A glass composition includes from 55.0 mol % to 75.0 mol % SiO.sub.2; from 8.0 mol % to 20.0 mol % Al.sub.2O.sub.3; from 3.0 mol % to 15.0 mol % Li.sub.2O; from 5.0 mol % to 15.0 mol % Na.sub.2O; and less than or equal to 1.5 mol % K.sub.2O. The glass composition has the following relationships: Al.sub.2O.sub.3+Li.sub.2O is greater than 22.5 mol %, R.sub.2O+RO is greater than or equal to 18.0 mol %, R.sub.2O/Al.sub.2O.sub.3 is greater than or equal to 1.06, SiO.sub.2+Al.sub.2O.sub.3+B.sub.2O.sub.3+P.sub.2O.sub.5 is greater than or equal to 78.0 mol %, and (SiO.sub.2+Al.sub.2O.sub.3+B.sub.2O.sub.3+P.sub.2O.sub.5)/Li.sub.2O is greater than or equal to 8.0. The glass composition may be used in a glass article or a consumer electronic product.

A glass composition includes from 55.0 mol % to 75.0 mol % SiO.sub.2; from 8.0 mol % to 20.0 mol % Al.sub.2O.sub.3; from 3.0 mol % to 15.0 mol % Li.sub.2O; from 5.0 mol % to 15.0 mol % Na.sub.2O; and less than or equal to 1.5 mol % K.sub.2O. The glass composition has the following relationships: Al.sub.2O.sub.3+Li.sub.2O is greater than 22.5 mol %, R.sub.2O+RO is greater than or equal to 18.0 mol %, R.sub.2O/Al.sub.2O.sub.3 is greater than or equal to 1.06, SiO.sub.2+Al.sub.2O.sub.3+B.sub.2O.sub.3+P.sub.2O.sub.5 is greater than or equal to 78.0 mol %, and (SiO.sub.2+Al.sub.2O.sub.3+B.sub.2O.sub.3+P.sub.2O.sub.5)/Li.sub.2O is greater than or equal to 8.0. The glass composition may be used in a glass article or a consumer electronic product.

A seamless three-dimensional cover (1) for an electronic device (2), the seamless three-dimensional cover (1) comprising of at least one glass base layer (3) and at least one glass rim layer (4). At least one layer of color inducing film (5) is arranged between at least one of the base layer (3) and the rim layer (4), or between two adjacent rim layers (4). The base layer (3), the rim layer(s) (4), and the layer of color inducing film (5) are fused together to form the seamless three-dimensional cover (1). This facilitates a strong and durable three-dimensional cover, which cover is translucent as well as at least partially colored. Furthermore, the cover does not affect the function of components such as millimeter-wave antennas.

A seamless three-dimensional cover (1) for an electronic device (2), the seamless three-dimensional cover (1) comprising of at least one glass base layer (3) and at least one glass rim layer (4). At least one layer of color inducing film (5) is arranged between at least one of the base layer (3) and the rim layer (4), or between two adjacent rim layers (4). The base layer (3), the rim layer(s) (4), and the layer of color inducing film (5) are fused together to form the seamless three-dimensional cover (1). This facilitates a strong and durable three-dimensional cover, which cover is translucent as well as at least partially colored. Furthermore, the cover does not affect the function of components such as millimeter-wave antennas.

Disclosed herein are glass-based articles having a first surface having an edge, wherein a maximum optical retardation of the first surface is at the edge and the maximum optical retardation is less than or equal to about 40 nm and wherein the optical retardation decreases from the edge toward a central region of the first surface, the central region having a boundary defined by a distance from the edge toward a center point of the first surface, wherein the distance is ½ of the shortest distance from the edge to the center point.

Disclosed herein are glass-based articles having a first surface having an edge, wherein a maximum optical retardation of the first surface is at the edge and the maximum optical retardation is less than or equal to about 40 nm and wherein the optical retardation decreases from the edge toward a central region of the first surface, the central region having a boundary defined by a distance from the edge toward a center point of the first surface, wherein the distance is ½ of the shortest distance from the edge to the center point.

The present invention relates to a 3D printer printhead, a 3D printer using the same, a method for manufacturing a molded product by using the 3D printer, a method for manufacturing an artificial tooth by using the 3D printer, and a method for manufacturing a machinable glass ceramic molded product by using the 3D printer, the 3D printer printhead comprising: an inlet through which glass wire, which is a raw material, is introduced; a heating means for heating the glass wire introduced through the inlet; a melting furnace for providing a space in which the glass wire is fused; and a nozzle connected to the lower part of the melting furnace so as to temporarily store the fused glass or discharge a targeted amount of the fused glass, wherein the melting furnace includes an exterior frame made from a heat resistant material and an interior frame having a crucible shape, and the interior frame is made from platinum (Pt), a Pt alloy or graphite, which have a low contact angle, or a material having a surface coated with Pt or a diamond-like carbon (DLC) so as to prevent the fused glass from sticking thereto. According to the present invention, the molded product, the artificial tooth, and the machinable glass ceramic molded product can be manufactured with excellent mechanical properties, thermal durability, chemical durability and oxidation resistance and outstanding texture by using the glass wire as a raw material.

The present invention relates to a 3D printer printhead, a 3D printer using the same, a method for manufacturing a molded product by using the 3D printer, a method for manufacturing an artificial tooth by using the 3D printer, and a method for manufacturing a machinable glass ceramic molded product by using the 3D printer, the 3D printer printhead comprising: an inlet through which glass wire, which is a raw material, is introduced; a heating means for heating the glass wire introduced through the inlet; a melting furnace for providing a space in which the glass wire is fused; and a nozzle connected to the lower part of the melting furnace so as to temporarily store the fused glass or discharge a targeted amount of the fused glass, wherein the melting furnace includes an exterior frame made from a heat resistant material and an interior frame having a crucible shape, and the interior frame is made from platinum (Pt), a Pt alloy or graphite, which have a low contact angle, or a material having a surface coated with Pt or a diamond-like carbon (DLC) so as to prevent the fused glass from sticking thereto. According to the present invention, the molded product, the artificial tooth, and the machinable glass ceramic molded product can be manufactured with excellent mechanical properties, thermal durability, chemical durability and oxidation resistance and outstanding texture by using the glass wire as a raw material.

A plate-like chemically strengthened glass having a compression stress layer on the surface of the glass, wherein the compressive stress value (CS.sub.0) at the glass surface of is 500 MPa or more, the plate thickness (t) is 400 .Math.m or more, the compressive stress depth of layer (DOL) is (t × 0.15) .Math.m or more, the compressive stress values (CS.sub.1) and (CS.sub.2) when the depth from the glass surface is ¼ and ½, respectively, are 50 MPa or more, m.sub.1 expressed by {m.sub.1 = (CS.sub.1 - CS.sub.2/(DOL/4 - DOL/2)} is -1.5 MPa/.Math.m or more, m.sub.2 expressed by {m.sub.2 = (CS.sub.2/(DOL/2 - DOL)} is 0 MPa/.Math.m or less, and m.sub.2 is less than m.sub.1.

Glass-based articles that include a hydrogen-containing layer extending from the surface of the article to a depth of layer. The hydrogen-containing layer includes a hydrogen concentration that decreases from a maximum hydrogen concentration to the depth of layer. The glass-based articles exhibit a high Vickers indentation cracking threshold. Glass compositions that are selected to promote the formation of the hydrogen-containing layer and methods of forming the glass-based article are also provided.