POLYQUATERNIUM-91 is graded A (Safe) by Expert·ING, based on COSING regulatory data.

POLYQUATERNIUM-91

Safety grade: A

This is a conditioning polymer that creates a thin, protective layer on hair strands. It's a lab-created ingredient designed to improve how hair feels and looks by adding smoothness and shine.

It coats the hair to reduce frizz, add moisture, improve manageability, and create a protective film that makes hair appear smoother and shinier.

Graded using: COSING.

Last verified: May 26, 2026

Other Film Forming ingredients