Reclosable food container

Information

  • Patent Grant
  • 6676010
  • Patent Number
    6,676,010
  • Date Filed
    Wednesday, September 18, 2002
    22 years ago
  • Date Issued
    Tuesday, January 13, 2004
    21 years ago
Abstract
A reclosable food container is created from a unitary blank. The container includes a bottom panel, a pair of opposing end panels extending from the first bottom panel, a lateral side panel extending from the first bottom panel, and an opposing side panel extending from the bottom panel on an opposing side to the lateral side panel. The container also includes a plurality of foldable gussets, where each gusset hingedly connects a side panel-end panel pair. The container also includes a lid extending from the lateral side panel, where the lid includes a top panel and a tuck flap. There is a score line between at least one of the lateral side panel and the top panel, and the top panel and the tuck flap. The score line has a ratio of penetration between about 0.1 and about 0.9.
Description




BACKGROUND




1. Field




A reclosable food container suitable for use in the take-out food industry. More particularly, an easily openable and reclosable food container having a cavity which is erected from a single unitary blank.




2. Relevant Art




The expansion of the take-out and prepared food industry over the last several years has increased demand for suitable containers. The Chinese food pail is well-known in the take-out food industry. It is preconstructed at the manufacture plant by folding the pre-cut blank and fastening the gussets with glue or metallic wire. This simplifies use by the food seller who need merely fill the container and close the lid. These Chinese food pails typically have a deep narrow configuration which makes them unsuitable for storage of food not intended to intermingle. Moreover, such pails uniformly have a four-panel lid structure which requires four different folding operations and the use of both hands to achieve closure.




Another type of food carton is fashioned in a shallower configuration. The same four-fold lid structure is also employed by this type of container.




Still another type of food container is fashioned in the form of an open tray for storing a predetermined amount of food. It is erected at the point of purchase from a pre-cut, pre-scored carton blank. These blanks are typically erected by manually performing numerous time consuming folding and tucking operations at the point of sale. The resulting container often leaks at the corner formed by interlocking tabs and slots. Some variations employ glue to secure the adjacent panels, but leaking remains a problem. Such containers are unsatisfactory for packaging many prepared or take-out foods.




In view of the foregoing, it would be desirable to have a reclosable food container with a simplified lid closure.




SUMMARY




A reclosable food container is created from a unitary blank. The container includes a bottom panel, a pair of opposing end panels extending from the first bottom panel, a lateral side panel extending from the first bottom panel, and an opposing side panel extending from the bottom panel on an opposing side to the lateral side panel. The container also includes a plurality of foldable gussets, where each gusset hingedly connects a side panel-end panel pair. The container also includes a lid extending from the lateral side panel, where the lid includes a top panel and a tuck flap. There is a score line between at least one of the lateral side panel and the top panel, and the top panel and the tuck flap. The score line has a ratio of penetration between about 0.1 and about 0.9.




A method of making a reclosable food container from a unitary blank includes scoring the unitary blank with a plurality of score lines and a plurality of fold lines. At least two of the score lines define a top panel and a tuck flap of a lid. The score lines have a ratio of penetration between about 0.1 and about 0.9. The method also includes folding along two pairs of substantially parallel fold lines that define a bottom panel. The method also includes folding along four sets of fold lines, each set defining a gusset extending between pairs of adjacent walls of a cavity, and adhering each gusset to an outer surface of one of the adjacent walls. The lid extends from a wall of the cavity.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a blank of a food container of a first embodiment.





FIG. 2

is a food container assembled from the blank shown in

FIG. 1

nested with a second food container.





FIG. 3

shows a food container of one embodiment with the top closed.





FIG. 4

shows a sectional view of a container of

FIG. 2

with gussets in phantom view.





FIG. 5

shows a partial sectional view of the container of FIG.


4


.





FIG. 6

shows a portion of the tuck flap.





FIG. 7

shows a portion of the opposing side panel.





FIG. 8

shows a section of the score line between the side panel and the top panel.





FIG. 9

shows a sectional view of the score line along the line


9





9


of FIG.


8


.











