Abstract: Borosilicate glasses are disclosed having (in weight %) 66-76% SiO2, 0-8% Al2O3, 10-18% B2O3, 0-4% Li2O, 0-12% Na2O, 0-12% K2O, 1-1.5% Ag, 1.5-2.5% Cl? and 0.01-0.06% of a summed amount of CuO and NiO, wherein the glass composition is bleachable upon exposure to ultraviolet irradiation from a stable state color or shade to a lighter color or shade. Such reverse photochromic borosilicate glass compositions may be thermally darkenable. The borosilicate glasses may be strengthened via ion-exchange strengthening treatment. The borosilicate glasses may retain their reverse photochromic and thermally darkenable properties even after ion-exchange strengthening treatment.

Abstract: Borosilicate glasses are disclosed having (in weight %) 66-76% SiO2, 0-8% Al2O3, 10-18% B2O3, 0-4% Li2O, 0-12% Na2O, 0-12% K2O, 1-1.5% Ag, 1.5-2.5% Cl? and 0.01-0.06% of a summed amount of CuO and NiO, wherein the glass composition is bleachable upon exposure to ultraviolet irradiation from a stable state color or shade to a lighter color or shade. Such reverse photochromic borosilicate glass compositions may be thermally darkenable. The borosilicate glasses may be strengthened via ion-exchange strengthening treatment. The borosilicate glasses may retain their reverse photochromic and thermally darkenable properties even after ion-exchange strengthening treatment.

Abstract: Borosilicate glasses are disclosed having (in weight %) 66-76% SiO2, 0-8% Al2O3, 10-18% B2O3, 0-4% Li2O, 0-12% Na2O, 0-12% K2O, 1-1.5% Ag, 1.5-2.5% Cl? and 0.01-0.06% of a summed amount of CuO and NiO, wherein the glass composition is bleachable upon exposure to ultraviolet irradiation from a stable state color or shade to a lighter color or shade. Such reverse photochromic borosilicate glass compositions may be thermally darkenable. The borosilicate glasses may be strengthened via ion-exchange strengthening treatment. The borosilicate glasses may retain their reverse photochromic and thermally darkenable properties even after ion-exchange strengthening treatment.

Abstract: Ion exchangeable boroaluminosilicate glasses having high levels of intrinsic scratch resistance are provided. The glasses include the network formers SiO2, B2O3, and Al2O3, and at least one of Li2O, Na2O, and K2O. When ion exchanged these glasses may have a Knoop scratch initiation threshold of at least about 40 Newtons (N). These glasses may also be used to form a clad layer for a glass laminate in which the core layer has a coefficient of thermal expansion that is greater than that of the clad glass.

Abstract: Borosilicate glasses are disclosed having (in weight %) 66-76% SiO2, 0-8% Al2O3, 10-18% B2O3, 0-4% Li2O, 0-12% Na2O, 0-12% K2O, 1-1.5% Ag, 1.5-2.5% Cl? and 0.01-0.06% of a summed amount of CuO and NiO, wherein the glass composition is bleachable upon exposure to ultraviolet irradiation from a stable state color or shade to a lighter color or shade. Such reverse photochromic borosilicate glass compositions may be thermally darkenable. The borosilicate glasses may be strengthened via ion-exchange strengthening treatment. The borosilicate glasses may retain their reverse photochromic and thermally darkenable properties even after ion-exchange strengthening treatment.