packaging container with overpressure relief, packing method and system

Abstract

The invention relates to packaging container, packaging method and system. The packaging container, comprises a flexible plastic wall ( 2 ) comprising one or more vents ( 5 ), the one or more vents ( 5 ) adapted to conduct gas ( 29 ) from an inside of the container into an air-channel ( 6 ) and from the air-channel ( 6 ) to an outside ( 7 ) of the container, having air-channel-walls defining the air-channel ( 6 ), comprising internal venting means ( 10 ) for conducting gas ( 29 ) from inside the container into the air-channel ( 6 ), at least partly defined by means of at least one sealed or glued seam ( 9 ) having in at least a partial region a reduced degree of bonding sufficient to allow gas ( 29 ) to escape in response to a suitable pressure. In one or more of the vents ( 5 ), if the vent ( 5 ) is formed to comprise a region of the flexible plastic wall ( 2 ) having an interior wall ( 11 ) and an exterior wall ( 12 ) then the vent ( 5 ) is free of openings penetrating through an interior wall ( 11 ) for conducting gas ( 29 ) from inside the container into a region between interior ( 11 ) and exterior walls ( 12 ), and otherwise either the air-channel-walls of the vent ( 5 ) are free of openings constituting internal venting means ( 10 ) or at least one air-channel-wall of the vent ( 5 ) comprises one or more openings constituting internal venting means ( 10 ).

1 . A packaging container, comprising a flexible plastic wall ( 2 ) which comprises one or more vents ( 5 ), the one or more vents ( 5 )
 adapted to conduct gas ( 29 ) from an inside of the container into an air-channel ( 6 ) and from the air-channel ( 6 ) to an outside ( 7 ) of the container,   having air-channel-walls defining the air-channel ( 6 ),   formed to comprise a region of the flexible plastic wall ( 2 ) having an interior wall ( 11 ) and an exterior wall ( 12 ) constituting air-channel-walls defining the air-channel ( 6 ) therebetween,   comprising internal venting means ( 10 ) for conducting gas ( 29 ) from inside the container into the air-channel ( 6 ),   at least partly defined by means of at least one sealed or glued seam ( 9 ) having in at least a partial region a reduced degree of bonding sufficient to allow gas ( 29 ) to escape in response to a suitable pressure,   
       wherein 
       in one or more of the vents ( 5 ),
 the vent ( 5 ) is free of openings
 penetrating through an interior wall ( 11 ) 
 for conducting gas ( 29 ) from an inner filling-space of the container into a region between interior ( 11 ) and exterior walls ( 12 ). 
 
 
     
     
         2 . The packaging container according to  claim 1 , wherein each of the one or more vents ( 5 ) are improved. 
     
     
         3 . The packaging container according to  claim 1 , wherein the internal venting means ( 10 ) comprise one or more openings in a seam ( 9 ) defining a vent ( 5 ). 
     
     
         4 . The packaging container according to  claim 3 , wherein the internal venting means ( 10 ) comprise at least one opening selected from a perforation in a folded seam ( 9 ), an interruption of a welding in a welded seam ( 9 ) and an interruption of a gluing in a glued seam ( 9 ). 
     
     
         5 . The packaging container according to  claim 1 , further comprising a fibrous filter ( 13 ) in at least a part or parts of an air-channel ( 6 ). 
     
     
         6 . The packaging container according to  claim 5 , wherein at least a part or parts of the fibrous filter ( 13 ) is contained in a sealed or glued seam ( 9 ) having in at least a partial region the reduced degree of bonding. 
     
     
         7 . The packaging container according to  claim 6 , wherein the at least one sealed or glued seam ( 9 ), of the reduced degree of bonding, is a welded seam ( 9 ) comprising the fibrous filter ( 13 ) and flexible walls ( 2 ) fixed to each other at least partly, and a material of at least one of the flexible walls ( 2 ) fixed in the welded seam ( 9 ) is incompatible for welding, with a material of the fibrous filter ( 13 ) fixed in the welded seam ( 9 ), to an extent sufficient to provide a reduced degree of bonding. 
     
     
         8 . The packaging container according to  claim 1 , further comprising an air-channel-wall having at least partly a thickness of at least 70 microns. 
     
     
         9 . The packaging container according to  claim 3 , further comprising spacer means provided in at least one of the one or more openings in a seam ( 9 ) defining a vent ( 5 ). 
     
     
         10 . The packaging container according to  claim 9 , wherein the spacer means comprise one or both of a nonwoven and at least one projection ( 21 ) of a projection height ( 22 ) of at least 50 microns. 
     
     
         11 . A packing method comprising:
 a granular product is provided, and   a package is produced, the package comprising a packaging bag and the package further comprising a quantity of the granular product mixed with a gas, packed into the packaging bag,
 the packaging bag comprising a flexible plastic wall which comprises a vent for venting the bag in a suitable venting orientation of the bag by conducting gas from an inside of the bag into an air-channel and from the air-channel to an outside of the bag,
 the vent having air-channel-walls defining the air-channel, and 
 the vent formed to comprise a region of the flexible plastic wall having an interior wall and an exterior wall constituting air-channel-walls defining the air-channel therebetween, and 
 the vent having internal venting means for conducting gas from inside the container into the air-channel and 
 the vent being at least partly defined by means of one or more sealed or glued seams having in at least a partial region a reduced degree of bonding sufficient to allow gas to escape in response to a suitable pressure, and 
 
   the package is reshaped by at least partially rearranging its contents, for providing the bag in venting orientation and for providing an overpressure in the package at least partly adjacently to internal venting means,   
       wherein
 the packaging bag is used in which the vent is free of openings penetrating through an interior wall for conducting gas from an inner filling-space of the bag into a region between interior and exterior walls, and 
 the packaging bag is used in which at least one of the one or more sealed or glued seams is adapted to open after a pressure-keeping time of at least 1 second, in order to allow gas to escape from the reshaped package only in response to an external squeezing of the package. 
 
