NL2029392B1 - Packaging unit from a moulded pulp material with a self-aligning element and method for manufacturing such packaging unit - Google Patents

Abstract

The present invention relates to a packaging unit from a moulded pulp material, a method for packing products, and a method for manufacturing such packaging units. The packaging unit 5 comprises: — a bottom part with product receiving compartments for holding respective products, with the bottom part at least having a bottom front, a bottom surface, and two bottom sides, — a cover part at least having a cover front, a cover top, and two cover sides, 10 — a hinge-element for hingedly connecting the cover and bottom parts, and — a lock for locking the bottom and cover parts in a closed position of the packaging unit, and wherein the bottom side and cover side comprise a side edge having a self-aligning element.

Description

PACKAGING UNIT FROM A MOULDED PULP MATERIAL WITH A SELF-ALIGNING

ELEMENT AND METHOD FOR MANUFACTURING SUCH PACKAGING UNIT The present invention relates to a packaging unit that is made of a moulded pulp material. These packaging units are used for storing, transporting and/or displaying products like eggs. Packaging units for eggs, such as egg cases, containers or cartons, are known in practice and are generally manufactured from a moulded pulp material that originates from cellulose fibres. Such packaging units comprise a bottom part that is provided with compartments for individual products, and a cover part that is often hingedly connected to the bottom part. The products, such as eggs, are stored. transported and displayed in these packaging units. An example of such egg case is shown in WO 2015/160248 A1 that shows a packaging unit comprising bottom and cover parts that are hingedly connected and that further comprises a lock that is configured for locking the cover part and the bottom part in a closed position of the packaging unit.

In the handling of such packaging units forces act on all sides of the packaging unit, including the back side of the packaging unit that is often provided with a hinge. This may result in the cover part moving relatively to the bottom part. In case the cover part moves forward relative to the bottom part this may result in unlocking of the packaging unit as the opening in the cover part disengages from the locking cam in the bottom part. For example, this may occur when transporting packaging units filled with products in an automated packer line. Such situations may cause damage to the product, packaging unit and/or a standstill of the packer line. In case of so- called flapless designs of the packaging unit this effect occurs more often as the products do not “push” the flap in the forward direction to compensate (part of) the undesired relative movement between cover and bottom parts of the packaging unit.

The present invention has for its object to obviate or at least reduce one or more of the above stated problems with conventional packaging units, such as egg cases, and to provide a suitable packaging unit enabling convenient display of products.

The present invention provides for this purpose a packaging unit from a moulded pulp material, wherein the packaging unit according to the present invention comprising: — a bottom part with product receiving compartments for holding respective products, with the bottom part at least having a bottom front, a bottom surface, and two bottom sides: — a cover part at least having a cover front, cover top, and two cover sides; — a hinge-clement for hingedly connecting the cover and bottom parts; and — alock for locking the bottom and cover parts in a closed position of the packaging unit, and wherein the bottom side and cover side comprise a side edge having a self-aligning element.

The packaging unit according to the invention is manufactured from a moulded pulp material that may originate from soft wood fibres and/or hard wood fibres and/or recycled cellulose fibres and/or other suitable fibres. The packaging unit comprises a bottom part and a cover part that are hingedly connected to each other with a hinge-element, such as a hinge. The bottom part and cover part of the packaging unit each comprise a front surface, a back surface, and two side surfaces. In addition, the bottom part comprises a bottom surface and the cover part comprises a top surface.

The bottom part is provided with product holding compartments that are capable of receiving and holding respective products, such as eggs, and also similar products like kiwis and tomatoes, for example. Preferably, between adjacent compartments one or more cones are provided to give additional support to the packaging unit.

Furthermore, the packaging unit preferably comprises a lock that is configured for locking the bottom and cover parts in a closed position of the packaging unit. In a presently preferred embodiment the lock comprises a first locking element in the bottom part, such as a cam element, and a second locking element in the cover part, such as an opening. In a closed position the locking elements engage such that the opening is positioned over the locking cam, for example.

In a closed position of the packaging unit the side edges of the cover part and bottom part engage each other. More specifically, the side edge of the cover part rests on the side edge of the bottom part. According to the invention, the side edge comprises a self-aligning element. Such self-aligning element may involve a specifically shaped or formed element that allows such self- aligning effect.

When loads or forces act on the cover top of the cover part in a closed position of the packaging unit, the cover part is pushed (further) over or against the bottom part and the effect of self-alignment between cover and bottom parts is further enhanced. This even better guarantees a correct and optimal positioning of the cover part relative to the bottom part. This reduces the risk of product damage, damage to the packaging unit, and stand-still periods of an automated packer line, for example.

