Method of Producing a Packaging Container and a Packaging Container

Abstract

A method of forming a paperboard packaging container from a rectangular body blank is disclosed, the method including the following steps: a) providing a rectangular body blank made from a laminate sheet material; b) forming a tubular container body from the rectangular body blank, the container body having a first end with a first body opening and a second end with a second body opening; c) sealing together the first and the second side edge in a but-to-but seal using a sealing strip having a sealing strip width; d) presenting the tubular container body to a crease line forming station; e) closing the second body opening by pressing a paperboard disc into the second body opening; f) forming a curled second edge by folding or rolling the second end of the container body wall inwardly; g) filling the packaging container with bulk solids; and h) closing the first body opening.

Claims

1. A method of forming a paperboard packaging container from a rectangular body blank, the method comprising the steps of: a) providing a rectangular body blank, the body blank having a longitudinal direction and a transverse direction, the body blank having a first transverse edge and a second transverse edge and a first and a second side edge, an inside surface and an outside surface, the body blank being made from a laminate sheet material comprising a carton substrate layer, the body blank comprising two or more parallel crease lines, the parallel crease lines extending along the second transverse edge between respective first and second line end points, the respective first line end points each being arranged with a distance (d.sub.1) of from 2 mm to 15 mm from the first side edge and the respective second line end points each being arranged with a distance (d.sub.2) of from 2 mm to 15 mm from the second side edge; b) forming a tubular container body from the rectangular body blank, the container body having a first end with a first body opening and a second end with a second body opening and a container body wall extending in a height direction of the packaging container between the first body opening and the second body opening, the height direction of the packaging container corresponding to the longitudinal direction of the body blank, the container body wall having an inner surface and an outer surface, a first end edge and a second end edge; c) sealing together the first and the second side edge in a but-to-but seal using a sealing strip having a sealing strip width, the sealing strip extending over a non-creased area bridging the first and the second side edge and extending between the first and second end points of the two or more parallel continuous crease lines, as seen in a circumferential direction of the paperboard packaging container corresponding to the transverse direction for the body blank; d) presenting the tubular container body to a crease line forming station and providing the non-creased area bridging over the sealing strip and extending between the respective first and second end points with two or more bridging crease lines such a that a bridging crease line area is formed, extending in the circumferential direction; e) closing the second body opening by pressing a paperboard disc into the second body opening, the paperboard disc having a peripheral flange being flexed towards the second end in the height direction of the paperboard packaging container and sealing the peripheral flange of the paperboard disc to the inner surface of the container wall; f) forming a curled second edge by curling the second end of the container body wall inwardly, at the two or more parallel crease lines and at the crease line area, the curled second edge comprising an edge portion and an inner portion; g) filling the packaging container with bulk solids; h) closing the first body opening; i) wherein steps h) and subsequently step g) could alternatively come after step d).

2. The method of forming a paperboard packaging container according to claim 1, wherein the two or more parallel crease lines provided in the body blank in step a) are three or more parallel continuous crease lines and wherein the two or more bridging crease lines in step e) are three or more bridging crease lines forming the bridging crease line area.

3. The method of forming a paperboard packaging container according to claim 1, wherein step f) includes folding or rolling the second end of the container body wall inwardly and over the peripheral flange of the paperboard disc.

4. The method of forming a paperboard packaging container according to claim 1, wherein the inner portion has a height (h.sub.1) of from 2 mm to 20 mm, as measured between the second transverse edge of the body blank and the edge portion.

5. The method of forming a paperboard packaging container according to claim 1, wherein a distance between adjacent crease lines of the two or more parallel crease lines is between 0.5 and 4 mm, as seen in the height direction.

6. The method of forming a paperboard packaging container according to claim 1, wherein a distance between adjacent bridging crease lines of the two or more parallel bridging embossed lines is between 0.5 and 4 mm, as seen in the height direction.

7. The method of forming a paperboard packaging container according to claim 1, wherein the second transverse edge is a bottom edge, the second body opening is a bottom body opening, the second end edge is a bottom end edge, the paperboard disc is a bottom disc and the curled second edge is a curled bottom edge.

8. The method of forming a paperboard packaging container according to claim 1, wherein the second transverse edge is an upper edge, the second body opening is an upper body opening, the second end edge is an upper end edge, the paperboard disc is a top disc and the curled second edge is a curled upper edge.

