Thermal and Physical Properties of White-Opaque Sanitary Glazes Using Lampang Pottery Stone as Raw Materials

The aim of this work was to determine thermal and physical properties of white-opaque sanitary glazes. Lampang pottery stone was used to replace silica (G2) and feldspar (G3) in the commercial sanitary glaze (G1). All formulations of glazes developed from Seger formula calculation and the glaze slurry was prepared by wet milling, green glazing on commercial ceramic body and firing at 1200๐C with heating rate of 3๐C/min by using electric kiln. Melting characteristics, specular gloss, lightness, color, and thermal expansion behavior of all sanitary glazes were investigated. As a result, the glaze G2 was a good reflecting surface with high lightness value. Linear thermal expansion difference at 500๐C between the glaze G2 and the commercial ceramic body was-0.015%. This glaze-body fit was, therefore, under small compression and more compatible to ceramic sanitary products.