Packaging bag

Abstract

The invention relates to a packaging bag with a back part (1) and a front part (2, 2a, 2b) which are connected to each other at the lower end (3) and at the sides (4) and which form a closable opening at their upper end region in that the back part (1) projects upwards over the upper end of the front part (2), wherein the projecting area (1a) of the back part (1) forms a flap (5) which can be folded over onto the front part (2) and can be bonded to the front part (2) by means of an adhesive strip (6), and wherein the front part (2) and back part (1) are made entirely of paper, wherein the flap (5) is multi-layered.

Description

[0001] The invention relates to a packaging bag with a back part and a front part, which are connected to one another at the lower end and at the sides and which form a closable opening at their upper end region in that the back part projects upwards beyond the upper end of the front part, wherein the projecting region of the back part forms a flap which can be folded over the front part and adhesively connected to the front part by means of at least one adhesive strip, and wherein the front part and back part are formed entirely from paper.

[0002] Such packaging bags are well known in the art and are typically used to package all kinds of goods, especially food. Paper envelopes also constitute such a packaging bag. One such envelope is known, for example, from US Pat. No. 5,713,511.

[0003] The front and back sections are preferably flat elements, each formed as at least one sheet, particularly made of paper, which define the volume between them that can be filled with a product. The connection on three sides forms a pouch pocket that is open at the top.

[0004] The connection can be achieved, for example, by applying an adhesive between the facing inner surfaces of the front and back panels in the edge area on the opposite sides and / or the lower end, or by folding one of the front or back panels onto the other with an adhesive interposed in such an edge area. The connection can also be achieved by means of a fold, e.g., a W- or Z-shaped fold in at least one of the two panels.

[0005] Preferably, in the invention, the connection on the opposite sides is formed by an adhesive between the opposite inner surfaces and the connection at the lower end by the back part being folded over and glued onto the front part.

[0006] The opposite sides are understood to be the areas of the bag that extend opposite each other from the lower closed end towards the upper sealable end.

[0007] Such packaging bags, in which the front and back parts are made of paper, are particularly environmentally friendly and sustainable. Paper is preferably understood to be a flat material made of bonded natural fibers, in particular cellulose fibers. According to the invention, the front and back parts are each formed from at least one sheet of paper.

[0008] However, such packaging bags have the disadvantage that the adhesive bond between the flap and the front part of the bag either cannot be removed again or at least cannot be removed without causing damage.

[0009] This is usually not a problem, as such paper packaging bags are often used only as disposable packaging. However, there is a growing need for this type of packaging bag to be reusable, especially multiple times. For example, when packaging clothing, which is frequently returned after being ordered from online retailers and then needs to be offered again in the original packaging bag.

[0010] However, this is not possible with the previous packaging bags, since these are at least partially damaged when the adhesive between the flap and the front part is opened, e.g. because the flap tears or partial areas, in particular paper fibers, are torn out of the surface in contact with the adhesive and continue to cover the adhesive, so that the adhesive no longer adheres to these areas.

[0011] It is therefore an object of the invention to provide a packaging bag made of paper which offers the possibility of being closed, opened and resealed in an adhesive manner, in particular adhesively, multiple times, preferably without any visible or even functionally impairing destruction of the packaging bag, in particular on the flap or on the at least one adhesive trace.

[0012] This object is achieved by a packaging bag according to claim 1.

[0013] The multi-layer design, which means at least two layers, increases the strength of the flap, allowing the flap to be removed from the front part by removing the adhesive bond, particularly while the adhesive trace remains on the packaging bag without damaging the flap. The risk of the flap tearing during the process of removing the adhesive bond is significantly reduced, and preferably eliminated, by the multi-layer design.

[0014] The multi-layered design of the flap is provided at least in the portion of the flap that covers the at least one adhesive line. Preferably, the flap is multi-layered in the entire area that can be folded over onto the front part, in particular with the exception of an area adjacent to the fold line.

[0015] The multi-layer structure of the flap can be achieved by various measures.

[0016] Preferably, in one possible embodiment, it is provided that the projecting area of the back part forming the flap is folded over at least once in the direction of itself and glued, in particular the opposing surface areas of the folded over projecting area are adhesively connected, preferably over the entire surface or at least in the predominant part of the opposing surfaces.

[0017] According to the invention, a reinforcing strip made of paper is inserted into the fold, preferably a single fold. The reinforcing strip is glued on both sides to the portions of the protruding area forming the flap. The folded and opposing surface areas of the protruding area forming the flap are thus indirectly adhesively bonded to one another via the reinforcing strip.

[0018] Preferably, the reinforcement strip extends across the entire width of the flap. The width direction is the direction in which the joined sides face each other.

[0019] Even if the protruding area is folded only once towards itself, a 3-layer flap with a very high strength is achieved compared to a conventional single-layer flap, particularly due to the bonding of all layers in the flap by gluing.

