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Title:
PACKAGING METHODS & APPARATUS
Document Type and Number:
WIPO Patent Application WO/2012/050463
Kind Code:
A1
Abstract:
This invention relates to methods and apparatus for packaging a product within a bag. The method includes the steps of filling the bag with the product through an open end of the bag, and providing for a product security means to be present in the region of where the bag is to be sealed. The method further includes the step of sealing the bag using heat sealing apparatus, whereby the heat sealing apparatus also serves to seal at least a portion of the product security means to the bag, at substantially the same time as the bag is being sealed. Apparatus for performing the method are also described.

Inventors:
RECKIN, Shane Robert (110D Cryers Road East Tamaki, Auckland 2013, NZ)
HENDRA, Denys Anthony (110D Cryers Road East Tamaki, Auckland 2013, NZ)
LEANING, Scott Edward (110D Cryers Road East Tamaki, Auckland 2013, NZ)
Application Number:
NZ2011/000220
Publication Date:
April 19, 2012
Filing Date:
October 07, 2011
Export Citation:
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Assignee:
TECHNOPAK LIMITED (110D Cryers Road East Tamaki, Auckland 2013, NZ)
RECKIN, Shane Robert (110D Cryers Road East Tamaki, Auckland 2013, NZ)
HENDRA, Denys Anthony (110D Cryers Road East Tamaki, Auckland 2013, NZ)
LEANING, Scott Edward (110D Cryers Road East Tamaki, Auckland 2013, NZ)
International Classes:
B65B7/02; B65B51/14; B65B51/30; B65D33/22; B65D33/34
Domestic Patent References:
WO2010055516A12010-05-20
Foreign References:
EP1418132A12004-05-12
NZ516659A2003-10-31
US5103979A1992-04-14
US5319475A1994-06-07
US3745024A1973-07-10
EP0703063A21996-03-27
Attorney, Agent or Firm:
ALLEN & ASSOCIATES (PO Box, Ellerslie, Auckland 1542, 11556, NZ)
Download PDF:
Claims:
We Claim:

1. A method of packaging a product within a bag, said method including the steps of: a) filling the bag with the product through an open end of the bag, b) providing for a product security means to be present in the region of where the bag is to be sealed, c) sealing the bag using heat sealing apparatus, whereby the heat sealing apparatus also serves to seal at least a portion of the product security means to the bag, at substantially the same time as the bag is being sealed.

2. A method of packaging a product within a bag, as claimed in Claim 1, wherein the product security means includes a hot stamping hologram foil.

3. A method of packaging a product within a bag, as claimed in Claim 1 or Claim 2, wherein the product security means includes an OVD.

4. A method of packaging a product within a bag, as claimed in any one of Claims 1 to 3, wherein, the product security means is provided in the form of tape.

5. A method of packaging a product within a bag, as claimed in Claim 4, wherein the product security means is mounted on a first roller, said first roller being adapted to feed the product security means through the region of where the bag is to be sealed.

6. A method of packaging a product within a bag, as claimed in Claim 5, wherein there is provided a second roller for winding up any unused product security means, after the at least a portion of the product security means has been sealed to each bag.

7. A method of packaging a product within a bag as claimed in anyone of Claims 1 to 6, wherein said bag is a plastic bag.

8. A method of packaging a product within a bag as claimed in Claim 7, wherein said plastic bag includes one or more other substrates.

9. A method of packaging a product within a bag as claimed in Claim 8, wherein said one or more other substrates includes aluminium foil.

10. A method of packaging a product within a bag as claimed in Claim 8, wherein said one or "more other substrates includes paper.

11. A method of packaging a product within a bag as claimed in any one of Claims 1 to 10, wherein said bag is used for packaging products intended for human consumption.

12. A method of packaging a product within a bag as claimed in anyone of Claims 1 to 11, wherein said bag is a bulk bag used for packaging food products.

13. A method of packaging a product within a bag as claimed in Claim 12, wherein said bag is a 25kg bag used for packaging milk powder.

14. A method of packaging a product within a bag, as claimed in any one of Claims 1 to 11, wherein said bag is a snack food packet.

