BG64000B1 - Wrapping packaging - Google Patents

Abstract

The packaging comprises a foil band which can be cut in individual sheets (20, 56, 62), suitable of closing by folding them around the article 34) liable for wrapping, in particular foodstuffs. The band includes, in each sheet (56, 62) along the length of each of its lateral edge, a strip of cold adhesive coating (28, 58, 64 and 66). Strip (28, 66) of one of the lateral edges is on the face side of the band, and strip (58 and 64) of the other lateral edge is on the reverse side of the band, so that strips (28, 58, 64 and 66), by mutual overlapping, hold the wrapping finally closed at the last series of folding. The mutual gluing of strips (28, 58, 64 and 66) is controllable and is sufficiently strong to keep the wrapping closed, but is insufficiently strong to terminate the unwinding of the band from its roller when in wound condition the roller has mutual contact between strip (28, 66) on the face side and strip (58, 64) on the reverse side of the band. 4 claims, 11 figures

Description

Technical field

The invention relates to a wrapping package which is ribbon-shaped and can be cut into separate sheets, suitable to be closed by folding around the article to be wrapped.

Without limitation, the invention is particularly applicable to the field of packaging of confectionery and chocolate or other consumer goods, such as cubes.

BACKGROUND OF THE INVENTION

Generally, the articles are individually packaged in a rectangular sheet of pre-printed (printed) foil tape of suitable size and shape, after which the individually packaged articles can be packed in bulk in a suitable size packaging bag. According to one known method of packaging, the article to be packaged, which, for example, is in parallel epipedic form, is placed in the center of the opposite side, i.e. the non-printed side of a rectangular sheet. The two longitudinal sides of the sheet then turn up (or down, depending on the orientation of the article and the type of packaging machine), vertically toward the longitudinal front faces of the article. The lateral sides of the sheet are then turned upwards, vertically to the two transverse fronts of the article and their upper edges are folded flat above the upper front side of the article, these last two operations being made necessarily by successive and oblique folding operations with the longitudinal sides, already facing up. The packaging is completed by folding the upper edges (which in the meantime have become trapezoidal stripes or ears) on the longitudinal sides, one on top of the other, on the upper front of the article.

It should be noted that, depending on the shape of the article to be packaged and the type of packaging machine, other series of folding of the packing list are possible, these folding series being made in a specific configuration of folding lines. This configuration of folding lines on the packing list always remains the same for the identical item to be packaged using the same packing method.

A significant problem that arises here is the problem of retaining the folds at the end of the packaging operation so that the packaging remains closed. This retention can only be secured at the expense of the special choice of a strip used as a substrate (substrate), which must have suitable mechanical properties, such as flexibility, in particular a pronounced tendency not to return to its original position after the sheet is was folded during packing.

This is a problem, especially when packing small-sized items, such as confectionery, such as candy, pralines, tabs, a non-chocolate bar, chocolate-covered blocks, and other or broth cubes.

One known solution is to select special high-flexibility substrates such as wax paper, cellophane, aluminum laminates, or alternative synthetic tapes containing an appropriate amount of additives that increase the flexibility of that substrate.

However, this solution significantly limits the choice of tapes used as substrates for packaging or significantly increases their cost.

Sheets for wrapping certain articles are also known, such as broths of cubes, in which sheaths are closed by binding. For this purpose, the sheets include on their front (straight) side, which means the outside side of the article to be packaged, a hot-glue structure whose configuration is adapted to meet the configuration of the folds made during the wrapping.

The disadvantage of this packaging process is that the packaging machine must be specifically adapted for this process as a heat source is required. In addition, when this heat source includes heating plates, bonding can only be achieved on a perfectly flat surface of the article to be packaged, and in addition to the time required to make the adhesive seam, a relatively high pressure is required, which a number of products are unable to withstand.

Another disadvantage is that this packaging process is completely unsuitable for the packaging of heat-sensitive articles, in particular chocolate products, and does not allow the choice of a low-temperature-resistant packaging substrate.

