JPH11236060A - Packaging bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a dragged trace and wrinkle from occurring at a belt- shaped fused part of a longitudinal heat sealed part of a packaging bag adjacent to a storage space for an object to be packaged. SOLUTION: Base material film layers on the opposite sides are welded through a thermal bonding resin at a longitudinal heat seal part 3 of the packaging bag 1 at an area adjacent to a storage space 5 of an object to be packaged to form a belt-shaped welded part 6. On the other hand, an irregular seal part 7 is formed from the part 6 to a side edge or to the vicinity thereof, and a recessed or protruding strip 8 is provided on the part 6 so as to be continuous in the length direction of a laminated film layer 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging bag suitable for packaging liquids, viscous substances, powdery and granular materials, and other objects to be packaged. The present invention relates to an improvement in a heat-sealed portion in the vertical direction when packaging.

[0002]

2. Description of the Related Art For example, automatic filling is performed using a laminated film having a base film layer made of paper, stretched plastic film, metal foil, etc., and a heat-sealing resin layer directly or indirectly laminated thereon. In packaging the object under the action of the machine, as shown in FIG. 4, the laminated film 103 unwound from the take-up roll 101 is used.
Are sequentially passed through the respective guide rolls 105 and 107, and then folded in the width direction by a folding device 109, and then the laminated film 10 in a folded state is folded in two.
3 is a vertical seal roll 1 that doubles as a film drawer roll
11 and the horizontal seal roll 113 have been widely and generally used in the past. Here, in the vertical seal roll 111, a pair of rotating rolls 11 are used.
1a, a flange-shaped heat sealing blade 1 provided on each of
11b, the free end portion of the laminated film 103 is sandwiched therebetween, and a vertical heat seal is applied to the free end portion as shown by diagonal lines in the figure. A heat seal blade 113b formed to extend in the length direction and spaced at a predetermined interval in the circumferential direction of the roll 113a also has a predetermined length in the length direction of the laminated film 103 as shown by hatching in the drawing. The heat seal in the horizontal direction is to be performed at intervals.

[0003] Here, for example, the packaging of the liquid in the laminated film 103 which is subjected to the heat sealing in the vertical direction and the horizontal direction to form a packaging bag is carried out by the nozzle 115 as a filling means. This is performed by supplying a liquid to the inside of the laminated film 103 after the sealing is completed, and the packaging bag after the completion of the liquid packaging is horizontally sealed by the cutter roll 117 disposed below the horizontal sealing roll 113. From the middle of the department,
For example, they are cut one by one.

In manufacturing a packaging bag with such an automatic filling machine, a vertical seal roll 111 which also functions as a drawing roll for the laminated film 103 is used.
Above all, it is necessary that the free end portion of the folded laminated film 103 be strongly clamped by the flange-shaped heat seal blade 111b so that no slip occurs between the film 103 and the vertical seal roll 111. In each of the pair of heat seal blades 111b, an uneven portion such as a knurled portion is provided, and the uneven portions are engaged with each other via the free end portion of the laminated film 103, so that the It is intended to prevent the occurrence of slip between the two.

[0005] Therefore, the vertical heat-sealed portion of the packaging bag manufactured in this manner is sandwiched between the uneven portions of the heat-sealing blade 111b as shown in FIG. 3. Concavo-convex seal part 1 contributing to drawer 3
19 and the inside of the packaging bag from the concave-convex sealing portion 119 to partition the packaged accommodation space 121 and mainly contribute to the development of the bag breaking strength under the intervention of the heat-sealing resin. It has a band-like fusion part 123.

[0006]

Incidentally, a pair of flange-shaped heat seal blades 111b used for forming such a vertical heat seal portion can engage with each other as shown in an enlarged sectional view in FIG. , And a flat portion 111d positioned adjacent to the uneven portion 111c. Here, the diameter D of the flat portion 111d is equal to the convex portion diameter D of the uneven portion 111c. ₀
Since both heat seal blades 111b are inevitably smaller, the two heat seal blades 111b are rotated in synchronization with each other, and the laminated film 103 sandwiched between the two heat seal blades is rotated at a speed corresponding to the peripheral speed of the tip of the convex portion. When pulled out, the peripheral speed of the flat portion 111d contributing to the formation of the band-shaped fused portion 123 becomes
The speed is lower than the film withdrawal speed, and as a result, the flat portions 111
Drag marks are generated on the peripheral surface of d, and severely, wrinkles due to the drag occur, and the appearance of the packaging bag is greatly impaired, and the generated wrinkles cannot provide a complete sealing state. There is a problem that the liquid as the packaged material leaks out through the wrinkled band-shaped fused portion 123.

