Game top type packaging container

Abstract

A method for producing a gable-top paper or paperboard-based packaging container is disclosed, the packaging container having a plurality of upper closure sub-panels, including an upper closure sub-panel (132) configured to form a pour spout of the packaging container when the packaging container is in an open position, the upper closure sub-panel configured to form a pour spout with upper fin panel sections (182 a, 182 b) that are at least partially heat-sealed to one another prior to a first opening of the packaging container, the upper fin panel sections abutting one another within a contact area when the packaging container is in a closed position. The method includes producing a blank (100) from a laminated packaging material having an outer heat-sealable layer, and treating the outer heat-sealable layer in at least one sub-region (192 a, 192 b) of the upper fin panel sections (182 a, 182 b) to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer in the sub-region.

Description

Technical Field

[0001] (Field of the Invention) The present invention relates to a method for producing a gambrel-top paper or cardboard-based packaging container. In particular, the present invention relates to an easily openable gambrel-top packaging container having a gambrel seal, i.e., a gambrel-top packaging container designed to be opened by pushing open and pulling out a gusset panel of the gambrel top to form a pouring spout.

[0002] The present invention also relates to a blank for producing an easily openable gambrel-top paper or cardboard-based packaging container, and a packaging container produced from such a blank.

Background Art

[0003] (Background) Gambrel-top packaging containers, also known as paper packs, are commonly used for distributing pourable products, such as liquid consumer products, such as dairy products like milk, or fruit juices.

[0004] Gambrel-top packaging containers are produced from laminated packaging materials, which typically comprise multiple layers of paper or cardboard sheets, and one or more layers are laminated thereon to hold the pourable product and / or to prevent the transfer of substances that reduce air and flavor through the cardboard. The layers may typically include polyethylene or aluminum layers.

[0005] The laminated packaging material typically also comprises inner and outer heat-sealable layers made, for example, from a thermoplastic polymer.

[0006] In the production of the packaging container, the laminated packaging material may be cut to form a blank, which may be folded, filled, and sealed to form the packaging container.

[0007] To facilitate the bending of the blank, the blank typically comprises a crease line. As is known in the art, a crease line is an embossed or die-cut recess on one side of the cardboard, and on the other side, a corresponding raised portion or welt forms a line, and the cardboard is structurally weakened along the line, and when pressure is applied, the cardboard bends or folds along the line in a controlled manner.

[0008] The sealing of the packaging container is typically effected by heat-sealing a heat sheet adjacent to the heat-sealable layer of the folded panel section, whereby the heat-sealable layer melts and forms an impermeable seam.

[0009] Generally, it is advantageous for the seams thus formed to be as strong as possible. However, in a gable-top type of packaging container designed to be opened by pushing open and pulling out a gable panel to form a pouring spout, an overly strong upper seal makes it difficult for the consumer to open the packaging container without compromising the structural integrity of the laminated packaging material. In particular, when the upper seal is too strong, the laminated packaging material can be easily peeled or partially peeled during the first opening.

[0010] With the above problems in mind, the present disclosure endeavors to propose a new method for producing a gable-top type of packaging container that enables easy opening. Summary of the Invention Means for Solving the Problems

[0011] (Summary of the Invention) With the above problems and known solutions in mind, according to a first exemplary aspect, the present disclosure provides a method for producing a gable-top type of paper or cardboard-based packaging container having a gable seal with an upper fin panel section that is heat-sealed to each other prior to a first opening of the packaging container, the upper fin panel sections being adjacent to each other within a contact region when the packaging container is in a closed position, the method comprising - Producing a blank from a laminated packaging material having an outer heat-sealable layer; - Treating the outer heat-sealable layer within at least one sub-region of the upper fin panel section to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer within the sub-region; and including.

[0012] According to another exemplary aspect, the present disclosure provides a method of producing a gable-top type paper or paperboard-based packaging container having a plurality of upper sealing sub-panels including an upper sealing sub-panel configured to form a spout of the packaging container when the packaging container is in an open position, the upper sealing sub-panel being configured to form a spout comprising an upper fin panel section that is at least partially heat-sealed to each other prior to a first opening of the packaging container, the upper fin panel section being adjacent to each other within a contact region when the packaging container is in a closed position, the method comprising: - Producing a blank from a laminated packaging material having an outer heat-sealable layer; - Treating the outer heat-sealable layer within at least one sub-region of the upper fin panel section to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer within the sub-region; and including.

[0013] The step of treating the outer heat-sealable layer may include coating the sub-region with an adhesive layer. The adhesive layer may be silicon, ink, or any other substance that reduces the bond strength of opposing surfaces during heat-sealing.

[0014] The ratio between the area of the sub-region and the area of the contact region may be in the range of 0.5 to 0.9.

[0015] The step of coating the sub-region may include printing the adhesive layer onto the sub-region.

[0016] The step of printing the adhesive layer may include flexographically printing ink onto the sub-region and UV curing it.

[0017] The step of flexographically printing the adhesive layer may include using a halftone reproduction technique.

[0018] The step of using a halftone reproduction technique may include applying a dot area coverage within the range of 50% to 100% within a sub-region.

