EP2368706A1 - Method for producing a gusset bag - Google Patents

Abstract

The method involves forming front walls (2) and side folds (3) through folding of a bag foil such that side edges are formed as folding edges. The walls and the side folds are separated from each other at the folding edges. One of the walls is turned down with an upper section (10), and gripping lugs (11) and a reclosure unit (12) are arranged in a head area of a bag body before folding the section, where the head area is opened by turning down the upper section. Longitudinal sealed seams are formed at the folding edges after forming the walls and the side folds.

Description

Description:

The invention relates to a method for producing a side gusseted bag having two front walls, two gussets adjoining the front walls by side edges, a reclosure and two grip loops projecting with a central portion over a bag body formed by the front walls and side gussets and extending with their ends extend into the bag body at an upper edge of the front walls.

The sewn crease bag can be easily carried with the grip loops protruding from the top edge of the bag body, even with a very large weight. After a first opening the re-closure ensures protection of the packaged goods, so that this is still storable after removing only a subset. Also, the accidental, uncontrolled discharge of the contents can be safely avoided. The gusseted bag is particularly suitable for packaging large quantities of bulk goods such as pelleted pet food, detergent, cat litter, salt or powdery or granular building materials. Before opening for the first time, the gusseted bag is usually tightly sealed, which ensures good shelf life.

A method of manufacturing a side gusseted bag having two front panels, two side gussets adjoining the front panels by side edges, a reclosure and two handle loops projecting with a central portion over a bag body formed by the front panels and gussets and terminating in an upper panel Reach the edge of the front walls in the bag body, is from the WO 2005/113357 A1 known. In the known method, the preformed handle loops are introduced between two parallel-guided film layers. In addition to the Handle loops are also supplied portions of a film tube for forming the gussets and a film section to form a bottom fold. Subsequently, a strand is formed by the sealing of the supplied elements, can be separated from the individual side gusseted bag. The supply of individual film sections is expensive, with an accurate positioning and heat sealing is necessary.

Against this background, the invention has for its object to provide a method with the features described above, which is easy to perform, in particular, the number of supplied components to be reduced.

Object of the invention and solution of the problem is a method according to claim 1.

According to the invention, the two front walls and the two side folds are formed by folding a bag film such that at least three of the four side folds are formed as folded edges. Subsequently, at least one folding edge, the local front wall and gusset are separated starting from the upper edge over a partial length of the folding edge and then folded over one of the front walls with an upper portion to itself. Then, the handle loops and the re-closure are arranged in a by folding over the upper portion of the exposed head portion of the bag body, before the upper portion is folded back again. Usually, the side fold and the front wall, which are separated from one another in the head area, are again closed by a longitudinal sealing seam in order to ensure complete sealing of the corresponding side edge. According to the present invention, the entire bag body is formed with the two front walls and the two gussets of a single bag film section. Only after the formation of the initially not yet closed bag body, the handle loops and the reclosure are arranged. For this purpose, however, the inner surface of the bag body must be exposed, including one of the front walls is folded over with an upper section to itself. For this to be possible, the corresponding front wall must be separated from the two adjoining gussets at the top section to be folded. In the formation of the bag body from the bag film, the edges of the bag film can be placed on one another at one of the side edges, so that then only the three remaining side edges are formed as folded edges. In order to be able to fold back one of the front walls, at least one of these folded edges must be separated in the head area accordingly. If all four side edges are formed as folded edges and the edges of the bag film are brought together at another location, for example one of the front walls, at least two of the folded edges in the head area must be correspondingly separated.

According to a preferred embodiment of the invention, the local front wall and side fold, starting from the upper edge, are separated from each other over a partial length of the folded edge at all folded edges. This allows not only a folding one of the front walls, but also a folding of the gussets. This results in the advantage that the still flat front wall is completely accessible, wherein the folded front wall and the folded side folds do not hinder the arrangement of the handle loops and / or the arrangement of the reclosure.

