CN1997567B - Blank, container and method for enhancing liquid inclusions into closed containers - Google Patents

Abstract

A container formed from a paperboard laminate and including a rupturable opening for gaining access to the contents of the container, the opening being defined by an embossment pattern in a wall of the container. The embossment defines a weakened area which includes the layers of the laminate, but without destruction or deterioration of selected ones of the barrier/sealing layers of the laminate. A method is disclosed.

Description

Blank, container and method for enhancing liquid inclusions into closed containers

technical field

The present invention relates to a rupturable opening for accessing the contents of a closed (sealed) container and a method of forming the same.

Background technique

Liquid foods are generally served to consumers contained in closed (sealed) containers constructed of laminated sheets comprising a paperboard base having at least one or more outer barrier layers. This barrier layer separates the paperboard from moisture originating from inside or outside the container. Sometimes, barrier layer(s) further impede or reduce gas transfer through the vessel wall. The outer layer may sometimes include a heat seal layer, which may also serve a barrier function.

Access to the contents of the container is usually provided by inserting a common drinking straw into an opening defined in the wall at the top of the container. Such regions have previously taken many forms, such as multiple slits emanating from a central point and extending partially or completely through the wall of the container, partial perforations through the wall of the container, or other techniques. Most commonly, such an area is delimited using a cut partly through the thickness of the container wall, thus allowing the area to be ruptured, for example using a common drinking straw, thus gaining access to the interior of the container. Likewise, the prior art includes techniques for providing slits or cuts through most or all of the thickness of the container wall, and these slits or cuts are temporarily sealed with removable flaps, covers, or flaps of the container.

It should be noted that in the industry there are containers for food such as milk, where the container is a geometry of a cup with a lid. However, in some of these containers, the opening for accessing the contents of the container is located at the bottom of the container, the end of the container opposite the lid. In this disclosure, the term "top wall" of a container will be interpreted as referring to the wall of the container through which access to the contents of the container is achieved through the use of the openings disclosed herein. Thus, in the aforementioned covered cup, the "top wall" of such a container would include the actual bottom wall of the cup.

These prior art techniques of weakening the walls of the container to allow the insertion of straws, for example, suffer from various problems. Clearly, unsealed full cuts through the thickness of the vessel wall are not permitted. Weakening the region of the container wall by cutting partly through the thickness of the wall requires precise cutting of the blank that will eventually form the container. Known commercial manufacturing equipment for this purpose has been found to be unreliable in making such partial thickness cuts. This unreliability can be compounded by the thickness of the laminate being notched, among other factors.

Attempts have been made in the prior art to create areas of weakness in container walls by embossing patterns in the container walls. In particular containers formed from paperboard laminates and intended to hold liquids, it is permissible for the layers of the laminate to One or more layers, but less than all layers, break in the process of defining the opening for future access to the contents of the container. This is true for liquids with a short shelf life such as milk. For other liquids Containers such as orange juice do not allow the liquid in the container to enter the fibers of the paperboard substrate of the laminate. It has now been found that known embossing patterns and techniques for their manufacture result in lamination to one or both of the opposing surfaces of the paperboard substrate The outer layer of the barrier or sealing material on the container ruptures, thus exposing the absorbent fibers of the cardboard to draw liquid from the inside of the container, or liquid from the outside of the container, either of which can damage the laminate holding the container in the container The ability to contain, or allow inadvertent piercing of a weakened area of the container wall. In more serious cases, leakage of the container contents in any such case can lead to impairment of the purity, taste, etc. of the container contents. While , as indicated, rupture of one or more barrier or sealing layers of paperboard laminates used to form liquid containers is permitted in certain containers, while rupture of such layers is not permitted in other liquid containers. It has been found that the Known prior art techniques for embossing patterns lack the ability to consistently provide areas of weakness in the walls of liquid containers using paperboard laminates that are critical to retaining the contents in the container and/or protecting the container contents from the container. Inclusions remain intact to the extent required by undesired changes and can still be broken easily with common straws.

