WO1997008067A1

WO1997008067A1 - A stackable package

Info

Publication number: WO1997008067A1
Application number: PCT/DK1996/000355
Authority: WO
Inventors: Karin LØNBÆK
Original assignee: Danisco A/S
Priority date: 1995-08-25
Filing date: 1996-08-23
Publication date: 1997-03-06
Also published as: AU6698896A

Abstract

A stackable plastic package comprising a support part (1) to support the product to be packed and a cover part (8) to cover the product. The cover part and the support part are interconnected along a circumferential sealing seam in overlapping edge portions therebetween to define a compartment (11) for the product. At least one of the parts is substantially form-stable to provide the package with the desired shape. The sealing seam in the overlapping edge portions and the portions of the support part (1) and the cover part (8) respectively defining the compartment are substantially on right cylindrical surfaces with parallel generators and with the hollowness facing the same side. The support part (1) extends relative to the cover part (8) of an adjacent, corresponding package in a stack that abuts at least said part in opposite end portions (12, 13) adjacent to its outer ends when seen perpendicular to the generator.

Description

A stackable package

Technical Field

The invention relates to a stackable plastic package comprising a support part to support the product to be packed and a cover part to cover the product, the cover part and the support part being interconnected along a circumferential sealing seam in overlapping edge portions therebetween to define a compartment for the product and at least one of the parts being substantially form-stable to provide the package with the desired shape.

Background Art

This type of packages are widely used, for instance for packaging cold cuts. Packages are thus known, in which the support part is a plane, rigid sheet of material and the cover part is a soft plastic sheet which tightly covers the cold cuts being placed on the support part and further attached to the support part along a circumferential edge.

Moreover, packages are known comprising a rigid, tray-shaped support part having a plane bottom and a circumferential flange to which a plastic sheet is sealed to cover the packed product. Such packages having plane lower and upper surfaces offer no sideways guidance at stacking or sideways support between the individual packages in a stack.

Finally, FR-A1-2710031 discloses a package of the above type, in which the support part and the cover part are provided with cylindrical portions adapted to abut each other when stacked. The overlapping edge portions of the support part and the cover part are plane.

Brief Description of the Invention

The object of the invention is to provide a package of the above type which has improved stackability and presents the packed product and/or the information on the cover part in a better manner than known packages.

The package according to the invention is characterised in that the sealing seam in the overlapping edge portions and in the portions of the support part and the cover part respectively defining the compartment are arranged substantially on right cylindrical surfaces with parallel generators and with the hollowness facing the same side, and that the support part extends such relative to the cover part of an adjacent, correspon¬ ding package in a stack that it abuts at least said cover part in opposite portions adjacent to its outer ends when seen perpendicular to the generator.

As a result, when stacking the package is guided into the correct position and remains therein without sliding. By arranging the packed product and/or the information on the cover part on a cylindrical surface, the product and/or the information is presented in an improved manner than hitherto known, as it is more visible from the side. Finally, due to the cylindrical surfaces, the package has increased rigidity relative to packages with plane surfaces.

According to the invention, the cylindrical surface of one of the parts may be substan¬ tially coincident with the cylindrical surface of the sealing seam. As a result, a very simple embodiment of the invention is obtained, in which said part is formed of a preferably soft or semi-rigid film sheet and the second part is substantially form-stable and formed of a rigid or semi-rigid film sheet providing the package the desired shape and stackability.

Moreover, according to the invention, at least the cylindrical portion of the support part may be formed of a number of plane surfaces, in particular of two plane surfaces forming an obtuse angle with each other, preferably an angle being > 120°. A stack of cold cuts may thus be arranged on each of the plane surfaces, said stack of cold cuts being more readily visible when viewing the package from the side due to the inclination of the surfaces. Furthermore, according to the invention, at least the cylindrical portion of the support part may be a circular cylindrical surface.

According to the invention, the cylindrical portions may further be symmetrical about a centre plane perpendicular to the directrices of the cylindrical surfaces.

Moreover, according to the invention, the two cylindrical surfaces may be substanti¬ ally parallel. Consequently, the surfaces of cylindrical portions of the support part and the cover part are in surface contact with each other when stacking the packages, whereby high local stresses which may cause a deformation of the package are avoided.

Moreover, according to the invention, the support part may be tray-shaped with a convex bottom wall for supporting the product and side wall extending upwardly from the bottom wall and continuing into a circumferential, outwardly extending flange connected to the cover part. In this embodiment of the invention, the cover part may advantageously be formed of a plastic sheet sealed to the flange being on a right cylindrical surface.

According to the invention, the cover part may further be tray-shaped with a convex cover wall for covering the product and side walls extending downwardly from the cover wall and continuing at their lower ends into a circumferential, outwardly extending flange connected to the support part, said support part formed of a support sheet sealed to the flange of the cover part.

