FIELD

[0001] The present invention relates to boxes and blanks for forming boxes.

BACKGROUND

[0002] Cardboard or paperboard boxes are useful for shipping and storing materials. It is common to form such a box from a single blank. Typically, the blank has four main panels for forming the top, bottom, front and back of the box, and has side panels extending from the main panels for forming the sides of the box. In some situations, the known blanks and boxes formed by simply folding them are not adequate for storing or transporting liquids, resins, powders, bulk food products, pastes, or other similar bulk materials or products. Such bulk materials or products may need to be transported in a carton, and their quantities are typically measured by weight or volume, e.g., by the number of filled cartons. For example, when the boxes are stacked during storage or transportation, the boxes may not have sufficient resistance to vertical compression applied to the boxes and may deform and collapse under pressure. Further, when materials such as mud, powder, gypsum, or cement, are stored in the box, the liquid content can leak out through the gaps between the folded main panels and side panels. These gaps may need to be sealed with a separate sealing material, such as a tape applied to the edges of the box, or by a bag, to contain the materials.

SUMMARY

[0003] In an aspect of the present application, there is provided a blank for forming a box. [0004] In an embodiment, the blank comprises a bottom panel for forming a box bottom having four sides; a side panel foldably attached to each one of the four sides for forming a side wall extending from the each side of the box bottom; a flap foldably attached to a terminal end of the side panel for forming a portion of a box top; and support panels foldably attached to a first pair of opposite ones of the side panels, each one of the support panels being foldable onto itself along a fold line thereon to form a side support member; wherein the panels are sized and attachments of the side panels at the four sides are offset such that two of the side support panels are foldable to form side support members overlapping inside each side wall formed by one of a second pair of the side walls, and each one of the side support members abuts the box top and the box bottom when the box is formed.

[0005] The fold line may comprise a double score line to allow each support panel to be folded about 180 degrees along the fold line. Each support member may extend across the box bottom and may be folded at a corner formed by two side walls. Each pair of overlapping support members may form a three-layer support inside the respective side wall. Each support member may comprise a full-width support layer and a partial-width support layer. The partial-width support layer may be a half-width support layer. The support panels may be sized and configured such that each pair of overlapping support members are foldable to offset their partial-width support layers and sandwich their partial-width support layers between their full-width support layers. The separation between adjacent panels may be provided by slit cut. The two sides of the box bottom attached to the second pair of side panels may be defined by straight parallel fold lines. Each side of the box bottom attached to one of the first pair of side panels may have a middle portion defined by a straight fold line and two end portions defined by inclined cuts such that the box bottom is inwardly recessed at the middle portion. The inclined cuts at a first side may comprise a tapered section and a stepped section, each of the tapered section and stepped section may have a cut length of about a thickness of the blank. The inclined cuts at a second side may comprise straight, tapered cuts each having a cut length of about three times of the blank thickness. The blank may have a substantially uniform thickness. The blank may be formed of a corrugated cardboard having a flute direction substantially parallel to the fold lines on the support panels. The support panels may be sized such that when the box is formed, the side support members sealingly abut the box top and the box bottom. The support panels may be sized such that when the box is formed, each pair of the side support members comprise an inner support member and an outer support member, and each terminal edge of the inner support member sealing abuts an internal surface on the box top, the box bottom, or one of the side walls.

[0006] In another aspect, there is provided a box formed from a blank as described herein. In the box, the overlapping support members and the respective side wall at each side may be attached to one another by an adhesive.

[0007] Other aspects and features of the present invention will become apparent to those of ordinary skill in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In the figures, which illustrate, by way of example only, embodiments of the present invention,

[0009] FIG. 1 is a plan view of a blank for a box, exemplary of an embodiment of the present invention;

[0010] FIG. 1 A is an enlarged view of the portion marked as 1A in the blank of

FIG. 1 ;

[0011] FIG. 2 is a perspective view of the blank of FIG. 1 ;

[0012] FIGS. 3, 4, 5, and 6 are perspective views of the blank of FIG. 1 , at different stages of being folded to form a box; [0013] FIG. 7 is a perspective view of a box formed from the blank of FIG. 1 , exemplary of an embodiment; and

[0014] FIG. 8 is a plan view of a blank for a box, exemplary of an embodiment of the present invention.

