EP1347924A1

EP1347924A1 - A folded package and a method of making such a package

Info

Publication number: EP1347924A1
Application number: EP01980205A
Authority: EP
Inventors: Christensen Kaj; Berg M Ller Jens; Brunh J Andersen Torben
Original assignee: Wecapack AS
Current assignee: Wecapack AS
Priority date: 2000-11-06
Filing date: 2001-11-01
Publication date: 2003-10-01
Anticipated expiration: 2021-11-01
Also published as: DE60105060T2; ATE273879T1; DK1347924T3; TR200402788T4; AU2002212106A1; PT1347924E; WO2002036458A1; ES2227294T3; DE60105060D1; EP1347924B1

Abstract

The invention relates to a folded package and a method of making a package preferably for nutritious and non-nutritious products, including foods and beverages or the like. An object of the inventon is to provide a package, where the package may be provided with a print before the package is formed, and where the forming may take place substantially by cold forming so that the print is not affected, and where the package is suitable for receiving a tight-fitting closing means. The novel and characteristic aspect of the method of making a package is that it comprises a sheet comprising at least a layer of plastics to which an amount of inorganic powder material has been added, and that the making of the package comprises at least a combination of punching of the sheet in blanks (10), folding of at least a bottom (4) and at least a side (14), welding and forming of at least a collar (22). Owing to the inorganic powder material and owing to the poor heat effect, minimum shrinkage and very high reproducibility are achieved.

Description

A folded package and a method of making such a package

The invention relates to a folded package and a method of making such a package, preferably for nutritious and non- nutritious products, including foods and beverages or the like, said, package comprising at least a bottom and a least a side, said package being formed of at least a sheet .

It is known e.g. from the German Offenlegungsschrift DT 2641162 to fold a package which is intended for the storage of food products. This package is made of a rigid cardboard material which is coated with a fat and moisture impermeable layer. The bottom section is folded and glued to the side member which is assembled by gluing where the ends overlap. As the ends overlap, one end face in the overlap is exposed to the internal side of the package, i.e. the side which gets in contact with the product to be packaged. Precisely because the cardboard material is merely coated with the fat and moisture impermeable layer, the cardboard material at the end face is exposed directly, for which it is not intended. The packaged product "attacks" the cardboard, and especially so if the product is butter or margarine, for which rea- son such a package is only intended for short term storage and only for specific products.

The same problems are known from numerous known types of folded packages, just as shown in DT 2641162, where use is always made of a material substantially based on board, paper, cardboard or a similar material having cellulose fibres as the main component. At joints of the material where the overlapping ends are glued together, the contents of the package will get in contact with the un- coated cardboard or board. This applies no matter whether board having a plastics and/or an aluminium coating for cocoa milk or juice, or so-called liquid cardboard for milk products are involved. It is moreover characteristic of these packages that they cannot be used for e.g. butter or margarine, which contains acid that especially attacks the exposed board at the overlaps .

Other types of packages for food products are made of plastics which is shaped by means of extrusion/thermoforming, injection moulding, in-form or in- mould labelling processes.

The thermoformed plastics packages have a disuniform wall thickness because of the shaping process, which requires a relatively extensive quality control, and moreover the manufacturing process causes the finished package to have an unnecessarily great wall thickness in areas which are not deformed very strongly in the shaping. This unneces- sary wall thickness is an economic strain of course. Subsequently, the package must be provided with e.g. a label or a board shell which is provided with pre-printed information, advertisement or the like, as the material cannot be pre-printed because of the heat and because of the deformation.

Printing directly on the formed package gives a much too poor result with the known printing techniques, which would have an adverse effect on the sales of the goods in the package. Thus, a further highly cost-adding and negative aspect is involved.

In in-form labelling, a pre-printed label is placed in the deep drawing tool, following which the heated plas- tics is e.g. sucked into shape and fuses with the label. This process is expensive, because the labels have to be made and handled separately - including being placed in the deep drawing tool .

