Corrugated Barrier Cartonboard

Abstract

A cartonboard includes a substantially planar facing layer, a plurality of corrugated flutes, and a substantially continuous barrier layer disposed between the facing layer and flutes. The cartonboard may be used to form a carton blank and/or a carton.

Description

BACKGROUND

The packaging of powdered, granulated, and other hygroscopic products in foldable cartons presents unique challenges, particularly for large load applications, that is, where the contents are greater than 4 liters. Examples of such applications may include, for example, laundry detergent, pet food, fertilizers, pesticides, and countless others. Such cartons must not only provide an adequate moisture barrier to prevent clumping of the package contents, but also must be structurally stable enough to resist undesirable bulging and top compression when the packages are stacked on top of one another.

In such applications, it is common to use a relatively heavy weight folding board (e.g., from about 0.032 to about 0.038 mils thick), with reinforcing panels spot laminated to the cartonboard to provide the desired degree of bulge resistance and top compression resistance. A moisture barrier coating (e.g., a polymeric material) is typically applied to the reinforced cartonboard. However, the process for manufacturing such packages is usually intensive and costly. Further, the presence of the moisture barrier coating can interfere with gluing during assembly of the carton because some adhesives may not adhere properly to the polymeric material of the moisture barrier coating.

Thus, there is a need for a cartonboard that avoids the challenges associated with conventional cartonboard. There is further a need for a cartonboard that is suitable for large load and other applications. There is also a need for blanks for forming cartons for such applications, and cartons formed from such blanks.

SUMMARY

This application is directed generally to a material or structure that is suitable for use as cartonboard, and a carton blank and/or carton formed from the cartonboard. The material generally includes a printed (or printable) facing layer joined to a single-face corrugated substrate. The material also includes a barrier layer for reducing the transmission of moisture through the material. The barrier layer may be disposed on a side of the printable facing layer facing the flutes (or “medium”) within the interior of the cartonboard structure. In this manner, the material may be formed into a carton using conventional gluing techniques without the barrier layer preventing gluing of the carton. The barrier layer may comprise any suitable material, for example, a polymer film or polymeric material or coating.

In one aspect, the cartonboard may have a moisture vapor transmission rate of about 1 g/100 sq. in/day. In another aspect, the cartonboard may have a moisture vapor transmission rate of less than about 1 g/100 sq. in/day.

A carton formed according to the disclosure may generally have excellent top load compression and increased bulge resistance while maintaining a barrier to moisture transmission, thereby providing improved overall product protection while reducing carton failure and, therefore, unsellable products (“unsalables”). Accordingly, the material may be especially suitable for large load cartons (e.g., greater than 4 L), although it may be used for other carton sizes.

Various other features, aspects, and embodiments will be apparent from the following description and accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The description refers to the accompanying drawings in which like reference characters refer to like parts throughout the several views, and in which:

FIG. 1 is a schematic cross-sectional view of an exemplary cartonboard according to one aspect of the disclosure;

FIG. 2A is a perspective view of an exemplary carton that may be formed from the cartonboard of FIG. 1 according to another aspect of the disclosure, in a closed configuration with the tear strip intact;

FIG. 2B is a perspective view of a top portion of the carton of FIG. 2A, with the tear strip removed;

FIG. 2C is a perspective view of a top portion of the carton of FIG. 2B, in an open configuration; and

FIG. 2D is a schematic top plan view of one side of an exemplary blank for forming the carton of FIG. 2A according to yet another aspect of the disclosure.

DESCRIPTION

Various aspects of the invention may be illustrated by referring to the figures, in which several exemplary constructs are depicted schematically. For simplicity, like numerals may be used to describe like features. It will be understood that where a plurality of similar features are depicted, not all of such features necessarily are labeled on each figure. While various exemplary embodiments are shown and described in detail herein, it also will be understood that any of the features may be used in any combination, and that such combinations are contemplated by the invention.