DETAILED DESCRIPTION

[0015] FIG. 1 depicts a box blank 100, exemplary of an embodiment of the present invention. It should be understood that, unless expressly indicated otherwise, the solid lines in the drawings indicate edges that are not directly attached to one another, and the thin dashed-lines indicate fold lines, which may be formed of score lines. The thick dash-dotted line in FIG. 1 does not indicate any physical feature or boundary but is used to indicate a region 1A, an enlarged view of which is shown in FIG. 1A.

[0016] Blank 100 has a plurality of panels including a bottom panel 110, and a first pair of opposite panels 120, 130 and a second pair of opposite panels 140, 150. Bottom panel 110 has four edges 112, 113, 114, 115. Each side panel 120, 130, 140, 150 is attached to a respective edge 112, 113, 114, 115 of bottom panel 110.

[0017] As depicted, each one of panels 120, 130, 140, 150 has a lower edge

121 , 131 , 141 , 151 attached to a respective edge of bottom panel 110, and an upper edge 122, 132, 142, 152. Each one of panels 120, 130, 140, 150 also has side edges 123, 124; 133, 134; 143, 144; 153, 154. Fold lines are provided at the edges between bottom panel 110 and respective panels 120, 130, 140, 150.

[0018] Panels 160, 170 are attached to opposite side edges 123, 124 of panel

120 respectively. Panels 180, 190 are attached to opposite side edges 133, 134 of panel 130 respectively. Each panel 160, 170, 180, 190 has a lower edge 161 , 171 , 181 , 191 , an upper edge 162, 172, 182, 192, and side edges 163, 164; 173, 174; 183, 184; 193, 194 respectively. [0019] Panels 140, 150, 160, 170, 180, 190 are separated from one another at the respective adjacent edges by slit cuts, such that panels 120, 130, 140, 150 folded upwards at their respective lower edges 161 , 171 , 181 , 191 , and each panel 160, 170, 180, 190 can be folded at the respective side edge 163, 173, 183, 193 attached to the respective panel 120, 130.

[0020] As depicted, each panel 140, 150 may optionally have a pre-cut slot portion 145, 155. Each slot portion 145, 155 is only partially connected and can be conveniently detached to form a slot suitable for receiving a human hand for handling the box to be formed, as will be further described below.

[0021] A half-length panel 146, 156 may be attached to panel 140, 150 at its upper edge 142, 152. A fold line is provided at the upper edge 142, 152 to allow panel 146, 156 to be folded at the respective upper edge 142, 152. The two half-length panels 146, 156 are sized to form a full-length top of the box to be formed. In a different embodiment, instead of providing two half-length top panels, a full-length top panel may be attached to one of side panels 140, 150. The half-length panels 146, 156 may be sized such that in the box to be formed, panels 146, 156 would not overlap but the terminal edges 147, 157 of panels 146, 156 would be close to, or even abut, each other to fully cover the top of the box.

[0022] For convenience of description, it is assumed that bottom panel 110 and side panels 120 and 130 are serially connected in a direction referred to as the widthwise or transversal direction, and bottom panel 110 and panels 140 and 150 are serially connected in a direction referred to as the lengthwise or longitudinal direction. Accordingly, the dimension of the blank, and of the formed box, in the widthwise direction is referred to as the width; and the dimension of the blank, and of the formed box, in the lengthwise direction is referred to as the length. As depicted in the figures, the length of blank 100 is larger than its width. However, it should be understood that the terms "lengthwise", "length", "longitudinal", "widthwise", "width", and "transversal" are used herein for ease of reference, and it is not necessary that the length of blank 100, or any component thereon, is longer than the corresponding width. In some embodiments, a length may be equal to or shorter than a corresponding width of the same blank or a given portion of the blank. Further, references to the length or width of a component portion of the blank or box may change depending on how the

component portion is relatively positioned with respect to the bottom panel. For example, a portion of the blank may be folded so that its length in the blank becomes its width in the folded box or becomes its height. It should also be understood that the terms "full-length," "full-width,", "half-width," and "half-length" refer to the length and width of the formed box or its sides, not the blank itself.