In addition, it was shown that the self-aligning element provides additional support against relative movement between cover and bottom part in a substantial horizontally direction, or in other words in a direction or plane that is substantially parallel to the cover top surface. This effectively prevents an opening in the cover part moving over the locking cam element in the bottom part resulting in an undesired opening of the packaging unit. This holds for different designs of the packaging unit, including a so-called flapless design of the packaging unit. As mentioned earlier, in a flapless design the flap with the locking cam element is not being pushed forward together with the cover part by the products to compensate at least a part of the relative movement between cover and bottom parts. In fact, the effect of the self-aligning element improves both flapless packaging unit and packaging units with flap. An advantage of the self-aligning element is the improved stability, also when being moved on an automated packing line. Typically, when a packaging unit is stopped on the packing line, a next packaging unit comes at speed to a stop with the rear against the other packaging unit. The self-aligning element is preventing the cover part/lid from moving forward and in this way prevents the opening/closing holes to move over the closing nocks/cams, which in turn will allow the packaging unit to unintentionally open on an inconvenient place. Therefore. the self-aligning element may prevent damage to the product, packaging unit and/or a standstill of the packing line. This self-aligning element appears especially advantageous for so-called flapless designs of the packaging unit.

As a further effect of the packaging unit according to the present invention the stability of bundles of packaging units during transport and storage is significantly improved. In transport and storage the packaging units are often packed in bundles that are often positioned on their side edges. Providing the side edge with a self-aligning element changes the shape of such edge from a straight or substantially straight line to a shaped edge that is more stable when being positioned on this side edge. This improves storage and transport, and reduces the risk of damaging the side edge of the packaging units during transport and storage.

The self-aligning element is shaped or formed to enable a self-aligning effect when placing the cover part on top of the bottom part of the packaging unit. Numerous shapes for this element can be applied, including circular shape, saw tooth shape, semi-circular shape, triangular/tooth shape, and other suitable shapes. As an even further effect of the self-aligning element the strength of the packaging unit is further increased. This is achieved by better securing the position of the cover part relative to the bottom part in the closed position of the packaging unit. Furthermore, the self-aligning element prevents this location of the cover part relative to the bottom part especially in the horizontal direction such that the strength and stability of the packaging unit is being maintained also in case of forces or loads acting on the packaging unit. Furthermore, the self-aligning element provides somewhat more moulded pulp material at specific positions of the packaging unit. This additional material contributes to the overall strength and stability of the packaging unit. This improvement in strength of the packaging unit becomes more and more relevant as fibre material originating from recycled paper has shorter fibre lengths. These shorter fibres decrease the strength of the packaging unit. Therefor, the provision of a self-aligning element may counteract this loss of strength due to the decrease in fibre lengths, especially when working with recycled paper material. Tests have been performed that show that in case of a load of 30-40 kg acting on the top surface of the packaging unit can be handled, while a similar conventional (flapless) packaging unit collapses.

In a presently preferred embodiment the self-aligning element is substantially positioned in the front half of the side edge as seen in a closed position of the packaging unit.

This front half of the side edge relates to the front half of the cover and bottom parts towards the front thereof in the closed position of the packaging unit. This specific position of the self-aligning element improves the fixation of the cover and bottom parts in the closed position of the packaging unit, thereby further reducing the risk of undesired or unintended opening of the packaging unit.

In a presently preferred embodiment the self-aligning element comprises a smooth curvature.

A smooth curvature may relate to a smoothened semi-circle or a type of smoothed bump that is provided in an either upward or downward direction as seen in the closed position of the packaging unit. Such smoothed shape prevents sharp edges on the side edge as seen in a back to front direction of the packaging unit. An advantage thereof is that such smoothed curvature is more easily maintained in time, even in case of repeatedly opening and closing the packaging unit. Sharp edges are often damaged and that may result in a less functional packaging unit. Preferably, the self-aligning element is provided with a wave-shape. Such smooth wave-shaped curvature provides a functional packaging unit, wherein the wave-shape further enhances the visual effect corresponding to the shape of the products that are intended to be put into the packaging unit. Also, the wave-shape provides a smooth closure of the packaging unit, even in presence of disturbing forces acting on the packaging unit. Even further, the wave-shape minimizes, and even obviates, the risk of unprecise and/or incorrect closure of the packaging unit when being handled, for example when filling the packaging unit with products. This further reduces the risk of product loss or product damage.

In a presently preferred embodiment the packaging unit is provided with a so-called elevated hinge. Such elevated hinge provides the packaging unit with more stability, especially in an automated packer line. In an embodiment of the invention that is provided with such elevated hinge the side edges of the bottom and cover parts are effectively inclined in a downwards direction in a closed position of the packaging unit when seen in up back to front direction.

The elevated hinge connects the bottom and cover parts of the packaging unit, preferably at the rear side of the packaging unit. Providing the hinge between bottom and cover parts as an elevated hinge positions the hinge higher from the ground surface. This enables providing the front surface of the cover part as extending below the elevated hinge of an adjacent packaging unit. This reduces the required space for two or more packaging units placed adjacent to each other. This is also beneficial in a packing operation in case grippers and vacuum heads grip and pickup several packaging units at once. This improves the efficiency of the packing operation. Preferably, the hinge width is reduced as compared to a conventional hinge width. This contributes to an overall reduction in size and improved packing operation. Furthermore, the combination of the elevated hinge and the self-aligning element further improves the self-aligning etfect as the elevated hinge 5 enhances the closure of the self-aligning element.

