A Recyclable Moulded Pulp Container

Abstract

A moulded pulp container for food includes a main body formed from a moulded pulp material and a pulp tab portion. The main body includes a base, upstanding walls extending from the base, and an outer edge defining a container having an inner surface and an outer surface. The pulp tab portion is connected to and arranged outboard of the outer edge. The pulp tab portion has an upper surface and a lower surface. A barrier membrane laminated to the inner surface of the container and the upper surface of the pulp tab portion is removable when the pulp tab portion is detached from the main body, such that the barrier membrane remains bonded to both the main body and the pulp tab portion, which enables the barrier membrane to be peeled from the main body by pulling the pulp tab portion.

Claims

1. A moulded pulp container for food comprising: a main body comprising: a base; upstanding walls extending from the base; and an outer edge; wherein the base and upstanding walls define a container having an inner surface and an outer surface; and wherein main body is formed from a moulded pulp material; and a barrier membrane comprising a tab portion extending past the outer edge of the main body; wherein the barrier membrane is bonded to the inner surface of the container; and wherein the tab portion defines a pull tab configured to enable the barrier membrane to be pulled from the main body.

2. The moulded pulp container according to claim 1 further comprising a pulp tab portion extending from the outer edge, wherein a tear seam is formed between the pulp tab portion and the main body.

3. The moulded pulp container according to claim 1, wherein the main body further comprises: an upper rim at the outer edge; and an outer return edge extending vertically downwards from the upper rim; wherein the outer return edge has an inner surface facing the upstanding walls and an outer surface facing outwardly away from the upstanding walls.

4. The moulded pulp container according to claim 3 further comprising a pulp tab portion, wherein the pulp tab portion is connected to and arranged outboard of the outer return edge; and wherein the pulp tab portion has an upper surface, a lower surface, and extends in a substantially horizontal direction relative to a vertical outer return wall of the outer return edge.

5. The moulded pulp container according to claim 4, wherein the tab portion of the barrier membrane is bonded to the upper surface of the pulp tab portion; and wherein the barrier membrane is further bonded to the inner surface of the container and the outer surface of the vertical outer return wall.

6. The moulded pulp container according to claim 5, wherein a tear seam is formed between the pulp tab portion and the vertical outer return wall to enable the pulp tab portion to be detached from the main body; and wherein the barrier membrane is bonded to the main body and the pulp tab portion such that when the pulp tab portion is detached from the main body, the barrier membrane remains bonded to both the main body and the pulp tab portion to enable the barrier membrane to be peeled from the main body by pulling the pulp tab portion.

7. The moulded pulp container according to claim 6, wherein the barrier membrane extends continuously and unbroken across the tear seam.

8. The moulded pulp container according to claim 6, wherein the vertical outer return wall comprises a lower peripheral edge; and wherein the pulp tab portion is arranged at and extends outwardly from the lower peripheral edge.

9. The moulded pulp container according to claim 1, wherein the barrier membrane is a polymer film.

10. The moulded pulp container according to claim 9, wherein the polymer is a plastic.

11. The moulded pulp container according to claim 10, wherein the plastic comprises Polyethylene Terephthalate.

12. The moulded pulp container according to claim 1, wherein the barrier membrane is a waterproof membrane.

13. The moulded pulp container according to claim 2, wherein the main body comprises: an upper rim at the outer edge; and a bonding region extending along the upper rim to which a lidding film is bonded; wherein the pulp tab portion is located outboard of the bonding region.

14. The moulded pulp container according to claim 13, wherein the upper rim defines a first plane and an upper surface of the pulp tab portion defines a second plane that is vertically offset from the first plane.

15. A method of forming a moulded pulp container for food comprising: moulding a main body from a pulp material, the main body comprising a base and upstanding walls extending from the base defining a container having an inner surface and an outer surface; and bonding a barrier membrane to the inner surface of the container such that a tab portion of the barrier membrane extends past an outer edge of the main body to define a pull tab that may be gripped to peel the barrier membrane from the main body.

16. The method according to claim 15, wherein the pulp container further comprises a pulp tab portion extending from the outer edge; and wherein the method further comprises forming a tear seam between the pulp tab portion and the main body.

17. The method according to claim 16, wherein the main body further comprises an upper rim at the outer edge and an outer return edge extending vertically downwards from the upper rim having an inner surface facing the upstanding walls and an outer surface facing outwardly away from the upstanding walls.

18. The method according to claim 17, wherein the pulp tab portion is connected to and arranged outboard of the outer return edge, the pulp tab portion extending in a substantially horizontal direction relative to a vertical outer return wall of the outer return edge, and the pulp tab portion having an upper surface and a lower surface.

