CA2045540A1

CA2045540A1 - Stand-up bag

Info

Publication number: CA2045540A1
Application number: CA002045540A
Authority: CA
Inventors: Rainer Wild
Original assignee: Individual
Current assignee: INDAG Gesellschaft fuer Industriebedarf mbH and Co Betriebs KG
Priority date: 1989-01-26
Filing date: 1990-01-25
Publication date: 1990-07-27
Also published as: WO1990008704A3; JPH04503345A; EP0380111A3; WO1990008704A2; IE900281L; EP0380111A2; EP0455675A1; DE8900883U1; IE900282L

Abstract

Abstract of the Disclosure The invention relates to a stand-up bag made of a heat-sealable or weldable plastic sheet material and adapted to contain liquid and/or pasty products.
In order to devise a stand-up bag of this type in such a manner that it retains sufficient stability or standing ability after its contents have been partially dispensed, that it is capable of being readily handled and conveyed as well as of being produced in a simple manner and requires minimum storage space in its empty state, the invention provides that the stand-up bag is provided with a dispensing opening defined by a spout made of a plastic sheet material and connected to the top wall element of the bag.

Description

~o~ss~o 1 Stand-Up Bag Description The invention relates to a stand-up bag having a dispensing 5 opening and made of a heat-sealable or weldable plastic sheet material, for containg liquid andtor pasty products, said bag comprising two sidewall-forming substantially rectangular flat sheet elements sealed to one another along their longitudinal margins, a foldable bottom element 10 acting as a support bottom and adapted to lie between said sidewalls being interposed between the lower trans~erse margins of said sidewalls, and a foldable sheet element acting as a top wall and adapted to lie between said side-walls being interposed between upper portions of said side-15 walls.
Stand-up bags made of plastic sheet material are specific-ally known as disposable beverage packages. Packages of this type usually terminate in a pointed end and have a filling volume of o.2 litres. The sheet material employed for these beverage packages is provided with a thin aluminum sheet layer serving amongst other purposes to stabillize the package. The bottom side is formed with a support bottom surface permitting the bag to be placed on a support after having been opened, without the danger of the bag's contents spilling from the dispensing openign or of the bag toppling over. In beverage packages of this type the dispensing opening may for instance be determined by a piercable weakened portion capable of being pierced by a drinking straw terminating in a pointed end.
Aside from beverages, sheet bags are also used for filling them with other liquid or pasty products, for instance liquid detergents. Sheet bags of this type are especially used as refill packages.
35 In order to impart increased stability to such stand-up bags comprising a lower bottom wall interposed between the sidewalls and preferably composed of two wall elements welded to one another, an additional top wall element is 2 20~5S40 1 included with a structure similar to that of the bottom wall.
The basic advantage of such sheet bags can be seen in the fact that they can be folded extremely flat in their empty state so as to require very little space. Particularly 5 stand-up bags of a greater volume, for instance a volume of up to two litres, are practically not used for containing products to be dispensed in individual portions, because after opening the bag as by cutting off an upper corner portion, it is not ensured that the bag retains sufficient 10 stability to remain standing when air enters its interior and the contents have been partially dispensed.
It is an object of the invention to provide a stand-up bag which is capable of retaining sufficient stability after its contents have been partially dispensed and of being readily handled and conveyed, which can be manufactured in a simple manner and requires little storage space in its unfilled state.
This object is attained according to the invention by the 20 provision that the dispensing opening is formed by a spout made of a plastic sheet material and connected to the top wall. The provision of a spout on the top wall portion of the stand-up bag defines the location of the dispensing opening to be recognized by the user; at the same time the 25 spout defines a dispensing opening for the bag's contents to be dispensed therethrough. A spout of this type can be readily made of a plastic sheet material and welded to the top wall likewise consisting of a plastic sheet material.
For opening the spout its upper end is cut off, it being 30 possible at that time to determine the size of the opening of the spout by selecting a suitable cutting angle. The spout even offers the additional possibility of closing the opening as by means of a spring clamp; for proper sealing of the opening, the spout may be folded in several 35 plies adjacent the clamping location.
In an advantageous embodiment of the stand-up bag the top wall is provided with a central folding seam extending between the two sealing seams of the sidewalls. The spout 3 ~45S4;Q
1 is then connected to the top wall along this folding seam, preferably at the center thereof, so that it is accurately located at thb center between the front and rear sidewalls.
In this case the top wall should be symmetric with respect 5 to its folding seam. The resulting symmetrical arrangement of the spout results in a very stable construction.
In order to permit the sealing seams required for the completion of the spout to be aligned in a common plane or line, respectively,, with a view on the one hand to 10 minimum space requirement in the folded state, and on the other hand, to an even distribution of traction forces in this plane or line, the top wall and the spout are made of two sheet elements each defining respective sidewall port-ions of the top wall and the spout. The correspondingly 15 cut sheet elements are sealed to one anotehr along their margins forming the folding seam and along the lateral edges of the spout. The upper edge, which is preferably used for defining the dispensing opening of the spout, may likewise be sealed. In a preferred embodiment this 20 sealed edge may also be obtaiend by the provision that the two sheet elements are connected to one another along this edge, i.e. that the two sidewall members are formed as an integral sheet element to be folded along this edge. The formation of the dispensing end in such a manner offers the 25additional advantage that only a narrow strip along this edge has to be removed, i.e. cut off, for opening the stand-up bag.
In the mass-production of the stand-up bag the spout may be made as a separate sheet element and sealed or welded to the top wall. In this manner it is possible to attach different spout as required to prefabricated stand-up bags of otherwise identical construction. Depending on the contents of the stand-up bag, such spouts may be rather narrow and long, or alternatively very short and wide, for instance in the shape of a trapeze.
Particularly when the edge of the spout defining the dispensing opening is formed as a sealing seam, it is 20~5540 1 advantageous to provide a pre-marked separation line permitting the user to cut the spout along this separation line for opening the stand-up bag. The length of the spout is preferably selected so that it projects above the upper 5 margins of the sidewalls, as a result of which the spout is readily accessible and permits the contents of the stand-up bag to be dispensed therefrom without problems.
In a preferred embodiment the spout of a filled stand-up bag is of frustoconical configuration.