[0020] In a preferred refinement, it can be provided that the reinforcement strip, which is preferably also made of paper, has a different grammage, in particular a higher grammage, than the back part, in particular also than the front part. Likewise, a reinforcement strip can have the same grammage as the back part or reinforcement part, in particular be made of the same material as the back part or front part.

[0021] As an alternative to a reinforcing strip made of paper, the reinforcing strip can also be made of a fabric, in particular a fabric having meshes, or of a nonwoven fabric made of fibers, preferably natural fibers, and can be inserted by gluing between the partial areas of the flap folded over onto themselves.

[0022] The multi-layer structure can also be achieved by gluing at least one strip of paper, separate from the back part, onto the projecting area forming the flap.

[0023] The at least one adhesive trace used to bond the flap and the front part can be arranged either on the front part in the area of the front part that can be covered by the flap or on the flap itself, the former being preferred.

[0024] In a preferred development, it is provided that at least one adhesive trace is arranged on the front part on the area that can be covered by the tab and the tab is coated with a release agent at least in the area that contacts the at least one adhesive trace.

[0025] Alternatively, at least one adhesive track can be arranged on the side of the tab opposite the front part and the front part is coated with a release agent in the area that can be covered by the tab and that contacts the at least one adhesive track.

[0026] Such a release agent preferably has the property that the adhesive connection between the at least one adhesive trace and the surface of the tab or front part adhering thereto can be released more easily, in particular because the release agent reduces the adhesion between the adhesive and the surface of the tab or front part contacting it, which is understood to mean that the adhesive force between the adhesive trace and the adhering surface with the release agent coating is lower than for the same surface without the release agent.

[0027] Preferably, it can be provided that the release agent reduces the adhesion to a detachment force between the adhesive trace and the adhering surface of less than 1 Newton per 1 centimeter of adhesive trace length, more preferably less than 0.75 Newton per 1 centimeter of adhesive trace length, even more preferably less than 0.5 Newton per 1 centimeter of adhesive trace length.

[0028] Furthermore, the release agent preferably has the property of strengthening and / or smoothing the surface of the tab or the front part, e.g. by the fibers in the surface being bound more firmly to one another and / or being covered by the release agent.

[0029] When the flap is opened, there is less or preferably no fiber detachment from the surface of the flap or front part that adheres to the adhesive track and contacts the adhesive. This reduces or preferably prevents the progressive destruction of the surface that occurs with increasing number of openings, and the adhesive strength of the adhesive track is maintained, as no residue from the adhesive surface remains on it.

[0030] The release agent is preferably a varnish applied to the surface of the tab or front part that comes into contact with the adhesive trace.

[0031] Preferably, the invention achieves that the connection between the at least one adhesive trace and the surface of the tab or the front part adhering thereto can be detached and restored at least 10 times, preferably at least 100 times, at least essentially non-destructively.

[0032] Furthermore, in all embodiments it can be provided that the front part is folded over on itself at least once at its upper edge facing the opening, preferably in an area above the at least one adhesive trace, in particular the fold is glued.

[0033] This fold thickens the edge of the front part directly adjacent to the opening, reducing the risk of a user cutting themselves on the edge when removing or inserting goods into the packaging bag. Additionally, a thickening element, such as a thread, preferably made of natural fibers, can be inserted into the fold, particularly near the fold line, which further thickens the edge.

[0034] Furthermore, in all embodiments it can be provided that the front part and / or the back part has a translucent or transparent area, in particular made of tracing paper, preferably glassine.

[0035] For example, the front part can have a first upper partial region adjacent to the opening and a second partial region adjacent to the lower end, wherein the second partial region is preferably transparent across its entire width and is made of glassine. The partial regions can be arranged overlapping at their edges, particularly those parallel to the upper and lower ends, and glued together in the overlapped region.

[0036] In all embodiments, the back part can preferably be folded and glued at the lower closed end onto a region of the front part that is folded over onto itself, in particular to stabilize the lower closed end.

[0037] A preferred embodiment of a packaging bag according to the invention is shown in Figure 1 described.

[0038] The Figure 1shows a packaging bag according to the invention with a back part 1 and a front part 2. In the view shown, which shows a normal position of use, the front part 2 lies in front of the back part 1. At the lower end, as well as on the two opposite sides or edges 4, the front part 2 and back part 1 are connected to one another, here on the sides 4 preferably by an adhesive being inserted between the contacting inner surfaces of the front part 2 and back part 1. At the lower end 3, the back part 1 is folded forward onto the front part 2. The front part 2 can itself also be folded over here, so that the folded over part of the back part 1 then lies on the folded over part of the front part 2, in particular on its actual inner surface.In this case, the folded part of the back part 1 is preferably higher than the folded part of the front part 2, so that this part of the back part 1 which is folded forward also contacts the outer surface of the front part 2 via its folded part and is glued thereto.

