WO2019193473A1

WO2019193473A1 - Laminated material and process for its manufacture, as well as sheet and container obtained from this laminated material

Info

Publication number: WO2019193473A1
Application number: PCT/IB2019/052593
Authority: WO
Inventors: Valerio Binda
Original assignee: Masterpack SpA
Current assignee: Masterpack SpA
Priority date: 2018-04-05
Filing date: 2019-03-29
Publication date: 2019-10-10
Anticipated expiration: 2020-10-05
Also published as: IT201800004234A1; EP3774325A1

Abstract

Laminated material comprising at least one first layer (1) and at least one second layer (2) joined by adhesive placed between these two layers (1, 2), wherein at least one first incision (7) is made in the first layer (1), so as to form in the first layer (1) at least one portion (1a) that can be separated from the second layer (2) while keeping the remaining portion (1b) of the first layer (1) joined to the second layer (2), and in which at least one second incision (8) is made in the second layer (2), so as to form in the second layer (2) at least one portion (2a) which can be separated from the first layer (1) while keeping the remaining portion (2b) of the second layer (2) joined to the first layer (1), wherein the adhesive between the first layer (1) and the second layer (2) defines at least one first adhesive region (5) and at least one second adhesive region (6) which are separated from each other by at least one non-adhesive region (4), wherein at least one portion of the first incision (7) is arranged above the non-adhesive region (4). The present description also relates to a process for manufacturing this laminated material, as well as a sheet and a container obtained from this laminated material.

Description

Laminated material and process for its manufacture, as well as sheet and container obtained from this laminated material

TECHNICAL FIELD

The present description relates to a laminated material for containers, in particular for food use. The present description also relates to a process for manufacturing this laminated material, as well as a sheet and a container obtained from this laminated material.

FRAMEWORK OF THE DESCRIPTION

A known laminated material is provided with two layers of plastic material joined by a pressure adhesive also known as PSA (Pressure-Sensitive Adhesive), which adhesive allows the separation of a tongue obtained by incising one of the two layers.

WO 2015/145338 Al describes a laminated material provided with a non-adhesive region disposed between the two layers along an edge of the laminated material or a series of non-adhesive regions arranged transversely at constant distances. In both cases, the non-adhesive region is arranged outside the sheet obtained from this laminated material to form a container, in particular to close a tray. Moreover, the outer layer is not provided with incisions, so that the container is relatively difficult to manufacture and/or use.

WO 2011/032064 Al and US 2005/0276525 Al describe laminated materials provided with a non-adhesive region disposed in a limited area of the edge of the sheet which forms the container, close to an incision of the outer layer, so that also in this case the container is relatively difficult to manufacture and/or use.

SUMMARY OF DESCRIPTION

The object of the present description is therefore to provide a laminated material free from these drawbacks. This object is performed with a laminated material, a manufacturing process, a sheet and a container, whose main characteristics are specified in the attached claims.

Thanks to the particular shape and to the particular arrangement of the non-adhesive region, namely a region substantially free of adhesive or in any case less adhesive than the adjacent regions, arranged between two adhesive regions, the laminated material according to the present description can be advantageously used for food containers which can be easily manufactured, as well as opened and closed, even several times, during use. This advantage can be improved thanks to the particular shape and the particular arrangement of the incisions in the inner layer and in the outer layer.

In particular, the container comprising the laminated material does not require protuberances or labels for opening the container itself, thanks to the presence of the non adhesive region and to the arrangement of the first incision with respect to this region, so as to limit the overall dimensions and/or improve the appearance of the container.

Moreover, the laminated material object of the present description allows a saving of adhesive material and allows to make the incisions of both layers through die-cutting, thus allowing to simplify the manufacturing process, especially if the laminated material is formed in a continuous strip from which a series of sheets suitable for closing food containers, for example bags or trays, can be obtained with an automated process and/or an automatic machine.

