EP1458627A2

EP1458627A2 - Package, such as a bag, with oriented tear-opening

Info

Publication number: EP1458627A2
Application number: EP02801072A
Authority: EP
Inventors: Jean-Claude Jammet; Stéphane MATHIEU
Original assignee: Soplaril SA
Current assignee: Amcor Flexibles Food France SAS
Priority date: 2001-11-28
Filing date: 2002-11-20
Publication date: 2004-09-22
Anticipated expiration: 2022-11-20
Also published as: AU2002364791A1; EP1458627B1; FR2832698B1; WO2003045816A2; ES2286329T3; WO2003045816A3; DE60219688T2; WO2003045816A8; US20050031232A1; FR2832698A1; ATE359972T1; DE60219688D1

Abstract

Product package, typically a sachet (1) with two side walls (2), a base (17) and an opening (13) through which it is filled before sealing, is made from a material such as a plastic that can be torn manually and has a notch (4) at the end of its tear line. Each of the sachet's two side walls has at least one reinforcing element (50) along the tear line, designed so that the force required to extend the tear line is less than that needed to tear the adjacent barrier. The notch (4) is located in the upper portion of the sachet, typically at a distance of less than 10 mm from the reinforcing element, and the side walls also have guides (61) that prevent the tear from going more than 20 mm from the line of the reinforcing element.

Description

PACKAGING, TYPICALLY A BAG, WITH ORIENTED TEAR OPENING

FIELD OF THE INVENTION

The invention relates to the field of flexible packaging, typically sachets. These sachets are formed from single or multi-layer strip materials, comprising wholly or in part plastic films. It relates more particularly to the opening of the sachets, in the case where the opening comprises the tearing of the strip material forming the sachet, the strip material constituting the sachet being chosen from manually tearable materials.

STATE OF THE ART

Commercial bags are already known which are formed from plastic films which can be torn off manually when they are first opened.

Generally, such bags have, typically at their upper part, an opening zone comprising a tear primer or notch, typically in a "V" shape, so as to concentrate the tear energy at a localized point and thus initiate the tear of the material forming the sachet, and this with minimal manual effort.

Indeed, the opening of the sachet requires in practice the use of a tear primer, such sachets being most often if not impossible, at least very difficult to open when a manual effort is exerted outside the tear primer , which is a guarantee of the integrity of the sachet throughout its lifetime.

In the case of easily tearable materials, there is also known an opening means commonly designated by the name "Tircell" ® typically consisting of a strip with mechanical characteristics superior to those of the material to be torn, attached to the material to be torn, and comprising a free end allowing manual pulling on the strip and thus tearing said material.

Pre-incision techniques are also known which tend to locally weaken a material, for example by laser, so as to facilitate the opening or tearing of a plastic film.

PROBLEMS POSED

On the one hand, in the case of sachets opening by tearing from a primer, it is observed that the tear has a character which is most often random. In addition, the tear can propagate in a certain direction on one of the faces or walls of the bag, while it propagates in a completely different direction on the other face or facing panel.

All this is very annoying since random propagation of the sachet can thus lead to outright destruction of the sachet.

Furthermore, in bag applications, there is no known tearable material which is economical and whose tear could propagate in a predetermined manner or along a straight line.

On the other hand, as the materials constituting the sachets have increasing mechanical characteristics, an opening means of the "Tircell" ® type would not be suitable, without taking into account its relatively high production cost. In addition, certain current sachets which can be sterilized, this opening means, positioned outside the film to be torn, would not be suitable for thermal treatments such as sterilization.

In addition, the presence of a free end on the one hand constitutes a much greater risk of inadvertent opening than the presence of a tear initiator, and on the other hand requires specific and therefore expensive manufacturing means. With regard to the formation of pre-incised lines, they are known on the one hand ^• to require expensive equipment, on the other hand, to be difficult to implement insofar as great precision and regularity of the depth incision is required, and finally, to mechanically weaken the material over a large width, which can be detrimental to the maintenance of the integrity of the packaging throughout its life.

The Applicant has therefore sought a more efficient, reliable and high industrial productivity means for solving the problems posed by the state of the art, and in particular by the use of the laser.

DESCRIPTION OF THE INVENTION

According to the invention, the packaging of a product, typically in the form of a sachet, forms a container comprising two side walls, a bottom and a filling opening, capable of being closed after packaging of the product in said packaging, said container being formed from a manually tearable material, typically in a plastic strip, and comprising a first opening zone provided with a tearing primer typically formed on an edge of said container for the first opening of said packaging a once filled and sealed, said border being typically formed by sealing the edges of the two side walls. This packaging is characterized in that, in said zone of first opening: a) each side wall comprises, typically facing and in parallel, at least one first stiffening element locally reinforcing said side wall and constituting, with said associated side wall, a main barrier to said typically continuous tear, said stiffening element being chosen so that the propagation energy of said tear is less than the breaking energy of said main barrier, so that said main barrier constitutes a partition line of said packaging, with an upper part intended to be torn, in whole or in part, during said first opening, and a lower part intended to serve as a container for said product, b) said tear leader is located, in whole or in part, in said upper part and at a distance from said first stiffening element typically less than 10 mm, c) each side wall comprises means for guiding said tear during said first opening, so that said tear can only deviate from said first stiffening element by at most 20 mm.

