MOISTURE-BARRIER PACKAGING

Description

CORRESPONDING APPLICATIONS

The present application claims priority to earlier European application No EP22172784-5 filed on May 11, 2022 in the name of AISAPACK HOLDING SA, the content of this earlier application being incorporated in its entirety by reference in the present application.

TECHNICAL FIELD

The field of the invention is packaging based on biosourced and/or biodegradable and/or recyclable materials. The invention relates more specifically to packaging with low environmental impact. The invention applies to cylindrical packagings that require good moisture-barrier properties. The invention applies in particular to cellulose-based packaging. The invention is notably in the field of packaging for dry products.

PRIOR ART

Publication US 2013/153586 discloses a package for ice cream consisting of a) a container component made of polystyrene comprising a base and a side wall extending from the perimeter of the base to form the cavity of the container component, and b) a closing means removable manually and comprising a top side adapted to seal the cavity of the container component and a side wall extending from the perimeter of the top side and adapted to encircle the side wall of the container component.

Publication U.S. Pat. No. 5,348,180 discloses a container having a tamper-evident seal. The container, suitable for receiving and shipping various products, includes a hollow body member and a removable cover positioned on an open upper end of the body member and has a tamper-evident seal device connecting the body member and the cover to evidence any premature removal of the cover. The seal device includes two sets of superimposed apertures extending through the body member and the cover, a closed sealing wire or member extending through the sets of apertures and around respective inside and outside portions of the body member and cover between the sets of apertures and being sealed to form a closed loop. A patch member is secured to the inside surface of the body member and covers the apertures to prevent contaminants from entering the container through the apertures and to strengthen the area of the body member having the apertures. The patch member preferably defines a guided passageway between the apertures so that the sealing wire may be inserted through one set of the apertures, guided through the passageway and passed out through the other set of the apertures.

Publication JP 2021 137982 discloses a double-sided laminated paper and paper-cup.

SUMMARY AND PRINCIPLE OF THE INVENTION

The invention is in field of packaging and in particular tubular packagings based on biosourced or biodegradable or recyclable materials for preserving dry products. According to a preferred embodiment, the packaging is based on cellulose and can be recycled in the paper industry. The packaging comprises at least one container and a lid which slides over the said container and the packaging retains good moisture-barrier properties throughout its service life.

The invention more specifically relates to a tubular packaging comprising a container and a close-fitting lid that slides over the outer surface of the container over a height referred to as “sealing height”. More specifically, and in some embodiments, the invention relates to a packaging formed by two tubular bodies of slightly different diameters, one of the said bodies forming the container, and the other one of the said bodies forming the lid. According to the invention, the lid has a diameter slightly larger than that of the container and it is push-fitted onto and slides over the outer surface of the container with a clearance necessary for the opening and closing operations. In the closed position of the packaging, the wall of the lid is superposed on the wall of the container over a sealing height which ensures the moisture barrier of the packaging, even after the first opening or subsequent opening of the packaging.

According to the invention, the container and the lid are based on biosourced or biodegradable or recyclable materials and comprise at least one layer providing the moisture-barrier properties.

According to the preferred embodiment of the invention, the container and the lid are based on cellulose and comprise at least one cellulose-based structural layer and one functional layer providing the moisture-barrier properties.

Surprisingly, it has been shown that a cellulose-based tubular packaging formed by a container and a lid which is push-fitted onto and slides over the outer wall of the container according to the principles of the present invention can, in certain conditions explained in the rest of the present description, have identical or even improved barrier properties in relation to the same container were it to be closed by a sealed lid.

More specifically, it has been shown that, to provide the improved barrier properties mentioned above, the radial clearance between the outside diameter of the container and the inside diameter of the lid must be between 0.05 mm and 0.25 mm, and preferably between 0.1 mm and 0.2 mm.

Similarly, it has been shown that the sealing length (that is, the length of the push-fit between the container and the lid) must be greater than 50 mm and preferably greater than 100 mm.