Furthermore, the laminated material can be advantageously used to close containers comprising two trays independently accessible one from the other.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages and characteristics of the laminated material, of the sheet, of the container and of the process according to the present description will be apparent to those skilled in the art from the following detailed and non-limiting description of some embodiments thereof with reference to the attached drawings in which:

figure 1 shows a top view of a first embodiment of the laminated material;

figure 2 shows a bottom view of the laminated material of figure 1;

figure 3 shows section III-III of figure 1 (with enlarged thicknesses); figure 4 shows a top view of a container comprising a sheet obtained from the laminated material of figure 1 ;

figure 5 shows the container of figure 4 during the opening;

figure 6 shows a side view of the container of figure 4;

figure 7 shows a side view of the container of figure 5;

figure 8 shows a top view of a container comprising a sheet obtained from a second embodiment of the laminated material;

figure 9 shows a top view of a container comprising a sheet obtained from a third embodiment of the laminated material;

figure 10 shows a top view of a fourth embodiment of the laminated material; figure 11 shows a top view of a fifth embodiment of the laminated material.

EXEMPLARY EMBODIMENTS

With reference to figures 1 to 3, it can be seen that the laminated material according to the present description comprises at least one first layer 1 or outer layer, which is adapted to be facing the outside of a container, for example a bag or a tray. The first layer 1 is joined to at least one second layer 2 or inner layer, suitable to be facing towards the container, by at least one layer of adhesive material arranged between the first layer 1 and the second layer 2, so as to form the laminated material, preferably continuous to be wound on a roller. Preferably, the width and/or the length of the first layer 1 are substantially equal respectively to the width and to the length of the second layer 2. In figures 1 and 2 two outer edges of the laminated material are shown with a mixed line, suitable to delimit a portion which can be repeated transversely and/or longitudinally in the laminated material, which can therefore have a greater extension, especially in length, than that shown in the figures, so as to form a strip to be wound on a roller. The first layer 1 and/or the second layer 2 preferably comprise at least one film of plastic material, for example polypropylene, having a thickness of between 10 and 40 microns, while the adhesive is preferably a pressure-sensitive adhesive which allows both the separation of the first layer 1 from the second layer 2 by manual traction and their subsequent adhesion by pressing the first layer 1 on the second layer 2, and/or vice versa. Preferably, the first layer 1, the second layer 2 and the adhesive are substantially transparent, so that the resulting laminated material is substantially transparent.

In particular, the adhesive is arranged between the first layer 1 and the second layer 2 so as to leave at least one non-adhesive region 4, namely substantially free of adhesive or otherwise with a reduced adhesiveness, between the first layer 1 and the second layer 2, which is shown with dashed lines in figures 1 and 2 and is visible in figure 3. The non adhesive region 4 can also be obtained by applying only within the perimeter of the same region a substance that completely or partially neutralizes a layer of adhesive uniformly applied between the layers 1 and 2. Therefore, the laminated material comprises at least one first adhesive region 5 and at least one second adhesive region 6, which regions are separated by the non-adhesive region 4 at least along most of their extension. The non adhesive region 4 preferably forms a strip which is continuous and/or substantially parallel to a longitudinal axis L which can correspond to the direction of winding of the laminated material on a roller. In the present embodiment the first adhesive region 5 of the laminated material and the second adhesive region 6 of the laminated material have a substantially rectangular shape and are disposed respectively to the left and to the right of the non-adhesive region 4.

At least one first incision 7 is made in the first layer 1, so as to form in the first layer 1 a portion la which can be separated from the second layer 2 while keeping the remaining portion lb of the first layer 1 joined to the second layer 2. At least one portion of the first incision 7 is arranged on the non-adhesive region 4. In the present embodiment two first incisions 7 extend into the first layer 1 starting from the non-adhesive region 4 towards the first adhesive region 5 or the second adhesive region 6, respectively.

At least one second incision 8, in particular in the shape of a U or V, is made in the second layer 2, so as to form in the second layer 2 a tongue-shaped portion 2a which can be separated from the first layer 1 while keeping the remaining portion 2b of the second layer 2 joined to the first layer 1. At least one end of the second incision 8 may be provided with a curl 9.