Contents of the invention

In accordance with the present invention, a modified rupturable region is provided in the container wall for optional access to the contents of the container, the modification comprising at least first and second elongated, e.g. linear, embossed patterns, said embossed The flowers, for example, intersect each other at approximately their respective midpoints. Each embossment has a cross-sectional geometry that is substantially semicircular, such as a circle, whereby upon application of a bursting force in the straw pushed onto the intersection of the embossments, the area immediately adjacent to its intersection has substantially more Areas where the flower nodes are arranged laterally outwards have less resistance to rupture.

The present invention is particularly useful for providing optional access to the contents of a container formed from a paperboard substrate having a barrier or sealing outer layer of polymeric material bonded to one or both of the outer surfaces of the paperboard. In this latter embodiment, the embossing is applied to the blank that will form the container. Preferably, the embossing projects outwardly from the outer surface of the wall of the finished container, but embossing may be performed from either outer surface of the container blank if desired.

In the method of the invention, the blank intended to be erected as a container is molded according to the invention using a male die and a female mating die, the male die being preferably arranged on the surface of the blank which will eventually become the inner wall of the erected container. By selecting the degree of closure between the male and female dies and the dimensions and geometry of the protrusions on the male die and the cavities in the female die when the laminate board is placed therein, the method of the present invention can reproducibly provide a uniform embossed and embossed with less consistent rupture than all plies of the laminate paperboard or, if desired, non-disruption of any ply of the laminate or of one or more plies of the laminate other than at least one ply, At least one of the layers is designed as a barrier to prevent gas or liquid from penetrating into or out of the container, or as a heat-sealing layer in a container formed from the blank. The resulting embossing can be easily broken using common drinking straws.

According to one aspect of the invention, a blank includes a substrate having a plurality of score lines. The base is configured to be folded along a plurality of score lines to form a sealed enclosure. A region of structural weakness is defined on a portion of the substrate. The structurally weakened area includes a plurality of embossments designed to be produced by a pair of male mold inserts acting on opposite sides of the substrate. The structurally weakened region includes a thickness substantially less than the thickness of the substrate. The structurally weakened region is configured to rupture upon application of a force thereon to allow access to the interior region of the sealed enclosure.

According to another aspect of the invention, a container includes a blank having a paperboard layer with opposing surfaces. The blank is configured to be integrally folded to form a sealed enclosure having a top wall, a bottom wall and side walls. A plurality of barrier and seal layers disposed on at least one opposing surface of the paperboard plies. A region of structural weakness is defined on a portion of the top wall. The structurally weakened area includes a plurality of embossments designed to be produced by a pair of male inserts. Each of the plurality of embossments includes a thickness substantially less than the thickness of the substrate, and the plurality of embossments further includes a geometry selected such that the plurality of barrier and sealing layers remain functionally intact when the laminate is molded . The structurally weakened area is configured to rupture upon application of a force on the structurally weakened area at the plurality of embossed locations.

According to another aspect of the invention, a blank forming apparatus produces an embossment on a portion of a blank. The apparatus includes die cylinders designed to be mounted longitudinally on the blank forming apparatus. A plurality of die inserts having a plurality of embossments are releasably mounted on the plurality of die cylinders in a longitudinal direction. A plurality of mold inserts are configured to cooperate with each other to create regions of structural weakness on portions of the blank passing therethrough.

According to another aspect of the present invention, there is provided a method for manufacturing a blank. The method includes the steps of providing a substrate having a plurality of score lines and producing an embossing pattern on the substrate by using a pair of male mold inserts The embossing pattern is defined by a plurality of shallow indentation embossments that intersect each other. The location of the intersection of the multiple shallow indentation embossments defines a structurally weakened area that has less breakup than the rest of the embossed pattern resistance.

