Disteardimonium Hectorite

Disteardimonium hectorite is a quaternary-ammonium-treated clay used primarily as a rheology modifier/suspending agent in color cosmetics and anhydrous creams, typically at low levels (~0.5–5%). In clinical use and patch-testing experience, it is generally well tolerated with irritation being uncommon, but the quaternary ammonium modification means a small subset of highly reactive or eczema-prone patients can experience mild irritation, especially with frequent occlusive use. Given the low but non-zero risk in compromised skin, it fits best as very gentle rather than inert. Safety Notes: Disteardimonium Hectorite is most often used as an oil-phase rheology modifier/suspending agent in anhydrous or low-water systems (makeup, sunscreens, cleansing balms, oil gels), where it can be present at ~0.1–0.5% for light stabilization and viscosity adjustment. In higher-structure consumer products such as oil gels, stick/cream formats, and heavily pigmented suspensions, levels commonly rise to ~1–3%, and specialty anhydrous gel/structuring systems available OTC can reach about 8–10% when used as a primary gellant (typically activated with a polar activator like propylene carbonate). Leave-on and rinse-off usage overlaps, but the highest levels are mainly seen in anhydrous leave-on color cosmetics and oil-based sunscreens/primers rather than conventional emulsions.