Abstract: A fluorine compound-containing composite material consists essentially of a metal or polymer matrix and particles or fibers of a polytetrafluoroethylene oligomer having a number average molecular weight of 10,000 or less, the proportion of the number of fluorine atoms to the number of the total atoms at the surface portion of the composite material being 40% or more.

Abstract: A molded article of fluorine-containing polymer, especially of polytetrafluoroethylene, with increased water-repellency, and a jig for holding articles to be washed during washing processes using an aqueous washing medium. The molded article with superior water-repellency can be obtained by a treatment of the surface of fluorine-containing polymer with a fluorine-containing gas after roughening of the surface. The water-repellent jig made of the surface treated polytetrafluoroethylene is suited for use as a carrier for washing semi-conductor wafers and glass plates or guide rolls of a liquid crystal display device.

Abstract: A fluorine compound-containing composite material consists essentially of a metal or polymer matrix and particles or fibers of a polytetrafluoroethylene oligomer having a number average molecular weight of 10,000 or less, the proportion of the number of fluorine atoms to the number of the total atoms at the surface portion of the composite material being 40% or more.

Abstract: The present invention provides a recording material containing a carbonaceous powder whose surfaces are modified with a fluorine gas. Even when the recording material of the present invention is stored for a long period of time, a carbonaceous powder such as a graphite powder or carbon black neither coheres nor precipitates. For example, even if the recording material of the present invention is used in a felt pen or a ball-point pen, the carbonaceous powder does not cohere in the container or the pen point, and therefore any clogging does not occur in the pen point and good writing is possible.

Abstract: The present invention provides a method of reducing the fluid friction drag of ships and fluid transport channels and prevent contamination and corrosion of a structure having an immersed portion. The method of forming an air layer over an immersed surface of a structure having an immersed portion, comprising the steps of: covering the immersed surface of a structure (hull 1) having an immersed portion with a coating layer 3, which has depressions 6 and projections 7 at the surface thereof and which has at least vertices 7' of the projections 7 formed of a water-repellent material 8; and supplying air a to the surface 10 of the coating layer to form an air film 12 between the coating surface 10 and water 13.

Abstract: The present invention provides a recording material containing a carbonaceous powder whose surfaces are modified with a fluorine gas. Even when the recording material of the present invention is stored for a long period of time, a carbonaceous powder such as a graphite powder or carbon black neither coheres nor precipitates. For example, even if the recording material of the present invention is used in a felt pen or a ball-point pen, the carbonaceous powder does not cohere in the container or the pen point, and therefore any clogging does not occur in the pen point and good writing is possible.

Abstract: A carbon electrode is disclosed comprising a porous carbon block and having a flexural strength of at least 50 MPa and exhibiting, on a linear sweep voltammogram obtained by subjecting the carbon electrode to potential sweep in concentrated sulfuric acid at 25.degree. C., a peak having a maximum current density at a potential of at level 1.2 V. This carbon electrode is substantially free from the danger of destruction and the danger of local breakage and partial coming-off and can advantageously be used as an anode not only for stably conducting the electrolysis of an HF-containing molten salt but also for producing a desired electrolysis product with high purity.

Abstract: In oxide film removing equipment for removing a SiO.sub.2 film on a semiconductor substrate by using hydrogen fluoride, a liquid mixture of hydrogen fluoride and methyl alcohol is prepared in a chemical factory beforehand. The liquid mixture of hydrogen fluoride and methyl alcohol is heated to generate azeotropic vapor at a semiconductor works and the vapor is used to remove the SiO.sub.2 film on the substrate. The liquid mixture of hydrogen fluoride and methyl alcohol previously prepared in the chemical factory increases safety during an operation at the semiconductor works.

Abstract: Disclosed is a carbon electrode having low polarizability, comprising a porous carbon block and, contained in the pores thereof, a metal fluoride mixture composed of LiF and a metal fluoride other than LiF. This carbon electrode can easily be obtained by a skillful impregnation method. When such a carbon electrode is used as an anode in electrolyzing an electrolyte comprising a mixed molten salt system of potassium fluoride and hydrogen fluoride in an electrolytic cell, polarization of the anode is extremely low and the anode effect is remarkably suppressed so that the electrolysis can stably be performed while exhibiting not only a high anodic current density but also a low voltage.

Abstract: A method for removing a film on a silicon layer formed on a surface of a substrate includes the steps of: (a) placing a substrate in a reaction chamber to be isolated hermetically from the outside air, and (b) feeding anhydrous hydrogen fluoride and alcohol simultaneously into the reaction chamber. Preferably, the method further includes the step of feeding only alcohol into the reaction chamber prior to and/or subsequent to the step (b). An alcohol layer is formed on the substrate surface, whereby the film can be removed uniformly by anhydrous hydrogen fluoride. A by-product of the reaction is taken out from the system of reaction by means of the alcohol on the substrate. No by-product remains on the substrate after the reaction. Since the silicon layer after the reaction is covered with alcohol, re-growth of a native oxide film thereon is also suppressed and on ionic contamination such as fluorine remains on the substrate surface.

Abstract: A carbon fluoride comprising carbon atoms and fluorine atoms and having a structure in which layers containing fluorinated condensed cyclohexane rings are stacked to form a packing structure, the atomic ratio of fluorine to carbon atoms being 0.5 to 1.8, the carbon fluoride exhibiting a powder X-ray diffraction pattern in which there are peaks respectively at about 13.degree. (2.theta.) and at about 40.degree. (2.theta.) and no peak on the low side of diffraction angle relative to 13.degree. (2.theta.) and exhibiting a spectrum of electron spectroscopy for chemical analysis in which there are peaks respectively due to a monofluorocarbon group and due to a difluorocarbon group, the intensity ratio of the peak due to the difluorocarbon group to the peak due to the monofluorocarbon group being 0.15 to 1.5. The carbon fluoride has a unique property that it is capable of forming a film by vacuum deposition. The carbon fluoride may be produced by the direct fluorination of a pitch or meso-carbon microbeads.