In a presently preferred embodiment of the invention the side edges of the cover and/or bottom parts comprise at least one denesting support part, and wherein the at least one denesting support part is within a distance of 20% of the total length of the side edge in a back to front direction from the cover and bottom fronts.

Providing a denesting support part contributes to the overall strength of the packaging unit. By providing more moulded pulp material the strength is improved. The denesting support part assists in denesting packaging units from a stack. In an automated packer line the front of the denesting part is often most important. By positioning the denesting support part at a distance from the front surface(s) of about 20% of the total length of the side edge(s), the denesting support part improves denesting and, in addition, contributes to the strength and stability of the packaging unit at a relatively important position close to the comer of the packaging unit. Preferably, the location of a denesting support part at least partially overlaps with the self-aligning element. This further improves the strength and stability of the packaging unit and also better maintains the overall shape of the packaging unit.

Preferably, the denesting support part comprises a bottom and cover support part that are provided on the bottom and cover parts, respectively, and engage each other in a closed position of the packaging unit to form the denesting support part. More preferably, each side of the packaging unit is provided with two denesting support parts, one denesting support part positioned towards the front of the packaging unit and one denesting support part positioned towards the back of the packaging unit as seen in a back to front direction. The one or more denesting support parts contribute to the fixation of the cover part especially in the comers of the packaging unit, thereby contributing to the overall support.

Preferably, in case two or more denesting support parts are provided, these parts are also preferably provided within the aforementioned range of 20% distance from either the front or back ofthe packaging unit. More preferably, the denesting support elements are provided within a range of 15% of the total length of the side edge from the cover and/or bottom fronts.

In a presently preferred embodiment of the invention the cover and bottom sides comprise one or more ribs that substantially extend from the top surface of the cover part in the direction of the bottom surface, and wherein the ribs protrude from the side surface and provide the cover and bottom parts with additional support when stacking a number of packaging units.

Providing the ribs substantially extending in a vertical direction from the top surface to the bottom surface improves the strength of the packaging unit of the invention. This is especially useful in a stack of packaging unit that are often crosswise stacked. The ribs significantly improve the stability of such stack.

The provision of the self-alignmg element in the side edge of the packaging unit according to the invention better fixates the relative position of the cover and bottom parts. This also better aligns the ribs of bottom and cover parts within one packaging unit and between different packaging units in a stack. This better guarantees the stability of such stack during the transport, for example.

Preferably, the ribs are provided with substantially straight edges to provide strength and stability, and also the transmission of forces acting on a packaging unit, for example in a stack of packaging units. Optionally, these edges extend under a relatively small angle relative to the vertical as seen in the back to front direction. This may further improve the transmission of forces under specific conditions. Furthermore, the ribs are preferably provided at an angle relative to the vertical together with the side surfaces in a width or left to right direction of the packaging unit, with such angle being about 15°, for example.

Protruding the ribs from the side surfaces and extending the ribs from the top surface to the bottom surface provides additional support surfaces to the top and bottom surfaces of the packaging unit. Providing an additional cover support surface increases the contact surface of the cover part with a bottom part of another packaging unit that is placed on top of the packaging unit. This provides a more stable stack of packaging units. Also, any misalignment of stacked packaging units has lesser impact on the stability of the entire stack. This is also the case when packaging units are stacked crosswise on top of each other. In fact, the combination of such crosswise stacking and providing the additional cover support surface significantly improves the stability of the stack. As a further effect, the improved stability may also increase the strength of the stack as a whole such that stack height can be increased safely. This may render transport and storage more efficient. In a presently preferred embodiment the size of the additional bottom support surface substantially corresponds to the size of the additional cover support surface.

Preferably, the additional cover support surface of one rim has a support surface area of atleast 0.35 cm’. Experiments have shown that an additional support surface area in the range of

0.35 to 2.5 cm? provides good results and an optimal stability of the stacked packaging units.

Also preferably, the rim has an average width of at least 10 mm. By increasing the average width of the rim the strength of the packaging unit is further increased. This contributes to the overall strength of the packaging unit and thereby of a stack of packaging units. Preferably, the average width is in the range of 10 to 30 mm.

Also preferably, the ribs protrude from the side surface of an average distance of at least 3 mm. By protruding the ribs of a certain distance the strength and stability of the packaging unit is improved. Preferably, the ribs protrude from the side surface over an average distance in the range of 3 to 10 mm, more preferably in the range of 4 to 8 mm.

In a presently preferred embodiment of the invention the lock comprises a lock opening and a cam element configured for protruding the lock opening, and wherein the cam element comprises a rib element that substantially protrudes from the cam element in a back to front direction of the packaging unit.

The additional rib element of the locking cam element provides additional stability to this locking cam and also provides additional strength. This also improves the lock stability.

As a further effect the cam element support of the cover part in the closed position of the packaging unit is increased. This further contributes to the lock stability in the closed position of the packaging unit.

