What Is Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer?
Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer is a lab made plastic-like ingredient created by linking together small units of 1,4-butanediol and isophorone diisocyanate, then finishing the chain with hydroxyethyl methacrylate. The result is a lightweight flexible polymer that behaves a bit like a liquid glue when added to creams or gels. It was first explored by chemists looking for gentler alternatives to the stiff resins used in hair sprays and nail lacquers of the 1980s. As testing showed it could hold pigments and skincare actives in place without making the formula feel heavy it found its way into modern cosmetics.
Production starts with 1,4-butanediol, a common building block sourced from petroleum or corn sugar. This reacts with isophorone diisocyanate under controlled heat to build a backbone of repeating units. Hydroxyethyl methacrylate is then attached to the ends so the finished polymer can mix easily with water or oil. Quality checks confirm consistent chain length, listed as “22” in the name.
You will most often spot this ingredient in long-wear makeup like liquid foundations, waterproof mascaras and stay-put lip colors. It is also used in gel face masks, peel-off treatments and some lightweight moisturizers where formulators need a clear flexible film to keep the product evenly spread on skin.
Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer’s Cosmetic Benefits/Uses
The main job of this polymer is binding which gives several practical perks inside a cosmetic formula. By grabbing onto pigments, shimmer and skincare actives it keeps them evenly mixed so you get the same dose with every swipe or pump. The ingredient also helps the finished product stick to skin or lashes longer resisting sweat and light rubbing while staying comfortable and breathable.
Who Can Use Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer
This film-forming polymer is light enough for oily and combination skin yet flexible enough not to accentuate dry patches, making it broadly suitable for most skin types. Extremely sensitive or allergy-prone users who react to acrylics should approach with caution because the ingredient falls within the methacrylate family and could trigger redness or itching in that subset.
The material is fully synthetic and contains no animal by-products, so products relying on it as the main binder are usually compatible with vegan and vegetarian lifestyles unless other formula components say otherwise.
Because the molecule is large and sits on the surface rather than sinking into deeper layers, there is no evidence of risk to pregnant or breastfeeding women when used topically. Still, this is not medical advice and anyone who is expecting or nursing should run all skincare choices past a qualified doctor to stay on the safe side.
Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer does not absorb UV light and is not known to cause photosensitivity, so it will not make skin more vulnerable to sunburn. Always follow standard sun protection practices when outdoors.
Potential Side Effects/Adverse Reactions
Reactions to topical Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer vary from person to person. The points below highlight potential side effects, though they are uncommon when the ingredient is used correctly in a finished cosmetic.
- Mild skin irritation – slight redness or stinging can appear on very sensitive skin, especially around eyes or broken areas
- Allergic contact dermatitis – rare but possible in individuals already allergic to acrylates or isocyanate-derived compounds
- Eye irritation – if mascara or eyeliner formulas containing the polymer flake into the eye it may cause temporary watering or discomfort
- Clogged pores for acne-prone users – the flexible film can trap sweat and sebum under heavy makeup layers, leading to the occasional breakout
- Incompatibility with certain actives – very high concentrations of strong solvents or acids can destabilize the polymer film, potentially increasing irritation
If you notice persistent discomfort, swelling or rash while using a product that contains this ingredient stop use immediately and seek advice from a healthcare professional.
Comedogenic Rating
Rating: 1/5
Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer is a large water-dispersible molecule that sits on top of skin rather than soaking into pores, so by itself it has very low clogging potential. It is not oily and does not feed acne-causing bacteria, which keeps its score near zero. The rating climbs to a 1 only because the flexible film it forms can trap sweat and sebum if the finished product is applied in thick layers or combined with heavier waxes and silicones.
Most people prone to breakouts can use products containing this polymer without issues, provided the rest of the formula is lightweight and removed thoroughly at the end of the day.
If the ingredient is paired with highly occlusive agents such as mineral oil or petrolatum the overall product could feel heavier and raise the risk of congestion, so always look at the full ingredient list.
Summary
Bis-Hema Poly(1,4-Butanediol)-22/Ipdi Copolymer acts mainly as a binder and film former. Its long flexible chains grab onto pigments and skincare actives, keep them evenly suspended then dry into a clear breathable layer that helps makeup or treatment masks stay put. This improves wear time, color payoff and even delivery of active ingredients without adding weight.
The polymer is a niche pick rather than a mainstream star, showing up mostly in long-wear foundations, waterproof eye products and some peel-off masks where formulators need dependable but comfortable hold.
Safety data classifies it as low risk for irritation or sensitization, and it is non-toxic when used topically. While most users tolerate it well, everyone’s skin is different so it is smart to patch test any new product containing this ingredient before full-face use.