Therefore, when creating this type of wrapping wrapper, the purpose is to provide adhesive portions on the belt to retain the folds and, on the other, to keep the tape in a rolled state. As already described here, the problem is, in fact, that if the tape includes self-adhesive portions of the reverse and straight (front) sides, then when the tape is wound on a roll, some of these adhesive portions of two adjacent turns create the risk of overlapping on the pulley and mutual adhesion, which would prevent the belt from developing from the pulley.

EP-0 870 695 describes a packing sheet sealed by folding around the article, the right side (i.e., the front side which will be outside of the article) to which contains a cold adhesive coating structure that is arranged in such a configuration that The adhesive-coated areas overlap as the sheet folds around the article. These adhesive-coated portions thus fix the bends when the sheet material has the exact property of being unable to hold the bends. However, this sheet has on its reverse side a thermally bonding lacquer that keeps the sheet closed.

EP-0 870 695 provides for sections of cold-adhesive coatings only on the straight (front) side. Therefore, there is no risk of overlapping during winding. In order to be able to solve the problem of retaining folds, it is provided on the reverse side connecting the hot lacquer, which leads to the mentioned disadvantages. The sheet also has the disadvantage that the reverse side must have adhesive strips to allow the tape to unroll from the roll.

EP-0 225 987 describes a packing tape which has, on its right (front) and reverse sides, sections covered with cold-adhesive coatings, in particular two longitudinal stripes, one on the right side and one on the reverse country. In order for the tape to be stored as a roll, these different adhesive regions must be arranged in such a way that they are not coiled, since such application would cause these different regions to adhere to one another and stop the tape from collapsing. develops from the roll.

The intended special arrangement of the cold-adhesive coatings on the reverse side, with respect to the straight (front) side or vice versa, so that during the winding the coatings of two adjacent turns are adjacent to one another and do not overlap, in fact dictates restrictions on the the packing process to the extent that the configuration of the folds must be designed according to the location of the adhesive sections, when what is desired is the opposite.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a wrapping package which allows the choice of the tape to be used to be substantially expanded and which allows the tape to be stored on a roll without any overlaps as far as the method of packaging is concerned.

The task is to be solved by a wrapper for wrapping an article, in particular a food product, which is obtained from a tape which can be stored by longitudinally wound on a roll and which can be cut into separate sheets to be subjected of closure by folding around the article. The strip includes on each sheet along its transverse edge a strip of cold-adhesive coating, one of the stripes being on the straight (front) side and the other strip on the opposite side of the strip. Said strips by interlayer and adhesive retain the package finally closed on the last folding series. According to the invention, the interlinking of the stripes is a manageable adhesive that is strong enough to keep the package closed, but not strong enough to interrupt the unrolling of the webbing by its roll when there is mutual contact between the webbing in the roll of the roll. (front) side and strip on the reverse side of the strap.

In a preferred embodiment of the package according to the invention, the straight (front) side of each sheet includes cold-adhesive coated portions extending at least partially along three sides of the periphery of the sheet in such a configuration that most of these coated with cold-adhesive material, portions are applied when the sheet is folded around the article, adhering to each other and holding the folds around the article.

Preferably, the adhesive coating of the stripes on the back of the strip is applied in the form of an oval strip.

It is also preferred that each sheet contains a non-adhesive coating on the entire straight (front) face that is applied prior to the adhesive coating of the sections covered with cold-adhesive material.

It is an advantage of the invention that the presence of at least a partial pre-coating of the tape used as a wrapping wrapper with a specified cold-adhesive coating enables as soon as the packing sheet is closed by folding to achieve folding which can be very well fixed, and also allows the tape to be stored on a roll.

In fact, the substance used as a cold-adhesive coating does not adhere or adhere slightly to a smooth surface or to a surface treated for this purpose, but in contrast it shows good adhesion when applied to itself, which actually occurs during of folding. In addition, the folds are simply fixed by applying a slight pressure and by overlapping some sections of adhesive-coated material, and this can be achieved without other devices other than those necessary for folding the shell.