FIG. 1 is a schematic cross-sectional view of an exemplary corrugated cartonboard structure 100 according to one embodiment of the disclosure. The structure 100 generally comprises a corrugated substrate 102 including a back liner (or facing layer) 104 joined to a corrugated medium (or flutes) 106. The structure 100 also includes a top liner (or facing layer) 108 and a substantially continuous barrier layer 110 (e.g., moisture barrier layer) disposed on a side of the top liner 108 facing the medium 106. The barrier layer 110 on the top liner 108 may be joined to the medium 106 and to the top liner 108 using adhesives 112, 114, or using any other suitable material. It will be noted that adhesive 114 may be omitted in some embodiments, as discussed below. Further, it will be appreciated that other embodiments may include a fewer number of layers or a greater number of layers.

Various materials may be suitable for use in forming the cartonboard 100. For example, the facing layer 108 may comprise coated recycled board (CRB), SBS, white top kraft, or any other suitable material. The facing layer 108 may have any suitable basis weight, for example, from about 40 to about 100 lb/msf (lb/1000 square feet), for example, from about 50 to about 80 lb/msf, for example, about 69 lb/msf. The facing layer 108 may have a quality suitable for printing, for example, using lithographic reproduction or other printing techniques. The facing layer 108 may have a basis weight of from about 40 to about 70 lb/msf, for example, about 56 lb/msf. However, other basis weights and ranges of basis weights may be used, depending on the strength requirements for the carton.

The barrier layer 110 may comprise any suitable material that provides the desired degree of resistance to moisture for the particular application (e.g., to prevent hardening or clumping of the powder or granular package contents), for example, a polymer or polymeric material in the form of a polymer film or a polymer coating. In one example, the barrier layer 110 may comprise a polyolefin, for example, low density polyethylene or high density polyethylene. In another example, the barrier layer 110 may comprise a polyester, for example, polyethylene terephthalate. However, countless other polymers or polymeric materials may be suitable.

The barrier layer 110 may have any suitable thickness, for example, from about 0.5 mil to about 5 mil, for example, from about 1 to about 4 mil, for example, from about 2 to about 3 mil, depending on the level of moisture barrier that needs to be achieved. However, other thicknesses and ranges of thicknesses are contemplated.

In one aspect, the cartonboard may have a moisture vapor transmission rate of from about 0.25 to about 1.5 g/100 sq. in/day (as measured using ASTM D895-79), for example, from about 0.5 to about 1 g/100 sq. in/day. In another aspect, the cartonboard may have a moisture vapor transmission rate of less than about 1 g/100 sq. in/day (as measured using ASTM D895-79), for example, less than about 0.9, less than about 0.8, less than about 0.7, less than about 0.6, or less than about 0.5 g/100 sq. in/day. However, the cartonboard may have a different moisture vapor transmission rate, depending on the needs of the particular packaging application.

If desired, the barrier layer 110 may undergo one or more surface treatments to improve adhesion between the barrier layer 110 and the medium (e.g., flutes) 106 of the corrugated substrate 102. In one particular example, the barrier layer 110 may be corona treated, for example, to a dyne level of from about 30 to about 50 dyne, for example, about 40 dyne. However, other suitable treatment levels may be used. Further, other surface treatments, for example, plasma treatment, may be suitable.

The barrier layer 110 may be joined to the medium (e.g., flutes) 106 and to the facing layer 108 in any suitable manner. In one example, the barrier layer 110 may be joined to the medium 106 using an adhesive 112, for example, a polyvinyl alcohol (PVA) adhesive (e.g., National Henkel 33-9192, Henkel North America, Düsseldorf, Germany). However, countless other adhesives may be suitable. Likewise, the medium 106 may be joined to the liner 104 in any manner, for example, using an adhesive 114. One exemplary suitable adhesive 114 may comprise starch; however, any other suitable adhesive material may be used. The particular adhesive(s) 112, 114 chosen may depend on the composition of the barrier layer 110 and/or other numerous factors. Further, it will be appreciated that adhesive 114 may be omitted in some embodiments, for example, where layer 112 is applied to layer 108 as a coating (extrusion or otherwise).

