact dermatitis in people allergic to residual isocyanate traces
- Eye stinging if the product is accidentally rubbed into the eyes before it dries
- Rare clogged pores or breakouts in very acne-prone skin when used in heavy layers
- Build-up on hair strands leaving them dull if cleansing is insufficient
If any of these effects occur stop using the product and seek advice from a healthcare professional.
Comedogenic Rating
Rating: 1/5
Polyurethane-7 sits on the surface of skin as a lightweight breathable film, so it rarely traps enough oil or debris to block pores. It also carries no fatty acids or waxes that usually raise clogging risk. That said, layering very thick, heavy formulas that contain this polymer could create a temporary seal over congested areas and lead to the odd breakout in people who clog easily.
Overall Polyurethane-7 is considered suitable for acne-prone or breakout-prone skin, especially when used in sheer to moderate amounts.
Because it resists water and wear, double cleansing or using a dedicated makeup remover helps clear any residual film at night, further lowering the chance of build-up.
Summary
Polyurethane-7 is mainly valued for its film forming talent, creating an invisible flexible layer that locks makeup pigments in place, boosts water and sweat resistance, smooths texture and slows moisture loss without a stiff feel. These properties make it a go-to helper in long wear foundations, eyeliners, mascaras, sunscreens, hair gels and even some skin serums.
While not a buzzword ingredient consumers search for, formulators rely on it because it quietly improves performance and wear time. Safety studies rate it as low risk since its large molecules stay on the surface and cannot penetrate living skin, with irritation or allergy reports remaining rare.
Most people can use products containing Polyurethane-7 with confidence, but as with any new cosmetic it is wise to patch test first to make sure your skin agrees with the formula.