9. The method of forming a paperboard packaging container according to claim 1, wherein the body blank in step a) furthermore is provided with two or more parallel crease lines extending along the first transverse edge between respective third and fourth line end points, the respective third line end points each being arranged with a distance of from 2 mm to 15 mm from the first side edge and the respective fourth line end points each being arranged with a distance of from 2 mm to 15 mm from the second side edge; and wherein step d) includes providing a second non-creased area bridging over the sealing strip and extending between the respective third and fourth line end points of the two or more parallel crease lines extending along the first transverse edge with two or more bridging crease lines such that a second bridging crease line area is formed, wherein step h) includes closing the first body opening by pressing a paperboard disc into the first body opening, the paperboard disc having a peripheral flange being flexed towards the first end in the height direction of the paperboard packaging container and sealing the peripheral flange of the paperboard disc to the inner surface of the container wall; the method further including a step of forming a curled first edge by curling the first end of the container body wall inwardly, at the two or more parallel crease lines arranged along the first transverse edge.

10. A paperboard packaging container for bulk solids, the container comprising a tubular container body, a container bottom and a container lid, the container body extending in a height direction of the container from a first end to a second end, the tubular container body comprising a container body wall, the container body wall having an inner surface facing towards an inner compartment in the packaging container and an outer surface facing away from the inner compartment, a first end edge and a second end edge, the tubular container body being made by a laminate sheet material comprising a carton substrate layer, and comprises a but-to-but joint extending in the height direction, the but-to-but joint being sealed by a sealing strip, a second body opening being closed with a paperboard disc having a peripheral flange being flexed towards the second end in the height direction and attached to the inner surface of the container body wall, the second end of the container body wall being curled inwardly providing a curled second edge comprising an edge portion and an inner portion characterized in that the container wall at the curled second edge and along a circumference of the tubular container body is provided with two or more parallel crease lines connected over a bridging area with two or more bridging parallel creased lines, the bridging area bridging over the sealing strip, such that the two or more parallel crease lines and the two or more bridging crease lines extend in a circumferential direction around the circumference of the tubular container body.

11. The paperboard packaging container according to claim 10, wherein the inner portion of the curled second edge has a height (h.sub.1) of from 2 mm to 20 mm as measured from the edge portion to an end edge of the inner portion.

12. The paperboard packaging container according to claim 10, wherein the two or more circumferential and parallel crease lines are three or more circumferential and parallel crease lines and wherein the two or more bridging crease lines are three or more bridging crease lines.

13. The paperboard packaging container according to claim 10, wherein a distance between the circumferential and parallel crease lines are between 0.5 and 4 mm, as seen in the height direction and as measured between two adjacent crease lines.

14. The paperboard packaging container according to claim 10, wherein the second body opening is a bottom body opening, the second end edge is a bottom end edge, the paperboard disc is a bottom disc and the curled second edge is a curled bottom edge.

15. The paperboard packaging container according to claim 10, wherein the second body opening is an upper body opening, the second end edge is an upper end edge, the paperboard disc is a top disc and the curled second edge is a curled top edge.

16. The paperboard packaging container according to claim 10, wherein the first end of the container body wall is curled inwardly providing a curled first edge comprising an edge portion and an inner portion characterized in that the container wall at the curled first edge and along a circumference of the tubular container body is provided with two or more parallel crease lines connected over a second bridging area with two or more bridging parallel crease lines, the second bridging area bridging over the sealing strip, such that the two or more parallel crease lines and the two or more bridging crease lines extend in a circumferential direction around the circumference of the tubular container body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The present invention will be further explained hereinafter by means of non-limiting examples and with reference to the appended drawings wherein:

[0063] FIGS. 1a-1g illustrate steps in a method of forming a packaging container according to the present disclosure;

[0064] FIG. 2 illustrates a packaging container according to the present disclosure.

DETAILED DESCRIPTION

[0065] It is to be understood that the drawings are schematic and that individual components, such as layers of materials are not necessarily drawn to scale. The steps in the method of forming a packaging container and the packaging container shown in the figures are provided as examples only and should not be considered limiting to the invention. Accordingly, the scope of invention is determined solely by the scope of the appended claims.

