What Is Polyurethane-72?
Polyurethane-72 is a man-made polymer created by reacting propanoic acid derivatives with a hydrogenated acetophenone-formaldehyde resin and a specialized di-isocyanate, then neutralizing part of the mix with 2-dimethylaminoethanol. The end result is a flexible yet durable resin that behaves like a tiny liquid plastic when dispersed in water or solvent. Polyurethanes first showed up in the 1930s as substitutes for natural rubber, and cosmetic chemists began adapting them in the late 20th century for their film-forming talent. Today’s version, Polyurethane-72, was engineered to deliver a clear, breathable film that holds colorants and actives in place without feeling stiff or heavy.
The production process starts with carefully measured monomers blended under controlled heat and vacuum to build long chains, followed by a curing step that locks those chains into a stable network. The finished polymer is then ground or emulsified into a fine dispersion that can be mixed into cosmetic bases.
You will most often find Polyurethane-72 in nail polishes, lash and brow gels, liquid eyeliners, long-wear foundations, transfer-resistant lip colors and flexible hair styling products. Its strong yet lightweight film also makes it useful in certain facial masks and skin-tightening primers where a smooth, even finish is desired.
Polyurethane-72’s Cosmetic Benefits/Uses
Formulators choose Polyurethane-72 because it brings several performance boosts to beauty products
- Binding – Acts as a glue that holds pigment particles and other ingredients together so the formula stays homogenous and color payoff remains consistent during wear
- Film Forming – Spreads into a thin, uniform layer that dries to a flexible film, helping makeup resist smudging, flaking and water while still allowing skin or nails to breathe
- Nail Conditioning – Adds a protective coating that can reinforce the nail surface, reduce chipping and enhance shine giving manicures a longer-lasting salon look
Who Can Use Polyurethane-72
Because Polyurethane-72 is an inert synthetic resin, it generally plays well with all skin types including oily, dry, combination and mature skin. Its breathable film does not seal pores so it rarely aggravates acne prone complexions. Those with very reactive or allergy prone skin should still keep an eye on products containing multiple film formers, as complex formulas can occasionally trigger irritation in a small subset of users.
The ingredient is created entirely from petrochemical feedstocks and laboratory reagents, not from animals, so it is suitable for both vegans and vegetarians. Finished products may still contain animal derived pigments or waxes, so label checking is advised.
Current safety data show no evidence that Polyurethane-72 is absorbed through intact skin or nails in amounts that would pose a risk to pregnant or breastfeeding women. That said this commentary is informational only. Expectant or nursing mothers should review any cosmetic routine with their healthcare provider to be certain it aligns with personal medical advice.
Polyurethane-72 does not react with ultraviolet light and has not been linked to photosensitivity. It also does not interfere with self tanners or sun protection actives. No other special usage restrictions are noted for healthy individuals.
Potential Side Effects/Adverse Reactions
Responses to topical Polyurethane-72 vary from person to person. The issues below are possible but uncommon assuming the finished product is formulated and preserved correctly.
- Mild skin or nail irritation – Redness itching or a tight feeling can occur in users who are sensitive to resin based film formers
- Allergic contact dermatitis – Very rare cases of allergic rash have been reported with polyurethane resins particularly in people already sensitized to isocyanate chemistry
- Eye stinging or watering – If a product containing the polymer migrates into the eye it may cause temporary discomfort until rinsed away
- Nail plate discoloration – Extended wear of heavily pigmented polish films can sometimes leave a slight stain on the nail surface though this is usually due to the colorants not the polymer itself
If any persistent burning swelling or rash develops discontinue use immediately and seek medical advice
Comedogenic Rating
Rating: 1/5 – Polyurethane-72 is a large, inert polymer that sits on the surface of skin or nails and does not provide an oily or waxy residue that could clog pores. Its breathable film lets sebum escape instead of trapping it, so the likelihood of blocked pores is extremely low. Because the polymer is usually present at modest levels in finished formulas and is not occlusive, it earns a near-non-comedogenic score.
Suitable for acne-prone or breakout-prone users in most cases.
Only when the polymer is combined with heavy oils or butters in a product could pore congestion become a concern, so always consider the entire ingredient list rather than one component in isolation.
Summary
Polyurethane-72 acts as a binder, film former and nail conditioner. It glues pigments together, spreads into a thin flexible layer that resists smudging and water, and adds a protective shine to nails which helps reduce chipping. These benefits come from its long polymer chains that lock into place as they dry, forming a clear durable mesh.
While not as famous as silicones or acrylics, this polyurethane quietly underpins many long-wear eye, lip, nail and complexion products found on today’s shelves because it delivers staying power without a heavy feel.
Safety studies find minimal absorption through intact skin or nails and irritation cases are rare. Still, everyone’s skin is different so it is wise to patch test any new product containing Polyurethane-72 before regular use.