Abstract: The present invention provides a filter element made wholly of fluorocarbon resin and production thereof. As the filter element is wholly made of fluorocarbon resin, it has an excellent chemicals resistance, and temperature resistance and is free from metal leaching. Though it has been difficult to produce such a fluorocarbon filter element free from leakage, in the present invention it can be produced at high yield.

Abstract: The present invention relates to a filter element suitable for the purification of gas, in which spaces are constituted with porous spacer between plural membrane filters. Particles or dusts captured in the filter element of the present invention are prevented from rescattering under the impulsive pressure at the initiation or termination of the filtration, so that the high precision of the filtration can be achieved.

Abstract: The disclosure relates to a filter in use for centrifugal separator including a filter film between a sample chamber and a filtrate chamber. The filter film is inclined or parallel to an axis of the filter. Accordingly, when the filter is utilized for either the angle rotor type and swing rotor type of centrifugal separators, the filter is positioned, during operation, so as to be inclined or parallel to the direction of the centrifugal force so that the residue contained in the liquid sample in the sample chamber moves radially outwardly with respect to the axis of the rotors so as to slide on the filter film or so as to leave from the filter film. Thus, the filter film will not easily result in clogging with the residue so that the high filtration speed can be maintained for a long period of time.

Abstract: The present invention provides a filter element made wholly of fluorocarbon resin, including as essential elements a filter material produced by folding a sandwich-form sheet comprising a filter membrane made of a fluorocarbon resin and net supporters made of a thermoplastic fluorocarbon resin superimposed on the both surfaces thereof into a pleat form and liquid-tightly welding the edge parts of the both sides of the pleated sheet, sealed end parts produced by embedding the both end parts of said filter material except the central openings into a thermoplastic fluorocarbon resin to force the resin into the pleats, whereby the both end parts are each integrally and tightly welded, and fluorocarbon resin caps welded liquid-tightly with said sealed end parts, and production thereof.

Abstract: The present invention provides a filter element made wholly of fluorocarbons resin, comprising as essential elements a filter material produced by folding a sandwich-form sheet comprising a filter membrane made of a fluorocarbon resin and net supporters made of a thermoplastic fluorocarbon resin superimposed on the both surfaces thereof into a pleat form and liquid-tightly welding the edge parts of the both sides of the pleated sheet, sealed end parts produced by embedding the both end parts of said filter material except the central openings into a thermoplastic fluorocarbon resin to force the resin into the pleats, whereby the both end parts are each integrally and tightly welded, and fluorocarbon resin caps welded liquid-tightly with said sealed end parts, and production thereof.