[0066] FIGS. 1a-1g illustrate a method of forming a packaging container 1 according to the present disclosure. FIG. 1a illustrates a rectangular body blank 2 having a longitudinal direction L and a transverse direction T. The body blank 2 has a top edge 3 and a bottom edge 4 and a first and a second side edge 5, 6, an inner surface 7 and an outer surface 8. The parallel crease lines 9 extend between respective first and second line end points 10, 11. The respective first line end points 10 are each arranged with a distance d.sub.1 of from 2 mm to 15 mm from the first side edge 5 and the respective second line end points 11 are each arranged with a distance d.sub.2 of from 2 mm to 15 mm from the second side edge 6. The method involves bending the rectangular paperboard body blank 2 shown into a tube 12 by bending together side edges 5, 6 of the paperboard sheet material 2, thus causing the material to assume a tubular shape as shown in FIG. 1b. The tube forming the tubular container body 12 has an upper end 13 with an upper body opening 14 and a bottom end 15 with a bottom body opening 16 and a container body wall 17 extending in a height direction H of the packaging container 1 between the upper body opening 14 and the bottom body opening 16. The container body wall 17 has an inner surface 18 and an outer surface 19, an upper end edge 20 and a bottom end edge 21. The side edges 5, 6 of the paperboard sheet material 2 are arranged in a but-to-but relationship. Between the respective first and second end points 10, 10′, 10″, 11, 11′, 11″ there is a non-creased area 23 bridging over the side edges 5, 6 of the paperboard sheet material 2. The container wall 17 is provided with three continuous and parallel crease lines 9,9′,9″. The three parallel crease lines each extend between their respective first and second end points 10, 10′, 10″, 11, 11′, 11″, the first end points 10, 10′, 10″ being provided with a distance d.sub.1 from the first side edge 5 and the second end points 11, 11′, 11″ being provided with a distance d.sub.2 from the second side edge 6. The first and the second distance d.sub.1, d.sub.2 being of from 2 mm to 15 mm. The first and the second distance d.sub.1, d.sub.2 may be the same or may differ from each other.

[0067] In FIG. 1c, the side edges 5, 6 of the paperboard body blank 2 is sealed in a but-to-but seal using a sealing strip 22 to form the tubular container body 12. The sealing strip 22 has a sealing strip width w.sub.s, the sealing strip width w.sub.s corresponding essentially to the width of the non-creased area 23, i.e. d.sub.1+d.sub.2, and thus extends, in a width direction, between the respective first and second end points 10, 10′, 10″, 11, 11′, 11″, of the three continuous crease lines 9,9′,9″. The distance d.sub.1 may, as illustrated in the figures herein, be the same for each of the first end points 10, 10′, 10″ and the distance d.sub.2 may equally be the same for each of the first end points 10, 10′, 10″.

[0068] In FIG. 1d, the tubular container body 12 is presented to an embossing station 24 and the non-creased area 23 which is bridged by the sealing strip 22 and extending between the respective first and second end points 10, 10′, 10″, 11, 11′, 11″ is provided with bridging embossing lines 21, in this figure three bridging embossing lines 21, 21′, 21″, such that a bridging crease line area 25 is formed. The three bridging embossing lines 21, 21′, 21″ extend in a circumferential direction C, corresponding to the transverse direction T of the body blank. In FIG. 1d, the three bridging embossing lines 21, 21′, 21″ are aligned with the three crease lines 9,9′,9″, thus forming three closed loops.

[0069] In FIG. 1e, the bottom body opening 16 is closed by pressing a bottom disc 26 into the bottom body opening 16. The bottom disc 26 has a peripheral flange 27 being flexed towards the bottom end 15 in the height direction H of the paperboard packaging container 1. Subsequently, the peripheral flange 27 of the bottom disc 26 is sealed to the inner surface 18 by means of high frequency welding. The bottom disc 26 is inserted such that the bottom disc 26 including the peripheral flange is arranged closer to the upper end 13 of the tubular container body 12 as compared to the parallel crease lines 9,9′,9″.