Furthermore, according to the invention, the cylindrical surface of the support part may have a rise which measured peφendicular to a plane through its outer abutment portions is higher or equal to 50% , preferably 100% of the height of the compartment at the said abutment portions. Even at a comparative low rise, the intended properties are obtained as to stackability and presentation of the contents of the package and/or the information stated on the cover part, the presentation, however, being improved at increasing rise. In practice, good results have been achieved with a rise correspond- ing to the height of the compartment.

Moreover, the cover part may be made of a transparent material in order to present the contents of the package.

Finally, according to the invention, the circumferential sealing seam between the support part and the cover part may be peelable to obtain an advantageous opening of the package.

Brief Description of the Drawings.

The invention is explained in detail below with reference to the drawings, in which

Fig. 1 is a perspective view of a first embodiment of a package according to the invention in a partially open state,

Fig. 2 is a side view of a stack of two packages in Fig. 1 in closed state,

Fig. 3 is a longitudinal section through a second embodiment of the package according to the invention,

Fig. 4 is a longitudinal section through a third embodiment of the package accord- ing to the invention and

Fig. 5 is a longitudinal section through a fourth embodiment of the package according to the invention.

Best Mode for Carrying Out the Invention

The embodiment of the package according to the invention shown in Figs. 1 and 2 comprises a substantially rectangular, tray-shaped support part 1 provided with a bottom wall 2 formed as a section of a right, circular cylindrical surface. The bottom wall 2 is adapted to support the product to be packed. A pair of opposite, longitudinal side walls 3,4 and a pair of opposite, transverse side walls 5, 6 extend upwardly from the bottom wall 2. When placed on a plane base, the outer, opposite end portions 12,13 of the bottom wall 2 abut said base. The side walls continue into an outwardly extending flange 7 at their upper ends. The flange 7 is on a right, circular cylindrical surface with a generator being parallel to the generator of the bottom wall 2. As best illustrated in Fig. 2, the radius of curvature r of the bottom wall 2 is smaller than the radius of curvature R of the cylindrical surface of the flange 7. The support part is symmetrical about a centre plane CP perpendicular to the directrices of the cylindrical surfaces. The rise h of the bottom wall 2 of the support part 1 when measured perpendicular to a plane SP through the opposite end portions 12, 13 corresponds substantially to the height H of the compartment 11 at the said the opposite end portions.

The package further comprises a cover part 8 in form of a transparent plastic sheet peelably sealed to the flange 7 of the support part along a circumferential sealing seam

9 to define a compartment 11 for the product to be packed. In Fig. 1 the cover part

8 is shown partially removed from the flange 7 of the support part and for illustrative reasons the sealing seam 9 is shown dotted on the peeled portion of the cover part as well as on a corresponding portion of the flange 7 of the support part 1. At an outer end portion, the cover part 8 is provided with a gripping member 10 extending beyond the adjacent portion of the flange 7 and being gripped to open the package.

As the radius of curvature of the cylindrical surface of the bottom wall 2 as mentioned is smaller than the cylindrical surface housing the flange 7, the opposite end portions

12,13 of the bottom wall 2 abut the cover part 8 of a subjacent package 1 in stack of packages, as illustrated in Fig. 2. When stacking the packages, the abutment portions

12,13 guide the package into the correct position relative to the subjacent package and thus ensure a stable stacking.

The embodiment of the package according to the invention shown in Fig. 3 comprises a rectangular, tray-shaped bottom part 21 provided with a bottom wall 22 formed as a cylindrical surface comprising two plane faces 34,35 forming a obtuse angle v of 150° with each other. A pair of transverse side walls 25,26 and a pair of longitudinal side walls, of which only one 24 is visible, extend upwardly from the bottom wall 22. The side walls continue into a circumferential flange 27 at their upper ends. The circumferential flange 27 is situated on a cylindrical surface parallel to the cylindrical surface of the bottom wall 22. The support part is symmetrical about a centre plane CP through the intersection between the two plane faces 34, 35 of the bottom wall 22.

A cover part 8 in form of a plastic sheet is sealed to the flange 27 of the support parts along a circumferential sealing seam 29. In the compartment 31 defined by the support part 21 and the cover part 8 a stack of cold cuts 36,37 is arranged on each of the plane wall portions 34,35 of the bottom wall 22. When stacking the package shown in Fig. 3, the complete bottom wall 22 of an upper package abuts the cover part 8 of the subjacent package. The shape of the bottom wall 22 and of the cover part 8 ensures a secure and stable stacking.

The embodiment of the invention shown in Fig. 4 comprises a support part 41 of a rigid material and shaped as a section of a right, circular cylindrical surface. A stack of cold cuts 56 is arranged on the support part 41. A cover part 48 in form of a flexible, soft plastic sheet is arranged tightly and retainingly on top of the stack of cold cuts 56 and attached to the support part 41 along a circumferential edge portion 49. The portion 42 of the cover part 48 abutting the stack 56 of cold cuts has the same cylindrical shape as the support part 41. As a result, said portion 42 of the cover part 48 abuts the support part 41 when the package is stacked, thus ensuring a stable stacking.

