Disposable container made of plastic material and packaging method thereof

Abstract

A disposable container (1) made of plastic material comprises: a containment body (8); an access opening (18); an edge wall (20) comprising at least two edge wall portions (33) and at least one connecting portion (50) peripherally interposed between said at least two edge wall portions (33); wherein each edge wall portion (33) comprises: a support rib (40) on which a film may be applied; and a hinge portion (34) interposed between said support rib (40) and said access opening (18), said hinge portion (34) being configured to allow a rotation of said support rib (40); and wherein said at least one connecting portion (50) is configured to allow the support ribs (40) to rotate independently of each other.

Description

[0001] Disposable container made of plastic material and packaging method thereof

[0002] DESCRIPTION

[0003] The present invention relates to the field of packaging of products, for example perishable products, in particular fresh foodstuffs, in disposable packages for retail sale. In particular, the present invention relates to a disposable container made of plastic material and a packaging method thereof.

[0004] Disposable plastic containers are typically produced by means of a moulding technology, e.g. by thermoforming, and are made of a suitable plastic material, e.g. polystyrene, oriented polystyrene, polypropylene, polyethylene terephthalate, polyvinyl chloride, polylactic acid, or bioplastics for example from the Mater-Bi family.

[0005] In order to produce a disposable container by thermoforming, the thermoformable material is typically unwound from a reel in the form of a web and fed into ovens to be heated to a temperature, which varies according to the material and is sufficient to allow the material to be plastically deformed.

[0006] The web is then moulded by plastically deforming it to create the shapes of the containers to be produced. Usually, moulding is carried out by means of pressurised air on one side of the web and vacuum on the opposite side, which deforms the web material inside a mould in which the shapes of the containers to be produced are defined in negative. The number of containers formed at the same time varies, e.g. depending on the size of the container and the size of the machine. At the end of the moulding process, there is a matrix of container shapes joined to one another on the web. Next, the web of thermoformed material with the shapes of the containers arranged in a matrix is cut to separate the individual containers from the scrap. Cutting is carried out either by means of a punch and a punching base around the perimeter of each container shape or by means of blades. The region of the thermoformed material web engaged by the punch during cutting is essentially planar, so that it is properly engaged by the punch or blade, and, following cutting, forms a protruding outer edge.

[0007] A disposable container made as described above comprises a containment body, in which a containment volume is defined. The container has an access opening to the containment volume, and an edge wall extending peripherally around the access opening. The edge wall protrudes outwardly with respect to the containment body until the outer edge produced by the cutting described above.

[0008] The access opening typically has a perimeter of polygonal shape, with a plurality of straight or substantially straight sections and a plurality of non-straight sections, e.g. curved or angled, each placed between two of the aforementioned straight or substantially straight sections. At each straight or substantially straight section of the perimeter of the access opening, the edge wall comprises a respective edge wall portion. At each non-straight section of the perimeter of the access opening, the edge wall comprises a perimeter connecting portion interposed between two of the aforementioned edge wall portions.

[0009] Thermoformed containers made as described above are usually used for the retail sale of perishable food products, e.g. by supermarkets or grocery shops. The product is prepared and placed in the containment volume of the container, which is then closed by wrapping it with a film, e.g. polyvinyl chloride or cellophane or stretchable PE. The function of the film is to protect the product inside the container and to prevent fluids from entering the container and escaping from the container.

[0010] The Applicant has perceived a market need for thermoformed containers made of recycled or more easily recyclable materials.

[0011] The Applicant noted that thermoformed containers made of relatively thick and deformable materials, such as foamy materials like polystyrene, are difficult to recycle. The Applicant has thus perceived an increased demand for more easily recyclable thermoformed containers made of relatively rigid and thin materials such as polyethylene terephthalate.

[0012] The Applicant found that, in thermoformed containers made of this type of relatively rigid and thin material, the outer edge resulting from the above-described punching has a protruding and relatively sharp edge.

[0013] The Applicant has verified that since the outer edge protrudes outwardly, the film wrapped around the container engages it and presses against the sharp edge. This can lead to local tearing of the film wrapped around the container, resulting in unwanted leakage of fluids at the retail stage and possible contamination of the contents and related reduction of shelf life.

[0014] The Applicant found that thermoformed containers made from relatively rigid and thin recycled plastics such as polyethylene terephthalate have an even stiffer and sharper outer edge.

[0015] The Applicant has perceived that if a support rib was provided on each edge wall portion to which the film is applied to close the access opening and a hinge portion configured to allow for rotation of the support rib with respect to the containment body during application of the film, it could result in the displacement of the sharp outer edge to a position that would reduce or eliminate the likelihood of tearing the film.

[0016] The Applicant found that deforming the edge wall so as to move the outer edge inwardly is particularly complex at connecting portions of the edge wall, and that, as a result of deforming the edge wall, the outer edge tends to protrude locally outwardly at non-straight sections.

[0017] The Applicant has also perceived that, during deformation, internal stresses are created in the edge wall in the direction of the perimeter of the access opening due to the stiffness of the material, which tend to be concentrated locally at the connecting portions of the edge wall, counteracting the deformation of the edge wall and causing the outer edge to protrude locally outwardly, making it even sharper.

[0018] The Applicant has found that decoupling the support ribs from each other so that each support rib can rotate about a respective axis of rotation during the deformation of the respective hinge portion independently of the other support ribs would avoid the accumulation of stresses at the connecting portions of the edge wall and the associated effects.

[0019] The Applicant has also found that decoupling the rotations of the support ribs from each other could also lead to advantages during the production of the disposable container that require deformation of the edge wall, for example to temporarily move the outer edge outwardly in order to improve accessibility and thus perform operations on it. The Applicant also perceived that decoupling the rotations of the support ribs from each other is also desirable in single-use containers made with moulding technologies other than thermoforming, such as injection moulding, since the improved deformability of the edge wall at the non-straight sections of the perimeter can help the removal of the container from the moulds.

[0020] The present invention therefore concerns, in a first aspect thereof, a disposable container made of plastic material.

[0021] Preferably, a containment body is provided in which a containment volume is defined.

[0022] Preferably, an access opening to said containment volume is provided, delimited by a perimeter comprising at least two nonstraight sections.

