GB2326398A - Producing and applying printed packaging wrappers - Google Patents

Abstract

In a method for producing and applying printed packaging wrappers to food containers a reel of flexible wrapping material is printed on both faces with the required designs in longitudinal column form, these being in register. The supplying reel is then divided into smaller individual width reels which may be formed into individual sheet or fan formed feed wrappers. The wrappers are then transferred to the packaging machine where the container is wrapped in a sleeve form with the desired print facing outwards. The sleeve may either be secured by attaching its own transverse free ends together and allowing tension in the material to retain it, or sealed to the peripheral edge of an open container by heat sealing.

Description

Improvements relating to Packaging Sleeves Field of the Invention This invention reiates to printed packaging sleeves or banders, and particularly to the production of such sleeves, e.g. for packaging products for presentation in a store, or supermarket, particularly food items.

.Background to the Invention At present, for food items, such sleeves are conventionally produced in cardboard and the production method includes printing several designs, usually in colour, of a design for one food item to be packaged on one side of a large sheet of carton board, transferring the printed sheet to a cutting and creasing press to indent creases and cut out individual blanks for the sleeves, transferring the sleeve blanks to a gluing machine which folds the blanks along the creases and glues co-operating edges together to produce finished sleeves. Each sleeve is then fitted by hand over the food item and located thereon by press-outs formed in the sleeve.

Such a production method has many disadvantages, as follows: (i) Different designs for more than one food item can be printed on the large sheets of carton boards, but this requires the quantities required for each food item to be of equal ratios, which seldom happens and incurs expensive waste, and the possibility of a wrong sleeve being fitted to a food item.

(ii) Carton board is expensive, and inflexible since it can only be erected/constnrcted in one direction determined by the creasing blades of the cutting and creasing press.

(iii) Production is expensive in machinery terms and labour intensive.

(iv) These sleeves cannot be used to seal the food into the cartons and require that the carton is pre-sealed with polyethylene or other food-compatible film prior to the sleeve being applied. This requires additional time, labour and materials.

It is also known that lightweight, flexible banders can be used to label food products as described in EP 0683100 and EP 0160374. These documents describe various ways of converting a film web, printed on one side, into a bander around a food product. The technology needed to print a plurality of repeating columns across a web of material and to divide these up into rolls by a slitting process is known from US 3,948,504. As with the cardboard sleeves, different language versions can be printed side by side and the roll with the appropriate language version on used at any one time. Once again, this can be wasteful in materials since it assumes that the correct proportion of each language version has been printed. This method cannot allow for changes during the production process other than by wastage.

This technology also requires that the packing house has equipment which is capable of accepting film webs. This requires sophisticated and expensive machinery which is not always available on existing packing lines. Thus, this technology cannot always be adopted simply and easily and without considerable cost outlay.

Whilst the prior art describes various forms of sleeve and bander these are generally applied to a pre-packaged product requiring two packing processes and two ;ots of packaging material.

An object of the invention is to provide an alternative production method which avoids some or all of the above disadvantages and which can be used on existing packing lines with minimum modifications.

Summary of the Invention According to the present invention, in its broadest sense, there is provided a method of producing and applying printed packaging sleeves comprising the steps of: (i) printing a plurality of design sets on both sides of a reel of flexible packaging material, each set comprising the same repeating design extending as a column along the length of the packaging material, the designs on both sides of the packaging material being in register; (ii) cutting through the reel to separate the columns to provide individual design sets in reel form; (iii) further processing the design set reels by sectioning the contents of the reels to give individual packing sleeves in sheet form or folding the material between designs to give a stack of folded sleeves in the form of a fan form feed; (iv) transferring at least some of the sheets or fan form feed to a packaging machine; and (v) wrapping each sheet around a respective container of packed product with the desired printed face outwards to form a sleeve around the container.

In a preferred arrangement the reel of packaging material is printed on both sides, with different language versions of the same design set.

Preferably the packaging material is paper. Paper is significantly cheaper than carton board, easier to manipulate in printing equipment and reels are smaller per unit length of material.

Typically, the sleeve is held in place around the container by frictional forces due to the natural elasticity of the sleeve material. Paper is an ideal substrate for this.

With such an arrangement, it will be appreciated that one reel of paper can provide a number of different design sets, e.g. each set can comprise a picture of one particular food item with information and instructions in a different language, in which case the one reel could be used to pack a large number of the same food items with a range of different languages, depending upon the different countries to be exported to.