15. A method of packaging a product within a bag, as claimed in any one of Claims 1 to 14, wherein said bag is substantially rectangular in shape and includes three closed sides and one open end.

16. A method of packaging a product within a bag, as claimed in Claim 15, wherein at least one of the three closed sides of the bag are formed by the following method: a) providing for a product security means to be present in the region of where said at least one of the three closed sides are to be formed, b) sealing said at least one of the three closed sides using heat sealing apparatus, whereby the heat sealing apparatus also serves to seal at least a portion of the product security means to said at least one of the three closed sides at substantially the same time as said at least one of the three closed sides is being sealed.

17. A method of packaging a product within a bag as claimed in any one of Claims 1 to 16 wherein said heat sealing apparatus includes two sealing bars which come together under pressure.

18. A method of packaging a product within a bag as claimed in Claim 17, wherein one sealing bar is heated and the other is non-heated.

19. A method of packaging a product within a bag as claimed in Claim 17, wherein both sealing bars are heated.

20. A method of packaging a product within a bag, as claimed in any one of Claims 17 to 19, wherein the sealing bars work together to cut out, using heat, the at least a portion of the product security means which is sealed to the bag.

21. A method of packaging a product within a bag, as claimed in any one of Claims 17 to 20, wherein the shape and configuration of the at least a portion of the product security means which is sealed to the bag is determined by the shape and configuration of at least one of the sealing bars.

22. A bag containing a packaged product therein, said product being packaged within the bag according to the method as claimed in any one of Claims 1 to 21.

23. A method of packaging a product within a bag, substantially as herein described and with reference to the accompanying drawings.

Description:
PACKAGING METHODS & APPARATUS

FIELD

This invention relates to packaging methods and apparatus. More specifically, the invention relates to packaging methods and apparatus which provide packaging with tamper evident means (for ensuring the packaging has not been tampered with) and/or product security means (for verifying the authenticity of the packaged product).

The invention may be particularly suitable for use with plastic films or plastic bags used in the packaging industry - and especially so in relation to products intended for human consumption. However, it is to be understood and appreciated that the invention may also have other applications and uses. For example, the invention may also be used in relation to plastic packaging for forensic evidence or electronic equipment, and/or for plastic packaging containing important documents or money. The prior art and possible applications of the invention, as discussed below, are therefore given by way of example only.

BACKGROUND

Ensuring that a product has not been tampered with after being packaged can be of considerable importance, and especially so for products intended for human consumption, such as food, drink and pharmaceutical products.

It is therefore advantageous to be able to provide packaged products with tamper evident means.

An example of where this may be of particular importance is the bulk packaging of food products, which often undergo further processing by the recipient of the product.

For example, powdered or particulate food products such as flour and milk powder are usually bulk-packaged within large 25kg bags. The recipient of such bulk packaged products will want to ensure that each package has not been tampered with prior to its arrival and/or prior to the further processing of the product. The further processing may, for example, include blending the bulk packaged product in with other ingredients and/or subsequently repackaging the product into smaller packages. If subsequent tests showed that the blended product and/or repackaged product contained impurities, but that the bulk packaged product arrived with no evidence of it having been tampered with, then the bulk packaged product may be disregarded as the possible source of the contamination. This would not only serve to exonerate the product manufacturer, but it would be useful in helping to narrow down the possible source of the contamination.

It would therefore be advantageous if there was available a means of providing bulk packaged food products with tamper evident means.

An example of a tamper evident means for use with the packaging of products is described in NZ Patent No. 531014. This patent describes a system for vacuum packaging a product within bags, for example general food products or milk powders. The system described is effective in showing if the contents of any one bag have been tampered with, because the tampered bag would lose its vacuum, and this would therefore be apparent to the person or company receiving or using the bag.

However, the technology described in NZ Patent No. 531014 (whilst usually effective) is somewhat complex, and the machinery required to produce the vacuums is reasonably large, and expensive. This may be prohibitive to some companies wishing to use the technology. Furthermore, the procedure of forming a vacuum in each and every bag may take a reasonable amount of time, and this may therefore reduce the speed or operating capacity of the packaging line.

It would be advantageous therefore if there was available an alternative tamper evident means for use with the packaging of products.