In one of the presently preferred embodiments the cam element protrudes through the opening to provide a stable lock. In an alternative embodiment, in a closed position of the packaging unit, the cam element does not protrude fully through the opening and the cam element of the lock substantially lies behind the front plane of the packaging unit. An advantage thereof is that a larger display surface can be provided on the front surface of the packaging unit to enable an improved exchange of information to a consumer, for example.

Preferably, the cam element is provided in a flapless front surface of the bottom part. This has the advantage that no flap is required. This reduces the amount of material that is needed in the manufacturing process of the packaging unit. As an even further effect, the required distance between packaging units in the manufacturing process is reduced such that the overall capacity of the process can be increased. An example of such flapless design is illustrated in NL 2024536.

In a further preferred embodiment of the invention the front surface of the bottom part further comprises a front rib extending over a substantial part of the front edge of the bottom part.

Providing an additional front rib that extends in a substantially horizontal/width direction of the packaging unit significantly improves the strength and stability in both the closed and open positions of the packaging unit. Furthermore, such front rib provides additional strength when the packaging unit is placed in a bundle of packaging units for storage and transport. This significantly reduces the risk of damaging these packaging units.

In a presently preferred embodiment the front rib extends between two adjacent cam elements of the packaging unit. This further improves the rigidity and stability of the front surface of the bottom part.

In one of the presently preferred embodiments the packaging unit is provided with a full front label. Such full front label covers a substantial part of the front surface of the cover part including the lock. This significantly improves the size of the display surface that enables display of information to a consumer. In some of the presently preferred embodiments the full front label comprises a cut for the cam element. Such cut enables a protrusion of the cam element through the lock opening. Such cut in a full front label is preferably a so-called smiley cut that is disclosed in WO 2015/160248 Al.

In a presently preferred embodiment of the invention, the moulded pulp material comprises an amount of natural fibres.

Additionally, or alternatively, the moulded pulp material comprises an amount of a biodegradable material, such as an aliphatic polyester.

The application of natural fibres and/or biodegradable material in a packaging unit from a moulded pulp material is described in WO 2018/067006 Al of the same applicant. Especially the use of wheat straw and/or rapeseed straw showed a relevant effect on the strength and stability of the packaging unit.

The use of natural fibres and/or biodegradable material results in packaging units that are substantially MOSH and/or MOAH free, and/or are (home) compostable. These materials are preferably applied in combination with one or more of the aforementioned features, especially the self-aligning element, one or more denesting support parts, and additional side and/or front ribs. Such combination provides additional strength to the packaging units providing more possibilities to use alternative materials without adversely affecting the behavior of the packaging units.

In a further preferred embodiment of the invention the moulded pulp material comprises an amount of micro fibnillated fibers.

In one of the embodiments of the invention the packaging unit comprises an amount of micro fibrillated cellulose (MFC) fibres. In the context of the present invention this also relates to as nanofibrillar cellulose (NFC) fibres or cellulose nanofibers or nanocellulose. MFC preferably originates from cellulose raw material of plant origin. Presently preferred examples of such plant origin involve the use of sugar beet pulp, sugar cane pulp, and potato pulp.

The use of MFC and/or NFC enhances the fibre-fibre bond strength and further improves the reinforcement effect. Although MFC and/or NFC are preferably applied in combination with one or more of the biodegradable aliphatic polyesters, it is also possible to use MFC and/or NFC as an altemative to these components. In addition, MFC and specifically NFC may even reduce the use of so-called dry strength agents in the moulded pulp material.

In an embodiment of the invention the amount of micro fibrillated fibres is in the range of I to 3 wt% of the moulded pulp material. Experiments showed that such amount already provides an improved strength to the packaging unit and may additionally provide improved properties, for example in view of barrier properties. Barrier properties may include oxygen and/or grease and/or moisture barriers. It is believed that the oxygen barrier properties are achieved by the ability of MFC and/or NFC to form a dense network involving hydrogen bonds, for example.

A further advantage of the use of MFC and/or NFC is the improved printability, including digital printing possibilities. In addition, or as an altemative, MFC may reduce cost by reducing the weight by increasing the amount of fillers. This may also enhance the optical properties.

The present invention further relates to a method for packing products like eggs. comprising the steps of providing a packaging unit in an embodiment of the present invention, and placing therein one or more of the products.

Such method provides the same effects and advantages as described with respect of the packaging unit.

The present invention further relates to a method for manufacturing a packaging unit from a moulded pulp material. the method comprising the steps of: — preparing moulded pulp material; and — providing a packaging unit according to any of the embodiment of the invention.

Such method provides the same effects and advantages as described with respect to the packaging unit.