According to the invention, the packaging is based on materials that are recyclable or biodegradable and/or originate from renewable resources.

According to a preferred embodiment of the invention, the packaging is based on cellulose and can be recycled at the end of its life in the paper industry. Preferably, the cellulose content of the packaging is greater than 85% and advantageously greater than 90%. Preferably, the cellulose content of the packaging and that of the lid are identical or similar. In another embodiment, these contents may be different.

According to the invention, the packaging may also have air inlet and outlet means which make it easier to open and close the packaging. The air inlet and outlet means are advantageously, but not exclusively, linked to the lid.

According to the invention, the packaging may also have tamper-evident means which evidence the first opening of the packaging.

In embodiments, the invention relates to a packaging comprising at least one first body that forms a container and one second body that forms a lid, the container and the lid having moisture-barrier properties at their respective walls, the lid having an inner dimension larger than the outer dimension of the container and sliding over at least part of the outer surface of the container, in the process defining a sliding length when the packaging is being opened or closed, the clearance created by the difference in the said dimensions enabling the said opening and the said closing without adversely affecting the moisture-barrier properties of the packaging.

In embodiments, the clearance is preferably between 0.02 mm and 0.5 mm.

In embodiments, a ratio H/D is greater than 1, preferably greater than 2, H being the sliding length and D being the outer dimension of the container.

In embodiments, the container and the lid each comprise an end wall or a bottom.

In embodiments, the container and/or the lid and/or the bottom comprise a structural layer and a functional layer that provide water vapour-barrier properties.

In embodiments, the structural layer is based on cellulose with a cellulose content preferably greater than 70%.

In embodiments, the functional layer is made of high-density polyethylene (HDPE) or polypropylene (PP). Other equivalent materials or blends of materials are possible.

In embodiments, the functional layer that forms the inner surface of the lid slides over the structural layer that forms the outer surface of the container.

In embodiments, the functional layer that forms the inner surface of the lid slides over the functional layer that forms the outer surface of the container.

In embodiments, the structural layer of the container is trapped between a first functional layer that forms the outer surface of the container and a second functional layer that forms the inner surface of the container.

In embodiments, the lid comprises a flared end for making it easier to insert the lid on the container. In some embodiments, the end of the container on which the lid is push-fitted comprises a narrowing. A flared portion and a narrowing can also be used on one and the same packaging.

In embodiments, the packaging comprises a tamper-evident system evidencing that the packaging has been opened, for example the first time the packaging is opened.

In embodiments, the packaging comprises a membrane seal secured to the end of the container. The membrane seal can form a tamper-evident system or be part of one.

In embodiments, the packaging comprises air outlet or air inlet means for making it easier to open and close the packaging.

In embodiments, the packaging has a circular, oval, oblong or rectangular cross section. Of course, other shapes are possible.

In embodiments, the container and/or the lid are formed from tubular bodies (or bodies of another shape) fabricated from a sheet, the ends/edges of which are welded or adhesively bonded and form a joining zone.

In embodiments, the ends/edges of the sheet are butt-welded via reinforcing strips, or welded or adhesively bonded by overlapping the ends/edges.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 12 illustrate the invention relating to a moisture-barrier packaging having a sliding lid.

FIG. 1 illustrates the concept of the invention.

FIGS. 3 to 5 illustrate the sliding zone between the container and the lid.

FIG. 3 illustrates a first example of the sliding zone in which the functional layer of the lid slides over the structural layer of the container.

FIG. 4 illustrates a second example of the sliding zone.

FIG. 5 illustrates a third example of the sliding zone.

FIG. 6 illustrates an example of the fabrication of a tubular body for a container or an end wall.

FIGS. 7 to 9 illustrate examples of the joining of the end wall to the tubular body for the container or for the lid.

FIG. 7 illustrates the joining of the inner layer of the tubular body to the outer face of the lid.