According to the invention, the term "cold bonding" means bonding which occurs immediately by ordinary contact at a temperature between about 0 and 50 ° C. In fact, temperature is not a critical parameter for achieving adhesion through cold-adhesive coating and has virtually no effect on the quality of the adhesive obtained. In addition, adhesion can be achieved without the need for additional heat to be applied at ambient temperature at the location of the packing unit.

In fact, cold-adhesive coatings have been used so far primarily in layers on a substrate that has little or no deformation. This means that significant blocking problems can be expected due to the self-adhesive properties of the cold-adhesive coating when applied on a rough substrate.

Therefore, it is an advantage of the invention that it allows the use of tapes that are less expensive and exhibit better properties (rigidity, printing capability, aesthetic appearance) for packing articles, without limitation on article form. .

With regard to the use of rigid tapes, it should be noted that so far their use has been avoided for packaging which must be sealed by folding. This is because the rigid bands have a very low ability to hold the fold.

With respect to the problem of storing the roller belt, in comparison with the solutions described in the two documents illustrating the state of the art, the invention provides a completely different solution, which has seemed impossible so far and which consists in allowing the overlapping of some adhesive sections when the tape is stored on a roll. This is possible because the invention provides for the application of a specific cold-adhesive coating which has, as defined in the application, "controlled adhesive", which means adhesive that is strong enough to meet the requirements but not sufficiently strong to to resist repeated peeling. In this way, the tape can be unscrewed several times from the storage roll without undue resistance, even in the case of the innermost turns where the adhesion is normally larger. This solution has significant advantages over the solutions proposed by the said documents, insofar as the same adhesives (and therefore not hot-adhesive) can be provided anywhere and that adhesive sections can be provided in the desired places, in accordance with the shape of the product to be packs, and a series of folds.

The configuration of the adhesive-coated strip structure may take different forms depending on the article to be packed and depending on the folding series.

According to one aspect of the invention, the adhesion achieved by the interlayer of cold-adhesive strips is not irreversible, as it must allow the tape to be unwound without the risk of tearing the tape when this tape is wound and stored on a roll . Alternatively, an adhesive coating should be selected that is appropriate to the type (nature) of the substrate to which it is applied so that, on the one hand, the adhesive coating is sufficiently weak to allow the packing tape to be developed by the roll and, on the other hand, firm enough to allow the package to be sealed almost hermetically. It should be noted here that controlled adhesive also has the advantage that the packaging can be opened and closed several times without noticeably reducing the quality of the adhesive.

One advantage of the invention is that it permits the use of a wide range of options regarding the type of substrate used.

Explanation of the annexed figures

The invention is explained in more detail by way of the exemplary embodiments given below by way of illustration with reference to the accompanying drawings, of which:

Figure 1 represents the straight (front) side of a packing sheet according to one embodiment of the invention;

FIGS. 2-8 are successive batches of one example of candy wrapping using a sheet made according to FIG. 1;

FIG. 9 is a front view of the embodiment of FIG. 1, supplemented by an adhesive structure on the reverse side;

10 is an enlarged sectional view of an embodiment of FIG. 9;

11 is a simplified alternative embodiment of FIG. 9.

Examples of carrying out the invention

Figure 1 shows the straight or printed side of the wrapping sheet 20 after the sheet is cut off by a strip developed by a storage roll (not shown) in the direction shown by arrow A in the figure.

The cold-adhesive coating is applied to a structure 22 which is adapted to fit the configuration of fold lines made during packaging, an example of which will be described below. In the case of FIG. 1 has two structures of strips 24, 26 with a thickness of about 4 mm, approximately W-shaped, along two opposite sides of sheet 20 and lane 28 along a third side of sheet 20, between the two side W- figurative structures. On the opposite side of the side with lane 28 there are also in the corners area two sections with cold-adhesive coating 30 and 32. Compared to the original strip stored on a roll, the strips 24, 26 are along the longitudinal edges, while the lane 28 is transverse. On the roll, these different stripes of adhesive coating of the straight (front) side are on the outside of the different roll turns.

