Abstract: A fluororubber composition according to the present invention contains 0.1 to 3 parts by weight of a polyol compound, 0.1 to 4 parts by weight of a peroxide crosslinking agent, and 1 to 9 parts by weight of a co-crosslinking agent per 100 parts by weight of a peroxide-crosslinkable fluoropolymer. A crack-resistant seal according to the present invention contains a crosslinked fluoropolymer and a polyol compound. The crack-resistant seal according to the present invention can be formed by crosslinking the fluororubber composition, and the resultant crack-resistant seal has particularly high crack resistance. With the fluororubber composition according to the present invention, a durable crack-resistant seal having high plasma resistance, crack resistance, and compression set and that produces few particles can be formed at low cost.

Abstract: When the composite sealing material is press-fitted, the swelled portion of the first sealing portion of a first sealing member is press-fitted to impart sealing ability, the second extended portion of a second sealing member is pressed to the opening portion side of a sealing groove through the first extended portion of the first sealing member, and the upper surface of the second sealing portion is press-fitted to impart sealing ability.

Abstract: A method forming a porous PTFE layer includes steps of: combining one or at least two unburned porous PTFE films and a support body that can withstand a heating condition in the following process (a rod or plate shaped support body made of mesh or the like is preferable) by using a predetermined means in such a manner that a slip can be prevented in a heating treatment in the following process; and heating the matter resulted from the above process at a temperature of at least 150° C. and less than the melting point of the PTFE film for the range of 5-120 minutes (preferably at a temperature in the range of the melting point of a thermoplastic resin fiber to 320° C. for the range of 10-60 minutes in the case in which the thermoplastic resin fiber or the like is used in the process.

Abstract: A method forming a porous PTFE layer includes steps of: combining one or at least two unburned porous PTFE films and a support body that can withstand a heating condition in the following process (a rod or plate shaped support body made of mesh or the like is preferable) by using a predetermined means in such a manner that a slip can be prevented in a heating treatment in the following process; and heating the matter resulted from the above process at a temperature of at least 150° C. and less than the melting point of the PTFE film for the range of 5-120 minutes (preferably at a temperature in the range of the melting point of a thermoplastic resin fiber to 320° C. for the range of 10-60 minutes in the case in which the thermoplastic resin fiber or the like is used in the process).

Abstract: A gate valve for vacuum capable of preventing a seal member from being cracked or particles from being produced due to a stress concentration even if the seal member is repeatedly compressed in the state that the adhesive agent is separated from the open side of a seal member mounting groove and capable of suppressing particles from being produced due to the rub of the seal top part with the seal surface.

Abstract: A process for producing a fluororesin sheet containing a filler includes a step of rolling a sheet-forming resin composition including a fluororesin, a filler and a processing aid at a roll temperature of from 40 to 80° C. The processing aid includes at least 30% by mass of a petroleum hydrocarbon solvent having a fractionating temperature of not higher than 120° C. based on 100% by mass of the amount of the processing aid. The fluororesin sheet so produced provides high stress relaxation properties along with high hermetic sealing properties even when the content of the fluororesin is low and the content of the filler is high.

Abstract: A composite sealing material to be installed in a sealing groove includes a first sealing member that is located on the outer peripheral side of the sealing groove and that is made of an elastic member; and a second sealing member that is located on the inner peripheral side of the sealing groove and that is made of a material harder than the first sealing member, wherein the first sealing member is provided with a crosswise protrusion formed projecting in a radial inner direction from a radial inner side of the almost central section of the thickness direction; the second sealing member is formed in an almost cross sectional C shape by flange portions and formed at the both ends and an inner wall portion in an almost linear shape for connecting the flange portions; and a space is ensured between the crosswise protrusion and the inner wall portion in an almost linear shape of the second sealing member in a state that the first sealing member and the second sealing member are assembled in an integrated manner.

