Polyquaternium-91
INCI: POLYQUATERNIUM-91
Reviewed by Kate · Last updated 18 Aug 2026
What Is Polyquaternium-91?
Polyquaternium-91 is a polymeric quaternary ammonium salt of hydroxypropyl methacrylate and polyethylene glycol methacrylate quaternized with ethyltrimonium chloride methacrylate.
Its declared cosmetic functions are film forming and hair conditioning.
Source: European Commission CosIng inventory.
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