[0023] Preferably, an edge wall is provided, extending from said perimeter to an outer edge of said container.

[0024] Preferably, said edge wall comprises at least two edge wall portions and at least one connecting portion peripherally interposed between said at least two edge wall portions at at least one nonstraight section of the perimeter of the access opening.

[0025] Preferably, each edge wall portion comprises a support rib distal from said access opening and on which a film is applied to close said access opening.

[0026] Preferably, each edge wall portion comprises a hinge portion interposed between said support rib and said access opening.

[0027] Preferably, said hinge portion is configured to allow for rotation of said support rib with respect to said containment body. Preferably, said at least one edge wall connecting portion is configured to allow the support ribs of said at least two edge wall portions to rotate independently of each other about respective axes of rotation.

[0028] Preferably, said respective axes of rotation are substantially parallel to said at least two substantially straight sections of the perimeter of the access opening.

[0029] In a second aspect thereof, the present invention concerns a packaging method.

[0030] Preferably, a container comprising a containment volume in which a containment volume is defined is provided.

[0031] Preferably, a product is to be placed in said containment volume of the container through an access opening to said containment volume, said access opening being delimited by a perimeter comprising at least two substantially straight sections.

[0032] Preferably, a film is to be applied on an edge wall of the container extending from said perimeter of the access opening to an outer edge of said container to cover said access opening.

[0033] Preferably, said edge wall comprises at least two edge wall portions and at least one connecting portion peripherally interposed between said at least two edge wall portions at at least one nonstraight section of the perimeter of the access opening.

[0034] Preferably, each edge wall portion comprises a support rib distal from said access opening and a hinge portion interposed between said support rib and said access opening.

[0035] Preferably, said support ribs of said at least two edge wall portions are rotated with respect to said containment body independently of each other about respective axes of rotation substantially parallel to said at least two substantially straight sections of the perimeter of the access opening.

[0036] The Applicant has found that, at straight or slightly curved portions of the edge wall, each support rib rotates about a respective axis of rotation when pressed during the application of the film. As a consequence, the outer edge that could damage the film is shifted inwardly, and in particular towards the containment body, so that it does not come into contact with the film, or even if it does come into contact, it exerts less pressure against it.

[0037] The Applicant has found that by decoupling the edge wall portions extending along substantially straight sections of the perimeter in such a way that the support ribs can rotate about different axes of rotation independently of each other, the edge wall portions do not deform each other as a result of the rotation of the support ribs. This makes it easier to deform the edge wall and avoids concentrations of stress at the connecting portions.

[0038] In this way, the film can be wrapped around the container without pressing against the outer edge, or pressing against the outer edge with reduced pressure, and the risk of the film tearing due to pressure against the sharp edge of the outer edge is reduced or eliminated.

[0039] The containment body of the disposable container defines a support base. "Support base" refers to one or more parts of the container configured to stably support the container on a horizontal flat surface in a preferred use configuration, with the base of the container in contact with the horizontal flat surface and the access opening facing upwardly.

[0040] The support base of the container defines a support surface, at which the container is in contact with the horizontal flat surface in the preferred use configuration.

[0041] In the present description and in appended claims, "horizontal" means axes, directions, planes or features of the container oriented parallel to the support surface. Similarly, "vertical" means axes, directions, planes or features of the container oriented perpendicular to the support surface.

[0042] In the present description and in the appended claims, expressions referring to a spatial arrangement of one or more features of the container, or to their spatial orientation, as "top", "upper", "upwardly", "bottom", "lower", "downwardly" and the like are to be understood as referring to the container in the above-mentioned preferred configuration of use.

[0043] Expressions such as "perimeter(s)", "peripherally" refer to features and / or parts of the container extending along or around the perimeter of the access opening, or to directions locally parallel to the perimeter of the access opening.

[0044] Expressions such as "outwardly", "externally" and the like refer to a direction locally perpendicular to the perimeter of the access opening, to features or parts of the container extending along that direction, away from the access opening, or moving along that direction, away from the access opening.

[0045] Expressions such as "inwardly", "internally" and the like refer to a direction locally perpendicular to the perimeter of the access opening, to features or parts of the container extending along that direction, towards the access opening, or displacements along that direction, towards the access opening.

[0046] A "substantially straight section" means a portion of the perimeter of the access opening that is either straight or has a curvature such that at any point in it the ratio of the radius of the perimeter obscuring circle to the maximum dimension of the container 1 is greater than 0.5.

[0047] A non-straight section means a portion of the perimeter of the access opening that is angled or has a curvature such that at any point in it the ratio of the radius of the obscuring circle of the perimeter to the maximum dimension of the container 1 is less than 0.5. The possible curvature of each non-straight section is at least an order of magnitude greater than the possible curvature of the substantially straight sections.

[0048] Unless specified otherwise, the following description and the appended claims relate to an undeformed configuration of the container that is the subject matter of the present invention.

[0049] An "undeformed configuration" means the configuration assumed by the container when no external force is applied to it (except for forces having a negligible impact on the deformation of the container, such as the force of gravity).

[0050] "Deformed configuration" refers to the configuration assumed by the container, or a part of it, when one or more external forces deform it, changing its shape with respect to the undeformed configuration.

[0051] The present invention, in at least one of the aforementioned aspects, may be implemented in one or more of the following ways, possibly combined.

[0052] Preferably, said at least one non-straight section is a curved section.

[0053] Preferably, said perimeter lies in an access plane to said containment volume defined by said access opening.

[0054] Preferably, said edge wall extends around said perimeter, preferably in a continuous manner.

[0055] Preferably, said hinge portions are configured to allow rotation of their respective support ribs about different axes of rotation.

[0056] Preferably, said hinge portions have a flexural rigidity at least one order of magnitude lower than said support ribs.

[0057] Preferably, said support ribs have at least a partially double-curved geometry, configured to make them at least an order of magnitude stiffer than said hinge portion.

[0058] Preferably, said axes of rotation are incident to each other.

[0059] Preferably, said axes of rotation are coplanar.

[0060] Preferably, said axes of rotation lie in a plane parallel to said access plane.

[0061] Preferably, said perimeter comprises a plurality of non-straight sections. Preferably, said perimeter comprises four non-straight sections.

