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Ingredient · INCI reference

Quaternium-18 Hectorite

Quaternium-18 hectorite is an organically modified hectorite clay used in cosmetics as a rheology modifier and suspending agent.

What it is

Quaternium-18 hectorite is hectorite clay treated with the quaternary ammonium compound quaternium-18, which makes it disperse and swell in oil phases. In sunscreens it thickens oil-based and anhydrous systems and helps suspend mineral UV filters and pigments to keep them uniformly distributed. It is commonly used to give water-in-oil and oil-rich formulas stable structure and a consistent texture.

Safety & warnings

Organically modified clays of this type are generally well tolerated and have low irritation potential at typical use levels. It is not a fragrance allergen and, being an inorganic clay, is not associated with comedogenicity concerns.

Origin & sourcing

Semi-synthetic; it is naturally sourced hectorite clay chemically modified with a quaternary ammonium compound.

Questions everyone asks

What does quaternium-18 hectorite do in a formula?

It thickens oil-based formulas and keeps mineral filters and pigments evenly suspended for a stable, consistent texture.

How is it different from quaternium-18 bentonite?

Both are organoclays modified with quaternium-18, but this one is based on hectorite clay rather than bentonite, giving slightly different rheology.

Sources & references

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