Abstract: The invention relates glass ceramic articles suitable for use as electronic device housing or enclosures which comprise a glass-ceramic material. Particularly, a glass-ceramic article housing/enclosure comprising a glass-ceramic material exhibiting both radio and microwave frequency transparency, as defined by a loss tangent of less than 0.5 and at a frequency range of between 15 MHz to 3.0 GHz, a fracture toughness of greater than 1.5 MPa·m1/2, an equibiaxial flexural strength (ROR strength) of greater than 100 MPa, a Knoop hardness of at least 400 kg/mm2, a thermal conductivity of less than 4 W/m° C. and a porosity of less than 0.1%.

Abstract: The invention is directed to a method for reducing striae in ultra-low expansion glass, for example, silica-titania glass, by heat-treating the glass at temperatures above 1600° C. for a time in the range of 72-288 hours. The silica-titania glass is formed by substantially simultaneously forming, collecting and consolidating a silica-titania soot formed in one or a plurality of burners using silicon-containing feedstock and a titanium-containing feedstock. In one embodiment of the invention the glass is heat treated without forcing the glass to flow or “move”. The invention was found to reduce the magnitude of striae in an ultra-low expansion glass by at least 50%, and particularly reduces most of the “higher frequency” striae.

Abstract: An alkali aluminosilicate glass article, said alkali aluminosilicate glass having a surface compressive stress of at least about 200 MPa, a surface compressive layer having a depth of at least about 30 ?m, a thickness of at least about 0.3 mm and an amphiphobic fluorine-based surface layer chemically bonded to the surface of the glass. In one embodiment the glass has an anti-reflective coating applied to one surface of the glass between the chemically strengthened surface of the glass and the amphiphobic coating. In another embodiment the surface of the chemically strengthened glass is acid treated using a selected acid (e.g., HCL, H2SO4, HClO4, acetic acid and other acids as described) prior to placement of the amphiphobic coating or the anti-reflective coating.