DETAILED DESCRIPTION





FIG. 1

shows blank


10


of a food container of a first embodiment. Blank


10


from which a container may be formed may be punched as a unitary blank from a single sheet of paperboard material suitable for holding, heating, and cooking food. Any paperboard which can withstand the heat generated by a microwave or convection oven is suitable. Suitable paperboard is commercially available and well known in the trade. In one embodiment, paperboard may be coated and/or laminated with a material (for example a polymer) so that the container can hold liquids.




Blank


10


has substantially rectangular bottom panel


1


which is defined by first pair of substantially parallel fold lines


11


and second pair of substantially parallel fold lines


13


,


14


. Pair of end panels


2


extend from first bottom panel


1


along fold lines


11


. Pair of splash guard flaps


8


extend from pair of end panels


2


along score lines


18


. First lateral side panel


3


extends from first bottom panel


1


along fold line


13


. Upper edge of first lateral side panel


3


is defined by score line


15


. A lid that includes top panel


5


and tuck flap


7


extends therefrom. Score line


17


delineates the transition between top panel


5


and tuck flap


7


. Score line


17


terminates at either end in locking slits


27


. Flap


7


also includes locking slot mechanism


62


.




Opposing side panel


4


extends from first bottom panel


1


along fold line


14


. Opposing side panel


4


includes locking tab mechanism


64


.




Generically, end panels


2


, lateral side panel


3


, and opposing side panel


4


are referred to as walls, four gussets


6


extending between adjacent pairs of walls (side-end pairs). Each gusset


6


is defined by a pair of wall edge defining fold lines


12


and at least one interior fold line


19


. By appropriately folding along the fold line, a cavity having a lid is defined.




In one embodiment, blank


10


is punched and primarily assembled (e.g., gussets glued) at a manufacturing facility prior to shipment to an end user.





FIG. 2

shows a container assembled from blank


10


shown in FIG.


1


. Gussets


6


are folded and adhered to end panels


2


. When the lid, e.g., including top panel


5


and tuck flap


7


, is moved to a closed orientation, tuck flap


7


frictionally engages at least one of opposing side panel


4


and/or pair of end panels


2


. Locking slits


27


may also engage splash guard flaps


8


. In addition, locking tab mechanism


64


may slidingly engage with locking slot mechanism


62


. One or more of these engagements act to maintain closure so that food placed within the cavity will be retained.




The fact that the cavity is formed from a contiguous sheet prevents leaking at the gussets


6


as long as a substantially upright orientation is maintained.




In one embodiment, one or more walls of the cavity are trapezoidal. Thus, end panels


2


, lateral side panel


3


, and/or opposing side panel


4


slope downward from their upper edges to their intersection with bottom panel


1


. In another embodiment, score lines


18


are longer than fold lines


11


. This permits the assembled containers to be nested for shipping and storage so as to require less space during such shipping and storage.




Once blank


10


is punched from a suitable paperboard sheet and appropriately scored, to assemble the container of a first embodiment, end panels


2


, lateral side panel


3


, and opposing side panel


4


are folded upward along fold lines


11


,


13


, and


14


such that end panels


2


, lateral side panel


3


, and opposing side panel


4


define a cavity with bottom panel


1


.




Gussets


6


are folded along fold line


19


such that each gusset


6


extends outward from a defined cavity. Each gusset


6


is then folded to be adjacent to an external surface of end panels


2


and may be attached thereto, in one embodiment, with a suitable adhesive. It is also contemplated that gussets


6


may be adhered to the external surface of side panels


3


,


4


. Suitable adhesives are well-known in the art.




Splash guard flaps


8


are folded inward so as to extend over a portion of the cavity defined by end panels


2


, lateral side panel


3


, and opposing side panel


4


(walls


2


-


4


) and bottom panel


1


. Score line


17


may be creased so that when top panel


5


is folded along score line


15


, tuck flap


7


is positioned to engage opposing side panel


4


.





FIG. 3

shows a container assembled from blank


10


of

FIG. 1

with the lid, including top panel


5


and tuck flap


7


, moved to a closed orientation. Tuck flap


7


frictionally engages at least one of opposing side panel


4


and/or pair of end panels


2


. Locking slits


27


may also engage splash guard flaps


8


. In addition, locking tab mechanism


64


is shown slidingly engaged with locking slot mechanism


62


.