[0007] By the way, the occurrence of drag traces on the band-like fused portion 123 is particularly serious when aluminum or other metal foil, paper, or the like is used as the base film layer. This was particularly significant in a thin laminated film using a film or the like as a base film.

[0008] The present invention has been made as a result of studying to solve such problems in the prior art, and the purpose of the invention is to provide dragging traces and wrinkles on a band-like fused portion. It is an object of the present invention to provide a packaging bag which can sufficiently prevent the occurrence of the above-mentioned problems.

[0009]

SUMMARY OF THE INVENTION A packaging bag according to the present invention comprises a laminated film comprising a base film layer and a heat-sealing resin layer laminated directly or indirectly on the base film layer. Each of the heat seals is applied to divide the accommodation space of the packaged object, and in the heat seal portion in the vertical direction, an area adjacent to the packaged object accommodation space is
While the base film layers on both the front and back are formed into a band-shaped fused portion to be fused with the intervention of the heat-fusible resin, the portion from the band-shaped fused portion to the periphery of the packaging bag or a portion in the vicinity thereof is formed as an uneven seal portion. In the above, the strip-shaped fused portion is provided with a plurality of uneven stripes continuous in the length direction of the laminated film.

[0010] In this packaging bag, the uneven sealing portion of the vertical heat seal portion is formed in substantially the same manner as described in the prior art. Flat part 1 of heat seal blade 111b
11d can be formed by providing an annular groove and a projection that fit together, and according to this, the diameter of the annular projection of each heat seal blade is smaller than that of the flat portion 111d. Naturally larger than the diameter,
Therefore, since the peripheral speed of the annular projection is also increased, even if the laminated film is pulled out with the above-mentioned uneven portion of the heat sealing blade, the band-shaped fused portion, and further, the heat sealing of the uneven strip is performed. The amount of slip with respect to the blade can be effectively reduced as compared with the conventional technology,
It is possible to effectively remove the risk of dragging traces, wrinkles, and the like on the belt-shaped fused portion.

[0011]

Embodiments of the present invention will be described below. FIG. 1 is a plan view showing an embodiment of the present invention, in which a packaging bag 1 has a vertical sealing portion 3 in which a free end portion of a laminated film 2 folded in the width direction is heat-sealed in a vertical direction. And two horizontal seal portions 4 which are heat-sealed in the lateral direction at two locations spaced apart in the longitudinal direction of the laminated film 2 to define the accommodation space 5 for the article to be packaged. . The imaginary line located in the middle part in the width direction of the horizontal seal portion 4 in the figure indicates the line to be cut and separated for each of the strip-shaped packaging bags manufactured by the automatic filling machine.

Here, in the vertical sealing portion 3 of the packaging bag 1, a region adjacent to the storage space 5 is formed into a band-like fusion film in which the base film layers on both the front and back sides are fused with the intervention of a heat fusion resin. And the packaging bag 1
And the vicinity thereof, and the region up to the vicinity in the figure, are used as the uneven sealing portion 7 in which bending strain remains in the base film layer, and the band-like fused portion 6 is provided with the laminated film 2.
Are provided in the longitudinal direction.

FIG. 2 is an enlarged sectional view showing the manner in which such a vertical seal portion 3 is formed. In the figure, reference numeral 11 denotes a pair of flange-like heat seals provided on a vertical seal roll in the same manner as described in the prior art. Show the blade. These heat seal blades 11 here form the uneven seal portion 7 of the vertical seal portion 3, for example, have the respective uneven portions 12 in a substantially pyramid shape and meshing with each other, and the band-shaped fused portion 6, The concave-convex ridge portion 1 composed of annular grooves and protrusions that fit with each other and functions to form the concave-convex ridges 8.
3

The concave and convex strip 13 shown in the drawing has a cross-sectional shape in which one heat sealing blade 11 has arc-shaped grooves 13a arranged adjacent to each other in the axial direction, and the other heat sealing blade 11 has a cross-sectional shape. 11 has a cross-sectional shape in which triangular ridge-shaped protrusions 13b fitted into the grooves 13a are arranged adjacent to each other in the axial direction. In the case where the concavo-convex stripe portion 13 is configured in this manner, a relatively large space is secured on both sides of the bottom portion and the top portion of each of the one arc-shaped groove portion 13a and the other triangular mountain-shaped protrusion 13b. This makes it possible to hold a large amount of the heat-sealing resin melted by the heat-sealing blade 11 in the space, so that the heat-sealing strength in the band-shaped fusion-bonded portion 6 of the packaging bag 1 is sufficiently increased. In addition, due to the pressing force of the laminated film by the two heat sealing blades 11, the heat-sealing resin is
It is possible to effectively prevent a large amount of the packaged product from being pushed out to the storage space 5 side.