In injection moulding and in-mould labelling the wall thickness is very uniform, but the product is considerably more expensive to manufacture relative to a package made by the thermoforming process. The problems of the injection moulded packages are the same as with the ther- moformed ones. That is that they cannot be pre-printed, and that this must be done after forming, whereby the quality of the print gets much too poor. Alternatively, they must be provided with an expensive label or board shell. In-mould labelling, which is injection moulding with a pre-printed label placed in the mould, involves the same drawbacks as are stated above for in-form labelling. That is that the process is expensive, because the labels must be made and handled separately - including being placed in the mould.

GB 2,018,227 discloses a container for take-away foods. The package is punched from a plastics or metal sheet and folded into shape, said shape being maintained as the sides of the container have projections which are caused to engage at the folding. The recovery property of the plastics keeps the container in shape. With known and suitable plastics types for food product use, the folding can only be partial and without sharp folds . This is due to the same recovery property of the material. When a plastics sheet is folded, the sheet can be bent max. 180 degrees. At 180 degrees the two sides of the, fold meet. To achieve a permanent deformation with sharp folds, the material would have to be bent considerably more, which, of course, is not possible for physical reasons. Therefore, the container has rounded sides and soft folds. Further, the patent does not state that there may be a lid for the container. A lid/wafer would not form a tight seal either, as the folds are too inaccurate, and thereby also the shape of the opening of the container is inaccurate. So even if the overlaps were glued, and an attempt was made with a lid, then the container would not be suitable for anything but storage of the contents for minutes, rather than hours, let alone days.

Further, GB 2,273,093 discloses a container which is made by folding of plastics, and where the sides have projections which are caused to engage at the folding, whereby the shape is retained and fixed owing to the recovery property of the plastics. The figures of the document show the folds as sharp creases, which is not possible with known plastics types by ordinary folding. As mentioned above, this would require bending beyond 180 de- grees. The upward opening gets very inaccurate, and therefore the container is not suitable for the application of a tight-sealing lid/wafer. Thereby, it is not suitable for the storage of contents that may not be exposed to the ambient air, which is the requirement e.g. with many types of processed foods.

An object of the invention is to provide a package of a plastics sheet material as well as a method of making such a package, which is suitable inter alia for nutri- tious and non-nutritious products, including foods and beverages or the like, wherein the package may be provided with a print before the package is formed, and wherein the forming may take place substantially by cold forming so that the print is not affected. A further ob- ject is to provide a method and a package, wherein the forming may take place substantially by cold forming, and wherein the package is suitable for receiving a tight- fitting lid/wafer. Another object is to provide a method and a package wherein it is not necessary to apply a label or the like and/or use another subsequent cost-adding process. Still another object is to provide a method and a package, wherein the package protects the contents better than known board-based packages, which may improve the life of the contents, both in total and on the shelf at the shop, and/or which may mean that the share of preservatives in the contents may be reduced. A further object is to provide a method of making a package where the package need only be "erected" (folded and joined) imme- diately before it is filled.

The novel and characteristic aspect of the method of making a package is that it comprises a sheet comprising at least a layer of plastics to which an mount of inorganic powder material has been added, and that the making of the package comprises at least a combination of at least the following processes:

a) At least partial punching of the sheet in blanks from a roll or a sheet supply

b) Folding of at least a bottom and at least a side

c) Welding of at least a sheet and at least a side

d) Forming of at least a collar.

Welding is taken to mean a heating whereby the two ends or two parts fuse together, or that an applied glue is activated, so-called hot gluing, or a hot melted substance is applied that adheres and/or seals the ends or the parts together, or another similar process.

A collar may comprise a formed edge, face, side or a termination which is suitable for cooperating with a lid, package, wafer or other similar closing means. A collar may be used for increasing the strength, rigidity and/or reproducibility of a package, a lid, etc.