[0019] The outer heat-sealable layer is made of LDPE (low density polyethylene), and the step of treating the outer heat-sealable layer may include corona treating the outer heat-sealable layer to a dyn level exceeding any one of 42 dyn / cm, 45 dyn / cm, and 50 dyn / cm and / or to a dyn level within the range of 50 to 60 dyn / cm within a sub-region.

[0020] The step of treating the outer heat-sealable layer within a sub-region of the at least one upper fin panel section may include treating the outer heat-sealable layer within the entire area of the at least upper fin panel section, except within a strip or band bounded by the upper edge of the blank. The strip or band may have a width within the range of 2 mm to 5 mm, i.e., it may extend 2 mm to 5 mm from the upper edge of the blank.

[0021] The method may include - providing an innermost heat-sealable layer within a blank; and - coating at least one section of the innermost heat-sealable layer of an upper sealed sub-panel with an adhesive layer, the adhesive layer reducing or eliminating the heat-sealing ability of the innermost heat-sealable layer within the coating section or sections. and may further include.

[0022] According to a further exemplary aspect, the present disclosure provides a packaging container blank, which is made of a laminated packaging material having an outer heat-sealable layer, and includes a first upper fin panel section and a second upper fin panel section. The first upper fin panel section and the second upper fin panel section are configured to be adjacent to each other within a contact area when the packaging container is in a closed position, and are configured to form a pouring spout when the packaging container is in an open position. The outer heat-sealable layer is processed within a sub-region to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer within at least one sub-region of the upper fin panel section.

[0023] According to a further exemplary aspect, the present disclosure provides a packaging container blank, which is made of a laminated packaging material having an outer heat-sealable layer, and includes a plurality of upper sealed sub-panels including an upper sealed sub-panel configured to form a pouring spout of the packaging container when the packaging container is in an open position. The upper sealed sub-panel includes a first upper fin panel section and a second upper fin panel section configured to be adjacent to each other within a contact area when the packaging container is in a closed position and is configured to form a pouring spout. The outer heat-sealable layer is processed within a sub-region to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer within at least one sub-region of the upper fin panel section.

[0024] In the blank, within the sub-region of at least one upper fin panel section, the outer heat-sealable layer may be processed by coating with an adhesive layer.

[0025] In the blank, the ratio between the area of the sub-region and the area of the contact area may be in the range of 0.5 to 0.9.

[0026] In the blank, the adhesive layer may be printed on the sub-region.

[0027] In the blank, the printed adhesive layer may include ink that is flexographically printed and UV-cured on the sub-region.

[0028] In the blank, the printed adhesive layer may be printed using a halftone reproduction technique. As is known in the art, the halftone reproduction technique involves laying down dots of ink on the printed surface, and the dots vary in size and / or spacing, thus allowing for fine control of the area covered by the ink.

[0029] In the blank, the printed adhesive layer may have a dot area coverage within the range of 50% to 100%.

[0030] In the blank, the outer heat-sealable layer may be made of LDPE, and within the sub-region of at least one upper fin panel section, the outer heat-sealable layer may be corona-treated to a dyn level exceeding any one of 42 dyn / cm, 45 dyn / cm, and 50 dyn / cm, and / or to a dyn level within the range of 50 - 60 dyn / cm.

[0031] In the blank, the outer heat-sealable layer may be treated throughout the entire area of at least the upper fin panel section, except within a strip or band bounded by the upper edge of the blank. The strip or band may have a width within the range of 2 mm to 5 mm, i.e., it may extend 2 mm to 5 mm from the upper edge of the blank.

[0032] The blank may include an innermost heat-sealable layer, and at least one section of the innermost heat-sealable layer of the upper sealing sub-panel may be coated with an adhesive layer that reduces or eliminates the heat-sealing ability of the innermost heat-sealable layer within the coating section or multiple sections.

[0033] According to a further exemplary aspect, the present disclosure provides a gametabletop-type paper or cardboard-based packaging container produced from a blank as disclosed above.