There are many examples in the prior art of tamper evident means for use with the packaging of valuable or important items such as money, documents or forensic evidence. Examples of such tamper evident technologies include: the use of points of weakness in the packaging material; microdot markers; UV fluorescent dies; tamper evident adhesives - and combinations of these technologies. Examples may be found in the following patent documents: US7095324, US4509196, US7008106, US4464158, US6962439 and DE4017759A1.

However, whilst these tamper evident technologies may be effective to some degree, they do not also offer a product security means for validating the authenticity of the packaged product.

As a result, separate product security technologies for use with packaging have emerged, most notably devices such as holograms or Optically Variable Devices (OVD). OVD's are usually attached to packaging materials by the use of adhesives, for example by hot foil stamping or by the use of pre-applied adhesives stuck to a carrier film.

Examples of the use (or manufacture) of OVD's for packaging may be found in the following patent documents: US5913543, US6975765, US7095324 and US4758296.

However, a disadvantage associated with the use of OVD's is that they may be susceptible to being removed from the packaging material, for example by the use of solvents to weaken the adhesives. In such instances, they may then be reapplied to a counterfeit or tampered product.

Alternatively, OVD's may be cut from the packaging material and removed, before being reapplied to a counterfeit or tampered product.

Another disadvantage associated with the use of OVD's is that they do not usually provide, or offer, tamper evident means. That is, the presence of an OVD may indicate that the packaged product is genuine, however the OVD may not be able to also indicate whether or not the packaged product (or the OVD itself) has been tampered with. Hence, if a packaged product (or OVD) has been tampered with, without destroying the integrity of the packaging (or the OVD), then the end user may be none the wiser.

It would be of advantage therefore if there was available packaging which included a product security means which may also serve as a tamper evident means.

It may also be of advantage if such packaging methods and apparatus were able to be used for packaging small packages and/or for use with packaging lines which operate at high speeds or with high volumes, for example small food packages for snack food items such as potato chips. At present such packaged products are not usually provided with tamper evident and/or product security means, primarily because of the cost involved and also because of the high speeds at which such packaging lines operate.

OBJECT

It is an object of the present invention to provide packaging methods and apparatus which go some way towards addressing the aforementioned problems or difficulties, or which at the very least provides the public with a useful choice.

DEFINITIONS

Throughout this specification unless the text requires otherwise, the word 'comprise' and variations such as 'comprising' or 'comprises' will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

STATEMENTS OF INVENTION

According to one aspect of the present invention, there is provided a method of packaging a product within a bag, said method including the steps of: a) filling the bag with the product through an open end of the bag, b) providing for a product security means to be present in the region of where the bag is to be sealed, c) sealing the bag using heat sealing apparatus, whereby the heat sealing apparatus also serves to seal at least a portion of the product security means to the bag, at substantially the same time as the bag is being sealed. It is envisaged that the invention may be particularly useful for the packaging of products intended for human consumption such as food products or pharmaceuticals. However, the invention may also have other uses within the packaging industry. For example, the invention may also be used in relation to packaging for forensic evidence or electronic equipment, and/or for packaging containing important documents or money.

The bag may be any type of bag, and may be of any size or shape, as required or as desired, or as dictated by the type of product(s) to be packaged therein.

Preferably, the bag may be substantially rectangular in shape and include three closed or sealed sides and an open end, through which the bag may be filled.

Preferably, the bag may be a plastic bag, for example a bag made from a polyethylene material or film.

The bag may be comprised of a single laminate of material or a number of laminates of material, such as with co-extruded film.

For example, the bag may be a plastic bag comprising a single layer of plastic material such as polyethylene or it may comprise a number of different laminates of a plastic material(s). Furthermore, the bag may include different types of plastic material, for example it may include a laminate of a gas impermeable film or possibly a laminate which is printed, translucent or opaque.

The bag may include one or more different substrates.

For example, the bag may include a thin aluminium foil - such as those found in snack food packets such as potato chip packets, chocolate, nuts, and the like.

Alternatively, the bag may include one or more layers of paper - such as bags used for the bulk packaging of food products such as milk powders. Such bags are well known within the dairy industry, and several examples may be referenced in NZ Patent No.s 183617 and 242034. The bag may include an RFID tag to enable the tracking of the bag. The use of such FID tags are well known in the prior art, and by those skilled in the art.

