Abstract:
The disclosure relates to a multilayer film bag ( 1 ) for storing food products, in particular beverage concentrates, with a bag wall ( 7 ) including at least one external wall ( 10 ), one barrier layer ( 9 ), for example for oxygen and/or light, and one internal wall ( 8 ). The multilayer film bag includes a predetermined breaking point ( 2 ) in the film bag wall which tears open under pressure, for example at pressures above 100 kPa, 150 kPa, 200 kPa, 400 kPa or 500 kPa without any parts of the film bag tearing off.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to a film bag for storing products, in particular food products, such as beverage concentrates which are mixed with water (still or enriched with CO2) as soft drink. The invention furthermore also relates to a method of draining a film bag. 
       BACKGROUND 
       [0002]    Multilayer film bags are known, for example, from EP0473517, where a tear-off seam is worked into the film bag under the action of laser, so that it can be more easily opened by a user. However, opening the film bags described in EP0473517 by machines is cumbersome. 
         [0003]    In U.S. Pat. No. 642,068S, a foil impermeable to oxygen is welded onto a container by means of thermal processes after the product has been placed into it. However, the container itself does not include any oxygen barrier. The manufacture, filling and sealing of the container requires several process steps and is therefore complicated and expensive. The viscosity of the products is restricted to liquid and free-flowing products as these can be easily flushed or pressed out of the container. For this, complex apparatuses are required which then mix the product, for example, with water into the beverage. An increased germ contamination can also occur here as the product flows over the unsterile edge of the container. 
         [0004]    It is thus an object of the present disclosure to provide a film bag, a method, and a device, so that it becomes possible to drain a shapeless film bag nearly without leaving any residues, and wherein the film bag additionally includes barriers for light and/or oxygen and is microbiologically safe to handle. 
       SUMMARY 
       [0005]    This is achieved according to some aspects by a multilayer film bag according to claim  1 , a method according to claim  11 , and a device according to claim  16 . Advantageous embodiments and further developments are the subject matter of the sub-claims. 
         [0006]    The multilayer film bag disclosed herein with a bag wall including at least one external wall, one barrier layer, for example for oxygen and/or light, and one internal wall includes a weakening in the film bag wall which tears open at a predetermined breaking point in a controlled manner under the action of pressure, for example at pressures above 100 kPa, 150 kPa, 200 kPa, 400 kPa or 500 kPa, i.e. in particular e.g. without any parts of the film bag getting detached in the process. 
         [0007]    This has the advantage that the film bag can be easily and safely emptied mechanically nearly without leaving any residues independent of its shape and that no detached parts of the film bag affect and optionally microbiologically contaminate subsequent method and product treatment steps. 
         [0008]    The weakening as predetermined breaking point, which is advantageously centrically attached on an external wall side of the film bag and is produced, for example, under the action of light, can have an extension which is advantageously smaller than one half, one third, or one fourth of the extension of the external wall side on which the predetermined breaking point is located. A position of the predetermined breaking point centered on the external wall of the film bag can facilitate the mechanical draining of the film bag under the action of pressure as it can thus be better ensured, for example, that the weakening or the predetermined breaking point, respectively, is located above the outlet opening of the draining chamber independent of rotations of the film bag in one plane. However, non-centered positions of the predetermined breaking point on the external wall side of the film bag are also conceivable. 
         [0009]    Advantageously, the film bag can have a rectangular shape and comprise at least one weld seam for closing the film bag after it has been filled, the weld seam/weld seams being resistant to pressures above the aforementioned pressure ranges leading to an opening of the predetermined breaking point. 
         [0010]    Moreover, the predetermined breaking point can include a cover, for example a protective foil, against contamination and soiling which can be fixed by an adhesive, and a cover tongue by which the cover can be removed manually or mechanically before draining. 
         [0011]    It is furthermore advantageous for the depth of the predetermined breaking point in the external wall of the film bag not to reach deeper than to the barrier layer. This advantageously ensures that the product stored in the film bag is not affected by light or oxygen which could penetrate into the region of the predetermined breaking point before opening. 
         [0012]    The film bag can preferably have height dimensions that are smaller than the length and width dimensions. 
         [0013]    Equally, the film bag can be provided with a position detection mark. This can facilitate the verification of the correct position and orientation of the film bag in a draining device. 