19. The method according to claim 18, wherein the tear seam is formed between the pulp tab portion and the vertical outer return wall

20. The method according to claim 19, wherein the tab portion of the barrier membrane is bonded to the upper surface of the pulp tab portion; and wherein the barrier membrane is further bonded to the inner surface of the container and the outer surface of the vertical outer return wall such that when the pulp tab portion is detached from the main body, the barrier membrane remains bonded to both the main body and the pulp tab portion to enable the barrier membrane to be peeled from the main body by pulling the pulp tab portion.

21. The method according to claim 20, wherein forming the tear seam comprises applying a tool to the pulp tab portion in a vertical direction relative to the horizontal direction in which the pulp tab portion extends.

22. The method according to claim 21, wherein the tool is moved vertically into contact with the lower surface of the pulp tab portion; and wherein the tool is selected from the group consisting of a pressing tool and a cutting tool.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0037] The present invention will now be described by way of example only with reference to the following illustrative figures in which:

[0038] FIG. 1 shows a moulded pulp food container according to an embodiment of the present invention;

[0039] FIG. 2 shows a cross sectional view of the container of FIG. 1;

[0040] FIG. 3 shows a moulded pulp food container according to another embodiment of the present invention;

[0041] FIG. 4 shows a moulded pulp food container according to an embodiment of the present invention; and

[0042] FIG. 5 shows a cross sectional view of the container of FIG. 4.

DESCRIPTION OF EMBODIMENTS

[0043] Referring to FIG. 1, there is provided a food container for containing food to be heated or served hot. The food container 1 comprises a main body 2 having a base 3 and a plurality of upstanding walls 4 defining an enclosure 6. The walls 4 include side walls 8 and end walls 10. The walls 4 include an upper edge 12. A flange section extends outwardly from the upper edge 12 defining an outwardly extending peripheral rim or lip 14. The lip 14 includes an upwardly facing planar surface 16 and a lower surface 18.

[0044] The main body 2 is formed of a moulded pulp material, which may be formed from any suitable recyclable pulp material. The main body 2 may be formed by any suitable pulp moulding technique, including transfer moulding or thermoforming. Preferably the main body 2 is thermoformed, providing the surface of the body 2 with a smooth finish.

[0045] The main body 2 comprises an inner surface 20 and an outer surface 22. As shown in FIG. 2, a layer of plastic 24 is provided on the inner surface 20 of the main body 2 that forms a barrier membrane, which may for example be a waterproof membrane. The barrier membrane 24 may be formed from any plastic material suitable for forming as a thin film and bonding to a pulp material. The barrier membrane preferably comprises a polymer able to withstand temperatures of over 150° C. and preferably over 200° C. For this reason, the barrier membrane 24 may be formed from Polyethylene Terephthalate (PET) or a similar material. The thin film of PET is laminated onto the inner surface 20 of the main body 2 to form the barrier membrane 24. The lamination process bonds the barrier membrane 24 to the inner surface 20. The lamination process comprises heating the thin film of PET or other plastic and drawing the heated plastic film onto the inner surface 20 of the main body 2 using a vacuum applied at the outer surface 22. The plastic film is subsequently trimmed to remove any excess plastic surrounding the container 1.

[0046] The barrier membrane 24 covers the inner surfaces of the base 3 and side walls 4, and also extends over and covers the upper surface 16 of the lip 14. The laminated bonding between the upper surface 20 of the main body 2 and the barrier membrane 24 is such that the barrier membrane 24 may be peeled away from the inner surface 20 of the main body 2 with the application of a suitable mechanical force. However, in order to do so a person must be able to grip the barrier membrane 24 to apply the required force.

[0047] A tab 26 extends outwardly from the peripheral edge 28 of the lip 14. The tab 26 is sized and shaped to enable it to be gripped by a user between the thumb and forefinger. The tab 26 may be substantially semi-circular, square, rectangular, triangular or any suitable shape. The tab 26 is formed as part of the main body 2 and is integrally moulded with the main body 2. The shape of the tab 26 may be formed in a post moulding trimming or die cutting stage, or by any suitable means.