[0039] At the upper end of the packaging bag, it has a closable opening that can be closed with a flap 5 formed from a portion 1a of the back part 1 that projects upwards beyond the front part 2. The flap 5 can be folded forward onto the front part 2 along a line shown here in dashed lines and then covers the opening.

[0040] The closed flap 5 covers an area of the front part 2, which in this embodiment has an adhesive track 6, which preferably extends across the entire width, i.e., between the sides 4. The flap 5 is thus held adhesively in place in the closed state because its side facing the front part 2 forms a surface adhering to the adhesive track 6.

[0041] According to the invention, the front part 2 and the back part 1 are made of paper.

[0042] In order to ensure frequent opening and reclosability, the flap 5 is constructed in multiple layers. In the case shown here, the flap 5 is three-layered. This is achieved by folding the protruding area 1a of the back part 1 back on itself. As a result of the fold, two of the three layers are formed by the protruding area 1a itself. A separate reinforcing strip 7 is additionally inserted into the fold, forming the third, middle layer of the three-layer flap 5. All layers of the flap 5 are glued to one another according to the invention. The flap 5 is thus significantly more stable than a conventional single-layer design and can thus be detached from the adhesive track 6 several times without being damaged.

[0043] In order to further reduce adhesion and improve the strength of the fiber composite of the paper fibers in the adhesive surface of the flap 5, the invention preferably provides that the flap 5 is coated with a release agent 8, at least in the area contacting the adhesive track 6, optionally also completely or over a larger area. Such a release agent can be applied, for example, by spraying, similar to painting. This makes it even easier to break the bond between the flap 5 and the front part 2, and the adhesive track 6 remains free of residues from the surface of the flap 5.

[0044] Such a packaging bag can therefore be opened and resealed many times.

[0045] Before the first sealing, the adhesive track 6 can be protected with a cover strip 9, which is removed for sealing.

[0046] The front part 2 is preferably formed in two parts. It comprises a non-transparent paper part 2a and a transparent paper part 2b, which is made of glassine, for example. Any goods in the packaging bag can thus be seen.

Claims

1. Packaging bag having a rear part (1) and front part (2, 2a, 2b), which are connected to one another at the lower end (3) and at the sides (4) and which form a closable opening at their upper end region in that the rear part (1) projects upwards beyond the upper end of the front part (2), wherein the projecting region (1a) of the rear part (1) forms a tab (5) which is able to be folded over onto the front part (2) and is able to be connected adhesively to the front part (2) by means of an adhesive line (6), and wherein the front part (2) and the rear part (1) are formed completely from paper, characterized in that the tab (5) is of multi-layer form, for which purpose the projecting region (1a) of the rear part (1) that forms the tab (5) is folded over at least once in the direction of itself and adhesively bonded and a reinforcing strip (7) composed of paper is placed into the fold, preferably into a single fold, said reinforcing strip being adhesively bonded on both sides to the subregions (5a, 5b) of the projecting region (1a) that form the tab.

2. Packaging bag according to Claim 1, characterized in that the reinforcing strip (7) extends over the entire width of the tab (5).

3. Packaging bag according to Claim 2, characterized in that the reinforcing strip (7) has a different grammage, in particular a greater grammage, than the rear part (1), in particular than the front part (2) too.

4. Packaging bag according to one of the preceding claims, characterized in that at least one adhesive line (6) is arranged on the front part (2) on the region able to be covered by the tab (5) and, at least in the region which makes contact with the at least one adhesive line (6), the tab (5) is coated with a release agent (8), or at least one adhesive line (6) is arranged on that side of the tab (5) which is situated opposite the front part (2) and, in the region able to be covered by the tab (5) that makes contact with the at least one adhesive line (6), the front part (2) is coated with a release agent (8).

5. Packaging bag according to one of the preceding claims, characterized in that the connection between the at least one adhesive line (6) and that surface of the tab (5) or of the front part (2) which adheres to said adhesive line is able to be released at least substantially without destruction and re-established at least 10 times.

6. Packaging bag according to one of the preceding claims, characterized in that the front part (2) is folded over at least once onto itself, in particular is adhesively bonded in the fold, at its upper edge (2c), which is directed towards the opening, preferably in a region above the at least one adhesive line (6).

7. Packaging bag according to one of the preceding claims, characterized in that the front part (2) and / or the rear part (1) have / has a translucent or transparent region (2b), in particular composed of transparent paper, preferably of glassine.

8. Packaging bag according to Claim 7, characterized in that the front part (2) has a first, upper sub-region (2a), which adjoins the opening, and a second sub-region (2b), which adjoins the lower end, wherein the second sub-region (2b), preferably over the entire width thereof, is transparent, in particular is formed from glassine.

9. Packaging bag according to one of the preceding claims, characterized in that, at the lower, closed end (3), the rear part (1) is folded onto a region of the front part (2) that is folded over onto itself, and is adhesively bonded thereto.

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