Pouch

Abstract

A flexible pouch, filled with a flowable product has a front pouch wall joined to a rear pouch wall along opposite side edges and along a bottom edge. The front pouch wall, when flat, has a first width at a first level above the bottom edge and concave or oblique opposite sides between the first level and the bottom edge so that a width of the front pouch wall progressively decreases below the first level, at least down to a second level. In consequence, when the pouch is set down with the bottom edge on a flat surface, the sides between the first level and the bottom edge collapse to provide a stable basal platform for the pouch.

Description

BACKGROUND OF INVENTION

[0002] This invention relates to a flexible plastic pouch containing a flowable product, such as a fluid.

[0003] Products may be packaged in flexible pouches as it minimizes the use of packaging material. However, where the product is flowable (such as a granulated product or a liquid), it may be advantageous to design the pouch so that it is self-standing.

[0004] It is known to produce a self-standing flexible pouch by utilising additional layers of packaging material, as, for example by gussetting the base of the pouch. This, however, increases the use of packaging material and manufacturing complexity. In another approach, after establishing seals to form the basic pouch, cross-seals are formed in a secondary operation to make the pouch self-standing. For example, in U.S. Pat. No. 6,164,042 to Tobolka, after sealing two sheets of plastic material together to form a liquid filled pouch, the bottom corners of the pouch are pinched flat to form triangular portions. A heat seal is then made along the base of the triangular portions and these triangular portions are then removed. This creates a rectangular base for supporting the pouch in a stand-up position. However, this intrusion into the previously formed pouch in order to form the triangular portions risks interfering with the integrity of the pouch.

[0005] A need remains for a robust self-standing pouch which is of simple manufacture.

SUMMARY OF INVENTION

[0006] In the present invention, the bottom portion of a flexible pouch is configured such that it collapses when on a flat surface to form a stable basal platform for the pouch.

[0007] According to the present invention, there is provided a flexible pouch, filled with a flowable product having a front pouch wall joined to a rear pouch wall along opposite side edges and along a bottom edge. The front pouch wall, when flat, has a first width at a first level above the bottom edge and concave or oblique opposite sides between the first level and the bottom edge so that a width of the front pouch wall progressively decreases below the first level, at least down to a second level. In consequence, when the pouch is set down with the bottom edge on a flat surface, the sides between the first level and the bottom edge collapse to provide a stable basal platform for the pouch.

[0008] Other features and advantages of the invention will become apparent from a review of the following description in conjunction with the figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In the figures which disclose example embodiments of the invention,

[0010] FIG. 1 is a perspective view of a pouch filled with a flowable product made in accordance with this invention,

[0011] FIG. 2 is a front view of the pouch of FIG. 1,

[0012] FIG. 3 is a front view of the pouch of FIG. 1, when empty,

[0013] FIG. 4 is a cut-away view showing a portion of the pouch of FIG. 1 during a pouch opening operation,

[0014] FIG. 5 is a perspective view of the pouch of FIG. 1 in a second configuration,

[0015] FIG. 6 is a schematic view of a folded plastic sheet illustrating the front wall of the pouch of FIG. 1,

[0016] FIG. 7 is a schematic view of a folded plastic sheet illustrating formation of a series of pouches of the type illustrated in FIG. 1, and

[0017] FIGS. 8 to 15 are front views of empty pouches made in accordance with further embodiments of this invention.

DETAILED DESCRIPTION

[0018] Referring to FIGS. 1 and 2, a pouch 20 made in accordance with this invention has a front pouch wall 22 joined to a rear pouch wall 23 (FIG. 5) along opposite side edges 24, 26, along a top edge 30, and along a bottom edge 32. The pouch walls are made of a flexible material, such as plastic, and the pouch is filled with a flowable product, such as a fluid (e.g., yoghurt or water.

[0019] The front pouch wall may be joined to the rear pouch wall at side edges 24, 26 by sealing the walls together at these edges. This forms a sealed band 34 along the side edges. Similarly, the front and rear pouch walls may be joined to each other at one or both of the top and bottom edges by sealing these walls together. As illustrated in FIGS. 1 and 2, the front and rear walls are sealed together at the top edge 30. On the other hand, the front and rear walls are joined at the bottom edge 32 by virtue of the flexible material from which the pouch is constructed being integral at the bottom edge.

