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: 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.