[0023] Each panel 160, 170, 180, 190 has a fold line 165, 175, 185, 195 extending parallel to its side edges and positioned at less than 1/3 or one-half of the length of the panel from its terminal edge 164, 174, 184, 194, to provide a foldable portion 166, 176, 186, 196. As such, and as will be further described below, each panel 160, 170, 180, 190 can provide a full-width support layer and a partial-width (e.g. half-width) support layer. Fold lines 165, 175, 185, 195 may be provided by double score lines to allow the panel to be conveniently folded 180 degrees at the double score line. In a particular embodiment, the double score lines may be separated by a distance of about 8 mm. However, in different embodiments the distance between the double score lines may change, and may be selected depending on the specific material used for the particular application, to provide the needed flexibility to fold the panel 180 degrees without significant separation between the folded portions.

[0024] As depicted, each panel 160, 170, 180, 190 may optionally have a cut out slot 168, 178, 188, 198, which is sized and positioned to correspond with

respective slot portions 145, 155. A correspondingly shaped and sized notch 169, 179, 189, 199 may be provided at each terminal edge 164, 174, 184, 194.

[0025] Slot portions 145, 155, slots 168, 178, 188, 198 and notches 169, 179,

189, 199 are positioned and sized to provide hand slots in the formed box for easy handling of the box, as will be further described below.

[0026] A flap 125, 135 is attached at upper edge 122, 132 of each panel 120,

130, and is foldable to provide support for the top of the box to be formed. [0027] Panels 110, 120, 130, 140, 146, 150, 156 are sized and shaped so that when they are folded they can form the respective external sides of a box having the desired shape and size, which will be selected based on the particular application.

[0028] Panels 160, 170, 180, 190 and portions 166, 176, 186, 196 are shaped and sized to form multi-layer internal side support and to provide self-sealing in the box, as will be further described below.

[0029] The cuts at or near different corners of bottom panel 110 are different and are specifically arranged to provide the desired configuration of the side panels and supports. The cuts in the depicted embodiment are better illustrated in FIG. 1A. To make it clear where each slit cut extends, the opposite edges of the panels separated by slit cuts are indicated by two solid lines separated by a gap in FIG. 1A. However, it should be understood that, in reality, it is not necessary the two opposite edges are separated by a gap. In many cases, the two separate edges may still contact each other and there is no gap in between before the panels are folded.

[0030] As depicted, edges 114, 115 are defined by straight parallel fold lines, and each of edges 112, 113 has a middle portion defined by a straight fold line and two end portions defined by inclined cuts such that bottom panel 110 is inwardly recessed at the middle portion.

[0031] The inclined cuts defining the end portions of edge 112 may comprise straight, tapered cuts, each of which has a cut length of about three times of the blank thickness. The inclined cuts defining the end portions of edge 113 may include a tapered section and a stepped section, as can be seen in the depicted embodiment. Each of the tapered section and stepped section may have a cut length of about the blank thickness.

[0032] As can be appreciated from the depicted embodiment shown in FIG. 1 and 1A, the lower edge 131 of side panel 130 is defined by the two tapered sections and the middle portion of edge 113. The length of side panel 130 is thus the length of bottom panel 110 minus the total length of the two stepped sections at the ends of edge 113. The lower edge 121 of side panel 120 is defined by the middle portion of edge 112, and the length of side panel 120 is thus the length of bottom panel 110 minus the total length of the two tapered cuts at the ends of edge 112.

[0033] Thus, the slit cuts at the corners of edges 112, 113, 114, 115 of bottom panel 110 are formed such that bottom panel 110 is longer than each of panels 120, 130, and panel 130 is longer than panel 120. As the length of the blank is generally uniform, panels 160, 170 are consequently longer than panels 180, 190. Further, due to the shapes of the cuts, panels 120, 130 are taller (wider) than panels 160, 170, 180, 190.

[0034] As can be better seen in FIG. 1A, panel 110 is not strictly rectangular shaped. Rather, panel 110 has a recessed middle portion between edges 112 and 113. That is, panel has a larger (max) width at, and near, edges 114 and 115 and a smaller (min) width away from edges 114 and 115.