The sheet 20 of FIG. 1 can be prepared by applying on the straight (front) side of a 25 µm oriented polypropylene strip, which may or may not be metallized, a thin printed layer or primer (for example, product 10-612205-4 MX41 of the company SIEGWERCK) designed to improve the adhesion of printing ink. The tape is then printed using known techniques, for example heliographic or flexographic (aniline) printing or alternatively offset printing. A protective lacquer, known in itself, is applied to the printed layer. The cold-adhesive coating structure 22 is then applied to this lacquer according to the pattern shown in FIG. 1. This pattern may also be made using known printing techniques.

The cold adhesive coating can be the product IP7905 or IP7936 of SWALE, which will be embedded, for example in quantities of 3 g / m ¹ . It is an adhesive coating that adheres only to itself. In other words, this coating does not stick to the raw smooth side of the back of the web, which allows the tape to be stored and packaged easily as a roll without any hassle of unwinding. This adhesive coating also has the quality of having a low coefficient of friction on the metal of the order of 0.2-0.6, while the coefficient of friction on the metal is usually 1-1.5. This low coefficient of friction reduces the risk of holding and sticking to the folding block.

A candy wrapping operation 34 of approximately parallelepiped shape, sheet 20 of FIG. 1, with reference to FIG. 2-8. The sheet 20 is placed on the candy (sweets), with the back or the crude side facing the candy (sweets), so that the strip 28 and the opposite side with the adhesive sections 30 and 32 are in the longitudinal direction of the candy (sweets) and the W-shaped structures are in the transverse direction of the candy (sweets). Then the sides of the sheet 20 are folded down on the longitudinal front sides of the candy (sweets), as shown in FIG. 2.

The following operation consists in folding the central portion on each side of the sheet with the structures 24 and 26 on the lateral front sides of the candy 34, as shown in FIG. 3. This operation is performed by folding the longitudinal sides of the sheet 20 along inclined fold lines 36 and 38. As can be seen in FIG. 3, the two W-shaped structures 24 and 26 (26 not visible in FIG. 3) of the adhesive coating are arranged so that the two outer branches of the W-shaped structures extend along fold lines 36, 38 and V - the shaped inner part is facing the transverse side of the candy (sweets) 34.

The next operation consists in folding down on each side of the candy (sweets) 34 the two ears defined by the fold lines 36 and 38 towards the interior in the direction of the arrows 1 and 2 in FIG. 3. This operation places the outer stripes of the W-shaped structures of the adhesive coating, i.e. the strips that extend along the fold lines 36 and 38 above the inner V stripes and terminate in the configuration of FIG. 4. These bending series are clearly the same on both sides of the candy. In such a way that all the stripes of the two W-shaped structures 24 and 26 are fully coated and the cold-adhesive coating used adheres only to itself, the configuration of FIG. 4 is a stable configuration that completely fixes the folds made so far.

The next folding series is shown in FIG. 5 and consists in folding the lower portions of the previously folded and folded down ears on the underside of the candy (sweets) 34. This operation is performed by folding the longitudinal sides along the inclined fold lines 40, 42, 44, 46, which transform the longitudinal sides into trapezoidal shaped ears 48, 50. The result of this folding series is shown in FIG. 6, which depicts a bottom view and a front, which is hidden in the previous figures.

It should also be noted that the two sections of cold-adhesive coatings 30 and 32 are arranged in such a way that their inner sloping edges (see also Fig. 1) extend along the fold lines 40 and 42 of the ears 48, as can be seen in FIG. 6.

Figures 7 and 8 illustrate the last stages of packaging. First of all, the ear 50, which has a strip of adhesive coating 28, is folded down to the inner front, as shown in FIG. 7. The second ear 48 is then folded down to the ear 50 to form the configuration of FIG. 8.

When the ear 48 is folded down, the two adhesive coated portions 30 and 32 are partially overlapped and partly applied to the adhesive strip 28 of the ear 50. As the ear 48 adheres to itself and to the ear 50, the configuration of FIG. 8 is a stable configuration in which all folds are fixed.

It should be noted that when the ear 48 is folded down to the ear 50, the adhesive strip 28 adheres to the adhesive sections 30 and 32 only through its edges. In contrast, its central portion will come in contact with the back of the ear 48, to which it will not adhere. In other words, although the leaf of FIG. 1 produces a package that is stable and long-lasting; it does not provide hermetic sealing.

