Abstract: The object of the present invention is to provide a gasket forming mold with a structure in which curling of the reversing section of the gasket molding does not occur easily. To achieve said object, the forming mold for integrally forming an endless shaped gasket has forming grooves as cavities in the parting surfaces of the forming mold and the forming grooves have a reversing section in a part thereof. The reversing section has two linear portions and the ends of the two linear portions are connected by an arc-shaped curved section. The two linear portions are arranged at literally-symmetrical positions and are arranged so that a distance therebetween is enlarged little by little from one end toward the other. The ends where said distance is enlarged are connected by the circular arc-shaped curved section.

Abstract: The object of the present invention is to provide a gasket forming mold with a structure in which curling of the reversing section of the gasket molding does not occur easily. To achieve said object, the forming mold for integrally forming an endless shaped gasket has forming grooves as cavities in the parting surfaces of the forming mold and the forming grooves have a reversing section in a part thereof. The reversing section has two linear portions and the ends of the two linear portions are connected by an arc-shaped curved section. The two linear portions are arranged at literally-symmetrical positions and are arranged so that a distance therebetween is enlarged little by little from one end toward the other. The ends where said distance is enlarged are connected by the circular arc-shaped curved section.

Abstract: A quaternary copolymer, fluorine-containing elastomer having a copolymerization composition comprising: (A) 2.0 to 8.0 mol % of vinylidene fluoride, (B) 60.0 to 70.0 mol % of tetrafluoroethylene, (C) 35.0 to 25.0 mol % of perfluoro(lower alkyl vinyl ether) or perfluoro(lower alkoxy-lower alkyl vinyl ether), and (D) 0.2 to 3.0 mol % of a perfluoro unsaturated nitrile compound, and having a Mooney viscosity ML1+10(121° C.) of 65 to 110, as well as a vulcanizable fluorine-containing elastomer composition comprising said fluorine-containing elastomer and a bisamidoxime compound in an amount of 0.2 to 5 parts by weight based on 100 parts by weight of the fluorine-containing elastomer. A sealing material obtained by vulcanization-molding of the fluorine-containing elastomer has not only excellent compression set characteristics and plasma resistance, but also low adhesion to metal at a higher temperature, specifically 150° C.

Abstract: In a water-proof structure for an opening of a device case, which includes a packing installed in a peripheral groove around a cover and compressed between the inner periphery of the opening and the groove when the cover is inserted into the opening, the packing is configured to have a flat contact surface in contact with the bottom of the groove and have a cross section having a width larger than the height, and the cross section of the packing also has a flat bottom or an inner side to fit the groove bottom that is also flat in a cross section while the outer side has a convex shape so that the whole cross section has a D-shaped form, in order to prevent degraded sealing capability or improper installation due to twist of the packing in the groove.

Abstract: A sealing structure in which sealing is made by a seal ring installed in a dovetail groove where only an inner surface on one side of the groove is an inclined surface. In the sealing structure, the seal ring is less likely to come out of the dovetail groove, resistance of insertion of the seal ring into the dovetail is small, and particles are less likely to occur in the structure. The seal ring is formed of a rubber-like elastic material and is installed in the dovetail groove where the first inner surface on one side of the groove is inclined falling to the inside of the groove.

Abstract: For easy and correct installation of a rubber-like seal ring into a dovetail groove and for prevention of falling away of the seal ring from the dovetail groove and generation of particles, a seal ring (3) has a convex bottom portion (3a) made to be in contact with a groove bottom (12c), side protruding portion (3b, 3c) formed at both sides thereof and made to be in contact with inner slope surfaces (12d, 12e) of the dovetail groove (12), and a convex head portion (3d) formed to protrude between ends at the side opposite to the bottom section (3a) of both side protruding portions (3b, 3c), and exposed to the outside of the dovetail groove (12), width W3 of the head portion (3d) is smaller than width W1 between groove shoulders (12a, 12b), and width W4 between peaks of the side protruding portions (3b, 3c) is larger than width W1.

Abstract: A sealing structure in which sealing is made by a seal ring (3) installed in a dovetail groove (12) where only an inner surface (12a) on one side of the groove (12) is an inclined surface. In the sealing structure, the seal ring (3) is less likely to come out of the dovetail groove (12), resistance of insertion of the seal ring (3) into the dovetail (12) is small, and particles are less likely to occur in the structure. The seal ring (3) is formed of a rubber-like elastic material and is installed in the dovetail groove (12) where the first inner surface (12a) on one side of the groove is inclined falling to the inside of the groove.

Abstract: A seal molding material for cell electrolytic solution, which comprises an EPDM composition comprising a peroxide-crosslinkable EPDM and an organic peroxide, the seal molding material being for use at the electrode site of a nickel-hydrogen cell, wherein the EPDM composition comprises preferably 100 parts by weight of a peroxide-crosslinkable EPDM, 10 to 150 parts by weight of a filler and 1 to 8 parts by weight of an organic peroxide, and not more than 40 parts by weight of hydrocarbon-based oil can be further contained. The seal material molded from the seal molding material for cell electrolytic solution has a sufficient durability against a potassium hydroxide-based electrolytic solution and a longer life, and is free from any deterioration, when energized at the electrode site of a nickel-hydrogen cell.

Abstract: A seal molding material for cell electrolytic solution, which comprises an EPDM composition comprising a peroxide-crosslinkable EPDM and an organic peroxide, the seal molding material being for use at the electrode site of a nickel-hydrogen cell, wherein the EPDM composition comprises preferably 100 parts by weight of a peroxide-crosslinkable EPDM, 10 to 150 parts by weight of a filler and 1 to 8 parts by weight of an organic peroxide, and not more than 40 parts by weight of hydrocarbon-based oil can be further contained. The seal material molded from the seal molding material for cell electrolytic solution has a sufficient durability against a potassium hydroxide-based electrolytic solution and a longer life, and is free from any deterioration, when energized at the electrode site of a nickel-hydrogen cell.

Abstract: A seal molding material for cell electrolytic solution, which comprises an EPDM composition comprising a peroxide-crosslinkable EPDM and an organic peroxide, the seal molding material being for use at the electrode site of a nickel-hydrogen cell, wherein the EPDM composition comprises preferably 100 parts by weight of a peroxide-crosslinkable EPDM, 10 to 150 parts by weight of a filler and 1 to 8 parts by weight of an organic peroxide, and not more than 40 parts by weight of hydrocarbon-based oil can be further contained. The seal material molded from the seal molding material for cell electrolytic solution has a sufficient durability against a potassium hydroxide-based electrolytic solution and a longer life, and is free from any deterioration, when energized at the electrode site of a nickel-hydrogen cell.