Abstract: Hydrogen fluoride is effectively removed from a mixture of hydrogen fluoride, dichloromethane, chlorofluoromethane and/or difluoromethane by distilling the mixture so that two-component azeotropic mixtures of hydrogen fluoride and dichloromethane, hydrogen fluoride and chlorofluoromethane and hydrogen fluoride and difluoromethane are removed, or by liquid-separating the mixture into an upper liquid phase rich in hydrogen fluoride and a lower liquid phase not rich in hydrogen fluoride before each liquid phase is distilled as described above.

Abstract: A fluorination catalyst comprising chromium oxide having a specific surface area of from 170 m2/g to 300 m2/g, which can catalyze the fluorination of a halogenated hydrocarbon with hydrogen fluoride and has a high activity and a long catalyst life.

Abstract: An electronic document filing method and a system using the same is disclosed. The system comprises identification code addition means for adding identification code proper to the electronic document thereto, electronic document transfer means for registering the electronic document to which the identification code is added to the document server, print means for printing the registered electronic document and the identification code on the same paper face, identification code read means for reading the identification code printed on the paper face, identification code interpretation means for interpreting the identification code read by the identification code read means, and identification code transfer means for transferring the identification code interpreted by the identification code interpretation means to the document server.

Abstract: Azole compounds of the formula: wherein R1 is lower alkyl substituted with carboxy, etc., R2 is hydrogen or lower alkyl, R3 is aryl, etc. R4 is aryl, etc. Q is  etc., and X is O, NH or S, and its salt, which are useful as medicament.

Abstract: A halogenated hydrocarbon is effectively fluorinated by reacting the halogenated hydrocarbon with hydrogen fluoride in the presence of a fluorination catalyst which comprises a partially fluorinated chromium oxide containing at least one metal selected from the group consisting of ruthenium and platinum.

Abstract: At least one halogenated compound selected from the group consisting of 1,1,1,4,4,4-hexafluoro-2,3-dichlorobutane, 1,1,1,4,4,4-hexafluoro-2-chloro-2-butene, 1,1,1,2,4,4,4-heptafluoro-2-butene and 1,1,1,2,2,4,4,4-octafluorobutane, is prepared by reacting 1,1,2,3,4,4-hexachloro-1,3-butadiene with hydrogen fluoride in a gas phase in the presence of a fluorinating catalyst. Desired products can be prepared commercially according to the present invention.

Abstract: According to the method for producing difluoromethane and 1,1,1,2-tetrafluoroethane, having the steps of:(1) reacting methylene chloride and 1,1,2-trichloroethylene with hydrogen fluoride in a vapor phase In the presence of a fluorinating catalyst and 1,1,1,2-tetrafluoroethane in a first reactor; and(2) reacting 1,1,1-trifluorochloroethane with hydrogen fluoride in a vapor phase in the presence of a fluorinating catalyst in a second reactor, and supplying the reaction mixture from the second reactor to the first reactor, HFC-32 can be obtained in high conversion and high selectivity by fluorinating HCC-30 using commonly a large (excess) amount of HF which is required for producing HFC-134a.

Abstract: A method for preparing a fluorination catalyst is disclosed, wherein the catalyst contains chromium oxide, has a specific surface area of from 170 m.sup.2 g to 300 m.sup.2 /g, catalyzes the fluorination of a halogenated hydrocarbon with hydrogen fluoride, and has a high activity and long catalyst life. The method includes mixing an aqueous solution of a chromium salt with aqueous ammonia to precipitate chromium hydroxide, drying the precipitated chromium hydroxide, sintering the dried chromium hydroxide, and fluorinating the sintered chromium hydroxide to obtain the chromium oxide catalyst.

Abstract: In order to stably retain an oxide-based melt consisting essentially of yttrium or a lanthanoid element, barium, copper and oxygen at a prescribed temperature with no impurity contamination thereby preparing a large oxide crystal of high quality from the melt, an oxide melt consisting essentially of yttrium or a lanthanoid element, barium, copper and oxygen is stored in a first crucible, which in turn is held in a second crucible. The first crucible is made of a material which is an oxide of at least one element forming the melt having a melting point higher by at least 10.degree. C. than a melt retention temperature and causing no structural phase transition up to a temperature higher by 10.degree. C. than the aforementioned prescribed temperature, with solubility of not more than 5 atomic percent with respect to the melt in a temperature range from the room temperature to a temperature higher by 10.degree. C. than the melt retention temperature.

Abstract: A new 3,3-dichloro-1,1,1,2,2,4,4,5,5,5-decafluoropentane as a precursor of alternatives of refrigerants, etc.A method to obtain the target products at high yield and high selectivity by reacting tetrafluoroethylene and difluorodichloromethane under the Lewis acid catalyst to produce the new compound and an economical method in a continuous reaction state.A production method of 1,1,1,2,2,4,4,5,5,5-decafluoropentane at high yield by reducing 3,3-dichloro-1,1,1,2,2,4,4,5,5,5-decafluoropentane.