Alternatively, or additionally, the bag may include a unique identifier. The type of information which may be included in or on a unique identifier may include: where the bag was packed; what the product is inside the bag; the date and/or time the bag was packed; the Batch Number; the date of dispatch from the factory; the destination of the bag, and so on. Examples of suitable unique identifiers include visible components such as printing or barcodes, or non-visual components such as nano-image screening or components that may only be visible under a certain light, for example an ultra-violet light.

The method of packaging may preferably include the step of filling the bag with the product through an open end of the bag.

Preferably the method may also include the step of providing for a product security means to be present in the region of where the bag is to be sealed.

Preferably, the method may also include the step of subsequently sealing the bag using heat sealing apparatus, whereby the heat sealing apparatus also serves to seal at least a portion of the product security means to the bag, at substantially the same time as the bag is being sealed.

Preferably, only one product security means may be provided in the region of where the bag is to be sealed.

However, it is also within the scope of the invention for a plurality of product security means to be provided in the region of where the bag is to be sealed. In such an embodiment, the heat sealing apparatus may be adapted (or be of sufficient size or dimensions) to seal at least a portion of each product security means to the bag at substantially the same time as the bag is being sealed.

One purpose of the product security means may be to verify the authenticity of the packaged product. Preferably, the product security means may include at least one OVD. Preferably, the product security means may be in the form of a tape.

An example of a suitable product security means may be a hot stamping hologram foil. Such foils are generally made up of a polyester carrier, a number of lacquer layers and an adhesive sizing. During application the heat sealing apparatus activates the very thin lacquer by means of heat and pressure. This causes the lacquer layers to bond with the bag, leaving the carrier film behind (where it may be subsequently collected and recycled or discarded).

Preferably, the product security means may be of a type manufactured and marketed by Leonhard Kurz GmbH & Co KG, of Germany, under its brand name TRUSTSEAL ® .

Any suitable means may be utilised for providing for the product security means to be present in the region of where the bag is to be sealed.

For example, the product security means may be housed on or within an arm that may be lowered when each bag arrives to be sealed, and the arm may subsequently be raised up and out of the way once each bag has been sealed.

In another embodiment, the product security means (preferably in the form of a tape) may be mounted on a first roller, the first roller being adapted to feed the product security means through the region of where the bag is to be sealed.

Furthermore, there may also be provided a second roller for winding up the carrier film, together with any unused product security means, after the at least a portion of the product security means has been sealed to each bag (the carrier film is not destroyed or sealed to the bag during the packaging process).

Any suitable heat sealing apparatus may be utilised for sealing the bag. Examples of suitable heat sealing apparatus for sealing bags generally are those manufactured by our company, Technopak Limited of Auckland, New Zealand. Furthermore, examples of packaging machinery for packaging products within a bag generally are also manufactured by our company, Technopak Limited of Auckland, New Zealand.

Preferably, the heat sealing apparatus may include two sealing bars which come together under pressure.

In one embodiment, the heat sealing apparatus may include one heated bar and one non-heated bar, with the heated bar coming together with the non-heated bar to form the seal, and thus seal the bag - whilst also serving to seal at least a portion of the product security means to the bag at substantially the same time as the bag is being sealed.

In an alternative embodiment, the heat sealing apparatus may include two heated bars which come together under pressure to form the seal, and thus seal the bag - whilst also serving to seal at least a portion of the product security means to the bag at substantially the same time as the bag is being sealed.

Preferably, the heated bars may work together to cut out, using heat, the at least a portion of the product security means which is sealed to the bag.

Preferably, the shape and configuration of the at least a portion of the product security means which is sealed to the bag may be determined by the shape and configuration of at least one of the sealing bars.

In an alternative embodiment, the heat sealing apparatus may be in the form of a RF heat sealer (or RF welder - as such machines are sometimes called).

The heat sealing apparatus essentially serves to heat-weld the product security means to the bag during the process of sealing the bag. In essence, this means that the product security means may be considered to have become part of the bag (or part of the seal of the bag). This is because the effect of heating (and slightly melting) the material of the bag, together with the heating of the product security means, whilst also providing compression, means that the product security means has effectively been encapsulated within and/or heat welded to the bag. This serves to provide a much greater level of adherence of the product security means to the bag, as compared to adhesives which are usually used to attach product security means to packaging.

