The invention relates to the use of lithium silicate glass ceramics and glasses with caesium oxide content, which are suitable in particular for veneering oxide ceramic restorations and metal restorations.

A glass glass-ceramic composite comprises a substrate comprising an alkali-containing glass bulk, the bulk comprising Al.sub.2O.sub.3 and SiO.sub.2 and alkali, and a glass-ceramic surface layer, the surface layer comprising an alkali-depleted glass ceramic comprising Al.sub.2O.sub.3 and SiO.sub.2 with at least 5% crystalline phase by volume, wherein the alkali-depleted glass ceramic surface layer comprises a mol % Al.sub.2O.sub.3 of at least 51%. A method of preparing the composite is also disclosed.

The present invention provides a microcrystalline glass product. The microcrystalline glass product includes the following components in percentage by weight: SiO.sub.2: 45-70%; Al.sub.2O.sub.3: 8-18%; Li.sub.2O: 10-25%; ZrO.sub.2: 5-15%; P.sub.2O.sub.5: 2-10%; and Y.sub.2O.sub.3: greater than 0 but less than or equal to 8%. Through reasonable component design, the microcrystalline glass and the microcrystalline glass product obtained in the present invention have excellent mechanical and optical properties and are suitable for electronic devices or display devices.

Lithium silicate materials are described which can be easily processed by machining to dental products without undue wear of the tools.

A pre-sintered porcelain block for dental restoration; the pre-sintered porcelain block does not contain crystal phases and has a Vickers hardness of 0.5-2 GPa. Due to a hardness which is significantly lower than that of the porcelain block containing a lithium metasilicate crystal phase, the pre-sintered porcelain block may be processed by using dry machining and can simultaneously be processed by using wet machining when being mechanically processed into a dental restoration shape.

A fitout article or article of equipment for a kitchen or laboratory is provided. The article has a lighting and separating element. The separating element in a region of the lighting element has light transmittance of at least 0.1% and less than 12%. The lighting element in the interior emits light that passes through the separating element and to the exterior. The separating element has a glass or glass-ceramic substrate having a CTE of −6 to 6 ppm/K and has a colour locus in the CIELAB colour space with the coordinates L* of 20 to 40, a* of −6 to 6 and b* of −6 to 6. D65 standard illuminant light, after passing through the separating element, is within a white region W1 determined in the chromaticity diagram CIExyY−2° by the following coordinates: TABLE-US-00001 White region W1 x y 0.27 0.21 0.22 0.25 0.32 0.37 0.45 0.45 0.47 0.34 0.36  0.29.

A glass-ceramic, includes a silicate-containing glass comprising a first portion and a second portion. A plurality of crystalline precipitates comprising at least one of W and Mo. The crystalline precipitates are distributed within at least one of the first and second portions of the silicate-containing glass. The glass-ceramic comprises a difference in absorbance between the first and second portions of 0.04 optical density (OD)/mm or greater over a wavelength range of from 400 nm to 1500 nm.

The present invention relates to glass-ceramic/silver composite precursor compositions in the form of powders, and to glass-ceramics/silver composite materials produced therefrom. Such materials find particular use as interconnect materials for high temperature electrochemical conversion devices such as solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs).

Disclosed is a pre-sintered ceramic block for a dental restoration, which has a low pre-sintering temperature, contains a silica main crystal phase, but does not contain or contains a small amount of lithium metasilicate crystal phase. The pre-sintered ceramic block has a low hardness, with a Vickers hardness of 0.5-3 GPa, which is significantly lower than that of a ceramic block containing a lithium metasilicate crystal phase, and same is suitable for dry machining and also wet machining when being machined into a dental restoration. (FIG. 2)

The present application provides transparent glass-ceramics of β-quartz of composition containing a small content of lithium, articles constituted at least in part of said glass-ceramics, glasses precursors of said glass-ceramics, and also a method of preparing said articles. Said glass-ceramics have a composition, free of arsenic oxide and antimony oxide, except for inevitable traces, expressed as percentages by weight of oxides, containing: 62% to 68% of SiO.sub.2; 17% to 21% of AI.sub.2O.sub.3; 1% to <2% of Li.sub.2O; 1% to 4% of MgO; 1% to 6% of ZnO; 0 to 4% of BaO; 0 to 4% of SrO; 0 to 1% of CaO; 1% to 5% of TiO.sub.2; 0 to 2% of ZrO.sub.2; 0 to 1% of Na.sub.2O; 0 to 1% of K.sub.2O; with Na.sub.2O+K.sub.2O+BaO+SrO+CaO<6%; optionally up to 2% of at least one fining agent comprising SnO.sub.2; and optionally up to 2% of at least one coloring agent.