FIG. 8 illustrates the joining of the outer layer of the tubular body to the inner layer of the end wall.

FIG. 9 illustrates the joining of the inner layer of the tubular body to the inner layer of the end wall.

FIG. 10 illustrates a flared end of the lid for making it easier to insert the lid on the container.

FIG. 11 illustrates the packaging according to the invention with air outlet means in the lid for making it easier to open and close the packaging.

FIG. 12 illustrates the comparison of the water vapour-barrier properties of packagings produced according to the invention with those of a packaging with a sealed lid.

DETAILED DESCRIPTION

• • 1: packaging
  • 2: tubular body forming a container
  • 3: tubular body forming a sliding lid
  • 4: tamper-evident system
  • 5: sliding length
  • 6: tubular wall of the container
  • 6a: structural layer
  • 6b: functional layer
  • 6c: functional layer
  • 7: end wall/bottom of the container
  • 7a: structural layer
  • 7b: functional layer
  • 8: tubular wall of the lid
  • 8a: structural layer
  • 8b: functional layer
  • 9: end wall/bottom of the lid
  • 9a: structural layer
  • 9b: functional layer
  • 10: sliding zone
  • 11: membrane seal
  • 12: sheet joining zone
  • 13: air outlet means
  • 14: flared end

FIG. 1 illustrates an exemplary embodiment of a packaging having water vapour-barrier properties according to the invention. The packaging 1 comprises a tubular body 2 that forms a container and is closed by a lid 3 that slides over the outer surface of the said container 2. The container 2 and the lid 3 have moisture-barrier properties at their respective walls. The lid 3 is superposed on the container 2 over part of the height of the tubular body 2 in order to obtain water vapour-barrier properties for the packaging 1. The inner dimension of the lid 3, such as its diameter, is larger than the outer dimension of the container 2, for example as its diameter, such that the clearance formed by the difference in dimensions, for example in diameters, makes it possible to open and close the lid without adversely affecting the moisture-barrier properties of the packaging. The packaging 1 may comprise a tamper-evident indicator 4 evidencing the first time the packaging 1 is opened. An example of a tamper-evident indicator 4 is a label that is adhesively bonded or welded between parts of the packaging 1 and that is ripped or torn off when the said packaging 1 is being opened.

FIG. 2 illustrates the sectional view of an embodiment of the packaging 1 according to the invention. The container 2 comprises a tubular wall 6 and an end wall or bottom 7. The tubular wall 6 has a geometry which is preferably cylindrical but numerous other geometries can be envisaged within the scope of the present invention, such as tubular bodies with an oval or rectangular cross section or other cross section, such as oblong etc. As will be explained in the rest of the summary of the invention, the end wall 7 is preferably secured to the tubular wall 6 by welding or adhesive bonding. The lid 3 is similar to the container composed of a tubular wall 8 and of an end wall or bottom 9 secured to the tubular wall 8 by welding or adhesive bonding. The sectional view of the packaging 1 illustrated in FIG. 2 shows the sliding length 5 of the tubular wall 8 of the lid and of the tubular wall 6 of the container. FIG. 2 does not show the functional clearance between the inner side of the wall 8 of the lid 3 and the outer side of the wall 6 of the container 2 that is necessary for the push-fitting of the lid and the sliding of the lid while the packaging is being opened or closed. A detailed view of the sliding zone 10 between the lid 3 and the container 2 is illustrated in FIGS. 3 to 5. FIG. 2 illustrates an embodiment with a membrane seal 11 (which is optional) that is welded to the end of the wall 6 of the container 2 and can serve as tamper-evident indicator (instead of the label 4 illustrated in FIG. 1 or in addition to the said label 4) and can also improve the impermeability of the packaging 1 to water vapour before it is opened for the first time.