This combination of means a) to c) makes it possible to solve all the problems posed by the state of the art.

Indeed, the Applicant has observed on the one hand that the presence of a first stiffening element could in a way form a barrier delimiting two zones (the so-called upper part and the so-called lower part), in such a way that an initiated tear in one zone was not propagated in the other zone, and that by choosing for the stiffening element mechanical characteristics, in particular a resistance to tearing, superior to those of the material forming the packaging. Thus, the tear being typically initiated in the upper part, as opposed to the lower part corresponding to the part of the packaging containing the packaged product, this means makes it possible to guarantee the integrity of the lower part, so that the risk of seeing the product spread when the sachet is opened is thus eliminated.

On the other hand, the Applicant has observed that it was possible to limit the hazards encountered during the opening of a sachet by using in addition a guide means so as to "channel" the tear - tear formed in a way. from a primer close to said first stiffening element in the upper part or at the limit between the upper and lower parts - without it being necessary to assign to the tear a strictly predetermined or precisely determined trajectory, the goal being that the final consumer can open the sachet in a single gesture, without using any accessory, so as to obtain the result simply expected. As will appear in the description of the invention, the combination of means a) to c) can be applied to all types of sachets, including sterilizable sachets, its implementation resulting in either negligible or low additional cost depending on the precise natures of the stiffening element and of the chosen guide means.

DESCRIPTION OF THE FIGURES

Figures la to 15c relate to the invention. Figures la, le, ld, 2a, 2c, 3a, 4a, 6, 9, 10 and 12a are schematic views of rectangular bags (1) with side view of a wall (2) - to illustrate the relative position of said stiffening element (5), of said tearing primer (4), and the presence of said guide means (6).

Figures la, ld, 2a, 3a, 4a and 5 relate to sachets (1) with filling opening (13) unsealed and therefore ready to be filled, while Figures le, 2c, 5 and 6 are relative to bags closed after filling, with sealed filling border (14).

Figures 1b, 2b, 3b, 3c and 4b are sectional side walls (2, 2 ') of the bags (1) at said first stiffening element (5) and possibly said guide means (6).

Figures la to le relate to a first embodiment of the invention in which the stiffening element (5) is a wire (50) and in which said guide means (6) consists of the use of oriented material ( 60) - symbolized by "O =>", and by the sealed border (14).

Figure la represents the bag (1) before filling.

Figure lb is a section along A- A of Figure la.

The figure shows the bag (1) after filling and closing the bag.

Figure 1d, similar to Figure la, shows the bag (1) in which the filling opening (13) is perpendicular to the side (15) of the first opening of the bag. Figures 2a to 2c relate to another embodiment of the invention in which the stiffening element (5) is a wire (50) and in which said guide means (6) is constituted by a wire forming said second stiffening element (61). Figure 2a shows the bag (1) before filling. Figure 2b is a section along AA of Figure la.

Figure 2c shows the bag (1) after filling and closing the bag.

Figures 3a to 3c relate to other methods of the invention.

FIG. 3a represents a bag (1) in which the filling opening (13) corresponds to the entire section of the bag, while said upper part (11) corresponding to the part of the bag torn during its first opening represents only the right corner of the bag.

According to FIG. 3b, the stiffening element (5) and said second stiffening element (61) are formed by localized deposits (53). According to FIG. 3c, the stiffening element (5) and said second stiffening element (61) are formed by extra thicknesses (54) of the material forming the walls (2,2 ′).

Figure 4a is similar to Figure 3a, but the stiffening element (5) and said second stiffening element (61) are formed by a single strip (52) fixed to the surface of each wall (2, 2 ') comprising a central weakening line (520). Figure 4b is a section along A-A of Figure 4a.

FIG. 5 represents a bag (1) in which the stiffening element (5) is formed by a wire (50), and in which said second stiffening element (61) is formed by the sealing edge (14) typically "reinforced "(62) by pleating.

Figure 6 is similar to Figure le, but the wire (50) is oriented with an angle α> 0 relative to the orientation O => of the material forming the walls (2,2 '). FIGS. 7a to 8 schematically illustrate two methods of manufacturing the strip material (7) in the form of a coil (72), intended to form the bags (1) with insertion of the stiffening element (5) and of the guide means ( 6) constituted by a wire (50). According to Figures 7a to 7c, the strip (7) is formed by extrusion or assembly of two layers (70).

FIG. 7a is a perspective view of the strip material (7), the wires (50) being parallel to the machine direction MD of the material. As a simple example, dotted lines (71) diagrammatically cut the walls (2,2 ') in order to form sachets

Figure 7b is a cross-sectional view before the two layers (70) between which the wires (50) are placed, to form a strip material (7), as shown schematically in the sectional view of Figure 7c.

Figure 8 is similar to Figure 7a, but the wire is no longer rectilinear, thanks to a transverse movement of the wire (50) upstream, synchronized with the longitudinal movement in the direction MD.

