Package bag and method for producing same

Abstract

A manufacturing method of a package bag ( 10 ) according to the present invention includes: a cured portion forming step of forming a cured portion ( 15 a, 15 b ) on at least one side of a forming position of a rib ( 14 ) by crystallizing at least a portion of a resin constituting a film ( 11 ) by heating and cooling the film ( 11 ); and a rib forming step of forming a rib ( 14 ) by pressing the film ( 11 ) using concave and convex molds. According to the present invention, it is possible to maintain an opening state of a spout ( 12 ). Further, since additional material is not required, it is possible to suppress increase in the thickness of the package bag ( 10 ) and to reduce the bulkiness of the package bags.

1 . A manufacturing method of a package bag including: a spout defined by a pair of flow passage forming sealing portions which are formed by sealing two films at both side portions of a flow passage; a groove rib formed so as to protrude outward of the film and extend along the flow passage; and a cured portion formed on at least one side of the rib by crystallizing at least a portion of a resin constituting the film, the manufacturing method comprising:
 a cured portion forming step of forming the cured portion on at least one side of a forming position of the rib by crystallizing at least a portion of the resin constituting the film by heating and cooling the film; and   a rib forming step of forming the rib by pressing the film using concave and convex molds.   
     
     
         2 . The manufacturing method of a package bag according to  claim 1 , wherein the rib has a width of 0.5 to 3 mm and a height of 0.5 to 3 mm. 
     
     
         3 . The manufacturing method of a package bag according to  claim 1 , wherein in the rib forming step, the rib is formed without heating. 
     
     
         4 . The manufacturing method of a package bag according to  claim 1 , wherein
 in the cured portion forming step, the film is cooled by molds, whose shape corresponds to the shape of the cured portion, abutting both surfaces of the film, and a roughening processing is performed on an outer surface of the cured portion of the film by using a mold having an abutting surface which abuts an outer surface of the film and on which a sandblast processing is performed.   
     
     
         5 . The manufacturing method of a package bag according to  claim 1 , further comprising a step of providing an opening assisting line which intersects the rib. 
     
     
         6 . A package bag comprising:
 a spout which is defined by a pair of flow passage forming sealing portions which are formed by sealing two films at both side portions of a flow passage;   a groove rib which is formed so as to protrude outward of the film and extend along the flow passage; and   a cured portion which is formed on at least one side of the rib by crystallizing at least a portion of a resin constituting the film.   
     
     
         7 . The package bag according to  claim 6 , wherein the rib has a width of 0.5 to 3 mm and a height of 0.5 to 3 mm. 
     
     
         8 . The package bag according to  claim 6 , further comprising an opening assisting line which is provided so as to intersect the rib. 
     
     
         9 . The package bag according to  claim 6 , wherein an outer surface of the cured portion of the film is roughened. 
     
     
         10 . The package bag according to  claim 6 , wherein:
 the film is formed in a substantially rectangular shape;   among the pair of flow passage forming sealing portions, one flow passage forming sealing portion is provided on a first side of the film, and the other flow passage forming sealing portion is provided on a second side of the film adjacent to the first side; and   at least one of the ribs is disposed on an intersection point between a line passing through a position of the flow passage forming sealing portion on the first side which is the closest to a third side opposite to the first side and extending substantially parallel to the third side, and a line passing through a position of the flow passage forming sealing portion on the second side which is the closest to a fourth side opposite to the second side and extending substantially perpendicular to the third side.   
     
     
         11 . The manufacturing method of a package bag according to  claim 2 , wherein in the rib forming step, the rib is formed without heating. 
     
     
         12 . The manufacturing method of a package bag according to  claim 2 , wherein
 in the cured portion forming step, the film is cooled by molds, whose shape corresponds to the shape of the cured portion, abutting both surfaces of the film, and a roughening processing is performed on an outer surface of the cured portion of the film by using a mold having an abutting surface which abuts an outer surface of the film and on which a sandblast processing is performed.   
     
     
         13 . The manufacturing method of a package bag according to  claim 3 , wherein
 in the cured portion forming step, the film is cooled by molds, whose shape corresponds to the shape of the cured portion, abutting both surfaces of the film, and a roughening processing is performed on an outer surface of the cured portion of the film by using a mold having an abutting surface which abuts an outer surface of the film and on which a sandblast processing is performed.   
     
     
         14 . The manufacturing method of a package bag according to  claim 2 , further comprising a step of providing an opening assisting line which intersects the rib. 
     
     
         15 . The manufacturing method of a package bag according to  claim 3 , further comprising a step of providing an opening assisting line which intersects the rib. 
     
     
         16 . The manufacturing method of a package bag according to  claim 4 , further comprising a step of providing an opening assisting line which intersects the rib. 
     
     
         17 . The package bag according to  claim 7 , further comprising an opening assisting line which is provided so as to intersect the rib. 
     
     
         18 . The package bag according to  claim 7 , wherein an outer surface of the cured portion of the film is roughened. 
     
     
         19 . The package bag according to  claim 8 , wherein an outer surface of the cured portion of the film is roughened. 
     
     
         20 . The package bag according to  claim 7 , wherein:
 the film is formed in a substantially rectangular shape;   among the pair of flow passage forming sealing portions, one flow passage forming sealing portion is provided on a first side of the film, and the other flow passage forming sealing portion is provided on a second side of the film adjacent to the first side; and   at least one of the ribs is disposed on an intersection point between a line passing through a position of the flow passage forming sealing portion on the first side which is the closest to a third side opposite to the first side and extending substantially parallel to the third side, and a line passing through a position of the flow passage forming sealing portion on the second side which is the closest to a fourth side opposite to the second side and extending substantially perpendicular to the third side.