Abstract: A filter bag (1) comprises a first thin plastic film (22); a second thin plastic film (21) having substantially the same size with the first plastic film and sealed to the first plastic film at a first side-peripheral edge (2a), a second side-peripheral edge (2b) opposite to the first side-peripheral edge and a bottom peripheral edge (2d) thereof to provide an open-top interior, and a filter sheet (5) having a length substantially equal to the first and second plastic films and a width smaller than the first and second plastic films. The filter sheet has a first longitudinal edge (5a) interposed and sealed together between the first side-peripheral edges of the first and second plastic films and a second longitudinal edge (5b), opposite to the first longitudinal edge, sealed to the inside of the first plastic film at an intermediate position in width of the filter bag.

Abstract: Disclosed is a membrane filter system comprising an integral plastic holder (1, 23) having a filter receiving section (2, 24) for receiving a membrane filter (3, 30) that collects target microorganism contained in sample solution, a funnel mount (9, 25) positioned at a level higher than the filter receiving section for carrying thereon a cup-shaped paper funnel (12, 33) adapted to receive the sample solution, and a drainage (7, 28) communicated with the filter receiving section. The funnel has a bottom sheet or a paper filter (14, 35) and a bottom peripheral flange (15, 36) surrounding the bottom sheet. Resin seal means (11, 22) is fitted to the funnel mount to provide liquid-tight engagement between the funnel and the holder. The bottom sheet of the funnel is positioned above the membrane filter and serves as a primary filter for collecting particles in the sample solution larger than the target microorganism before the sample solution reaches the membrane filter.

Abstract: A filter bag (1) comprises a first thin plastic film (22); a second thin plastic film (21) having substantially the same size with the first plastic film and sealed to the first plastic film at a first side-peripheral edge (2a), a second side-peripheral edge (2b) opposite to the first side-peripheral edge and a bottom peripheral edge (2d) thereof to provide an open-top interior, and a filter sheet (5) having a length substantially equal to the first and second plastic films and a width smaller than the first and second plastic films. The filter sheet has a first longitudinal edge (5a) interposed and sealed together between the first side-peripheral edges of the first and second plastic films and a second longitudinal edge (5b), opposite to the first longitudinal edge, sealed to the inside of the first plastic film at an intermediate position in width of the filter bag.

Abstract: Disclosed is a membrane filter system comprising an integral plastic holder (1, 23) having a filter receiving section (2, 24) for receiving a membrane filter (3, 30) that collects target microorganism contained in sample solution, a funnel mount (9, 25) positioned at a level higher than the filter receiving section for carrying thereon a cup-shaped paper funnel (12, 33) adapted to receive the sample solution, and a drainage (7, 28) communicated with the filter receiving section. The funnel has a bottom sheet or a paper filter (14, 35) and a bottom peripheral flange (15, 36) surrounding the bottom sheet. Resin seal means (11, 22) is fitted to the funnel mount to provide liquid-tight engagement between the funnel and the holder. The bottom sheet of the funnel is positioned above the membrane filter and serves as a primary filter for collecting particles in the sample solution larger than the target microorganism before the sample solution reaches the membrane filter.