Borosilicate glasses with low alkali content

Abstract

According to one embodiment, a glass may include from about 50 mol. % to about 70 mol. % SiO2; from about 12 mol. % to about 35 mol. % B2O3; from about 4 mol. % to about 12 mol. % Al2O3; greater than 0 mol. % and less than or equal to 1 mol. % alkali metal oxide, wherein Li2O is greater than or equal to about 20% of the alkali metal oxide; from about 0.3 mol. % to about 0.7 mol. % of Na2O or Li2O; and greater than 0 mol. % and less than 12 mol. % of total divalent oxide, wherein the total divalent oxide includes at least one of CaO, MgO and SrO, and wherein a ratio of Li2O (mol. %) to (Li2O (mol. %)+(Na2O (mol. %)) is greater than or equal 0.4 and less than or equal to 0.6. The glass may have a relatively low high temperature resistivity and a relatively high low temperature resistivity.

Dependencies are inferred from the claim text.