White Pigment Opacifier

The most common ceramic opacifiers include zirconium silicate (ZrSiO₄), zirconium oxide (ZrO₂), tin oxide (SnO₂), and titanium dioxide (TiO₂). Zirconium silicate is the most widely used in the modern ceramics industry for tile and sanitaryware glazes due to its stability, consistent opacity, and cost effectiveness.

Opacifier loading depends on the glaze system and required opacity level. Typically, 8–15% by weight for zirconium-based opacifiers in tile glaze, and 5–12% for premium tin-based opacifiers in tableware. The precise dosage is optimised for each glaze chemistry and firing temperature.

The particle size of the opacifier determines its light-scattering efficiency. Particles in the range of 0.5–2 microns are most effective at scattering visible light wavelengths. Finer particle sizes generally deliver better opacity at lower loadings, while coarser particles may require higher loading for equivalent opacity.

Yes. Opacifiers are extensively used in tile engobe (the intermediate coating between body and glaze) to improve whiteness of the engobe layer, enhance the barrier between body and glaze, and provide a bright, consistent base for coloured decorative glazes applied on top.

Yes. The addition of opacifier affects the thermal expansion of the glaze system. Zirconium silicate opacifiers generally have a lower thermal expansion than most glaze matrices, so their loading must be balanced to ensure the fired glaze thermal expansion matches the ceramic body, preventing crazing or shivering.