The second incision 8 can be at least partially surrounded by one or more first incisions 7. In the present embodiment the first incisions 7 have at least one first section 7a which is substantially parallel to the longitudinal axis L, is arranged on the non- adhesive region 4 and/or extends on the opposite side with respect to the tip of the tongue formed by the second incision 8, as well as a second portion 7b which forms an obtuse angle with the first portion 7a and/or is arranged next to the tip of the tongue over the adhesive region 5 or 6. The sub-portion lc of the portion la of the first layer 1 which is included between the first sections 7a of the two first incisions 7 forms a gripping tab which can be easily separated from the second layer 2, thanks to the non-adhesive region 4 arranged under the sub-portion lc, and grasped by a user to separate the portion la from the portion lb of the first layer 1.

The longitudinal axis L corresponds preferably to an axis of symmetry for the non adhesive region 4 and/or the incisions 7 and 8.

A portion of the laminated material can be cut and removed to be used as a sheet to close a container. In particular, figure 2 shows with a dashed line the edge of the sheet 3 of the laminated material that can be cut and applied, for example by heat- sealing, on the edge (also shown with a dashed line) of a container 10, for example a food tray. The second layer 2 can therefore be made of a heat-sealable material. The non-adhesive region

4 and/or the first incisions 7 preferably connect together two points of the edge of the portion 3. In particular, the non-adhesive region 4 connects to each other two opposite sides of the edge of the container 10, so that the adhesive regions 5, 6 are completely separated from each other by the non-adhesive region 4.

As shown in figures 4 to 7, the sheet 3 can for example be used to make a food container 10 which can be easily opened and closed even several times during use. figures

5 and 7 show that, thanks to the non-adhesive region 4 and the first incisions 7, when a free edge of the portion la of the first layer 1 along the sheet 3, namely the sub-portion lc, is pulled by a user upwards, that is in the direction indicated by the arrow F, the portion la of the first layer 1 separates from the remaining portion lb of the first layer 1 and carries with it the tongue- shaped portion 2a of the second layer 2. In this way, the sheet 3 forms an opening 3a through which it is possible to access the inside of the container 10. By applying the portion la of the first layer 1 back to its initial position on the adhesive regions 5 and 6, the opening 3a is closed. The tip of the tongue formed by the second incision 8 is preferably directed towards the sub-portion lc of the portion la of the first layer 1 arranged on the non-adhesive region 4. With reference to figure 8, it is seen that in the sheet 3 obtained from the laminated material according to the second embodiment the first incision 7 can have a substantially U-shaped shape further comprising a convex portion, in particular semicircular or lunette shaped, which defines a sub-portion lc of the portion la of the first layer 1 which is arranged at the non-adhesive region 4 and can act as a gripping tab for opening the container. The second incision 8 can have a shape similar to that of the first incision 7 but smaller, so as to be at least partially surrounded, in particular completely, by the first incision 7. The tip of the tongue formed by the second incision 8 faces the sub-portion lc of the first layer 1.

With reference to figure 9, it is seen that in the sheet 3 obtained from the laminated material according to the third embodiment, the first incision 7 can have a rectilinear shape and be placed at the non-adhesive region 4, in particular being substantially parallel to the latter, more in particular substantially parallel to the longitudinal axis L. The second incision 8 may be semicircular or lunette-shaped so as to form a tongue with the tip facing the first incision 7. The sub-portions lc of the portion la of the first layer 1 which are arranged on the non-adhesive region 4 near the edges of the sheet 3 act as a gripping tab to open the container.

With reference to figure 10, it is seen that in a fourth embodiment, similar to the previous embodiments, the second layer 2 of the laminated material can be heat-welded on the edge (shown with dotted lines) of a container 10 comprising at least two adjacent trays lOa, lOb which can be placed side by side or joined together along two adjacent edges. The laminated material can be cut to obtain a sheet 3 having a perimeter equal or slightly greater than the perimeter of the container 10. The second layer 2 has two second tongue-shaped incisions 8, each arranged on a tray lOa or lOb of the container 10. The non-adhesive region 4 is arranged between the two second incisions 8 and covers at least partially the adjacent edges of the trays lOa, lOb.