Making the package of a sheet comprising at least a layer of plastics to which an amount of inorganic powder material has been added, provides the technical effect that the properties of the plastics layer are changed. The re- suit is inter alia that the modulus of elasticity and the yield point are different in tension and in compression. Folding causes the recovery of the material to be considerably less - it becomes dead - and sharp folds and creases may be made. Hereby, after suitable punching, the package may be folded to the desired shape, which is fixed e.g. by welding. The welding covers a very limited area, so that prints, if any, are not disturbed. Owing to the material of the inorganic powder material and owing to the poor heat effect, minimum shrinkage and very high reproducibility are achieved. The reproducibility of form, shape and measure is important owing to the quality of the package. Forming a collar on the package imparts additional rigidity, and makes the package suitable for receiving e.g. a tight-fitting lid or wafer. Since the inorganic powder material has been added to the plastics, and thereby been encapsulated, nothing happens if two faces overlap, and one obtains an end face which is exposed relative to the product which the package is to contain. The forming of at least a collar may comprise rolling, thereby providing in a simple manner a strong and stabilizing collar which comprises several layers.

The forming of at least a collar may comprise hot forming of the shape of the collar, so that e.g. sharp edges may be made for engagement with e.g. a lid or a container.

In an expedient embodiment, the package may comprise several parts, including parts having means for closing the package, said parts being preferably made in the same manner as stated above, whereby the same advantages may be achieved for all the parts.

The sheet may be provided with a print prior to the punching, so that printing may take place before the package is erected. Thereby, the printing may be carried out with a much higher quality than is possible on a formed package. In addition, it is much less expensive.

The manufacture may comprise hot forming of double-curved edges and/or faces, thereby allowing more sophisticated shapes to be achieved than by pure folding. By limiting the area of the hot forming, the low shrinkage and the high reproducibility are maintained.

In an expedient embodiment, at least one side may be separated from the at least one bottom at start, as well as be at least partly folded and joined separately, following which the at least one side and the at least one bottom are joined. Hereby, more complex shapes may be provided than by using contiguous side and bottom. Punched blanks may be stacked on a pallet having a fixture intended for the geometry concerned, and which is suitable for the package to be erected immediately prior to filling. Hereby, considerable savings may be achieved in the transport of packages, as non-erected packages take up considerably less space, and the packages need not be stackable. The same advantage is also achieved in the storage of packages. In addition, a considerably larger number of packages may be provided at the filling unit, and magazines do not have to be refilled very frequently.

The novel and characteristic aspect of the package comprises the features that it is made of least a sheet com- prising at least a layer of plastics to which an amount of inorganic powder material has been added, and that the package is substantially formed by folding and welding, and that the package comprises at least a collar which is suitable for receiving means for closing the package. This provides a package having minimum shrinkage and very high reproducibility. Since the inorganic powder material has been added to the plastics and thereby substantially encapsulated, nothing happens if two faces overlap and one obtains an end face which is exposed relative to the product which the package is to contain.

The sheet may comprise at least a cover layer of plastics which may e.g. have a greater resistance or strength than the rest of the sheet. Or e.g. another colour or a better quality of plastics in the cover layer may be used.

The sheet may be provided with a print which has been applied before the forming of the package, thereby allowing the printing to be carried out with the sheet in a plane state so that known methods of high quality printing may be used. Furthermore, reduced process waste is achieved, since the "lattice" from the subsequent punching in the plastics type concerned may be reused without any prob- lems, as printing on the "lattice" may be omitted.

The package may comprise several parts, including at least a part provided with means for closing the package, said parts being preferably made of the same type of ma- terial. Thereby, all parts may be made in the same quality and with the same advantages .

The folded package may comprise at least a barrier layer in the sheet, which means that in some types of packages there is no need for additional protection against sun light, water and oxygen. This protection is simply incorporated in the sheet from which the package is folded. Moreover, the part of the sheet remaining after punching may be reused without any problems, which has so far not been the case with residual material from e.g. thermo- forming of packages . In the traditional methods of making a package, residual material may also be reused, but only if there is no ink on the sheet since this may contain free radicals. The problem of reusing materials in which there is a layer of light-protecting plastics, is that the light protecting layer is frequently black and can only constitute about 10% of the total thickness of the sheet, since, otherwise, the black can be seen through the white outer layers. In a thermoforming process, about 50% residual material is left from the thermoforming process. If 50% residual material is incorporated in a 10% layer, it is not economically profitable since about 40% of the plastics material has to be discarded. This in order to satisfy the consumer's wish for e.g. a 100% white cup.