All series of wrapping phases described below are executed automatically in a packaging machine. In this context, it is important to note that the proposed wrapping sheets are suitable for known packing machines without any need for modification or adaptation. However, it should be noted that the shell (packaging) described below is just one example of a machine's folding configuration. Other machines may perform folding operations along different configurations of folding lines. In this case, the pattern of adhesive structures shown in FIG. 1, it is necessary to adjust to fit the configuration of folding lines carried out by the bending machine, the opposite being more difficult.

In FIG. 9 depicts a preferred embodiment of a wrapping sheet according to the invention, generally referred to as heading 56.

A sheet of oriented polypropylene, suitably printed, preferably after priming, may be reused. Then a non-stick coating 60 is applied over the entire straight (front) side. Suitable non-stick products consist of mixtures of polyamide resin and polyethylene paraffin (for example SIEGWERCK products 10-609345-3P and 994404-X from SICPA) embedded in amounts of 1.5 g / m ² . Next, non-stick coating was applied with cold-adhesive coating specimens 22 identical to those of FIG. 1. A dry-adhesive strip of dry type is then applied to the reverse side, more or less between sections 30 and 32 on the right side, which is represented by a dashed line and indicated by 58. When sheet 56 is applied for the packaging described with reference to FIG. 2-8, the adhesive strip 58 will be at the end of the packaging operation (see Fig. 7) on the inside of the ear 48 and when that ear is folded further, it will adhere to the adhesive strip 28 of the ear 50 to form a virtually airtight container .

When the strip of FIG. 9 is stored in roll form, the adhesive strips 58 on the reverse side are generally in contact with the non-stick coating 60 of the straight (front) side, to which these strips 58 do not adhere. However, when the winding progresses and after a number of turns, the stripes 58 will also come in contact with the adhesive stripes 28. By selecting the type of adhesive of the stripes 28 and 58 and their controlled adhesion, it is also possible to peel off and unroll the tape from the roll without moving the strip and without significantly reducing the adhesive properties of the stripes 28 and 58.

Instead of providing strips of adhesive coating having a substantially rectangular shape, as shown in the figures, it is possible to provide oval stripes. This allows for a gradual detachment, with a lower risk of tearing when the package is opened or when the tape unrolls from the roll.

Figure 10 is a cross-sectional view, enlarged, through the thickness of a sheet made according to an exemplary embodiment of FIG. 9. The various layers denoted by A-F include in this preferred embodiment the following, A is the right side and F is the reverse side:

A - latex-based adhesive coating used in quantities of 2-4 g / m ² , product IP 7985 by SWALE;

B - PVB (polyvinylbutynyl) lacquer, product WO 48825 from SWALE with paraffin additives and non-sticking properties for the coating of layer F, applied in amounts of 0.7-1.3 g / m ² ;

C - color printing with PVB ink, Dynavin series, by SWALE and applied in an amount of 2-3 g / m ² ;

D - water primer, type 200970 by SWALE, applied in quantities of 0.4-0.8 g / m ² ;

E - co-extruded film of oriented BEZ type polypropylene, supplied by VIBAK, 30 μm thick and composed of: E1: metallized layer, 0.2-0.4 μm thick, E2: co-extruded film 1 thick , 5 μ, consisting of a mixture of copolymers and homopolymers, E3: homopolymer core 27 μm thick, E4: homopolymer co-extruded layer with adhesive properties for layer A;

F - latex-based cold-adhesive coating applied in the amount of 2-4 g / m ² , product IP 7983 by SWALE.

The tape produced in this way can be unwound and rolled up to 10 times without losing the adhesive properties required to form a sealed package.

In FIG. lie a simplified alternative embodiment of FIG. 9. In this alternative embodiment, the sheet 62 simply comprises on the reverse side along the length of one of the edges (transverse edge to the strip on the roll before cutting), a strip 64 of cold-adhesive coating corresponding to the strip 58 of FIG. 9 and along the opposite edge, on the straight (front) side, another strip 66 of cold-adhesive material, corresponds to the strip 28 of FIG. 9. The design of the strip may be as described above with reference to FIG. 10. The two strips 64 and 66 are shown in the figures and, as noted earlier, are oval (ovate) in order to facilitate detachment when unrolled from the roll.

