Reducing usage of zirconiasilicate in opaque white sanitaryware glazes by calsined caolin usage

Zirconium silicate is a common and expensive opacifier component in sanitaryware opaque glazes. The high optical refractive index of zircon (ZrSiO4) contributes opacity and promotes whiteness of the surface. The high optical refractive index of zirconium silicate is necessary to obtain acceptable white camouflage influence to cover the dark beige color of the soft porcelain body. As a known opacifier the zircon is most effective ingredient on the cost of sanitary glaze recipes. There are many studies on decrease of usage percentage of zirconium silicate in opaque glaze recipes. Alternative calcined caolin adapted opaque glazes are reproduced through an exemplary industrial glaze recipe to get the acceptable technical glaze properties with low zircon content in this study. Alternative recipe combinations have been tried to obtain lower cost sanitary opaque glaze of R2O-RO-(ZrO2)-B2O3-Al2O3-SiO2 glass and ceramic systems. As a result, the notable zircon usage reduction percentage has been obtained without any technical specification lost as industrially.