The methods for packing products and/or manufacturing a packaging unit preferably involve providing a self-aligning element as presented in relation to embodiments of the packaging unit. Such self-aligning clement provides additional support against relative movement between cover and bottom part in a substantial horizontally direction, or in other words in a direction or plane that is substantially parallel to the cover top surface. This effectively prevents an opening in the cover part moving over the locking cam element in the bottom part resulting in an undesired opening of the packaging unit. In addition, the self-aligning element improves storage and transport, and reduces the risk of damaging the side edge of the packaging units during transport and storage. An even further effect of the self-aligning element the strength of the packaging unit is further increased. This is achieved by better securing the position of the cover part relative to the bottom part in the closed position of the packaging unit. Furthermore, the self-aligning element prevents this location of the cover part relative to the bottom part especially in the horizontal direction such that the strength and stability of the packaging unit is being maintained also in case of forces or loads acting on the packaging unit. These effects are further enhanced due to the fact that the self-aligning element provides somewhat more moulded pulp material at specific positions of the packaging unit. The provision of the self-aligning element in the side edge of the packaging unit according to the invention better fixates the relative position of the cover and bottom parts.

This also better aligns the ribs of bottom and cover parts within one packaging unit and between different packaging units in a stack. This better guarantees the stability of such stack during the transport. for example.

Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which: — Figure 1 shows a packaging unit according to the invention in a closed position; — Figure 2 shows the packaging unit of figure 1 in a fully opened position: — Figure 3A shows a front view of the packaging unit of figures 1-2; — Figure 3B shows a top view of the packaging unit of figures 1-2; — Figure 3C shows a side view of the packaging unit of figures 1-2 in a closed position; — Figure 3D shows a bottom view of the packaging unit of figures 1-2; — Figure 4 shows a stack of packaging units according to the invention; — Figure 5 shows a bundle of packaging units according to the present invention, — Figure 6 shows an alternative embodiment of a packaging unit according to the present invention; — Figure 7A-B shows views of an alternative embodiment of a packaging unit according to the present invention; — Figure 8 shows a larger embodiment that is similar to the embodiment shown in figure 7A-B; and — Figures 9 and 10 show views of an alternative embodiment of a packaging unit according to the present invention.

Packaging unit 2 (figures 1-5) comprises flapless bottom part 4 and cover part 6. Bottom part 4 comprises front surface 8, first side surface 10, second side surface 12, back surface 14, and bottom surface 16. Cover part 6 comprises top surface 18, front surface 20, first side surface 22, second side surface 24, and back surface 26. Hinge 28 connects back surfaces 14, 24 of bottom part 4 and cover part 6, respectively. Hinge 28 is located at the rear end of side edge 50 that defines the contact surface of bottom side surfaces 10, 12 with cover side surfaces 22, 24 in a closed position of packaging unit 2. (Elevated) hinge 28 is elevated as compared. to the front end of side edge 50 over height E. In the illustrated embodiment transition region 19 between front surface 20 and top surface 18. This transition region 19 is optional for packaging unit 2.

In a closed position of packaging unit 2 (figures 1 and 3A-D) front surfaces 8, 20 of bottom part 4 and cover part 6 are closed using lock 30. In the illustrated embodiment lock 30 comprises cam element 32 in bottom part 4 and lock opening 34 in cover part 6. In the illustrated embodiment opening 34 extends from front surface 20 into transition region 19, and optionally inwardly extending edge 35 is provided at the lower edge of opening 34. Edge 35 extends between 1 to 3 mm from opening 34, preferably about 2 mm.

Compartments 36 (figure 2) are provided in bottom part 4 and are capable of holding product P, such as an egg. Between compartments 36 there are provided a number of cones 38 that extend upwardly. Optionally, cones 38 are provided with openings or holes (not shown).

Hinge 28 comprises hinge support part 40 that in a closed position of packaging unit 2 engages cover 6 (figure 2 and 3D).

Furthermore, in the illustrated embodiment cam 32 is provided with a top surface 42 (figure 3C and 3D) that engages upper edge or support surface 44 of lock opening 34 in a closed position of packaging unit 2 (figure 1). Above lock opening 34 there is provided indent 46 (figure 2).

As illustrated, cam element 32 (partly) protrudes through opening 34 (figure 3C). Optionally, cam element 32 does not extend beyond cover front surface 20. Preferably, label 48 is provided on cover part 6. Optionally, opening 34 is somewhat wider as compared to cam element 32 to be more “forgiving” when closing packaging unit 2.

Side edge 50 comprises cover side edge 52 and bottom side edge 54 (figures 2 and 3C). Hinge 28 is provided at a first height which is higher as compared to a second height of the front of bottom part 4 with height difference E (figure 3C). Therefore, on average edge 50 inclines downwards in a back to front direction (figure 3C). Edge 50 is provided with self-aligning element 56 (figure 3C) that is provided in the front half of side edge 50 as seen in the back to front direction D. In the illustrated embodiment element 56 is provided as a continuous semi-circle or smoothed bump, and is preferably provided with a wave-shape. In this illustrated embodiment the circle or bump 56 is positioned upwards. It will be understood that, altematively, an upside-down configuration of element 56 can also be envisaged in accordance with the present invention.

Denesting support element 58 (figure 3C) comprises cover support part 60 and bottom support part 62 that engage each other in a closed position of packaging unit 2. It will be understood that denesting support element 58 is optional in all embodiments of the present invention and that it can also be envisaged to only provide cover support part 60 or bottom support part 62. Denesting support part 58 is provided close to the front of edge 50, and in the illustrated embodiment a second denesting support part 64 with cover part 66 and bottom part 68 is provided on edge 50 close to the back of edge 50 as seen in the back to front direction D. in this illustrated embodiment cam 32 is positioned above hinge 28 to further improve the stability of the lock when handling packaging unit 2.

