The present invention relates to a novel multi-layered zirconia dental blank comprising at least two reverse layers. Further, the invention relates to a process for the preparation of such a multi-layered zirconia dental blank. The invention also relates to the use of such a multi-layered zirconia dental blank for the production of a dental article. Preferred dental articles are artificial teeth, inlays, onlays, bridges, crowns, veneers, facings, crown frameworks, bridged frameworks, implants, abutments, copings or orthodontic appliances. Moreover, the invention relates to a process for producing a dental article out of such a multi-layered zirconia dental blank.

A zirconia ceramic material for use in dental applications is provided comprising an yttria-stabilized zirconia material stabilized with 5 mol % yttria to 8 mol % yttria, and methods for making a sintered body from the ceramic material. The zirconia ceramic materials exhibit both enhanced translucency and a flexural strength of at least 300 MPa, or at least 500 MPa, when fully sintered.

The present invention provides a coloring solution for zirconia, which, when used on zirconia before firing of the zirconia, causes the zirconia to exhibit only a slight color difference before and after the firing and thus enables accurate prediction of the post-firing color tone of the zirconia. The present invention relates to a coloring solution for zirconia, comprising: a coloring agent (A) that is decolorized after firing of zirconia; and a metal ion solution (B), wherein, when zirconia is colored with the coloring solution and then subjected to firing, the color difference of the zirconia before and after the firing satisfies ΔL*≤5.8, Δa*≤2.4, and Δb*≤4.3.

A sintered body comprises zirconia including a stabilizer element dissolved therein and a lanthanoid element dissolved therein, the lanthanoid element having an ionic radius larger than the atomic radius of zirconium. The content of monoclinic zirconia after a hydrothermal treatment at 140° C. for 24 hours is less than 25%. The sintered body includes a spinel compound including aluminum and a coloring element.

A red zirconium-oxide sintered body includes oxide of cerium, auxiliary metal oxide and oxide of zirconium, wherein the auxiliary metal oxide includes any one or a combination of at least two of oxide of yttrium, oxide of magnesium, oxide of calcium and oxide of ytterbium; the red zirconium-oxide sintered body satisfies conditions that the oxide of cerium has a content of 0.2˜1.5 mol %; the oxide of cerium comprises trivalent cerium oxide; a sum of contents of the oxide of cerium and the auxiliary metal oxide is 1.1˜2.5 mol %; and the sintered body has fracture toughness≥8 MPa.Math.m.sup.1/2. The zirconium-oxide sintered body has red appearance and toughness more than 8 MPa.Math.m.sup.1/2, and can be used for products such as mobile phone backboards, ornaments and dial plates.

A corrosion-resistant component configured for use with a semiconductor processing reactor, the corrosion-resistant component comprising: a) a ceramic insulating substrate; and, b) a white corrosion-resistant non-porous outer layer associated with the ceramic insulating substrate, the white corrosion-resistant non-porous outer layer having a thickness of at least 50 μm, a porosity of at most 1%, and a composition comprising at least 15% by weight of a rare earth compound based on total weight of the corrosion-resistant non-porous layer; and, c) an L* value of at least 90 as measured on a planar surface of the white corrosion-resistant non-porous outer layer. Methods of making are also disclosed.

A process for preparing roofing granules includes forming kaolin clay into green granules and sintering the green granules at a temperature of at least 900 degrees Celsius to cure the green granules until the crystalline content of the sintered granules is at least ten percent as determined by x-ray diffraction.

Methods, processes, systems, devices and apparatus are provided for additive manufacture resulting in the 3D printing of ceramic materials and components with a thickness greater than three millimeters (3 mm). A sulfur-free 3D printable formulation comprises a liquid inorganic polymer resin using Stereolithograpy (SLA) printers and Digital Light Processing (DLP) curing of the polymer resin via the chemical bonding of the materials rather than sintering. Thus, the process has shorter manufacturing intervals, significantly lower energy use and produces larger scale ceramic components having less linear shrinkage, less mass loss and high ceramic yield with no corrosive sulfur compounds present in the ceramic component.

A composition includes granules in which zirconia particles are aggregated. The granules have an average circularity of 0.81 or greater based on a projected image.

A process for the preparation of a sterilized ceramic body including or essentially consisting of stabilized zirconia of a defined colour, including the steps of: providing a ceramic primary body including or essentially consisting of stabilized zirconia of a first colour A, and sterilizing the primary body using radiation sterilization whereby the primary body undergoes a colour change to a colour B. The process includes the further step of irradiating the sterilized primary body with electromagnetic radiation of at least one wavelength lying in the wavelength band ranging from 150 nm to 700 nm to induce an at least partial reversal of the colour change to obtain a colour C of the sterilized ceramic body, the colour C complying with the following requirements in the CIELAB colour space: L* being from 54 to 95, a* being from −15 to 15 and b* being from −15 to 15.