What Is Polyurea Crosspolymer-1?
Polyurea Crosspolymer-1 is a man-made powder created when four different isocyanates react with a branched polymer called PEI-45. The isocyanates involved are a trimer of hexamethylene diisocyanate, saturated methylene diphenyldiisocyanate, the monourea of the hexamethylene diisocyanate trimer joined with ammonium cyclohexylaminopropanesulfonate, and straight hexamethylene diisocyanate. When these ingredients link together they form a tight three-dimensional network, giving the final material its “crosspolymer” name.
The technology behind polyurea powders first showed up in industrial coatings where toughness and oil-absorption were prized. Formulators later saw that the same oil-grabbing quality could help make cosmetics feel lighter and stay shine-free. Over the past decade suppliers refined particle size and purity so the ingredient could meet safety rules for skin care.
Production starts with carefully measured liquid isocyanates that react with PEI-45 under controlled heat. The mixture thickens and crosslinks, then cures into a solid block. This block is milled into a soft, free-flowing powder and sieved so only fine particles remain. Extra washing removes any leftover reactants.
Because it soaks up oil and gives a silky feel, Polyurea Crosspolymer-1 often appears in loose and pressed powders, oil-control primers, liquid foundations, mattifying moisturizers, sunscreen sticks and clay-type face masks. It is also blended into certain hair styling pastes to absorb excess sebum at the roots.
Polyurea Crosspolymer-1’s Cosmetic Benefits/Uses
In formulas Polyurea Crosspolymer-1 serves a single, yet useful role as an absorbent. It pulls in excess sebum and liquid from the skin surface which helps products:
• reduce unwanted shine for a matte finish
• prolong the wear time of makeup by keeping oil from breaking up pigments
• improve skin feel so creams glide on smoothly without greasiness
• thicken watery formulations without a heavy or sticky texture
Who Can Use Polyurea Crosspolymer-1
Thanks to its oil-absorbing nature Polyurea Crosspolymer-1 is especially helpful for oily, combination and normal skin types that struggle with midday shine. Acne-prone users often appreciate the ingredient as it mops up excess sebum that can mix with dead skin and clog pores. Very dry or mature skin may find it slightly too mattifying if used in high amounts, so choosing formulas that balance it with emollients is key. The powder is chemically synthesized without animal by-products so it is considered suitable for both vegans and vegetarians, though cruelty-free status depends on the finished brand’s policies.
The polymer sits on the surface and is not known to penetrate or reach the bloodstream. Because of that, no specific warnings exist for women who are pregnant or breastfeeding, but this is not medical advice. Anyone expecting or nursing should still run the full ingredient list of a product past a healthcare professional just to be safe.
Polyurea Crosspolymer-1 does not cause photosensitivity and it will not interfere with daily sunscreen use. It is also fragrance-free and inert, making it compatible with most active ingredients such as retinoids, vitamin C or acids.
Potential Side Effects/Adverse Reactions
Responses to topical Polyurea Crosspolymer-1 differ from person to person. The points below outline potential side effects that could occur, but they are uncommon when the ingredient is used correctly in a well-formulated product.
- Transient dryness or a tight skin feel, especially on already dehydrated skin
- Mild redness or irritation for those with very sensitive or compromised skin barriers
- Clogged pores if paired with heavy occlusives that prevent absorbed oil from being whisked away
- Temporary respiratory irritation if large amounts of the raw powder are inhaled during manufacturing or decanting
If any irritation or unwanted reaction appears while using a product that contains Polyurea Crosspolymer-1 discontinue use and seek advice from a qualified healthcare professional.
Comedogenic Rating
Rating: 1/5 – Polyurea Crosspolymer-1 is a large, insoluble powder that sits on the skin surface and absorbs oil without melting into pores, so it has a very low tendency to block follicles. The rating is not a perfect zero because any strong oil absorber can theoretically trap sebum if paired with heavy occlusives, though real-world cases are rare. In short, it is generally friendly for acne-prone or breakout-prone skin.
Because the particles stay on top of the skin and are easily washed away, buildup over time is unlikely. Good cleansing habits further reduce any residual risk of congestion.
Summary
Polyurea Crosspolymer-1 is mainly used as an absorbent that soaks up excess sebum, cuts shine and keeps makeup looking fresh. Its crosslinked structure forms a porous network that locks away oil while leaving a soft, silky feel, which also helps thicken watery formulas without weight.
The ingredient is still a niche choice compared with classic absorbents like silica or starches, but its smooth texture and strong oil-holding capacity are gaining attention in primers, foundations and hybrid skincare makeup.
Overall safety data show it is non irritating, non sensitising and non photosensitising. While problems are uncommon, patch testing any new product is a smart move so you can spot personal sensitivities early.