[0062] Preferably, said perimeter comprises a plurality of non-straight sections. Preferably, said perimeter comprises four substantially straight lines. Preferably, the perimeter of the access opening has two first straight sections parallel to each other. Preferably, the perimeter of the access opening has two second substantially straight sections parallel to each other. Preferably, the second substantially straight sections are perpendicular to the first substantially straight sections.

[0063] Preferably, each non-straight section is interposed between two substantially straight sections. Preferably, each non-straight section is interposed between one of said first non-straight sections and one of said second non-straight sections.

[0064] Preferably, said edge wall comprises a plurality of edge wall portions. Preferably, said edge wall comprises four edge wall portions. Preferably, said edge wall comprises an edge wall portion for each substantially straight section of said perimeter.

[0065] Preferably, each edge wall portion is placed at a respective substantially straight section of said perimeter.

[0066] Preferably, said edge wall comprises a plurality of connecting portions. Preferably, said edge wall comprises four connecting portions. Preferably, said edge wall comprises a connecting portion for each non-straight section of said perimeter.

[0067] Preferably, each connecting portion is placed at a respective non- straight section of said perimeter.

[0068] Preferably, each connecting portion is peripherally interposed between two respective edge wall portions.

[0069] Preferably, each non-straight section is a curved section.

[0070] Preferably, each non-straight section has a curvature at least an order of magnitude greater than said substantially straight section.

[0071] Preferably, said containment body comprises a side wall extending around said containment volume between a support base of the container and the perimeter of said access opening.

[0072] Preferably, an opening bend is placed between the containment body and the edge wall.

[0073] Preferably, said opening bend defines an angle between the containment body and the edge wall of at least 40°, preferably at least 50°, more preferably at least 60°, even more preferably at least 70°, even more preferably at least 80°, for example about 85°.

[0074] Preferably, said opening bend extends around the perimeter of the access opening.

[0075] Preferably, said edge wall comprises an opening portion.

[0076] Preferably, said opening portion is adjacent to said access opening.

[0077] Preferably, said opening portion extends outwardly from said access opening.

[0078] Preferably, said opening portion is interposed between said hinge portion and said opening bend.

[0079] Preferably, said opening portion is contiguous to said opening bend.

[0080] Preferably, said opening portion is flat.

[0081] Preferably, said opening portion is parallel to said access plane.

[0082] Preferably, said opening portion lies in said access plane. Preferably, said edge wall comprises a side portion.

[0083] Preferably, said side portion is interposed between said access opening and said hinge portion.

[0084] Preferably, said side portion extends downwardly from said opening portion.

[0085] Preferably, said side portion extends downwardly and outwardly from said opening portion.

[0086] Preferably, said side portion forms an angle with said access plane comprised between 60° and 90°, more preferably between 65° and 89°, more preferably between 70° and 88°, even more preferably between 75° and 87°, even more preferably between 80° and 86°, e.g. approximately 85°.

[0087] Preferably, said side portion follows a conical surface at said at least one non-straight section of the perimeter of the access opening.

[0088] Preferably, said side portion has a flexural stiffness at least one order of magnitude greater than said hinge portion.

[0089] Preferably, said container is made of a single sheet of plastic material.

[0090] Preferably, said container is made of polyethylene terephthalate.

[0091] Preferably, said single sheet has a thickness comprised between 200 pm and 2000 pm.

[0092] Preferably said container is produced by moulding, preferably thermoforming.

[0093] Preferably, each hinge portion extends from said side portion outwardly.

[0094] Preferably, each hinge portion comprises a thinner portion of said sheet than the rest of said edge wall.

[0095] Preferably, each hinge portion comprises a thinner portion of said sheet than the respective support rib and / or side portion.

[0096] Preferably, each hinge portion comprises a bottom portion.

[0097] Preferably, said bottom portion is flat.

[0098] Preferably, said bottom portion is parallel to said access plane.

[0099] Preferably, said hinge portion is arranged below said access plane.

[0100] Preferably, each hinge portion defines a respective axis of rotation of said axes of rotation.

[0101] Preferably, each hinge portion defines its respective axis of rotation at the respective bottom portion.

[0102] Preferably, said outer edge lies in an edge plane.

[0103] Preferably, said edge plane is parallel to said access plane.

[0104] Preferably, said edge plane is placed below said access plane.

[0105] Preferably, said bottom portion is vertically interposed between said access plane and said edge plane.

[0106] Preferably, said hinge portion comprises at least one inclined portion extending from said bottom portion towards said edge plane and towards said connecting portion.

[0107] Preferably, said bottom portion extends parallel to the respective substantially straight section. Preferably, said inclined portion extends in a direction having a component parallel to the respective substantially straight section of the perimeter moving away from said bottom portion and a component directed downwardly.

[0108] Preferably, each hinge portion comprises two inclined portions.

[0109] Preferably, each hinge portion extends along a respective main longitudinal direction substantially parallel to said substantially straight section.

[0110] Preferably, the axis of rotation of each hinge portion extends along the respective main longitudinal direction.

[0111] Preferably, a projection of each axis of rotation on the edge plane intersects said outer edge at said recess.

[0112] Preferably, said two inclined portions are placed at opposite longitudinal ends of said bottom portion.

[0113] Preferably, said at least one bottom portion is placed at said substantially straight section of the perimeter of the access opening.

[0114] Preferably, said at least one inclined portion is placed at said nonstraight section of the perimeter of the access opening.

[0115] Preferably, said hinge portion is defined by a U-shaped bend in said edge wall.

[0116] Preferably, said U-shaped bend is defined by said side portion and the respective support rib.

[0117] Preferably, each support rib comprises a support portion. Preferably, said support portion is flat.

[0118] Preferably, said support portion is placed above said edge plane.

[0119] Preferably, said support portion is raised with respect to said hinge portion.

[0120] Preferably said support portion lies in a support plane.

[0121] Preferably, the support portions of said support ribs lie in said support plane.

[0122] Preferably, said support plane is parallel to said access plane.

[0123] Preferably, said support plane is placed below said access surface.

[0124] Preferably, said support plane is interposed between said access plane and said edge plane.

[0125] Preferably, said support rib comprises a first side portion extending from said hinge portion to said support portion.

