AND METHOD OF MANUFACTURING

FIELD OF THE INVENTION

The present invention relates to packaging for food products, such as crackers, biscuits, cookies, confectionery, chocolate like or other snacks, provided with a resealable opening and preferably a wide opening. More particularly, the invention relates to such packaging comprising:

a flexible container having a top face, a bottom face and side faces,

a container aperture wide enough for withdrawing a food product and having lateral edges extending at least within the top face,

a flexible closure flap extending from a base portion designed to remain bonded to the container to a gripping member, and provided therebetween with a movable portion covered of repositionable adhesive on lateral margins and on a free end margin which are peelable from a closed position in which said movable portion covers the container aperture and said margins adheres to a peripheral area thereof.

BACKGROUND OF THE INVENTION

There is a demand of the consumers for food products packaging having a closure which enables to withdrawn only a portion of the products and to reclose the packaging in order to preserve the freshness of the remaining products during a period which may vary from hours to few days. In particular with dry food products like crackers, the ambient humidity may quickly alter their crispiness.

Packagings having a resealable opening are known notably from the document EP1637472 A1 which discloses a label which can be reset over a slit shaped opening formed by tearing off a portion of the double layer wrapping at the first opening.

However, with that kind of packaging the accessibility to the food products and the tightness of the reclosed packaging are still to be improved, notably when a substantial portion of the food products have been withdrawn.

Indeed, with that packaging comprising a layer of corrugated card wrapping tightly a stack of biscuits, the biscuits remaining at the ends have to be displaced up toward the slit shaped opening. That creates deformations of the packaging and then the closure flap cannot be replaced in a sufficiently tight manner to preserve the freshness.

Moreover, this corrugated layer wrapper is not rigid in radial direction by itselves. If no biscuit remain in the opening region, the wrapper tends to collapse when the user pulls down the closure flap on the wrapper film to adhere the repositionable adhesive. Consequently, it is particularly difficult to obtain a resealing function for food products contained in bulk in such packaging.

SUMMARY OF THE INVENTION

The present invention has for an object to improve such packaging regarding their resealability and the convenience of use. But the needs of the food industry for packaging inexpensive and which generate as less as possible waste must not be overlooked.

With that object, the present invention proposes a resealable packaging for food products of the above-mentioned type, characterized in that the flexible container contains a supporting insert comprising a frame extending along the side faces of the container, said frame having a lower peripheral edge laying against the bottom face at least along foot portions thereof, and having a top peripheral edge situated at the level of the top face at least in head portions between which at least two top panels extend just below the top face, said supporting insert covering at least the inner face of the flexible container in the area on which the lateral margins of the closure flap adheres, so that it supports said flexible container during the resealing of the closure flap.

The supporting insert provides a support within the flexible container which prevents it to collapse when the closure flap is gently pressed on it, notably on the top face. It can be noted that the base portion and the free end margin of the closure flap have not to be necessarily supported by the insert even that is not excluded. In fact, it appears that a support of the area on which lateral margins adhere is essential, and could be sufficient to obtain satisfactory resealing.

The supporting insert also enables to maintain the cross-sectional profile of the flexible container over the longitudinal portions receiving the lateral margins, even the supporting insert has no panel facing the bottom face. This thanks to the frame structure of the supporting insert which must have end walls connecting longitudinal walls, and consequently preventing the longitudinal walls to come closer. That effect would not be obtained with an insert merely made of a corrugated card sheet bend in a U-shaped form. It could be noticed that the frame of the supporting insert has not to wrap tightly the food products, which may even be contained in bulk, so they can move more or less freely toward the container aperture.

It appears that the quantity of material needed for the supporting insert remains acceptable in view of the obtained advantages. Additionally, the manufacturing and the filling process are compatible with existing facilities for packaging food products directly in seam sealed flexible film. In preferred embodiments of the invention, one or many of the following features can be used.

The supporting insert does not extend within the container aperture, this with the aim to prevent adhesion of the margins to the insert.

The top peripheral edge of the frame has lower portions facing the base portion and the free end of the closure flap, said lower portions being situated below the head portions and at a distance of the container aperture. That arrangement enables to save material and appeared not detrimental for the resealability.

Each of the top panels has a free edge extending along a lateral side of the container aperture and at a distance thereof substantially shorter than the width of the lateral margins, in order to support most of the lateral margins width.

The top panels have four sides, three of them being linked to head portions of the frame. This arrangement improves significantly the vertical load which can be supported by the insert.

