Abstract: A heat insulating molded body made of inorganic material and inorganic reinforcement fibers is disclosed, as well as a process for producing the same and its use. The molded body is characterized by the following composition: (a) 30-70 wt. % blown vermiculite; (b) 15-40 wt. % inorganic binder; (c) 0-20 wt. % infrared opacifier; (d) 15-50 wt. % microporous material; (e) 0.5-8 wt. % reinforcement fibers which contain maximum 2 wt. % B2O3 and at most 2% alkalimetal oxide, based on the weight of the reinforcing fibers.

Abstract: The invention relates to a panel-shaped, evacuated and thermally insulating molded element which contains pressed and optionally hardened, microporous insulating material, wherein the insulating material is in one or more sheathed and evacuated layers, and the molded element has a surface with a lamellar structure, the lamellae being produced by elongate incisions into the surface and having a depth of 40 to 95% of the thickness of the molded element. The invention also relates to a method of insulation for curved surfaces with thermally insulating material, wherein the molded element is made to fit with the surface with a lamellar structure snugly against the curved surface, is fixed in position, and the vacuum is destroyed in at least one layer.

Abstract: The invention relates to a mixture for producing a heat-insulating molding, comprising from 20% to 99% by weight of microporous, oxidic inorganic material, from 0% to 50% by weight of opacifier, from 0% to 50% by weight of fiber material and from 0% to 15% by weight of inorganic binding material, and from 1% to 20% of a combustible component which on heat treatment burns with virtually no residue leaving behind pores in the finished molding. The invention also relates to a process for producing the molding.

Abstract: A process for the production of a microporous body having heat insulation properties by(a) mixing of(I) 0.5%-60% by weight of at least one compound selected from the group consisting of magnesium carbonate/calcium carbonate, and magnesium carbonate/calcium hydroxide(II) 5%-95% by weight of highly dispersed SiO.sub.2 with a content of 0%-20% by weight of Al.sub.2 O.sub.3 (based on the SiO.sub.2 employed);(III) 0%-60% by weight of an opacifying agent having at least one absorption maximum in the wavelength range of 1.5-10 .mu.m; and(IV) 0.1%-10% by weight of an organic fiber selected from the group consisting of cellulose fibers and carbon fibers;(b) compressing the mixture prepared to form a shaped article; and(c) heating the shaped article under oxidizing conditions produced at a temperature between 750.degree. C. to 950.degree. C. to oxidize the organic fibers and to produce the microporous body.

Abstract: A radiant heater, in particular for heating a glass-ceramic hot plate, has an area bearing an electrical heating element, with this area being the surface of an insulator which comprises a mounting layer and/or a thermally insulating microporous insulation layer, and having a dish-shaped enclosure which forms an annulus surrounding the insulator. The radiant heater has the mounting layer and/or the enclosure and/or the microporous insulation layer comprising a highly porous, fiber-free inorganic material, for example vermiculite. A particularly preferred embodiment provides for a fiber-free radiant heater.

Abstract: A process for continuously rendering finely divided, pyrogenic silica hydrophobic at low temperatures in the presence of a hydrophobicizing aid such as aliphatic alcohols having from 1 to 3 carbon atoms. The process of rendering silica hydrophobic is conducted at temperatures of from 60.degree. to 350.degree. C., and more preferably from 80.degree. to 150.degree. C., over a period of from 2 to 5 hours, and more preferably from 3 to 4 hours. The hydrophobicizing agents are known organohalosilanes and the preferred hydrophobicizing aid is methanol. The hydrophobicizing aid is used in amounts of from 2% to 15% by weight, and more preferably in amounts of from 2% to 10% by weight, based on the weight of silica used.

Abstract: The invention relates to a process for continuously hydrophobicizing pyrogenic, finely divided silica, in which the waste gases are fed back to a mixing chamber upstream of the SiO.sub.2 reaction flame.

Abstract: A method for producing shaped heat-insulating bodies based on water-insoluble oxidic metal compounds particularly of the elements silicon and aluminum, clouding agents and other additives, whereby the bodies are thermally hardened and have a heat conductivity of 0.02 to 0.1 W/K.m at temperatures of approximately 300.degree. to 500.degree. C. and are comprised of (a) 100 parts by weight of water-insoluble oxidic metal compounds having a BET-surface of 10 to 700 m.sup.2 /g, with the provision that at least 5% by weight of these compounds have a BET-surface of at least 50m.sup.2 /g; (b) 0 to 100 parts by weight of mineral clouding agents having at least one absorption maximum in the wave length range of 1.5 to 10 .mu.m; and (c) 0.1 to 30 parts by weight of elements capable of forming a solid oxide having a standard formation enthalpy of less than minus 900 kJ/Mol. In addition, 0-100 parts by weight of mineral fibers can be added.

Abstract: A process for the preparation of an organohalosilane of the general formula:X.sub.4-n SiR.sub.nin which,R represents a methyl, ethyl, n-propylisopropyl, n-butyl, isobutyl, phenyl or a tolyl functional group;X represents chlorine or bromine; andn is 1, 2 or 3,is disclosed. The process takes place by reacting an SiO.sub.2 -containing material with a hydrocarbon halide of the general formula RX, in which R and X are defined as above. The reaction between the SiO.sub.2 -containing material and RX takes place in the presence of iron powder and either: (a) carbon and a catalyst, in which the SiO.sub.2 -containing material, the iron powder, the carbon and the catalyst are subjected to a heat treatment at 800.degree. to 1400.degree. C. prior to the reaction with RX or (b) an aluminum trihalide and/or boron trihalide in which the halogen is either chlorine or bromine. Alternative (b) may be carried out in the presence of a catalyst.

