It is frequently desirable to provide a mechanism for venting air or other gas from a packaging container (whether a bag or otherwise) during filling, or during transportation so that any trapped air or other gasses within the package can be vented in order to compact the contents. This is particularly so with bags to contain a particulate (e. g. powder, granulated, flaked, or the like) content especially where the bag or an inner plastics pouch thereof is substantially gas impervious.

BACKGROUND Typically containers filled with a particulate (solids) material (e. g. powder, granules, flakes, etc) contain a considerable amount of air or other gasses trapped during the filling operation. This results in the container having a greater than desired volume for the particulate content. If, for example, a bag, this is undesirable in transportation as it creates problems in the stacking of the filled bags. With large quantities of air are trapped in a bag, the pressure of a number of bags in a stack (should the bag still be stackable) may cause the entrapped air to balloon out and even rupture the bag.

The problem with filling with a particulate material is not confined to bags.

Frequently containers whether in the form of boxes, flasks, sachets, etc. are reliant in some circumstances (e. g. during accumulation or stacking) on the contents to retain the shape and/or physical integrity of the filled container. Where very little gas (e. g. air) is entrapped in a sealed container solid materials of the kinds aforementioned readily assume a load bearing capability without placing undue stresses on the integrity of the surround of such contents provided by the container.

Reference herein therefore to"containers"or"container"includes all such forms of container (and not just a bag, pouch, sachet or otherwise) where there is a desirability of allowing a solids content in use to assume a structural function (such as in stacking)

or at least to confine the volume of the filled container (whether under stacking or other loads or not).

Many approaches have been adopted in the past to allow for venting but which otherwise leaves products more or less contained in the container. Examples include bag within bag systems where the inner bag is a plastics pouch. The provision in the longitudinal seams of such plastic pouches of perforations can provide a tortuous path from the interior of what will be the final pouch to that which is the exterior of the pouch but still confined within the less gas impermeable outer bag. See for example, US Patents 3302859,4470153, 4550441 and 6170985.

Other tortuous venting arrangements have relied upon the heat seal between plies of a pouch (whether as a stand alone bag or as content in a multiple bag assembly). In this respect see New Zealand Patent Specification No. 286115 and WO 01/12425.

Still other approaches include the provision of applied filter or interposed membranes. Some of these are good only for smaller volume bags or containers. See for example US Patents 6214392,6274181 and 6355078.

The full content of the aforementioned patent specifications is each herein disclosed by way of reference.

Several of the procedures referred to require a significant modification of a bag forming line and particularly one where there is to be a customer filable plastics pouch provided inside a less gas impermeable outer. Some of the examples given require the tube forming for the provision of the pouch on the machine itself. This can give difficulty. Production speed may need to be reduced.

What is desired is a low cost procedure readily associable with production lines which will provide with low cost consumables and easily positioned ancillary equipment venting, flexibility as to where the venting is provided, a prevention of contamination of the contents by ambient conditions, better prevention of a return of any gas back into the container and a prevention of any substantial stop leakage from the container via the venting feature.

For example, with some of the aforementioned prior art procedures, apertures in a seam of a bag need to be large enough and/or present in such numbers to allow the escape of a sufficient volume of air yet still need to be small enough in size and SUBSTITUTE SHEET (RULE 26)

numbers if leakage of powder or other particulates are to be prevented out of such a venting feature. In addition, if the apertures are too large, the product will be suspected as allowing the ingress of insects thereby preventing the product from being used for food purposes or for pharmaceutical purposes.

By way of an example a material frequently encountered that does create difficulties and requires care in its handling are dairy powders such as milk powder or milk fraction powders. There have been many attempts to provide vented containers (including bags) for such powders.

The present invention is also directed to such provision but is not confined to such content options.

OBJECT It is an object of this invention to provide a vented container (such as a bag), a method of providing such a vent, labels for use in defining such a vent, and related assemblies and uses which will allow a useful option to product packagers.

It is also an object of the present invention to provide a bag of a substantially gas impermeable material or air impermeable material capable of being sealed yet being provided with a one way venting feature which will meet some of the aforementioned needs and/or at least provide the public with a useful choice, such a bag, in some forms of the present invention, being produceable with little in the way of departure from manufacturing procedures hitherto used other than in respect of the provision of the venting feature.

In still a further aspect it is an object of the invention to provide a container for a particulate material or including a particulate material having a one way air or gas venting feature that differs from any of those previously mentioned.

