Improvement of surface properties in sanitaryware glazes

In this study, it was aimed that improvement surface quality of sanitary ware glazes with using a standard glaze recipe. Particle size distribution of glaze suspension, weight percentage of zirconium silicate in recipe, and particle size of quartz were determined as effective parameters. Within this scope, viscosity, density, particle size distribution and hot stage microscopy analysis were performed for unfired products. XRD, XRF, SEM, dilatometry analysis and colour and roughness measurements were completed for fired products. Particle size of suspensions was analysed by Mastersizer 2000, Malvern Instruments with using laser diffraction method. It was observed that coarser particles decreased the brightness of the surface. Preparing coarser particle size glaze affected after firing properties as some quartz particles remained without melting and observed in mineralogical analyse. Therefore, surface roughness increased on glaze surface. Thus, optimum particle size distribution range should be between 7.5 and 8.5µm. Secondly; standard recipe was based on to determine the effect of zirconium silicate on glaze surface. Zircon was used between 3-12 % in weight in the recipe. Increasing zircon percentage provided higher brightness and whiteness values as expected. It was determined that optimum zircon percentage should be 10-12 % in weight in opaque glaze recipe. Finally, effect of quartz particle size on glaze surface was investigated. According to results, thinner quartz particles had more contribution to glassy phase because these particles could be dissolved in glassy phase. For that reason improvements were observed in brightness and whiteness Keywords: Ceramic, Opaque Glaze, Zircon, Particle Size Distribution, Rheology