Figure 9 is similar to Figure le, but the bag (1) is formed by folding along a fold line (16) corresponding to the bottom (17) of the bag.

Figure 10 is similar to Figure le, but the stiffening element (5) consists of a label (51), which can be optionally printed and / or metallic.

Figure 11 shows, in perspective, the bag (1) of Figure 10 after opening and separation of the upper part (11), and manual pressure on the edges (19), so as to elastically separate the two labels (51) and thus release the first opening orifice (15).

FIG. 12a represents a bag (1) in which said stiffening element (1) and said second stiffening element (61) are formed by a label (55), which can optionally be printed and / or metallic, comprising a line of weakness (550) forming said partition line, comprising at its ends the tear caps (4).

FIG. 12b represents a vertical cross section of the sachet according to FIG. 12a, after opening and separation of the upper part (11), and reclosing by using a foldable label (55), typically metallic and printed, for example in aluminum or comprising aluminum.

Unlike FIGS. 7a to 8, FIGS. 12 to 14 are views in longitudinal section in the direction MD, of the formation of the multilayer material (7) in coils (72) by lamination between cylinders of various types of films, the direction MD being generally also the direction of orientation O => of the material if the latter is - oriented, with incorporation between the layers of a wire (50) as a stiffening element (5) and as a second stiffening element (61). FIG. 12 relates to the production of the strip material (7) PET / A1 // PP between the layers of which PA 616 wires are inserted between the layers of PET / Al and PP.

Figure 13 is similar to Figure 12, but relates to the manufacture of the material

PET // A1 / OPP / PP, a nylon thread being inserted between the layers of PET and

Al / OPP / PP. Figure 14 is similar to Figure 3, but the wire is coated with glue (73) before being inserted between the layers of PET and Al / OPP / PP.

Figures 15a to 15c illustrate the manufacture of a strip material (7) in which the stiffening element (5) is a wire (50) arranged in the transverse direction TD, perpendicular to the machine direction MD.

FIG. 15a is a schematic view, in longitudinal section perpendicular to the strip material (7) to be produced, of a device for laminating two films (70) using an adhesive (73), a wire (50) being deposited over the entire width of the strip at regular intervals, so as to obtain a material according to FIG. 15b (top view), then, after removal of the portions of wire external to the material, a material according to FIG. 15c , similar to Figure 15b. Figure 16 shows in section two side walls (2) and (2 ') shown face to face before welding to form a bag, two upper strips (51) forming said guide means (6,61), two lower strips forming said stiffening element (5).

DETAILED DESCRIPTION OF THE INVENTION

According to a first embodiment of the invention, said guide means (6) can be formed by: a) a choice of a strip material (1, 60) oriented in a direction symbolically noted "O = ^: >", l energy of propagation of the tear in said direction being typically at least 1.5 times lower than in a perpendicular direction, b) a relative orientation of said direction "O =>" with respect to the orientation of said partition line formed by said first stiffening element, so that the tear propagates along said partition line of said package, said partition line and said direction forming an angle α formed typically ranging from 0 to 45 °, said package comprising a or two primers (4), themselves possibly forming an acute angle oriented towards said score line.

This modality has been illustrated in Figures la to ld, 6, 9, 10, and 12a.

According to a second embodiment of the invention, said guide means (6) can comprise, on each side wall (2, 2 ′), and typically in parallel, a second stiffening element (61) constituting a secondary barrier to tearing , typically parallel to said first stiffening element forming said main barrier, said primer being located between said main and secondary barriers, so as to maintain said tear between said first stiffening element and said second stiffening element during said first opening. Said first and second stiffening elements forming said main and secondary barriers are preferably identical, continuous, parallel and spaced apart by a distance typically ranging from 1 to 20 mm, and preferably from 2 to 10 mm; they can optionally form a wire (50), a strip (52) or label (55) fixed to said face and having a weakening line (520, 550) typically obtained by mechanical or laser pre-cutting, said strip or label on one side (2) facing said strip on the other side (2 ').

This method has been illustrated in FIGS. 2a to 2c, 3a to 3c, 4a to 4b, 5, 12a to 12b, and 16.

It should also be noted that the two types of guide means can be combined, as illustrated in FIG. 12a, so that the tear in the packaging during the first opening follows a completely predetermined line.

As illustrated in all of the figures, said partition line, which generally runs along or merges with the line formed by the first stiffener (5), can be a line ensuring complete separation of said upper (11) and lower (12) parts. ). Indeed, it is generally more practical or aesthetic that it is so, but this in itself is in no way obligatory.

It is often advantageous for this partition line to be a transverse line, so as to ensure total opening of said bag, as illustrated for example in FIGS. 1a to 2c. However, it is possible to have a partial opening, as illustrated in FIGS. 3a to 4b.