In order to enable a separation of the front walls and the side folds at the folded edges, can be provided in the context of the method according to the invention be previously formed longitudinal sealing seams, which save the head area. Subsequently, an outer edge is cut off at the side edges, so that at the folding edges, the respective front wall is separated from the associated side fold in the head area kept free by longitudinal sealing seams. Below the head area, the front wall and the side fold remain connected by the previously produced longitudinal sealing seam.

The exact nature and sequence of the arrangement of the handle loops and the re-closure in the exposed head area is not limited in the invention.

Conceivable, for example, folding only a front wall, then successively a first handle loop between the unfolded gussets, the reclosure on the first handle loop and then the second handle loop on the reclosure can be interpreted before the folded front wall folded back and the arrangement by a Cross-seam seam is fixed.

According to an alternative embodiment of the method according to the invention, one of the grip loops with its ends on the inner surface of the not folded on itself front wall hang up and at least vorzufixieren, hang up the other handle loop with their ends on the inner surface of the folded upper portion of the other front wall and at least pre-fix and to place the reclosure on one of the front walls and / or at least one of the gussets before the upper portion with the then at least prefixed handle loop is folded back again.

Furthermore, it is also possible to pre-fix the two gripping loops on the reclosure before the gripping loops are arranged with the reclosure as a prefabricated arrangement in the head region of the bag body. The prefixing can be done for example by gluing or welding points. If the gripping loops are fastened with the reclosure as a prefabricated arrangement or if the two gripping loops and the reclosure are fastened successively to only one of the two front walls, there is the advantage that the arrangement on only one side results in subsequent filling of the bag at its upper end Edge is facilitated. If in the context of the variants described, the reclosure over its entire length is first attached to only one of the front walls and if the connection of reclosure with the gussets takes place only after filling the gusseted bag, there is the advantage that for filling in the head region of the bag body also the gussets can still be spread, whereby a larger filling opening can be provided. Even with such an embodiment, the grip loops either can be arranged with the reclosure on one of the front walls or as previously described on both front walls.

In order to provide a large removal opening of the side gusseted bag, a reclosing perpendicular to the folded edges is preferably applied, which is so long that it completely covers the front walls between the gussets and at least partially overstays the gussets themselves. Especially when the reclosure also extends in the area of the gussets, it is advantageous to shorten these at their upper end, so that the shortened gussets are completely covered at their upper end by the reclosure.

The Wiaderverschluss is preferably arranged so that it also covers the ends of the handle loops. The handle loops are then each sealed on one side to one of the front walls and on the opposite side to the reclosure, whereby a uniform load distribution and increased load capacity can be achieved.

The Seitenfaftenbeutel is initially open either at its top or bottom, to be filled later. After filling, this is then expediently hermetically sealed.

In order to be able to form the two front walls and the two side folds from the bag film by folding, it is preferably first moved in a first direction parallel to the generated side edges. Subsequently, when the reclosure and the handle loops are attached, the bag blank can be transported perpendicular to the side edges, wherein due to the separate process steps a cyclic movement is preferred. By folding the bag film, a long film tube is usually first formed, from which individual bag blanks are then cut off with an unlocked bag body formed from the front walls and the side folds.

In order to ensure good handling of the side gusseted bag and this also can be formed by folding a floor stand on the bottom of the bag body.

The reclosure preferably has interlockable profile strips. In particular, interlocking profile strips can be provided, which can be separated from each other by a slider in the manner of a zipper and connected to one another. In order to operate the slide easily, this should with the profile strip above the upper edge of the bag are arranged, wherein the attachment of the reclosure then takes place via terminal lugs, which extend from the profile strips into the bag body and are festgesiegeft on the inside of the bag. These terminal lugs can be used in particular to close the upper ends of the gussets tightly, if they have been previously shortened. The reclosure is expediently provided with a tamper-evident closure. Thus, for example, in the case of the reclosure described above with a slider, the ends of the connecting lug arranged within the bag body can be separably connected to one another. In the context of the invention, there is the advantage that this separation can be produced in a particularly simple manner by pulling apart the grip loops with sufficient force when the profile strips are separated from one another. The tamper-evident closure is intended both to initially ensure a particularly tight closure of the bag and to indicate to the user that there is no manipulation of the contents.