One advantage of heat sealing the product security means to the bag in this fashion is that it means that the product security means is not able to be removed from the bag without its removal being apparent. For example, the product security means could not be removed by the use of adhesive-removing solvents (which may sometimes affect the integrity of product security means which have been attached by adhesives) because the solvents would not have the ability to break the heat- weld between the product security means and the bag.

Another advantage of the invention is that if the product security means were cut from the bag, it could not be reused in an unauthorised fashion (for example, by applying it to a bag containing counterfeit or tampered product). This is because the heat-weld passing through the product security means would leave a physical impression in the product security means, which would be noticeable. Furthermore, it would be difficult to re-adhere the removed product security means to another bag because the adhesive must be applied, in whole or in part, to the bag material (which would still be welded to the back of the product security means).

Hence, " the invention may be an improvement over existing tamper evident means and product security means, because the product security means not only provides validation of the authenticity of the product, but because it is heat sealed (or heat welded) to the bag, it also provides a tamper evident means for both itself and the packaged product as a whole. Moreover, by heat sealing the product security means to the bag, there is no need to provide a separate tamper evident means, as is often the case. This has savings in cost as well as packaging speed and efficiency.

An important aspect of the invention is that the heat sealing apparatus serves to seal the product security means to the bag at substantially the same time as the bag is sealed. Preferably the heat sealing apparatus serves to seal the product security means to the bag simultaneously as the bag is sealed. Hence, an advantage of the present invention is that it allows for the application of the product security means to the bags at the same speed as the bags are ordinarily packaged and sealed. Hence, the packaging methods and apparatus of the present invention may be utilised with high speed packaging lines, for example those used for the packaging of pharmaceuticals or small food packets. The invention therefore allows for such packaged goods to enjoy the benefits of having product security means applied thereto (which would not ordinarily be the case).

Another advantage of the present invention is that it removes the step of separately having to apply a product security means to a bag. This has savings in time, efficiency and therefore cost. Furthermore, additional apparatus is not required to separately apply product security means to bags, for example prior to filling and sealing the bags.

In one embodiment of the present invention, it is also envisaged that at least one of the three closed sides of the bag may also be provided with product security means. In such an embodiment, the at least one of the three closed sides of the bag may preferably be formed by the following method: a) providing for a product security means to be present in the region of where the at least one of the three closed sides are to be formed, b) sealing the at least one of the three closed sides using heat sealing apparatus, whereby the heat sealing apparatus also serves to seal at least a portion of the product security means to the at least one of the three closed sides at substantially the same time as the at least one of the three closed sides is being sealed.

Preferably, such an embodiment may allow for all three closed sides of the bag to be sealed in this fashion. It may be appreciated that having all four sides of a sealed bag incorporating product security means renders it even more difficult for the bag to be tampered with, or for the authenticity of the product packaged within the bag to be compromised. Such a bag may be particularly useful for the packaging of important small items such as pharmaceuticals.

In such an embodiment of the invention, the product security means may be applied during the formation of the bag, for example during the conversion of plastic film to plastic bags.

PREFERRED EMBODIMENTS

The description of a preferred form of the invention to be provided herein, with reference to the accompanying drawing, is given purely by way of example and is not to be taken in any way as limiting the scope or extent of the invention.

DRAWINGS

Fig 1 : is a view of a bag packaged according to one possible embodiment of the present

invention,

Fig 2: is a view of a bag packaged according to another possible embodiment of the present invention,

Fig 3: is a top view showing the apparatus for heat sealing the bag illustrated in Fig 1 Fig 4: is a front view of the apparatus illustrated in Fig 3, and

Fig 5: is a front view showing the apparatus for heat sealing the bag illustrated in Fig 2.

DESCRIPTION OF PREFERRED EMBODIMENTS

Having regard to Fig 1, there is shown a bag packaged according to one possible embodiment of the present invention.

The bag 1 is the inner plastic bag used for the bulk packaging of milk powder 30, and it is designed to hold 25kg of milk powder 30.