The sheet may comprise at least a layer of plastics which is foamed, whereby the weight of the package may be reduced, while saving material, and a better thermal insulation is achieved.

The package may include a collar intended for a snap lid. This gives the possibility of using the ordinary type of lids which are typically used for table margarine and similar products.

In another embodiment, the package may include a collar intended for a snap-in lid, and in still another embodiment, be intended for a press lid. The package may thereby be used together with all common types of lids.

The sheet may comprise at least a cover layer which pref- erably comprises at least an olefin, said material being suitable for reuse.

The inorganic powder material may preferably comprise lime and/or talc, which is inexpensive, and which is suitable for the addition to plastics in common extruders .

The at least one layer to which inorganic powder material has been added, may constitute at least 75% of the total thickness of the sheet. Hereby, a relatively large amount of powder may be achieved, which reduces the price. At the same time, the amount of powder is favourable for the reproducibility of the package. The amount of inorganic powder material may constitute at least 20 per cent by weight of the at least one layer, thereby making the sheet foldable .

The amount of inorganic powder material may preferably constitute at least 50 per cent by weight of the at least one layer, which is particularly favourable for the fold- ability of the sheet, just as shrinkage is reduced.

The invention will be described more fully below by means of drawings which show examples of embodiments of the invention:

Fig. 1 shows a section of a folded package

Fig. 2 shows a section of a folded package

Fig. 3 shows a bottom and a side of a non-folded package

Fig. 4 shows a section of a folded package with a snap- in lid

Fig. 5 shows a section of a folded package with a snap lid

Fig. 6 shows a section of a folded package with a press lid

Fig. 7 shows a section of a folded package

Fig. 8 shows the principle in a pallet having a fixture, seen obliquely from above. Fig. la shows a sheet which consists of a single layer 3 of plastics to which an amount of inorganic powder material has been added. The plastics material may be an ole- fin, while the powder material may e.g. be lime or talc.

Fig. lb shows a sheet which consists of a single layer 3 of plastics to which an amount of inorganic powder material has been added, and which is provided with a cover layer 5 of plastics on its one side.

Fig. lc shows a sheet which consists of a single layer 3 of plastics to which an mount of inorganic powder material has been added, and which is provided with cover layers 5' and 5" of plastics on both sides.

Fig. Id shows a sheet which consists of a single layer 3 of plastics as well as an integrated barrier layer 7, which may e.g. be black pigment, black plastics, aluminium foil, etc.

Fig. le shows a sheet which consists of a single layer 3 of plastics to which an amount of inorganic powder material has been added, and which is provided with cover layers 5' and 5" of plastics on each side and addition- ally provided with a barrier layer 7.

The sheet may be made e.g. by lamination or by co-extrusion and may comprise as many or as few layers as is required by the actual packaging need.

Fig. 2 shows a section of a folded package which is formed of a single piece of sheet. In this embodiment, there is an edge bent from the bottom 4 , said edge forming a foot 6 on the package at the transition to a side 14. The side 14 is terminated with a collar 22, which is formed by rolling in this case. At the points where the sheet may have overlapping ends, which is not shown in the figure, these are welded or e.g. hot-glued to each other. Differences in level owing to overlap may be equalized by hot forming or bevelling. Instead of overlap, ends may be joined edge to edge and be welded or glued. The foot 6 and/or the collar 22 may be fixed by supply of heat or by gluing.

Fig. 3 shows a variant of a punched bottom 4 and a non- punched side 14, where the bottom 4 and the side 14 may be provided with a print. When the package, immediately prior to filling, is to be folded, the bottom 4 and the side 14 are arranged in a folding machine and folded, so that an edge is bent down from the bottom 4, and the side 14 is bent upwards and moved round the bottom . When the package has been folded, it is welded or hot-glued e.g. by means of welding pads that may be mounted in connec- tion with the folding machine. After completed joining, the package is ready for use and may be advanced to a filling station.

The bottom 4 and the side or sides 14 may likewise be partly folded and partly welded, followed by additional folding and welding, just as also a collar or a foot as well as double-curved edges and/or faces may be partially formed in the course of the process . The constituent process may be combined in numerous ways according to the invention, which merely depends on the concrete design selected for the package .