The bag film is usually multilayered, wherein the outer surface of the bag body is not or only with difficulty heat sealable. Such a multilayer bag film preferably comprises a heat sealable layer of polyolefin on the inner surface of the bag body. For example, laminated or coextruded films having an outer surface of polyethylene terephthalate (PET) and an inner surface of polyethylene (PE) are suitable. Between the inner layer and the outer layer without further film layers, for example, arranged to increase the stability and / or the barrier effect. In the case of a laminated film, it is also possible in particular to use a metallic layer or a metallized plastic layer, for example metallized PET. Also composite materials with an outer layer of oriented polypropylene (O-PP) or with Layers of different types of polyethylene, for example a PE / PE laminating composite, can be used in the context of the invention, wherein the polymer composition is expediently selected so that only the inner surface melts at a suitable sealing temperature. Bag films made entirely of polyolefins are characterized by a good recyclability.

The layer thicknesses of the heat-sealable polyolefin layer are typically between 50 and 150 μm. Depending on the material, a significantly smaller layer thickness is sufficient for the film layer which forms the outer surface of the bag body. The thickness of this film layer is usually between 10 and 100 .mu.m, with materials such as PET or O-PP particularly preferably between 10 and 30 .mu.m.

The handle loops must be heat-sealable in order to be able to be attached at least to the front walls. If the handle loops are sealed in accordance with a preferred embodiment between the front walls and the reclosure, they must be heat sealable on both sides. In order to achieve a high load capacity, a sufficient material thickness is to be provided in the grip loops. In particular, the handle loops can also be folded onto itself in the manner of a flattened tube and fixed by heat sealing. In addition to single or multilayer films of polyethylene (PE) with a typical thickness between 100 .mu.m and 400 .mu.m, it is also possible to provide stiffer intermediate layers with an increased carrying capacity, for example polyamide (PA) or PET. In a three-layered embodiment with PE outer layers and an intermediate layer of PA or PET, the total thickness is typically between 100 and 200 μm.

A particularly comfortable handling results when the handle loops have a substantially straight central portion, from which the ends are angled.

Fig. 1 bis 6

die Verfahrensschritte zur Herstellung eines Seitenfaltenbeutels in einer zweckmäßigen Reihenfolge;

Fig. 7

die Befestigung von Griffschlaufen und eines Wiederverschlusses gemäß einer Variante des Verfahrens.

The invention will be explained in the following with reference to a drawing showing only one exemplary embodiment. Show it:

Fig. 1 to 6

the process steps of producing a gusseted bag in a convenient order;

Fig. 7

the attachment of handle loops and a reclosure according to a variant of the method.

According to the Fig. 1 is first formed from a bag film 1 by folding a tube with front walls 2 and arranged therebetween side pleats 3. The edges of the bag film are superimposed on one of the side edges 4 between the front walls 2 and the gussets 3. The remaining side edges 4 'are formed as folded edges. After the side gusseted tube has been formed, longitudinal sealing seams 5 with interruptions 6 are produced on the side edges 4, 4 '. Subsequently, an outer edge 7 is severed at the side edges 4, 4 ', whereby the front walls 2 are separated from the respective subsequent side folds 3 in the region of the interruptions 6 at the side edges 4' designed as folding edges. Subsequently, individual not yet closed bag body 8 are separated so that the interruptions 6 each extend in a head portion 9 of the bag body 8.

In the formation of the front walls 2 and the gussets 3, the bag film 1 is moved in a first direction parallel to the side edges 4, 4 'formed. at the further procedural steps, the transport of the bag body 8 is preferably perpendicular to the side edges 4, 4 '.

According to the Fig. 2 For example, in one of the front walls 2, an upper portion 10 is folded over, exposing the side of the bag film 1 forming the inner surface of the bag body 8 in the head portion 9. According to the described embodiment of the method, the two side folds 3 are folded, so that the unfolded front wall 2 is freely accessible.