[0034] The preferred and / or optional features of each aspect discussed above can be used alone or in suitable combinations in other aspects of the invention. This specification also provides, for example, the following items. (Item 1) A method for producing a gambrel top type paper or cardboard-based packaging container (300), wherein the packaging container (300) has a plurality of upper sealing sub-panels (130, 132, 134, 136, 138) including an upper sealing sub-panel (132) configured to form a spout (306) of the packaging container (300) when the packaging container (300) is in an open position, the upper sealing sub-panel (132) being configured to form a spout (306) having upper fin panel sections (182a, 182b) that are at least partially heat-sealed to each other prior to a first opening of the packaging container (300), the upper fin panel sections (182a, 182b) being adjacent to each other within a contact area when the packaging container (300) is in a closed position, the method comprising: - producing a blank (100) from a laminated packaging material (200) having an outer heat-sealable layer (208); - treating the outer heat-sealable layer (208) within at least one sub-region (192a, 192b) of the upper fin panel sections (182a, 182b) to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer (208) within the sub-region (192a, 192b); A method comprising the above. (Item 2) The method according to item 1, wherein the step of treating the outer heat-sealable layer (208) includes coating the sub-region (192a, 192b) with an adhesive layer (192a’, 192b’). (Item 3) The method according to item 2, wherein the ratio between the area of the sub-region (192a, 192b) and the area of the contact area is in the range of 0.5 to 0.9. (Item 4) The method according to any one of items 2 and 3, wherein the step of coating the sub-region (192a, 192b) includes printing the adhesive layer (192a’, 192b’) onto the sub-region (192a, 192b). (Item 5) The method according to item 4, wherein the step of printing the adhesive layer (192a’, 192b’) includes flexographically printing ink onto the sub-region (192a, 192b) and UV-curing it. (Item 6) The method according to item 5, wherein the step of flexographically printing the adhesive layer (192a’, 192b’) includes utilizing a halftone reproduction technique. (Item 7) The step of using the halftone copying technique includes applying a dot area coverage within the range of 50% to 100% within the sub-areas (192a, 192b), according to the method of item 6. (Item 8) The outer heat-sealable layer (208) is made of LDPE, and the step of treating the outer heat-sealable layer (208) includes corona treating the outer heat-sealable layer (208) to a dyn level exceeding any one of 42 dyn / cm, 45 dyn / cm, and 50 dyn / cm and / or to a dyn level within the range of 50 - 60 dyn / cm within the sub-areas (192a, 192b) of the at least one upper fin panel section (182a, 182b), according to the method of item 1. (Item 9) The step of treating the outer heat-sealable layer (208) within the sub-areas (192a, 192b) of the at least one upper fin panel section (182a, 182b) includes treating the outer heat-sealable layer (208) over the entire area of the at least upper fin panel section (182a, 182b) except within a strip or band (194a, 194b) bounded by the upper edge (103) of the blank (100), according to any one of the methods of the above items. (Item 10) - providing an innermost heat-sealable layer (206) within the blank (100); - coating at least one section of the innermost heat-sealable layer (206) of the upper sealed sub-panels (130, 132, 134) using an adhesive layer (194, 196, 198), where the adhesive layer (194, 196, 198) reduces or eliminates the heat-sealing ability of the innermost heat-sealable layer (206) within the coated section or sections; including the method according to any one of the above items. (Item 11) A blank (100) for a packaging container (300), made from a laminated packaging material (200) having an outer heat-sealable layer (208), comprising a plurality of upper sealing sub-panels (130, 132, 134, 136, 138) including an upper sealing sub-panel (132) configured to form a spout (306) of the packaging container (300) when the packaging container (300) is in an open position, the upper sealing sub-panel (132) being configured to form a spout (306) having a first upper fin panel section (182a) and a second upper fin panel section (182b), the first upper fin panel section (182a) and the second upper fin panel section (182b) being configured to be adjacent to each other within a contact area when the packaging container (300) is in a closed position, and the outer heat-sealable layer (208) being processed within at least one sub-region (192a, 192b) of the upper fin panel sections (182a, 182b) to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer (208) within the sub-region (192a, 192b). A blank (100) for a packaging container (300). (Item 12) The blank (100) according to item 11, wherein the outer heat-sealable layer (208) is processed by being coated within the sub-regions (192a, 192b) of the at least one upper fin panel section (182a, 182b) using an adhesive layer (192a'192b'). (Item 13) The blank (100) according to item 12, wherein the ratio between the area of the sub-regions (192a, 192b) and the area of the contact area is within the range of 0.5 to 0.9. (Item 14) The blank (100) according to any one of items 12 and 13, wherein the adhesive layer (192a', 192b') is printed on the sub-regions (192a, 192b). (Item 15) The blank (100) according to item 14, wherein the printed adhesive layer (192a', 192b') is flexographically printed on the sub-regions (192a, 192b) and comprises UV-curable ink. (Item 16) The blank (100) according to item 15, wherein the printed adhesive layer (192a', 192b') is printed using a halftone reproduction technique. (Item 17) The blank (100) according to item 16, characterized in that the printed adhesive layer (192a’, 192b’) has a dot area coverage rate within the range of 50% to 100%. (Item 18) The blank (100) according to item 11, characterized in that the outer heat-sealable layer (208) is made of LDPE, and the outer heat-sealable layer (208) is corona-treated within the sub-region (192a, 192b) of the at least one upper fin panel section (182a, 182b) to a dyn level exceeding any one of 42 dyn / cm, 45 dyn / cm, and 50 dyn / cm, and / or to a dyn level within the range of 50 to 60 dyn / cm. (Item 19) The blank (100) according to any one of items 11 to 18, characterized in that the outer heat-sealable layer (208) is treated within the entire area of the at least upper fin panel section (182a, 182b), except within a strip or band (194a, 194b) bounded by the upper edge (103) of the blank (100). (Item 20) The blank (100) according to any one of items 11 to 19, characterized in that the blank (100) is provided with an innermost heat-sealable layer, and at least one section of the innermost heat-sealable layer (206) of the upper sealed sub-panels (130, 132, 134) is coated using an adhesive layer (194, 196, 198), and the adhesive layer (194, 196, 198) reduces or eliminates the heat-sealing ability of the innermost heat-sealable layer (206) within the coating section or multiple sections. (Item 21) A gable-top type paper or paperboard-based packaging container (300) produced from the blank (100) according to any one of items 11 to 20.