For permitting the stand-up bag to be readily handled it is provided with grip openings formed in extended sidewall portions projecting above the top wall. These grip openings, in a readily producible embodiment in the form of punched slits, are readily accessible at their positions above the top wall. Also in this case the length of the spout is preferably selected so that it projects above the upper margins of the extended sidewall portions. The grip openings may be formed in a simple manner by punching the two side-walls at congruent locations in the folded state of the bag, so that the grip openings are positioned diametrally opposite each other in the filled state of the bag. For ensuring the uniform distribution of traction forces in the sidewalls adjacent the locations of the grip openings, 25 the latter may extend substantially parallel to the sealing seam of the top wall between the sidewalls and the top wall.
The stand-up bag including the spout is made of prefabric-ated heat-sealable flat sheet members, preferably of a 30 twin-layer compound sheet. Excellent properties are obtained by an inwards facing sheet of polyethylene and a polyester sheet forming the outer skin. The employ of a polyethylene sheet in the form of a coextrusion sheet - that is, a multiple-layer sheet - offers the advantage that the 35sheet forming the interior wall of the stand-up bag can be adapted to varying requirements in accordance with the intended use of the stand-up bag. It is thus for instance possible to select a particularly readily sealable 2~5s4~
l composition for the side of the sheet on which the sealed connections are to be formed; the composition of the coextrusion sheet may also be selected so as to obtain a higher degree of rigidity. The thickness of the outwards 5 facing polyester sheet is at least 10 ,um, and preferably 12 ,um, while the inwards facing polyethylene sheet or coextrusion sheet should have a thickness of 80 to 200 ~m, and preferably a thickness of 100 ~m to 150 ~m.
In order to permit the stand-up bag to also contain solvent-lO containing or migration-sensitive products, a thin aluminum sheet acting as a barrier layer may be enclosed between the individual sheet layers, preferably adjacent the inwards facing sheet layer, which aluminum sheet layer should have a thickness of between 8 ~um and 15 jum, depend-15 ing on the size of the stand-up bag. An aluminum sheet layer of this kind is effective for instance to prevent the leakage of solvents through the walls of the bag, or, in the case of migration-sensitive products, the infilt-ration of oxygen into the bag and thus into the product.

In order to impart the highest degree of stability or standing ability to the bag, it is advantageous when the bag assumes a substantially cylindrical shape in its filled state. For at~aining this objective, the two sidewalls are made in a rectangular shape and sealed to each other along ~heir longitudinal margins. The bottom wall element and the top wall elements are in this case formed as substant-ially circular cuttings. Both the bottom wall element and the top wall element are sealingly connected to the side-walls along respective semicircular sealing seams in the folded state of the bag. As an alternative to such rect-angular shape of the sidewalls or the cylindrical shape of the filled stand-up bag, respectively, the sidewalls may be designed to slightly converge towards the top wall element, resulting in a frusto-conical configuration of the filled stand-up bag. In order to make the spout readily accessible, it should preferably be located at the highest point of the upstanding filled bag.