The embodiment of the package according to the invention shown in Fig. 5 comprises a tray-shaped cover part 68 provided with a concave wall 62 with a form of a right, circular cylinder. A pair of opposite, transverse side walls 65,66 and a pair of opposite, longitudinal side walls, of which only the wall 64 is visible, extend down¬ wardly. The side walls continue into an outwardly extending flange 67 at their lower ends. The flange 67 is on a right, circular cylindrical surface parallel to the cylindrical surface of the cover wall 62. The flange 67 of the cover part 68 is sealed along a circumferential sealing seam 69 to a support part 61 in form of a plastic sheet consequently having the same shape as the cylindrical surface on which the flange 67 is arranged. This support part 61 serves as a support of the product to be packed in the package. Since the flange 67 and the support part 61 has the same cylindrical shape as the cover wall 62, a secure and stable stacking of the package is obtained.

In the embodiment of the package according to the invention shown in Figs. 1 to 4, the support part can be made from any semi-rigid or rigid material, such as a PET/PE laminate or a PVC/PE laminate fhermo-formed into the desired shape and for instance with a thickness of 100 to 800 μm. In the embodiment according to the invention shown in Figs. 1 to 4, a semi-rigid or soft laminate, such as a PP/PE laminate, a PA/PE laminate, a PET/PE laminate or a PVC/PE laminate, can be used for the cover part, said laminate having a thickness of for instance 30 to 300. In the embodiment shown in Fig. 5, the cover part 62 preferably is made of one of the above semi-rigid or rigid materials, while the support part preferably is made of one of the above semi-rigid or soft laminates. Moreover, the laminates may comprise a barrier layer, for instance a metallization.

Claims

1. A stackable plastic package comprising a support pan (1, 21, 41, 61) to support the product to be packed and a cover part (8, 28, 48, 68) to cover the product, the cover part and the support part being interconnected along a circum- ferential sealing seam in overlapping edge portions therebetween to define a com¬ partment (11, 31) for the product and at least one of the parts being substantially form-stable to provide the package with the desired shape, characterised in that the sealing seam in the overlapping edge portions and in the portions of the support part (1, 21, 41, 61) and the cover part (8, 28, 48, 68) respectively defining the compartment (11,31) substantially are on right cylindrical surfaces having parallel generators and with the hollowness facing the same side, and that the support part (1, 21, 41, 61) extends such relative to the cover part (8, 28, 48.68) of an adjacent, corresponding package in a stack that it abuts at least said cover part in opposite portions (12, 13) adjacent to its outer ends when seen perpendicular to the generator.

2. A package as claimed in claim 1, characterised in that the cylindrical surface of one of the parts is substantially coincident with the cylindrical surface of the sealing seam.

3. A package as claimed in claims 1 or 2, characterised in that at least the cylindrical portion (22) of the support part is formed of a number of plane faces (34,35).

4. A package as claimed in claim 3, characterised in that the cylindrical portion (22) is formed of two plane faces (34, 35) forming an obtuse angle (v) with each other, preferably an angle of >120°.

5. A package as claimed in claims 1 or 2, characterised in that the cylindrical portion of the support part (1, 41, 61) is a circular cylindrical surface.

6. A package as claimed in one or more of the preceding claims, c h a r a c- t e r i s e d in that the cylindrical portions are symmetrical about a centre plane (CP) perpendicular to the directrices of the cylindrical surfaces.

7. A package as claimed in one or more of the preceding claims, charac¬ terised in that the two cylindrical surfaces are substantially parallel.

5 8. A package as claimed in one or more of the preceding claims, charac¬ terised in that the support part (1, 21) is tray-shaped with a convex bottom wall (2, 22) to support the product and side walls (3, 4, 6; 24, 25, 26) extending upwardly from the bottom wall (2, 22) and continuing at their outer ends into a circumferential, outwardly extending flange (7, 27) connected to the cover part (1, 21).

10 9. A package as claimed in one or more of the claims 1-7, character- is e d in that the cover part (68) is tray-shaped with a convex cover wall (68) to cover the product and side walls (64, 65, 66) extending downwardly from the cover wall (62) and continuing at their lower ends into a circumferential, outwardly extend¬ ing flange (67) connected to the support part (61), said part (61) formed of a support

15 sheet sealed to the flange (67) of the cover part (68).

10. A package as claimed in one or more of the preceding claims, character¬ ised in that the rise (h) ofthe cylindrical surface ofthe support part (1, 21, 41, 61) when measured perpendicular to a plane (SP) through its outer abutment portions (12,13) is higher or equal to 50%, preferably 100% ofthe height (H) ofthe compart-

20 ment (11) at said abutment portions.

11. A package as claimed in one or more of the preceding claims, character¬ ised in that the cover part (8, 28, 48, 68) is made of a transparent material.

12. A package as claimed in one or more of the preceding claims, character¬ ised in that the circumferential sealing seam between the support part (1, 21, 41

25 61) and the cover part (8, 28, 48, 68) is peelable.