Said first stiffening element (5, 50, 51, 52, 53, 54, 55) forming said barrier should be chosen by its nature, its mechanical characteristics or its thickness, so that the propagation energy of said tear is typically at least 20% higher at the crossing of said main barrier (5 ') than in the strip material (7) without stiffening element. However, in particular when the first stiffener (5) or the second stiffening element (61) are formed by incorporating an added element (wire, strip, etc.), the energy of propagation from the tear to the crossing of said main barrier (5 ') comprising said first stiffening element (5), or of the secondary barrier comprising said second stiffening element (61), can be much greater, at least twice greater, or even five times greater and even more in some case, with the propagation energy of the tear in the strip material itself, so that it becomes almost impossible that, on the first opening, the tear can get lost outside the "track" which was assigned when the packaging was designed.

All the figures, except FIG. 3 c, illustrate the case where said first stiffening element is constituted by an added element, typically by a wire (50) or a strip (51) secured to said side walls (2, 2 ').

Said thread (50) can be a textile thread made of natural, artificial or synthetic material, or a metallic thread, said thread having a breaking strength of at least 0.5 N.

Likewise, said strip (51) may be a strip of paper, or of metal, or of monolayer or multilayer plastic material, and optionally printed.

As illustrated in FIG. 3b, said first stiffening element (5) forming said barrier can consist of a relief pattern (53) typically obtained by localized deposition of material, for example by printing, so as to form a thick relief typically ranging from 20 to 200 μm, and thus locally increasing the thickness of said strip material by at least 20%. Thus, it may be advantageous to form said first stiffening element (5) as well as the second stiffening element (61) at the same time as the web material (7) intended to form the container is printed.

(D-

However, as illustrated in FIG. 3 c, said first stiffening element can consist of an additional thickness (54) of the material constituting said face (2, 2 ′), typically formed by punching or by extrusion of said typically plastic material. In this case, it may be advantageous to form two beads of material (54) constituting said stiffening element (5) and the second stiffening element (61) with a central thinning, and this typically when forming the sealed edges (3) with a tool hot enough to make the plastic flow, but cold enough not to seal the two sides (2, 2 '). Advantageously, in particular from an aesthetic point of view, said strip material (7) can be a multilayer material, said first stiffening element (5, 50, 51) being inserted between two layers (70) of said multilayer material, the two layers possibly being different or identical. Said strip material (7) may comprise at least one layer (70) of extruded thermoplastic material or at least two layers (70) of co-extruded thermoplastic material, or at least two layers (70) of complexed strip material, said stiffening element typically oriented in the "machine" MD direction of the strip material (70), as illustrated in FIGS. 7a to 8 and 12 to 14 where the stiffening element is a wire, but possibly in the "through" direction TD , as shown in Figure 15c. However, it would be possible according to the invention to insert between the layers a strip, or even discontinuous elements placed on a continuous support of the wire type (namely a typically one-dimensional product of very long length L (L "0) or of the type strip, namely a two-dimensional product of small relative width 1 (L "1> 0), and of small thickness.

The packaging according to the invention can typically be formed either from two strip materials (7), identical or different, by cutting the two strip materials, each forming a side wall (2, 2 ') of said packaging, and sealing the edges to form a sealed border (3), either from a single strip material, by folding, sealing and cutting, one side of said packaging forming a fold (15). Said sealing may typically be a heat sealing including compression of the edges, in particular so that each end of said member ^stiffener (5, 50, 51) is coated by said strip material (7) by localized creep of said strip material, so as not to affect the sealing of the packaging.

According to the invention, said strip material (7) can be chosen from - or can comprise - one or more of the following materials: paper, metal foil typically made of aluminum, film or a layer of oriented PET, PA, PP, PE or bi-oriented, possibly metallized, said material having a thickness comprised between 20 and 200 μm, said strip material being a material comprising from 1 to 5 layers (70).

When taking PE, it is preferable to take a tearable PE with a thickness at least equal to 60 μm.

According to a variant of the invention, the packaging can comprise, as illustrated in FIG. 12b, an attached bottom (18), so as to have a standing-up packaging. As also illustrated in FIGS. 12a and 12b, said first stiffener element (5) may have characteristics chosen on the basis of its ability to fold / unfold to allow reclosure of said packaging after said first opening. We can take for this a metal strip, typically aluminum, which can also be printed.

A particular object of the invention consists of a bag, typically with rectangular faces (2, 2 ') of multilayer material, typically comprising 2 to 4 layers, said first stiffening element on each face (2, 2') being opposite and constituted by a textile thread, typically made of PET or PA, parallel to said opening (13), and typically at a distance from this border of between 5 mm and 30 mm, so that said upper part (11) has , relative to said lower part, a small relative surface, typically less than 0.2 times the surface of said lower part.

Depending on the case, such a sachet can have its filling opening (13) in said upper part, as illustrated on most of the sachets represented in the figures, or in said lower part (12), as illustrated in FIG. 5, or also laterally as illustrated in FIG. 1d where the filling opening is perpendicular to the partition line formed by said main barrier.

Said first stiffening element (5), like the second stiffening element (61), can also be located on the interior and / or exterior face of said wall (2,2 ′). Thus, the invention also makes it possible to obtain all kinds of combinations depending on whether one considers the other face, the first stiffening element (5) or the second stiffening element (61). In addition, it is possible to combine, if necessary, several modalities for the first stiffening element (5) and for the guide means (6), depending on the technical, aesthetic, production or use requirements.