In an alternative embodiment contents of the cut reels are folded, the folds being substantially between individual designs to provide a stack of folded sleeves in the form of a fan form feed suitable for feeding into a packing machine.

In the present method of production described above, it will be appreciated that food items are sealed into cartons or other containers prior to being fitted with their sleeves.

A further object of this invention is to provide an alternative method which avoids pre-sealing.

According to a feature of this invention, the packed products are presented at the packing station in unsealed containers and the individual sheets of sealed paper are additionally sealed around the container mouth.

It will be appreciated that the scope of the invention includes the production of paper reels, single sheets, or folded sheets, printed with design sets and sealed with a protective coating for use with the production method, as well as the finished sleeves and packed products with packaging sleeves applied thereto in accordance with the production method.

Description of the Drawings In order that the invention may be readily understood and further features made apparent, embodiments of the production methods in accordance therewith will now be described with reference to the accompanying drawings, in which Figures 1A and 1B show the underside and topside of a reel of paper with a printing arrangement for food items, or other products.

Figure 2 is a schematic view of a sheet feeder feeding a series of sheets to a packing station for sleeving a sealed food tray, and Figure 3 is a view similar to Figure 2 for sleeving an open food tray.

Description of the Preferred Embodiments Referring to Figures 1A and 1B a reel of paper 1 is printed with a number of design sets, each comprising a column 2 defined by the dotted parallel lines 3 of repeating designs 4. In this embodiment the design sets have been arranged for distribution of one particular food item mainly in the UK, with smaller volumes to be exported to five other European countries. Thus, it will be noted that five columns of identical design sets are printed across the width of the reel 1 on the underside thereof, whilst one design set column is provided for each of the European languages on the topside. It will also be noted that the printing of the columns and design sets on respective sides of the reel are in register. It will be appreciated that other design set arrangements can be printed according to requirements, e.g. they can cover a range of different food items with information in the same language; furthermore, the width of each column can be varied according to the width of different sleeves to be produced from the reel.

Following printing, both sides of the paper are provided with a protective coating, e.g. a UV Varnish, or clear PVC, in a manner known per se. Spaces or gaps can be provided in the vamish or other protective coating to allow specific batch information, such as the sell by/use by date to be over-printed on the sleeve at the time of packaging. The reel 1 is then slit along the lines 3 defining the columns 2 and re-reeled into a number of smaller reels 5 (see Figure 1B), each with the particular design set required on a chosen side; in this embodiment on the underside. These smaller reels are then either stored for subsequent use, or fitted onto a cutting or folding machine (not shown) as required.

These smaller reels are further processed in one of two ways. The reels may be cut up into individual banders and boxed or otherwise packaged for later use.

This provides a feedstock for packaging machines which are adapted for sheetfeeding as opposed to being reel fed. An example of such a machine is the LOESCHTM wrapping machine type LCM/gr. This is a fully automatic machine which places a sleeve around boxes, with or without protruding edges, or which wraps them in an overall wrap with end folding. The wrapping material should preferably be heatsealable cellulose film, PVC foil or paper.

The machine delivers a band or sleeve in pre-cut form from a magazine.

Cold glue is applied to the band after it has been drawn from the magazine by a manifold block with a series of nobles mounted on top. The band is pressed on top of the nozzles to deliver a series of dots of glue. When the tray and band are elevated up through the folding box, the under-folder folds the band and supports the tray which, on ejection, comes in contact with the previous folded part of the band.

Referring to Figure 2, the packing machine has a packing station to which sealed, pre-packed food items 6 are fed singly, e.g. by a conveyor belt (not shown) which is fed with banders of a required design set as a series of sheets, typically from a magazine 7. Such food items are typically sealed by a polyethylene or polypropylene film over the top of the food container 6 and heat-sealed around the edge. The end of the sheet 7 is passed around the product 6 at the packing station, trimmed if necessary, and the co-operating edges fixed together e.g. by glue, at the location marked by the arrow 8A. This operation can be completed either by hand or, if the volumes are sufficient, automatically by use of suitably designed guide and timing devices known per se.

Whereas known carton board sleeves are held in place by folding in preformed press-out comer portions, this requires a separate operation after the outer carton has been placed over the product. It has unexpectedly been discovered that by using a paper or plastic sleeve stretched tightly around the product, the natural and intrinsic elasticity in the sleeve material holds the sleeve in place quite satisfactorily. Thus there is no need for further cuts, folds, press-outs or other operations. This results in significant cost savings.