[0015] In this case, more preferably, the concave and convex ridge portion 13 having the arc-shaped groove portion 13a;
Concave and convex stripes 13 having triangular mountain-shaped protrusions 13b
Each of the peak diameter and the valley diameter of
The peripheral speed at the time of rotation of the heat sealing blade 11 is also substantially equalized by making them equal to those in the uneven portion 12. By the way, the cross-sectional shapes of the grooves and the protrusions of the concave and convex strips 13 can be appropriately changed as required, and for example, each of the shapes as shown in FIG.

Further, the heat seal blade 11 shown in FIG.
In the portion where the band-shaped fusion bonding portion 6 is formed, a small flat portion 15 for forming a flat seal portion 14 located adjacent to the packaged object accommodation space 5 is also provided, but preferably such a portion is provided. By setting the pressing force of the smoothing portion 15 on the laminated film 2 to be sufficiently small, drag marks, which may occur on the surface of the flat seal portion 14 as described in the related art, can be formed.
It can be reduced to a negligible extent. Here, in order to more effectively remove the occurrence of drag traces, the illustrated smooth portion 15 can also be formed as an uneven stripe portion.

When the vertical seal portion 3 is formed on the laminated film 2 by the heat seal blade 11 configured as described above, the concave-convex seal portion 7 is formed by the concave-convex portion 12 contributing to the drawing of the laminated film 2. And the uneven strip part 1
3, the concavo-convex stripes 8 in the band-like fused portion 6 are formed, and in forming the vertical seal portion 3, the peripheral speed of each crest of the concavo-convex stripes 13 is
Since the peripheral speed of the crests of the concave and convex portions 12 and, consequently, the speed of pulling out the laminated film 2 or the speed close thereto, the film withdrawal speed of the feeding speed of the laminated film portion sandwiched by the concave and convex strips 13 By effectively removing the delay with respect to the speed, the occurrence of drag traces, wrinkles, etc. on the band-like fused portion 6, especially the uneven strip 8, is sufficiently prevented regardless of the constituent material and thickness of the laminated film 2. be able to.

[0018]

As is apparent from the above description, according to the present invention, particularly, in the heat-sealed portion of the laminated film in the longitudinal direction, it is continuously formed in the band-like fused portion in the longitudinal direction of the laminated film. By providing the irregularities extending to extend, the moving speed of the portion of the laminated film where the irregularities are formed can be advantageously brought close to that of the irregular seal portion,
For this reason, it is possible to sufficiently prevent the occurrence of drag traces, wrinkles, and the like on the strip-like fused portion due to the drag of the above-mentioned uneven strip, and eventually the strip-shaped fused portion against the heat sealing blade.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a formation state of a vertical seal portion together with a heat seal blade.

FIG. 3 is a cross-sectional view showing another aspect of the uneven stripe portion.

FIG. 4 is a main part side view showing a bag making process by an automatic filling machine.

FIG. 5 is a plan view showing a packaging bag made according to the position shown in FIG. 4;

FIG. 6 is an enlarged cross-sectional view showing a form of forming a vertical sealing portion of a conventional packaging bag together with a heat sealing blade.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Packaging bag 2 Laminated film 3 Vertical seal part 4 Horizontal seal part 5 Storage space 6 Band fusion part 7 Irregular seal part 8 Irregular stripe 11 Heat seal blade 12 Irregular part 13 Irregular stripe 13a Groove part 13b Projection 14 Flat seal part 15 Smoothing part

Claims (1)

[Claims] 1. A packaging bag comprising a laminated film having a base film layer and a heat-sealing resin layer, each of which is subjected to heat sealing in a vertical direction and a horizontal direction to define a space for accommodating an object to be packaged. In the vertical heat-sealing part, the area adjacent to the space for accommodating the object to be packaged is used as a band-like fusion part where the base material film layers on both the front and back are fused with the intervention of the heat-fusion resin. A packaging characterized in that the strip-shaped fusion bonding portion is provided with a rugged strip that is continuous in the length direction of the laminated film, where the sealing portion extends from the fusion bonding portion to the periphery of the packaging bag or the vicinity thereof. bag.