The first stiffening element (5), and optionally said guide means, can be constituted by or comprise a strip (51, 52), for example in the form of a typically extruded profile, as illustrated in FIGS. 10, 11, 16 In this case, it may be advantageous for said strip (51, 52) to also comprise a closing means, the strip on one side typically comprising a closing element cooperating with a complementary closing element, facing it. on the other side, said closure means being typically of the "ZIP" type and located below said first stiffening element in said lower part (12).

But, moreover, and independently of the stiffening element, the packaging according to the invention may comprise a closing means, a face (2) typically comprising a closing element cooperating with a complementary closing element, opposite, of the other face (2 '), said closure means being typically of the "ZIP" type and located below said first stiffening element in said lower part (12).

Another object of the invention consists of a method of manufacturing a packaging according to the invention in which: a) all or part of said strip material is formed by extrusion or co-extrusion, lamination or laminating ( 7) and in which this material is made integral, during said extrusion or co-extrusion, lamination or laminating, said first stiffening element (5, 50, 51) and, where appropriate said second stiffening element (61), said first stiffening element, and possibly said second stiffening element, being supplied, unrolled typically in the machine direction MD of the strip of material (7) and driven (s) by the advancement of said material. in strip (7) extruded or co-extruded, laminated or laminated, b) said container (1) is typically formed by forming a sealed border (3) of the faces (2, 2 ') formed from two strips of material (7) or from a single strip by folding, possibly forming said tear leader (4), and cutting said container.

According to another variant of the process of the invention: a) supplying said strip material (7) and said first stiffening element (5), and, where appropriate said second stiffening element (6), b) then forming said container (1) typically by forming a sealed border (3) of the faces (2, 2 ') formed from two strips of material (7) or from a single strip by folding, possibly forming said primer tearing (4), and by cutting said container, said stiffening element, and possibly said second stiffening element, being secured to said container typically by welding or gluing, outside or inside said packaging, during the formation of said container.

According to yet another variant of the process of the invention: a) supplying said strip material (7), applying or forming on said strip material, in a typically marked manner, said first stiffening element, b) then forming said container (1) typically by forming a sealed border (3) of the faces (2, 2 ') formed from two strips of material (7) or from a single strip by folding, possibly forming said primer tear (4), and by cutting said container.

Whatever the variant of the process of the invention, said first stiffening element (5), and where appropriate said second stiffening element (61), can (can) be coated or typically coated with glue or adhesive so that '(s) is (are) completely integral with said strip material (7) and that there is no risk of delamination and risk of loss of sealing of the packaging or increase in the permeability of the packaging.

Most often the materials forming the first stiffening element (5) and the second stiffening element (61) are compatible with the materials forming said strip material (7), but, with a choice of suitable glue or adhesive, it is virtually possible to adhere any type of first stiffening element (5) and second stiffening element (61) to said strip material (7).

Depending on the case, and in particular when the first stiffening element (5) and the second stiffening element (61) are inserted between the layers of strip material (7), the first (5) and / or second (61) ) stiffener element a thickness ER typically small compared to the thickness of the strip material. (7) Es - for example at least 4 times lower or even 8 times lower (10 μm vs 80 μm). On the other hand, when, for example, a strip (51, 52), or a label (55) is used, its thickness may, if necessary, be close to that of the strip material. Advantageously, said first stiffening element (5) and said second stiffening element (61) can advantageously be identical and be formed simultaneously, the strip material (7) being able to be oriented or not.

Most often, said strip material (7) can be chosen from the following multilayer materials: PET / PP, PET / A1 / PP, PET / A1 / OPA / PP, PET / A1 / PE, PET / A1 / OPA / PE, PET / OPA / A1 / PP, PET / OPA / A1 / PE, PET / PE, OPP / PE, OPP / PP, OPP / OPP, OPA / PP, OPA / PE, where "Al" (also known as "alu" or "ALU" in the figures) designates thin aluminum foil, typically less than 20 μm, where OPP and OPA denote oriented PP and PA respectively, "/" symbolically denoting the separation between distinct layers .

According to the invention, it is also possible to supply said material with a strip, and, after forming said container, condition said product (8) in said container, and close said packaging, typically before possibly forming said tear primer (4) and cut said container, so as to implement the process known as FFS "Form-Fill-Seal".

In this case, said supplied strip material may comprise said first stiffening element (5) oriented in the transverse direction TD, perpendicular to the machine direction MD of unwinding of said strip material. FIGS. 15a to 15c illustrate a way of industrially manufacturing a strip material comprising a thread oriented not in the machine direction, as in FIG. 7a, but in the cross direction. We have shown, in dotted lines, in Figures 15b and 15c, the possibility of having a second wire forming the second stiffening element (61).

According to a variant of the process, said supplied strip material not comprising said first stiffening element (5), said first stiffening element (5), and possibly said guide means (6) if necessary, is formed or applied to the faces ( 2) and (2 ') during the implementation of said FFS process.