[0126] Preferably said first side portion is substantially vertical.

[0127] Preferably, said support rib comprises a second side portion extending from said support portion towards said edge plane.

[0128] Preferably, said second side portion forms an angle with said support portion comprised between 60° and 90°, more preferably between 65° and 89°, more preferably between 70° and 88°, even more preferably between 75° and 87°, even more preferably between 80° and 86°, e.g. approximately 85°.

[0129] Preferably, said support rib comprises at least one end portion placed at a longitudinal end of said support rib. Preferably, said at least one end portion is arranged at said nonstraight section.

[0130] Preferably, at said at least one end portion, the first side portion of said support rib comprises a concave surface.

[0131] Preferably, at said at least one end portion, the second side portion converges towards the first side portion to define a tapered end portion of the support rib.

[0132] Preferably, said support rib comprises two end portions.

[0133] Preferably, said edge wall portion comprises an edge portion.

[0134] Preferably, said edge portion edge extends from said support rib to said outer edge.

[0135] Preferably, said edge portion extends from said second side portion to said outer edge.

[0136] Preferably, said edge portion lies in said edge plane.

[0137] Preferably, said edge portion has an extension in a direction locally perpendicular to the perimeter of the access opening less than 5 mm, preferably less than 3 mm, more preferably less than 2 mm, even more preferably less than 1.5 mm, e.g. about 1 mm.

[0138] Preferably, said connecting portion comprises a flat portion of said sheet.

[0139] Preferably, said connecting portion lies in said edge plane.

[0140] Preferably, said connecting portion extends from said side portion to said outer edge.

[0141] Preferably, the support ribs of said edge wall portions are interrupted at said connecting portion.

[0142] Preferably, each support rib comprises an end portion extending from the respective support portion to said connecting portion.

[0143] Preferably said end portion extends from said support plane to said edge plane.

[0144] Preferably, said connecting potion interrupts the support ribs of the edge wall portions between which it is peripherally interposed.

[0145] Preferably, a distance between the perimeter of the access opening and said outer edge is shorter at said connecting portion than at at least two edge wall portions.

[0146] Preferably, said connecting portion has a smaller extension than said at least two edge wall portions. The extent of the connecting and edge wall portions is measured from the perimeter of the access opening to said outer edge, perpendicular to the perimeter of the access opening and parallel to said access plane.

[0147] Preferably, said at least one connecting portion defines a recess in the edge wall at said non-straight section of the perimeter of the access opening.

[0148] Preferably, said recess is defined by a concave section of said outer edge.

[0149] Preferably, said recess has a concave shape in said edge plane.

[0150] Preferably, at said recess the direction of curvature of the outer edge is opposite to the direction of curvature of the non-straight section of the perimeter of the access opening.

[0151] Preferably, said recess of the connecting portion divides the support ribs of the portions of the edge wall between which it is inserted.

[0152] Preferably, at said connecting portion, said outer edge protrudes from said side portion with an extension of less than 5 mm, preferably less than 3 mm, more preferably less than 2 mm, even more preferably less than 1.5 mm, e.g. about 1 mm.

[0153] Preferably, said connecting portion is coplanar to said edge portion.

[0154] Preferably, said connecting portion is contiguous to said edge portion.

[0155] Preferably, said support ribs of said at least two edge wall portions are structurally independent of each other. Preferably, said support ribs of said at least two edge wall portions are not connected by any structure higher than said edge plane through said connecting portion.

[0156] Preferably, each support rib is interposed between said access plane and said outer edge plane along a direction substantially perpendicular to the access plane.

[0157] Preferably, said edge wall comprises an opening portion interposed along a direction substantially parallel to the access plane between said access opening and said hinge portion.

[0158] Preferably, each hinge portion is defined by a U-shaped bend of the edge wall interposed between said opening portion and the respective support rib.

[0159] Preferably, said opening portion defines a top of said disposable container. Preferably, said U-shaped bend is open to said at least one connecting portion.

[0160] Preferably, said support rib is not structurally connected to said opening portion by any structure higher than said hinge portion.

[0161] Preferably, said support rib is delimited by the respective hinge portion, the respective edge portion and two adjacent rejoining portions.

[0162] Preferably, said support rib is delimited only by the respective hinge portion, the respective edge portion and two adjacent rejoining portions.

[0163] Preferably, said edge wall is deformable between an undeformed configuration and a deformed configuration.

[0164] Preferably, said edge wall is deformable between the undeformed configuration and the deformed configuration by bending said hinge portion.

[0165] Preferably, in the deformed configuration, said support ribs are rotated about their respective axes of rotation with respect to the undeformed configuration.

[0166] Preferably, in the deformed configuration, the first side portion extends outwardly from the hinge portion.

[0167] Preferably, in the deformed configuration, the support portion extends downwardly from the first side portion.

[0168] Preferably, in the deformed configuration, the second side portion extends inwardly from the support portion.

[0169] Preferably, in the deformed configuration, the outer edge is arranged internally with respect to the support portion.

[0170] Preferably, rotating said support ribs of said at least two edge wall portions comprises deforming the respective hinge portions.

[0171] Preferably, rotating said support ribs of said at least two edge wall portions comprises moving said outer edge towards said containment body.

[0172] Preferably, rotating said support ribs of said at least two edge wall portions is carried out while applying said film to said edge wall.

[0173] Preferably, rotating said support ribs of said at least two edge wall portions is done by pressing said support ribs downwardly.

[0174] Preferably, in the deformed configuration, each hinge portion is folded along a respective bending line that follows the respective axis of rotation.

[0175] Preferably, said bending line flows into the connecting portion.

[0176] Preferably, said bending line flows into the outer edge at the connecting portion.

[0177] Preferably, said bending line flows into the outer edge at the recess in the connecting portion.

[0178] The features and advantages of the present invention will result from the following detailed description of some example embodiments thereof, provided solely by way of non-limiting example, in which reference will be made to the accompanying drawings, wherein:

[0179] - Figure 1 shows a perspective view of a disposable container according to the present invention; - Figure 2 shows a top view of the disposable container in Figure

[0180] - Figure 3 shows a side view of the disposable container in Figure i;

[0181] - Figure 4 shows a perspective view of a detail of the disposable container in Figure 1;

[0182] - Figure 5 shows a different view of a detail of the disposable container in Figure 1.

