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Opacilite Durable titanium dioxide extender for high quality matt paints

  • Up to 20% titanium dioxide extension
  • Excellent exterior weathering performance
  • Outstanding paint film opacity
  • Effective above and below coating CPVC
  • For use in high quality matt and silk paints

Opacilite is a flash calcined kaolin which provides durability and exceptional opacity both above and below the CPVC, making it the first choice for TiO2 extension in high quality matt and silk paints.

Sealed voids for enhanced opacity

Opacilite is derived from naturally sourced hydrous kaolin and is further processed at high temperature to remove hydroxyl groups and to sinter kaolin particles into an aggregated structure. As opposed to conventional and soak calcined kaolin, Opacilite is produced using a very rapid calcination technique which creates sealed voids within the kaolin particles.

Opacilite™ voids foster high opacity

These voids are completely resistant to penetration by resins, solvents or water in liquid paint, enhancing wet film opacity and significantly contributing to dry hiding. The aggregated structure of Opaciliteis optimized for maximum light scattering and the combination of both internal and external voids fosters higher opacity compared to conventional calcined clay. The improvement in paint dry hiding can translate into up to 20% TiO2 savings in paint formulations.

Matting effect

Due to its irregular particle shape, which induces micro-roughness at the film surface, and hence a matting effect, Opacilite significantly reduces gloss. It is ideal for paints below CPVC such as satin finishes and exterior wall paints.

Scrub & UV resistance

Opacilite significantly improves scrub and UV resistance.

Mineral extenders usually rely on high binder absorption to give increased dry film opacity (dry hiding), but this higher binder absorption has a detrimental effect of scrub resistance. Opacilite is different because the internal voids, which provide opacity, do not absorb binder. Calcined clay particles are also relatively hard and contribute to the abrasion resistance of the dry film. Opacilite also confers improved UV weathering performance compared to other mineral pigments such as conventional kaolin and calcium carbonates.

Opacilite™ gives a unique balance of opacity, matting and scrub resistance

We offer a full range of bespoke formulation and technical and process support services to help you match the right mineral grade to your application requirement.

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