55~0 1 An embodiment of the invention shall now be described in detail by way of example with reference to the accompanying drawings, wherein:
fig. 1 shows a perspective view of a filled stand-up bag, fig. 2 shows a stand~up bag similar to the one shown in fig. 1, illustrated in its empty and folded state, fig. 3 shows a longitudinally sectioned view of the stand-up bag of fig. 1, taken along a section line III'-III' as indicated in fig. 2, fig. 4 shows a sheet cutting for forming a spout defining a dispensing opening, and fig. 5 shows a sectional view of a plastic sheet material used in the manufacture of the stand-up bag.
As particularly shown in figs. 1 and 3, a stand-up bag has two sidewalls 1 heat-sealed to one another along their vertically extending longitudinal margins 2 by the form-ation of respective sealing or weld seams 3. Interposed 20 between sidewalls 1 adjacent their lower transverse margins 4 is a bottom wall element 5 acting as a standing support bottom and formed by a circular or elliptical cutting as clearly apparent from the bottom weld seam 6 depicted in fig. 2. Bottom wall 5 and sidewalls 1 are sealed or welded 25 to one another in full surface contact over the entire area between lower transverse margin 4 and bottorn weld seam 6, so that the thus obtain~ed two-layer plastic sheet forms a reinforced bag wall in this lower area.
In the filled state of the bag bottom wall 5 sags at least 30 at its central portion as indicated by the broken line 7 in fig. 3. The thus sag~ing bottom wall 5 cooperates with the reinforced lower transverse margins 4 to result in an excellent standing ability or stability of the stand-up bag.
All of the cuttings used for making the stand-up bag consist of a twin-layered plastic sheet material as shown in a sectional view in fig. 5. The outwards facing sheet 8 acting as the outer skin is a polyester sheet having a 2~ o 1 thickness of 12 um, whereas the sheet 10 facing towards the interior 9 of the stand-up bag and acting as the inner skin is a polyethylene sheet formed as a coextrusion sheet.
A coextrusion sheet of this kind is composed of several 5 layers resulting in a layered structure which may be varied during the extrusion process for adaptation to specific requirements. Sheet 10 has a thickness of 12 um, with the provision that the sheet thicknesses indicated above are applicable to a stand-up bag having a capacity 10 of about 1 to 1.5 litres, or a maximum capacity of 2 litres.
Enclosed between the sheet 8 acting as the outer skin and the sheet 10 acting as the inner skin is a thin aluminum sheet acting as a barrier layer 10' and having a thickness of between 8 and 12 um, depending on the size of the 15 stand-up bag. An aluminum layer 10' of this kind is effective for instance to prevent the leakage of solvents through the walls of the bag or, in the case of migration-sensitive products, the penetration of oxygen into the bag and thus into the product.
Z The stand-up bag has substantially cylindrical outer contours and is provided with a top wall element 11 of a shape similar to that of bottom wall element 5 and sealingly connected to respective upper portions of side-walls 1. By contrast to the bottom weld seam 6 of bottom 25 wall 5, the weld seam 12 of top wall element 11 extends along a circular path with its opening directed downwards, i.e. it extends in a direction opposite to that of the weld seam 6 of bottom wall 5. Both bottom wall 5 and top wall 11 are formed with a respective folding seam 13 30 extending between the weld seams 3 of sidewalls 1 as indicated in fig. 2.
Connected to top wall 11 along folding seam 13 is a spout 14 defining a dispensing opening 15 at its end. As shown in fig. 2, spout 14 is of conically converging configur-ation towards its free end, so that an opening of reduced cross-sectional area is formed by opening spout 14 along a separation line 16 provided by way of a marker. The length 8 ~ 5~
l of spout 14 is selected so that it projects above the upper transverse margins 17 of sidewalls 1 and is thus readily accessible. Spout 14 and top wall 11 are integrally formed of a one-piece cutting shown in fig. 4. In this 5 embodiment top wall 11 is composed of two rectangular flat elements of a width corresponding to that of side-walls 1. Extending from the central portion of a longer margin of these flat sheet elements are respective trapeze-shaped extensions joined at their narrow ends in a 10 mirror-image arrangement. The folding line indicated at 18 forms the edge 18 at the free end of the spout of the finished stand-up bag as shown in fig. 2. When using a sheet cutting of the kind shown in fig. 4, the end of spout 14 defining dispensing opening 15 needs not be 15 provided with a weld seam. The locations of,the weld seams of spout 14 and top wall element 11 are indicated by respective margin portione 19.
Sidewalls 1 are extended upwards above top wall 11, so that there remains a sufficient length of the sidewalls 20 for the formation of punched grip openings 20. In the collapsed and folded state of the stand-up bag, the grip openings 20 of sidewalls 1 are located at congruent locations, so that they can be formed in a single punching operation. While the grip openings 20 of the stand-upb bag 25 shown in fig. 2 are formed as horizontally extending elongate holes, the grip openings 20 of the stand-up bag shown in fig. 1 are formed as mere slits. The sheet portions separated by these slits are simply pushed aside when the stand-up bag is carried. The grip openings 20 30 are of an arcuate shape substantially corresponding to that of top weld seam 12. The sheet portions extending between top wall weld seam 12 and upper transverse margins 17 may likewise have a twin-layer structure formed by sidewalls 1 and the upwards folded marginal portions of the top wall 35 cutting 11 shown in fig. 4, to result in the reinforcement of the wall portions in which the grip openings 20 are formed.