         [0014]    Under the action of pressure, the predetermined breaking point can advantageously bulge outwards and form an outward shape before it is torn open/opened. The film bag can then be drained more easily and nearly completely after it has been torn open under relieved pressure without leaving any residues. 
         [0015]    Moreover, it is advantageously possible for the bag wall to bulge with the predetermined breaking point during draining such that the predetermined breaking point closes after draining in a drip-tight manner. 
         [0016]    Film bags in which liquids having a viscosity of &gt;100 mPa s are stored can thus be drained largely without leaving any residues in accordance with the invention. 
         [0017]    In a further advantageous embodiment of the invention, it is conceivable that a small quantity of gas, for example an air bubble, is located in the flat-lying container at the side wall located above and opposite the predetermined breaking point, and that it flushes the outlet opening of the predetermined breaking point free from any product when the film bag is being drained. 
         [0018]    According to the disclosure, draining the film bag can be effected by means of a draining device as follows. 
         [0019]    In the process, the film bag is placed into a draining chamber whose geometrical dimensions can preferably be adapted, as concerns its draining chamber width and draining chamber length, to the film bag width and film bag height, and pressure is exerted onto the film bag by means of a pressing device, by the pressing device lowering down, for example, onto the film bag, so that a bulging is formed which, when the film bag wall is overexpanded on the side of the predetermined breaking point, opens the predetermined breaking point, for example in its center, and the film bag is drained nearly without leaving any residues. 
         [0020]    Additionally, when pressure is applied, it can be distributed uniformly across the surface of the film bag by means of a compressible cushion at the pressing device. 
         [0021]    When the pressing device is lowered, the cushion of the pressing device can advantageously expand into the bulge of the film bag wall because no resistance is formed in the region of the outlet opening of the draining chamber, and it can press out the product stored in the film bag nearly completely. 
         [0022]    It is also possible to flush the product residues out of the film bag when the film bag is being drained by means of an air bubble in the film bag which is located at the uppermost point of the bag height in the draining position. 
         [0023]    It is furthermore possible to drain the film bag into/above a product chamber and to flush the product chamber after the film bag has been drained, for example with mixing water (still or blended with CO2). 
         [0024]    The attached figures show by way of example 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]      FIG. 1   a  is a three-dimensional or isometric view of an exemplary design of a film bag. 
           [0026]      FIG. 1   b  is a plan view onto the film bag of  FIG. 1   a.    
           [0027]      FIG. 1   c  is a cross-section through the film bag wall. 
           [0028]      FIG. 1   d  is a plan view onto the predetermined breaking-points in different shapes. 
           [0029]      FIG. 2  is a three-dimensional or isometric view of a cover. 
           [0030]      FIG. 3   a  is a side view as a section of a draining device with an inserted film bag. 
           [0031]      FIG. 3   b  is a cross-section of the snapshot of a step in the process of draining the film bag. 
           [0032]      FIG. 3   c  is a cross-section of the snapshot of the flushing step. 
           [0033]      FIG. 4  is a three-dimensional or isometric view of a drained film bag. 
           [0034]      FIG. 5  is a side view as a section in an exploded view of a draining device. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]      FIG. 1   a  shows a three-dimensional view of an exemplary multilayer film bag  1  with a predetermined breaking point  2  produced under the action of light. Here, the height  3   a  of the film bag  1  is smaller than the length  3   b  and the width  3   c.    
         [0036]      FIG. 1   b  by way of example shows a view of the film bag side of the film bag  1  of  FIG. 1   a  on which the predetermined breaking point  2  is located. By way of example, the predetermined breaking point  2  is located at the bottom side  6  of the film bag  1 . 
         [0037]    In this example, the length  3   b  and the width  3   c  of the container have the same edge lengths, however, the geometric shape of the film bag  1  can also be designed in another shape, e.g. as rectangle, polygon or circular shape. The positioning of the weakening of the predetermined breaking point  2  on the bottom side  6  of the container  1  can advantageously be located in the diagonal position  4  and/or advantageously in the center  5  of the film bag  1 . However, other positions of the weakening of the predetermined breaking point  2  which are neither centered nor located on a diagonal line are also conceivable. To be able to ensure that the operator/a machine has placed the container  1  the right way round in the draining chamber  24 , independent of rotations with respect to the plane of insertion, the film bag  1  can be provided with a position detection mark  2   a  as marking. This position detection mark  2   a  can be designed, for example, as notch in the bag wall, as a hole, as a painting, as printing, as a sticker, etc. 