At least one first incision 7 is made in the first layer 1 at the non-adhesive region 4 and, consequently, also at the region between the two trays lOa and lOb. The first incision 7 extends along the longitudinal direction L of the laminated material and can be substantially rectilinear, curvilinear or wavy, as in the present embodiment, so as to form in the first layer 1 one or more gripping tabs lc close to the edge of the sheet 3. With reference to figure 11, it is seen that the fifth embodiment of the laminated material differs from the fourth embodiment in that the first incision 7 has a substantially more wavy shape with at least two loops forming gripping tabs lc which are arranged above the non-adhesive region 4 at the ends of the adjacent edges of the trays lOa and lOb. The first layer 1 further comprises one or more further incisions 11 having for example a shape substantially of an arc of a circle or an ellipse, with a convex portion facing towards the first incision 7. The ends of the further incisions 11 may form a curl. The further incisions 11 can therefore delimit a portion of the first layer 1 which remains attached to the second layer 2, detaching itself from the first layer 1 with a controlled tearing between the two curls, so as to act as a seal to highlight a separation of the first layer 1 from the second layer 2, namely the opening of the container 10. The further incisions 11 can occupy on the first layer 1 at least one surface equal to a circle having a diameter of at least 13 mm, preferably greater than 15 mm, so that a user can insert a finger in the hole left in the first layer 1 by the portion delimited by a further incision 11 and remained adherent to the second layer 2.

In a first operative step of the manufacturing process of the laminated material the first layer 1, wound on a first roller, is pulled towards one or more first auxiliary rollers which apply on one side of the first layer 1 at least one layer of adhesive taken by a first auxiliary roller from a tub. Specifically, said adhesive layer is applied by two first auxiliary rollers continuously on the adhesive regions 5 and 6, while leaving between them a space which thus forms the non-adhesive region 4. Therefore, the non-adhesive region 4 preferably extends along the whole feed direction L of the laminated material. The first layer 1 provided with the non-adhesive region 4 and the adhesive regions 5, 6 is then joined to the second layer 2 by second auxiliary rollers, so as to obtain a laminated material which can be wound on a third roller. In alternative embodiments, the adhesive can be applied on the second layer 2 and/or the non-adhesive region 4 can be obtained by completely or partially removing or deactivating with physical and/or chemical treatments a layer of adhesive applied on the first layer 1 and/or on the second layer 2. Before being wound on said third roller, at least one mechanical die-cutter, in particular a roller die-cutter, forms at least one first incision 7 in the first layer 1 and/or at least one second incision 8 in the second layer 2, in particular longitudinal and/or transverse series of first incisions 7 and second incisions 8 placed at substantially constant distances from each other. The first incision 7 and/or the second incision 8 can also be made before joining the first layer 1 to the second layer 2.

In a subsequent step, the laminated material can be taken from the third roller and cut to obtain a plurality of sheets 3, each provided with at least one non-adhesive region 4, at least two adhesive regions 5, 6, at least one first incision 7 and at least one second incision 8, which can be used to make containers for food use, for example as a cover for a container 10 in which the second layer 2 is joined to its edge by adhesive or heat-sealing.

Possible variations or additions can be made by those skilled in the art to the embodiments described and illustrated herein, remaining within the scope of the following claims. In particular, further embodiments may comprise the technical characteristics of one of the following claims with the addition of one or more technical features described in the text or illustrated in the drawings, taken individually or in any combination thereof.