According to the Fig. 3 a handle loop 11 is placed with its ends on the inner surface of the not folded on itself front wall 2 and at least pre-fixed.

According to the Fig. 4 Then the gussets 3 are folded back, the side gussets 3 are shortened at its upper end.

In a subsequent method step, a reclosure 12 is placed on the unfolded front wall 2 and the already folded back side gussets 3 and at least pre-fixed. The reclosure has interlockable profile strips 13, a slider 14 and terminal lugs 15. The profile strip 13 and the slider 14 extend beyond the upper edge 16 of the front walls 2, wherein the terminal lugs 15 rest on the gussets 3 and between them on the front wall 2 and already arranged there grip loop 13, By shortening the gussets 3 these sealed by the terminal lug 15 by heat sealing. Of the Fig. 5 , which shows this arrangement, it can be seen further that at the folded upper portion 10 of the other front wall 2, a further handle loop 11 is placed and at least pre-fixed has been. The laying on of the second handle loop 11 can take place before, simultaneously with or after the arrangement of the reclosure 12. In the detail of the Fig. 5 is also a transverse sealing seam 17 shown, with which one of the terminal lugs 15 is attached to the associated front wall 2 and the gussets 3.

Finally, the upper portion 10 is folded back with the Griffschiaufe 11 attached thereto, in which case the front walls 2 and gussets 3 separated from each other in the head area 9 are connected by longitudinal sealing seams 5 '. The longitudinal sealing seams 5 'produced in this method step form, with the previously produced longitudinal sealing seams 5, a continuous, sealed seal (FIG. Fig. 6 ).

Usually, the gusseted bag is closed by a transverse seal, not shown, either at its upper or lower end. A complete closure takes place only after filling the gusseted bag. This filling can be done either by an opening at the top, that is, in the illustrated embodiment, an opening between the reclosure 12 and the previously folded front wall 2. In addition, the gusseted bag can also be filled over the floor, especially if the provided at the top grip loops 11 are obstructive in the filling.

That in the Fig. 2 and 3 shown capping the gusset 3 is only optional.

Unlike in the Fig. 5 shown, the last arranged handle loop 11 can also be placed directly on the reclosure 12 and pre-fixed. It then results in the advantage that both handle loops 11 and the Reclosure 12 are attached to the upper edge 16 only on one side, whereby a filling of the not yet sealed bag body 8 is facilitated from the top.

This advantage is also achieved if, according to a variant of the method, the grip loops 11 are first pre-fixed to the reclosure 12 before the grip loops 11 with the reclosure 12 are arranged as a prefabricated arrangement in the head region 9 of the bag body 8. Such an embodiment of the method is in the Fig. 7 shown.

In order to expose the bag film 1 in the head region 9, the upper section 10 of one of the front walls is folded over. According to a further variant of the method, it is provided that the reclosure 12 extends over its entire length only to one of the front walls 2 but not to the side folds 3 is hung up. This can be accomplished by attaching the reclosure 12 to the upper portion 10 of the folded front panel 2 while not folding the side pleats 3 or by attaching the reclosure 12 to the non-self-folded flat-faced front panel 2 while the reclosure 12 is secured Gussets 3 with the upper portion 10 are folded with.

Thus, for example, in an arrangement according to the Fig. 7 the upper sections of the gussets 3, as in Fig. 2 and Fig. 3 shown, are folded before the prefabricated assembly with the two handle loops 11 and the reclosure 12 is placed.

Furthermore, it is also possible in a modification of the in Fig. 4 and Fig. 5 shown method steps to fold back the gussets 3 only after the arrangement of the reclosure 12. Even then it is achieved that the Re-closure 12 is attached over its entire length initially only on one of the front walls 2 and not on the gussets 3, whereby they can be spread for filling.

A seal on both sides and a connection of the reclosure 12 with the gussets 3 is then preferably carried out after filling by a transverse sealing seam extending over the width of the gusseted bag.