         [0038]      FIG. 1   c  shows a view as a section through a multilayer film bag wall  7 . The internal wall layer  8  of the film bag wall can advantageously consist of thermoplastics, e.g. PE, PP, PET, PA, or else of natural rubber or rubber, and be weldable. Preferably, the extensibility at a low compressive force is &gt;1 Newton, however &lt;100 Newton, preferably 20 Newton. 
         [0039]    A central barrier layer  9  functions as protection of the product  33  for shielding off luminous radiation and/or gas diffusion, for example oxygen diffusion, and can consist, for example, of aluminum. 
         [0040]    Like the internal wall layer  8 , the external wall layer  10  of the film bag wall  7  can also advantageously consist of thermoplastics, e.g. PE, PP, PET, PA, or else of natural rubber or rubber, and have an extensibility at a low compressive force of &gt;1 Newton, however &lt;100 Newton, preferably 20 Newton. 
         [0041]    In an exemplary embodiment, the film bag  1  can have an internal wall layer  8  of 40 μm PE, a barrier layer  9  of 7 μm aluminum, and an external wall layer  10  of 12 μm PET. All these thickness specifications can deviate by 10% or 20% or even more upwards or downwards, i.e. the PE layer thickness can be e.g. 40 μm±10 or 20%, but also larger. 
         [0042]    The weakening produced as predetermined breaking point  2  under the action of light can have a depth  11  advantageously down to the surface of the barrier layer  9  as thereby the pressure application for opening the film bag wall  7  is lowest while the function of the barrier layer  9  is not or only insignificantly affected. The predetermined breaking point  2 , however, can also be produced by other methods, for example by scratching. 
         [0043]    When the predetermined breaking point  2  is produced, the integrity at least of the lowermost barrier layer  9  can be ensured by means of an Nd:YAG or CO2 laser light source. 
         [0044]      FIG. 1   d  shows a view as a plan view of the predetermined breaking point  2  produced by the action of light in different exemplary shapes  13   a . For the selection of the different shapes  13   a , it is advantageous for the greatest weakening to start from the center  14  of the predetermined breaking point  2 , so that a uniform bulge  30  is produced and thus a uniform outward shape  13  can be achieved when the film bag  1  is opened starting from the predetermined breaking point  2 , and the jet angle of the product  41  can be influenced. However, predetermined breaking points whose maximum weakening does not start from the center  14  of the predetermined breaking point  2  and other forms can also be used. However, the star shape  13  is a preferred predetermined breaking point shape. 
         [0045]      FIG. 2  shows a three-dimensional view of an exemplary cover  15  by which a predetermined breaking point  2  of a film bag  1  can be covered. The size of the cover  15  of the predetermined breaking point  2  can be governed, for example, by the cross-sectional area of the draining chamber  24 , so that during transport and handling by the operator/a machine, the points in the draining chamber that come into contact with the product remain hygienic and clean. Here, germ contamination of the product  33  by microorganisms during the draining of the film bag  1  can be prevented. The cover  15  on the film bag  1  can be fixed, for example, by means of an adhesive and additionally comprise, for facilitating handling by the operator/a machine for removing the cover from the bag wall, a cover tongue  16  which is not fixed to the film bag wall by means of an adhesive but can be lifted off, so that by gripping the cover tongue  16  and pulling it, the cover  15  can be detached. 
         [0046]      FIG. 3   a  shows a side view as a section of an exemplary draining device  17  with a film bag  1  inserted in the draining chamber  24  and the pressing device  18  resting on it/against it. The exemplary positioning of the film bag  1  causes an air bubble  34  to be located at the film bag wall opposite the predetermined breaking point. The draining chamber  24  can have at least one outlet opening  36  which can be joined by a product chamber  32 . The pressing device  18  can additionally comprise a compressible cushion  21 . Equally, the draining chamber  24  can have a flush connection  39  via which the product chamber  32  or parts of the draining chamber  24  and parts of the film bag  1  can be flushed, for example, with mixing water (still or blended with CO2). 
         [0047]      FIG. 3   b  shows a side view as a section of an exemplary draining device  17  in the snapshot of a draining process step of the inserted film bag  1 . 
