What Is Polyurethane-97?
Polyurethane-97 is a synthetic film-forming polymer created when dimethyl carbonate reacts with hexanediol and isophorone diisocyanate. Chemists then “cap” the pre-polymer with a mix of hydroxyethyl, hydroxypropyl and hydroxybutyl acrylamides to give it the right balance of flexibility and durability for cosmetic use. The ingredient first appeared in color cosmetics in the late 1990s as brands looked for lightweight alternatives to older resins that could crack or yellow. Its ability to form clear, flexible films soon made it a staple in modern nail lacquers, top coats and base coats. You might also spot Polyurethane-97 in long-wear eye makeup, brow gels, glitter adhesives and peel-off facial masks where a strong yet comfortable film is essential.
Polyurethane-97’s Cosmetic Benefits/Uses
This ingredient earns its place in formulas for two main reasons
- Binding – Polyurethane-97 helps pigments, glitters and other particles stick together and stay put on the nail or skin. It forms a smooth film that resists water and everyday friction so color and shine last longer without flaking
- Nail conditioning – The flexible film can move with the nail plate which helps reduce chipping and splitting. By sealing in moisture it also leaves nails feeling less dry after polish removal
Who Can Use Polyurethane-97
Polyurethane-97 is considered gentle enough for most skin types including oily, dry and combination skin because it sits on the surface as a breathable film rather than soaking in deeply. Very sensitive or allergy-prone users should still check ingredient lists in case they react to any polyurethane or acrylamide derivatives.
The polymer is fully synthetic and contains no animal-derived raw materials so it is suitable for vegans and vegetarians. As always, cruelty-free status depends on the brand’s overall testing policy rather than the ingredient itself.
Current data shows no specific risks linked to topical use during pregnancy or while breastfeeding. This is not medical advice and anyone who is pregnant or nursing should run any new cosmetic product past a qualified doctor to be on the safe side.
Polyurethane-97 does not increase photosensitivity and will not make skin more likely to burn in sunlight. It is also fragrance-free and carries no known hormonal activity, making it a low-concern option for long-wear makeup and nail products.
Potential Side Effects/Adverse Reactions
Side effects from topical Polyurethane-97 vary from person to person. The points below list potential reactions that could occur in rare cases. When the ingredient is used correctly by the manufacturer most people will not experience any problems.
- Mild skin or nail irritation – a tight feeling, redness or itching can appear if the film traps moisture against very sensitive skin
- Allergic contact dermatitis – users already sensitized to polyurethane or acrylamide chemicals might develop a rash or swelling
- Eye irritation – if loose glitter or flakes carrying the polymer fall into the eye they can cause stinging or watering
- Nail brittleness – wearing thick polyurethane layers for extended periods without breaks can leave nails drier once polish is removed
- Interaction with strong solvents – acetone and similar removers can temporarily dehydrate the surrounding skin leading to peeling or white patches
If you notice any of these reactions stop using the product and seek advice from a healthcare professional.
Comedogenic Rating
Rating: 0 / 5
Polyurethane-97 is a high-molecular-weight polymer that forms an external film without seeping into pores. It contains no oils or fatty acids that would feed acne-causing bacteria and its slick surface actually repels excess sebum and debris rather than trapping them. Because of this it is considered non-comedogenic and is generally suitable for people who are prone to breakouts.
Since it stays on top of the skin, removal with a gentle cleanser is usually enough to prevent any build-up. Only in very rare cases where products are layered heavily for several days could residue mix with dead skin cells and contribute to congestion.
Summary
Polyurethane-97 acts as a binder and nail conditioner by laying down a clear flexible film that locks pigments glitter and moisture in place. The chemistry behind it lets the polymer bend with the nail or skin rather than crack, so manicures and long-wear makeup last longer and feel more comfortable.
While it is a staple in many modern nail lacquers top coats and some eye or brow formulas it is still less common than classic acrylates or silicone resins, largely because it costs more to produce and is tailored for performance products.
Current research shows Polyurethane-97 is low risk for irritation or systemic absorption when used as directed. As with any cosmetic ingredient it is smart to do a quick patch test when trying a new product to make sure your individual skin plays nicely with the formula.