STATEMENT OF INVENTION In one aspect of the present invention consists in a container suitable for a particulate material or containing a particulate material, wherein, as a venting feature to have a venting mode and a non-venting mode so as to favour one way gas passage outwardly of the container, a region or panel ("panel") SUBSTITUTE SHEET (RULE 26)

of the container includes at least one aperture ["aperture (s) "] overlaid with a label having at least one aperture ["aperture (s)"], the aperture (s) of the panel and the aperture (s) of the label not being in register, and wherein the label is affixed to the panel so as to be able, in use, in a venting mode, under the influence of a gas from within the container to separate or billow outwardly sufficiently to allow a venting of at least some of that gas through the aperture (s) of the panel and in turn out of the aperture (s) of the label, and, in a non-venting mode, to assume a substantially unseparated or non- billowing form to restrict ingress of gas into the container from outside of the label and restrict or at least reduce passage through the venting feature of any particulate material from the container.

As used herein"label"means any discrete patch or like member capable of being affixed by self adhesive or any other means to the material of the panel or region of the container or bag.

The term applies irrespective of whether the label is transparent, translucent or opaque. The term applies irrespective of whether any writing or other indicia is present thereof.

Preferably the label is peripherally adhered to the panel.

Preferably the label has been adhered to the panel reliant on a pressure adhesive carried by the label.

Preferably there are a plurality of apertures in (i) the panel, (ii) the label or (iii) both the panel and label, each in the form of a slit or cut without any cut out.

Preferably each slit or cut is of the form of a simple slit, cross forming slits or a starburst forming slits.

Preferably the label is elongate so as to better distance its apertures (e. g.; slits in cross form) (towards each end thereof) from a centralised aggregation of preferably non cutout slits of any form of the underlying panel.

Preferably the container is of a heat salable plastics material or includes a heat salable plastics material.

Preferably said container is in the form of a bag.

SUBSTITUTE SHEET (RULE 26)

Preferably said bag is an inner bag in a bag assembly that includes both an inner bag and an outer bag.

Preferably the outer bag is of a material that is less gas impermeable (e. g.; kraft paper) than the material from which the inner bag has been formed (e. g.; polyethylene).

Preferably the container has been formed from a blown tube of one or more layers of a plastics material.

Preferably the aperture (s) have been made by cutting through the tube either (a) through the single ply of the panel only or (b) through both plies of the tube when in a lie flat condition, the aperture (s) of the panel being overlaid with the label whilst the other aperture (s) being by overlaying with a self adhesive patch (e. g.; a self adhesive tape) or being overlaid another said label.

Preferably said label is peripherally self adhesive and has internally of the self adhesive peripheral zone at least one aperture.

Preferably said label is adapted to be self adhesively applied to a panel of a container and to peripherally self adhere thereto (i. e.; so as to require gas passage through the aperture (s) of the label), the label having internally of the self adhesive peripheral zone one or more apertures each in the form of a slit or cut that does not involve a cut out.

Preferably the label is formed from a plastics material.

Preferably said label includes a registration marking so as to enable machine registration of the label with any complementary registration mark of the region, panel or zone with which the label is to be associated.

In another aspect the invention is a method of forming a container suitable for a particulate material or containing a particulate material, the container being of a kind wherein, as a venting feature to have a venting mode and a non-venting mode so as to favour one way gas passage outwardly of the container, a region or panel ("panel") <BR> <BR> of the container includes at least one aperture ["aperture (s) "] overlaid with a label<BR> having at least one aperture ["aperture (s) "], the aperture (s) of the panel and the aperture (s) of the label not being in register, and wherein the label is affixed to the panel so as to be able, in use,

in a venting mode, under the influence of a gas from within the container to separate or billow outwardly sufficiently to allow a venting of at least some of that gas through the aperture (s) of the panel and in turn out of the aperture (s) of the label, and, in a non-venting mode, to assume a substantially unseparated or non- billowing form to restrict ingress of gas into the container from outside of the label and restrict or at least reduce passage through the venting feature of any particulate material from the container, said method comprising or including in conjunction with the conversion of the tube to a series of bags, providing in the tube for each bag or in each bag one or more apertures and overlaying each region having the aperture or apertures with said label thereby to provide the venting feature.