Claims

Stand-Up Bag Patent Claims

1. A stand-up bag having a dispensing opening and made of a heat-sealable or weldable plastic sheet material, for containing liquid and/or pasty products, said bag comprising two sidewall-forming substantially rectangular flat sheet elements sealed to one another along their longitudinal margins, a foldable bottom element acting as a support bottom and adapted to lie between said sidewalls being interposed between the lower transverse margins of said sidewalls, and a foldable sheet element acting as a top wall and adapted to lie between said sidewalls being interposed between upper portions of said sidewalls, characterized in that said dispensing opening (15) is formed by a spout (14) made of a plastic sheet material and connected to said top wall (11).

2. A stand-up bag according to claim 1, characterized in that said top wall (11) has a central folding seam (13) extending between the two sealed seams (3) of said side-walls (1), said spout (14) being connected to said top wall along said folding seam (13).

3. A stand-up bag according to claim 2, characterized in that said top wall (11) and said spout (14) are formed of two sheet elements each of which forms one side portion of said top wall (11) and said spout (14), said sheet elements being sealed to one another along said folding seam (13) and along the edges of said spout (14).

4. A stand-up bag according to claim 3, characterized in that the sheet portions forming said spout (14) are integrally connected to one another along the edge (18) defining said dispensing opening (15).

5. A stand-up bag according to claim 2, characterized in that said spout (14) is formed of a separate sheet element and sealingly inserted into said top wall (11).

6. A stand-up bag according to claim 5, characterized in that said sheet element forming said spout (14) consists of two identical portions provided with a connection adjacent said edge (18) defining said dispensing opening (15).

7. A stand-up bag according to any of claims 1 to 6, characterized in that a separating line (16) is marked along the edge of said spout (14) defining said dispensing opening (15).

8. A stand-up bag according to any of claims 1 to 7, characterized in that the length of said spout (14) is selected so that it projects above the upper transverse margins (17) of said sidewalls (1).

9. A stand-up bag according to any of claims 1 to 8, characterized in that said spout (14) is of frusto-conical shape.

10. A stand-up bag according to any of claims 1 to 9, characterized in that said sidewalls (1) are extended above said top wall (11), the thus extended portions being formed with grip openings (20).

11. A stand-up bag according to claim 10, characterized in that said grip openings (20) are formed as punched slits.

12. A stand-up bag according to claim 10 or 11, charact-erized in that said grip openings (20) are formed at congruent locations of said sidewalls (1).

13. A stand-up bag according to any of claims 10 to 12, characterized in that said grip openings (20) extend sub-stantially parallel to the connection line (12) between said sidewalls and said top wall.

14. A stand-up bag according to any of claims 1 to 13, characterized in that said plastic sheet material is a twin-layer compound sheet (8, 10).

15. A stand-up bag according to claim 14, characterized in that the sheet (10) directed towards the interior (9) is a polyethylene sheet.

16. A stand-up bag according to claim 14 or 15, charact-erized in that the sheet forming the outer skin (8) is a polyester sheet.

17. A stand-up bag according to claim 15, characterized in that said polyethylene sheet is a coextrusion sheet.

18. A stand-up bag according to any of claims 11 to 17, characterized in that the outwards directed sheet (8) has a thickness of at least 10 µm.

19. A stand-up bag according to claim 18, characterized in that the thickness of the outwards facing sheet (8) is 12 µm.

20. A stand-up bag according to any of claims 14 to 19, characterized in that the inwards facing sheet (10) has a thickness of 80 µm to 200 µm.

21. A stand-up bag according to claim 20, characterized in that the thickness of the inwards facing sheet (10) is 100 µm to 150 µm.

22. A stand-up bag according to any of claims 1 to 21, characterized in that said bottom wall (5) and said top wall (11) are cut to a substantially circular shape and connected to said sidewalls (1) in such a manner that the filled bag forms a cylinder.

23. A stand-up bag according to any of claims 14 to 22, characterized in that an aluminum sheet (10') is enclosed between the two layers (8, 10) of said compound sheet.

24. A stand-up bag according to claim 23, characterized in that said aluminum sheet (10') has a thickness of between 8 µm and 15 µm.