The lower peripheral free edge of the frame defines the widest inner cross section of said frame, at least for an initial configuration. Thanks to that feature the food products can be inserted through the lower peripheral edge without interfering with the top panels.

The lower peripheral edge of the frame comprises movable portions in addition of the foot portions. Said movable portions enable to closely fit to the shape of the products.

The supporting insert is made of double face corrugated board. Other materials can be used. However a double face corrugated board offers a particularly good compromise between the rigidity to be reached, the quantity of material needed and its price.

The supporting insert is made from a single sheet like insert blank assembled only by mutual engagement of tabs. Such an insert, excluding glue, is advantageous for food products and cheap to manufacture, despite the fact it need more development time before being on production.

The flexible container extends along a longitudinal axis between to opposite side end faces having a sealing seam,

and the closure flap extends in a direction perpendicular with respect to said longitudinal axis, the container aperture having width along the longitudinal axis which is comprised between 60% and 90% of the top face length, and preferably about 70% of said length. These features offer a particularly convenient packaging to the users, together with a good resealability.

The supporting insert contains a stack of flat food products having a longitudinal widest outer section which substantially corresponds to the inner cross section of the lower peripheral edge of the frame, at least for an initial configuration. Consequently there is no particular issue for filling the supporting insert even for stacked food products.

The invention also relates to a method of manufacturing the resealable packaging having any of the above features. The manufacturing method comprises the steps of: providing a flexible film with the closure flap;

- providing the supporting insert;

- filing the supporting insert with the food products through the lower peripheral edge thereof;

folding the flexible film around the filled supporting insert; and then

- sealing the flexible film longitudinally and at cut ends to form the sealed flexible container.

In a preferred embodiment of the method the food products are stacked horizontally on a conveyor, and the supporting insert is move in a transverse direction with respect to the axis of the stack, in order to pass said stack through the lower peripheral edge of the frame.

According another preferred feature of method, the supporting insert is filled in a location which is offset from a transportation path of the flexible film.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages and characteristic features will become apparent from the following description of a preferred embodiment, given by way of example, with reference to the drawings, in which:

figure 1 is a schematic perspective view of a food packaging according to the invention having a closure flap in open position and a supporting insert represented in dashed lines;

figure 2 is an elevation view of the packaging of the figure 1 in which the closure flap is in closed position;

figure 3 is a partial cross-section view along the line Ill-Ill of the figure 2;

figure 4 is a side view of the supporting insert of figure 1 ;

figure 5 is a top view of an insert blank for forming the supporting insert of figure 1 ; and figure 6 is a schematic representation of the manufacturing process of the packaging of figure 1 .

DETAILED DESCRIPTION OF EMBODIMENTS

The same numeral references are used in the figures to designate identical or similar elements.

At figure 1 , is represented a packaging 1 designed to containing food products 3 schematically represented at figure 6.

In this embodiment, the food products are crackers of globally rectangular shape and more precisely octagonal with a shape corresponding to a rectangle with the corners cut off. They are arranged adjacent to each other to form a stack. The food products are not necessarily rectangular, they could be more or less round or polygonal. The packaging is suitable for various kinds of dry food products, like biscuits, cookies, slices of bread. The food products are not necessary arranged to form a stack. The packaging is also suitable for smaller products in bulk, like any kind of snackers or sweets, as it will appear from the description below.

The packaging 1 comprises a container 10 made of flexible film 1 1 so that the container is flexible itself.

In the embodiment container 10 has an elongated shape extending along a longitudinal axis X between two longitudinal ends (10a, 10b). The container 10 presents a top face 12, a bottom face 13, and side faces. In the embodiment, the side faces comprise a front side face 14, a rear side face 15 and two opposite lateral faces 16 at the longitudinal ends (10a, 10b).

The outside of the flexible container 10 is printed with decorative and information graphics, not represented on figures 1 and 2 for sake of clarity.

The flexible container 10 is not however a parallelepiped. The lateral side faces 16 can present a pyramidal shape, like in the preferred embodiment, terminated by transversal sealing seams 17 made by a heat sealing bond. The flexible container 10 does not wrap the stacked foods products in a tight manner. Consequently, the flexible container 10 may not have a cross section profile with accurate angle but a somewhat more rounded profile that the food product. In fact, in the embodiment represented, the flexible container is also named a slug. It has no sharp edges, and somewhat bevelled longitudinal edges. In case of products in bulk, the flexible container may further differ from a parallelepiped. The cross section profile is not necessary a rectangle, but could be any kind of polygon, even a triangle. In that case the top face is particularly narrow and the front and rear faces are not parallel. Anyway, the expression "side faces" must be interpreted as meaning the surfaces of the container 10 visible on an orthogonal side view, the top of bottom faces (12, 13) being the complementary surfaces.