[0183] A disposable plastic container according to the present invention is illustrated in the appended figures, where it is indicated by the numerical reference 1.

[0184] The container 1 consists of a single sheet 5 made of plastic material. The plastic material of the sheet 5 may consist of, or comprise, one or more polymer materials such as polystyrene, oriented polystyrene, polypropylene, polyethylene terephthalate, polyvinyl chloride, polylactic acid, or a bio-plastic such as Mater-Bi. Preferably the sheet 5 is made of polyethylene terephthalate, at least partly from recycled material. The sheet 5 has a thickness comprised between 200 pm and 2000 pm.

[0185] The container 1 comprises a containment body 8. The containment body 8 has a concave shape. The containment body 8 defines a containment volume 10 configured to house a product, e.g. a food product. A plurality of corrugations 11 are defined on the containment body 8 to stiffen the container 1.

[0186] The containment body 8 comprises a flat or substantially flat bottom wall 12. The bottom wall 12 is defined by a central region of the sheet 5. The bottom wall 12 is horizontal or substantially horizontal. The bottom wall 12 delimits the bottom of the containment volume 10 and is configured to support any products inside the containment volume 10. In the embodiment illustrated in Figures 1 and 2, the bottom wall 12 has a substantially quadrangular shape, in particular substantially rectangular.

[0187] The bottom wall 12 defines a support base 13 configured to stably support the container 1 on a flat horizontal surface. The support base 13 is defined by one or more bottom wall surfaces 12 aligned along a support plane Pl and configured to contact a horizontal flat surface when the container 1 is resting on it in the preferred use configuration. In the embodiment illustrated, the support base 13 is defined by a rib extending along the perimeter of the back wall 12.

[0188] The containment body 8 comprises a side wall 15 bordering the bottom wall 12. The side wall 15 extends around the containment volume 10, delimiting it laterally. The side wall 15 protrudes upwardly from the bottom wall 12, away from the support surface Pl. The side wall 15 is defined by a region of the sheet 5 extending around, and bordering onto, the central region of the sheet 5 that defines the bottom wall 12.

[0189] The side wall 15 is joined to the bottom wall 12 by a connector 16, preferably rounded. In an embodiment not illustrated, the connector 16 is essentially a corner. The extension of the side wall 15 away from the bottom wall 12 defines the height of the containment volume 10. The containment body 8 can be tapered. The side wall 15 can form an obtuse angle with the support surface Pl to facilitate the production and stacking of the containers 1. In the embodiment illustrated, the corrugations 11 extend from the bottom wall 12 to the side wall 15 through the connector 16.

[0190] The side wall 15 may comprise a plurality of stop portions 17 projecting outwardly in relief, as illustrated in Figure 3.

[0191] The containment body 8 defines an access opening 18, which is open to the containment volume 10. The access opening 18 provides access to the containment volume 10 from above, to store a product in the containment volume 10 or to remove the product from the containment volume 10. The access opening 18 defines an access plane P2 to the containment volume 10. The access opening 18 lies in the access plane P2. The access plane P2 is defined on the containment volume 10, and delimits it from above. The access plane P2 is also parallel to and spaced apart from the support plane Pl. The containment body 8 extends from the support plane Pl to the access plane P2.

[0192] The access opening 18 is delimited by a perimeter 19. The perimeter 19 lies in the access plane P2. The perimeter 19 of the access opening 18 delimits the containment body 8 from above.

[0193] The perimeter 19 of the access opening 18 comprises a plurality of substantially straight sections 19a and a plurality of non-straight sections 19c. Each non-straight section 19c is interposed between two substantially straight sections 19a.

[0194] The substantially straight sections 19a are either straight or have a slight curvature. At any point on the substantially straight sections 19a the ratio of the radius of the osculating circle of perimeter 19 to the maximum dimension of the container 1 (e.g. length or width) is greater than 0.5. For example, if the container is 200 mm long and 100 mm wide, it may have a minimum osculating circle radius of 400 mm on the cutting edge.

[0195] In the embodiment illustrated, the perimeter 19 of the access opening 18 is essentially rectangular, with rounded vertices. In particular, the perimeter 19 has two first substantially straight sections 19a, parallel to each other, two second substantially straight sections 19a parallel to each other and perpendicular to the first substantially straight sections 19a, and four non-straight sections 19c, each placed between a respective first substantially straight section 19a and a respective second substantially straight section 19a to connect them. In the embodiment illustrated, the non-straight sections 19c are curved. In non-illustrated embodiments, the non-straight sections 19c may be at an angle. In further embodiments, the perimeter 19 can have different geometries. For example, in an embodiment, the perimeter 19 may be polygonal, and comprise a different number of substantially straight sections 19a and non-straight sections 19c.

[0196] The container 1 comprises an edge wall 20 extending peripherally around the access opening 18. The edge wall 20 is defined by a region of the sheet 5 bordering onto, and extending around, the region of the sheet 5 defining the containment wall 8.

[0197] The edge wall 20 is connected to the containment body 8 by an opening bend 22 placed at the access opening 18 and lying in the access plane P2.

[0198] The opening bend 22 defines, in a plane perpendicular to the perimeter 19 of the access opening 18, an angle between the containment body 8 and the edge wall 20 of at least 40°, preferably at least 50°, more preferably at least 60°, even more preferably at least 70°, even more preferably at least 80°, in particular about 85°.

[0199] The edge wall 20 extends outwardly from the opening bend 22 to an outer perimeter edge 23 of the container 1. The outer edge 23 comprises a cutting corner of the sheet 5 and defines an outer perimeter end of the container 1. The outer edge 23 lies in an edge plane P3. The edge plane P3 is parallel to the access plane P2. The edge plane P3 is arranged below the access plane P2. The edge plane is preferably interposed between the support plane Pl and the access plane P2.

[0200] The edge wall 20 extends continuously around, and along, the perimeter 19 of the access opening 18.