[0035] Correspondingly, due to the slit cuts at the corners of bottom panel 110, panel 120 has a rectangular shape with a straight lower edge 121 extending to the full length of panel 120, but panel 130 is not strictly rectangular shaped, as panel 130 has tapered corners at its lower edge 131 , and the portion of lower edge 131 that is connected to bottom panel 110 does not extend to the full length of panel 130. Panel 130 thus has a taller (wider) middle portion away from its side edges 133, 134, and shorter (narrower) side portions at side edges 133, 134. Panels 120, 130 are, however, of the same maximum height (width).

[0036] The lower edges 161 , 171 of panels 160, 170 are tapered near side edges 163, 173 such that panels 160, 170 are taller (wider) at side edges 163, 173. In comparison, lower edges 161 , 171 of panels 180, 190 are straight and do not taper at side edges 163, 173. With the exception of the tapered ends at side edges 163, 173, panels 160, 170, 180, 190 are of the same height (width).

[0037] As will become clear below, the slit cuts and the above noted

differences between corresponding panels in shape, height (width) and length allow panels 160, 170, 180, 190 to be folded inside the box, and to extend the full-height, so as to provide internal support and self-sealing.

[0038] In blank 100, any fold line may be provided by a score line.

[0039] As shown, blank 100 is generally rectangular, and only a small portion of the original blank material needs to be cut off from the original blank material.

However, in different embodiments, the blanks may have other general shapes suitable for the particular applications.

[0040] In a specific embodiment, blank 100 may have the dimensions as shown in Table I.

Example Blank Dimensions

(blank thickness: 3 mm)

[0041] During use, the panels and flaps may be folded as illustrated in FIGS. 2-

6 to form the box shown in FIG. 7.

[0042] As shown in FIG. 2, portions 166, 176 of panels 160, 170 are folded 180 degrees along fold lines 165, 175 towards outside of panels 160, 170, and portions 186, 196 of panels 180, 190 are folded 180 degrees along fold lines 185, 195 towards inside of panels 180, 190. Optionally, an adhesive such as glue may be applied to the outside of panels 160, 170 and the inside of panels 180, 190 to glue the respect folded portions 166, 176, 186, 196 thereon.

[0043] As shown in FIG. 3, panels 120, 160, 170 may be folded along the fold lines at the respective connected edges to form walls at 90 degrees with respect to one another and bottom panel 110.

[0044] As shown in FIG. 4, panels 130, 180, 190 may be folded along the fold lines at the respective connected edges to form walls at 90 degrees with respect to one another and bottom panel 110. Panels 180, 190 are folded onto the outside of panels 160, 170 respectively. Optionally, an adhesive such as glue may be applied to surfaces of the panels that will be in contact with one another to glue the panels in contact together.

[0045] As shown in FIG. 5, top flaps 125 and 135 may be folded at 90 degrees along upper edges 122 and 133 of panels 120 and 130.

[0046] An adhesive may be applied to the top surface of top flaps 125 and 135, and may be applied to outside of panels 180, 190.

[0047] As shown in FIG. 6, panels 140, 150 are folded 90 degrees to outside of panels 180, 190 at lower edges 141 , 151 , and top panels 146 and 156 are folded at 90 degrees along upper edges 142 and 152. It can be seen that support panels 160, 170, 180, 190 extend across and overlap inside respective box sides formed by panels 140, 150.

[0048] The folded box 200 is shown FIG. 7. As can be seen, the slot portions, slots and notches in the panels are sized and positioned so that they co-register in the formed box. The slot portions 145, 155 may be removed, or folded up, to provide a handling slot 202 on each of the opposite sides formed by panels 140, 160, 180 and panels 150, 170, 190 respectively. [0049] As now can be appreciated, due to the particular cut and configuration of the panels, panels 160, 170, 180, 190 provide a three-layer side support inside each side panel 140, 150 of box 200. Specifically, as can be seen in FIGS. 5 and 6, each three-layer support includes an inner full-width layer formed of panel 160 or 170, a middle layer formed of half-width portions 166 and 186 or 176 and 196, and an outer full-width layer formed of panel 180 or 190. The off-sets provided by the different widths and lengths of the panels allow the different layers to fold without difficulties or bulging. Further, the off-sets are provided such that each of the three-layer supports abuts the inside surfaces of the top and bottom of the box, and can provide self- sealing at the lower and upper edges. Conveniently, when the box is vertically compressed, the pressure applied to the sides of the box further improves the sealing effect.