Any suitable corrugated substrate 102 may be used to form the cartonboard 100 of FIG. 1A. In one example, the facing layer or back liner 104 of the corrugated substrate 102 may comprise paper or paperboard have a basis weight of from about 40 to about 70 lb/msf, for example, about 56 lb/msf. The medium (e.g., flutes) 106 may comprise paper or paperboard having a basis weight of from about 20 to about 40 lb/msf, for example, about 33 lb/msf. However, other basis weights and ranges of basis weights may be used, depending on the strength requirements for the carton. Likewise, any suitable flute size may be used for a given application. In one example, flute size B may be used. However, the flute size may be adjusted to provide the desired degree of strength in the resulting carton, with A, B, and C flutes generally providing more strength than E, F, N, or G flutes. All or a portion of the medium 106 and/or facing layers 104, 108 may comprise recycled fiber, and in one example, the medium comprises at least 50% recycled fiber. However, other possibilities are contemplated.

The present cartonboard provides numerous advantages over known commercially available packages. For example, as will be appreciated by those of skill in the art, by positioning the barrier layer 110 as an interior layer of the structure 100 (rather than an outermost layer or surface), the barrier layer polymer does not interfere with the adhesives used in erecting and gluing the carton. Further, since many carton forming machines include heated components (e.g., rollers), positioning the barrier layer as an interior layer generally prevents any undesirable softening or melting of the barrier layer polymer on the equipment, for example, when the machine is stopped and the carton or carton blank is exposed to heat for an extended period of time. Additionally, the present cartonboard may offer a simplified carton construction as compared with traditional bag-in-box type packages or other barrier packages.

The cartonboard 100 (or numerous other cartonboards contemplated hereby) may be used to form various cartons or packages, for example, for large load packaging applications. For example, FIG. 2A schematically illustrates an exemplary carton or package 200 for containing a powdered or granular product or other article, in a closed configuration. The carton 200 includes a front panel or wall 202, a back panel or wall 204 (FIG. 2C), a pair of opposed end or side panels or walls 206, 208 (FIG. 2C), and a pair of opposed end closure assemblies 210, 212 (discussed in detail below). Panels 202, 204, 206, 208 and end closure assemblies 210, 212 generally surround or define an interior space 214 (FIG. 2C) for receiving the package contents. The carton 200 may be formed at least partially from the material of FIG. 1, such that layer 104 defines a interior side of the respective panels and layer 108 defines an exterior side of the respective panels.

As shown in FIG. 2A, the carton 200 includes an opening fetaure that may be in the form of a tear strip 216 extending substantially across the front panel 202 adjacent to end closure assembly 210. In this example, the tear strip 216 is defined partially by a pair of lines of disruption, for example, tear lines 218, 220 extending across at least a portion of panel 202 substantially between end or side panels or walls 206, 208. In this example, tear line 218 substantially lies along and/or defines the boundary between end closure assembly 210 and front panel 202, and tear line 220 is disposed within panel 202 proximate to, but spaced from, tear line 218. The tear strip 216 may include a tab 222 projecting outwardly from an edge 250 of panel 202. In other embodiments, the tab 222 and/or tear strip 216 may be omitted and/or replaced with other suitable opening and/or grasping features.

To activate the tear strip 216, the tab 222 may be grasped and the tear strip 216 may be pulled away from panel 202 by tearing along tear lines 218, 220 until the tear strip 216 is separated from the remainder of the package 200, as shown in FIG. 2B. In this condition, a lid portion or lid 224 and a closure flap 226 of the end closure assembly 210 are free to fold or hinge along a fold line or hinge 228 as shown in FIG. 2C, thereby providing access to the interior space 214, which may contain a powdered or granular product (not shown), for example, laundry detergent. In this manner, ample space is provided for the user to insert a scoop or other implement (if desired) for dispensing the product within the carton.

To reclose the carton 200, the lid 224 may be brought into its original configuration and closure flap 226 may be tucked into the interior space 214 such that at least a portion of the closure flap 226 is in an at least partially contacting relationship with the interior side of the front panel 202 (i.e., the side of the front panel 202 facing the interior space 214), as shown in FIG. 2B. In this manner, the carton 200 may be opened and closed repeatedly while substantially maintaining the barrier to moisture provided by the barrier layer 110 of the cartonboard 100 (FIG. 1).

If desired, the carton 200 may include a handle opening 286 in the end closure assembly 210 (or elsewhere) for receiving an optional handle or other feature (not shown) for grasping the carton 200. As will be appreciated by those of skill in the art, the handle or other feature may include a paper or polymer film backing on the interior side of the carton to prevent sifting (i.e., leakage) of the package contents from the carton and/or to prevent moisture from entering the carton.