[0201] The edge wall 20 comprises an opening portion 26 extending outwardly from the bend 22 away from the access opening 18. The opening portion 26 extends preferably continuously around the opening 18. The opening portion 26 lies in the access plane P2. In the embodiment illustrated, the opening portion 26 has a dimension, measured parallel to the access plane P2 in a section plane perpendicular to the perimeter 19 of the access opening, of less than 3 mm, preferably about 2 mm. This dimension is uniform around the perimeter 19 of the opening 18. The opening portion 26 is defined by a region of the sheet 5 bordering onto, and extending around, the region of the sheet 5 defining the containment body 8.

[0202] The edge wall 20 comprises a lateral portion 32. The side portion 32 extends downwardly and preferably outwardly from the opening portion 26. The opening portion 26 extends preferably continuously around the opening 18. The side portion 32 forms an angle with the access plane P2 of at least 40°, preferably at least 50°, more preferably at least 60°, even more preferably at least 70°, even more preferably at least 80°, in particular about 85°.

[0203] The side portion 32 is substantially parallel to the perimeter 19 of the access opening 18. At the substantially straight sections 19a of the perimeter 19, the side portion 32 is substantially straight and substantially parallel to the perimeter 19 of the access opening 18. At the non-straight sections 19c of the perimeter 19, the side portion 32 is curved and preferably follows a conical or substantially conical surface. The hinge portion 26 is defined by a region of the sheet 5 bordering onto, and extending around, the region of the sheet 5 defining the opening portion 26.

[0204] The edge wall 20 comprises a plurality of edge wall portions 33. Each edge wall portion 33 is placed at a respective substantially straight section 19a of the perimeter 19 of the access opening 18. Each edge wall portion 33 extends along the respective substantially straight section 19a of the perimeter 19 of the access opening 18. The edge wall 20 has a number of edge wall portions 33 equal to the number of substantially straight sections 19a of the perimeter 19. In the embodiment illustrated, the edge wall 20 comprises four edge wall portions 33.

[0205] At the edge wall portions 33, the distance between the outer edge 23 and the opening bend 22 measured on the access plane P2 and perpendicular to the perimeter 19 of the access opening 18, is substantially constant along the respective substantially straight sections 19a of the perimeter 19 of the access opening 18.

[0206] Each edge wall portion 33 comprises a respective hinge portion 34 configured to allow, and preferably promote, preferably elastic bending of the edge wall 20, such that the bending is localised at the hinge portion 34 itself. Each hinge portion 34 thus defines a respective axis of rotation R parallel or substantially parallel to the respective substantially straight section 19a of the perimeter 19. As with the substantially straight sections 19a of the perimeter 19, each axis of rotation R is substantially straight and can have a maximum curvature such that the ratio of the radius of the osculating circle to the maximum dimension of the container 1 (e.g. length or width) is greater than 0.5.

[0207] The hinge portion 34 is contiguous to the side portion 32. Each hinge portion 34 extends in a substantially straight manner substantially parallel to the respective substantially straight portion 19a of the perimeter 19. Each hinge portion 34 is defined by a region of the sheet 5 bordering onto, and extending around, the region of the sheet 5 defining the side portion 32.

[0208] At the hinge portions 34, the sheet 5 exhibits a localised thinning intended to promote its bending along the axis of rotation R. The localised thinning is formed during the moulding of the container 1 by elongating the sheet 5 by the shape of the edge wall 20.

[0209] Each hinge portion 34 comprises a bottom portion 36. The bottom portion 36 is preferably flat and parallel to the edge plane P3. The bottom portion 36 is located at a central part of the respective substantially straight section 19a. In the preferred embodiment shown, the bottom portion 36 is raised with respect to the edge plane P3. The bottom portion 36 is vertically arranged between the edge plane P3 and the access plane P2.

[0210] In the preferred embodiment illustrated, each hinge portion 34 further comprises two inclined portions 37. The inclined portions 37 extend from the bottom portion 36 towards the edge plane P3 in an inclined direction with respect to the edge plane P3 having a component locally parallel to the perimeter 19 and a component facing downwardly. The inclined portions 37 are placed at the respective opposite ends of the substantially straight section 19a. Each inclined portion 37 is placed at an intersection between the aforementioned substantially straight section 19a and the nonstraight section 19c adjacent thereto.

[0211] Each edge wall portion 33 comprises a support rib 40. Each support rib 40 is contiguous to the respective hinge portion 34. Each support rib 40 defines a raised structure with respect to the respective hinge portion 34. Each support rib 40 also defines a structure raised with respect to the edge plane P3. Each support rib 40 extends in a substantially straight manner substantially parallel to the respective substantially straight portion 19a of the perimeter 19. Each support rib 40 is defined by a region of the sheet 5 bordering onto the region of the sheet 5 defining the hinge portion 34.

[0212] Each hinge portion 34 is interposed between the respective support rib 40 and the access opening 18. The hinge portion 34 is configured to allow the support rib 40 to rotate about its respective axis of rotation R when the support rib 40 is pressed downwardly. The hinge portion 34 is configured to allow the support rib 40 to rotate about the axis of rotation R by deforming. The edge wall portion 33 is configured such that a pressure on the support rib 40 capable of deforming the hinge portion does not deform, or deforms negligibly, the rest of the edge wall portion 33 and in particular the support rib 40.

[0213] Each axis of rotation R lies on the bottom 36 of the hinge portion 34. Each axis of rotation R is substantially parallel to its respective substantially straight line 19a. The axes of rotation R are distinct from each other. The axes of rotation R. are preferably coplanar to each other.

[0214] Each support rib 40 comprises a first side portion 42. The first side portion 42 extends upwardly from the respective hinge portion 34. In the illustrated embodiment, the first side portion 42 extends vertically upwardly from the hinge portion 34. The first side portion

[0215] 42 is contiguous to the hinge portion 34.

[0216] The first side portion 42 is substantially planar along the substantially straight section 19a of the perimeter 19. The first side portion 42 partially extends along the non-straight section 19a of the perimeter 19. The first side portion 42 forms a concave surface

[0217] 43 at the non-straight section 19a of the perimeter 19.

[0218] As visible in Figure 5, the side portion 32, the hinge portion 34 and the first side portion 42 define a U-shaped bend in a section plane locally perpendicular to the perimeter 19. This "U" shape contributes to the elongation of the sheet 5 and the consequent thinning of the hinge portion 34 during the moulding of the container 1.