[0050] Fold lines 165, 175, 185, 195 on panels 160, 170, 180, 190 may be positioned such that the folded support panel can abut the folded opposite side panel 120 or 130 as illustrated in FIG. 5, so as to provide sealing at the side edges of box 200.

[0051] Conveniently, box 200 can withstand increased vertical compression, as compared to some conventional boxes formed of a single blank, and can, at the same time, provide self-sealing. Thus, the boxes may be filled with liquid contents such as mud, gypsum, or cement, or powder; and may be stacked during storage or transportation with a reduced chance of collapsing the boxes or causing leakage of the liquid contents. The quantity of the materials or products contained in the box may be measured by volume or weight. For example, certain liters of the material per box or certain kilograms of the material per box.

[0052] Blank 100 may have a substantially uniform thickness, which in some embodiments may be from about 3 mm to about 13 mm.

[0053] To provide the required configuration and off-sets, in an embodiment, each of edges 133, 134 is off-set from the nearest one of edges 114, 115 by at least the thickness of blank 100; each of edges 123, 124 is off-set from the nearest one of edges 114, 115 by about three times of the thickness of blank 100.

[0054] Blank 100 may be formed of a corrugated cardboard having a flute direction substantially parallel to edges 114, 115 of bottom panel 110, such that in the formed box the flute direction is vertically oriented.

[0055] In an alternative embodiment, a blank may have a configuration as shown in FIG. 8.

[0056] As is typical for blanks used to form packaging boxes, the panels may have generally rectangular shapes so that the resulting box may have a substantially rectangular or cubic shape. Boxes with a substantially rectangular or cubic shape may be convenient to handle and store in many situations.

[0057] In cases where a blank has a varying thickness, the skilled person should be able to adjust the off-sets in view of the present disclosure so that the resulting folded box will have the same or similar support and sealing properties as described here.

[0058] As used herein, a slit cut is a cut where little material is removed by the cut and the adjacent panels after the slit cut may still be in contact with one another, or there may be only a narrow gap between the adjacent panels after the slit cut. With such slit cuts, the adjacent panels are severed from one another but may still abut each other.

[0059] Blank 100 may be formed of any suitable material for box blanks and packaging boxes. For example, corrugated boards, cardboard, paper board, fibreboard, or plastics may be used. Suitable material may include double faced corrugated cardboard. Other materials typically used for forming shipping or packaging boxes may be used. Known box materials that are particularly suitable for containing the specific liquid contents for which the boxes will be used, may be conveniently selected. For example, the blank material may have a suitable top-to- bottom compression strength, which may be measured by an Edge Crush Test (ECT). In selected embodiments, the blank may have 23, 26, 29, 32, 40, 44, 42, 48, or 51 ECT. The blank formed of corrugated boards may have a flute size of E, F, B. C, A, or N, depending on the strength required. Liners and mediums may also be selected and used to help to achieve the desired stacking strength. Various options for the above parameters may be considered and selected to achieve the overall strength desired in a particular application.

[0060] Glues or other adhesive materials or suitable configurations for attaching or fixing different parts of blank 100 may be optionally provided at the appropriate locations on blank 100, if desired. In particular, glues or other adhesive materials may be applied to some or all of the surfaces of the panels or flaps which will come into contact with one another when the box is formed.

[0061] Blank 100 may have any suitable thickness and size. As noted earlier,

Blank 100 may have a substantially uniform thickness. In some embodiments, blank 100 may have a thickness from about 1 mm to about 13 mm. In a particular

embodiment, blank 100 may have a thickness of about 3 or about 4 mm.

[0062] Blank 100 may be manually folded into a box 200 in selected

embodiments. In other embodiments, a box packing machine may be used to fold blank 100 and package box 200.

[0063] A vertical compression may be applied to the box during assembly, packaging, shipping, storage, or unpacking. For example, when a machine is used to form and package the box, a vertical compression may need to be applied by the machine during the packaging process. When boxes are stacked for storage or transportation, a vertical compression may also be applied on the lower boxes.

[0064] Conveniently, folded panels 160, 170, 180, and 190 provide improved vertical support and resistance against deformation under vertical compression, as compared to conventional boxes without such internal supports. [0065] As can be appreciated, when a corrugated board is used to form blank

100 and hence box 200, and the flute direction in side walls of box 200 is substantially in the vertical direction, it can conveniently provide increased vertical strength, as compared to other orientations of the flute direction.