In yet another aspect the invention is a method of making a bag assembly of a kind having a lie flat outer bag about a lie flat inner bag, the inner bag having a venting feature, said method comprising or including feeding as a web the tube from which the inner bag is to be formed to a tube slitting or cutting device to provide a plurality of apertures in the tube at zones that will equate to the venting feature zone of a panel of the to be formed lie flat inner bag, applying a label with a label applicator over each such zone as the tube as a web progresses thereby to provide the labelled web, feeding both the labelled web and at least one web to provide the outer bag to bag forming apparatus thereby to form the discrete inner bags and the discrete outer bags, the method being characterised further in that the venting feature results from the label and its underlying zone each providing at least one aperture to allow gas passage from the inside of the inner bag via the at least one aperture of the zone and the out of register at least one aperture of the label to the outside of the inner bag.

Preferably the tube slitting device provides for each to be formed inner bag two zones that will require patching with a said label or other patch and the step of applying a label involves, in one instance, for each to be formed bag the application of a said SUBSTITUTE SHEET (RULE 26)

label to one zone and, in the other instance, the application of a said label or a said patch to the other zone.

Preferably the outer bag is at least in part formed from paper.

Preferably the inner bag is formed from one or more layers of a thermoplastics material.

Preferably the method is performed substantially as herein described with reference to any one or more of the accompanying drawings.

The invention is also a bag or bag assembly formed by a method of the present invention.

In another aspect the invention is a lie flat bag assembly of an inner bag and an outer bag each having a closed factory end and an open customer end, the inner bag being characterised in that it is of a substantially gas impervious material but includes as a venting feature a label patching over a zone of the inner bag, the zone of the inner bag including at least one venting aperture and the label itself including at least one venting aperture, the aperture or apertures respectively of the zone and the label not being in register.

In another aspect the present invention consists in a container suitable for a particulate material, for a particulate material or containing a particulate material, said container having a venting feature that allows preferentially the expression of air or gas outwardly from the container as opposed to inwardly and which does not allow any substantial expression outwardly therethrough of the intended or actual particulate content, the vent feature being characterised in that it involves one or more aperture in the wall of the container which is overlaid by a label which itself has one or more apertures which do not coincide with the position of the container apertures.

Preferably said container is a bag.

Preferably the label has a plurality of apertures and the wall has a plurality of apertures and at least one set of apertures are slits without a cutout, such slits being of any form (e. g.; simply slit form, crossed slit form or starburst slit form).

One set of apertures may be from 1 to 10mm in diameter, if formed as circular apertures, and more preferably have a diameter of about 4mm. Alternatively that one set of apertures is also provided as slits (e. g.; preferably of cross form), up to 10mm SUBSTITUTE SHEET (RULE 26)

long. Preferably both sets are of a non cutout (i. e.; slits) form to minimise product loss or contamination.

The actual size and number of the apertures both in the bag, and the label will depend upon the particle size of the material to be contained with the bag, and the speed of air release required.

In another aspect the invention provides a method of producing a vented bag by providing one or more selected apertures in the bag at a selected position, and covering the selected position with a label, wherein the label has one or more label apertures which do not coincide with the position of the bag apertures, so that in use air pressure within the bag will allow air to escape through the bag apertures into the space between the bag and the label, and escape through the label apertures, thus minimising the risk of any air returning in the reverse direction.

In another aspect the invention provides a bag for a particulate material, which bag is provided with an air release mechanism, the air release mechanism being provided by an air release label applied to a portion of the bag.

More preferably the bag is formed to provide a heat salable plastics pouch.

Preferably the plastic pouch is formed from a blown tube (without side seams) which can be cut to length. However, the invention is also applicable to bags folded and seamed from a single sheet of plastics material.

More preferably the label is applied to the bag adjacent to an edge thereof, and preferably adjacent the top of the bag but situated below any resulting heat seal so that any air entrapped within the bag during filling will be able to be vented near the top of the bag before the bag is stacked on a pallet or the like.

Preferably the label is applied by a high-speed label applicator.

More preferably the label is a plastics label and is attached to the bag by means of a suitable adhesive, more preferably a pressure sensitive adhesive.

The apertures can be provided in the bag or its tubular precursor in an inflated condition just before it enters a nip roller. The label can be applied to the bag as it passes over or around a roller.