The flexible film 1 1 is made of plastic, in particular made of polypropylene (PP) having a thickness about 40 micrometers in the preferred embodiments. However the film can be made of another material, by way of example made of polyester (PE) and polypropylene (PP) laminate and its thickness can vary substantially depending of the resistance and various properties needed for the food contained. The thickness can notably vary within a range of 30 to 90 micrometers.

To form a tubular body, the flexible film is sealed along a longitudinal sealing seam not visible on figures, which extends through the bottom face 13 up to the end sealing seams 17.

The flexible container 10 has an aperture 19 designed to enable withdrawn of at least one product 2 there through. The container aperture 19 is located on the top face 12. In the preferred embodiment, the aperture 19 extends transversally through the top face 12 and upon an upper portion of the front and rear side faces (14, 15) in order to facilitate the withdrawn of food products.

The aperture 19 as a width w, measured along the longitudinal axis X, which represents a major portion of the top face 12 length I, as best seen on figure 2.

In the embodiment represented, the aperture width w is about 90mm representing about 70% of the length I of the top face 12. The aperture width w could represent a shorter portion of the top face and could be reduced to a slit shaped aperture. However, a wide aperture, representing at least 60% of the top face length I, is much more convenient for the user and enables to use the opened packaging as a tray laying on a table.

The width w can be greater than 70% notably for longer packagings. But preferably no more than 90% of the length I of the top face 12. In fact, as it will appear below, the end portions of the container top face 12 must preferably remain uncut for facilitating the resealing after the first opening.

As it can be seen on figure 1 , the lateral edges of the aperture 19 extending transversally through the top face 12 are rectilinear. The front edge of the aperture 19 extending longitudinally on the front side face 14 is arc shaped.

The aperture 19 is delimited by a continuous cut out line 19a, so that no portion of the flexible container 10 has to be tear off at the first opening of the packaging, at least in the peripheral area of the aperture 19 so that area is not subjected to permanent deformation of the flexible film. However, the cut line can include few indentations defining narrow strips 19b, possibly with an end not cut, which extend toward the aperture centre to form integrity indicating means as described in document EP1975081 A1 . Such narrow strips 19b cannot create significant permanent deformation of the peripheral area.

The packaging 1 further comprises a closure flap 20 provided on the outer side of the flexible container 10. The closure flap 20 comprises a base portion 21 indicated on figure 2, a movable portion 22 designed to cover the container aperture 19 and a peripheral area thereof in closed position, and gripping member 23 at the opposite longitudinal end of the base portion 21 .

The closer flap 20 is considered as extending from the base on portion 21 to the gripping member 23, even if it could have a width w longer than its length, in order to cover the wide aperture 19. The directional axis of extension of the closure flap, indicated by the axis T on figure 2, extends in a transverse direction with respect to the longitudinal axis X. This direction of the closure flap avoids interference with end sealing seams 17 and this is convenient for withdrawing food products.

The closure flap 20 is made of flexible material and preferably made of a plastic film. In the preferred embodiment, the flexible material is a transparent film of PP which has a thickness about 50 micrometers.

The closure flap 20 is covered of a repositionable adhesive, notably a pressure sensitive adhesive (PSA), unless over the tab forming the gripping means 23. The layer of adhesive is uniform and thin like for a label.

The base portion 21 of the flap adheres to the rear side face 15 over a medium portion thereof situated below the end of the aperture 19. The base portion has to remain attached to the flexible container 10, at least during a normal use. With that purpose peeling stop cuts are created through the base portion can be replaced by other means like a layer of permanent adhesive or a hot sealing between the base portion 21 and the flexible container 10.

The movable portion 22 has to be wider than the container aperture 19 in order that two lateral margins 24 and a free end margin 25 covered with the repositionable adhesive, indicated by dots on figure 1 , covers a peripheral area of the aperture 19. The peripheral area can be covered over a portion by the base portion 21 to complete the U-shaped margins (24, 25) of the movable portion 22. However, it is important, at least before the first opening, that the closure flap 20 uniformly and tightly covers the peripheral area of the container aperture 19, since this aperture is delimited by a cut out line through the container 10. By way of example, a margin 24 of 15 mm wide, as indicated by m on figure 2, provides a sufficient sealing.

It is highly preferable that the central area of the movable portion 22, which corresponds in shape and position to the aperture 19 in the closed position, is not adhesive. Many possibilities can prevent the central area to be sticky, like keeping the central area free of adhesive. However, it is more advantageous to cover the central area with a panel 27 cut out from the flexible film 1 1 of the container.