FIG. 4

shows a sectional view of the container of FIG.


3


. In this view, the frictional engagement between tuck flap


7


and opposing side


4


is shown. Gussets


6


are shown in phantom view.





FIG. 5

shows a partial sectional view of the container of

FIG. 4

along line


5





5


in which gussets


6


are shown adhered to end panel


2


by adhesive


26


. In one embodiment, adhesive


26


does not degrade when reheated, e.g., a microwave oven. Suitable adhesives are well known in the art.





FIG. 6

illustrates a portion of tuck flap


7


with locking slot mechanism


62


. Locking slot mechanism


62


includes horizontal portion


81


and two downward portions


83


,


85


. Horizontal portion


81


makes angle Δ


82


with downward portion


83


. Horizontal portion


81


makes angle Ω


84


with downward portion


85


. Horizontal portion


81


has top width W


3




102


. Locking slot mechanism


62


has total width W


4




104


which includes horizontal portion


81


and downward portions


83


,


85


. Locking slot mechanism


62


has height H


2




86


.




In one embodiment, top width W


3




102


is between about 0.25 and about 2.5 inches. In another embodiment, top width W


3




102


is between about 0.5 and about 2.0 inches. In another embodiment, top width W


3




102


is about 1.5 inches.




In one embodiment, total width W


4




104


is between about 0.25 and about 2.5 inches. In another embodiment, total width W


4




104


is between about 0.5 and about 2.0 inches. In another embodiment, total width W


4




103


is about 1.5 inches.




In one embodiment, the ratio of top width W


3




102


to total width W


4




104


is between about 0.5 and about 1.0. In another embodiment, the ratio of top width W


3




102


to total width W


4




104


is between about 0.75 and about 1.0. In another embodiment, the ratio between top width W


3




102


and total width W


4




104


is about 1.0.




In one embodiment, angle Δ


82


is between about 60° and about 120°. In another embodiment, angle Δ


82


is between about 75° and about 105°. In another embodiment, angle Δ


82


is about 90°.




In one embodiment, angle Ω


84


is between about 60° and about 120°. In another embodiment, angle Ω


84


is between about 75° and about 105°. In another embodiment, angle Ω


84


is about 90°.




In one embodiment, height H


2


is between about 0.1 and about 1.0 inches. In another embodiment, height H


2




86


is between about 0.15 and about 0.5 inches. In another embodiment, height H


2


is about 0.25 inches.





FIG. 7

illustrates a portion of opposing side panel


4


with locking tab mechanism


64


. Locking tab mechanism


64


includes horizontal portion


67


and downward portions


69


and


71


. On either side of tab portion


66


are two indentations


68


,


70


. Tab portion


66


has angle β


74


between horizontal portion


67


and downward portion


69


. Tab portion


66


has angle α


72


between horizontal portion


67


and downward portion


71


. In one embodiment, tab portion


66


has a trapezoidal shape.




Tab portion


66


has height H


1




76


. Tab portion


66


has width W


1




78


at the top, along horizontal portion


67


, and width W


2




80


(that includes horizontal portion


67


and downward portions


69


,


71


) at the bottom.




In one embodiment, top width W


1




78


is between about 0.25 and about 2.0 inches. In another embodiment, top width W


1




78


between about 0.5 and about 2.0 inches. In another embodiment, top width W


1




78


is about 1.25 inches.




In one embodiment, bottom width W


2




80


is between about 0.25 and about 2.5 inches. In another embodiment, bottom width W


2




80


is between about 0.5 and about 2.0 inches. In another embodiment, bottom width W


2




80


is about 1.5 inches.




In one embodiment, angle β


74


is between about 90° and about 150°. In another embodiment, angle β


74


is between about 100° and about 140°. In another embodiment, angle β


74


is about 120°.




In one embodiment, angle β


72


is between about 90° and about 150°. In another embodiment, angle α


72


is between about 100° and about 140°. In another embodiment, angle α


72


is about 120°.




