Use of alumina ceramic coatings
Calcined and fused aluminas in ceramic tiles are used to confer both resistance to abrasion and resistance to chemical attack and also give the opacification effect . For this reason, alumina is used in compositions of engobes, glazes and inks.
In its use in glazing, alumina has a wide range of functions it can be used to ensure the increase of the PEI coating to generate optical effects semi-gloss, matte, fusibility and control the expansion of the glaze. The addition of alumina can be given either in the grinding of raw materials or in the dispersion of the glaze / correction phase characteristics.
The final effect of the alumina addition depends on its physicochemical characteristics. There are different types of calcined aluminas, each of which is produced by a different type of processing. Thus, the microstructural aluminas have physical differences, which give different behaviors in the preparation and firing of the glaze process.