[0020] Because the pouch 20 is flexible and filled with a flowable product, the configuration of the pouch differs depending upon which portion of the pouch rests on a supporting surface. As illustrated in FIGS. 1 and 2, the pouch is resting on the pouch rear wall 23 (FIG. 5).

[0021] With the flexible pouch resting on its rear pouch wall 23, the front pouch wall 22 is substantially flat. In this configuration, with specific reference to FIG. 2, the front pouch wall has a maximum width at a first level L1 above the bottom edge 32 and concave opposite sides 24b, 26b between the first level L1 and the bottom edge 32. In consequence, the width of the front pouch wall 22 progressively decreases below the first level L1 down to a second level, L2. In fact, the side edges 24b, 26b form an inwardly directed corner 28 at the second level L2. The flowable product in the pouch causes the pouch to bulge, thus, the true shape of the front pouch wall 22 will only be apparent when the pouch is empty.

[0022] FIG. 3 illustrates, in front view, an empty pouch 20′ such that the front pouch wall 22 is flat. From FIG. 3, it will be apparent that the concave opposite sides 24b, 26b between the first level L1 and the bottom edge 32 of the pouch trace arcs of a circle. The radius, r, of these arcs may be less than 1.5″ (3.8 cm). The distance, x, between the first level L1 and the bottom edge 32 of the pouch 20′ may be about 27% to 30% of the width, W, of the pouch at the first level, L1. Furthermore, a distance, y, measured along said first level, between a corner 38 of the front pouch wall 22 at level L1 and a corner 40 where the side 24b or 26b meets the bottom edge 32, is about, is about 65% to 70% of the distance x. By comparing FIG. 3 with FIG. 2, it will be apparent that with the pouch filled, the radius of the sides 24b, 26b breaks to form the afore-referenced inwardly directed corner 28. This break point is predictably located. Consequently, with the radius, r, the same for both sides 24b, 26b, this pouch configuration facilitates achieving a vertical orientation for the pouch when stood up.

[0023] As is apparent from FIGS. 1 to 3, the pouch has a narrow neck 44 and an enlarged head 46. The neck meets the head at a corner 48 so as to provide a tear point which, as illustrated in FIG. 4, facilitates separation of the head from the neck in order to open the pouch. Optionally or additionally, the pouch may be provided with a notch 50 to facilitate tearing the neck of the pouch at this notch. With reference to FIG. 3, for reasons which will become apparent, the sides 24t, 26t at the head 46 are mirror images of the sides 24b, 26b at the base between level L1 and the bottom edge 32. Thus, the head 46 has convex opposite sides 24t, 26t such that a width of the front pouch wall progressively increases above the neck 44 and defines the same dimensions, x, y, and r, as are defined at the base of the pouch.

[0024] If the filled pouch 20 of FIG. 1 is lifted up and set down on a flat surface bottom edge first, the sides 24b, 26b between the first level L1 and the bottom edge 32 collapse under the weight of the overlying portions of the pouch to provide a stable basal platform for the pouch. FIG. 5 illustrates the pouch in this configuration. Referring to FIG. 5, it will be apparent that as the pouch is set down, the sides 24b, 26b fold at corners 28. Further, the bottom edge flattens. The result is a flat basal platform 52 with a hexagonal perimeter and a self-standing pouch.

[0025] Because each corner 28 is predictably located, being a function of the radius, r (FIG. 3), with the radius r the same for both sides 24b, 26b, this pouch configuration facilitates achieving a vertical orientation for the pouch when stood up.