According to the invention, a supporting insert 30 represented in dashed lined at figures 1 and 2, and in a blank configuration at figure 5, is provided.

The supporting insert 30 comprises a frame 40, i.e. a rectangular, or polygonal, member forming a peripheral wall delimitating free passage. The frame 40 extends along the side faces (14, 15, 16) of the container 10, so that it has a rectangular profile visible in dashed lines on figure 2. The frame 40 has a front 44, a rear 45 longitudinal walls linked by end walls 46.

The flexible container 10 can wrap the frame in a tight manner or with a slight clearance. But a loosely fit of the frame 40 within the flexible container 10 is preferably avoided for preventing the frame to move inside the container.

The frame 40 has a peripheral lower edge 47. The lower peripheral edge 47 can be comprised in a single horizontal plane for laying against a bottom face 13 along its whole circumference. However, in the preferred embodiment, the peripheral lower edge presents some portions, called foot portions 47a, situated at a lower level than the remaining portions of that lower edge. The foot portions 47a are situated at the lower edge of the end walls 46 and come in contact with the bottom face 13 of the flexible container as it can be seen on figure 3, when the packaging rest on a table in the configuration on figure 1 . The lower peripheral edge 47 is a free edge, since the supporting insert 30 has no bottom wall.

The lower peripheral edge 47 comprises also longitudinal portions indicated by 47b which correspond to the bottom edge of the longitudinal walls (14, 15).

The frame 40 has a top peripheral edge 48 which corresponds to the highest points of the frame 40. The top peripheral edge 48 comprises head portions at a highest level which are situated just below the top face 12 of the flexible container, possibly in contact with that top face.

More particularly, in the embodiment represented, each longitudinal end of the frame comprises a U-shaped head portions formed by the edge 48a of the end wall 46 and two adjacent short portions (48b, 48c) corresponding to the top edge of the longitudinal walls (14, 15).

The supporting insert 30 further comprises two top panels (51 , 52). Each top panel (51 ; 52) extends between the head portions (48a, 48b and 48c), so that they extend just below of the top face 12 of the flexible container 10.

The top panels (51 , 52) must cover the inner face of flexible container 10 over the area on which the lateral margins 24 of the closure flap 20 adhere when the gripping member 23 is pull down.

The supporting insert 30 supports the flexible container 10 in the area on which the margins (24, 25) have to be gently pressed in order to adhere to the packaging with repositionable adhesive of the movable portion 22.

The supporting insert 30 prevents the formation of wrinkles or waves in the flexible film of the container 10 thanks to the presence of the frame 40 and panels (51 , 52) against the inner face of the flexible film 1 1 . But also by preserving the cross section profile of the flexible container 10 and then avoiding formation loops on its flexible faces.

For supporting the area facing the lateral margins 24, it is possible to provide narrow top panels linked only to opposite head portions, like head portions 48b and 48c of the front and rear side walls (44, 45).

In the preferred embodiment, the top panels (51 , 52) are linked on a third side to the head portion 48a of the end wall 46. That feature increases significantly the capacity of the top panels (51 , 52) to support a load. The fact that the end walls 46 form both the foot portions 47a and the head portions 48a, also improve the capability of the supporting insert 30 to bear a load.

Preferably, the top panels (51 , 52) do not extend within the container aperture 19 in order to prevent adhesion between the margins (24, 25) and the supporting insert 30 which may made of material much more adherent to the repositionable adhesive than the flexible film 1 1 .

In the preferred embodiment, the free edge of the top panel (51 , 52) extends along the corresponding lateral side of the container aperture 19 at distance substantially shorter than the width m of the lateral margins 24.

In this embodiment, the top panels (51 , 52) are designed to have free edge at distance of 2 or 3 mm of the aperture 19 while the margins have a width m about 15 mm.

It can be noticed that the linking of the top panels (51 , 52) along three of their sides, enables to have a slopping panels adjacent to the top portions (48b, 48c) of front on rear longitudinal walls (44, 45), despite the fact that that slopping panels tend by themselves to reduce the capability to support a vertical.

