Glass-ceramic materials process of their production and use

摘要

The present invention refers to glass-ceramics consisting of the mixtures (I): ZrO₂-SiO₂-Me^IIO, or (II) SiO₂-Me^IIIO₂-Me^IIO, wherein: Me^II is chosen in the group consisting of: Ca, Ba, Mg, Zn or mixture thereof; Me^III is chosen in the group consisting of Al, B or mixtures thereof; each of the above said constituents being present in determined quantities; the invention refers also to a process for preparing the glass-ceramics above defined; porcelain stonewares and glazes containing them and their use for preparing ceramic items.