FIG. 2D schematically illustrates a top plan view of one side (e.g., an exterior side) of an exemplary blank 230 for forming the carton 200 of FIG. 2A. The blank 230 generally includes a plurality of panels joined along lines of disruption, for example, fold lines, tear lines, score lines, cut-crease lines, or any other suitable lines of weakening or disruption. The blank 230 and each of the various panels generally has a first dimension, for example, a length, extending in a first direction, for example, a longitudinal direction, D1, and a second dimension, for example, a width, extending in a second direction, for example, a transverse direction, D2. It will be understood that such designations are made only for convenience and do not necessarily refer to or limit the manner in which the blank is manufactured or erected into the package.

The blank 230 may generally be formed from the material 100 of FIG. 1, such that FIG. 1 may also be representative of a cross-sectional view of a portion of the blank 230, taken, for example, along line 1-1.

As shown in FIG. 2D, the blank 230 includes a first panel (e.g., a front panel or front wall panel) 202 and a second panel (e.g., a back panel back wall panel) 204 that generally form the front and back panels or walls 202, 204 of the carton 200 (FIG. 2A) erected from the blank 230. A first top end flap (e.g., a front panel top end flap) 232 is joined to the front panel 202 along a transverse line of disruption, for example, tear line 218. Likewise, a first bottom end flap (e.g., a front panel bottom end flap) 234 is joined to the front panel 202 along a transverse line of disruption, for example, fold line 236.

The front panel 202 includes a line of disruption, for example, tear line 220, extending substantially across panel 202 between panels 206, 208 proximate to tear line 218. Tear lines 218, 220 define a tear strip 216 adjacent to the front panel top end flap 232. As stated above, the tear strip 216 may be omitted and/or replaced with any other suitable opening feature.

A second top end flap (e.g., back panel top end flap) 238 may be joined to the back panel 204 along a transverse line of disruption, for example, fold line 228. Likewise, a second bottom end flap (e.g., a back panel bottom end flap) 240 may be joined to the back panel 204 along a transverse line of disruption, for example, fold line 242. A closure flap 226 may be joined to the back panel top end flap 238 along a transverse line of disruption, for example, fold line 244.

If desired, the front panel top end flap 232 may include an exterior (or first) handle aperture 246. Likewise, the back panel top end flap 238 may include an exterior (or second) handle aperture 248. In the illustrated embodiment, the handle apertures 246, 248 are generally rectangular in shape and positioned to be in register with one another when the blank 230 is formed into the carton 200. However, differently shaped and/or configured apertures are contemplated.

The blank 230 also may include a pair of side panels (e.g., side wall panels) 206, 208 that generally form side panels or walls 206, 208 of the carton 200 (FIG. 2A). A first side panel 206 is joined to the front panel 202 along a longitudinal line of disruption, for example, fold line 250 and to the back main panel 204 along a longitudinal line of disruption, for example, fold line 252. A second side panel 208 is joined to the front panel 204 along a longitudinal line of disruption, for example, fold line 254.

A first side panel top end flap 256 is joined to the front panel 202 along a transverse line of disruption, for example, fold line 258. Likewise, a first side panel bottom end flap 260 is joined to the front panel 202 along a transverse line of disruption, for example, fold line 262.

An arcuate line of disruption, for example, a cut (or J-cut) 264 is disposed along a boundary between the first side panel 206, the first side panel top end flap 256, and the tear strip 216.

A second side panel top end flap 266 is joined to the front panel 202 along a transverse line of disruption, for example, fold line 268. Likewise, a second side panel bottom end flap 270 is joined to the front panel 202 along a transverse line of disruption, for example, fold line 272.

The blank 230 may also include an attachment flap or panel 274 joined to the panel 204 along a longitudinal line of disruption, for example, fold line 276. A pair of attachment panel end flaps 278, 280 may be joined to opposite longitudinal ends of the glue panel 274 along one or more transverse lines of disruption, for example, fold lines 282, 284.

In this example, panels 202, 204 and longitudinal fold lines 252, 254, 276 have substantially the same first dimension and panels 206, 208, 274 have approximately the same first dimension. However, other panel shapes and/or configurations are contemplated. Panels 226, 232, 238, 256, 266, 278 form end closure assembly 210. Panels 234, 240, 260, 270, 280 form end closure assembly 212.