According to a preferred embodiment of the invention, the examples of the packaging 1 that are illustrated in FIGS. 1 and 2 are based on cellulose with a cellulose content greater than 70%, preferably greater than 85% and advantageously greater than 90% and can consequently be recycled in the paper industry.

The cellulose-based packaging 1 according to the invention and that is formed by a container 2 and a sliding lid 3 was compared to a packaging formed by the container 2, the end of which is closed by welding on a moisture-tight membrane seal. Surprisingly, it was determined that, in spite of the clearance between the lid and the container, which makes the packaging not air-tight, such a packaging according to the invention has, under certain conditions, equivalent or even improved water vapour-barrier properties in relation to the entirely sealed packaging.

In particular, and in order to realize this improvement, it was determined that the radial clearance between the outer wall of the container 2 and the inner wall of the lid 3 must be between 0.02 mm and 0.5 mm, and preferably between 0.05 mm and 0.25 mm.

Similarly, the ratio H/D, where H is the sliding length and D is the outer dimension of the container 2 (for example its outside diameter) is greater than 1 and preferably greater than 2. If the container 2 and the lid 3 have a cylindrical cross section, the outer dimension of the container 2 and the inner dimension of the lid 3 correspond to the respective diameters of the container and of the lid. If the container 2 and the lid 3 have a non-cylindrical (such as oval, oblong, square, rectangular or other) cross section, an “equivalent cylinder”, the perimeter of which is equal to the perimeter of the cross section (irrespective of its shape) of the said container 2 and of the said lid 3 in question, is defined for the container 2 and the lid 3 and the dimension used is the (outside/inside) diameter of each “equivalent cylinder” determined in this way.

For example, for a container with an outside diameter of 50 mm, the sliding length 5 is greater than 50 mm (ratio H/D=1) and preferably greater than 100 mm (ratio H/D=2).

FIG. 3 illustrates an example of the packaging 1 in the sliding zone 10. The container 2 comprises a wall 6 formed by at least one cellulose-based structural layer 6a and one thin functional layer 6b which provides water vapour-barrier properties. Similarly, the lid 3 comprises a wall 8 formed by at least one cellulose-based structural layer 8a and one thin functional layer 8b which provides moisture-barrier properties. The functional layers 6b and 8b are, for example, made of high-density polyethylene (HDPE) or polypropylene (PP) or other equivalent materials. The thickness of the functional layers 6b and 8b is small enough for the mass fraction of cellulose of the part in question (container 2 or lid 3) to be greater than 70%.

In the embodiment of FIG. 3, the functional layer 8b that forms the inner surface of the tubular body 8 of the lid 3 slides over the cellulose-based structural layer 6a that forms the outer surface of the tubular body 6 of the container 2. A clearance between the layer 8b of the lid and the layer 6a of the container is necessary for easy opening and closing of the container. The magnitudes of this clearance and of the sliding length 5 formed by the superposition of the lid and of the container influence the sealing of the packaging with respect to water vapour. These magnitudes are for example those mentioned above in accordance with the determinations of the present invention.

FIG. 4 illustrates another embodiment of the structure of the packaging in the sliding zone 10. In this embodiment, the functional layer 8b that forms the inner surface of the tubular body 8 of the lid 3 slides over the functional layer 6b that forms the outer surface of the tubular body 6 of the container 2. A clearance between the layer 8b of the lid and the layer 6b of the container is necessary for easy opening and closing of the container. The magnitudes of this clearance and of the sliding height 5 formed by the superposition of the lid and of the container influence the sealing of the packaging with respect to water vapour and are, for example, those mentioned above in accordance with the determinations of the present invention.

FIG. 5 illustrates another embodiment of the structure of the packaging in the sliding zone 10. In this embodiment, the structural layer 6a of the container is trapped between a first functional layer 6b that forms the outer surface and a second functional layer 6c that forms the inner surface of the tubular body of the container 2.