Description of drawings

Figure 1 is an expanded view of one embodiment of a blank for forming a container having a rupturable region defined in a top wall in accordance with the present invention;

Figure 2 is a top view of one embodiment of the embossing pattern of the present invention;

3 is a cross-sectional view taken along line 3-3 of FIG. 2, of a portion of the top wall of a container and including an embossed pattern embodying aspects of the present invention and also depicting a straw suspended for rupture of the illustrated embossing;

Figure 4 is a side elevational view of a portion of the container wall shown in Figure 3 and schematically shows the straw penetrating the wall via a rupturable opening in the wall of various aspects of the present invention;

Figure 5 is a perspective view of an embossment in a container wall and embodies various features of the present invention;

Figure 6 is a view of an alternative embossing pattern embodying various features of the present invention;

Figure 7 is a view of an alternative embossing pattern embodying various features of the present invention;

Figure 8 is a view of an alternative embossing pattern embodying various features of the present invention;

Figure 9 is a view of an alternative embossing pattern embodying various features of the present invention;

Figure 10 is a view of an alternative embossing pattern embodying various features of the present invention;

Figure 11 is a view of an alternative embossing pattern embodying various features of the present invention;

Figure 12 is a side elevational view in section of a typical die used in forming embossments of the present invention;

Figure 13 is a cross-sectional view of a portion of a laminate paperboard used in the present invention;

Figure 14 is a cross-sectional view of a portion of another laminate paperboard useful in the present invention; and

Figure 15 is an illustration of one embodiment of an apparatus for molding a laminate according to the present invention.

Figure 16 is a perspective view of a second embodiment of an embossing pattern of the present invention;

Figure 17 is a side view of the embossment shown in Figure 16;

Figure 18 is a side view of a pair of male molds facing each other;

19 is a cross-sectional view of a portion of a substrate used in a second embodiment of the invention; and

Figure 20 is an illustration of a second embodiment of an apparatus for molding blanks according to the invention.

Detailed ways

The invention relates in particular to containers for containing liquid food, which are intended to be entered and sucked from the interior of the container via the usual straws which also serve to rupture a relatively small area of weakness in the wall (usually the top) of the container and thus The straw is allowed to enter the interior of the container as is well known in the art and need not be described in detail.

Figures 3 and 4 show that part 20 of the top wall 22 of the container and the end 24 of the straw 26 enter the interior of the container via a weakened area 38 in the container wall which is ruptured with the end of a straw.

In one embodiment of the present invention, a paperboard laminate 10 (FIGS. 13 and 14) includes a paperboard substrate 12 having a thickness, for example, between about 15 and about 17 mils. In a typical paperboard laminate used in a container, at least one and usually two opposing surfaces 14, 16 of the paperboard have bonded thereto a barrier layer 18, 19, typically a polymeric material such as polyethylene and It can also act as a barrier to prevent gas(es) or liquid(s) from entering or passing through the container wall and/or as a blank to form a sealant for use in the container. This barrier or sealing layer can typically be, for example, about 25 micron thick. Although the laminates shown in Figures 13 and 14 are comprised of only two and three layers, respectively, it should be understood that the laminate may comprise additional layers if desired or required for a particular application of the laminate.

Figure 1 shows a typical blank 30 used in the formation of a common gable top container, which includes an embodiment of an embossing pattern 28 defined on the top of the blank that ultimately becomes the top of the container 34 in one plate 32 . The illustrated blank includes various fold lines 36, such as typically formed as score lines in the thickness of the blank.

Referring to FIGS. 2-5 , according to one aspect of the invention, the wall 22 of the container for liquid food is provided, for example, with a structurally weakened region 38 designed to be ruptured using a common drinking straw 26 . In the present invention, the weakened area takes the form of an embossment 40 defined in the container wall and comprises at least first and second generally elongated (eg linear) portions 42 and 44 respectively, the first and second overall Upper elongated portions 42 and 44 intersect each other, for example at approximately a midpoint 46 thereof. In the illustrated and preferred embossment, each linear portion of the embossment is of substantially semicircular cross-section, as shown in FIGS. 3 , 5 , 13 and 14 . Since they are formed by embossing, each thread-like portion is weakened to a first degree and is susceptible to breakage. In the present invention, it is very important that by using such intersecting first and second generally elongated portions (linear semicircular cross-sectional portions) 42, 44 of embossing, the inventors of the present invention are on the line A region is provided in the intersection 46 of the linear portions which can be weakened to a second degree which provides less resistance to rupture than the remainder of each linear portion of the rupture embossment. Thus, the embossed pattern of the present invention provides an area in the embossed pattern that can be easily broken by the force exerted against this area using the end of a common drinking straw, thereby providing quick and easy substantially linear Initial initiation of rupture of weakened intersection points of embossing. Once the weaker intersection area begins to rupture, less force is required to extend the rupture laterally from the intersection area into the area of the line-like portion emanating from the intersection area of the embossed pattern. The resultant displacement of the ruptured portions 52, 54 of the embossing pattern after the straw has been inserted inside the container is shown in Fig. 4 .