To form the carton 200 (FIG. 2A) from the blank 230 according to one acceptable method, glue panel 274 may be brought into contact with the marginal edge of panel 208 (opposite fold line 254) by folding along fold lines 250, 252, 254, 276. The glue panel 274 may then be joined to panel 208 adhesively or otherwise to form a tubular structure including a pair of open ends and an interior space 214. In one embodiment, the glue panel 274 may be joined to the interior side of panel 208.

The top end closure assembly 210 may be closed by folding top end flaps 256, 266, 278 along fold lines 258, 268, 282 towards the interior space 214. Back panel top end flap 238 may be folded along fold line 228 and brought towards the interior space 214 until the interior side of panel 238 is in an at least partially facing, superposed relationship with the exterior side of panels 256, 266. At the same time, closure flap 226 may be folded along fold line 244 and inserted into the interior space 214 so that the exterior side of the closure flap 226 is in a facing relationship with the interior side of panel 202. Front panel top end flap 232 may then be folded along line of disruption 218 until the interior side of the front panel top end flap 232 is in a facing, substantially contacting, superposed relationship with the back panel top end flap 238. In doing so, handle apertures 246, 248 are brought into an at least partially superposed relationship with one another to form handle opening 286. Top end flaps 232, 238 may be joined to another adhesively or otherwise to collectively define the lid or lid portion 224 (FIG. 2C) of the carton 200.

If desired, a handle (not shown) (e.g., a Wilton style handle, although other handles may be used) may be affixed to one or both of panels 232, 238. The handle may extend through one or both handle apertures 246, 248. As stated above, the handle may include a paper or polymer film backing on the interior side of the carton to prevent sifting of the package contents from the carton and/or to prevent moisture from entering the carton.

Likewise, the bottom end closure assembly 212 may be closed by folding bottom end flaps 260, 270 along fold lines 262, 272 towards the interior space 214. Back panel bottom end flap 240 may be folded along fold line 242 and brought towards the interior space 214 until the interior side of panel 240 is in an at least partially facing, superposed relationship with the exterior side of panels 260, 270. Front panel bottom end flap 234 may then be folded along fold line 236 until the interior side of the front panel bottom end flap 234 is in a facing, substantially contacting, superposed relationship with the back panel top end flap 240. Bottom end flaps 234, 240 may be joined to another adhesively or otherwise to form the closed carton 200. The carton 200 may be used as described above.

Numerous variations are contemplated. The blanks and/or cartons form may include various opening features, die cut windows, handles, coupon and CD inserts, foil stamping, film lamination, and high gloss UV coatings. Portions of the carton may be crushed or compressed to allow for a more uniform construction. Countless other possibilities are contemplated.

Various aspects of the disclosure may be understood further from the following example, which is not intended to be limiting in any manner.

Example

A carton blank similar to the carton blank 230 schematically illustrated in FIG. 2D was used to form cartons similar to the carton 200 schematically illustrated in FIGS. 2A-2C, except that the cartons included a pour spout.

Carton A comprised a cartonboard structure similar to the cartonboard structure 100 schematically illustrated in FIG. 1, in which:

• • the top liner 108 was about 0.016 in. thick CRB (about 69 lb/msf), including 100% recycled fiber, clay coated on the top side;
  • the adhesive layer 114 was National Henkel 33-9192 polyvinyl alcohol adhesive;
  • the barrier layer 110 was about 0.001 in. thick polyethylene film, corona treated to a dyne level of about 40;
  • the adhesive 112 was National Henkel PVA adhesive 33-9192;
  • the medium 106 was about 33 lb/msf corrugated B-flute medium (about 0.125 in high), including at least 50% recycled fiber; and
  • the back liner 104 was about 56 lb/msf Kraft liner.

Carton B comprised a similar structure to the first carton, except that the barrier layer 110 was omitted.

Four samples of each carton were evaluated for water vapor transmission rate using ASTM D895-79. The cartons were filled with Arm & Hammer absorbing medium. The results are presented in Table 1. As will be evident, the use of the barrier layer 110 significantly reduced the transmission of moisture through the package.