Side rib 70 (figure 3C) comprises cover rib 72 and bottom side rib 74 that are aligned in a closed position of packaging unit 2. Side rib 70 extends from top surface 18 to bottom surface 16 and provides an additional cover support surface 76 (Figures 1 and 3B) and bottom support surface

78 (figure 3D). In the illustrated embodiments ribs 70 comprise straight edges 80 that are provided at an angle « relative to vertical part (figure 3C). Sides 22, 24 of cover part 6 are provided at angle [3 relative to the vertical (figure 3A). In the illustrated embodiment ribs 70 are sharply separated from middle side surface 82. At corners 84 (figure 1) there is provided a transition part between side and front surfaces of packaging unit 2 with a circular shape. Front rib 86 extends between two adjacent cam supports 88 in a substantially horizontal direction (figure 2). Cam element 32 comprises cam ribs 90 that extend in a substantially vertical direction and protrude in back to front direction D (figure 3D).

The moulded pulp material is optionally provided with natural fibres 92 (figure 2) and/or a biodegradable material. Optionally, natural fibres 92 can be allowed to remain visible on packaging unit 2.

Stack 94 (figure 4) of packaging units 2 in a closed position shows in the illustrated embodiment a crosswise stacking with layers 96a,b.c,... Bundle 98 (figure 5) comprises a number of packaging units 2 in a closed position.

Packaging unit 102 (figure 6) comprises flapless bottom part 104 and cover part 106. Bottom part 104 comprises front surface 108, first side surface 110, second side surface 112, back surface 114, and bottom surface 116. Cover part 106 comprises top surface 118, front surface 120. first side surface 122, second side surface 124, and back surface 126. Hinge 128 connects back surfaces 114, 124 of bottom part 104 and cover part 106, respectively. In the illustrated embodiment transition region 119 extends between front surface 120 and top surface 118. This transition region 119 is optional for packaging unit 102. Self-aligning element 56 is provided to packaging unit 102 as described in relation to other embodiments of the invention.

In the illustrated embodiment lock 130 comprises cam element 132 in bottom part 104 and lock opening 134 in cover part 106. In the illustrated embodiment opening 134 is provided in front surface 120 of cover part 106 and extends towards and/or into transition region 119. In the illustrated embodiment opening 134 is provided with support 135. Support 135 rests on cam element 132 in a closed position of packaging unit 102 to provide additional strength and stability. Optionally, recess or notch 137 is provided above support 135 to further improve the locking function of lock 130. It will be understood that dimensions and positions of lock 130 can be designed in accordance to the particular needs of packaging unit 102. For example, locks 130 can be positioned more towards side surfaces 122, 124. Support 135 extends in a front to back direction over a distance preferably between 1 to 8 mm, more preferably between 2 and 6 mm, or another suitable distance.

As indicated in relation to other embodiments of the invention, cam element 132 (partly) protrudes through opening 134. Optionally, cam element 132 does not extend beyond cover front surface 120. Preferably. a label is provided on cover part 106. Optionally, opening 134 is somewhat wider as compared to cam element 132 to be more “forgiving” when closing packaging unit 2. Alternative packaging unit 202 (figure 7A-B) comprises flapless bottom part 204 and cover part 206. Bottom part 204 comprises front surface 208, first side surface 210, second side surface 212, back surface 214, and bottom surface 216. Cover part 206 comprises top surface 218, front surface 220, first side surface 222, second side surface 224, and back surface 226. Elevated hinge 228 connects back surfaces 214, 224 of bottom part 204 and cover part 206, respectively. In the illustrated embodiment transition region 219 extends between front surface 220 and top surface