In other words, in this alternative embodiment of FIG. 9 shows the structure of the adhesive coating 24, 26, 39, 32 of FIG. 9 not used. This alternative form can be used when practically no hermetic sealing is required, such as is permitted by the embodiment of FIG. 9 and when the closure along the fold lines is not sealed. In contrast, the last packing phase, consisting in the overlay of the adhesive-coated sections 64 and 66, allows the folds made earlier to be held in place when the packing is performed in a machine with a bending (folding) chamber, t .f. when all the folds referred to in connection with FIG. 3-6, are performed simultaneously.

As has been explained, one of the advantages of the invention is that it allows the use of a wide range of options regarding the type of substrate used. Examples of suitable substrates are plastic tapes, about 10 to 100 μm thick, made of extruded and oriented polypropylene, of polypropylene in the form of a cast film, of polyester, of polyethylene, of extruded and oriented polyamide or of polyamide in the form of cast film (tape).

It is also possible to use a paper substrate (glossy or lined). Any padding material or flexible sheathing material may be suitable as a substrate according to the invention. These various substrates may consist of a single layer, a metallized single layer, or several laminated and / or co-extruded layers.

As a general rule, pressure sensitive adhesives are compositions based on natural and / or synthetic rubber (elastomer) coupled with modified cellophanes, phenol-formaldehyde resins or hydrocarbon resins (paraffins). In addition to elastomers, widespread application of styrene, (meth) acrylic acid or vinyl ether based polymers can be carried out alone or in combination and also in combination with resins. It is also possible to apply silicone resins. Preferably, compositions containing mixtures of natural or synthetic elastomers and copolymers of (meth) acrylic acid and styrene are administered.

According to the invention, cold-adhesive coatings are applied to the substrate in an amount of 1 to 5 g / m ² approximately.

Cold-adhesive coatings can be applied as a solution, dispersed or even in a melted state.

Claims (4)

Claims 1. A wrapping package for packing an article (34), in particular a foodstuff, which is a packaging obtained from a strip that can be stored by longitudinally wound on a roll and which can be cut into separate sheets (56) , 62) to be closed by folding around the article (34), the strip including on each sheet (56, 62), along its transverse edge, a strip of cold-adhesive coating (28, 58, 64, 66) , with the strip (28, 66) on one transverse edge being on the straight (front) side of the strip and the strip (58, 64) the other transverse edge is on the opposite side of the strip, such that the stripes (28, 58, 64, 66) retain, by mutual overlapping and gluing, the package finally closed on the last series of folding, characterized in that the stripes ( 28, 58, 64, 66) is a manageable adhesive that is sufficiently strong to keep the package closed, but not sufficiently strong to disconnect the webbing from its roll when there is mutual contact between the stripes in a rolled up condition of the roll. (28, 66) of the straight (front) side and strip (58, 64) on the reverse side of the strap. Packaging according to claim 1, characterized in that the straight (front) side of each sheet includes cold-adhesive sections (22), at least partly along three sides of the sheet periphery (56). a configuration in which most of these cold-adhesive regions are overlaid when the sheet is folded around the article, adhering to each other and holding the folds around the article. Packaging according to any one of claims 1 and 2, characterized in that the adhesive coating of the stripes (58, 64) on the back of the strip is applied in the form of an oval strip. Packaging according to any one of Claims 1 to 3, characterized in that each sheet (56, 62) covers the entire straight (front) side of the non-stick coating (60) applied before the adhesive coating of the coated ones. with cold-adhesive material sections. Attachment: 11 figures Publication of the Patent Office of the Republic of Bulgaria 1113 Sofia, Dr. Γ Blvd. M. Dimitrov 52-B Expert: R. Ashikyan Editor: A. Semerdzhieva Cf. № 41991 Circulation: 40 VC