Huntite (magnesium calcium carbonate, Mg3Ca(CO3)4) is an ultrafine, lamellar mineral. Being sub-micron makes it suitable as an extender for TiO2. Huntite is available with a stearic acid surface treatment, changing its nature from hydrophilic to hydrophobic. Huntite can be characterised by:
- A high brightness
- Lamellar particle shape
- Sub-micron particle size.
|Hardness (Mohs)||2 – 3||[-]|
|Refractive index||1.61 – 1.64||[-]|
|Colour (D65/ 10°) L*||98||–||[-]|
[g/ 100 g]
|H5 F11.0||3||57||1% stearic acid|
|H5 F12.0||3||57||2% stearic acid|
|H5 F13.0||3||57||3% stearic acid|
Production location Portafill H
Huntite will provide:
- Rheology control: due to its lamellar shape and fairly high oil absorption compared to other mineral fillers, huntite has an impact on the rheology profile of the sealant and/or adhesive. When applying shear, the lamellar particles will align and provide a low viscosity. When shear is removed, the lamellar particles lose their orientation and cause the viscosity to increase above the level expected when the particles had a more regular shape.
- TiO2 extension: being an ultrafine, lamellar particle, huntite can be used to open up TiO2 agglomerates and to keep them separated during the drying/curing process. That way, the TiO2 is more effectively used, which means that the amount can be lowered while maintaining its properties. As a result, a cost reduction can be achieved.