Brief Description of the Drawings

[0035] (Description of the Drawings) The following drawings are attached to facilitate the understanding of the present invention.

[0036]

Figure 1

[0037]

Figure 2

[0038]

Figure 3

[0039]

Figure 4

Figure 5

[0040]

Figure 6

[0041]

Figure 7

[0042]

Figure 8

[0043]

Figure 9

[0044] It should be understood that the drawings are not intended to limit the invention to the subject matter depicted therein.

[0045] In the drawings, unless otherwise expressly stated or understood by context, like reference numerals are used to indicate common parts, elements, or features.

Mode for Carrying Out the Invention

[0046] (Detailed Description) In the following, specific embodiments of the blank and the containers produced therefrom will be described in more detail with reference to the drawings. However, the invention defined in the following claims is not limited to the embodiments and examples included herein, but specifically contemplates modified forms of the embodiments that include parts of the embodiments and combinations of elements of different embodiments that are within the scope of the claims.

[0047] An embodiment of a blank 100 according to this specification is disclosed in FIG. 1. The blank 100 is disclosed with a surface configured to form the outer surface of the container facing the viewer.

[0048] The blank 100 is made from a multi-layer paper or cardboard sheet, and one or more barrier layers are laminated on the multi-layer paper or cardboard sheet to perform functions such as holding a pourable product, e.g., a liquid, and / or preventing the transfer of substances that reduce air and flavor through the sheet.

[0049] The blank 100 is generally rectangular and includes a first bottom edge 101, a second upper edge 103, and third and second side edges 105, 107 that are parallel. While the side edges 105 and 107 are generally straight and parallel, the upper and bottom edges 101 and 103 have an irregular shape. The blank 100 also includes a plurality of fold lines that define fold curves, and the blank 100 is configured to be folded along them when formed into a paper pack.

[0050] The blank 100 includes five panels P1 to P5, and the five panels P1 to P5 are partitioned by vertical fold lines 102, 104, 106, and 108 that define fold curves extending across the panel 100 from the bottom edge 101 to the upper edge 103. In this embodiment, the vertical fold lines 102, 104, 106, and 108 are generally straight, parallel, and continuous, i.e., without interruption, and as a result, extend vertically across the blank 100 in a direction between the bottom edge 101 and the upper edge 103, i.e., perpendicular in FIG. 1.

[0051] Each of the panels P1 to P5 includes a first sub-panel 110, 112, 114, 116, 118 that forms a bottom-sealed sub-panel, a second sub-panel 120, 122, 124, 126, 128 that forms a wall-segmented sub-panel, and a third sub-panel 130, 132, 134, 136, 138 that forms an upper-sealed sub-panel. The bottom-sealed sub-panels 110, 112, 114, 116, and 118 are configured to form the bottom seal of the container, and the upper-sealed sub-panels 130, 132, 134, 136, 138 are configured to form the upper seal of the container. The fifth panel P5 is configured to be attached to the inner surface of the first panel P1 adjacent to the side edge 105 when the container is formed.

[0052] The first horizontal fold lines 140 to 148 partition the bottom-sealed sub-panels 110 to 118 from the wall-segmented sub-panels 120 to 128. The fold lines 140 to 148 are generally aligned, that is, arranged alternately, cross the blank 100, and generally extend in the horizontal direction. Similarly, the second horizontal fold lines 150 to 158 partition the wall-segmented sub-panels 120 to 128 from the upper-sealed sub-panels 130 to 138, are generally aligned, cross the blank 100, and generally extend in the horizontal direction.

[0053] The upper fin fold lines 160 to 168 cross the blank 100 and generally extend in the horizontal direction, partitioning the sub-sub-panels 180 to 188 of the upper-sealed sub-panels 130 to 138 from the sub-sub-panels 170 to 178. The sub-sub-panels 180 to 188 form the upper fin panels or seal lips of the blank, the sub-sub-panels 170 and 174 form the roof panels, and the sub-sub-panels 172 and 176 form the gusset panels.

[0054] The gusset panels 172 and 176 each include upper diagonal fold lines 173a, 173b and 177a, 177b respectively, partitioning the gusset panels 172, 176 into gusset panel segments 172a to 172c and 176a to 176c respectively.

[0055] Upper fin panels 182 and 186 each form a gable seal area and are each provided with gable fold lines 183 and 187, which partition upper fin panels 182, 186 into gable seal area segments 182a and 182b, and 186a and 186b, respectively.

[0056] FIG. 2 shows the inner surface of the upper sealed region of blank 100, and the same fold lines, sub-panels, and panel segments are indicated by corresponding reference numerals.

[0057] FIG. 3 shows a schematic cross-sectional view of an embodiment with a packaging laminate 200, and the blank 100 discussed above can be made from the packaging laminate 200.

[0058] The packaging laminate 200 includes a bulk layer 202 of paper or cardboard or other cellulose-based material. The bulk layer 202 may be a multi-layer bulk layer, i.e., it may comprise a plurality of sub-layers having different properties (e.g., different bulk, different fiber composition, etc.). The bulk layer 202 may preferably be any material layer that provides dimensional stability and direct or indirect rigidity to the packaging laminate 200, such as cardboard or paperboard or other cellulose-based material, specifically, of liquid cardboard quality (i.e., such as those used for liquid food packages, aseptic liquid food packages, and retort food packages).