[0219] In possible alternative embodiments not illustrated, according to the present invention, the hinge portion 34 may take on different conformations, for example it may comprise a weakening portion configured to facilitate elastic bending of the edge wall 20 located at the hinge portion 34 itself.

[0220] Each support rib 40 comprises a support portion 44. The support portion 44 extends outwardly from the first side portion 42. In the illustrated embodiment, the support portion 44 is flat. In the illustrated embodiment, the support potion 40 is placed above the hinge portion 34. In the illustrated embodiment, the support potion 40 is placed between the edge plane P3 and the access plane P2. The support portion 44 is contiguous to the first side portion 42.

[0221] The support ribs 40 of the edge wall 20 are configured so that, by wrapping a protective film around the container 1 so as to occlude the access opening 18, the protective film contacts the support portions 44 and presses down on the support ribs 40, preferably causing them to rotate about the respective axes of rotation R.

[0222] The support portions 44 lie in a common support plane P4. The support plane P4 is parallel to, and interposed between, the access plane P2 and the edge plane P4.

[0223] Each support rib 40 comprises a second side portion 46. The second side portion 46 extends downwardly and preferably outwardly from the support portion 44. The second side portion 46 extends from the support portion 44 to the edge plane P3. The second side portion 46 is contiguous to the support portion 44.

[0224] The second side portion 46 forms an angle with the edge plane P3 of at least 40°, preferably at least 50°, more preferably at least 60°, even more preferably at least 70°, even more preferably at least 80°, in particular about 85°.

[0225] The second side portion 46 is substantially planar along the substantially straight section 19a of the perimeter 19. The second side portion 46 extends partially along the non-straight section 19a of the perimeter 19.

[0226] Each support rib 40 extends along a main longitudinal direction substantially parallel to the respective substantially straight section 19a of the perimeter 19. The support rib 40 comprises opposite end portions 47 arranged at opposite longitudinal ends of the support rib 40. Each end potion 47 extends from the support portion 44 downwardly to the edge plane P3. At each end portion 47, the first side portion 42 and the second side portion 46 converge towards each other so as to define a tapered longitudinal end of the support rib 40. At each end portion 47, the first side portion 42 comprises the concave surface 43.

[0227] Each edge wall portion 33 also comprises an edge portion 48. The edge portion 48 extends from the support rib 40 to the outer edge 23. The edge portion 48 lies, preferably entirely, in the edge plane P3. The edge portion 48 is contiguous to the support rib 40, in particular to the second side portion 46. The edge portion 48 has a dimension, measured parallel to the edge plane P3 in a section plane perpendicular to the perimeter 19 of the access opening 18, of less than 3 mm, preferably less than 2 mm, preferably about 1 mm. This dimension is uniform along the substantially straight sections 19a of the perimeter 19.

[0228] The edge wall 20 comprises a plurality of connecting portions 50. Each connecting portion 50 is placed at a respective non-straight section 19c of the perimeter 19 of the access opening 18. Each connecting portion 50 extends along the respective non-straight section 19c of the perimeter 19 of the access opening 18. Each connecting portion 50 is peripherally interposed between, and contiguous to, two respective edge wall portions 33. Each connecting portion 50 extends outwardly from the side portion 32 to the outer edge 23.

[0229] The edge wall 20 has a number of connecting portions 50 equal to the number of non-straight sections 19c of the perimeter 19. In the illustrated embodiment, the edge wall 20 comprises four connecting portions 50.

[0230] Each connecting portion 50 is configured to allow the support ribs 40 of the adjacent edge wall portions 33 to rotate about their respective axes of rotation R independently of each other. The rotation of the support ribs 40 about the respective axes of rotation R occurs without significant deformation of the support ribs 40 themselves and results in a lowering of the outer edge 23 and a nearing of the outer edge 23 to the containment body 8.

[0231] The connecting portion 50 lies, preferably entirely, in the edge plane P3. The connecting portion 50 extends between the hinge portions 34 of the edge wall portions 33 contiguous thereto. The connecting portion 50 also extends between the support ribs 40 of the two edge wall portions 33 contiguous thereto. The connecting portion 50 is contiguous and coplanar to the edge wall 48.

[0232] Each connecting portion 50 defines a recess 51 of the outer edge 23, at which the outer edge 23 has a concave profile. At the recess 51, the distance between the outer edge 23 and the non-straight section 19c of the perimeter 19 is less than the distance between the outer edge 23 and the substantially straight section 19a of the perimeter 19 at the edge wall portions 33 (the above distances are measured locally perpendicular to the perimeter 19). The recess 51 is defined by a gap of material. At the recess 51, the outer edge has an opposite curvature with respect to the respective nonstraight section 19c of the perimeter 19.

[0233] The axes of rotation R of the hinge portions 34 of two edge wall portions 33 adjacent to a connecting portion 50 intersect each other at the recess 51. In particular, they intersect each other at a point external to the outer edge 23, as illustrated in Figure 2. The connecting portion 50 has an extension, away from the side portion 32, of less than 5 mm, preferably less than 3 mm, even more preferably less than 5 mm, for example about 1 mm.

[0234] Each hinge portion 34 is defined by a U-shaped bend extending along the respective main longitudinal direction substantially parallel to the respective substantially straight section 19a of the perimeter 19 to the connecting portion 50, at which the bend is open to the connecting portion.

[0235] The connecting portion 50 is coplanar and in substantial continuity with the edge portion 48.

[0236] The support rib 40 is defined by a raised structure delimited by the hinge portion 34, the edge portion 48 and the connecting portion 50.

[0237] Each edge wall portion 33 is deformable from an undeformed configuration (described above) and a deformed configuration in which the support ribs 40 are rotated about the respective axis of rotation R.

[0238] In the deformed configuration, the edge wall portion 33 may abut against one or more of the stop portions 17 that define a limit stop to the rotation of the support ribs 40 about the respective axis of rotation R.

[0239] In the deformed configuration, the hinge portion 34 is bent along a respective bending line not illustrated, which essentially follows the axis of rotation R. The bending line flows into the connecting portion 50. When the two edge wall portions 33 adjacent to a connecting portion 50 are in the deformed configuration, the bending lines of the respective hinge portions 34 converge with each other at the connecting portion 50.