[0070] In FIG. 1f a curled bottom edge 28 is formed by folding or rolling the bottom end 15 of the container body wall 17 inwardly at the parallel crease lines 9,9′,9″ and at the bridging crease line area 25. The curled bottom edge 28 comprises an edge portion 28a and an inner portion 28b as illustrated in FIG. 1g. The packaging container 1 may in a subsequent step, not illustrated in the figures, be filled with bulk solids into the tubular container body 12 via the upper body opening 14. In a further step the upper body opening 14 is closed. The upper body opening 14 may for example in a first step be closed by pressing a paperboard top disc into the tube 12 at the upper end 13, the top disc having a peripheral flange being flexed towards the upper end 13 in the height direction H. The upper body opening 14 may alternatively or additionally be closed by applying a lid component to the upper end 13 of the tubular container body 12.

[0071] The method illustrated in FIGS. 1a to 1 g illustrates forming a packaging container having a curled bottom edge, however the method may alternatively or additionally be providing a packaging container having a curled upper edge and wherein the tubular container body is provided with two or more parallel crease lines and a bridging crease line area including two or more bridging crease lines at the curled upper edge.

[0072] In FIG. 2, a paperboard packaging container 1 according to the present disclosure is shown. The packaging container 1 comprising a tubular container body 12, a container bottom 30 and a container lid 31. The container body 12 extends in a height direction H of the packaging container 1 from an upper end 13 to a bottom end 15. The tubular container body 12 comprises a container body wall 17. The container body wall 17 has an inner surface 18 facing towards an inner compartment 29 in the packaging container 1 and an outer surface 19 facing away from the inner compartment 29. The container body wall 17 has an upper end edge 20 and a bottom end edge 28. The tubular container body 12 comprises a but-to-but joint extending in the height direction H, the but-to-but joint being sealed by a sealing strip 22, see FIG. 1b. The container bottom 30 comprises a bottom disc 26 having a peripheral flange 27 being flexed towards the bottom end 15 in the height direction H and attached to the inner surface 18 of the container body wall 17. The second end 15, herein in the form of the bottom end 15 of the container body wall 17 has been curled or rolled inwardly to provide a curled bottom edge 28 comprising an edge portion 28a and an inner portion 28b. The inner portion 28b of the curled bottom edge 28 may have a height h.sub.1 of about from 2 to 20 mm. The height h.sub.1 is measured from the bottom edge of the body blank bottom edge 4 and to the edge portion 28a. The container wall 17 is provided with three circumferential and parallel crease lines 9,9′,9″ including a bridging area at the curled bottom edge 28. The three circumferential crease lines 9,9′,9″ are connected in a bridging crease line area 25 comprising three bridging parallel crease lines 21, 21′, 21″ bridging over the sealing strip 22, see FIG. 1d, such that the parallel crease lines 9, 21 extend continuously in a circumferential direction C around the circumference of the tubular container body 17. The packaging container 1 disclosed in FIG. 2 is provided with a partly or fully removable transport closure 32 being attached to the inner surface 18 of the container body wall 17. The transport closure 32 may be attached to the inner surface 18 of the container body wall 17 by means of a flexed peripheral edge portion 32a extending the height direction H of the paperboard packaging container 1. The lid 31 may be of the plug-in lid typ, comprising an outer circumferential lid collar 33 having a lid abutment edge 34, adapted to abut against a container body abutment edge 35, and a lid plug-in portion 36. An example of this kind of lid-type is disclosed in WO 2017/180056. The paperboard packaging container as disclosed in FIG. 2 is provided with a first curled edge 20, here a curled upper edge 20. The container wall 17 is provided with three circumferential crease lines 109, 109′, 109″. The container wall furthermore comprises a second bridging area comprising three bridging parallel crease lines bridging over the sealing strip 22 (not shown in the figure). The first curled edge 20 comprises an edge portion 20a and an inner portion 20b. Moreover, the lid may be of the removable kind, without any permanent connection to the container body. It is further to be understood that the closure arrangement as shown in FIG. 2 is non-limiting and that the bottom end as disclosed herein may be used for packaging containers having other types of closure arrangements such as closure arrangements wherein a lid cooperates with a reinforcement rim or with a frame structure of the container body to close and open the packaging container. The lid may be provided as a part of a lid component. A lid component comprises a rim to which the lid is connected with a hinge. The rim is attached to the container body and stabilizes the container opening. The lid component may be provided with features such as locking means for keeping the lid in a closed position, tamper evidence means, stacking means, etc. as known in the art. Lid components are usually formed by injection molding of thermoplastic material.