According to the invention, said first stiffening element (5) - and possibly said guide means (6) if necessary - can be a strip applied to the inside of said container, so that nothing is visible from the outside, and / or so that the outer surface of the bag is smooth. FIG. 16 illustrates this possibility of a sachet, where the two side walls (2) and (2 ′) are shown before face-to-face welding, the two upper strips (51) forming said guide means (6,61), both lower strips forming said stiffening element (5). All these strips can be fixed to the side walls either during the manufacture of said strip material, or during the manufacture of said container.

Another object of the invention consists of the strip material or film (7) intended for implementing the method according to the invention. This material or film, intended for use on automatic filling machines of the FFS type, comprises said first stiffening element (5), and optionally said guiding means, said first stiffening element (5), and possibly said guiding means, being oriented in the machine direction MD or in the cross direction TD. This film can be obtained, as already indicated by different technologies including lamination. The stiffening element (5) and the guide means are typically introduced during lamination, preferably between the two films forming the layers (70). According to one modality, their positioning in the width of the strip material is adjustable, and the functionality will be obtained in the longitudinal direction or MD machine. It is of course possible to introduce as many stiffening elements or guide means as necessary on the width of the strip material (7), in order to: - guide the tear, - and / or meet the needs of several poses which will be cut later,

- and / or integrate the functionality sought on the front and / or back.

It is only as a block diagram that, in FIG. 7a, the strip material (7) comprises only two wires (50).

The invention finds an application in the packaging of all types of products, whether for example food products, cosmetic products, or even maintenance products.

EXAMPLES OF REALIZATION

All the figures constitute exemplary embodiments of sachets (1).

For the manufacturing tests, PET / A1 / PP with a thickness of 12 μm / 9 μm / 90 μm, PET / A1 / OPA / PP described in FIGS. 12 to 14, and PET / PE, and LDPE of 80 μm.

As the first stiffening element (50) and as the second stiffening element (61), a PA6 / 6 nylon thread of 13 strands of 10 μm diameter each was used.

In the case of laminating layers (70) according to FIGS. 7a and 12 to 14, two wires (50.61) at 7 mm are inserted, without having to modify the "standard" laminating speed. on the other, so as to simultaneously form the stiffening element (50) and the second stiffening element (51).

Sterilizable bags have also been made.

Tests have also been carried out using as the first stiffening element (50) a metal wire or "anti-theft" strip designed to alert, typically trigger a ring, in the event of fraudulent passage between the gates of cash registers in stores.

Reclosable sachets have also been made using as a first stiffening element (5), on each face, an aluminum strip 40 μm thick and 20 mm wide, or by incorporating a "ZIP" type closure. All the bags produced have been tested by a panel of people representing "average consumers", the opening of the bags having to be carried out without particular attention, as in everyday life.

The results clearly showed that, thanks to the means of the invention, the tear propagated in a controlled and channeled manner.

ADVANTAGES OF THE INVENTION

The invention has numerous advantages.

On the one hand, it discloses a new type of packaging guaranteeing its integrity when it is first opened.

It also discloses the very many ways of implementing the invention.

It also discloses possibilities for simultaneously incorporating other functions into the packaging (reclosing, detection, etc.).

Finally, depending on the procedures, it can possibly be implemented without significant additional cost.

LIST OF REFERENCES

Bag - Container 1

Partition line 10 Upper part 11

Lower part 12

Sachet filling opening ... 13

Sealed filling border 14

First opening area or side ... 15 First opening hole ... 150

Fold 16

Bottom of the bag 17

Stand back for standing ... 18

Opening side edge 19 Side walls 2, 2 '

Border with 2 and 2 'seal of the bag 3 Tear leader 4

Stiffening element 5

Main barrier = 5 + 2/2 '5'

Thread 50 Strip, tab, label 51

Strip with weakening line 52

Line of Weakness 520

Embossed motif - Localized deposit of material 53

Material allowance 54 Printed label (metallic) 55, 55 '

Line of weakening 550

Guide 6

Oriented material (O =>) 60

S econd stiffener type 5 61 14 "reinforced" sealing edge 62

Strip material to form 2.2 'and 1 7

Multilayer material layers 70

Cutting lines 71

Coil 72 Glue - adhesive 73

Product contained in the bag 8

Claims

.- CLAIMS

1. Packaging of a product (8), typically in the form of a sachet, forming a container (1) comprising two side walls (2, 2 '), a bottom (17), and a filling opening ( 13), able to be closed after packaging of the product (8) in said packaging, said container (1) being formed from a strip material (7) which can be torn manually, typically of plastic material, and comprising a first zone opening (15) provided with a tear primer (4) typically formed on an edge (3, 14) of said container (1) for the first opening of said packaging once filled and sealed, said edge (3, 14 ) being typically formed by sealing the edges of the two side walls (2, 2 '), and characterized in that, in said zone of first opening: a) each side wall (2, 2') comprises, typically facing and of in parallel, at least one first stiffening element (5, 50, 51, 52, 53, 54) locally reinforcing nt