In the embodiment illustrated in FIG. 5, the functional layer 8b that forms the inner surface of the tubular body 8 of the lid 3 slides over the functional layer 6b that forms the outer surface of the tubular body 6 of the container 2. A clearance between the layer 8b of the lid and the layer 6b of the container is necessary for easy opening and closing of the container 6. The magnitudes of this clearance and of the sliding height 5 formed by the superposition of the lid and of the container influence the sealing of the packaging with respect to water vapour and are, for example, those mentioned above in accordance with the determinations of the present invention.

FIG. 6 illustrates a preferred embodiment of the tubular body 6 of the container 2 and that 8 of the lid 3. According to this preferred embodiment, the tubular bodies are fabricated from a sheet, the edges of which are welded or adhesively bonded and form a joining zone 12. Preferably, the ends of the sheet are butt-welded via reinforcing strips, as described in the publications EP2007567, EP2004389, EP2004506 and EP26030052. As an alternative, the edges of the sheet are welded or adhesively bonded by overlapping its ends.

FIGS. 7 to 9 illustrate embodiments of joining a bottom 7 or 9 to a tubular body 6 or 8 to form a container 2 or a lid 3 and also show the continuity of the functional layer 6b/8b/7b/9b in the joining zone for obtaining good barrier properties of the final product.

FIG. 7 illustrates the joining of an end wall 7 to a tubular body 6 in order to form a container 2. In this example, the functional layer 7b of the end wall that forms the outer surface of the container 2 is welded to the functional layer 6b of the tubular body that forms the inner surface of the container 2. FIG. 7 also illustrates the joining of an end wall 9 to a tubular body 8 in order to form a lid 3.

In this example, the functional layer 9b of the end wall that forms the outer surface of the lid 3 is welded to the functional layer 8b of the tubular body that forms the inner surface of the lid 3. Welding the respective functional layers 6b/7b and 8b/9b makes it possible to ensure the continuity of the said functional layers.

FIG. 8 illustrates another embodiment of joining a bottom 7 to a tubular body 6 or 8 in order to form a container 2 or a lid 3. FIG. 8 illustrates the continuity of the functional layers 6b/7b and 8b/9b in the joining zone joining the end wall 7 and the tubular body 6/8 for obtaining good barrier properties of the final product. FIG. 8 illustrates the joining of a bottom 7 to a tubular body 6 in order to form a container 2. In this example, the functional layer 7b of the bottom that forms the inner surface of the container 2 is welded to the functional layer 6b of the tubular body that forms the outer surface of the container 2. FIG. 8 illustrates the joining of bottom 9 to a tubular body 8 in order to form a lid 3. In this example, the functional layer 9b of the bottom that forms the inner surface of the lid 3 is welded to the functional layer 8b of the tubular body that forms the outer surface of the lid 3.

FIG. 9 illustrates another embodiment of joining a bottom to a tubular body in order to form a container 2 or a lid 3. FIG. 9 illustrates the continuity of the functional layer in the joining zone for obtaining good barrier properties of the final product. FIG. 9 illustrates the joining of a bottom 7 to a tubular body 6 in order to form a container 2. In this example, the functional layer 7b of the bottom that forms the inner surface of the container 2 is welded to the functional layer 6b of the tubular body that forms the inner surface of the container 2. FIG. 9 also illustrates the joining of a bottom 9 to a tubular body 8 in order to form a lid 3. In this example, the functional layer 9b of the bottom that forms the inner surface of the lid 3 is welded to the functional layer 8b of the tubular body that forms the inner surface of the lid 3.

FIG. 10 illustrates another embodiment of the packaging in the sliding zone 10. In this example, the lid 3 has a flared end 14 for making it easier to insert the lid 3 on the container 2. In this example, the flared zone (in which the clearance between the inner wall of the lid and the outer wall of the container varies) is not to be taken into account for the purpose of defining the sliding length 5 which ensures good water vapour-barrier properties.