[0048] A tear seam 32 is created between the tab portion 26 and the main body 2. The barrier membrane 24 extends over the tear seam 32 and a tab portion 34 of the barrier membrane 24 is bonded to the upper surface 30 of the tab 26, which is coplanar and contiguous with the upper surface 16 of the lip 14. As such a continuous membrane extends across the main body 2 and the tab 26. The tab 26 is frangible and may be torn or otherwise detached from the lip 14 of the main body 2. The tear sear 32 formed between the tab 26 and the lip 14 is aligned with the peripheral edge 28 of the lip 14. In the embodiment shown in FIG. 2 the tear seam 32 is formed by a die cut linear region of reduced thickness in the pulp material extending along the boundary line between the inner edge 36 of the tab 26 and the outer peripheral edge 28 of the lip 14. Alternatively, the tear seam 32 may be formed by a series of perforations or any other means of mechanical weakening of the pulp material along the tear seam 32. The tear seam 32 may be formed by a punching, scoring, cutting or any other suitable means. Alternatively, the tear seam 32 may be formed during moulding. The tear seam 32 is formed in the pulp material of the tab 26 only, and the barrier membrane 24 extends continuously over the tear seam 32 in an unbroken manner with no reduction in thickness or strength.

[0049] In an alternative embodiment shown in FIG. 3, the tab 126 is formed within the boundary of the peripheral edge 128 of the lip 114. As such the tab 126 extends inwardly from the peripheral edge 128 of the lip 114. The tear seam 132 extends through a section of the lip 114, defining a boundary between the lip 114 and the tab 126, with the tab 126 being a removable portion of the lip 114. In a similar manner to the first embodiment, the barrier membrane 24 extends across the tear seam 132 and a tab portion 134 is bonded to the upper surface of the tab 126.

[0050] In use the container 1 is filled with a quantity of food and a plastic cover film is applied to the container 1 to cover and seal the enclosure 6. The plastic cover film (not shown) is bonded to the container 1 along the upper surface 22 of the lip 14. The plastic cover film is bonded to the region of plastic membrane 24 covering the lip 14 by heat sealing or other means in such a manner that the plastic cover film is able to be peeled away from the lip 14 without removing or damaging the plastic membrane 24. At the point of disposal of the container 1 the user is able to remove the barrier membrane 24 by gripping the tab 26 in one hand and the main body of the container in the other and pulling the tab 26 substantially upwardly away from the lip 14. As the tab 26 is pulled in this manner the tear seam 32 in the pulp material is broken and the tab 26 tears away from the peripheral edge 28 of the main body 2. However, the barrier membrane 24 remains intact and does not tear along the tear seam 32. At this point the barrier membrane 24 is bonded to both the tab 26 and the main body 2. The tab 26 is detached from the main body 2 but remains connected thereto by the barrier membrane 24.

[0051] As the user continues to pull the tab 26, including the tab portion 34 of the barrier membrane 24, the barrier membrane 24 is peeled away from the inner surface 22 of the main body 22. The user continues to pull until the entire barrier membrane 24 has been detached from the main body 2 with only the tab 26 remaining bonded to the barrier membrane 24. The user may then dispose of the main body 2 and barrier membrane 24 as separate elements. As such, the container 1 is received at the recycling station without the plastic barrier membrane 24 and may be processed without the requirement to remove the plastic at any stage. Although it is possible that certain users may forget or decide not to remove the plastic barrier membrane 24, the overall proportion of plastic present in the macerated slurry will be reduced if a percentage of users act responsibly and follow the recycling directions by removing the barrier membrane 24 when disposing of the container 1.

[0052] In the embodiment of FIG. 4, the food container 100 comprises a main body 102 formed of a pulp material having a base 103 and a plurality of upstanding walls 104 defining an enclosure 106. The walls 104 include side walls 108 and end walls 110. The walls 104 include an upper edge 112 with a flange section 114 extending outwardly from the upper edge 12 defining an outwardly extending peripheral lip having an upwardly facing planar surface 116. A vertical outer wall 118 extends downwardly from the outer edge of the flange 114 to create a return edge. The outer wall 118 terminates at a lower edge 120. The return edge created by the vertical outer wall 118 increases the strength of the upper rim of the container 100.

[0053] The main body 102 comprises an inner surface 121 and an outer surface 122. As shown in FIG. 4, a layer of plastic 124 is provided on the inner surface 121 of the main body 102 that forms a thin barrier membrane, as described above. The layer of plastic 124 is laminated onto and bonded to the inner surface 121 of the main body 2 to form the barrier membrane 124. The barrier membrane 124 covers the inner surfaces of the base 103 and side walls 104, and also extends over and covers the upper surface 116 of the flange 114 and the outer surface 125 of the vertical outer wall 118.