Claims (15)

Method for producing a side-fangulated bag having two front walls (2), two side folds (3) adjoining the front walls (2) via side edges (4, 4 '), one reclosure (12) and two grip loops (11) having a central section via a bag body (8) formed by the front walls (2) and the gussets (3) projecting and with their ends at an upper edge (16) of the front walls (2) in the bag body (8) extend, wherein successively by folding a bag film (1) the two front walls (2) and the two side folds (3) are formed in such a way that at least three of the four side edges (4, 4 ') are formed as folding edges, on at least one fold edge, the front wall (2) and side fold (3) are separated from one another over a partial length of the fold edge, starting from the upper edge (16), - One of the front walls (2) with an upper portion (10) is folded over on itself, and - The handle loops (11) and the reclosure (12) in a by the folding of the upper portion (10) exposed head portion (9) of the bag body (8) are arranged before the upper portion (10) is folded back again. A method according to claim 1, wherein at all the fold edges the local front wall (2) are separated from the side fold (3) starting from the upper edge (16) over a partial length of the fold edge. Method according to claim 1 or 2, wherein after the formation of the front walls (2) and the side folds (3) and before the front wall (2) and the side fold (3) are separated on at least one folded edge on the side edges (4, 4 '). Longitudinal sealing seams (5) are formed, which save the head area (9). Method according to claim 3, wherein an outer edge (7) is cut off at the side edges (4, 4 '), so that at the folded edges the front wall (2) in the head area (9) kept free of the longitudinal sealing seams (5) of FIG associated gusset (3) is separated. Method according to one of claims 1 to 4, wherein during the arrangement of the handle loops (11) and the reclosure (12) in the exposed head region (9) - One of the handle loops (11) is placed with its ends on the inner surface of the non-folded on itself front wall (2) and at least pre-fixed, - The other handle loop (11) is placed with its ends on the inner surface of the folded-over upper portion (10) of the other front wall (2) and at least pre-fixed, and - The reclosure (12) on one of the front walls (2) and / or at least one of the gussets (3) is placed. Method according to one of claims 1 to 4, wherein during the arrangement of the handle loops (11) and the reclosure (12) in the exposed head portion (9) one of the handle loops (11) and then the reclosure (12) on one of the front walls (2) be arranged before the other Grip loop on reclosure (12) and then fold back upper section (10). Method according to one of claims 1 to 4, wherein the handle loops (11) are pre-fixed to the reclosure (12) before the handle loops (11) with the reclosure (12) arranged as a prefabricated assembly in the head region (9) of the bag body (8) become. Method according to one of claims 1 to 7, wherein the gussets (3) are shortened at their upper end. Method according to one of claims 1 to 8, wherein after the separation of the front walls (2) from the gussets (3) in the head region (9) also upper gusset sections are folded over and folded back in a later method step. Method according to claim 9 and one of claims 5 or 6, wherein the upper gusseted sections are folded back after the corresponding grip loop (11) has been placed on the inner surface of the non-self-folded front wall (2) and at least pre-fixed and before the reclosure ( 12) is placed. A method according to any one of claims 1 to 10, wherein a reclosure (12) extending perpendicularly to the side edges (4, 4 ') is applied, which is long enough to complete the front walls (2) between the gussets (3) and Gussets (3) itself at least partially spanned. Method according to one of claims 1 to 11, wherein the handle loops (11) are each sealed with their ends on one side on one of the front walls (2) and on the opposite side on the reclosure (12). Method according to one of claims 1 to 12, wherein the gusseted bag is sealed airtight after its filling through an opening at the top or bottom. Method according to one of claims 1 to 13, wherein the bag film (1) in the formation of the front walls (2) and the side folds (3) in a first direction parallel to the generated side edges (4, 4 ') is moved and wherein subsequently Movement of the bag blank perpendicular to the side edges (4, 4 ') takes place. Method according to one of claims 1 to 14, wherein a floor is formed by folding on the bottom of the bag body (8).

Images