	TABLE 1
	Sample	WVTR (g/100 in2/day)	WVTR (g/m2/day)
	A-1	0.701	10.87
	A-2	0.697	10.81
	A-3	0.685	10.62
	A-4	0.717	11.12
	avg	0.700	10.85
	B-1	7.02	108.9
	B-2	7.59	117.6
	B-3	7.45	115.5
	B-4	7.66	118.8
	avg	7.43	115.2

It will be understood that in each of the various blanks and trays described herein and contemplated hereby, a “fold line” can be any substantially linear, although not necessarily straight, form of weakening that facilitates folding therealong. More specifically, but not for the purpose of narrowing the scope of the present invention, a fold line may be a score line, such as lines formed with a blunt scoring knife, or the like, which creates a crushed portion in the material along the desired line of weakness, a cut that extends partially into a material along the desired line of weakness, and/or a series of cuts that extend partially into and/or completely through the material along the desired line of weakness; or any combination of these features.

For example, one type of conventional tear line is in the form of a series of cuts that extend completely through the material, with adjacent cuts being spaced apart slightly so that a nick (e.g., a small somewhat bridging-like piece of the material) is defined between the adjacent cuts for typically temporarily connecting the material across the tear line. The nicks are broken during tearing along the tear line. Such a tear line that includes nicks can also be referred to as a cut line, since the nicks typically are a relatively small percentage of the subject line, and alternatively the nicks can be omitted from such a cut line.

Furthermore, various exemplary blanks and packages are shown and described herein as having fold lines, tear lines, score lines, cut lines, kiss cut lines, and other lines as extending from a particular feature to another particular feature, for example from one particular panel to another, from one particular edge to another, or any combination thereof. However, it will be understood that such lines need not necessarily extend between such features in a precise manner. Instead, such lines may generally extend between the various features as needed to achieve the objective of such line. For instance, where a particular tear line is shown as extending from a first edge of a blank (or panel) to another edge of the blank (or panel), the tear line need not extend completely to one or both of such edges. Rather, the tear line need only extend to a location sufficiently proximate to the edge so that the removable strip, panel, or portion can be manually separated from the blank or package without causing undesirable damage thereto.

Although certain embodiments have been described with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of the invention. All directional references (e.g., upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are used only for identification purposes to aid the reader's understanding of the various embodiments of the invention, and do not create limitations, particularly as to the position, orientation, or use of the invention unless specifically set forth in the claims. Joinder references (e.g., joined, attached, coupled, connected, and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily imply that two elements are connected directly and in fixed relation to each other.

It will be readily understood by those persons skilled in the art that, in view of the above disclosure, the present invention is susceptible of broad utility and application. Although specific embodiments or aspects are disclosed, it will be understood that this disclosure is only illustrative and exemplary of the invention and is made merely for purposes of providing a full and enabling disclosure of the invention and to set forth the best mode of practicing the invention known to the inventors at the time the invention was made.

Many adaptations, variations, modifications, and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the above detailed description thereof without departing from the substance or scope of the present invention. It will be recognized that various elements discussed with reference to the various embodiments may be interchanged to create entirely new embodiments coming within the scope of the invention. Accordingly, all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and is not intended nor is to be construed to limit or otherwise to exclude any such other embodiments, adaptations, variations, modifications, and equivalent arrangements of the present invention.

Claims

1. A cartonboard comprising: a substantially planar facing layer;a plurality of corrugated flutes; anda substantially continuous barrier layer disposed between the facing layer and flutes, wherein the barrier layer comprises a polymeric material.

2. The cartonboard of claim 1, wherein the substantially planar facing layer is a first substantially planar facing layer, andthe cartonboard comprises a second substantially planar facing layer on a side of the corrugated flutes opposite the first substantially planar facing layer.

3. The cartonboard of claim 1, wherein the polymeric material comprises at least one of a polymer film and a polymer coating.

4. The cartonboard of claim 1, wherein the polymeric material comprises at least one of a polyester and a polyolefin.

5. The cartonboard of claim 1, wherein the polymeric material comprises at least one of polyethylene terephthalate, low density polyethylene, and high density polyethylene.