[0059] In FIG. 3, the packaging laminate 200 is oriented to a position intended such that, while not intended that all the illustrated layers above the bulk layer 202 be turned so as to face outward in the packaging container produced from the packaging laminate 200, correspondingly, all the illustrated layers below the bulk layer 202 are turned so as to face inward. In other words, the layers above the bulk layer 202 form the outside of the finished packaging container, and as a result, the layers below the bulk layer 202 in FIG. 2 form the inside of the container while the bulk layer 202 constitutes the central layer at the walls, bottom, and top of the packaging container. For the purpose of facilitating the understanding of the present invention, the expressions “inside” and “outside” are hereinafter adopted as starting from the central bulk layer 202.

[0060] Inside the bulk layer 202, the packaging laminate 200 may comprise a barrier layer 204 arranged to prevent the movement of oxygen and / or substances that reduce flavor through the packaging laminate 200. The barrier layer 204 may be laminated inside the bulk layer 202 and may be adhered to the bulk layer 202 by any method and / or adhesive known in the art. For example, the barrier layer 204 may be laminated to the bulk layer through an intermediate laminate layer (not shown). The barrier layer 204 may include an aluminum foil, a polyamide EVOH barrier layer, a vapor-deposited metallized film, etc. The intermediate laminate layer may be a polyolefin, preferably a thermoplastic material or polymer such as low-density polyethylene, LDPE, etc., but may also be another polyolefin such as polypropylene (suitable for retort packages), or another thermoplastic polymer such as a carboxy group-modified polyolefin such as EAA or EMAA.

[0061] Depending on the contents held by the packaging container, the barrier layer 204 may be omitted.

[0062] The packaging laminate 200 includes an innermost heat-sealable layer 206. The heat-sealable layer 206 serves the purpose of protecting the laminated structure, particularly the bulk layer 202 and the cellulose fibers therein, from moisture originating from the inside of the packaging container. If the barrier layer 204 is present, the heat-sealable layer 206 may be laminated in the same manner. If the barrier layer is omitted, the heat-sealable layer 206 may be laminated inside the bulk layer 202 or adhered otherwise.

[0063] The packaging laminate 200 also includes an outer heat-sealable layer 208. Similar to the innermost heat-sealable layer 206, the outer heat-sealable layer 208 serves the purpose of protecting the laminated structure, particularly the bulk layer 202 and the cellulose fibers therein, from moisture (in this case, moisture originating from the outside of the packaging container). The outer heat-sealable layer 208 may be laminated outside the bulk layer 202.

[0064] The innermost heat-sealable layer 206 and the outer heat-sealable layer 208 may be made of a thermoplastic polymer such as polyethylene (e.g., polyolefin) selected from LDPE (low-density polyethylene), LLDPE (linear low-density polyethylene), mLLDPE (metallocene low-density polyethylene), and any mixture thereof. Alternatively, the heat-sealable layers 206 and 208 may be made of, for example, a heat-sealable polypropylene homopolymer or copolymer suitable for retort packaging.

[0065] Since the innermost heat-sealable layer 206 and the outer heat-sealable layer 208 are intended to protect the bulk layer 202 from moisture, each of the layers 206 and 208 covers the entire inner and outer areas of the packaging laminate 200.

[0066] On the sections of the packaging laminate 200 that form the visible part of the packaging container, typically on the wall section sub-panels 120-126 and the upper sealing sub-panels 130 and 134 (see FIG. 1), the packaging laminate 200 may comprise a decorative layer 210 (for example, a decorative color print such as a printed color pattern optionally including text, nouns, marketing brands, logos, etc.). The decorative layer 210 may be printed, for example, using flexographic printing techniques, on the outside of the outer heat-sealable layer 208. The decorative layer 210 may be produced using a halftone reproduction technique, in which a continuous-tone image is simulated through the use of dots of ink, the dots of ink varying either in size or in spacing and thus being able to produce a tone-like effect. Where the continuous-tone image includes an infinite range of colors or greys, halftoning reduces the visual reproduction of an image printed using only one color of ink at dots of different sizes (pulse-width modulation) or spacing (frequency modulation), or dots where both are different. Color printing can be produced, for example, using the CMYK color model, by repeating halftoning for each primary color of subtractive color mixing.

[0067] As an example, the decorative layer 210 may be laid on the sections of the packaging laminate 200 that form the visible part of the packaging container, using flexographic printing and UV-curable ink (UV flexo ink).

[0068] As is known in the art, the innermost heat-sealable layer 206 and the outer heat-sealable layer 208 are also intended to form seals when the packaging container is produced from a blank. The packaging container is typically produced from a blank in a filling machine by bending the fifth panel P5 relative to the first panel P1 at a longitudinal seam and sealing the panels P1 and P5 (e.g., heat-sealing the outer heat-sealable layer of panel P5 to the corresponding section of the innermost heat-sealable layer of panel P1), thereby creating a tubular sleeve. The sleeve is then bottom-sealed by bending and sealing the bottom-sealing sub-panels 110-118, thereby creating an open-top proto-container. A pourable product that will be held by the container is then filled into the proto-container through the open top, and finally, the top-sealing sub-panels 130-138 are bent and sealed to each other.

