Multi-bag and method of producing the same, and multi-bag for bag-making and filling

Abstract

A multi-bag comprises a multi-film made by superposing at least an inner film and an outer film and sealing the cylindrically curved superposed region to form a back seal. The multi-film constituting the multi-bag is a double film formed by flattening a tube-like film into a two-layer form, with the opposite end edges, which are parallel with the direction of extrusion, continuing to each other. The multi-bag is formed in a sealed state by a back seal, a planar seal at one end, and a planar seal at the other end. The supply system for the multi-film may be such that one system is prepared for each double so as to simplify the device. Further, in the film supply process, it is possible to obtain a multi-bag of high quality without applying a shift-preventive means to between the multi-films.

1 . A multiple bag structured by sealing a portion in which a multiple film formed by overlapping at least an inner film and an outer film is bent in a tubular shape and is overlapped, wherein each of the films of the multiple film structuring said multiple bag is connected with each other in both side end edges thereof.  
   
   
       2 . A multiple bag as claimed in  claim 1 , wherein the multiple film structuring the multiple bag is constituted by a multiple film obtained by forming a tubular film in a flat shape so as to form a two-ply film and connecting both side end edges thereof to each other.  
   
   
       3 . A multiple bag as claimed in  claim 1 , wherein two opposing films of the tubular film are set as an inner film and an outer film, a back lining seal portion is structured by welding a portion near both sides of the connected end edges of said film and the outer film, and a lateral seal portion is structured by welding a portion near both sides of the end edge in which said inner film and the outer film are not connected.  
   
   
       4 . A multiple bag as claimed in  claim 1 , wherein the end edges of the tubular bent multiple film are overlapped with each other in a flat shape, and the overlapped portion is back sealed.  
   
   
       5 . A multiple bag as claimed in  claim 1 , wherein a plug body mounting hole is formed in a step of bending the multiple film in the tubular shape, and a plug body is provided in the plug body mounting hole in accordance with a welding process.  
   
   
       6 . A multiple bag as claimed in  claim 1 , wherein the portion formed by bending the multiple film in the tubular shape and overlapping the multiple film is formed in one side end edge of the multiple bag, and a plug body is held in an inner side of the overlapped portion.  
   
   
       7 . A multiple bag structured by overlapping a multiple film formed by overlapping at least an inner film and an outer film in a two-fold shape and sealing both end portions, wherein the multiple film structuring said multiple bag is overlapped in a two-fold shape such that both side end edges in which the respective films are connected to each other are in the same side, and both end edge sides in which the respective films of the multiple film are connected to each other form an open side of the bag.  
   
   
       8 . A multiple bag as claimed in  claim 7 , wherein the multiple film is constituted by a multiple film obtained by forming a tubular film in a flat shape so as to form a two-ply film and connecting both side end edges thereof to each other.  
   
   
       9 . A method of producing a multiple bag structured by sealing a portion in which a multiple film formed by overlapping at least an inner film and an outer film is bent in a tubular shape and is overlapped, wherein the multiple film is formed in accordance with an inflation method or a T-die extruding method so as to be sequentially overlapped by extruding, and bonding both side end edges parallel to the extruding direction of each of the overlapped films in accordance with a welding means, a bonding means or the like so as to form a multiple film connected to each other, and the multiple bag is structured by sealing the portion in which the multiple film is bent in the tubular shape and overlapped.  
   
   
       10 . A method of producing a multiple bag structured by sealing a portion in which a multiple film formed by overlapping at least an inner film and an outer film is bent in a tubular shape and is overlapped, wherein the multiple film is structured by forming a tubular film in accordance with an inflation method so as to be sequentially extrude, forming the extruded tubular film in a flat shape so as to form a two-ply film, forming a multiple film in which both side end edges parallel to the extruding direction are connected to each other, and sealing the portion in which the multiple film is bent in the tubular shape and overlapped.  
   
   
       11 . A multiple bag for filling and closing a bag-making, in which a tubular is structured in a flat shape such that two opposing films form an inner film and an outer film, a back lining seal portion is structured by welding a portion near both sides of the end edges in which said inner film and the outer film are connected, and a lateral seal portion is structured by welding a portion near both sides of the end edges in which said inner film and the outer film are not connected, wherein said tubular film is constituted by a tubular co-extrusion inflation film having a polyolefin layer in both sides of a core layer.  
   
   
       12 . A multiple bag for filling and closing a bag-making, in which a tubular is structured in a flat shape such that two opposing films form an inner film and an outer film, a back lining seal portion is structured by welding a portion near both sides of the end edges in which said inner film and the outer film are connected, and a lateral seal portion is structured by welding a portion near both sides of the end edges in which said inner film and the outer film are not connected, wherein said tubular film is constituted by a tubular co-extrusion inflation film having a polyolefin layer in both sides of a un-oriented polyamide layer.  
   
   
       13 . A multiple bag as claimed in  claim 2 , wherein two opposing films of the tubular film are set as an inner film and an outer film, a back lining seal portion is structured by welding a portion near both sides of the connected end edges of said film and the outer film, and a lateral seal portion is structured by welding a portion near both sides of the end edge in which said inner film and the outer film are not connected.  
   
   
       14 . A multiple bag as claimed in  claim 2 , wherein the end edges of the tubular bent multiple film are overlapped with each other in a flat shape, and the overlapped portion is back sealed.  
   
   
       15 . A multiple bag as claimed in  claim 2 , wherein a plug body mounting hole is formed in a step of bending the multiple film in the tubular shape, and a plug body is provided in the plug body mounting hole in accordance with a welding process.  
   
   
       16 . A multiple bag as claimed in  claim 3 , wherein a plug body mounting hole is formed in a step of bending the multiple film in the tubular shape, and a plug body is provided in the plug body mounting hole in accordance with a welding process.  
   
   
       17 . A multiple bag as claimed in  claim 4 , wherein a plug body mounting hole is formed in a step of bending the multiple film in the tubular shape, and a plug body is provided in the plug body mounting hole in accordance with a welding process.  
   
   
       18 . A multiple bag as claimed in  claim 13 , wherein a plug body mounting hole is formed in a step of bending the multiple film in the tubular shape, and a plug body is provided in the plug body mounting hole in accordance with a welding process.  
   
   
       19 . A multiple bag as claimed in  claim 14 , wherein a plug body mounting hole is formed in a step of bending the multiple film in the tubular shape, and a plug body is provided in the plug body mounting hole in accordance with a welding process.  
   
   
       20 . A multiple bag as claimed in  claim 2 , wherein the portion formed by bending the multiple film in the tubular shape and overlapping the multiple film is formed in one side end edge of the multiple bag, and a plug body is held in an inner side of the overlapped portion.