Quaternium-91 ●
TL;DR. This ingredient is a cationic hair-conditioning agent that helps reduce static, improve wet combing, and leave a smooth feel on damaged or negatively charged hair fibers.
What does Quaternium-91 do in a cosmetic formula?
This ingredient is a cationic hair-conditioning agent that helps reduce static, improve wet combing, and leave a smooth feel on damaged or negatively charged hair fibers.
Is Quaternium-91 clean?
Clean-beauty frameworks often flag this material because it is a synthetic cationic conditioning compound with irritation potential at higher levels and aquatic-impact concerns. It is more common in conventional rinse-off hair care than in stricter clean formulations.
Is Quaternium-91 sustainable?
This material is synthetic and typically relies on petrochemical and fatty-chain inputs, with feedstock details depending on the supplier. Cationic conditioning compounds can bind strongly to sludge and sediment, so environmental persistence and aquatic exposure are the main sustainability concerns.
Is Quaternium-91 COSMOS-approved?
It is not a strong fit for COSMOS-natural or COSMOS-organic standards, and it is generally treated as outside the preferred palette for those frameworks. From a Green Chemistry perspective, its strong cationic charge, limited biodegradability profile, and aquatic-impact concerns weigh against it.
How does Quaternium-91 work chemically?
The molecule has a permanently charged nitrogen center and long hydrophobic chains, which drives strong adsorption onto negatively charged hair keratin. It is typically used at low levels in conditioners and masks, works best in mildly acidic systems, and is poorly compatible with anionic surfactants.
Last updated 2026-05-14