[0054] A tab 126 extends horizontally outwards from, and outboard of, the lower end 120 of the vertical side wall 118. The tab 126 is sized and shaped to enable it to be gripped by a user between the thumb and forefinger. The tab 126 may be substantially semi-circular, square, rectangular, triangular or any suitable shape. The tab 126 is formed as part of the main body 102 and is integrally moulded with the main body 102. The shape of the tab 126 may be formed in a post moulding trimming or die cutting stage, or by any suitable means. As the tab 126 projects horizontally outwards from the vertical wall, it is able to be trimmed or cut in a vertical cutting operation.

[0055] A tear seam 132 is created along the tab 126, between the tab 126 and the outer wall 118. The tear seam 32 may be a linear region of reduced thickness in the pulp material extending along the boundary line between the inner edge of the tab 126 and the outer peripheral edge of the outer wall 118. Alternatively, the tear seam 132 may be formed by a cut, series of perforations or any other means of mechanical weakening of the pulp material along the tear seam 132. The tear seam 132 may be formed by punching, scoring, cutting or any other suitable means. These operations are performed vertically on the tab 126, which extends horizontally away from the vertical outer wall 118, having an outer edge 138 that is horizontally outboard of the outer surface 136 of the outer wall 118. Following lamination of the container 100, the container 100 is inverted and a cutting tool is brought vertically downwards into engagement with the lower surface of the tab 126. The blade of the cutting tool is configured and arranged to partially cut through the tab 126, thereby creating a weakened region defining the tear seam. It would not be possible to perform these operations in a horizontal direction, as would be required if the tab 132 were to extend vertical downwards from the end of the vertical outer wall 118, as the cutting process requires a support surface to be located on the opposing side of the material being cut. The cutting process must also be conducted in a single direction, in a single plane, whereas cutting horizontally around the periphery of the container would require cutting through 360 degrees.

[0056] The tear seam 132 is formed in the pulp material of the tab 126 only, and the barrier membrane 124 preferably extends continuously over the tear seam 132 in an unbroken manner with no reduction in thickness or strength. The barrier membrane 124 extends over the tear seam 132 and a tab portion 134 of the barrier membrane 124 is bonded to the upper surface 130 of the tab 126, which is vertically spaced below the upper surface 116 of the flange 114. The tab 126 is frangible and may be torn or otherwise detached from its connection with the vertical outer wall 118 along the tear seam 132.

[0057] In use the plastic cover film is bonded to the container 100 along a bonding region extending along the upper rim defined by the upper surface 116 of the flange 114. In containers having a flange at the upper edge, where the laminate film extends to and terminates at the outer edge of the flange, the plastic cover film and the laminate film are bonded together at a common outer edge, or close thereto, and in the same plane. It has been found in such arrangements that when the plastic cover film is removed, the bond between the cover film and the laminate layer causes a peeling force to be applied directly to the outer edge of the laminate layer, at the outer edge of the flange. The strength of the bond between the plastic layer and the laminate layer is such that, rather than the plastic film peeling away from the laminate layer, the two remain bonded and the laminate layer is peeled away from the pulp container together with the lidding film. As a result, the food remains within a sealed plastic pouch formed by the plastic cover and the laminate layer, that is separated from the pulp container. Such an arrangement is clearly not desirable.

[0058] The return edge formed by the vertical outer wall 18 extends the outer edge of the laminate layer 124 away from the upper surface 116 of the flange and the bonding region between the plastic cover layer and the laminate layer 124. Therefore, the peeling force applied to the laminate layer 124 when the plastic cover is removed is inwardly and vertically offset from the outer edge of the laminate layer 124 and the peripheral bonding region between the laminate layer 124 and the main body 102 and in a plane perpendicular to the bonding between the barrier layer 124 and the outer wall 118. Therefore, there is no direct force applied to the outer region of edge bonding between the main body 102 and the barrier membrane 124 and the peeling force form the plastic cover layer is perpendicular to the plane of the required peeling force at the outer edge, and as such the plastic layer is able to be easily and safely removed without any debonding between the main body 102 and the laminate layer 124.

[0059] To remove the laminate barrier membrane 124 the user grips the tab 126 and pulls the tab 126 substantially upwardly and outwardly away from the outer wall 118. As the tab 26 is pulled the tear seam 132 in the pulp material is broken and the tab 126 tears away from the outer wall 118. The laminate barrier membrane 124 does not tear along the tear seam 32 and the tab section 134 remains attached to the rest of the barrier membrane 124. The tab 126 is detached from the main body 102 but remains connected to the barrier membrane 124, which is bonded to both the tab 126 and the main body 102. The barrier membrane 124 is therefore peeled away from the inner surface of the main body 102 as the user continues to pull the tab 126, until the entire barrier membrane 124 has been detached from the main body 102 with only the tab 126 remaining bonded to the barrier membrane 124.