[0066] Conveniently, three-layer supports can provide improved resistance against vertical compression, as compared to a single- or double-layer supports that are formed of the same blank material with the same thickness.

[0067] Conveniently, the three-layer support as disclosed herein can be formed with a single blank and without forming undesirable protrusions inside the box. In particular, the internal side surfaces of the box can be conveniently all flat. Thus, the internal space in box 200 can have a substantially regular shape, so that it may be convenient to package goods or products that have regular individual shapes. Of course, the box may also be used to package goods or products that are of an irregular shape, or do not have a defined shape.

[0068] When two overlapping portions in the box are to be attached, the overlapping portions may be glued, or may be stapled, taped, or otherwise attached or affixed together.

[0069] In an exemplary embodiment, blank 100 may be formed using various different types of known methods and systems for forming such blanks, appropriately adapted to form the features disclosed herein.

[0070] For example, the making of a blank from a corrugated fibreboard material can start with first forming a sheet of corrugated material using a corrugator machine, such as one provided by BHS Corrugated, Maschinen-und Anlagenbau GmbH™. The corrugator machine may produce a length of corrugated material of a given width that can be used immediately or stored in a roll until it is ready to be utilized. [0071] The next step may involve utilizing a roll or sheet of such corrugated material that may have an approximate width that may be the same as the width of the desired blank that may be used to form the box. The roll or sheet can be also cut transversely such as to create sections of cardboard that are generally rectangular in shape. The corrugated material may then be fed through what is known as a flexo- folder gluer machine, rotary die cutter, or flatbed die cutter. In passing through such a machine, the corrugated sheet may pass through a printer, which prints words or pictures on one or both sides of the sheet. Next, the material may be creased both across and along the sheet material such that when the blank is folded/erected it may easily bend along the crease (fold) lines to form the desired shape.

[0072] The creased sheet may then be slit with a cut device which cuts thin slits in the board at designed intervals along desired directions. These slits create panels and flaps that may be folded.

[0073] A flat blank may thus be formed. Certain portions of the blank may be pre-folded and glued using a suitable folding mechanism or folding machine.

[0074] The box may be filled with the desired content by any known technique.

[0075] As can be understood, blank 100 may be modified without losing all of its benefits.

[0076] For example, the slots 202 for handling may be omitted, particularly if it is desirable to avoid any possible leakage. A tear line may be provided on the blank for purposes known to those skilled in the art.

[0077] Conveniently, as illustrated above, a storage and shipping container may be formed from a single blank according to exemplary embodiments disclosed herein. Thus, the manufacture and assembly process may be simplified as compared to boxes that are formed from multiple pieces of blanks. However, in different embodiments, additional components or attachments may be added to the blanks or assembled boxes, if desired. [0078] As can be understood, the panels in the blank are typically substantially rectangular, except as specifically described herein, as depicted in the drawings.

However, in different embodiments, one or more of the panels may have a different shape. For example, one or more panels may have a curved terminal edge.

[0079] One or more permanent openings may also be provided in one or more of the panels and flaps of the blanks for various purposes depending on the

application.