According to one aspect of the present invention, the embossing pattern is selected to include at least first and second generally elongated portions (generally linear portions) 42, 44 which preferably bisect each other. The first and second generally elongated portions 42, 44 are preferably rotated by a 45 degree angle from the fiber orientation of the paperboard base. This orientation ensures that the breaking action acts uniformly on the fibers. However, the use of more than two linear portions is contemplated, but not required. Preferably, the linear portions are all of equal length, but it is also possible to use linear portions of different lengths, comprising eg alternating lengths. In the embodiment shown in FIG. 2, the terminal ends 56, 58 of the first generally elongated portion 42 and the terminal ends 60, 62 of the second generally elongated portion 44 are both downwardly tapered and/or rounded, The likelihood of rupture by extending the weakened region beyond the terminus of each linear portion is thereby reduced. In a typical embodiment, the centerline 64 of each linear portion of the embossment and the centerline 66 of the linear portion of the embossing pattern intersect each other and preferably bisect. In the embodiment of FIG. 2 , the endpoints of the two linear portions lie in an imaginary circle 68 concentric with the intersection point 46 of the linear portions. In any case, the diameter of the imaginary circle (Fig. 2) exceeds the diameter of the straw that will be used to rupture the weakened area, but does not exceed such a minimum diameter that liquid can easily leak from the container when the straw is inserted inside the container. In a typical container, the diameter of the imaginary circle will be between about 0.4 and about 0.6 inches. Additionally, although it is preferred that each linear portion of the embossing has the same geometry including the same width, it should be understood that combinations of linear portions having different widths may be used. Examples of different configurations of the line portions 78-88 of the embossments 70-79 are shown in Figures 5-11, respectively.

As shown in Figures 3, 5, 13 and 14, each linear portion of the embossing of the present invention has a semicircular cross section. In a typical embodiment using a paperboard laminate of 16 mil thickness, the width "W ₁ " of each linear portion is selected to be approximately 0.039 inches. Likewise, the height "H ₁ " of each linear portion is selected to be approximately 0.006 inches. In this example, the area of the weakened portion (intersection) of the embossed pattern is approximately 0.002 square inches. In this embodiment, the Apply a breaking force of approximately 20.91 N (4.7 lbf) (average) to the weakened area using a 4 mm diameter straw that easily breaks the embossment.

5, it can be seen that the intersection 46 of the plurality of first and second generally elongated portions 42, 44 of the embossed pattern creates a region 38 within and preferably around the center of the pattern, and the region 38 is A combination of the widths of the individual linear parts. The structure defines a weakened bridge 90 (see Figures 13 and 14) above the intersection, which comprises a stressed but integral paperboard laminate. The inventors of the present invention have found that this enlarged and weakened region provides less resistance to rupture than the remainder of each threaded portion of the embossing. Thus, when the end of a conventional drinking straw is pressed against such an enlarged region 38, an immediate and immediate initial rupture of the enlarged region occurs. The rupture readily propagates laterally from the enlarged region along each linear portion to create an opening sufficient to allow the end of the straw to fully enter the interior of the container to extract the contents of the container by suction applied at the opposite end of the straw .

