Transparent b-quartz glass-ceramics with specific transmission

Abstract

The present invention relates to a transparent lithium aluminosilicate (LAS) glass-ceramic containing a β-quartz solid solution as the main crystalline phase, the composition of which, expressed in percentages by mass of oxides, contains 60 to 67.5% SiO2, 18 to 22% Al2O3, 2.5 to 3.3% Li2O, 0 to 1.5% MgO, 1 to 3.5% ZnO, 0 to 4% BaO, 0 to 4% SrO, 0 to 2% CaO, 3.1 to 5% TiO2, 0.4 to 1.3% ZrO2, 0 to 1% Na2O, 0 to 1% K2O, 0 to 5% P2O5, 0.02 to 0.1% CoO, 0.05 to 0.25% Fe2O3, with (0.74 MgO + 0.19 BaO + 0.29 SrO + 0.53 CaO + 0.48 Na2O + 0.32 K2O) / Li2O < 0.8, and optionally up to 2% of at least one refining agent, the composition being free of V2O5 with the exception of unavoidable traces. It also relates to an article, consisting at least in part of a glass-ceramic, chosen in particular from a cooking plate and a glazing. It also relates to a lithium aluminosilicate glass, precursor of the glass-ceramic, and the process for producing the article.

Dependencies are inferred from the claim text.