The inner plastic bag 1 would usually sit within an outer paper bag comprising one or more plies of a paper material - but for convenience of illustration only, the outer paper layers are not shown. In use, the inner plastic bag 1 is designed to be filled with milk powder 30 and the outer paper bag is designed to provide a covering for the inner plastic bag 1 during storage and/or transportation etc.

It is also envisaged however that the bag 1 may be utilised on its own, that is, without being housed within a paper outer bag.

Generally speaking, most inner plastic bags 1 of the type illustrated in Fig 1 are made up of anywhere between 1-12+ laminates of an extruded plastics material(s), for example polyethylene. As a general rule of thumb, the plastic bag 1 should include at least five layers of extruded plastics materials in order to provide the bag 1 with the required carrying strength and/or to render the bag substantially or wholly gas impermeable.

Alternatively or additionally, the bag 1 may include one or more specific plastic(s) layers designed to render the bag 1 gas impermeable. An example of such a plastics material would be an EVOH polymer.

The film comprising the bag 1 is formed from a blown film extrusion process. Such a process will be well known by those skilled in the art and it is not intended therefore to describe this process in any great detail herein.

The film formed by the blown film extrusion process is subsequently converted into the bag 1 by known conversion processes. Examples of suitable conversion machinery for the purposes of bag making are those manufactured by Windmoeller and Hoelscher of Germany (especially for the dairy industry) and Totani Corporation of Japan.

The bag 1 is thus formed by heat sealing the plastic film along two sides to produce the side seals 2, 3 and also heat sealing along the bottom to produce the bottom seal 4. The top of the bag 5 is left open and the formed bags may then be shipped to the end user - in this case to the dairy factory which will be packaging the milk powder 30.

The bag 1 is filled with the milk powder 30 and subsequently sealed to form the top seal 7. The top seal 7 incorporates a product security means in the form of a hologram foil 6. The bag 1 is sealed using heat sealing apparatus generally indicated by arrow 10 in Fig 3 and Fig 4.

The method of sealing the bag 1 will now be described in relation to the embodiments illustrated in Fig 3 and Fig 4.

Fig 3 is a top view showing the how the bag 1 may be sealed. The open top 5 of the bag 1 is shown just after the bag 1 has been filled with milk powder 30. The region of where the bag 1 is to be sealed is generally indicated by arrow 9.

There is provided a product security means in the form of tape 11. The tape 11 is a hot stamping hologram foil (which incorporates an OVD). Such product security means are advantageous because they are extremely difficult, if not impossible, to successfully imitate or reproduce. Furthermore, the holographic nature or structure of the tape 11 shown is such that it will be destroyed by attempts to remove it or tamper with it.

The tape 11 illustrated is manufactured and marketed by Leonhard Kurz GmbH & Co KG, of Germany, under its brand name TRUSTSEAL ® .

The tape 11 includes a polyester carrier film - which serves to support the otherwise fragile and/or brittle hologram foil. The hologram foil is approximately 4 microns thick and the polyester carrier film is approximately 60 microns thick.

The tape 11 is mounted on a first roller 12 positioned on one side of the bag 1, the first roller 12 being adapted to feed the tape 11 through the region 9 of where the bag 1 is to be sealed.

There is also provided a second roller 13 positioned on the other side of the bag 1, for winding up the tape 11 (and/or carrier film) after the application of the product security means 6 to the bag l .

There is provided heat sealing apparatus which includes a first (or rear) heated sealing bar 14, situated on one side of the bag 1, and a second (or front) heated sealing bar 15, situated on the other side of the bag 1. The tape 1 1 is fed through the region between the bag 1 and the second heated sealing bar 15.

The two heated sealing bars 14, 15 come together under pressure to form the seal 7, and thus seal the bag 1 - whilst also serving to simultaneously seal a portion 6 of the hologram foil, or tape 11 , to the bag 1.

The heated sealing bars 14, 15 work together to cut out, using heat, the portion 6 of the hologram foil which is sealed to the bag 1.

The shape and configuration of the portion 6 of the hologram foil which is sealed to the bag 1 is determined by the shape and configuration of the second heated sealing bar 15. This is best illustrated in Fig 4 (which is view of the embodiment illustrated in Fig 3, looking in the direction of the arrow 8).

