Cristobalite (silica, chemical formula SiO2) is the result of the calcination of quartz at a temperature of 1500°C:
Cristobalite can be characterised by:
- High brightness
- Relatively high Mohs hardness of 6.5
- Relatively low refractive index, making it a transparent filler in various binders
- Easy wetting
- High inertness in various media
- Transparency for UV-radiation (ie. suitable for UV-curing processes).
Note when using cristobalite: depending on the particle size distribution of the product, it can be labelled (STOT RE 2 or STOT RE 1). For more detailed information, visit www.safesilica.eu.
|Colour (D65/ 10°) L*||98||[-]|
(1): Tamisé: > 500 µm = < 1%
Production locations Sibelite
Cristobalite will provide:
- Chemical resistance: due to its inert nature, cristobalite provides good chemical resistance compared to conventional fillers.
- Abrasion resistance: due to its hardness of 6.5 on Mohs scale, cristobalite will increase the coating’s resistance to wear.
- Clarity: due to its fairly low refractive index, cristobalite becomes transparent when combined with certain binder systems.
- UV-curing compatibility: being transparent for UV radiation, cristobalite does not block the curing mechanism.
- Gloss control: with the availability of ultrafine and medium size cristobalite flour grades, it is possible to apply coatings with a broad range of gloss levels.
- Pore and grain filling properties (sealer): with low impact on the viscosity, cristobalite can be used as a mineral filler in sealers to give them more body.
- Stain resistance: cristobalite acts as a supporting mineral filler in stain resistant coatings.