Alternatively the apertures could be provided in both faces of the bag or, more preferably, its tubular precursor whilst flat. In such a case it would be preferable to SUBSTITUTE SHEET (RULE 26)

apply either two labels or one label and one patch of an impermeable layer, for example a self adhesive tape (e. g.; SELLOTAPETM), or a non-apertured plastics label which would then cover over the apertures on the other side of the bag.

DRAWINGS Some preferred forms of the present invention will now be described with reference to the accompanying drawings in which ; Figure 1 is a schematic view of a bag having one form of an air release label, Figure 2 is a close up view of one form of an air release label for use in the production of bags, Figure 3A is a view of a preferred air release label in accordance with the present invention, the label being elongate in form and provided with a peripheral zone (shaded) of self adhesive, a visible registration mark and a set of two groupings of slits each in the form of crossed slits to act as the vents of the label itself and Figure 3B shows the corresponding preferred zone of the bag with preferably two slits of simple form to associate with a patch of Figure 3A, the zone likewise having a registration mark or showing the juxtaposition of the slots to the label registration mark, Figure 4 is a schematic view of a production line in which the bags are formed from a continuous blown tube and formed into pouches of the desired size, and the bags are provided with apertures and vented labels during production of the bag and prior to the reinforcing of the bag with an outer layer of Kraft paper or the like, Figure 5 shows how a kraft paper wrap to provide a seamed bag about individual bags derived from the tubular web can be provided, in the lie flat form the venting feature being disposed so as, even in a stack situation being able to operate to release gas under stack pressure, and Figures 6A and 6B show two label designs of Trial 4.

In the preferred form of the present invention descriptions will be made by reference to the accompanying drawings.

Figure 1 shows a plastic laminate pouch 10 with air release label 11 and an outer Kraft paperbag 9.

Figure 2 shows out of register slits 12 of a label and underlying pouch slits 13.

SUBSTITUTE SHEET (RULE 26)

A preferred form of label is that shown in Figure 3A. This label (preferably a cast polyethylene label of about 80 g/m2) can be of the form shown in any suitable material (eg; PE, PA, PVC, PET and (preferred) LDPE) with an FDA approved pressure sensitive adhesive periphery bounding the inflatable zone to billow outwardly under venting pressures. As shown there are two sets of three crossed slits (eg; pf abpit 4.5 mm length) inwardly of the peripheral adhesive zone.

A preferred adhesive is a water or non water based poly acrylic adhesive system.

In other forms, less preferred, a hot melt adhesive or another pressure sensitive adhesive system can be utilised.

As can be seen by comparing Figures 3A and 3B the openings provided under venting pressure by the apertures (eg; slits 14 of about 4 mm length) in the region, panel or zone near where registration mark 16 is to sit are distanced from those cross slits 15 shown in Figure 3A thus still providing for adequate venting of gases outwardly from the bag yet providing a self seal region which discourages ingress of ambient air and moreover maintains the integrity of the pack against contamination and/or product loss.

The feature disclosed as applicable to containers of any form particularly where they have a flexible wall or periphery. Such flexibility in the wall or periphery however is not essential as venting labels in accordance with the present invention can even be applied to rigid containers. The invention lends itself to packs of all kinds ranging from bulk bag packs through to multi bag assemblies, single bag forms, etc.

By way of an example, see Figure 4 where there is shown as 1 a feed of a blown tube towards a bag forming machine 3 via a slit cutter device 2 and high speed label and/or patch applicators 3. There is preferably disposed at 4 a visual inspection zone to ensure the label positioning just prior to the entry of the web with its labels/patches into the machine via nip rollers. The machine 5 can be of any appropriate kind but is preferably one that wraps an outer bag forming web (e. g.; of kraft paper) 6 about the labelled web 7 from which the inner pouches are to be formed. As can be seen in Figure 4 preferably rolls 8 provide the feed of, for example, kraft paper 8A through the machine as shown.

A preferred bag forming machine 5 is that of Wind Moller & Holscher. Persons skilled in the art will appreciate the machine types utilised.

SUBSTITUTE SHEET (RULE 26)

As far as the label and/or patch applicators are concerned preferably high speed applicators are utilised so as to not detract from a machine speed which ideally is approximately 150 m/min.

Preferably the machine for bag forming is of a kind that relies upon the labelled web being transversely pulled apart by differential speed rollers such as in a machine of the type previously mentioned. A matching arrangement for label application includes a rotary die type slitter at 2 complemented by high speed applicators 3 such as those of Impresstik Pty Limited of Australia (e. g.; a modified version of their model 1000T).