The supporting insert 30 must be inexpensive to manufacture in order to limit the additional costs implied by the resealable opening function of the packaging. It is also preferable that it can be recycled. But the supporting insert must be enough rigid or stiff, to support the load applied by a user to adhere the lateral margins 24 when he pulls down the closure flap 20. A corrugated card material is inexpensive. However, a double face corrugated is highly preferable for withstanding a vertical load. In fact a single face corrugated is too flexible in the direction transverse to the flutes to support any load. More particularly, the corrugated board has an important number of flutes per foot, like the F-flute type, and is relatively thin, with a thickness about 1 .3 mm. Other materials can be used, like card board or synthetic resin. It could be notably preferred to make the supporting insert from cast film, like a cast polypropylene (CPP), in order to reduce the thickness of the walls.

The supporting insert 30 is made from a card or foil material into which a blank 50, represented at figure 5, is cut out. The blank 50 consists in a single piece which is erected by folding and mutual engagement of tabs to form the supporting insert 30, without any further fixation means like glue or staple. More particularly, the end walls 46 are attached to the front and rear longitudinal walls (44, 45) to form a peripheral frame by virtue of tabs (44a, 44b, 45a, 45b) which are inserted through slits 46a of the end walls 46. The tabs are engaged with the end walls 46 by a dent defined by a slit 47 which is passed over the edge of the slit 46a. The folding lines are preformed by dinking the blank 50 along corresponding lines indicated on the figure 5.

The front and rear longitudinal walls have a hinged panel (44d, 45d) adjacent to the lower peripheral edge 47. Then the lower peripheral edge of the frame 40 has movable portions 47b. The movable portions 47b can move from an initial configuration, visible on the right of figure 4, in which they extend in the plane of the longitudinal wall (44, 45), to a packaging configuration visible on the left in which they slop toward the foot portions 47a.

In the initial configuration, the lower peripheral edge 47 defines a widest inner cross section of the frame 40 which enables to pass there through a stack of biscuits. If the stack of biscuits has a rectangular shape with bevelled corners, like in the preferred embodiment, the hinged panels (44d, 45d) enable to surround them in a pretty close manner. Thanks to that feature, the food products shape can be directly recognized from the outside. Various manufacturing process are possible to manufacture and fill a packaging according the invention. However, a preferred method for manufacturing the packaging is schematically represented at figure 6.

The food products 3 are arranged to form horizontal stacks on a chain conveyor 61 . Each stack is maintained between a front stop 63 and a rear stop 64. The front and rear stops (63, 64) have upper ends diverting from the products 3. The front stop 63 is resilient, made of a metal band by way of example, to exert a light pressure on the stack and for enabling some variations of the stack length.

The manufacturing facilities further include an automatic blank erecting machine 66, a flexible film transportation path 67, a flexible film folding device 68, a longitudinal sealing device 70, and a transverse cutting and sealing device 72.

The insert blanks 50 are feed to the erecting machine 66 which set them into the three-dimensional shape of the supporting insert 30. The machine 66 also put an erected supporting insert over each horizontal stack of food products 3 by inserting the end walls 46 between the stack and the stops (63, 64). The lower peripheral edge 47 advantageously defines the wider inner cross section of the frame 40 during this step in order to fill the supporting insert 30 easily. In other words, the insert 30 is in an initial configuration if the frame comprises hinged panels (44d, 45d).

The filling is done by a relative movement of translation between the stack of products 3 and the insert 30 in a direction perpendicular with regard to the stack axis. In the described embodiment, the supporting insert 30 is move downwardly over the stack. Nevertheless, other relative movements are possible.

It should be noted that the supporting insert 30 are filled in a location which is offset from the flexible film transportation path 67, and not above the flexible film as usual for manufacturing seam sealed flexible containers. Thus, the risk that crushes fall on the flexible film 1 1 is limited.

The products 3 surrounded by the supporting insert 30 are pretty well hold together, and may tilted if necessary. The filled supporting inserts 30 are then transported towards the devices (68, 70, 72) enabling the formation of the flexible container 10 enclosing the products 3 and the insert 30. These devices can be quite standard.

The flexible film 1 1 previously printed and provided with closure flaps 20, is transported in a flat configuration to the folding device 68 which bends the film up to obtaining tubular profile around the supporting insert 30. During that step the hinged panels (44d, 45d) are move against the products 3 to follow their outer profile. Then the longitudinal edges of the film 1 1 are welded together by the longitudinal sealing device 70. The next device 72 forms the transverse seams 17 which close the flexible containers 10 and perform a transverse cut to obtain individual packaging.

The detailed description here above is not limitative, various modifications can be adopted in addition to those mentioned above. The possible modifications depend notably on the kind and the shape of the food products to be contained within the packaging.

Any reference sign in the following claims should not be construed as limiting the claim. It will be obvious that the use of the verb "to comprise" and its conjugations does not exclude the presence of any other elements besides those defined in any claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.