Abstract: A transparent colored glass ceramic, in particular an LAS glass ceramic, suitable for use as a cooking surface is provided. The transparent colored glass ceramic includes high-quartz solid solution (HQ s.s.) as a main crystal phase and exhibits thermal expansion of ?1 to +1 ppm/K in the range from 20° C. to 700° C. The glass ceramic has from 3.0 to 3.6 percent by weight of lithium oxide (Li2O) as constituents and either is colored with 0.003 to 0.05 percent by weight of vanadium oxide (V2O5) or is colored with 0.003 to 0.25 percent by weight of molybdenum oxide (MoO3).

Abstract: A glass ceramic article is provided so that a reliable coloring with a defined transmittance is ensured. The reliable coloring of the glass ceramic article is based on a high content of iron oxide of more than 0.1 percent by weight which itself has a strongly coloring effect does not further reduce transmittance but rather interacts with vanadium oxide to attenuate the absorption caused by vanadium oxide.

Abstract: A description is given of a coloured, transparent, lithium aluminium silicate glass-ceramic and also of the use thereof, said glass-ceramic possessing a light transmission Y of 2.5% to 10% and a spectral transmission ?(at 465 nm) of more than 1.0%.

Abstract: A glass ceramic substrate made of a transparent, colored LAS glass ceramic is provided. The glass ceramic has a gradient layer with keatite solid solution and an underlying core with high-quartz solid solution as predominant crystal phase. The keatite solid solution in a depth of 10 ?m or greater exceeds 50% of the sum of the high-quartz solid solution proportion and keatite solid solution proportion. The ceramization includes a crystal transformation step, in which the high-quartz solid solution is transformed at a maximum temperature in the range of 910° to 980° and a time period of between 1 and 25 minutes in part into the keatite solid solution.

Abstract: A glass-ceramic cooktop is provided that is made of glass-ceramic material with a flat upper side and an underside. The glass-ceramic material has transmittance values of greater than 0.1% in the visible light range in the total wavelength region greater than 420 nm, a light transmittance in the visible range of 0.8-2.5%, and a transmittance of 0-85% in the infrared at 1600 nm, and wherein the glass-ceramic material has high quartz mixed crystals as the prevalent crystal phase. The underside is flat, unstructured, and coplanar with the upper side.

Abstract: An LAS-glass for producing a transparent glass-ceramic and an LAS-glass-ceramic having a predetermined chroma C* and a predetermined visually determinable scatter value (S) are provided. The LAS-glass and LAS-glass-ceramic has a process window as large as possible during the nucleus formation process with respect to the residence time in the relevant temperature range for the formation of nuclei.

Abstract: A glass-ceramic cooktop is provided that is made of glass-ceramic material with a flat upper side and an underside. The glass-ceramic material has transmittance values of greater than 0.1% in the visible light range in the total wavelength region greater than 420 nm, a light transmittance in the visible range of 0.8-2.5%, and a transmittance of 0-85% in the infrared at 1600 nm, and wherein the glass-ceramic material has high quartz mixed crystals as the prevalent crystal phase. The underside is flat, unstructured, and coplanar with the upper side.

Abstract: A cooktop with a graphical display device is provided. The cooktop includes a glass ceramic substrate with a dead-front effect in which lightness differences in the display area and in particular differences between the latter and the adjacent areas of the cooktop are not visible for a user from the exterior. The cooktop has a glass or glass ceramic substrate and a display device with a display surface for displaying information by emission of light, wherein the display device is in the interior of the cooktop or cooking appliance such that light emitted from the display surface passes through the glass or glass ceramic substrate and is perceptible by a user in the exterior.

Abstract: A method of manufacturing glass ceramic articles such as glass ceramic plates for cooktops or fireplace windows is provided. The method facilitates the adjustment of a specific hue or a specific absorptivity of the glass ceramic in the visible spectral range. The method is based on the finding that the absorption of light by coloring agents which are appropriate for or present in glass ceramics can be attenuated during the ceramization process by adding substances that have a decoloring effect.

Abstract: A cooktop is provided that has a glass ceramic cooking plate, at least one heater arranged below the glass ceramic cooking plate, and at least one touch sensor. The touch sensor is operable across the glass ceramic cooking plate for adjusting the power of the at least one heater. The glass ceramic cooking plate has an increased strength and is therefore produced with a reduced thickness, whereby the sensitivity and reliability of the touch sensor is significantly improved.