Said side wall and constituting, with said associated side wall, a main barrier (5 ′) to said typically continuous tear, said stiffening element being chosen so that the propagation energy of said tear is less than the energy breaking of said main barrier, so that said main barrier (5 ′) constitutes a partition line of said packaging, with an upper part (11) intended

20 to be torn, in whole or in part, during said first opening, and a lower part (12) intended to serve as a container for said product (8), b) said tear primer (4) is located, entirely or in part, in said upper part (11) and at a distance from said first stiffening element typically less than 10 mm,

C) each side wall (2, 2 ′) comprises means for guiding (6, 60, 61) of said tear during said first opening, so that said tear can only deviate from said stiffening element 'at most 20 mm, d) said guide means (6) is formed by: dl) a choice of a strip material (7, 60) oriented in a direction denoted ^' 30 symbolically "O =>", l ' tear propagation energy in said direction typically being at least 1.5 times lower than in a perpendicular direction ,, d2) a relative orientation of said direction "O =>" with respect to the orientation of said partition line formed by said first stiffening element, so that the tear propagates along said partition line of said packaging.

2. Packaging according to claim 1 wherein said means for guiding said partition line and said direction forms an angle α formed typically ranging from 0 ° to 45 °, and wherein said packaging comprises one or two primers (4), they -same possibly forming an acute angle oriented towards said partition line.

3. Packaging according to any one of claims 1 to 2 wherein said guide means (6) comprises, on each side wall (2, 2 '), and typically in parallel, a second stiffening element (61) constituting a secondary barrier at the tear, typically parallel to said first stiffening element forming said main barrier, said primer being located between said main and secondary barriers, so as to maintain said tear between said first stiffening element and said second stiffening element during said first opening.

4. Packaging according to claim 3 wherein said main and secondary barriers are identical, continuous, parallel and spaced by a distance typically ranging from 1 to 20 mm, and preferably from 2 to 10 mm, said main and secondary barriers possibly forming a wire (50), a strip (52) or label (55) fixed to said face and having a weakening line (520, 550) typically obtained by mechanical or laser pre-cutting, said strip or label of a face (2) being opposite said strip on the other face (2 ').

5. Packaging according to any one of claims 1 to 4 wherein said partition line is a line ensuring complete separation of said upper (11) and lower (12) parts.

6. Packaging according to claim 5 wherein said partition line is a transverse line, so as to ensure a total opening of said bag.

7. Packaging according to any one of claims 1 to 6 wherein said first stiffening element (5, 50, 51, 52, 53, 54, 55) forming said barrier is chosen by its nature, its mechanical characteristics or its thickness, so that the propagation energy of said tear is typically at least 20% higher when crossing said main barrier (5 ′) than in the strip material (7) without a stiffening element.

8. Packaging according to claim 7 wherein said first stiffening element is constituted by an insert, typically by a wire (50) or a strip (51) secured to said side walls (2, 2 ').

9. Packaging according to claim 8 wherein said thread (50) is a textile thread made of natural, artificial or synthetic material, or a metallic thread, said thread having a breaking strength of at least 0.5 N.

10. Packaging according to claim 8 wherein said strip (51) is a strip of paper, or metal, or monolayer or multilayer plastic, and optionally printed.

11. Packaging according to any one of claims 1 to 7 wherein said first stiffening element forming said barrier consists of a relief pattern (53) typically obtained by localized deposition of material, for example by printing, so as to form a relief d thickness typically ranging from 20 to 200 μm, and thus locally increasing the thickness of said strip material by at least 20%.

12. Packaging according to any one of claims 1 to 7 wherein said first stiffening element consists of an extra thickness (54) of the material constituting said face (2, 2 '), typically formed by punching or by extrusion of said material.

13. Packaging according to any one of claims 1 to 12 wherein said strip material (7) is a multilayer material, said stiffening element (5, 50, 51) being inserted between two layers (70) of said multilayer material, the two layers may be different or identical.

14. Packaging according to claim 13 wherein said strip material (7) comprises at least one layer (70) of extruded thermoplastic material or at least two layers (70) of co-extruded thermoplastic material, or two layers (70) of complexed strip material, said stiffening element being typically oriented in the "machine" MD direction of the strip material (70).

15. Packaging according to any one of claims 1 to 14 formed either from two strip materials, identical or different, by cutting the two strip materials, each forming a side wall (2, 2 ') of said packaging, and sealing the edges to form an edge (3), either from a single strip material, by folding, sealing and cutting, one side of said packaging forming a fold (15).

16. Packaging according to any one of claims 13 to 14 and claim 15 wherein said seal is typically a heat seal comprising a compression of the edges so that each end of said first stiffening element (5, 50, 51) is coated by said strip material (7) by localized creep of said strip material.

17. Packaging according to any one of claims 1 to 16 in which said strip material (7) is chosen from or comprises one or more of the following materials: paper, typically aluminum foil, film or a layer of PET, PA, PP , PE oriented or bi-oriented, possibly metallized, said material having a thickness of between 20 and 200 μm, said strip material being a material comprising from 1 to 5 layers (70).