In Fig 4, the shape of the second heated sealing bar 15 is substantially elongate and rectangular. This therefore determines that the shape and configuration of the portion 6 of the hologram foil which is sealed to the bag 1 is similarly substantially elongate and rectangular. This is because the second heated sealing bar 15 (in conjunction with the first heated sealing bar 14) heats the very thin lacquer contained within the hologram foil by means of heat and pressure. This causes the lacquer layers which are heated to bond permanently with the bag 1, leaving the carrier film behind (as well as the unused or unheated hologram foil).

Hence, the seal 7 (which includes the portion 6 of the hologram foil applied to the bag 1) is of substantially the same shape and configuration as the sealing face 16 of second heated sealing bar 15.

In Fig 3, it may be seen that the heated sealing bars 14, 15 are slightly wider than the bag 1 to ensure that the bag is properly sealed.

In an alternative embodiment of the invention, the shape and configuration of the second heated sealing bar 15 may be substantially the same as the shape and configuration of the tape 11, whereby substantially the whole of the hologram foil is sealed to the bag, rather than just the portion 6 of the tape 11 which is cut out (using heat) - as illustrated in the embodiments in Fig 1, Fig 3 and Fig 4.

It may be appreciated that the heat sealing apparatus 10 serves to seal the hologram foil 6 to the bag 1, at substantially the same time (or simultaneously) as the bag 1 is being sealed.

Hence, an advantage of the present invention is that it allows for the application of the hologram foil 6 to the bags 1 at the same speed as the bags 1 are ordinarily packaged and sealed.

Fig 2 illustrates a bag 20 packaged according to another possible embodiment of the present invention.

The bag 20 is a small 150gm potato chip packet used for packaging potato chips 19. The bag 20 includes several layers of a plastic material bonded to a thin inner layer of aluminium foil.

The bag 20 is formed by heat sealing plastic film along two sides to produce the side seals 21, 22 and also heat sealing along the bottom to produce the bottom seal 23. The top of the bag 24 is left open and the formed bags may then be shipped to the end user - in this case to the food processing plant where the potato chips are to be packaged.

The bag 20 is filled with potato chips 19 and subsequently sealed to form the top seal 25. The top seal 25 incorporates a product security means in the form of a hologram foil 26. The bag is sealed using heat sealing apparatus, part of which is generally indicated by arrow 27 in Fig 5.

The method of sealing the bag 20 will now be described in relation to the embodiment illustrated in Fig 5.

Fig 5 is a front view showing the how the bag 20 may be sealed.

The bag 20 is shown just after the bag 20 has been filled with potato chips 19. The region of where the bag 20 is to be sealed is generally indicated by arrow 28. There is provided a product security means in the form of tape 29. The tape 29 is a hot stamping hologram foil (which incorporates an OVD) manufactured and marketed by Leonhard Kurz GmbH & Co KG, of Germany, under its brand name TRUSTSEAL ® (the same as that illustrated in Figs 1, 3 and 4).

The tape 29 is mounted on a first roller 31 positioned above the bag 20, the first roller 31 being adapted to feed the tape 29 through the region 28 of where the bag 20 is to be sealed.

There is also provided a second roller 32 positioned below the top of the bag 20, the second roller 32 being adapted to wind up the tape 29 (or carrier film) after the application of the hologram foil 26 to the bag 1.

The heat sealing apparatus 27 illustrated in Fig 5 only shows the front heated sealing bar 33 (the rear heated sealing bar will be on opposite side of the bag 20 - as per the arrangement illustrated in Fig 3).

The front heated sealing bar 33 is adapted to come together, under pressure, with the rear heated sealing bar (not shown) to form the seal 25, and thus seal the bag 20 - whilst also serving to simultaneously seal a portion 26 of the hologram foil, or tape 11 , to the bag 1.

That is, the front heated sealing bar 33 and the rear heated sealing bar work together to cut out, using heat, the portion 26 of the hologram foil which is sealed to the bag 1.

The shape and configuration of the portion 26 of the hologram foil which is sealed to the bag 1 is determined by the shape and configuration of the front heated sealing bar 33.