[0069] As is known in the art, an upper-sealing proto-container generally involves bringing the seal lips 180-188 into contact with each other, pressing and heating the seal lips, thereby heat-sealing the adjacent heat-sealable layers of the seal lips. In particular, an upper-sealing proto-container generally involves bringing the inner surfaces of the upper fin-panel sections 186a and 182b into contact with the inner surface of the upper fin-panel 184 (see FIG. 2), heat-sealing the adjacent sections of the innermost heat-sealable layers of the upper fin-panel 184 and the upper fin-panel sections 186a and 182b, and correspondingly, bringing the inner surfaces of the upper fin-panel sections 182a and 186b into contact with the inner surface of the upper fin-panel 180 (and the inner surface of the intervening upper fin-panel 188), and heat-sealing the adjacent sections of the innermost heat-sealable layers of the upper fin-panel 180 (and the intervening upper fin-panel 188') and the upper fin-panel sections 182a and 186b.

[0070] Furthermore, the upper seal involves bringing the outer surfaces of the upper fin panel sections 182a and 182b into contact with each other, heat-sealing adjacent sections of the outer heat-sealable layers of the upper fin panel sections 182a and 182b, and correspondingly, bringing the outer surfaces of the upper fin panel sections 186a and 186b into contact with each other and heat-sealing adjacent sections of the outer heat-sealable layers of the upper fin panel sections 186a and 186b.

[0071] When the upper fin panel and the panel sections are brought into contact with each other, they form upper fins, and the upper seal can be achieved by pressing and heating the upper fins, for example, in a suitable pressing and heating tool such as a die (not shown).

[0072] FIG. 7 is a perspective view of a packaging container 300 including a gable seal 302 and a sealed upper fin 304.

[0073] Referring to FIGS. 8 and 9, opening the packaging container 300 generally involves a first step of breaking the seal formed between the outer surfaces of the upper fin panel sections 182a and 182b (see FIGS. 1 and 8), followed by a second step of breaking the seals formed between the upper fin panel 184 and the inner surface of the upper fin panel section 182b, and between the upper fin panel 180 and the inner surface of the upper fin panel section 182a, respectively (see FIGS. 2 and 9).

[0074] The upper fin panel sections 182a and 182b are identical, that is, they are the same in size and shape. As a result, when the packaging container 300 is in the closed position, the upper fin panel sections 182a and 182b are adjacent to each other within contact areas generally corresponding to the areas of the upper fin panel sections 182a and 182b.

[0075] At the opening position of the packaging container 300 (see FIG. 9), the upper sealing sub-panel 132 (see FIGS. 1 and 9) forms the pouring spout 306 of the packaging container 300. In particular, the inner surfaces of the upper fin panel sections 182a and 182b form the pouring lip of the pouring spout 306.

[0076] According to the present invention, the opening force required in the first step is reduced by treating the outer heat-sealable layer 208 in at least one sub-region of the upper fin panel sections 182a and 182b to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer 208 in the sub-region.

[0077] FIG. 4 shows an embodiment with a blank, and the outer heat-sealable layer 208 in the sub-region 192b of the upper fin panel section 182b is treated to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer 208 in the sub-region 192b. The outer heat-sealable layer 208 in the upper fin panel section 182a is untreated. However, only the outer heat-sealable layer 208 in the upper fin panel section 182a can produce an effective heat seal with the untreated portion of the outer heat-sealable layer 208 in the upper fin panel section 182b (i.e., in this embodiment, within the strip 194b bounded by the upper edge 103).

[0078] FIG. 5 shows an embodiment in which the outer heat-sealable layer 208 in the sub-region 192a of the upper fin panel section 182a is also treated to reduce or eliminate the heat-sealing ability of the heat-sealable layer 208. In this embodiment, the sub-regions 192a and 192b are congruent, and as a result, the upper fin panel sections 182a and 182b overlap when folded against each other.

[0079] Generally, the area covered by the sub-region or sub-regions to be processed preferably covers 50% to 90% of the area of the contact region between the upper fin panel sections 182a and 182b. In other words, the ratio of the area of the sub-region or sub-regions to the area of the contact region formed between the upper fin panel sections 182a and 182b should preferably be within the range of 0.5 to 0.9.

[0080] According to one embodiment, the outer heat-sealable layer 208 throughout the upper fin panel sections 182a and 182b is treated to reduce or eliminate heat-sealing ability, except for the narrow strips or bands 194a, 194b bounded by the upper edge 103. This allows the upper fin panel sections 182a and 182b to be heat-sealed to each other along the strips or bands 194a, 194b, but prevents or at least reduces heat-sealing in the remaining portion of the contact region formed between the upper fin panel sections 182a and 182b. In one embodiment, the strips or bands 194a, 194b may have a width within the range of 2 mm to 5 mm, i.e., it may extend 2 mm to 5 mm from the upper edge 103.

[0081] According to one embodiment, the treatment of the sub-regions 192a and / or 192b may include coating the sub-regions 192a and / or 192b with an adhesive layer, such as silicon. This effectively prevents the outer heat-sealable layer 208 of the upper fin panel sections 182a and 182b from forming heat-seals within the sub-regions 192a and / or 192b.