Importantly, in the present invention, each pattern of embossing is imparted to the blank 30 before the blank is erected into a container. To this end, the inventors of the present invention have found that it is possible to form the desired embossing with a semi-circular cross-section using a male and female die set. A cross-sectional view of a suitable module 92 is shown in FIGS. 12 and 15 . In this module, the female die 94 is provided with a cavity 96 of truncated pyramidal cross-section for receiving therein a portion of a laminate paperboard blank which passes through the truncated pyramidal shape of the male die 102. The matching protrusion 100 of the cross-section is pressed into the cavity.

In one embodiment, the height h of the protrusion is approximately 60% greater than the depth of the cavity of the female mold. In addition, the width of the raised base of the male die is almost 57% larger than the width of the mouth of the cavity in the female die.

In another embodiment, the height h of the protrusion is about 22% shorter than the depth of the cavity of the female mold. Additionally, the width of the raised base of the male die is approximately 19% narrower than the width of the mouth of the cavity in the female die. These dimensional relationships provide a substantially uniform distribution of pressure to be applied to the paperboard laminate interposed between the male and female dies, thereby creating uniform displacement of the laminate paperboard and forming an embossing pattern whose parts are of uniform thickness. Additionally, these dimensional relationships create embossments with a substantially semicircular cross-section using a female die cavity with a truncated pyramidal cross-section and a male die protrusion. In a preferred embodiment, each embossment preferably does not extend in the plane of the outer surface (or inner surface as the case may be) of the laminate board over a distance greater than the approximate thickness of the laminate board. The final height of the embossed portion of the laminate paperboard is chosen to be limited by the extent to which the die is closed, a function that is readily accomplished and has been found to provide uniformity in the displacement of the paperboard laminate out of its sheet form and into the embossing. The male and female dies are included, ie easily incorporated into existing container blank forming machines and are relatively inexpensive such that their use in the present invention imposes relatively little additional cost on the manufacture of the container blanks. More importantly, the use of male and female dies provides control over the uniformity of displacement of the paperboard laminate during embossing formation, which is required for the automated manufacture of container blanks. Additionally, the use of a die defining an embossment having a semicircular cross-section has now been found to provide unexpected benefits with respect to optionally controlling the extent or extent of rupture of the outer polymeric layer(s) of the laminate paperboard. Therefore, the contents of the container having a rupturable region according to the present invention are not damaged, contaminated or the like. In addition, this preserved integrity of the outer layers of the laminate paperboard precludes, inter alia, leakage of liquid, whether from the exterior or interior of the container, from being absorbed by the exposed fibers of the paperboard itself and the potential failure of the composite of container strength. Significantly, the inventors of the present invention have discovered that by molding a cardboard laminate between a male and female die having a truncated pyramidal female cavity and a male projection of complementary geometry, it is possible to extrude a ply Press panels in such a manner that the desired substantially semicircular cross-sectional geometry of the embossing can be provided without cracking any of the outer layers of the laminate, or having one or more, but not all, of the layers of the laminate limited rupture.

According to one aspect of the present invention, with respect to the apparatus shown schematically in FIG. 15, there is provided a method for forming a rupturable region in a wall of a blank forming a container, comprising the steps of laminating a portion of paperboard 10 is arranged between the male die 102 and the female die 94, the laminate paperboard 10 has an outer layer of barrier or sealing material on at least one surface thereof, as shown in Figures 13 and 14, the male die 102 and the female die 94 have respective features of the protrusions 100 and cavities 96 for defining an embossment having a substantially semicircular cross-section; and pressing the male and female dies together to the extent that the embossing is defined , but without destroying or compromising the integrity of the outer layer of barrier material or other layers of the laminate. In the apparatus shown in FIG. Circumferentially, thus providing for embossing subsequently defined on a sheet of laminate paperboard which is continuously fed through nip rolls.

In a preferred method, the laminate material of the container wall is molded from the inside out of the container. That is, the embossments project from the outer surface of the container as opposed to embossments projecting inwardly from the container. This feature of the invention provides a cleaner rupture for the weakened intersection of the rupturable area, with an even propagation of the rupture along the individual linear portions of the embossment. However, the embossing can be formed from the outside inwards of the container if desired.