It should be stressed here that other shapes may of course be provided as needed or desired. What is contem- plated here is not just how the sheet is formed with a bottom 4 and a side or sides 14, but also a more overall level in terms of the design of the package. According to the invention, packages may be made in all possible shapes, such as round, oval, conical, rectangular shapes, etc .

Moreover, as shown in figs. 4, 5 and 6, packages 2 intended for various types of lids 18, 20 may be made.

Fig. 4 shows a package which comprises a so-called snap- in lid 18. This type has the advantage that the closure may be air-tight, and the trapped air contributes to stabilizing the package. Further, insertion of a wafer may be omitted with a snap-in lid, if the sheet is provided with a barrier layer 7. A bottom 4 has a downwardly bent edge about which a side 14 is folded. Lowest, the side 14 and the bottom 4 engage and together form a foot 6. The side 14 and the bottom 4 are welded or glued together at the foot 6. The side 14 is upwardly terminated with a collar 22. The collar 22 may be formed by rolling and subsequent hot forming. The rolling causes the sheet to be at least double-layered, so that there will be sufficient material to work with in the hot forming. This al- lows a precise collar 33 to be hot-formed, which is suitable for receiving e.g. a lid. On the other hand, the package may of course also constitute a lid or part of a lid.

Fig. 5 shows a package which comprises a so-called snap lid 20. In the embodiment shown, a bottom 4 has a downwardly bent edge which is in engagement with a correspondingly bent edge on a side 14 so as to form a foot 6. The side 14 and the bottom 4 are welded or glued together at the foot 6. Upwardly, the side 14 is provided with a collar 22 which is suitable for receiving a snap lid 20. The collar 22 may be hot-formed in shape to achieve a greater precision of the position of the active edge on the collar 22.

Fig. 6 shows a package which comprises a so-called press lid 21. In the embodiment shown, a bottom 4 has a downwardly bent edge which is in engagement with a corre- spondingly bent edge on a side 14 so as to form a foot 6. The side 14 and the bottom 4 are welded or glued together at the foot 6. Upwardly, the side 14 is provided with a collar 22 which is suitable for receiving a press lid 21. The collar 22 may be hot-formed in shape to achieve greater precision.

The lids 18, 20, 21 may be made in the same manner and of the same material as the sides 14 and the bottom 4, i.e. by a combination of punching, folding, welding and fold- ing of at least a collar.

Fig. 7 shows a variant of the package which is precisely suitable for use as a lid. The package comprises a bottom 4 which is connected to a side 14, said side 14 being formed downwardly with a collar 22 which is formed by rolling.

Fig. 8 shows a preferred embodiment of a pallet 24 having a fixture 26. The pallet 24 is intended to be fixed in connection with both a punching process, a folding process and a filling process. It is provided with one or, as shown here, several fixtures 26 intended for precisely the geometry in which the blank 10 concerned is made. Blanks 10 may be bottoms 4 and/or sides 14 which may be contiguous. The fixture 26 may be adjustable so that the pallet 24 may be adjusted to other blanks 10. The pallet 24 may be used in filling areas where strict requirements on the pallet are frequently made. What is contemplated here is e.g. that the pallet must be capable of being cleaned in a safe manner. In the figure, the pallet 24 is provided with a bottom 28 that may be raised so that the upper blanks 10 are always at the same height. Instead of punched blanks 10, the sheet may be in roll form, where the shape of bottoms 4 and/or sides 14 is partly punched. That is that between the roll and bottoms 4 and/or sides 14 there is a plurality of thin connections, which may easily be torn at or on the machine which is to "erect" the package .

The folded package may be made of sheet that has been punched into blanks of a sheet-shaped or coiled material prior to folding, which provides the possibility of having the stock material in a form which is suitable for the other steps of production. The sheet may be composed of several layers which are optionally laminated in sheet form or co-extruded, • while other sheets may be coiled.

In an embodiment, the package may be made of a plastics mono-sheet. Mono-sheet is taken to mean a product having the desired properties, while the material is inexpensive, and the residual material can readily be used again.