[0240] In the deformed configuration, the first side portion 42 extends outwardly from the hinge portion 34. In the deformed configuration, the first side portion 42 extends from the hinge portion 34 in a divergent direction with respect to the side portion 32. In the deformed configuration, the support portion 44 extends downwardly from the first side portion 42. In the deformed configuration, the second side portion 46 extends inwardly from the support portion.

[0241] In the deformed configuration, the outer edge 23 is located further inwardly with respect to the support surface.

[0242] To package a product (not illustrated), e.g. a perishable food product, a disposable container 1 of the type described above is provided.

[0243] A product of the containment volume 10 is then placed through the access opening 18. The product rests on the bottom wall 12 of the containment body 8.

[0244] Next, a film is applied to the edge wall 20 to cover the access opening 18. The film makes contact with the opening portion 26 and the support portions 44 of the support ribs 40.

[0245] During application of the film, using film 45 or special pressers (not shown), the support ribs 40 are pressed to deform the edge wall portions 33 between the undeformed and deformed configurations.

[0246] The edge wall portions 33 are deformed at the hinge portions 34 by rotating the support ribs 40 about the respective axes of rotation R. The deformation of the edge wall 34 causes the outer edge 23 to move closer to the containment body 8 at the edge wall portions. In the deformed configuration, the outer edge 23 is positioned below the support ribs 40. In particular, the outer edge 23 is positioned towards the containment volume 10.

[0247] The connecting portions 50 allow the support ribs 40 to rotate with respect to each other without deforming each other and without causing localised lifting of the outer edge 50.

[0248] At the connecting portions 50, the film is stretched between the end portions 47 of the adjacent support ribs 40 in a deformed configuration and kept spaced apart from the outer edge 23 at the recess 51.

[0249] In this way, the outer edge 23 does not come into contact with the film. Next, the film is wrapped around the containment body 8, keeping the edge wall portions 33 in a deformed configuration. The packaging can be completed by further wrapping of film around the container 1, as required.

Claims

CLAIMS1. Disposable container (1) made of plastic material, comprising: a containment body (8) in which a containment volume (10) is defined; an access opening (18) to said containment volume (10), delimited by a perimeter (19) comprising at least two substantially straight sections (19a); an edge wall (20) extending from said perimeter (19) to an outer edge (23) of said disposable container (1), said edge wall (20) comprising at least two edge wall portions (33) and at least one connecting portion (50) peripherally interposed between said at least two edge wall portions (33) at at least one non-straight section (19c) of the perimeter (19) of the access opening (18); wherein each edge wall portion (33) comprises: a support rib (40) distal from said access opening (18) and on which a film may be applied to close said access opening (18); and a hinge portion (34) interposed between said support rib (40) and said access opening (18), said hinge portion (34) being configured to allow a rotation of said support rib (40) relative to said containment body (8); and wherein said at least one connecting portion (50) of the edge wall (20) is configured to allow the support ribs (40) of said at least two edge wall portions (33) to rotate independently of each other about respective rotation axes (R.) substantially parallel to said at least two substantially straight sections (19a) of the perimeter (19) of the access opening (18).

2. Disposable container (1) according to claim 1, wherein a distance between the perimeter (19) of the access opening (18) and said outer edge (23) is lower, at said connecting portion (50),than at at least two edge wall portions (33).

3. Disposable container (1) according to claim 2, wherein said at least one connecting portion (50) defines a recess (51) of the edge wall (20) at said non-straight section (19c) of the perimeter (19) of the access opening (18).

4. Disposable container (1) according to claim 3, wherein said support ribs (40) of said at least two edge wall portions (33) are structurally independent of each other.

5. Disposable container (1) according to any one of the preceding claims, wherein said access opening (18) lies in an access plane (P2) and said outer edge (23) lies in an edge plane (P3), parallel to, and lower than, said access plane (P2).

6. Disposable container (1) according to claim 5, wherein each support rib (40) is interposed between said access plane (P2) and said edge plane (P3) along a direction substantially perpendicular to the access plane (P2).

7. Disposable container (1) according to any one of the preceding claims, wherein said edge wall (20) comprises an opening portion (26) extending between said access opening (18) and said hinge portion (34), and wherein each hinge portion (34) is defined by a U-shaped bend of the edge wall (20) extending between said opening portion (26) and the respective support rib (40).

8. Disposable container (1) according to claim 7, wherein said U- shaped bend is open towards said at least one connecting portion(50).

9. Disposable container (1) according to any one of the preceding claims, wherein: said access opening (18) lies in an access plane (P2); said outer edge (23) lies in an edge plane (P3), parallel to, and lower than, said access plane (P2), said hinge portion (34) comprises a bottom portion (36) interposed between said access plane (P2) and said edge plane (P3) along a direction substantially perpendicular to the access plane (P2).

10. Disposable container (1) according to any one of the preceding claims, consisting of a single sheet (5) made of plastic material, preferably made of polyethylene terephthalate, with a thickness between 200 pm and 2000 pm.

11. Disposable container (1) according to any one of the preceding claims, produced by moulding, preferably thermoforming.

12. Packaging method comprising: providing a disposable container (1) comprising a containment body wherein a containment volume (10) is defined; placing a product in said containment volume (10) of the container through an access opening (18) to said containment volume (10), said access opening (18) being delimited by a perimeter (19) comprising at least two substantially straight sections (19a); applying a film on an edge wall (20) of the disposable container (1) extending from said perimeter (19) of the accessopening (18) to an outer edge (23) of said disposable container (1) to cover said access opening (18), said edge wall (20) comprising at least two edge wall portions (33) and at least one connecting portion (50) peripherally interposed between said at least two edge wall portions (33) at at least one non-straight section (19c) of the perimeter (19) of the access opening (18), each edge wall portion (33) comprising a support rib (40) distal from said access opening (18) and a hinge portion (34) interposed between said support rib (40) and said access opening (18); rotating said support ribs (40) of said at least two edge wall portions (33) relative to said containment body independently of each other around respective rotation axes (R.) substantially parallel to said at least two substantially straight sections (19a) of the perimeter (19) of the access opening (18).

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