Referring to Figures 16-20, one of a pair of male mold inserts 110 is shown. Male mold insert 110 includes a plurality of embossments 112 . The plurality of embossments 112 includes four shallow crease embossments 114a, 114b, 114c, and 114d intersecting each other. Each shallow-crease embossment 114a-d has a substantially semicircular cross-section as shown in FIG. 19 .

FIG. 17 shows a side view of male mold insert 110 . It should be noted that each male mold insert 110 is designed and manufactured in such a way that they appear as two intersecting cylindrical surfaces 120 and 122 . This special design ensures that when the two male mold inserts are compressed on the blank, as shown in Figure 18, the substrate will weaken in the blank and the polymer layer(s) will remain intact during the molding process.

FIG. 19 shows a blank 30 with a structurally weakened region 38 in a second embodiment of the invention. As shown in Figure 20, when the two male mold inserts 110 come together, they compress on the blank and create two smooth hemispheres (areas of most weakness 126) in the blank. The centers of these hemispheres are considered to be the weakest areas 126 within the blank. The area of weakness 126 is created by the two male mold inserts 110 compressing on the blank and stretching the substrate beyond its maximum allowable stress in one section of the laminate. For example, the cardboard portion of the laminate has an elongation at break of approximately 2 to 3 percent, but the other layers of the laminate, such as the polyethylene layer, have an elongation at break of 65 to 70 percent, so that these layers will not damage. In this way, a rupturable layer can be engineered within the base structure.

Figure 20 shows a blank forming apparatus 128 for producing embossments on a portion of a blank. The apparatus includes a plurality of die cylinders 130 and 132 designed to be mounted longitudinally on the blank forming apparatus. A plurality of male die inserts 110 having a plurality of embossments are releasably mounted on a plurality of die cylinders 130 and 132 in a longitudinal direction. A plurality of male die inserts 110 are screwed through holes 134 and 135 , which are locating holes. A plurality of mold inserts are configured to cooperate with each other to create regions of structural weakness on portions of the blank passing therethrough.

It should be noted that the structurally weakened region 38 has a thickness substantially less than the thickness of the blank. Thus, a force of approximately 20.91 N (4.7 lbf) applied to the weakened region 38 would rupture the blank at the weakest region.

According to a second embodiment of the present invention, a method for manufacturing a blank is provided, as shown in FIG. 20 . In operation, the method includes providing a substrate having a plurality of score lines. Next, an embossed pattern is produced on the substrate by using a pair of male inserts. The embossing pattern is defined by a plurality of shallow indentation embossments intersecting each other. The location of the intersection of the plurality of shallow indentation embossments defines a structurally weakened region having less resistance to rupture than the remainder of the embossing pattern.

Although the invention has been described using specific values and terms, acceptable alternatives or modifications of the invention will occur to those skilled in the art and the invention is intended to be limited only as set forth in the claims hereinafter appended. stated.

Claims (16)