Abstract: Method for producing at low cost bellows which show high durability even when used in a quite reactive atmosphere. A method for manufacturing bellows includes the steps of: I: forming an untreated bellows from a flat base plate, the base plate including 15 to 30 wt % of Cr, 5 to 40 wt % of Ni, 0.9 to 6 wt % of Al, less than 1 wt % of Mo, less than 0.1 wt % of Mn, less than 0.1 wt % of C, less than 0.1 wt % of S, less than 0.1 wt % of P and a balance of Fe and an unavoidable impurity (relative to 100 wt % of the base plate); and II: heating the untreated bellows at a temperature of 750 to 895° C. in an atmosphere which contains water and hydrogen and in which the volume ratio of hydrogen to water (H2/H2O) is in the range of 2×103 to 1×1012, thereby forming an Al2O3 passivation film on a surface of the untreated bellows.

Abstract: A sealing material for a semiconductor manufacturing apparatus includes as rubber components, 80 to 50% by weight of a tetrafluoroethylene-perfluoroalkylvinylether type perfluoro elastomer (FFKM) and 20 to 50% by weight of a fluoroelastomer (FKM) other than FFKM (where FFKM+FKM=100% by weight).

Abstract: A sealing material in a closed circular shape for a dovetail groove formed on the surface of one member and to be abutted to the surface of the other member to seal a space between the both members, the sealing material for a dovetail groove in a cross-sectional shape includes: a bottom portion that comes into contact with the bottom face of the dovetail groove and that has corner portions formed slightly narrower than the narrowest width of the opening portion of the dovetail groove; a side protruding portion that is formed continuously from the bottom portion; an overhanging shoulder portion that is formed continuously from the side protruding portion; and a sealing protrusion that is formed continuously from the overhanging shoulder portion and that is protruded upward from the opening portion of the dovetail groove to seal a space between the both members in the case in which the sealing protrusion is abutted to the surface of the other member.

Abstract: A low-compression force metal gasket includes a coating layer containing a polymer material on at least a sealing surface of the gasket, and the coating layer satisfies the following conditions (1) to (3): (1) the layer comprises a resin, a rubber or a mixture thereof having an oxygen gas permeability coefficient at 25° C. of 10×10?12 to 0.1×10?12 (m2/s); (2) when the layer is compression deformed, the storage elastic modulus (E?) at 200° C. is in the range of 1.0×107 to 1.0×102 Pa; and (3) the coating layer has a thickness of 1 to 40 ?m. The gasket provides a high seal at a low clamping force.

Abstract: A method forming a porous PTFE layer includes steps of: combining one or at least two unburned porous PTFE films and a support body that can withstand a heating condition in the following process (a rod or plate shaped support body made of mesh or the like is preferable) by using a predetermined means in such a manner that a slip can be prevented in a heating treatment in the following process; and heating the matter resulted from the above process at a temperature of at least 150° C. and less than the melting point of the PTFE film for the range of 5-120 minutes (preferably at a temperature in the range of the melting point of a thermoplastic resin fiber to 320° C. for the range of 10-60 minutes in the case in which the thermoplastic resin fiber or the like is used in the process.

Abstract: An object of the present invention is to make it possible to accurately and simply manage the performance deterioration and life duration of sealing rings and other various information about each sealing ring. As a means of achieving this object, a sealing ring according to the present invention is a sealing ring 30 to be fitted to a face-to-face part of members 12, 14 to thus seal a space between both members, comprising: a main body part 32 that is ring-shaped and is capable of becoming elastically deformed; and a circuit chip 40 that is attached unitedly to the main body part 32 and has an information-transmitting means 42 for transmitting the information with the outside of the sealing ring 30.

Abstract: A rubber composition includes (a) a cross linkable fluoro elastomer, (b) a reactive fluorine-containing compound (excluding the cross linkable fluoro elastomer (a)) having a divalent perfluoropolyether structure or divalent perfluoroalkylene structure and containing, in the terminal or a side chain thereof, two or more of alkenyl groups capable of conducting an addition reaction at least with a hydroxyl group in the following organosilicon compound (c), and (c) a reactive organosilicon compound having two or more of hydroxyl groups in the molecule thereof and being capable of conducting an addition reaction with an alkenyl group in the above compound (b), in such amounts wherein the total amount of (b) and (c) is 1 to 10 parts by weight relative to 100 parts by weight of said rubber (a), and further includes a vulcanizing agent and optionally a crosslinking agent; and a sealing agent for a plasma treatment device, which is produced by subjecting said composition to a primary vulcanization and forming, and the