[0082] According to another embodiment, the treatment of sub-region 192a and / or 192b may include printing an adhesive layer on the sub-region or sub-regions, for example, flexographically printing UV curable ink on sub-region 192a and / or 192b. The same ink as that applied to the decorative layer 210 may be printed on sub-region 192a and / or 192b. This enables sub-region 192a and / or 192b to be processed at the same processing station where the decorative layer 210 is printed on the blank.

[0083] The halftone reproduction technique can be advantageously applied when flexographically printing the adhesive layer. This enables the heat sealing ability of the upper fin panel sections 182a and 182b to be precisely controlled because the technique allows for fine control of the coverage of the dot area. The dot area coverage may be, for example, in the range of 50% to 100%. A 50% dot area coverage implies that 50% of the printed area is covered by the adhesive material, for example, UV curable ink, and thus reduces the heat sealing ability of the printed area by approximately 50% (compared to the non-printed area). A 100% dot area coverage implies that the entire printed area is covered by the adhesive material and thus effectively eliminates heat sealing within the printed area.

[0084] As an alternative to coating sub-region 192a and / or 192b with an adhesive material, sub-region 192a and / or 192b may be subjected to a corona treatment. Corona treatment (sometimes also referred to as air plasma treatment) is a surface modification technique that uses low-temperature corona discharge plasma to impart changes in the surface properties, particularly the surface energy. It has been found that corona treating the heat sealable layer to a dyn level exceeding approximately 42 dyn / cm can reduce the heat sealing ability of the outer heat sealable layer 208 with respect to LDPE, which is a material commonly used in the heat sealable layer.

[0085] Corona plasma can be generated by applying a high voltage to an electrode having a sharp tip, and the plasma is formed at the tip thereof. According to one embodiment, the laminated packaging material may be passed through such a tip in order to change the surface energy of the outer heat-sealable layer 208 within sub-region 192a and / or 192b. The dyne level of the outer heat-sealable layer 208 is caused to exceed 42 dynes / cm, more preferably to exceed 45 dynes / cm, and even more preferably to exceed 50 dynes / cm. According to one embodiment, the outer heat-sealable layer within sub-region 192a and / or 192b is corona-treated to a dyne level within the range of 50 to 60 dynes / cm.

[0086] The opening force required in the second opening step, i.e., the step of breaking the heat seal formed between the inner surfaces of the upper fin panel 184 and the upper fin panel section 182b and between the inner surfaces of the upper fin panel 180 and the upper fin panel section 182a (see FIGS. 2 and 9), can be reduced by coating the sections of the innermost heat-sealable layer 206 (see FIG. 3) of the upper sealed sub-panels 130, 132, and / or 134 with an adhesive layer, such as silicon. Examples of such adhesive layers 194, 196, 198 are shown in FIG. 6. Providing ease of opening in this manner is known as such and will not be discussed in detail here. However, the provision of ease of opening according to the present invention, i.e., the provision of ease of opening in the first opening step, is also beneficial for the second opening step. In particular, without wishing to be bound by theory, it is believed that in the first opening step, i.e., when breaking the heat seal between the outer surfaces of the upper fin panel sections 182a and 182b (see FIG. 1), the structural integrity of the packaging laminate 200 is protected by providing ease of opening. This, in turn, reduces the risk of failure in the second opening step without compromising the structural integrity of the packaging laminate, for example, by peeling or partially peeling the packaging material 200, and increases the likelihood of correctly breaking the heat seals between the upper fin panel 184' and the inner surface of the upper fin panel section 182b and between the upper fin panel 180' and the inner surface of the upper fin panel section 182a, respectively.

[0087] It will be understood that certain features of the invention that have been described above in the context of separate embodiments for clarity may also be provided in combination within a single embodiment. Conversely, various features of the invention that have been described above in the context of a single embodiment for brevity may also be provided separately or in any suitable sub-combination.

[0088] In the foregoing description, various aspects of the blanks and containers according to this specification have been described with reference to exemplary embodiments. For purposes of explanation, specific numbers, systems, and configurations have been set forth in order to provide a thorough understanding of the apparatus and its operation. However, the description is not intended to be construed in a limiting sense. Various modifications and variations of the exemplary embodiments, as well as other embodiments of the apparatus that will be apparent to those of ordinary skill in the art to which the disclosed subject matter pertains, may be within the scope of the invention as defined by the following claims.

Claims

1. A method of producing a gambrel-top paper or cardboard-based packaging container (300), said packaging container (300) having a plurality of upper sealing sub-panels (130, 132, 134, 136, 138) including an upper sealing sub-panel (132) configured to form a spout (306) of said packaging container (300) when said packaging container (300) is in an open position, said upper sealing sub-panel (132) being configured to form a spout (306) comprising upper fin panel sections (182a, 182b) that are at least partially heat-sealed to each other prior to a first opening of said packaging container (300), said upper fin panel sections (182a, 182b) being adjacent to each other within a contact area when said packaging container (300) is in a closed position, said method comprising: - producing a blank (100) from a laminated packaging material (200) having an outer heat-sealable layer (208); - treating the outer heat-sealable layer (208) within at least one sub-region (192a, 192b) of said upper fin panel sections (182a, 182b) to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer (208) within said sub-region (192a, 192b); comprising, said step of treating the outer heat-sealable layer (208) comprising coating said sub-region (192a, 192b) with an adhesive layer (192a', 192b'); said step of coating said sub-region (192a, 192b) comprising printing said adhesive layer (192a', 192b') onto said sub-region (192a, 192b); said step of printing said adhesive layer (192a', 192b') comprising flexographically printing ink onto said sub-region (192a, 192b) and UV-curing, a method.