Claims

1. Process for manufacturing laminated materials, which comprises the following operative steps:

joining at least one first layer (1) to at least one second layer (2) by means of adhesive placed between these two layers (1, 2);

making at least one first incision (7) in the first layer (1), so as to form in the first layer (1) at least one portion (la) which can be separated from the second layer (2) while keeping the remaining portion (lb) of the first layer (1) joined to the second portion (2);

making at least one second incision (8) in the second layer (2), so as to form in the second layer (2) at least one portion (2a) which can be separated from the first layer (1) while keeping the remaining portion (2b) of the second layer (2) joined to the first layer (1),

characterized in that the adhesive between the first layer (1) and the second layer (2) defines at least one first adhesive region (5) and at least one second adhesive region (6) which are separated from each other by at least one non-adhesive region (4), wherein at least one portion of the first incision (7) is arranged above the non-adhesive region (4).

2. Process according to the preceding claim, wherein the first incision (7) and the second incision (8) are made respectively in the first layer (1) and in the second layer (2) after the first layer (1) has been joined to the second layer (2).

3. Laminated material comprising at least one first layer (1) and at least one second layer (2) joined by adhesive placed between these two layers (1, 2), wherein at least one first incision (7) is made in the first layer (1), so as to form in the first layer (1) at least one portion (la) that can be separated from the second layer (2) while keeping the remaining portion (lb) of the first layer (1) joined to the second layer (2), and in which at least one second incision (8) is made in the second layer (2), so as to form in the second layer (2) at least one portion (2a) which can be separated from the first layer (1) while keeping the remaining portion (2b) of the second layer (2) joined to the first layer (1), characterized in that the adhesive between the first layer (1) and the second layer (2) defines at least one first adhesive region (5) and at least one second adhesive region (6) which are separated from each other by at least one non-adhesive region (4), wherein at least one portion of the first incision (7) is arranged above the non-adhesive region (4).

4. Process or laminated material according to one of the preceding claims, wherein the non-adhesive region (4) forms a strip which is continuous and/or substantially parallel to a longitudinal axis (L) of the laminated material.

5. Process or laminated material according to the preceding claim, wherein the longitudinal axis (L) corresponds to an axis of symmetry for the non-adhesive region (4) and/or the incisions (7, 8).

6. Process or laminated material according to one of the preceding claims, wherein the first incision (7) extends in the first layer (1) from the non-adhesive region (4) to an adhesive region (5, 6).

7. Process or laminated material according to one of the preceding claims, wherein at least two first incisions (7) have at least one first portion (7a) which is arranged above the non-adhesive region (4) and/or extends from the opposite side with respect to the tip of a tongue formed by the second incision (8), as well as a second portion (7b) which forms an obtuse angle with the first portion (7a) and/or is arranged alongside the tip of this tongue above an adhesive region (5, 6).

8. Process or laminated material according to one of the preceding claims, wherein the first incision (7) at least partially surrounds the second incision (8).

9. Process or laminated material according to one of the preceding claims, wherein the first incision (7) comprises a convex portion defining a sub-portion (lc) of the first layer (1) which can be separated from the second layer (2) and is arranged at the non-adhesive region (4).

10. Process or laminated material according to one of the preceding claims, wherein the first incision (7) has a substantially wavy shape.

11. Process or laminated material according to one of the preceding claims, wherein the first layer (1) comprises one or more further incisions (11) having a convex portion facing the first incision (7).

12. Sheet (3) obtained by cutting and removing a portion of the laminated material according to one of claims 3 to 11, wherein this portion comprises at least one non-adhesive region (4), at least two adhesive regions (5, 6), at least one first incision (7) and at least one second incision (8).

13. Sheet (3) according to the preceding claim, wherein the two adhesive regions (5, 6) are completely separated from each other by the non-adhesive region (4).

14. Container (10) comprising at least one sheet (3) according to claim 12 or 13.

15. Container (10) according to the preceding claim, wherein the container (10) comprises at least one tray with an edge and the sheet (3) is applied along this edge.

16. Container (10) according to the preceding claim, wherein the container (10) comprises at least two trays (lOa, lOb) and the non-adhesive region (4) is arranged between these two trays (lOa, lOb).

17. Container (10) according to the preceding claim, wherein the first incision (7) is arranged between the two trays (lOa, lOb).