6. The cartonboard of claim 1, wherein the barrier layer has a thickness of from about 0.5 mil to about 5 mil.

7. The cartonboard of claim 1, wherein the barrier layer is joined the substantially planar facing layer with an adhesive material.

8. The cartonboard of claim 7, wherein the adhesive material comprises polyvinyl alcohol.

9. The cartonboard of claim 1, wherein the barrier layer is joined the plurality of flutes with an adhesive material.

10. The cartonboard of claim 9, wherein the adhesive material comprises a starch-based material.

11. The cartonboard of claim 1, wherein the barrier layer is corona treated.

12. The cartonboard of claim 1, wherein the cartonboard has a moisture vapor transmission rate of less than about 1 g/100 sq. in/day.

13. A blank for forming a carton, the blank comprising: a plurality of adjoined panels, the plurality of adjoined panels each having a first dimension extending in a first direction and a second dimension extending in a second direction substantially perpendicular to the first direction, the plurality of adjoined panels including a first panel, a second panel, and a third panel, the third panel being disposed between the first panel and the second panel, the first panel, second panel, and third panel being joined to one another along respective first and second fold lines extending in the first direction,a first top end flap joined to the first panel along a first tear line extending in the second direction,a second top end flap joined to the second panel along a first fold line extending in the second direction, anda closure flap joined to the second top end flap along a second fold line extending in the second direction; anda second tear line extending in the second direction substantially across the first panel proximate to the first tear line.

14. The blank of claim 13, further comprising a fourth panel joined to the first panel along a third fold line extending in the first direction.

15. The blank of claim 13, further comprising a first bottom end flap joined to the first panel along a third fold line extending in the second direction, anda second bottom end flap joined to the second panel along a fourth fold line extending in the second direction.

16. The blank of claim 13, formed at least partially from cartonboard comprising a substantially planar facing layer,a plurality of corrugated flutes, anda substantially continuous barrier layer disposed between the facing layer and flutes.

17. The blank of claim 16, wherein the substantially planar facing layer is a first substantially planar facing layer, andthe cartonboard comprises a second substantially planar facing layer on a side of the corrugated flutes opposite the first substantially planar facing layer.

18. The blank of claim 16, wherein the barrier layer comprises at least one of a polymer film and a polymer coating.

19. The blank of claim 16, wherein the barrier layer comprises at least one of a polyester and a polyolefin.

20. The blank of claim 16, wherein the barrier layer comprises at least one of polyethylene terephthalate, low density polyethylene, and high density polyethylene.

21. A carton, comprising: a plurality of adjoined panels that surround an interior space, the plurality of adjoined panels including a first panel and a second panel opposite one another, andan end closure assembly foldably joined to the first panel and the second panel, the end closure assembly including a first top end flap joined to the first panel along a first tear line,a second top end flap joined to the second panel along a fold line, the first top end flap and the second top end flap being at least partially superposed with one another, anda closure flap foldably joined to the second top end flap, the closure extending into the interior space; anda second tear line extending substantially across the first panel, the second tear line being proximate to the first tear line, the first tear line and the second tear line defining a tear strip.

22. The carton of claim 21, wherein at least a portion of the closure flap is in an at least partially contacting relationship with a side of the front panel facing the interior space.

23. The carton of claim 21, wherein the tear strip comprises a tab extending outwardly from an edge of the first panel.

24. The carton of claim 21, wherein the tear strip is for being removed, so that end closure assembly is operative for hinging along the fold line.

25. The carton of claim 21, formed at least partially from cartonboard comprising a substantially planar facing layer,a plurality of corrugated flutes, anda substantially continuous barrier layer disposed between the facing layer and flutes.

26. The carton of claim 25, wherein the substantially planar facing layer is a first substantially planar facing layer, andthe cartonboard comprises a second substantially planar facing layer on a side of the corrugated flutes opposite the first substantially planar facing layer.

27. The carton of claim 26, wherein the second substantially planar facing layer comprises a side of the cartonboard facing the interior space.

28. The carton of claim 25, wherein the barrier layer comprises at least one of a polymer film and a polymer coating.

29. The carton of claim 25, wherein the barrier layer comprises at least one of a polyester and a polyolefin.

30. The carton of claim 25, wherein the barrier layer comprises at least one of polyethylene terephthalate, low density polyethylene, and high density polyethylene.