         [0048]    By the pressing action of the pressing device  18 , the container wall  7  can expand into the outlet opening  36  of the draining chamber  24  and a bulge  30  can be formed in the process which leads to the elongation at break of the predetermined breaking point  2  being exceeded and opens the film bag  1 , so that the product  33  can flow out of the film bag. Advantageously, the pressing action of the pressing device can be slowly increased, for example from 0−200 kPa, or from 0-500 kPa or more in 5-30 s, or within 1-100 s, e.g. to be able to achieve a better splashing behavior, for example by restricting the product jet angle  41  to less than 180° of the product exiting from the film bag  1 . 
         [0049]    The draining device  17  can be designed such that the pressing device  18  can be positioned in a controlled manner. In the process, the position of the pressing device  18  is adjusted by suited means, where this positioning can be effected independent of whether a film bag  1  is present or not. The pressing device  18  is moved, for example, at a preset and continuously variable speed, this being done independent of whether a film bag  1  is present or not. The preset speed can be, for example 0.1, 0.5, 1.0, 2.0, 5.0, 10, 20 or 40 mm per minute or more. The preset speed can also be below one of these values. 
         [0050]    Pressure variations of 0.0−200 kPa or 0.0−500 kPa can be achieved here, for example, in 5-30 s or within 1-100 s. This can help to achieve a controlled pressure build-up in the film bag  1 , and thus a sudden or uncontrolled lowering of the pressing device  18 , accompanied by an undesired sudden opening of the container, can be prevented. For this, the pressing device  18  is moved, for example, hydraulically or electromotively, where by a defined flow rate of hydraulic pressurizing/propellant agent into a hydraulic cylinder or motor provided for moving the pressing device  18 , or by a defined rate of motion of a motor (for example an electric motor, such as a stepper or asynchronous motor), the speed of motion of the pressing device  18  is defined. The control or pressurization of the pressing device  18  can also be effected, for example, by means of a threaded spindle which is driven, as explained above, by an electric motor or hydraulically. 
         [0051]    A minimum speed of, for example, 0.05, 0.10, 1.00 or 20 mm per minute is required to achieve a controlled draining of the film bag, a speed below a maximum speed of, for example, 100, 200 or 500 mm per minute ensures a slow and controlled opening of the film bag  1 . 
         [0052]    The pressing device  18  can have a compressible cushion  22  which can, when the pressing device is lowered/presses, expand into the bulge  23  formed in the process, as in the region of the outlet opening  36  of the draining chamber  32 , no resistance builds up, and it can in this manner press out product residues in the film bag  1 , in particular in the bulge  31  of the predetermined breaking point  2  of the already largely drained film bag. 
         [0053]      FIG. 3   c  shows a side view as a section of an exemplary draining device  17  in the snapshot of a flushing process with mixing water/mixing agent. Via the flush water inlet  39 , the bulge  30  of the film bag  1  and the outward shape of the predetermined breaking point  2  of the film bag, parts of the draining chamber  24  and the product chamber  32  are flushed, for example with water  44  blended with CO2, so that nearly no product residues are left. So, the product and the flush-out agent can be found e.g. as mixed drink in the mixing tank  43 . 
         [0054]      FIG. 4  shows a three-dimensional view of a nearly completely drained film bag  1  which by way of example has a uniform outward shape  31  around the center  14  of the predetermined breaking point  2  which was produced by stretching along during the formation of the bulge  30  of the film bag wall  7  by the pressing operation/pressurization. 
         [0055]      FIG. 5  shows a side view as a section of an exemplary device  17  for draining the film bag  1 . The draining device  17  preferably consists of a draining chamber  24  of which the geometrical dimensions can be adapted to the size of the container  1  as to its length  3   b  and width  3   c , so that a container  1  filled with product can be inserted into the draining chamber  24  nearly without any gaps. Here, the surrounding distance  26  of the pressing device  18  to the internal wall  25  can be between 0.01 mm and 20 mm, but is preferably 1±0.5 mm. One can thereby avoid that the container is pressed into and/or gets clamped in the distance  26  between the draining chamber  24  and the pressing device  18  during pressing. The shape of the draining chamber  24  can be, for example, rectangular or square, where the draining chamber  24  can, for example, form a pan whose side wall design or internal wall  25 , respectively, can be higher than the flatly inserted container  1  filled with product. 
         [0056]    The draining device  17  can comprise a pressing device  18 , for example with a pressure plate or plunger  18   a , whose geometrical dimensions can be somewhat smaller than the surrounding internal wall  25  of the draining chamber  24 , but which can preferably be inserted into the draining chamber  24  with an accurate fit. 