Abstract: Hydrogen fluoride is effectively removed from a mixture of hydrogen fluoride, dichloromethane, chlorofluoromethane and/or difluoromethane by distilling the mixture so that two-component azeotropic mixtures of hydrogen fluoride and dichloromethane, hydrogen fluoride and chlorofluoromethane and hydrogen fluoride and difluoromethane are removed, or by liquid-separating the mixture into an upper liquid phase rich in hydrogen fluoride and a lower liquid phase not rich in hydrogen fluoride before each liquid phase is distilled as described above.

Abstract: In a process for preparing 1,1,1-trifluorochloroethane by reacting, in a gas phase, trichloroethylene and hydrogen fluoride, when the reactant gases are diluted with a gas which is inactive to the reaction, it is very easy to control a reaction temperature, and when a generated gas from the reaction of 1,1,1-trifluorochloroethane and hydrogen fluoride is used as a diluent gas, generation of 1,1-difluoroethylene is suppressed to a very low level while not influencing the reaction between trichloroethylene and hydrogen fluoride.

Abstract: A process for preparing 1,1-dichloro-2,2,2-trifluoroethane characterized in that 1,1,1-trichloro-2,2,2-trifluoroethane is reduced with hydrogen in the presence of a hydrogenating catalyst comprising platinum to which at least one metal selected from the group consisting of silver, copper, gold, tellurium, zinc, chromium, molybdenum and thallium is added.1,1-Dichoro-2,2,2-trifluoroethne can be obtained in a high yield.

Abstract: A process for preparing 1,1,1-trifluoro-2-chloroethane and/or 1,1,1,2-tetrafluoroethane, comprising the steps of reacting trichloroethylene and/or 1,1,1-trifluoro-2-chloroethane with hydrogen fluoride in the presence of a fluorinating catalyst in a gas pase, separating 1,1,1-trifluoro-2-chloroethane, hydrogen fluoride, and optionally trichloroethylene, from the reaction mixture obtained by the above reaction which contains 1,1,1-trifluoro-2-chloroethane, 1,1,1,2-tetrafluoroethane, hydrogen fluoride, and optionally trichloroethylene, and recycling them to the reaction step above, characterized in that at least a part of the reaction mixture is distilled in a distillation tower, 1,1,1,2-tetrafluoroethane-rich components are discharged from the top of the tower, and a mixture of 1,1,1-trifluoro-2-chloroethane and hydrogen fluoride, and optionally trichloroethylene, is discharged in the form of gas from the middle part of the tower at a temperature which is above the boiling point of the azeotropic mixture of 1,1

Abstract: Hydrogen fluoride and 1,1,1-trifluoro-2-chloroethane forms an azeotropic mixture of which molar ratio of HF/1,1,1-trifluoro-2-chloroethane varies, for example, from about 60/40 at a pressure of 1.5 Kg/cm.sup.2 G and a temperature of 20.degree. C. to about 45/55 at a pressure of 15 Kg/cm.sup.2 G and a temperature of 87.degree.C.

Abstract: In a process for preparing 1,1,1-trifluorochloroethane by reacting, in a gas phase, trichloroethylene and hydrogen fluoride, when the reactant gases are diluted with a gas which is inactive to the reaction, it is very easy to control a reaction temperature, and when a generated gas from the reaction of 1,1,1-trifluorochloroethane and hydrogen fluoride is used as a diluent gas, generation of 1,1-difluoroethylene is suppressed to a very low level while not influencing the reaction between trichloroethylene and hydrogen fluoride.

Abstract: 1,1,1,4,4,4-Hexafluorobutane is prepared by reducing 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 with hydrogen in the presence of a hydrogenation catalyst containing an alloy which contains at least one first metal component selected from the group consisting of platinum and palladium and at least one second metal component selected from the group consisting of silver, copper, gold, tellurium, zinc, chromium, molybdenum and thallium. 1,1,1,4,4,4-Hexafluorobutane can be prepared in a high selectivity and a high yield.

Abstract: A bismuth system oxide superconductor comprising the 110 K phase is effectively prepared by a process comprising the steps of mixing a bismuth compound, a strontium compound, a calcium compound, a copper compound and optionally a lead compound, optionally provisionally sintering the mixture, and sintering the mixture.

Abstract: In a process for preparing 1,1,1-trifluorochloroethane by reacting, in a gas phase, trichloroethylene and hydrogen fluoride, when the reactant gases are diluted with a gas which is inactive to the reaction, it is very easy to control a reaction temperature, and when a generated gas from the reaction of 1,1,1-trifluorochloroethane and hydrogen fluoride is used as a diluent gas, generation of 1,1-difluoroethylene is suppressed to a very low level while not influencing the reaction between trichloroethylene and hydrogen fluoride.

Abstract: A fluorinated compound of the formula:R--CCl.sub.2 CF.sub.2 CF.sub.3 (I)in which R is a perfluoroalkyl group, a perchloroalkyl group, a polyfluoroalkyl group, a polychloroalkyl group or a polychloropolyfluoroalkyl group, each having at least one carbon atom is prepared at a high selectivity and a high yield by reacting tetrafluoroethylene with a compound of the formula:R--CFCl.sub.2 (II)in which R is the same as defined above in the presence of a Lewis acid.