That is, the front heated sealing bar 33 comprises a central square portion 34, with a substantially elongate rectangular portion 35 extending from each side of the square portion 34. This results in the shape of the portion 26 of the hologram foil which is sealed to the bag 20 - as this is the shape cut out of tape 29.

The bag 20 is heat sealed closed in the region determined by the heat seal 25 (which does not include any hologram foil) and the region 26 (which does include hologram foil).

The rear heated sealing bar (not shown) is of a substantially rectangular shape, and is larger than the front heated sealing bar, whereby the dimensions of the front heated sealing bar 33 fit entirely within the dimensions of the rear heated sealing bar.

An advantage of the embodiment illustrated in Fig 2, as compared to the embodiment illustrated in Fig 1, is that a larger amount or area of hologram film is applied to the bag. This makes the hologram foil more visible and also allows for a larger area of OVD to be displayed - which renders the hologram foil more effective.

It may be appreciated that the heat sealing apparatus 10, 27 essentially serve to heat- weld the portions of the hologram foil 6, 26 to the bags 1, 20 during the process of sealing the bags 1, 20. In essence, this means that the portions of the hologram foil 6, 26 may be considered to have become part of the bags 1, 20. This is because the effect of heating (and slightly melting) the material of the bags 1, 20, together with the heating of the hologram foil tape 11, 29, whilst also providing compression, means that the portions of the hologram foil 6, 26 have effectively been encapsulated within and/or heat welded to the bags 1, 20 respectively.

This serves to provide a much greater level of adherence of the portions of the hologram foil 6, 26 to the bags 1, 20, as compared to adhesives which are usually used to attach such product security means to packaging.

One advantage of heat sealing the portions of the hologram foil 6, 26 to the bags 1, 20 in this fashion is that it means that the portions of the hologram foil 6, 26 are not able to be removed from the bags 1, 20 without their removal being apparent. For example, the portions of the hologram foil 6, 26 could not be removed by the use of adhesive-removing solvents (which may sometimes affect the integrity of product security means which have been attached by adhesives) because the solvents would not have the ability to break the heat-weld between the portions of the hologram foil 6, 26 and the bags 1, 20.

Another advantage of the invention is that if the portions of the hologram foil 6, 26 were cut from the bag 1, 20 they could not be reused in an unauthorised fashion (for example, by applying the portions of the hologram foil 6, 26 to another bag containing counterfeit or tampered product). This is because the heat- weld passing through the portions of the hologram foil 6, 26 would leave a physical impression in the portions of the hologram foil 6, 26, which would be noticeable. Furthermore, it would be difficult to re-adhere the removed portions of the hologram foil 6, 26 to another bag because the adhesive must be applied, in whole or in part, to the bag material (which would still be welded to the back of the portions of the hologram foil 6, 26).

Hence, the invention may be an improvement over existing tamper evident means and product security means, because the product security means of the present invention not only provides validation of the authenticity of the product, but because the product security means is heat sealed (or heat welded) to the bag, it also provides a tamper evident means for both itself and the packaged product as a whole. Moreover, by heat sealing the product security means to the bag, there is no need to provide a separate tamper evident means, as is often the case. This has savings in cost as well as packaging speed and efficiency.

Another advantage the packaging methods and apparatus of the present invention is that the invention may be utilised with high speed packaging lines, for example those used for the packaging of pharmaceuticals or small food packets. The primary reason for this is because the present invention allows for the application of the hologram foils 6, 26 to the bags 1, 20 at the same speed as the bags 1, 20 are ordinarily packaged and sealed.

The invention therefore allows for a larger array of packaged goods to become commercially viable to being provided with the benefits of having product security means (and/or tamper evident means) applied thereto (which would not ordinarily have been the case).

Another advantage of the present invention is that it removes the step of separately having to apply a product security means to a bag. This has savings in time, efficiency and therefore cost. Furthermore, additional apparatus is not required to separately apply product security means to bags, for example prior to filing and sealing the bags. VARIATIONS

While the embodiments described above are currently preferred, it will be appreciated that a wide range of other variations might also be made within the general spirit and scope of the invention and/or as defined by the appended claims.