         [0057]    Pressure can be exerted onto the container  1  inserted in the draining chamber  24  via the pressing device  18 . Here, the container  1  can bulge into the product outlet opening  36  of the draining chamber  32  until the predetermined breaking point  2  opens and drains the container. The drive of the pressing device  18  is designed, for example, hydraulically or electronically, as described above with respect to  FIG. 3   b.    
         [0058]    The pressing device  18  can include a compressible cushion  21  at its bottom side, for example an air cushion or an elastomer, via which pressure can be exerted onto the film bag  1 . In the process, the compressible cushion  21  can image the container&#39;s contour, and thus a uniform pressure distribution onto the container  1  and onto possible weld seams and pleats of the container can be achieved. 
         [0059]    The draining chamber  24  can include an opening  36  for the product outlet which is located, for example, centrically in the bottom  27  of the draining chamber. However, several openings are also possible. 
         [0060]    When pressure is exerted onto the inserted container  1  filled with product with a pressing device  18  with a compressible cushion  21 , the cushion can expand into the product outlet opening  36  of the draining chamber  24  and thus better drain the container. 
         [0061]    A product chamber  32  whose volume  35  can, for example, receive the complete product  33  that can be located in the film bag  1 , can follow the opening  36 . The product chamber  32  can additionally comprise a product chamber outlet opening  38 , for example in the vertical extension of the product chamber  32  or, for example downwards in the direction of gravity, where the outlet opening  38  can have a smaller cross-section than the product chamber  32 ; for example, the outlet opening  38  can have a cross-section which is by 1% to 90% smaller than the cross-section of the product chamber  32  to be able to effect a product back-up 42. For example, a width of the product chamber of e.g. 30 mm diameter and an outlet opening of e.g. 6 mm are preferred. The design of the product chamber outlet opening  38  can extend, for example, conically in the direction of gravity. 
         [0062]    The opening  35  of the product chamber can moreover comprise an inlet  40  to a flush connection  39 , for example directly underneath the draining chamber  24 . Preferably, the inlet  40  can be designed, for example, tangentially. After the container  1  has been drained, mixing water  44 , for example blended with CO2, can be supplied to the product chamber  32  and/or the region directly underneath the draining chamber product outlet opening  36  via the flush connection  39  and the inlet  40 , and the product chamber  32  can be flushed in this way. 
         [0063]    Moreover, a mixing tank  43  for receiving the product  33  and/or mixing/flushing water  44  can be located underneath the outlet opening  38 . 
         [0000]    The reference numerals used herein are as follows:
     1  Film bag/multilayer film bag     2  Predetermined breaking point     2   a  Position detection of the film bag     3   a  Height of the film bag     3   b  Length of the film bag     3   c  Width of the film bag     4  Diagonal positioning     5  Center of the film bag     6  Bottom side of the film bag     7  Wall of the film bag/bag wall     8  Inner wall layer of the bag wall     9  Barrier layer of the bag wall     10  External wall layer of the bag wall     11  Depth of the predetermined breaking point     12  Width of the predetermined breaking point     13  Star-shaped predetermined breaking point     13   a  Different predetermined breaking point shapes     14  Center of the predetermined breaking point     15  Cover of the predetermined breaking point     16  Cover tongue     17  Draining device for a film bag     18  Pressing device for draining the film bag     18   a  Plunger/pressure plate of the pressing device     19  Dimension of the pressing device     20  Outer edge of the pressing device     21  Cushion of the pressing device     22  Compression of the cushion     23  Bulge of the compressed cushion     24  Draining chamber     25  Internal wall of the draining chamber     26  Distance between the draining chamber wall and the pressing device     27  Bottom of the draining chamber     28  Sealing of the container on the bottom of the draining chamber     29  Empty film bag     30  Bulge of the empty or largely empty film bag and/or bulge of the film bag before the predetermined breaking point is opened     31  Outward shape of the predetermined breaking point of the empty or largely empty film bag     32  Product chamber of draining device     33  Product in the film bag     34  Air bubble in the film bag     35  Volume of the product chamber     36  Outlet opening of the draining chamber     38  Outlet opening of the product chamber     39  Flush connection of the product chamber     40  Tangential inlet from the flush connection     41  Jet angle of product during draining of the film bag     42  Product back-up in the product chamber     43  Mixing tank