18. Packaging according to any one of claims 1 to 17 comprising an attached bottom (18), so as to have a standing packaging.

19. Packaging according to any one of claims 1 to 18 wherein said first ^has 5 stiffening element (5) is typically metallic, and has characteristics chosen to allow detection of said packaging, or its reclosing after said first opening.

20. Packaging according to any one of claims 1 to 19 consisting of a sachet, 0 typically with rectangular faces (2, 2 ') of multilayer material, typically comprising 2 to 4 layers, said first stiffening element on each face (2, 2' ) being facing and constituted by a textile thread, typically made of PET or PA, parallel to said opening (13), and typically at a distance from this border of between 1 and 50 mm, and preferably between 5 mm and 30 mm , so that said upper part 5 (11) has, relative to said lower part, a small relative surface, typically less than 0.2 times the surface of said lower part.

21. Packaging according to any one of claims 1 to 20 wherein said first stiffening element is located on the inner and / or outer face of said wall (2,2 '). 0

22. Packaging according to any one of claims 1 to 21 wherein said first stiffening element is constituted by or comprises a strip (51, 52) forming a typically extruded profile.

23. Packaging according to claim 22 wherein said strip (51, 52) also comprises a closing means, the strip on one side typically comprising a closing element cooperating with a complementary closing element, facing the other. face, said closure means being typically of the "ZIP" type and located below said first stiffening element in said lower part (12).

24. Packaging according to any one of claims 1 to 22 comprising a closure means, a face (2) typically comprising a closure element cooperating with a complementary closure element, facing the other face (2 '), said closure means being typically of the "ZIP" type and located below said first stiffening element in said lower part (12).

25. A method of manufacturing a packaging according to any one of claims 1 to 24 in which: a) all or part of said strip material (7) is formed by extrusion or co-extrusion, lamination or laminating and in which this first stiffening element (5, 50, 51) and, where appropriate said second stiffening element (61), said first stiffening element, and are joined to this material, during said extrusion or co-extrusion, lamination or laminating, and possibly said second stiffening element, being supplied (s) and unrolled (s) typically in the machine direction MD of the strip of material (7) and driven (s) by the advancement of said strip material (7) extruded or co- extruded, laminated or laminated, b) said container (1) is typically formed by forming a sealed border (3) of the faces (2, 2 ') formed from two strips of material (7) or from a single strip by folding, possibly forming said amo rce of tear (4), and cutting said container.

26. A method of manufacturing a packaging according to any one of claims 1 to 12 and 15 to 24 wherein: a) supplying said strip material (7) and said first stiffening element (5), and, where appropriate said second stiffening element (6), b) then said container (1) is typically formed by forming a sealed border (3) of the faces (2, 2 ') formed from two strips of material (7) or from a single strip by folding, possibly forming said tear leader (4), and cutting said container, said first stiffening element, and optionally said second stiffening element, being secured to said container typically by welding or gluing, to inside or outside of said package, during the formation of said container.

27. A method of manufacturing a packaging according to any one of claims 1 to 12 and 15 to 24 wherein: a) supplying said strip material (7), applying or forming on said strip material, typically marked , said first stiffening element, b) then said container (1) is typically formed by forming a sealed border (3) of the faces (2, 2 ') formed from two strips of material (7) or from a single strip by folding, possibly forming said tear leader (4), and cutting said container.

28. Method according to any one of claims 25 to 27 wherein said first stiffening element (5), and where appropriate said second stiffening element (61), is (are) coated or typically coated with glue or adhesive so that 'it (s) is (are) completely integral with said strip material (7).

29. Method according to any one of claims 25 to 28 wherein said first stiffening element (5) and said second stiffening element (61) are identical and are formed simultaneously, the strip material (7) being able to be oriented or not.

30. Method according to any one of claims 25 to 29 in which said strip material (7) is chosen from the following multilayer materials: PET / PP, PET / A1 / PP, PET / A1 / OPA / PP, PET / A1 / PE, PET / A1 / OPA / PE, PET / OPA / A1 / PP, PET / OPA / A1 / PE, PET / PE, OPP / PE, OPP / PP, OPP / OPP, OPA / PP, OPA / PE:

31. The method as claimed in any one of claims 25 to 30, in which said strip material is supplied, and, after said container is formed, said product (8) is packaged in said container, and said packaging is closed, typically before possibly forming said tear leader (4) and cutting said container, so as to implement the process called FFS "Form-Fill-Seal".

32. The method of claim 31 wherein said supplied strip material comprises said first stiffening element (5) oriented in the TD direction, perpendicular to the direction MD of unwinding of said strip material.

33. The method of claim 31 wherein said supplied web material does not include said first stiffener (5), and wherein said first stiffener (5) is formed or applied during the implementation of said FFS process.

34. Method according to any one of claims 26 to 31 and 33 wherein said first stiffening element (5) is a strip applied to the interior of said container.

35. A strip material or film intended for implementing the method according to any one of claims 25 and 27 to 34 comprising said first stiffening element (5), and optionally said guide means, said first stiffening element (5), and possibly said guide means, being oriented in the machine direction MD or in the transverse direction TD.