Abstract: A diffusion membrane contains uncalcined polytetrafluoroethylene (PTFE), calcined PTFE and a conductive substance. An electrode has the diffusion layer (membrane) and a catalyst layer disposed thereon. A process for producing diffusion membranes comprises dispersing uncalcined PTFE, calcined PTFE and a conductive substance in a dispersion medium, removing the dispersion medium, adding a liquid lubricant followed by kneading, compressing the resultant kneaded product (preferably a rod-shaped preform) to expand the same into a membrane, and removing the liquid lubricant. The diffusion membrane preferably contains 1 to 30 wt % of the uncalcined PTFE and 5 to 30 wt % of the calcined PTFE. The conductive substance is desirably a combination of graphite and carbon black. The diffusion membrane is free from local variation in properties, has suitable mass producibility and can be produced inexpensively.

Abstract: When the composite sealing material 10 is press-fitted, the swelled portion 28 of the first sealing portion 30 of a first sealing member 20 is press-fitted to impart sealing ability, the second extended portion 36 of a second sealing member 24 is pressed to the opening portion 16 side of a sealing groove 12 through the first extended portion 38 of the first sealing member 20, and the upper surface 34a of the second sealing portion 34 is press-fitted to impart sealing ability.

Abstract: There is disclosed a sealing material for an ant groove, wherein the sealing material is easy to fit to the ant groove and little involves a phenomenon such that the sealing material unfavorably slips out of the ant groove in the form of remaining fixing to the opposite member when the sealed place is opened, and wherein the sealing material can exercise the good sealing function. The sectional shape of the sealing material has: a straight bottom edge 34 which is disposed on a bottom face of the ant groove 12; an arched convex edge 31 which contacts with the other member 20; a first projecting edge 33 which projects outside; a concave inlet portion 39; a second projecting edge which is composed of straight lines 35, 36 that project outside; a straight sloping edge 38; and at least one corner portion 37a-c which is constituted in the range of from the straight bottom edge 34 via the second projecting edge 35, 36 to the sloping edge 38.

Abstract: A gland packing characterized in that a water swelling mineral is stuck or impregnated into a surface or an inner part of a gland packing base material. The water swelling mineral is preferably water swelling mica. This gland packing substantially eliminates seizing and can exhibit an excellent sealing property even if the amount of leakage of an internal fluid or injected fluid for lubrication on a sliding surface is lessened as compared with a conventional example.

Abstract: A reinforcing material-having functional sheet of a sheet-like functional material including a functional powder and a binder resin and, laminated thereon, a reinforcing sheet comprising a woven fabric or a non-woven fabric, which are bonded, wherein the basis weight of the reinforcing sheet, the fiber diameter of the fiber constituting the reinforcing sheet and the functional sheet thickness are in specific ranges. A sheet-like electrode for electric double layer capacitors, which electrode comprises a sheet-like electrode of carbon fine powder and a fluorine-containing polymer resin and, laminated thereon, the reinforcing sheet, and an electric double layer capacitor having this electrode. The functional sheet has strength and no elimination of the functional material powder, and also efficiently exhibits high functional properties.

Abstract: A sealing part that is inexpensive and enable excellent durability to be secured without the need for a predetermined sealing space as would be required for a double sealing structure. A sealing part seals an inside of a reduced pressure vessel from an outside, in which a high-elasticity polymeric material-eroding eroding substance is present and which is comprised of a substrate processing apparatus carrying out predetermined processing on a substrate housed in the reduced pressure vessel. The sealing part has a radical sealing member and a vacuum sealing member. The radical sealing member is disposed on an inside side of the reduced pressure vessel and is resistant to the eroding substance. The vacuum sealing member is made of the high-elasticity polymeric material and is disposed on an outside side of the reduced pressure vessel. At least one refuge space is formed through at least part of the radical sealing member and at least part of the vacuum sealing member being separated from one another.