In another embodiment, the ratio between top width W


1




78


and bottom width W


2




80


is between about 0.5 and about 1.0. In another embodiment, the ratio between top width W


1




78


and bottom width W


2




80


is between about 0.6 and about 0.9. In another embodiment, the ratio between top width W


1




78


and bottom width W


2




80


is about 0.75.




In one embodiment, locking slot mechanism


62


and locking tab mechanism


64


can be engaged with each other with one hand when closing the food container. In another embodiment, locking slot mechanism


62


and locking tab mechanism


64


can be disengaged from each other when opening the food container. In another embodiment, locking slot mechanism


62


and locking tab mechanism


64


can be engaged with each other with a single finger when closing the food container. In another embodiment, locking slot mechanism


62


and locking tab mechanism


64


can be disengaged from each other with a single finger when opening the food container.





FIG. 8

illustrates a section of score line


15


between side panel


3


and top panel


5


. Score line


15


includes a configuration having scored portions


90


and unscored portions


92


. Scored portions


90


have length L


1




94


. Unscored portions


92


have a length L


2




96


.




In one embodiment, length L


1




94


is between about 0.1 and about 2.0 inches. In another embodiment, length L


1




94


is between about 0.2 and about 1.5 inches. In another embodiment, length L


1




94


is between about 0.5 and about 1.25 inches. In another embodiment, length L


1




94


is about 1.0 inches.




In one embodiment, length L


2




96


is between about 0.01 and about 0.5 inches. In another embodiment, length L


2




96


is between about 0.05 and about 0.3 inches. In another embodiment, length L


2




96


is between about 0.1 and about 0.25 inches. In another embodiment, length L


2




96


is about 0.2 inches.





FIG. 9

shows a sectional view along the line


9





9


of FIG.


8


.

FIG. 9

shows a portion of score line


15


with scored portions


90


and unscored portions


92


. Scored portions


90


have length L


1




94


. Unscored portions


92


have length L


2




96


. Scored portions


90


have depth of scoring D


1




98


. The paperboard has thickness D


2




99


. The ratio of penetration is defined as the ratio of depth of scoring D


1




98


divided by thickness of the paperboard D


2




99


.




In one embodiment, the ratio of penetration of score line


15


is between about 0.1 and about 0.9. In another embodiment, the ratio of penetration of score line


15


is between about 0.2 and about 0.8. In another embodiment, the ratio of penetration of score line


15


is between about 0.3 and about 0.7. In another embodiment, the ratio of penetration of score line


15


is between about 0.45 and about 0.55. In another embodiment, the ratio of penetration of score line


15


is about 0.5.




While

FIGS. 8 and 9

illustrate score line


15


between side panel


3


and top panel


5


, the discussion of

FIGS. 8 and 9

is also applicable to score lines


17


and


18


.




In one embodiment, score line


17


has a ratio of penetration the same as or similar to score line


15


. In another embodiment, score line


17


has a different ratio of penetration than score line


15


, but score line


17


meets one or more of the parameters discussed above for score line


15


.




In one embodiment, score line


18


has a ratio of penetration the same as or similar to score line


15


and/or score line


17


. In another embodiment, score line


18


has a different ratio of penetration than score line


15


and/or score line


17


, but score line


18


meets one or more of the parameters discussed above for score line


15


.




In one embodiment, fold lines


11


,


12


,


13


,


14


, and


19


have ratio of penetration less than score lines


15


,


17


, and


18


.




In one embodiment, fold lines


11


,


12


,


13


,


14


, and


19


have a ratio of penetration between about 0.0 and about 0.4. In another embodiment, fold lines


11


,


12


,


13


,


14


, and


19


have a ratio of penetration between about 0.01 and about 0.2. In another embodiment, fold lines


11


,


12


,


13


,


14


, and


19


have a ratio of penetration of about 0.05.




In one embodiment, fold lines


11


,


12


,


13


,


14


, and


19


may have a lower ratio of penetration since the fold lines define the container, and are not used to open or close the lid of the container. In one embodiment, score lines


15


,


17


, and


18


may have a higher ratio of penetration than fold lines, since score lines


15


,


17


, and


18


are used in the operation of opening and closing the lid of the container.




