Abstract: The method of environmentally friendly melting and refining a glass melt of a crystallizable glass, which is used for making a lithium aluminum silicate (LAS) glass ceramic, includes the steps of providing a glass batch with a main batch composition within a lithium aluminum silicate (LAS) glass system, in which 0.1-<0.6% by weight of tin oxide has been added as main refining agent, but which does not contain arsenic oxide and/or antimony oxide as refining agent, formulating a raw material mixture for the glass batch, so that less than 40% by weight of the raw material mixture is quartz sand and then refining a glass melt formed from the glass batch at temperatures of at least 1600° C.

Abstract: The method produces a reshaped glass-ceramic article by forced reshaping of a flat green glass part during a ceramicizing process with temporarily lowered viscosity due to crystallization heat. To perform the forced reshaping economically the forced reshaping takes place in a continuous oven for ceramicizing and in an oven section in which the viscosity of the green glass part is temporarily lowered as a result of crystallization heat. An apparatus for performing the process is provided in the continuous oven including different active reshaping devices and/or a hollow mold. The method produces glass-ceramic articles with undamaged surfaces corresponding to surfaces produced during the making of the green glass part (smooth or structured, e.g. knobbed).

Abstract: In the method of manufacturing a cooking stove its stove top can be equipped with different glass ceramic tops, which each have at least one cooking area, which is heated by a radiant heating body cooperating with a temperature-limiting adjusting device, which limits a surface temperature of the glass ceramic top. To economically and individually adjust the IR transmission of a glass ceramic top with a higher IR transmittance to that of a lower IR transmittance corresponding to that of another glass ceramic top so that they are interchangeable, the glass ceramic top with the higher IR transmittance is provided with an absorbing and/or reflecting coating. When the glass ceramic tops are interchangeable, either can be used in a given cooking stove without changing the expensive temperature-limiting device.

Abstract: The method of environmentally friendly melting and refining a glass melt of a crystallizable glass, which is used for making a lithium aluminium silicate (LAS) glass ceramic, includes the steps of providing a glass batch with a main batch composition within a lithium aluminium silicate (LAS) glass system, in which 0.1-<0.6% by weight of tin oxide has been added as main refining agent, but which does not contain arsenic oxide and/or antimony oxide as refining agent, formulating a raw material mixture for the glass batch, so that less than 40% by weight of the raw material mixture is quartz sand and then refining a glass melt formed from the glass batch at temperatures of at least 1600° C.

Abstract: The apparatus performs a forced reshaping of a flat green glass part during a ceramicizing process in which the viscosity of the glass is temporarily lowered due to crystallization heat. The apparatus includes a continuous furnace (3) for the ceramicizing process: a reshaping device (2?) provided with activating openings (6); and vertically movable pressure-operated reshaping tools (9) arranged in the reshaping device (2?). The furnace (3) is provided with lateral openings (4) for temporarily connecting activating lines (8) to the activating openings (6) of the reshaping device (2?) in a sealed manner in order to operate the reshaping tools (9) by supplying pressurized air to the reshaping device or by producing a low pressure in the reshaping device (2?).

Abstract: The glass ceramic or glass element that can be subjected to high thermal loads is decorated with a metallic colorant. The metallic colorant consists of a melted silicate and at least one effect pigment, which is included in a specified proportion in a melt of the silicate glass to form the metallic colorant. The at least one effect pigment is in the form of platelets of synthetic aluminum oxide (Al2O3) coated with at least one metal oxide. Preferably the at least one effect pigment is a XIRALLIC® high chroma sparkle pigment supplied commercially by Merck and the metallic colorant has a pigment content of from 1 to 30 wt. %.

Abstract: The method produces a reshaped glass-ceramic article by forced reshaping of a flat green glass part during a ceramicizing process with temporarily lowered viscosity due to crystallization heat. To perform the forced reshaping economically the forced reshaping takes place in a continuous oven for ceramicizing and in an oven section in which the viscosity of the green glass part is temporarily lowered as a result of crystallization heat. An apparatus for performing the process is provided in the continuous oven including different active reshaping devices and/or a hollow mold. The method produces glass-ceramic articles with undamaged surfaces corresponding to surfaces produced during the making of the green glass part (smooth or structured, e.g. knobbed).

Abstract: In the method of manufacturing a cooking stove its stove top can be equipped with different glass ceramic tops, which each have at least one cooking area, which is heated by a radiant heating body cooperating with a temperature-limiting adjusting device, which limits a surface temperature of the glass ceramic top. To economically and individually adjust the IR transmission of a glass ceramic top with a higher IR transmittance to that of a lower IR transmittance corresponding to that of another glass ceramic top so that they are interchangeable, the glass ceramic top with the higher IR transmittance is provided with an absorbing and/or reflecting coating. When the glass ceramic tops are interchangeable, either can be used in a given cooking stove without changing the expensive temperature-limiting device.

