A process for the manufacture of a glass-ceramic article exhibiting properties of resistance to scratches, greasy marks, adhesion of dirt and light scattering. The glass-ceramic article includes a surface, the surface arithmetic roughness of which is between 2 μm and 7 μm and the roughness being obtained using a chemical surface treatment. The glass-ceramic article is particularly suitable for use as a cooking surface and/or as surface for the preparation of foodstuffs.

Embodiments of a glass-based article including a first surface and a second surface opposing the first surface defining a thickness (t) of about 3 millimeters or less (e.g., about 1 millimeter or less), and a stress profile, wherein all points of the stress profile between a thickness range from about 0.Math.t up to 0.3.Math.t and from greater than 0.7.Math.t, comprise a tangent that is less than about −0.1 MPa/micrometers or greater than about 0.1 MPa/micrometers, are disclosed. In some embodiments, the glass-based article includes a non-zero metal oxide concentration that varies along at least a portion of the thickness (e.g., 0.Math.t to about 0.3.Math.t). In some embodiments, the concentration of metal oxide or alkali metal oxide decreases from the first surface to a point between the first surface and the second surface and increases from the point to the second surface. The concentration of the metal oxide may be about 0.05 mol % or greater or about 0.5 mol % or greater throughout the thickness. Methods for forming such glass-based articles are also disclosed.

Lithium silicate-diopside glass ceramics are described which are characterized by a controllable translucence and can be satisfactorily processed mechanically and therefore can be used in particular as restoration material in dentistry.

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 transparent β-quartz glass ceramic is provided. The glass ceramic includes a primary crystal phase including a β-quartz solid solution, a secondary crystal phase including tetragonal ZrO.sub.2, and a lithium aluminosilicate amorphous phase. The glass ceramic may be ion exchanged utilizing molten nitrate salt baths. Methods for producing the glass ceramic are also provided.

Glass-based articles are provided that exhibit improved fracture resistance. The relationships between properties attributable to the glass composition and stress profile of the glass-based articles are provided that indicate improved fracture resistance.

A product having a transparent volume-coloured glass-ceramic is provided. The glass-ceramic includes, based on oxide, 58-72% by weight SiO.sub.2, 16-26% by weight Al.sub.2O.sub.3, 1.0-5.5% by weight Li.sub.2O, 2.0-<4.0% by weight TiO.sub.2, 0-<2.0 by weight ZnO, and 0.005-0.12% by weight MoO.sub.3, and where the glass-ceramic, based on a thickness of 4 mm, has a luminous transmittance τ.sub.vis of 0.5%-3.5%, and where the glass-ceramic has the property that after passage through the glass-ceramic, based on a thickness of 4 mm, light of the standard illuminant D65 has a colour locus in the white region A1 that in the CIExyY-2° chromaticity diagram is defined by the following coordinates:

TABLE-US-00001 A1 0.3 0.27 0.28 0.315 0.35 0.38 0.342 0.31 0.3 0.27.

The invention relates to glass articles suitable for use as electronic device housing/cover glass which comprise a glass ceramic material. Particularly, a cover glass comprising an ion-exchanged glass ceramic exhibiting the following attributes (1) optical transparency, as defined by greater than 90% transmission at 400-750 nm; (2) a fracture toughness of greater than 0.6 MPa.Math.m.sup.1/2; (3) a 4-point bend strength of greater than 350 MPa; (4) a Vickers hardness of at least 450 kgf/mm.sup.2 and a Vickers median/radial crack initiation threshold of at least 5 kgf; (5) a Young's Modulus ranging between about 50 to 100 GPa; (6) a thermal conductivity of less than 2.0 W/m° C., and (7) and at least one of the following attributes: (i) a compressive surface layer having a depth of layer (DOL) greater and a compressive stress greater than 400 MPa, or, (ii) a central tension of more than 20 MPa.

The present invention relates generally to silicate-based coatings and to methods to make and apply same. In one embodiment, the silicate-coatings of the present invention are formed from a two part mixture of phosphate-based component and a glass-based component. In another embodiment, the silicate-based coatings of the present invention are free from any organic materials.

Provided is a dielectric ceramic composition comprising a main component of forsterite and calcium strontium titanate. A content ratio of forsterite in the main component is from 84.0 to 92.5 parts by mole, and a content ratio of calcium strontium titanate is from 7.5 to 16.0 parts by mole. (Sr+Ca)/Ti in the calcium strontium titanate is from 1.03 to 1.20 in terms of a molar ratio. With respect to a total of 100 parts by mass of the main component and a subcomponent except for Li-containing glass, from 2 to 10 parts by mass of Li-containing glass is added. The Li-containing glass includes Al.sub.2O.sub.3 in an amount of from 1% by mass to 10% by mass.