Registration for such an applicator and associated inspection capabilities can be provided by Cam Sensor Technologies Limited of Auckland.

In the examples discussed below bags capable of containing 25kg of powder were produced, each bag had an inner plastics pouch formed from a continuous blown tube, which is cut to length and heat sealed at the base thereof, and then provided with an outer reinforcing layer or layers of Kraft paper or the like.

During production of the bag the blown tube could be inflated, as it passes through the first stage of the production of the bag, and during this stage, one small portion of the continuous tube is preferably perforated on one face only, at a selected position near a resulting edge of the bag, preferably near the position of the open top of the resulting bag. This area would be approximately 100mm by 200mm, or slightly less. That area is then covered by a suitable label, preferably formed of the same material as the bag. For example, if the bag is formed of low density polyethylene, it is preferable that the label is formed of polyethylene although for best adhesion it may be desirable to use high density polyethylene, together with appropriate hot melt or other adhesive to attach the label around its periphery to the selected position of the bag. The labels themselves are preferably pre-perforated in a desired pattern, which pattern preferably does not coincide (i. e.; does not register) with the pattern of the apertures through one face of the bag. The further patterning allows them to be out of register the better.

The size and shape of the apertures is preferably chosen in response to the type of powder or particulate material to be contained within the bag. The label is preferably attached to the bag in such a way that it lies flat in normal use, and is then covered with SUBSTITUTE SHEET (RULE 26)

an outer reinforcing material, such as Kraft paper, or some other plastics layer, or in some cases the bag could be supplied as a single layer pouch. However, in most cases where the bag is to contain, say, 25kg of powder such as milk powder, or fine lactose, or fine pharmaceutical powders, it is preferably that the outer portion of the bag is provided with one or more layers of Kraft paper or other suitable reinforcing material.

The outer covering would then cover over the position of the label, but since Kraft paper is permeable to air, escape of air from within the pouch via the vented label would then pass through the Kraft paper layer or layers to the exterior.

Once the bags have been filled with powder, and the open mouth has been sealed by heat sealing, or by using a pressure sensitive adhesive, then air trapped within the bag can escape via the vented label. This escape of air essentially causes the label to inflate slightly so that the material of the label lifts off the material of the outer surface of the pouch, and thus air from within the bag which is passed into the space between the label and the outer surface of the pouch can escape through the apertures in the label.

If the pressure differential across the bag is such that either the label is covered with a weight, or the air pressure outside is greater than the air pressure inside, then the label will be forced flat against the surface of the pouch, and no air will be able to enter the bag or escape from the bag.

Trials were carried out with bags having labels with slits from lmm to 10mm in length. We found best results with slits of approximately 4mm in length, and believe, if cut outs and round, that apertures of approximately 4mm in diameter would be most suitable for most purposes.

We have also found that by placing the label close to one edge of the bag, better results could be achieved. If the label is placed centrally of the bag it is likely to be covered by another bag, and that may prevent any or sufficient escape of air in a stack condition yet would still have allowed venting at the time of filling.

In our first trial referred to hereafter we slit the bags whilst the continuous tube was inflated, but a preferred alternative is to provide punctures through a small section of both faces of the bag when the bag is pressed flat during production and prior to covering with Kraft paper. In such a case it is preferable that one punctured slit exterior SUBSTITUTE SHEET (RULE 26)

surface of the bag or tube of the bag is provided with the apertured label from a high speed label applicator, and the other punctured or slit exterior surface being covered with an impermeable material such as a patch of self adhesive tape (eg; SELLOTAPETM), or a layer of polyethylene which may, for example, be completely coated with an adhesive such as a hot melt adhesive, so that the adhesive completely covers the apertured surface of the bag where no valve is required.

TRIAL 1-Label Application and Test For Functionality Aims: Functionality Testing Procedure: 1. Four pouches each having an exterior surface of polyethylene are made with different slits (see Table 1). Labels were made from the same permeable film.

2. All pouches were filled with air.

3. All pouches were exposed to the pressure caused by a 10 kg weight and left under pressure for 24 hours.

4. Air release effect was monitored.

Table 1: Pouch No. Slits on Slits on Slits on Slits on Label/No. Label/mm BagNo. Bag/nun 1 2x2 2 1x2 2 2 2 x 2 3-4 1 x 2 3-4 3 2x2 4-5 1x2 4-5 4 2x2 8 1x2 7-8 Results of Trial 1: w Air fully released from pouches 3 and 4 * Traces of residual air in pouch 2 probably caused by uneven distribution of weight.

