High strain point aluminosilicate glasses

摘要

Described herein are alkali-free, boroalumino silicate glasses exhibiting desirable physical and chemical properties for use as substrates in flat panel display devices, such as, active matrix liquid crystal displays (AMLCDs) and active matrix organic light emitting diode displays (AMOLEDs). In accordance with certain of its aspects, the glasses possess good dimensional stability as a function of temperature.

主权项

1. A glass substantially free of alkali metals comprising, in mole percent on an oxide basis: SiO2 70.31-72.5, Al2O3 11-13.5, B2O3 1-5, MgO 3-5, CaO 4-6.5, SrO 0-3, BaO 1.5-5, where SiO2, Al2O3, B2O3, MgO, CaO, SrO and BaO represent the mole percents of the oxide components;
wherein: (i) the glass has an annealing point greater than 785° C., (ii) the glass satisfies the following relationship:
T35k−Tliq>0.25T35k−225° C.,where Tliq is the liquidus temperature of the glass and T35k is the temperature at which the glass has a viscosity of 35,000 poise,
(iii) the Sb2O3 content of the glass is at most 0.05 mole percent, and (iv) the glass is made from batch materials that do not include Y2O3 or La2O3 as a component.