Abstract: Process for electrolytically producing metals of Ni, Co, Zn, Cu, Mn, and Cr, comprising, electrolyzing an aqueous solution containing ions of a metal as main component selected from Ni, Co, Zn, Cu, Mn, and Cr in a cathode compartment to deposit the metal electrolytically on a cathode, the cathode compartment being separated by one or more diaphragms from the remainder of the solution where iron or a metal containing iron is used for material of corrosible anode, and maintaining the concentration of iron ion in the solution circulating in the anode compartment at a low level by bringing the whole or a part of the circulating solution into contact with an organic solvent which is prepared by adding petroleum hydrocarbon for dilution of one or more extracting agents selected from the group consisting of carboxylic acids, alkylaryl phosphoric acids, hydroxyoximes, alkyl phosphoric acids, alkylamines, ketones, alkylamides, and neutral phosphoric acid esters, to extract and remove the iron or the chloro-complex ion

Abstract: There is disclosed a hollow fiber semipermeable membrane element comprising hollow fiber semipermeable membranes having their respective one end portions or both end portions bonded together by means of a vulcanized rubber, so that the semipermeable membrane element has a high resistance to chemicals. The incorporation of a graphite fluoride in the rubber serves to further increase not only the hardness of the bonding rubber portions but also the resistance of the bonding rubber portions to chemicals. Such a semipermeable element can be easily, efficiently produced on a commercial scale.

Abstract: There is disclosed a method for producing a graphite fluoride for use in an electrochemical cell of the type having as the negative electrode a light metal, such as an alkali metal, an electrolyte in which the negative electrode is not dissolved, and a positive electrode which has, as an active material, a graphite fluoride produced by fluorinating a decomposition residual carbon which has been obtained by decomposing a covalent intercalation compound. The electrochemical cell of the present invention exhibits high discharge potential and low overvoltage, and excellent discharge characteristics with respect to the flatness of discharge voltage, discharge capacity and shelf-life.

Abstract: A crystallizer comprising a mixing zone of an organic solvent containing ions of a metal extracted therein and an aqueous separating solution provided at the upper part of a main crystallizer body, a lower-part opened organic solvent settling zone provided outside of the mixing zone for receiving and settling the organic solvent overflowing out of the mixing zone, a crystals developing zone having a downwardly narrowing cross section provided at the lower part of the main crystallizer body, a descending pipe extending from the lower end of the mixing zone to the lower part of the crystals developing zone, a crystals fluidizing medium inlet provided at the lower end of the crystals developing zone, a separating solution discharge pipe and a crystals discharge pipe.

Abstract: A novel ternary intercalation compound of a graphite with an alkali metal fluoride and fluorine, which is represented by the formula C.sub.x F(MF).sub.y wherein M is an alkali metal is produced by reacting a graphite material with an alkali metal fluoride in an atmosphere of fluorine gas at a temperature of 0.degree. C. to 250.degree. C. for at least a period of time to effect a weight increase in the graphite. The ternary graphite intercalation compound thus obtained has not only an excellent stability to humidity or moisture but also a high electrical conductivity. The novel ternary graphite intercalation compound according to the present invention may be practically used as a novel electrically conductive material and a catalyst of organic reactions.

Abstract: A novel ternary intercalation compound of a graphite with a metal fluoride and fluorine, which is represented by the formula C.sub.x F(MF.sub.z).sub.y wherein M is a metal is produced by reacting a graphite material with a metal fluoride in an atmosphere of fluorine gas at a temperature of 0.degree. C. to 400.degree. C. for at least a period of time to effect a weight increase in the graphite. The ternary graphite intercalation compound thus obtained has not only an excellent stability to humidity or moisture but also a high electrical conductivity. The novel ternary graphite intercalation compound according to the present invention may be practically used as a novel electrically conductive material and a catalyst of organic reactions.

Abstract: A novel ternary intercalation compound of a graphite with a metal fluoride and fluorine, which is represented by the formula C.sub.x F(MF.sub.z).sub.y wherein M is Al or Mg and z is an integer corresponding to the valence of M, is produced by contacting a graphite material with a metal fluoride selected from AlF.sub.3 and MgF.sub.2 in an atmosphere of fluorine gas at a temperature of 0.degree. C. to 400.degree. C. for at least a period of time to effect a weight increase in the graphite. The ternary graphite intercalation compound thus obtained has not only an excellent stability to humidity or moisture but also a high electrical conductivity. The novel ternary graphite intercalation compound according to the present invention may be practically used as a novel electrically conductive material and a catalyst of organic reactions.

Abstract: A graphite fluoride comprising mainly poly-dicarbon monofluoride represented by the formula (C.sub.2 F).sub.n can be produced in an extremely short period of time by a process comprising reacting a graphite material with fluorine in the presence of a specific fluoride.

Abstract: A process for preparing high purity superfine powders of less than 0.5.mu. diameter of Mo, W, Nb, Zr, Cu, Zn, Co, Ni and In by first producing their fluoride or a double fluoride with ammonium and then decomposing them under heat in a hydrogen-containing stream. Features of the present process are that the double fluoride of the metals with ammonium is faster in crystal growth than their fluoride, recrystallization of these salts can be repeated as desired when a high purity of the metals is required, and particles of a uniform size can be obtained easier.