The package may also be formed of a plastics sheet consisting of several layers. It is hereby possible to use a sheet which consists of e.g. an internal layer, a barrier layer of aluminium foil and an outer layer. The layered structure may hereby be adapted to the purpose which the package is to serve.

The package may comprise means for electronic identifica- tion, e.g. a microchip. The package may moreover comprise means for closing the package, e.g. a lid, a wafer or a fill seal, etc.

Claims

Patent Claims

1. A method of making a package preferably for nutritious and non-nutritious products, including foods and beverages or the like, said package comprising at least a bottom (4) and at least a side (14) , said package being formed of at least a sheet, characterized in that the sheet comprises at least a layer (3) of plastics to which an amount of inorganic powder material has been added, and that the making of the package comprises at least a combination of at least the following processes:

a) At least partly punching of the sheet in blanks

(10) from a roll or a sheet supply

b) Folding of at least a bottom (4) and at least a side (14)

c) Welding of at least a bottom (4) and at least a side (14)

d) Forming of at least a collar (22) .

2. A method of making a package according to claim 1, characterized in that the forming of at least a collar

(22) comprises rolling.

3. A method of making a package according to claim 2, characterized in that the forming of at least a collar (22) comprises hot forming of the shape of the collar.

4. A method of making a package according to one or more of claims 1-3, characterized in that the package comprises several parts, including parts having means for closing the package, said parts being preferably made in the same manner as stated in one or more of claims 1-3.

5. A method of making a package according to one or more of claims 1-4, characterized in that the sheet is provided with a print prior to punching.

6. A method of making a package according to one or more of claims 1-5, characterized in that the making comprises hot forming of double-curved edges and/or faces.

7. A method of making a package according to one or more of claims 1-6, characterized in that the at least one side (14) is separated from the at least one bottom (4) at start, and is at least partly folded and joined separately, following which the at least one side (14) and the at least one bottom (4) are joined.

8. A method of making a package according to one or more of claims 1-7, characterized in that punched blanks (10) are stacked on a pallet (24) having a fixture (26) intended for the geometry concerned, and that the package is erected immediately prior to filling.

9. A folded package preferably for nutritious and non- nutritious products, including foods and beverages or the like, said package comprising at least a bottom (4) and at least a side (14) , said package being substantially formed of at least a sheet, characterized in that the sheet comprises at least a layer (3) of plastics to which an amount of inorganic powder material has been added, and that the package is substantially formed by folding and welding, and that the package comprises at least a collar (22) which is suitable for receiving means for closing the package.

10. A folded package according to claim 9, characterized in that the sheet comprises at least a cover layer (5) of plastics.

11. A folded package according to one of claims 9 or 10, characterized in that the sheet is provided with a print which is applied prior to the forming of the package.

12. A folded package according to one or more of claims 9-11, characterized in that the package comprises several parts, including at least a part provided with means for closing the package, said parts being preferably made of the same type of material .

13. A folded package according to one or more of claims 9-12, characterized in that the sheet comprises at least a barrier layer (7) .

14. A folded package according to one or more of claims 9-13, characterized in that the sheet comprises at least a layer of plastics which is foamed.

15. A folded package according to one or more of claims 9-14, characterized in that the collar (22) is intended for snap lids (20) .

16. A folded package according to one or more of claims 9-14, characterized in that the collar (22) is intended for snap-in lids (18) .

17. A folded package according to one or more of claims 9-14, characterized in that the collar (22) is intended for press lids (21) .

18. A folded package according to one or more of claims 9-17, characterized in that the sheet comprises at least a cover layer (5) , which preferably comprises at least an olefin.

19. A folded package according to one or more of claims 9-18, characterized in that the inorganic powder material preferably comprises lime and/or talc.

20. A folded package according to one or more of claims 9-19, characterized in that the at least one layer (3) constitutes at least 75 per cent of the total thickness of the sheet .

21. A folded package according to one or more of claims 9-20, characterized in that the amount of inorganic powder material constitutes at least 20 per cent by weight of the at least one layer (3) .

22. A folded package according to one or more of claims 9-21, characterized in that the amount of inorganic powder material preferably constitutes at least 50 per cent by weight of the at least one layer (3) .