Effects Of Glass Frit Oxides On Crystallization And Zircon Pigment Dissolution In Whiteware Coatings

In experimental whiteware coatings comprised of zircon pigment and multi-oxide silicate glass frits that incorporated Zr02, the quantity, size, and morphology of zircon that precipitated during "fast-firing" were mainly dependent upon the Zn0, Sr0, and Al203: alkali levels. In these frits, little or no zircon pigment dissolution occurred, and zircon crystallization was nearly complete by 1000 deg C. Microstructures of the coatings were consistent over a range of peak firing temperatures from 1000-1100 deg C. Fritted Zn0 in these coatings stimulated zircon crystallization and produced high opacity. Replacing Zn0 with Sr0 in the same frits prevented zircon from precipitating and resulted in transparent coatings.