218. This transition region 219 is optional for packaging unit 202. Self-aligning element 56 is provided to packaging unit 202 as described in relation to other embodiments of the invention. Elevated hinge 228 connects bottom part 204 and cover part 206. In this illustrated embodiment indent 230 is larger as compared to indent 46 (figure 1) to further enhance the locking effect in a closed position of packaging unit 202. In addition, indent 230 extends over substantially the entire height of transition region 219 on front surface 220 of cover part 206 (figure 7A). In this illustrated embodiment edge 244 is larger as compared to edge 44 (figure 1). Alternative packaging unit 302 (figure 8) is provided with 12 compartments and is provided with a design that is closely related to that of packaging unit 202 with 2x6 compartments. Alternative packaging units 402, 502 (figures 9-10) comprise flapless bottom part 404 and cover part 406. Bottom part 404 comprises front surface 408, first side surface 410, second side surface 412, back surface 414, and bottom surface 416. Cover part 406 comprises top surface 418, front surface 420, first side surface 422, second side surface 424, and back surface 426. Elevated hinge 428 connects back surfaces 414, 424 of bottom part 404 and cover part 406, respectively. In the illustrated embodiment transition region 419 extends between front surface 420 and top surface 418. This transition region 419 is optional for packaging unit 402, 502. Self- aligning element 56 is preferably wave-shaped and is provided to packaging unit 402, 502 as described 1n relation to other embodiments of the invention. Also in this embodiment, indent 230 extends over substantially the entire height of transition region 219 on front surface 420 of cover part 406. Packaging unit 502 (figure 10) is provided with an additional shape 504 on at least one, or both, side surfaces 422, 424. In these illustrated embodiments edge 444 is larger as compared to edge 44 (figure 1). Front surfaces 420 of packaging units 402, 502 are larger as compared to front surface 20 of packaging unit 2 (figure 1). In addition, larger front surface 420 of packaging unit 502 is provided with additional wave-shape corner edges 506. Edges 506 provide additional stability when handling packaging units 502, for example in the filling process. In addition. edges 506 enhance the visual effect of wave-shaped self-aligning element 56. In the illustrated embodiment packaging unit 2 comprises a number of product receiving compartments 36 that are provided in two rows of five or six compartments 36. It will be understood that other configurations with a different number of compartments and/or rows can also be envisaged in accordance to the invention.

When manufacturing packaging unit 2 the moulded pulp material is provided to a mould, preferably with the moulded pulp material comprising a number of additives. such as an amount of MFC, NFC and/or AKD, ASA and/or other sizing components. In the illustrated embodiment, packaging unit 2 is moulded in a moulding operation and then dried. The dried packaging units 2 are then used to pack products P by placing one product P in respective compartment 36 to provide a packaging unit that is filled with products P and ready for storage, transport and/or display. Such packaging unit enables a potential buyer to inspect products P while packaging unit 2 remains on the shelf, for example.

Tests with packaging unit 2 on an automated packing line show a significant reduction in problems associated with undesired opening of the packaging unit due to the self-aligning effect. It was shown that line capacity was significantly improved. In addition. due to the stabilising effect of self-aligning element 56, packaging units 2 were less damaged during handling, transport, storage and display.

The present invention is by no means limited to the above-described preferred embodiments thereof. The rights sought are defined by the following claims, within the scope of which many modifications can be envisaged. For example, lock 30 can be provided with differently shaped locking elements. Furthermore, a label can be attached to packaging unit 2, for example a full front label, optionally provided with a smiley cut. The illustrated packaging unit 2 comprises ten product receiving compartments 36. It will be understood that another number of product receiving compartments 36 can also be envisaged in accordance with the invention. Although packaging unit 2 is shown for eggs. it may also be used for other products such as kiwis and tomatoes, for example.

CLAUSES

1. Packaging unit from a moulded pulp material, the packaging unit comprising: — a bottom part with product receiving compartments for holding respective products, with the bottom part at least having a bottom front, a bottom surface, and two bottom sides: — a cover part at least having a cover front, a cover top, and two cover sides; — a hinge-element for hingedly connecting the cover and bottom parts; and — alock for locking the bottom and cover parts in a closed position of the packaging unit, and wherein the bottom side and cover side comprise a side edge having a self-aligning element.

2. Packaging unit according to clause 1. wherein the self-aligning element is substantially I5 positioned in the front half of a side edge in the closed position of the packaging unit.

3. Packaging unit according to clause 1 or 2, wherein the self-aligning element comprises a smooth curvature.

4. Packaging unit according to clause 3, wherein the self-aligning element comprises a wave-shape.

5. Packaging unit according to any of the foregoing clauses, wherein the self-aligning element is configured for preventing or reducing relative movement between cover and bottom parts thereby stabilising the lock and/or fixating the relative position of the cover and bottom parts thereby strengthening the packaging unit.

6. Packaging unit according to any of the foregoing clauses, further comprising an elevated hinge.

7. Packaging unit according to any of the foregoing clauses, wherein the side edges of the cover and/or bottom parts comprise at least one denesting support part, and wherein the at least one denesting support part is located within a distance of 20% of the total length of the side edge from the cover front.

8. Packaging unit according to clause 7, wherein the denesting support part at least partially overlaps with the self-aligning element.

9. Packaging unit according to any of the foregoing clauses, wherein the cover and bottom sides comprise one or more ribs that substantially extend from the cover top surface in the direction of the bottom surface, and wherein the ribs protrude from the side surface and provide the cover and bottom parts with additional support when stacking a number of packaging units.

10. Packaging unit according to clause 9, wherein the ribs extend to the bottom surface and provide the bottom surface with an additional bottom support surface that substantially corresponds to the additional cover support surface.

11. Packaging unit according to clause 10, wherein the additional cover support surface of one rim has a support surface area of at least 0.35 cm?

12. Packaging unit according to clause 9. 10 or 11, wherein the rim has an average width of at least 10 mm.

13. Packaging unit according to any of clauses 9 to 12, wherein the ribs protrude from the side surface over an average distance of at least 3 mm.