[0026] Turning to FIG. 6, the pouch may be manufactured from a folded plastic sheet 56 utilising curved heat sealing bars (not shown) which seal the sheet at sides 24, 26 and top 30. The bottom edge 32 naturally results from the fold in the sheet 56. With reference to FIG. 7, sheet material may be conserved by alternately orienting and nesting adjacent pouches 20 that are formed in the sheet 56. It is with this approach to forming the pouches 20 that the sides 24t, 26t of the neck are mirror images of the sides 24b, 26b at the bottom of the pouch. Furthermore, with this approach, where one pouch has a top seal 30 and a bottom edge naturally resulting from the fold in the sheet, the adjacent pouch formed from the sheet 56 will have a bottom seal and a top edge naturally resulting from the fold in the sheet.

[0027] One convenient manner of forming pouches 20 is to use vertical form, fill, and seal technology. With this approach, a sheet is folded around a product supply pipe and free side edges of the folded sheet are sealed together to form a vertical tube. A bottom seal is then formed in the tube and the tube partially filled with flowable product. Heat sealing bars may then press together to displace the flowable product and form successive pouches which may be cut from the tube. This approach to forming pouches is further described in U.S. Pat. No. 6,164,042 to Tobolka, the contents of which are incorporated herein by reference.

[0028] FIGS. 8 through 12 illustrate, in front view, empty pouches 120′, 220′, 320′, 420′, 520′, respectively, having different pouch configurations. Each of pouches 120′, 220′, 320′, 420′, 520′ may also suitably be formed from a folded plastic sheet in a nested fashion.

[0029] With specific reference to FIG. 10, empty pouch 320′ has oblique linear bottom sides 324b, 326b extending between level L1 and the bottom edge 332 of the pouch. Thus, the width of the front pouch wall 22 progressively decreases below the first level (L1 down to the bottom edge of the pouch. With this pouch configuration, when the pouch is full, while the bottom sides 324b, 326b will break to form an inwardly directed corner, the location of this corner will not be predictably located (in contrast to the situation where the bottom sides are configured as arcs of a circle). Because of this, the pouch of FIG. 10 might not stand vertically when set down, bottom edge first.

[0030] With specific reference to FIG. 11, pouch 420′, bottom sides 424b and 426b have a first linear section 427 between the first level L1 and a second level L2a and a second linear section 429 between the second level L2a and the bottom edge 432. In consequence, the front pouch wall 422 is narrower at said second level L2a than at either the first level L1 or the bottom edge 432. The pouch of FIG. 11, when filled, will form a predictably positioned inwardly directed corner (between linear sections 427 and 429). Consequently, this pouch configuration facilitates achieving a vertical orientation for the pouch when stood up.

[0031] The pouch of FIG. 12 differs in that its neck portion 544 is off to one side rather than being centrally located.

[0032] FIG. 13 illustrates, in front view, an empty pouch with yet another pouch configuration. With reference to FIG. 13, pouch 620′ has linear sides 624, 626 above level L1 and radially concave sides 624b, 626b. In consequence, pouch 620′ cannot be formed in a nested fashion as can the pouches of the previously described embodiments.

[0033] FIG. 14 illustrates, in front view, an empty pouch with a further pouch configuration. With reference to FIG. 14, pouch 720′ has concave sides 724b, 726b which flare outwardly proximate the bottom edge 732 of the pouch. In consequence, the width, W, of the front wall 722 of the pouch at level L1 is actually less than the width, W2, of the front wall at the bottom edge 732. As a result of this configuration, when pouch 720′ is full, and set down, bottom edge first, the side walls 724b, 726b collapse leaving projecting tabs at the base of the pouch. If such tabs were considered somewhat unsightly, one of the other pouch configurations could be chosen.

[0034] FIG. 15 illustrates, in front view, an empty pouch 820′ which has angulated, rather than curved, edges. Thus, pouch 820′ has straight edge sections 824, 827, 829, 832, 826, 830 meeting adjacent edge sections at an angle.

[0035] Similar to the designs of a few of the previously referenced pouches, in the pouch 820′ of FIG. 15, the medial portion of the side edge sections 824, 826 between the concave basal portions 824b, 826b and neck 844 are straight. In consequence, when the pouch contains a flowable product and is set down on its base, these medial side edge portions are vertically oriented. This results in the flowable product being displaced vertically upwardly as the pouch is set down, avoiding distortion of the sides of the pouch, which occur in certain of the other designs, such as pouch 220′ of FIG. 9.