     
     
         12 . The method according to  claim 11 , wherein the at least one seam is opened by means of an external squeezing of the package after a pressure-keeping time of at least 1 second in order to allow gas to escape from the reshaped package. 
     
     
         13 . The method according to  claim 12 , wherein the pressure-keeping time is a period of time of at least 1.5 seconds. 
     
     
         14 . The method according to  claim 11 , wherein in the produced package, prior to its reshaping, in at least a portion of an inner filling-space of the packaging bag at least temporarily a pressure, lower than or essentially equivalent to an ambient atmospheric pressure, is provided. 
     
     
         15 . The method according to  claim 11 , wherein at least 1 mass percent of the provided granular product has a granule size below 150 microns. 
     
     
         16 . The method according to  claim 11 , wherein the provided granular product is suitable to be mixed with air and thereby to be rendered into, and to remain, at rest, at least for 30 seconds, in an aerated state in which its apparent density is at most 98% of an apparent density belonging to the granular product in a fully compacted state thereof. 
     
     
         17 . The method according to  claim 11 , wherein the provided granular product contains any one or more of cement, calcium oxide, calcium carbonate, calcium hydroxide, sand, mineral, stone, ore, metal and glass. 
     
     
         18 . The method according to  claim 17 , wherein the provided granular product contains any one or more of cement, calcium oxide, calcium carbonate and calcium hydroxide. 
     
     
         19 . The method according to  claim 18 , wherein at least 1 mass percent of the granular product is cement. 
     
     
         20 . The method according to  claim 12 , wherein the package is externally squeezed by pressing and abutting at least a part or parts, of a top bag wall panel at least partly comprising the vent, to a top surface of the granular product contents. 
     
     
         21 . The method according to  claim 12 , wherein the pressure-keeping time is a period of time of at least 2 seconds. 
     
     
         22 . The method according to  claim 12 , wherein during the pressure-keeping time the at least one sealed or glued seam is prevented from allowing gas to essentially escape from the package. 
     
     
         23 . The method according to  claim 22 , wherein during the pressure-keeping time the at least one sealed or glued seam is prevented from allowing gas to escape from the package. 
     
     
         24 . The method according to  claim 23 , wherein during the pressure-keeping time gas is prevented from escaping from the package. 
     
     
         25 . The method according to  claim 20 , wherein the external squeezing also includes compressing of opposed package sides. 
     
     
         26 . The method according to  claim 11 , wherein the packaging bag is a packaging container according to  claim 1 . 
     
     
         27 . A system comprising a packaging bag ( 1 ) containing a quantity of a granular product ( 27 ) mixed with a gas ( 29 ), the packaging bag ( 1 ) comprising a flexible plastic wall ( 2 ) which comprises a vent ( 5 ), the vent ( 5 )
 adapted to conduct the gas ( 29 ) from an inside of the packaging bag ( 1 ) into an air-channel ( 6 ) and from the air-channel ( 6 ) to an outside ( 7 ) of the packaging bag ( 1 ),   having air-channel-walls defining the air-channel ( 6 ), and   formed to comprise a region of the flexible plastic wall having an interior wall and an exterior wall constituting air-channel-walls defining the air-channel therebetween, and   at least partly defined by a sealed or glued seam ( 9 ) having in at least a partial region a reduced degree of bonding sufficient to allow gas ( 29 ) to escape only in response to an overpressure in the packaging bag ( 1 ) exceeding a predetermined limit,   
       wherein 
       the vent is free of openings penetrating through an interior wall for conducting gas from an inner filling-space of the bag into a region between interior and exterior walls, and the predetermined limit is selected from an interval between 0.0001 bars and 10 bars. 
     
     
         28 . The system according to  claim 27 , wherein the predetermined limit is selected from an interval between 0.001 bars and 10 bars. 
     
     
         29 . The system according to  claim 27 , wherein the predetermined limit is selected from an interval between 0.01 bars and 10 bars. 
     
     
         30 . The system according to  claim 27 , wherein the predetermined limit is selected from an interval between 0.1 bars and 10 bars. 
     
     
         31 . The system according to  claim 27 , wherein the upper limit of the interval is 1 bar. 
     
     
         32 . The system according to  claim 27 , wherein at least 1 mass percent of the granular product ( 27 ) has a granule size below 150 microns. 
     
     
         33 . The system according to  claim 27 , wherein at least some of the granular product ( 27 ), mixed with the gas ( 29 ), is in an aerated state in which an apparent density of the granular product ( 27 ) is at most 98% of an apparent density belonging to the granular product ( 27 ) in a fully compacted state thereof. 
     
     
         34 . The system according to  claim 27 , wherein the granular product ( 27 ) contains any one or more of cement, calcium oxide, calcium carbonate, calcium hydroxide, sand, mineral, stone, ore, metal and glass. 
     
     
         35 . The system according to  claim 34 , wherein the granular product ( 27 ) contains any one or more of cement, calcium oxide, calcium carbonate and calcium hydroxide. 
     
     
         36 . The system according to  claim 35 , wherein at least 1 mass percent of the granular product ( 27 ) is cement. 
     
     
         37 . The system according to  claim 27 , wherein a filling mouth of the packaging bag is closed. 
     
     
         38 . The system according to  claim 27 , wherein the packaging bag ( 1 ) is a packaging container according to  claim 1 .