What Is Polyurethane-59?
Polyurethane-59 is a synthetic copolymer created from Ethylhexylglycerin, PEG-240, tetradecyloctadeceth-100 and hexamethylenediisocyanate. Each building block brings its own properties, and when they link together they form a flexible film-forming material that blends smoothly into water-based and oil-based systems. Members of the polyurethane family first showed up in industrial coatings during the 1940s, and formulators soon noticed their excellent stability and touch. Cosmetic chemists refined the chemistry to meet skin-care standards, arriving at versions like Polyurethane-59 that are both mild and high performing.
The polymer is produced through a controlled step-growth reaction that joins the diisocyanate with polyether and fatty alcohol units. The resulting resin is then neutralised, filtered and diluted into a liquid that disperses easily in standard manufacturing tanks. Thanks to this process the ingredient is consistent in molecular weight and purity, which helps brands keep batch-to-batch quality steady.
You will most often spot Polyurethane-59 in lotions, lightweight moisturizers, masks, primers, foundations, sunscreens, leave-on hair treatments and anti aging serums where a smooth feel and long-lasting texture are key selling points.
Polyurethane-59’s Cosmetic Benefits/Uses
Polyurethane-59 earns its place on an ingredient list by improving the way a formula looks, feels and stays mixed over time.
- Emulsion stabilising – keeps water and oil phases blended so the product stays uniform from the first pump to the last, preventing separation and extending shelf life
- Viscosity controlling – adjusts thickness, allowing formulators to create anything from a fluid serum to a rich cream while ensuring a smooth glide on skin
Who Can Use Polyurethane-59
Polyurethane-59 is considered suitable for most skin types including normal dry combination and oily because it forms a flexible breathable film that does not feel greasy or heavy. Its low irritation profile also makes it a good option for sensitive skin, though anyone with an impaired barrier or active dermatitis should introduce it slowly and watch for discomfort.
The polymer is fully synthetic and contains no animal derived materials so it is compatible with vegan and vegetarian lifestyles. Cruelty free status, however, depends on the finished brand and its testing policies.
Current safety data shows no specific concerns for women who are pregnant or breastfeeding because the large molecule sits on the surface of the skin and is not expected to penetrate. This is not medical advice and anyone who is expecting or nursing should clear new products with a doctor for extra peace of mind.
Polyurethane-59 does not absorb UV light or make skin more reactive to the sun so it is not linked to photosensitivity. It can even help sunscreen stay in place by improving film integrity.
Potential Side Effects/Adverse Reactions
Responses to topical Polyurethane-59 vary from person to person. The effects listed below are only possibilities and are unlikely to occur for the average user when the ingredient is included at the levels normally found in cosmetics.
- Mild skin irritation a brief stinging or burning sensation on very sensitive or compromised skin
- Contact dermatitis rare allergic reaction marked by redness itching or small bumps
- Eye irritation watering or discomfort if the product accidentally migrates into the eye area
If any irritation or allergy develops stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1 / 5
Polyurethane-59 molecules are large and sit on the surface of the skin, creating a breathable film rather than sinking into pores. The polymer itself is not oily and does not feed acne-causing bacteria, so the risk of clogging is minimal. This makes it generally suitable for people prone to breakouts. Keep in mind that the overall formula matters too; if a product pairs Polyurethane-59 with heavy oils the finished product could still be pore-clogging.
Summary
Polyurethane-59 stabilises emulsions and fine-tunes viscosity, helping creams, lotions, primers and sunscreens stay smooth and uniform while feeling light on the skin. Its popularity is moderate; formulators like the reliable performance yet it has not reached superstar status outside professional circles.
Current safety assessments place Polyurethane-59 in the low-risk category for irritation and sensitisation. As with any new cosmetic it is smart to do a quick patch test before full use, especially if you have sensitive or reactive skin.