* Minimal (if any) air release from pouch 1.

TRIAL 2-Bag Making Four bags with the air release labels attached on a PE-pouch mode were made, the apertures in each case (in the bag and in the label) being slits.

Table 2:

Bag No. Slits on Bag Slits on Slits on Slits on No. Ba/mm Label/No. Label/inm 1 1x2 4 2x2 4 2 1x2 5 2x2 5 3 1x2 6 2x2 5 5 1x2 6 2x2 6 TRIAL 3-Bag Performance Evaluation: Trial Aims: 1. To test the release of air from the filled bag with attached label and from the pouch with attached label.

2. To evaluate powder migration into area between label and pouch and, consequently, through slits on label.

Process: 1. Two bags (Nos. 1 and 4 of Table 2) were filled with 25 kg of lactose powder each. The bag filling was so as to ensure maximum air content in the bag. After filling with powder each bag was shaken to ensure maximum volume of air inside. The bags were then sealed. The filled bags were left for 20 hours under weight of a 25 kg bag.

2. Two pouches with labels (No. 2 and 4) were filled with 2 kg of lactose and 12 1 of air. Such filled bags were shaken, dropped from-1 m, thumped so to provide the conditions which can result with high-velocity air passing through slits on pouch and label and carrying some milk powder particles.

Trial Results: 1. Complete air release resulted with bag No. 1 of Table 2. However, there was some residual air present in Bag No. 4 of Table 2. The obvious reason is the positioning of the weight bag that was used for pressure application. This shows

that air release label preferably should be placed as close as possible to the pouch edge.

2. No powder migration was noted for Pouch No. 2 of Table 1 after the dropping, thumbing and shaking. Some powder was accumulated around slits on pouch.

Pouch had been left under the pressure of-10 kg weight for 20 hours, and air had been completely released. This showed that slits were not sealed by powder.

The label of the Pouch No. 4 of Table 1 was blown off during the exercise of shaking, thumbing and dropping. It is the effect of the hot melt used during application having been applied too cold. However, there was the powder carried between label and pouch. It indicates that slits on Pouch 4 of Table 1 are too wide.

TRIAL 4-Pallet Stack Performance The Purpose of Trial The aim of this trial was: To evaluate the performance of bags with the air release label in comparison with control bags placed on equivalent positions on pallet, To evaluate performance of two different label designs of Figures 6A and 6B, each overlying a bag region with simple slits as described by reference to Figure 3B.

Trial Process: Thirteen bags with an air release label were mixed with 50 normal bags in a way that ensured the placement of trial bags in different positions on pallet. The trial pallet was palletised during normal packing process and no alternations of operating conditions were made. The trial pallet was left in storehouse for four days. The trial bags and equivalent control bags were then extracted from pallet for evaluation purposes.

The air release from the pouches of trial bags was evaluated by the comparison with control bags from equivalent positions on pallet. The relative performance was then addressed.

Air Release Performance: 1. The bags with an air release label showed superior air release.

2. There was no distinctive different in performance between 140 mm long labels with four 4.5 mm cross slits and 150 mm long labels with six 4.5 mm cross slits as far as air release is concerned.

3. The evaluation of labels suggested that the design with six cross slits should be the preferred one because of the conveying of powder under label. The longer label with six cross slits gave less opportunity for the powder to reach slits area.

Although the description of the label application to a container (or a formulative material thereof) to act as a bag relates to the application of labels to a bag formed as a pouch from a blown tube (without side seams) it would be appreciated that the label of this invention could also be applied to any other form of plastic bag or pouch, whether formed from a flat sheet, and whether provided with a longitudinal seam, or otherwise.

The air vent label of this invention can be used with bags formed as a simple plastic pouch, or with bags in which a reinforced outer covering is provided over the pouch.

The present invention in preferred forms enables high-speed production of bags by making use of a label applicator to apply an air release label to what is or is to be an exterior surface of the bag which co-acts with an aperture or apertures in the bag to form an effective one way valve for the escape of air.

Finally, various other alterations or modifications may be made to the foregoing without parting from the spirit or scope of this invention as defined in the appended claims.