In one embodiment, score line


15


has a ratio of penetration less than about 1.0, so that there is a lessened likelihood of leakage through score line


15


. In another embodiment, score line


17


has a ratio of penetration less than about 1.0, so that there is a lessened likelihood of leakage through score line


17


. In one embodiment, score line


15


has a ratio of penetration that makes closing and opening the lid easier. In another embodiment, score line


15


has a ratio of penetration so that the lid folds flatter than when in a closed orientation. In another embodiment, score line


15


has a ratio of penetration so that the lid has a flat shape rather than a bowed shape.




In another embodiment, fold lines


11


,


12


,


13


,


14


, and


19


and score lines


15


,


17


, and


18


have a ratio of penetration so that the reclosable food container has a cleaner look. In another embodiment, fold lines


11


,


12


,


13


,


14


, and


19


and score lines


15


,


17


, and


18


have a ratio of penetration so that the food container is more esthetically pleasing. In another embodiment, fold lines


11


,


12


,


13


,


14


, and


19


and score lines


15


,


17


, and


18


have a ratio of penetration so that the food container has a stronger structure. In another embodiment, locking slot mechanism


62


and locking tab mechanism


64


engage when the lid is in a closed orientation so that the food container has a stronger structure. In another embodiment, fold lines


11


,


12


,


13


,


14


, and


19


and score lines


15


,


17


, and


18


have a ratio of penetration, and locking slot mechanism


62


and locking tab mechanism


64


engage when the lid is in a closed orientation so that the food container has a stronger structure.




In one embodiment, a reclosable food container is created from unitary blank


10


. The container includes bottom panel


1


, pair of opposing end panels


2


extending from bottom panel


1


, lateral side panel


3


extending from bottom panel


1


, opposing side panel


4


extending from bottom panel


1


on an opposing side to lateral side panel


3


. Opposing side panel


4


includes locking tab mechanism


64


. The container also includes a plurality of foldable gussets


6


, each gusset


6


hingedly connecting a side panel-end panel pair. The container also includes a lid extending from lateral side panel


3


. The lid includes top panel


5


and tuck flap


7


. Tuck flap


7


includes locking slot mechanism


62


. The lid engages at least one of opposing side


4


, pair of opposing end panels


2


, and locking tab mechanism


64


when in a closed orientation. The container also includes score line


15


(between lateral side panel


3


and top panel


5


) or score line


17


(between top panel


5


and tuck flap


7


), where score line


15


and/or


17


has a ratio of penetration between about 0.2 and about 0.8.




In another embodiment, each opposing end panel


2


of the food container also includes splash guard flap


8


extending therefrom.




In another embodiment, tuck flap


7


of the lid of the food container engages splash guard flaps


8


when the lid is in a closed orientation.




In another embodiment, the reclosable food container also includes pair of locking slits


27


formed at opposite edges of a junction between top panel


5


and tuck flap


7


, where locking slits


27


increase a retention strength of the engagement between respective opposing splash guard flaps


8


when the lid is in a closed orientation. In another embodiment, side panels


3


,


4


and end panels


2


of the food slope upward at a predetermined angle from bottom panel


1


so that a pair of food containers are nestable one within the other.




In another embodiment, respective ones of panels


1


,


2


,


3


, and/or


4


of the food container are defined on blank


10


by fold lines


11


,


12


,


13


,


14


, and/or


19


. In another embodiment, score lines


15


,


17


, and/or


18


of the food container have a ratio of penetration between about 0.3 and about 0.7.




In another embodiment, score lines


15


,


17


, and/or


18


of the food container have a ratio of penetration between about 0.45 and about 0.55.




In another embodiment, score lines


15


,


17


, and/or


18


of the food container have a ratio of penetration of about 0.5.




In another embodiment, score lines


15


,


17


, and/or


18


of the food container have a ratio of length


96


of unscored portion


92


to length


94


of scored portion


90


between about 0.1 and about 0.5.




