What Is Polyurethane-75?
Polyurethane-75 is a synthetic copolymer created through a controlled reaction of toluene diisocyanate, Bisphenol A bis-(2-hydroxypropyl) ether, and poly(1,4-butanediol)-28, followed by a final capping step with 2-hydroxypropyl methacrylate. The resulting network links hard aromatic units with flexible aliphatic segments, giving the material a balanced mix of strength and pliability. First explored by industrial chemists for coatings and adhesives, this specific grade was refined in the late 1990s so it could disperse smoothly in water and remain stable in the presence of cosmetic actives. Its adoption by formulators grew as demand rose for lightweight films that enhance product texture without leaving a heavy residue. Today you will most commonly see Polyurethane-75 in rinse-off masks, long-wear foundations, setting sprays, waterproof mascaras, hair styling creams, and transfer-resistant lip products, where it helps hold the formula together and improve application.
Polyurethane-75’s Cosmetic Benefits/Uses
Polyurethane-75 offers a single, yet highly valuable, function in cosmetic science: binding. By acting as a binder it keeps pigments, powders, and other ingredients evenly suspended, preventing separation during storage and ensuring a smooth, uniform layer when the product is applied. This translates to makeup that wears longer without cracking or flaking, hair products that distribute evenly from root to tip, and skincare masks that maintain their integrity until rinsed away.
Who Can Use Polyurethane-75
Because Polyurethane-75 is an inert film-forming binder it is generally suitable for dry, normal and oily skin types alike. Its lightweight texture does not add extra oil so it typically works fine for acne-prone skin, while its flexible film helps limit moisture loss which can benefit drier complexions. There is no evidence that it aggravates sensitive skin, though anyone with a known allergy to polyurethane materials should exercise caution.
The ingredient is created entirely through synthetic chemistry with no animal-derived inputs, making it acceptable for both vegetarians and vegans.
No studies have shown Polyurethane-75 to pose a specific risk during pregnancy or while breastfeeding. Although absorption through intact skin is expected to be negligible, this is not medical advice and anyone who is pregnant or nursing should review any product containing the ingredient with a healthcare provider.
Polyurethane-75 does not increase photosensitivity, nor does it interfere with sunscreen actives. It is fragrance-free and colorless so it is unlikely to cause staining or odor issues in finished products.
Potential Side Effects/Adverse Reactions
Reactions to topical Polyurethane-75 vary from person to person. The following list covers potential side effects, but they are uncommon when the ingredient is properly formulated and used.
- Contact irritation – rare instances of redness, itching or mild burning have been reported in people with very reactive skin
- Allergic contact dermatitis – individuals already sensitized to urethane compounds could develop localized rash or swelling
- Eye stinging – if a product containing Polyurethane-75 accidentally gets into the eyes it may cause temporary discomfort or watering
- Occlusive buildup – heavy layering in leave-on products might trap sweat and sebum leading to clogged pores in some users
If any of these effects occur stop using the product and consult a qualified healthcare professional.
Comedogenic Rating
Rating: 1/5. Polyurethane-75 has a very large molecular size and contains no oily or waxy fractions, so it tends to sit on the surface rather than seeping into pores. The lightweight film it forms is breathable for most skin types, minimising the chance of trapped sebum. For this reason it is generally considered suitable for people prone to acne or breakouts. Only in very dense leave-on formulas or when layered with rich occlusives could it potentially contribute to pore congestion.
Summary
Polyurethane-75 acts mainly as a binder and film former, locking pigments and other particles into a uniform suspension so the finished product applies evenly and stays put. Its balanced mix of rigid and flexible segments lets it create a thin resilient film that resists cracking yet feels light on skin and hair.
While not as famous as silicones or acrylics, this polymer has carved out a steady spot in long-wear makeup, waterproof mascara, setting sprays and certain hair stylers where dependable binding is key. Safety data show a low risk of irritation or sensitisation and it scores almost zero for comedogenicity, making it well tolerated across skin types. As with any new cosmetic ingredient it is wise to patch test a product before full use just to make sure your skin agrees with it.