[0036] If the pouches illustrated in FIGS. 8 through 15 are made by the process described in conjunction with FIGS. 6 and 7, each pouch will have a sealed band along all but either its top edge or its bottom edge, with the front and back walls of the pouch being integral at the edge which is not sealed. By way of example only, the pouches of these figures have been shown in this way, with the pouches of FIGS. 8 through 14 having sealed bands along all but their bottom edges and the pouch of FIG. 15 having a sealed band along all but its top edge.

[0037] It will be apparent from the foregoing that it is the geometry of the pouch, interacting with the fluid dynamics in the pouch, that results in the flat base when the pouch is set down. There is no requirement for gussets or secondary cross-seals in order to gain the stand-up feature.

[0038] A further advantage of the described pouches is that they may be shipped flat (i.e., resting on their front or back wall as illustrated in FIGS. 1 and 2) to conserve space, without interference from the stand-up feature. Yet further, shipping the pouches flat will not damage the stand up feature, nor stress the .pouch (which could increase the incidence of leaking pouches).

[0039] Other advantages and modifications within the scope of the invention will be apparent to those skilled in the art and, therefore, the invention is defined in the claims.

Claims

1. A flexible pouch containing a flowable product, comprising: a front pouch wall joined to a rear pouch wall along opposite side edges and along a bottom edge; said front pouch wall, when flat, having a first width at a first level above said bottom edge and concave or oblique opposite sides between said first level and said bottom edge such that a width of said front pouch wall progressively decreases below said first level, at least down to a second level, so that, when said pouch containing said flowable product is set down bottom edge first on a flat surface, said sides between said first level and said bottom edge collapse to provide a stable basal platform for said pouch.

2. The pouch of claim 1 wherein a width of said front pouch wall, when flat, at said bottom edge is less than said first width.

3. The pouch of claim 2 wherein said first width is a maximum width of said front pouch wall, when flat.

4. The pouch of claim 1 wherein said front pouch wall is sealed to said rear pouch wall along said opposite side edges.

5. The pouch of claim 1 wherein each of said opposite sides below said first level defines a concave radius.

6. The pouch of claim 5 wherein said radius is less than about 1.5″ (3.8 cm).

7. The pouch of claim 1 wherein, when said front pouch wall is flat, each of said opposite sides defines a first linear section between said first level and said second level and a second linear section between said second level and said bottom edge such that said front pouch wall is narrower at said second level than at either said first level or said bottom edge.

8. The pouch of claim 1 wherein each of said opposite sides is linear such that said front pouch wall, when flat, tapers from said first level to said bottom edge.

9. The pouch of claim 1 wherein, when said front pouch wall is flat, the distance between said bottom and said first level is about 27% to 30% of said first width.

10. The pouch of claim 9 wherein a distance between an edge of said front pouch wall, when flat, at said first level and an edge of said front pouch wall at said bottom, measured along said first level is about 65% to 70% of said distance between said bottom and said first level.

11. The pouch of claim 1 wherein said flowable product is a fluid.

12. The pouch of claim 1 wherein said front pouch wall and said rear pouch wall are configured to define a narrow neck and an enlarged head.

13. The pouch of claim 12 wherein, at each side, said neck meets said head at a corner so as to provide a tear point to facilitate separation of said head from said neck.

14. The pouch of claim 12 wherein, with said front pouch wall flat, said head has a first width at said neck and convex or oblique opposite sides between said neck and a top of said pouch such that a width of said front pouch wall progressively increases above said neck, at least up to a level between said neck and said top.

15. The pouch of claim 14 wherein each of said sides at said head is a mirror image of each of said sides between said first level and said bottom.

16. The pouch of claim 1 wherein said pouch is formed of plastic.

17. A fluid filled flexible plastic pouch comprising: a front pouch wall joined to a rear pouch wall along opposite side edges and along a bottom edge; said front pouch wall, when flat, having a maximum width at a level above said bottom edge and concave or oblique opposed side edges between said level and said bottom edge.