Abstract: A molded thermal insulation body having a microporous thermal insulation material encased in a sheathing. The molded body is partially evacuated to a partial air pressure of 20 mbar or less. Following the evacuation of air, the molded body may be filled with krypton, xenon, sulfur hexafluoride, carbon dioxide or a combination thereof. A process for the manufacture of the molded thermal insulation body is also provided.

Abstract: The invention relates to the preparation of silicon tetrachloride by reacting material containing SiO.sub.2 with chlorine in the presence of carbon and metal halides and especially chlorides of the fifth main or subsidiary group of the Periodic Table at temperatures in the range of from 500.degree. to 1200.degree. C. The material containing SiO.sub.2 has a BET surface area of at least 0.1 m.sup.2 /g and the carbon has a BET surface area of at least 0.5 m.sup.2 /g.

Abstract: A process for the production of pyrogenic silicic acid having an increased thickening effect which comprises subjecting silicon-containing materials to a pyrolysis flame while introducing additional energy into the flame. The invention also relates to the product so obtained, particularly useful for articles of dental care.

Abstract: The invention is an insulating plate capable of being bonded to a substrate comprising a highly disperse inorganic heat-insulating material and a binder, the binder being inhomogeneously distributed in such a manner that in the region near the bonding surface, the content of binder is from 3 to 15% by weight, and, in the remaining region, it is from about 0 to 1.5% by weight. The plate according to the invention may be in the form of a cooking plate.

Abstract: The invention relates to a heat-insulating board which has a core and a cover. The core is composed of compacted, finely particulate metal oxide and, optionally, additions of opacifier and fibrous material. The cover is composed in part of metal foil arranged on those faces that are to be directed against the heat flow. The remainder of the cover is composed of a material that inhibits heat flow. A method for manufacturing the board is also disclosed.

Abstract: A method for increasing the bulk weight of silicon dioxide with a surface of at least 50m.sup.2 /g by means of sub-atmospheric pressure applied at a filter face, wherein the silicon dioxide is moved by means of a conveyor screw, whose longitudinal axis is arranged parallel with respect to the filter face and which preferably has a decreasing thread pitch in feeding direction. Furthermore, the invention relates to the use of the treated silicon dioxide as a filler material for polymeric masses, especially diorganopolysiloxane, which is storeable in the absence of water and when admixed with water at room temperature results in a hardened elastomer mass.

Abstract: This invention relates to compositions which may be stored under anhydrous conditions, but when exposed to atmospheric moisture, crosslink at room temperature to form elastomers. These compositions contain diorganopolysiloxanes having terminal condensable groups, a silicon compound having at least 3 Si-bonded hydrolyzable groups and an inorganic filler having a surface area of at least 20 m.sup.2 /g, in which at least a portion of the surface area of the inorganic filler has been modified by having polymerized thereon at least one compound of the general formulaHR.sup.1 C.dbd.CHX,where X represents a --CN group or a group of the formula --COOR.sup.2, R.sup.2 is an alkyl radical having from 1 to 4 carbon atoms and R.sup.1 represents hydrogen or a methyl group; or a mixture containing at least one such compound and at least one monomer which has been copolymerized with said compound.

Abstract: An agglomerated mixture includes 30-95% by weight of highly dispersed metal oxides produced by flame hydrolysis and 5-70% by weight of inorganic opacifiers that have at least one absorption maximum in the range between 1.5 and 10 .mu.m, selected from the group consisting of inorganic oxides and mixed oxides, carbides and nitrides. The invention also relates to a process of manufacturing the mixtures and to their use as heat-insulating material and the like.

Abstract: This invention relates to a process for improving heat insulating articles containing silicon dioxide having a surface area of at least 50 m.sup.2 /g, opacifiers and, if desired, inorganic fibers which comprises treating the surface of the insulating articles with at least one organosilicon compound containing from 1 to 4 silicon atoms to render the same hydrophobic.

Abstract: This invention relates to a process for preparing hydrophobic silicon dioxide which comprises treating silicon dioxide having a surface area of at least 50 m.sup.2 /g with an organosilicon compound containing from 2 to 4 silicon atoms per molecule, in which at least 2 hydrocarbon radicals are bonded to each silicon atom, and any silicon valences which are not satisfied by hydrocarbon radicals are satisfied by siloxane oxygen atoms and at least one tin compound containing Sn-bonded halogen and/or organic radicals.

Abstract: A process for the manufacture of highly dispersed silicon dioxide with improved thickening action by treatment of pyrogenically produced silicic acid comprising the following steps:A. preparing silicic acid by flame hydrolysis from silicon halides;B. separating the silicic acid from generated gases;C. reating the acid with 2 to 10 percent by weight of silicon tetrachloride calculated on silicic acid, while optionally/mechanically stirring;D. hydrolyzing the product by means of an air/water vapor mixture, and finally deacifying to obtain the silicon dioxide of improved thickening action.The invention also relates to the thickening agent, which is useful for a variety of purposes, among others as additive for preparations of dental hygiene.