Abstract: A cooktop is provided that includes a glass ceramic cooking plate that exhibits enhanced mechanical strength and at the same time increased spectral transmittance in the infrared range. The glass ceramic cooking plate makes it possible to detect, through the glass ceramic cooking plate, the temperature of a piece of cookware placed thereon using an infrared sensor, and to perform an automated cooking process in response thereto.

Abstract: A method for producing bubble-free glasses is provided, in which a glass mixture that is arsenic-free, antimony-free and tin-free with the exception of any unavoidable raw material impurities and at least one sulfate compound as a refining agent are used. The glass mixture and refining agent are melted and primarily refined in a first region of a melting tank, an average melting temperature (T1) is set at T1>1580° C. and an average melt residence time (t1) is set at t1>2 hours. A secondary refinement is carried out in a second region, an average melting temperature (T2) is set at T2>1660° C. and an average melt residence time (t2) is set at t2>1 hour, and the proportion of the SO3 resulting from decomposition of the sulfate is reduced to less than 0.002 wt. %.

Abstract: A display device in particular for cooktops is provide that has a glass ceramic with a front side and a back side and a lamp arranged in the area of the back side. The display device further includes an optical compensation filter arranged between the front side and the lamp so as to implement any color impressions easily and inexpensively and in a preselectable manner.

Abstract: Transparent or transparent dyed lithium aluminum silicate (LAS) glass ceramic material is provided that has an adapted thermal expansion. The material includes high-quartz mixed crystals as the predominant crystalline phase, and a thermal expansion between room temperature and 700° C. from 1.0 to 2.5·10?6/K.

Abstract: A glass ceramic substrate made of a transparent, colored LAS glass ceramic is provided. The glass ceramic has a gradient layer with keatite solid solution and an underlying core with high-quartz solid solution as predominant crystal phase. The keatite solid solution in a depth of 10 ?m or greater exceeds 50% of the sum of the high-quartz solid solution proportion and keatite solid solution proportion. The ceramization includes a crystal transformation step, in which the high-quartz solid solution is transformed at a maximum temperature in the range of 910° to 980° and a time period of between 1 and 25 minutes in part into the keatite solid solution.

Abstract: An LAS-glass for producing a transparent glass-ceramic and an LAS-glass-ceramic having a predetermined chroma C* and a predetermined visually determinable scatter value (S) are provided. The LAS-glass and LAS-glass-ceramic has a process window as large as possible during the nucleus formation process with respect to the residence time in the relevant temperature range for the formation of nuclei.

Abstract: A highly crystalline transparent, translucent or opaque lithium aluminium silicate (LAS) glass-ceramic which has a proportion of residual glass phase of less than 20% by weight and also the use thereof is described.

Abstract: A transparent low-colour lithium aluminium silicate (LAS) glass ceramic and the use thereof are provided. The ceramic has an environmentally friendly composition with high-quartz mixed crystals as the main crystal phase. The glass ceramic contains the following components (in wt % on the basis of oxide): TiO2 1.6-<2.5; Nd2O3 0.005-0.15; MgO 0.2-1.0; ZnO 1-2.5; CaO+SrO 0-1.5; BaO 0-1.5 with the condition B1: MgO+ZnO>CaO+SrO +BaO. In some embodiments, the glass ceramic has a hue c* of less than 5.5, a light transmission Y greater than 81% and has no visually disruptive diffusion.

Abstract: A product is provided that includes a volume-colored monolithic glass or glass ceramic element and to a method for producing same. The glass or glass ceramic element has a first region in which the coloration is modified so that light transmission of the first region differs from light transmission of a second, adjacent region. The light scattering in the region of modified coloration in the glass or glass ceramic remains the same as light scattering in the second, adjacent region with non-modified light transmission.

Abstract: A glass ceramic as cooktop for induction heating having improved colored display capability and heat shielding is provided. The cooktop includes a transparent, dyed glass ceramic plate having high-quartz mixed crystals as a predominant crystal phase. The glass ceramic contains none of the chemical refining agents arsenic oxide and/or antimony oxide and has a transmittance values greater than 0.4% at at least one wavelength in the blue spectrum between 380 and 500 nm, a transmittance >2% at 630 nm, a transmittance of less than 45% at 1600 nm, and a light transmittance of less than 2.5% in the visible spectrum.