[0080] To describe blank 100 in alternative languages, it may be said that blank

100 comprises a bottom panel 110 for forming a box bottom having four sides 112, 113, 114, 115. A side panel 120, 130, 140, 150 is foldably attached to each side for forming a side wall extending from each side of the box bottom. A flap 125, 135, 146, 156 is foldably attached to a terminal end 122, 132, 142, 152 of the side panel 120, 130, 140, 150 for forming a portion of a box top. Support panels 160, 170, 180, 190 are foldably attached to a first pair of opposite side panels 120, 130. Each support panel 160, 170, 180, 190 is foldable onto itself along a fold line 165, 175, 185, 195 thereon to form a side support member. The panels are sized and attachments of the side panels at the four sides are offset such that two of the side support panels are foldable to form side support members overlapping inside each side wall formed by one of a second pair of side walls 140, 150, and each side support member abuts both the box top and the box bottom when the box is formed. Each support member may extend across the box bottom and may be folded at a corner formed by two side walls. Each pair of overlapping support members may form a three-layer support inside the respective side wall. Each support member may comprise a full-width support layer and a partial-width support layer. The support panels may be sized and configured such that each pair of overlapping support members are foldable to offset their partial- width support layers and sandwich their partial-width support layers between their full- width support layers. Sides 114, 115 of the box bottom are defined by straight parallel fold lines. Each side 112, 113 has a middle portion defined by a straight fold line and two end portions defined by inclined cuts such that the box bottom is inwardly recessed at the middle portion. The inclined cuts at side 113 comprise a tapered section and a stepped section, each of the tapered section and stepped section may have a cut length of about a thickness of the blank. The inclined cuts at side 112 comprise straight, tapered cuts each having a cut length of about three times of the blank thickness. The blank may be formed of a corrugated cardboard having a flute direction substantially parallel to fold lines 165, 175, 185, 195. The support panels may be sized such that when the box is formed, the side support members sealingly abut the box top and box bottom. The support panels may be sized such that when the box is formed, each pair of the side support members comprise an inner support member (e.g. support members formed by panels 160, 170 as seen in FIG. 4) and an outer support member (e.g. support members formed by panels 180, 190 as seen in FIG. 4), and each terminal edge of the inner support member sealing abuts an internal surface on the box top, box bottom, or a side wall (e.g. side wall 130 as seen in FIG. 5). In a box formed from blank 100, the overlapping support members and the respective side wall at each side may be attached to one another by an adhesive.

[0081] Examples

[0082] Sample blanks having the configuration of blank 100' as shown in Fig. 8 were made and tested for compression resistance. Blank 100' was similar to blank 100 in construction and configuration except that the dimensions of the various panels arid portions were different as can be seen from Fig. 8 and as listed in Table II. The internal dimensions of the sample boxes formed from the sample blanks were roughly 280 mm x 280 mm x 229 mm. The sample blanks were made of corrugated paper boards with ECT 32 (referred to as Example A) or ECT 40 (referred to as Example B). The sample blanks were formed by rotary die cutting (RDC). The overlapping layers in the side support walls were glued together using adhesives such as hot melt glue. Table II. Dimensions of Tested Sample Blanks

(blank thickness: 3 mm)

[0083] Compression tests were conducted for boxes formed from the sample blanks as described herein, and for a comparison box (referred to as Comparison Box).

[0084] The Comparison Box was a Single-Wall Standard Flat (SWSF) box formed of ECT 51 corrugated board material by Platen Die Cutting (PDC). The

Comparison Box had internal dimensions of about 255 mm x 255 mm x 229 mm. The overlapping panels were also glued inside.

[0085] The tested boxes were all rated to hold 23 kg weight. The tests were conducted at room temperature (23 °C) with 50% relative humidity (RH). Further properties of the components of the test boxes and representative test results are listed in Table III. In Table III, the weights indicated are average weights; "MRA" refers to Moisture Resistant Adhesive; and "WT" refers to White Top. The take-up factors for medium wt. calculation is B = 1.31 and C = 1 .40. Table III. Properties and Test Results of Tested Box Materials

[0086] The test results indicated that the compression strength of the Examples

I, II and III was improved over the Comparison Box, even though the Comparison Box had a smaller dimension and was made of a stronger blank material. For example, as compared to the Comparison Box, the example boxes formed from the sample blanks had markedly increased peak strength, e.g., by about 35% with Example I, and by about 70% with Example II. Each side wall formed of glued multiple-support layers in Examples I, II, and III provided the equivalent strength of five (5) times of a single-wall corrugated board. This improved compression resistance provided improved stacking strength.

[0087] It will also be understood that the word "a" or "an" is intended to mean

"one or more" or "at least one", and any singular form is intended to include plurals herein. [0088] It will be further understood that the term "comprise", including any variation thereof, is intended to be open-ended and means "include, but not limited to," unless otherwise specifically indicated to the contrary.

[0089] When a list of items is given herein with an "or" before the last item, any one of the listed items or any suitable combination of two or more of the listed items may be selected and used.

[0090] Of course, the above described embodiments are intended to be illustrative only and in no way limiting. The described embodiments are susceptible to many modifications of form, arrangement of parts, details and order of operation. The invention, rather, is intended to encompass all such modification within its scope, as defined by the claims.