POLYQUATERNIUM-4 is graded A (Safe) by Expert·ING, based on COSING regulatory data.

POLYQUATERNIUM-4

Safety grade: A

This is a synthetic polymer (plastic-like substance) that's commonly used in hair and skin care products. It's designed to reduce static electricity and create a protective coating on your skin or hair.

It eliminates frizz and static electricity while forming a lightweight, invisible film on the skin or hair surface to improve texture and smoothness.

Graded using: COSING.

Last verified: May 26, 2026