Abstract: The glass ceramic or glass element that can be subjected to high thermal loads is decorated with a metallic colorant. The metallic colorant consists of a melted silicate and at least one effect pigment, which is included in a specified proportion in a melt of the silicate glass to form the metallic colorant. The at least one effect pigment is in the form of platelets of synthetic aluminum oxide (Al2O3) coated with at least one metal oxide. Preferably the at least one effect pigment is a XIRALLIC® high chroma sparkle pigment supplied commercially by Merck and the metallic colorant has a pigment content of from 1 to 30 wt. %.

Abstract: The cooking stove top can be equipped with two different glass ceramic tops with different IR transmission spectra, which each have at least one cooking area, which is heated by a radiant heating body cooperating with a temperature-limiting adjusting device, which limits a surface temperature of the glass ceramic top installed in the cooking stove and/or the surroundings. To economically, variably, and individually adjust the IR transmission of one glass ceramic top with a higher IR transmittance to that of a lower IR transmittance of another glass ceramic top so that they are interchangeable, the glass ceramic top with the higher IR transmittance is provided with an absorbing and/or reflecting coating. When the glass ceramic tops are interchangeable, either can be used in a given cooking stove without changing an expensive temperature-limiting device that is designed for the cooking stove.

Abstract: The invention relates to a glass ceramic or glass body that can be subjected to great thermal loads and is decorated with a color based on a melted silicate containing effect pigments. In order to reduce the protective look provided by the decoration, the melted silicate contains special effect pigments at a predefined ratio, said special effect pigments producing a color-flopping effect on the decorated glass ceramic of glass body. The human brain is hardly able to perceive the traces of wear as the tint changes according to the angle of vision. Preferably, the color-flopping color is based on a melted silicate to which effect pigments are added at a given ratio in the form of synthetic plane-parallel silicon dioxide (SiO2) laminae which are coated with metal oxides.

Abstract: The method produces a glass-ceramic article substantially in the form of a plate with improved high temperature difference resistance or strength. The glass-ceramic article contains keatite mixed crystals (KMK) or high quartz mixed crystals (HQMK) as well as the keatite mixed crystals (KMK). The method includes heating a glass-ceramic in a high quartz mixed crystal state to form the keatite mixed crystals with a heating rate of 20 K/min to 150 K/min, preferably more than 15 K/min, especially preferably more than 20 K/min. These high heating rates increase the temperature difference resistance.

Abstract: The translucent or opaque colored glass-ceramic article provides a cooking surface and has an adjustable light transmission in a visible range under 15%, as measured for a 4 mm sample thickness; a flaw-free upper surface with an impact resistance of greater than 18 cm breaking height, as tested with a 200 g steel ball in a falling ball test; a temperature difference resistance of greater than 500° C.; a high crystallinity with keatite mixed crystals as principal crystal phase in an interior of the glass-ceramic article and with a residual glass phase fraction of less than 8% by weight; a glassy upper surface layer of from 0.5 to 2.5 ?m thick, which is substantially free of high quartz mixed crystals and which inhibits chemical reactions, and a content of enriched ingredients in the residual glass phase in the interior of the glass-ceramic and in the glassy surface layer of ?Na2O+K2O+CaO+SrO+BaO+F+refining agents of from 0.2 to 1.6% by weight.

Abstract: The method produces a glass-ceramic article substantially in the form of a plate with improved high temperature difference resistance or strength. The glass-ceramic article contains keatite mixed crystals (KMK) or high quartz mixed crystals (HQMK) as well as the keatite mixed crystals (KMK). The method includes heating a glass-ceramic in a high quartz mixed crystal state to form the keatite mixed crystals with a heating rate of 20 K/min to 150 K/min, preferably more than 15 K/min, especially preferably more than 20 K/min. These high heating rates increase the temperature difference resistance.

Abstract: The method produces a reshaped glass-ceramic article by forced reshaping of a flat green glass part during a ceramicizing process with temporarily lowered viscosity due to crystallization heat. To perform the forced reshaping economically the forced reshaping takes place in a continuous oven for ceramicizing and in an oven section in which the viscosity of the green glass part is temporarily lowered as a result of crystallization heat. An apparatus for performing the process is provided in the continuous oven including different active reshaping devices and/or a hollow mold. The method produces glass-ceramic articles with undamaged surfaces corresponding to surfaces produced during the making of the green glass part (smooth or structured, e.g. knobbed).

Abstract: Stove or grill having a cook top, hob or cooking surface for cooking food. The cook top or hob is made of a glass ceramic material. The top surface of the cook top or hob has at least one groove-shaped depression to define and separate various zone and cooking areas on the cook top or hob.

Abstract: Stove or grill having a cook top, hob or cooking surface for cooking food. The cook top or hob is made of a glass ceramic material. The top surface of the cook top or hob has at least one groove-shaped depression to define and separate various zone and cooking areas on the cook top or hob.