In another embodiment, score lines


15


,


17


, and/or


18


of the food container have a ratio of length


96


of unscored portion


92


to length


94


of scored portion


90


between about 0.15 and about 0.25.




In another embodiment, score lines


15


,


17


, and/or


18


of the food container have a ratio of length


96


of unscored portion


92


to length


94


of scored portion


90


of about 0.2.




In one embodiment, a method of making a reclosable food container from unitary blank


10


includes scoring unitary blank


10


with a plurality of score lines


15


,


17


, and/or


18


and a plurality of fold lines


11


,


12


,


13


,


14


, and/or


19


. At least two of score lines


15


,


17


, and/or


18


define top panel


5


and tuck flap


7


of a lid. Score lines


15


,


17


, and/or


18


have a ratio of penetration between about 0.2 and about 0.8. The method also includes folding along two pairs of substantially parallel fold lines


11


,


13


,


14


that define bottom panel


1


. The method also includes folding along four sets of fold lines


12


and/or


19


, each set


12


and/or


19


defining gusset


6


extending between pairs of adjacent walls


2


-


3


or


2


-


4


of a cavity. The method also includes adhering each gusset


6


to an outer surface of one of the adjacent walls


2


,


3


, and/or


4


. The lid extends from wall


3


of the cavity so as to permit engagement of at least one of opposing wall


4


and locking tab mechanism


64


if folded about score lines


15


,


17


that define the lid.




In another embodiment, the container of the method also includes locking slits


27


at a junction between tuck flap


7


and top panel


5


of the lid, and the method also includes engaging pair of splash guard panels


8


with locking slits


27


.




In the foregoing specification, the container has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes can be made thereto without departing from the broader spirit and scope as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. Therefore, the scope should be limited only by the appended claims.



Claims
  • 1. A reclosable food container created from a unitary blank, the container comprising:a bottom panel; a pair of opposing end panels extending from the bottom panel; a lateral side panel extending from the bottom panel; an opposing side panel extending from the bottom panel on an opposing side to the lateral side panel; a plurality of foldable gussets, each gusset hingedly connecting a side panel-end panel pair; a lid extending from the lateral side panel, the lid comprising a top panel and a tuck flap; a score line between at least one of the lateral side panel and the top panel, and the top panel and the tuck flap, wherein the score line has a ratio of penetration between about 0.1 and about 0.9.
  • 2. The food container of claim 1 wherein each opposing end panel further comprises a splash guard flap extending therefrom.
  • 3. The food container of claim 2 wherein the tuck flap of the lid engages the splash guard flaps when the lid is in a dosed orientation.
  • 4. The reclosable food container of claim 3 further comprising:a pair of locking slits formed at opposite edges of a junction between the top panel and the tuck flap; wherein the locking slits increase a retention strength of the engagement between the respective opposing splash guard flaps when the lid is in a closed orientation.
  • 5. The food container of claim 1 wherein the side panels and end panels slope upward at a predetermined angle from the bottom panel such that a pair of food containers are nestable one within another.
  • 6. The food container of claim 1 wherein respective ones of the panels are defined on the blank by fold lines.
  • 7. The food container of claim 1 wherein the score line has a ratio of penetration between about 0.3 and about 0.7.
  • 8. The food container of claim 1 wherein the score line has a ratio of penetration between about 0.45 and about 0.55.
  • 9. The food container of claim 1 wherein the score line has a ratio of penetration about 0.5.
  • 10. The food container of claim 1 wherein the score line has a ratio of a length between an unscored portion and a scored portion between about 0.1 and about 0.5.
  • 11. The food container of claim 1 wherein the score line has a ratio of a length between an unscored portion and a scored portion between about 0.15 and about 0.25.
  • 12. The food container of claim 1 wherein the score line has a ratio of a length between an unscored portion and a scored portion of about 0.2.
  • 13. The food container of claim 1, wherein the opposing side panel further comprises a locking tab mechanism, and the tuck flap further comprises a locking slot mechanism.
  • 14. The food container of claim 13, wherein the lid engages at least one of the opposing side, the pair of opposing hinge panels, and the locking tab mechanism when in a closed orientation.
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