An alternative to the solution illustrated in FIG. 10 for making it easier to insert the lid 3 consists in narrowing the end of the container 2 on which the lid 3 is push-fitted. In another embodiment, it is possible to both flare the lid 3, as illustrated in FIG. 10, and narrow the end of the container 2.

FIG. 11 illustrates the packaging according to the invention having air outlet or air inlet means 13 for making it easier to open and close the packaging. Preferably, these means 13 are added in the lid 3. The means 13 are, for example, a valve that allows air to pass when the difference in pressure between the inside and the outside of the packaging exceeds a threshold value. According to another example, the means 13 are an orifice, closed off by a label that can be repositioned by peeling it off, that the user opens when the packaging is being opened or closed.

FIG. 12 compares the water vapour-barrier properties of the embodiments of packagings produced according to the invention. The barrier properties are determined by measuring the amount of water that enters the packaging, when placed in an environment at 38° C. with 50% humidity, as a function of time. The barrier properties of 5 packagings, respectively denoted “Ech-1” to “Ech-5”, are compared:

• • The packaging denoted “Ech-1” is closed by a welded membrane seal and is used as reference.
  • The packaging denoted “Ech-2” is closed by a lid overlapping the container over a sliding length 5 equal to 150 mm with a radial clearance equal to 0.1 mm.
  • The packaging denoted “Ech-3” is closed by a lid overlapping the container over a sliding length 5 equal to 100 mm with a radial clearance equal to 0.1 mm.
  • The packaging denoted “Ech-4” is closed by a lid overlapping the container over a sliding length 5 equal to 50 mm with a radial clearance equal to 0.1 mm.
  • The packaging denoted “Ech-5” is closed by a lid overlapping the container over a sliding length 5 equal to 10 mm with a radial clearance equal to 0.1 mm.

The packagings compared in FIG. 12 all have a cylindrical container 2 with a diameter D equal to 50 mm and a height equal to 250 mm. These packagings are produced with a multilayer structure as illustrated in FIG. 3. The cellulose-based structural layers of the container 2 and of the lid 3 that are denoted 6a and 8a, respectively, have a mass of 265 g/m² and the polyethylene-based functional layers denoted 6b and 8b, respectively, have a mass of 18 g/m². The cellulose content in these packagings is 93.6%.

The packaging “Ech-1”, which is used as reference, has a permeability to water vapour of 0.129 g/(pack.day.bar).

The packaging “Ech-2”, which corresponds to one embodiment of the invention, has a permeability to water vapour of 0.118 g/(pack.day.bar), that is 91% of the value of the sealed packaging denoted “Ech-1”.

The packaging “Ech-3”, which corresponds to one embodiment of the invention, has a permeability to water vapour of 0.127 g/(pack.day.bar), that is 98% of the value of the sealed packaging denoted “Ech-1”.

The packaging “Ech-4”, which corresponds to one embodiment of the invention, has a permeability to water vapour of 0.142 g/(pack.day.bar), that is 110% of the value of the sealed packaging denoted “Ech-1”.

The packaging “Ech-5”, the sliding length 5 of which is too small (10 mm), has a permeability to water vapour of 0.222 g/(pack.day.bar), that is 172% of the value of the sealed packaging denoted “Ech-1”.

Exemplary embodiments have been described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the systems and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that the systems and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the present invention is defined not solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention. A number of problems with conventional methods and systems are noted herein and the methods and systems disclosed herein may address one or more of these problems. By describing these problems, no admission as to their knowledge in the art is intended. A person having ordinary skill in the art will appreciate that, although certain methods and systems are described herein with several non-limiting embodiments, the scope of the present invention is not so limited. Moreover, while this invention has been described in conjunction with a number of embodiments, it is evident that many alternatives, modifications and variations would be or are apparent to those of ordinary skill in the applicable arts. Accordingly, it is intended to embrace and cover all such alternatives, modifications, equivalents and variations that are within the spirit and scope of this invention.