14. Packaging unit according to one of the foregoing clauses, wherein the lock comprising a lock opening and a cam element configured for protruding the lock opening, and wherein the cam element comprises a rib element that substantially protrudes from the cam element a back to front direction of the packaging unit.

15. Packaging unit according to clause 14, wherein the cam element is provided on a flapless front surface of the bottom part.

16. Packaging unit according to any of the foregoing clauses, wherein the front surface of the bottom part further comprises a front rib extending over a substantial part of a front edge of the bottom part.

17. Packaging unit according to any of the foregoing clauses, further comprising a full front label.

18. Packaging unit according to clause 17, wherein the full front label comprises a cut for the cam element.

19. Packaging unit according to one of the foregoing clauses, wherein the moulded pulp material comprises an amount of natural fibers.

20. Packaging unit according to one of the foregoing clauses, wherein the moulded pulp material comprises an amount of micro fibrillated fibers.

21. Packaging unit according to clause 20, wherein the amount of microfibrillated fibers is in the range of 1 to 3 wt% of the moulded pulp material.

22. Packaging unit according to any of the foregoing clauses, wherein the moulded pulp material comprises an amount of a biodegradable material.

23. Method for packing products like eggs, comprising the step of providing a packaging unit according to one or more of the foregomg clauses, and placing therein one or more of the products.

24. Method for manufacturing a packaging unit from a moulded pulp material, the method comprising the steps of: — preparing a moulded pulp material; and — providing a packaging unit according to any of clauses 1-22.

Claims (1)

CONCLUSIONS 1. Packaging unit made from a molded pulp material, the packaging unit comprising: — a bottom part with compartments for receiving individual products, the bottom part having at least a bottom front surface, a bottom surface and two bottom sides: — a lid part having at least a lid front surface, lid top surface and two lid sides; - a hinge element for pivotally connecting the lid and the bottom part; and - a closure for closing the bottom and lid parts in a closed position of the packaging unit, and wherein the bottom side and lid side comprise a side edge with a self-aligning element. A packaging unit according to claim 1, wherein the self-aligning element is positioned substantially in the front half of a side edge in the closed position of the packaging unit. 3. A packaging unit according to claim 1 or 2, wherein the self-aligning element comprises a smooth curvature. A packaging unit according to claim 3, wherein the self-aligning element comprises a wave shape. 5. A packaging unit according to any one of the preceding claims, wherein the self-aligning element is aimed at preventing or reducing a relative movement between bottom and lid parts, thereby stabilizing the closure and/or fixing the relative position of the bottom and lid parts therewith. reinforcing the packaging unit. 6. Packaging unit according to one of the preceding claims, further comprising an elevated hinge. A packaging unit according to any one of the preceding claims, wherein the side edges of the lid and/or bottom parts comprise at least one denesting support part, and wherein the at least one denesting support part is located within a distance of 20% of the total length of the side edge from the front of the lid part. A packaging unit according to claim 7, wherein the denesting support part overlaps at least partially with the self-aligning element. A packaging unit according to any one of the preceding claims, wherein the lid and bottom parts comprise one or more ribs which extend substantially from the lid top surface in the direction of the bottom surface, and wherein the ribs protrude from the side surface and the lid and bottom parts of additional support when stacking a number of packaging units. 16. A packaging unit according to claim 9, wherein the ribs extend up to the bottom surface and the bottom surface is provided with an additional bottom supporting surface which substantially corresponds to the additional lid supporting surface. The packaging unit of claim 10, wherein the additional lid support surface of one rib has a support surface area of at least 0.35 cm. A packaging unit according to claim 9, 10 or 11, wherein the rib has an average width of at least 10 mm. A packaging unit according to any one of claims 9-12, wherein the ribs protrude from the side surface over an average distance of at least 3 mm. A packaging unit according to any one of the preceding claims, wherein the closure comprises a closure opening and a cam element adapted to pass through the closure opening, and wherein the cam element comprises a rib element projecting substantially in a rear-to-front direction of the packaging unit. A packaging unit according to claim 14, wherein the cam element is provided on a flapless front surface of the bottom part. A packaging unit according to any one of the preceding claims, wherein the front surface of the bottom part further comprises a front rib extending over a substantial part of a front edge of the bottom part. 17. Packaging unit according to one of the preceding claims, further comprising a full front label. The packaging unit of claim 17, wherein the entire front label includes a cut for the cam element. A packaging unit according to any one of the preceding claims, wherein the molded pulp material comprises an amount of natural fibres. A packaging unit according to any one of the preceding claims, wherein the formed pulp material comprises an amount of fibrillated fibres. A packaging unit according to claim 20, wherein the amount of fibrillated fibers ranges from 1 to 3% by weight of the formed pulp material. A packaging unit according to any one of the preceding claims, wherein the formed pulp material comprises an amount of a biodegradable material. 23. Method for packaging products such as eggs, comprising the step of providing a packaging unit according to one or more of the preceding claims, and placing one or more of the products therein. 24. A method of manufacturing a packaging unit from a molded pulp material, the method comprising the steps of: - preparing a molded pulp material; and - providing a packaging unit according to one of claims 1-22.