Underglaze engobe for ceramic facing tiles.

A formula for white underglaze engobe is developed based on porcelain-faience waste (after the first firing) to be used on facing tiles with a dark-colored ceramic base. Applying this engobe to a dried tile ensures good sinterability of the engobe to the tile at higher temperatures of the first firing. This makes it possible to simplify the engobe composition and to improve the quality parameters of the tile itself and of the glaze coating. [ABSTRACT FROM AUTHOR]