2. The method according to claim 1, wherein the ratio between the area of said sub-region (192a, 192b) and the area of the contact area is in the range of 0.5 to 0.

9.

3. The method according to any one of claims 1 and 2, wherein said step of flexographically printing said adhesive layer (192a', 192b') comprises utilizing a halftone reproduction technique.

4. The step of utilizing the halftone copying technique includes applying a dot area coverage within a range of 50% to 100% within the sub-regions (192a, 192b), the method according to claim 3.

5. The outer heat sealable layer (208) is made of LDPE, and the step of treating the outer heat sealable layer (208) includes corona treating the outer heat sealable layer (208) within the sub-regions (192a, 192b) to a dyn level exceeding any one of 42 dyn / cm, 45 dyn / cm, and 50 dyn / cm, and / or to a dyn level within a range of 50 to 60 dyn / cm, the method according to claim 1.

6. The step of treating the outer heat sealable layer (208) within the sub-regions (192a, 192b) of the at least one upper fin panel section (182a, 182b) includes treating the outer heat sealable layer (208) within the entire area of the at least upper fin panel section (182a, 182b) except within strips or bands (194a, 194b) bounded by the upper edge (103) of the blank (100), the method according to any one of claims 1 to 5.

7. - providing an innermost heat sealable layer (206) within the blank (100); - coating at least one section of the innermost heat sealable layer (206) of the upper sealed sub-panels (130, 132, 134) using an adhesive layer (194, 196, 198), wherein the adhesive layer (194, 196, 198) reduces or eliminates the heat sealing ability of the innermost heat sealable layer (206) within the coated section; including the method according to any one of claims 1 to 6.

8. A packaging container (300) blank (100) made from a laminated packaging material (200) having an outer heat-sealable layer (208), comprising a plurality of upper sealing sub-panels (130, 132, 134, 136, 138) including an upper sealing sub-panel (132) configured to form a spout (306) of the packaging container (300) when the packaging container (300) is in an open position, the upper sealing sub-panel (132) being configured to form a spout (306) comprising a first upper fin panel section (182a) and a second upper fin panel section (182b), the first upper fin panel section (182a) and the second upper fin panel section (182b) being configured to be adjacent to each other within a contact area when the packaging container (300) is in a closed position, and the outer heat-sealable layer (208) being processed within at least one sub-region (192a, 192b) of the upper fin panel sections (182a, 182b) to reduce or eliminate the heat-sealing ability of the outer heat-sealable layer (208) within the sub-region (192a, 192b). The outer heat-sealable layer (208) is processed by being coated within the sub-regions (192a, 192b) of the at least one upper fin panel section (182a, 182b) using an adhesive layer (192a' 192b'). The adhesive layer (192a', 192b') is printed on the sub-regions (192a, 192b). A packaging container (300) blank (100), wherein the printed adhesive layer (192a', 192b') is flexographically printed on the sub-regions (192a, 192b) and comprises an ink that is UV-cured.

9. The blank (100) according to claim 8, characterized in that the ratio between the area of the sub-regions (192a, 192b) and the area of the contact area is within the range of 0.5 to 0.

9.

10. The blank (100) according to any one of claims 8 and 9, characterized in that the printed adhesive layer (192a', 192b') is printed using a halftone reproduction technique.

11. The blank (100) according to claim 10, characterized in that the printed adhesive layer (192a', 192b') has a dot area coverage within the range of 50% to 100%.

12. The outer heat-sealable layer (208) is made of LDPE, and the outer heat-sealable layer (208) is corona-treated within the sub-regions (192a, 192b) of the at least one upper fin panel section (182a, 182b) to a dyn level exceeding any one of 42 dyn / cm, 45 dyn / cm, and 50 dyn / cm, and / or to a dyn level within the range of 50 to 60 dyn / cm. The blank (100) according to claim 8.

13. The outer heat-sealable layer (208) is processed within the entire area of the at least upper fin panel section (182a, 182b), except within strips or bands (194a, 194b) bounded by the upper edge (103) of the blank (100). The blank (100) according to any one of claims 8 to 12.

14. The blank (100) is provided with an innermost heat-sealable layer (206), and at least one section of the innermost heat-sealable layer (206) of the upper sealed sub-panels (130, 132, 134) is coated using an adhesive layer (194, 196, 198), and the adhesive layer (194, 196, 198) reduces or eliminates the heat-sealing ability of the innermost heat-sealable layer (206) within the coated section. The blank (100) according to any one of claims 8 to 13.

15. A gable-top type paper or paperboard-based packaging container (300) produced from the blank (100) according to any one of claims 8 to 14.

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