An alternative gluing point is shown as 10 in figures 2 and 3. Where the food containers are relatively flexible the comer of the container tends to be the most rigid region on which to press the edges of the sleeve when gluing. This adaptation allows even relatively thin containers to be banded successfully.

It will be appreciated that food cartons are often wider at their open face than at the base. That is to say, the sides are angled inwards towards the base. Where the sleeve covers the entire open face of the container there will be inevitably be a portion of the sleeve which does not overlap the base. This presents problems when gluing the sleeve ends together because there is no co-operating surface to press the sleeve against. This can be overcome by placing the container between retractable jaws whose faces correspond to the angle and depth of the container sides. With the jaws in contact with the container, the jaws provide a firm surface against which to press the ends of the sleeve during the gluing process.

In an alternative embodiment, the sleeve can be glued to the carton itself at one end, wound around the carton and the other end of the sleeve attached to the first end. This provides a stable sleeve that will not slip around the carton and is also prevented from sliding along its length.

Referring to Figure 3, a second aspect of the invention is particularly applicable to food items in open trays 6 that need to be sealed. The method is basically the same as described above, but includes the further operation of additionally sealing the printed web 7 to the mouth of open trays 6 fed to the packing station. In this case, that part of the sleeve produced extending around the sides and bottom of the tray can be readily tom off, if not required, with the aid of lines 9 of perforations formed during the production of the paper reels and extending across the width of the webs at appropriate, longitudinally spaced, positions.

In this application the face of the sleeve which is in contact with the food is laminated with a food-compatible plastics material such as polyethylene or polypropylene. The region forming the seal is then further coated with a heat sealant such as polyvinyl indene chloride (PVDC). Such heat sealants are known to the materials specialist who would be consulted to determine the optimum laminates, varnishes, sealants etc. for each application.

It has therefore been discovered, for the first time, that a food carton can be sealed and banded in a single operation using sheet or folded stock. This represents considerable savings in packaging, mechanical operations, cost and time. If required, the sealer/bander can also be reversible and printed on both sides as described above to minimise wastage.

It will be appreciated that a range of flexible packaging materials can be used in this method, as selected by the materials specialist. It has been unexpectedly discovered that paper as opposed to carton board is a suitable substrate and this can be sealed or laminated as required. Food-compatible plastics or composite films could also be used and may be more appropriate if the wrapper also acts to seal the mouth of the food tray.

One of the advantages of this method is that paper can be used as the sleeve. This has the advantage that not only is paper cheap compared to other materials but very high quality images can be printed on it cheaply and easily. This contrasts with plastics films where the printing process gives less clear images which are not up to the expectations of the discerning shopper. By laminating after printing the best of both worlds is obtained.

In an alternative embodiment of this second aspect of the invention, the sleeve may be sealed to the mouth of the container, wrapped around the container then glued to its side. That is to say the sleeve need not completely encircle the carton.

In this context the term sleeve therefore encompasses a bander which partly encircles a carton and which is adhered in some way to the carton to keep it in place.

In a further embodiment, the sleeves can be formed separately from the container, around a former for example, and then slipped over the container in a separate operation.

It will be appreciated that a production method in accordance with aspects of this invention has the following benefits, compared with the present method used: (a) Reduced raw material costs i.e. Paper v Carton Board.

(b) Flexibility of varying sizes, design and languages over the reel width particularly where the reel is printed on both sides.

(c) Reduced waste of packaging which in the past was ordered by estimating and guess work, particularly where Foreign language ratios were involved.

(d) If any particular design or Foreign language on one side of the reel is not required, the design on the other side can be used (saving packaging waste).

(e) Stock control is easier and cheaper, which means that write-offs of packaging sleeves are virtually eliminated.

(f) Reduces waste particularly in the trialling of new products.

(g) Enables high quality litho printing to be used.

(h) Provides for coding and pricing in-line by printing- onto pre-determined gaps left on sleeve. Packing then becomes a fully automated process.

(i) No cutting and creasing is required, saving machine and operator costs.

Similarly there is no folding and gluing, other than where the sleeve is formed around the container.

(j) If the reverse side of the sleeve is not required for a second language version, it can be used to provide menu suggestions and recipes.