1. A container formed from a laminate having a paperboard layer and a layer of material on at least one opposing surface of the paperboard layer which acts as a barrier layer or a seal layer or both, the container With a top, the container includes: areas of structural weakness defined in relation to the walls of the vessel, said weakened region is bounded by at least first and second generally elongated embossments intersecting each other, Each of the embossments has a curved transverse cross-sectional geometry comprising the integrity of each ply of the laminate, wherein the embossments are designed to pass through pairs of embossments acting simultaneously on opposite surfaces of the laminate. Manufactured from a standard male mold insert, each of said embossments has a continuous length and is liquid impermeable over their length and defines a weakened area which, once abutted against said at least one of said at least first and The weakened area ruptures upon application of a rupturing force by the straw at the approximate point of intersection of the second generally elongated embossing on said weakened area. 2. The container of claim 1, wherein said cross-sectional geometry of each of said at least first and second generally elongated embossments has a substantially constant cross-sectional area. 3. The container of claim 2, wherein said intersection of said at least first and second generally elongated embossments defines a weakened area, said weakened area being opposite to said laminate at said point of intersection. The resistance to rupture at said intersection is substantially less than the resistance to rupture that either of said at least first and second generally elongated embossments has at a position laterally displaced from said intersection thereof. 4. The container of claim 1 wherein each of said embossments project outwardly from said container and beyond the plane of the outer surface of said laminate. 5. The container of claim 1 wherein each of said embossments protrude beyond the plane of the outer surface of said laminate a distance no greater than about the wall thickness of the container. 6. The container of claim 1, wherein said laminate comprises a layer of polyethylene on each opposing surface of said laminate; and wherein said embossing does not damage said laminate. The continuity of the polyethylene layer. 7. The container of any one of claims 1 to 6, wherein said embossments are substantially linear and wherein said at least first and second substantially elongated embossments are formed between said embossments. Structurally weakens the laminate in the area of the flowers. 8. A method for increasing liquid inclusions into a closed container formed from a paperboard laminate and having a top wall comprising the steps of An embossing pattern is provided in the top wall of the container, said pattern comprising at least first and second elongated embossments intersecting each other at least once along their respective lengths, wherein said embossings are designed to act simultaneously on said laminate Manufactured from pairs of aligned male mold inserts on opposite surfaces of the , each said embossment has a continuous length and is liquid impermeable over their length, Each of said elongated embossments has a curved substantially semicircular cross-sectional geometry, The location of the intersections of the embossments defines a structurally weakened region having less resistance to rupture than the remainder of the elongated embossments. 9. The method of claim 8, further comprising the step of placing the embossing as a protrusion from the exterior surface of the laminate defining the interior of the container. 10. The method of claim 8, wherein the embossings protrude from the outer surface of the laminate a distance no greater than the thickness of the top wall of the container. 11. A blank for forming a sealed container for containing liquids, comprising: a substrate having a plurality of score lines designed to be folded along the plurality of score lines to form a sealed enclosure; A structurally weakened area defined on a portion of the substrate, the structurally weakened area comprising a plurality of intersecting embossments designed to be produced by first and second male mold inserts on opposing surfaces of the substrate , the structurally weakened region comprises a thickness substantially less than the thickness of the substrate and wherein the structurally weakened region is configured to rupture upon initial application of a puncturing force thereon from outside the container to allow access to an interior region of the sealed enclosure. 12. The blank of claim 11, wherein the substrate further comprises an inner surface and an outer surface, a polymeric inner layer coated on the inner surface of the substrate, a polymeric inner layer coated on the outer surface of the substrate. and an outer layer, wherein the inner and outer layers are configured to resist a breaking force equal to 20.91N applied to the structurally weakened region of the plurality of embossments. 13. The blank of claim 12, wherein the substrate further comprises a polymeric inner surface layer coated on an inner surface of the substrate and wherein the substrate is configured to resist pressure applied to the structurally weakened region. A force of approximately 20.91N. 14. A container comprising: a blank having paperboard layers comprising opposing surfaces, the blank being designed to be integrally folded to form a sealed enclosure having a top wall, a bottom wall and side walls; A plurality of barrier and sealing layers disposed on at least one said opposing surface of a paperboard layer, at least one of said plurality of barrier and sealing layers having an elongation at break property exceeding the elongation at break property of said paperboard layer ; A structurally weakened area defined on a portion of the top wall, the structurally weakened area comprising a plurality of intersecting embossments designed to be produced by paired male mold inserts acting on opposing surfaces of the blank, each of the The plurality of intersecting embossments having a thickness substantially less than the thickness of the laminate, the plurality of intersecting embossments further comprising a geometry selected such that the plurality of barrier and seal layers remain functionally intact when the laminate is molded and wherein The structurally weakened region is configured to rupture upon application of a force to the structurally weakened region at the location of the plurality of intersecting embossments. 15. The container of claim 14, wherein the selected geometry comprises a plurality of embossments intersecting each other and wherein each embossment has a substantially semicircular cross-section. 16. The container of claim 15, wherein the embossments project inwardly from the laminate and into the plane of the paperboard ply.

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