In summary, using the invention it is possible to use a single sheet to form each sleeve rather than using a reel of packaging material. In this case an automatic machine of known type (for example a LOESCH LCM/gr machine) is used which places a sleeve around the packed product container.

Single sheets of flexible packaging material are pre-printed on both sides and can also be provided with a protective coating e.g. a UV varnish, or clear PVC, in a manner known per se. If the packaging material is to be used in a situation where it will come into contact with food, a food-safe protective coating can be used. During the printing process, different designs can be printed onto each side of the material as described above. For example, different language versions can be provided on each side of a sheet. These single sheets can be formed by cutting lengths from the reels 5 so that each sheet contains a design 4 on each side. The single sheets are then loaded into the magazine or hopper of the packing machine.

The packing machine operates by drawing up a sheet from the magazine to a manifold block. Here cold glue is applied to the sheet from a number of nozzles mounted on top of the manifold block. The sheet is pressed on top f the nozzles to deliver a series of dots of glue to the sheet.

A food tray of other product container is then elevated up through a folding box part of the machine. This folds the sheet and supports the tray. The tray or product container is the ejected from the machine and in so doing comes into contact with the previous folded part of the sheet. In this way the sheet is folded around the tray or container and glued to itself to form a sleeve. By arranging the sheets in the magazine in different ways the required design can be arranged to be uppermost on the packaged product. This reduces wastage of the sheets.

In the case that the product is pre-packaged it is possible for the single sheets to be formed from paper or other flexible packaging material, that has not been pre-coated with a food-safe substance.

It is also possible for material from the reels 5 to be pre-folded in a fan form manner so that individual designs 4 are positioned one above the other. The folded packaging material can then be loaded into a packaging machine of known type and used to form sleeves around the food trays or other packaging containers. Effectively, the machine takes a fan-fonm feed of packaging material rather than single sheets or a continuous reel.

Claims (13)

1. A method of producing and applying printed packaging sleeves comprising the steps of: (i) printing a plurality of design sets on both sides of a reel of flexible packaging material, each set comprising the same repeating design extending as a column along the length of the packaging material, the designs on both sides of the packaging material being in register; (ii) cutting through the reel to separate the columns to provide individual design sets in reel form; (iii) further processing the design set reels by sectioning the contents of the reels to give individual packing sleeves in sheet form or folding the material to give a stack of folded sleeves in the form of a fan form feed; (iv) transferring at least some of the sheets or fan form feed to a packaging machine; and (v) wrapping each sheet or fan form sleeve around a respective container of packed product with the desired printed face outwards to form a sleeve around the container.

2. A method as claimed in claim 1 wherein the reels are sectioned or folded between designs such that each individual sheet or folded sleeve has a single design printed on each side.

3. A method as claimed in any preceding claim wherein the reel of packaging material is printed on both sides with different language versions of the same design set.

4. A method as claimed in any preceding claim wherein the packaging material is paper.

5. A method as claimed in any preceding claim wherein the sleeve is held in place around the container by frictional forces due to the natural elasticity of the sleeve material.

6. A method as claimed in any preceding claim wherein said step (v) of wrapping each sheet or fan form sleeve around a respective container of packed product further comprises fixing an edge of the sheet or fan form sleeve to the cooperating edge of the sheet or fan form sleeve, whilst the packaging material is under tension.

7. A method of producing and applying printed packaging sleeves to pre-sealed containers substantially as herein described with reference to and as illustrated in any combination of the accompanying drawings.

8. A method according to any preceding claim in which packed products are presented at a packaging station in unsealed containers which further comprises the steps of: (vi) sealing at least one side of the packaging material with a protective laminate coating of food-compatible plastics material such as polyethylene or polypropylene; (vii) applying a heat sealing material such as polyvinyl indene chloride to the portion of the packaging material intended to come into contact with the mouth of the container; (viii) winding the individual packaging sleeve around the container and heat sealing the sleeve to the container mouth.

9. A method of producing and applying printed packaging sleeves to unsealed containers substantially as herein described with reference to and as illustrated in any combination of the accompanying drawings.

10. A packaging sleeve formed according to any of the preceding claims.

11. A fan form feed formed according to any of the preceding claims.

12. A packaging sleeve substantially as herein described, with reference to and as illustrated in any combination of the accompanying drawings.

13. A fan form feed substantially as herein described with reference to and as illustrated in any combination of the accompanying drawings.