Note: Descriptions are shown in the official language in which they were submitted.
2 1 67022
BACRGROUND OF THE l..~L.. lON
Field of the Invention:
This invention relates generally to the art of food
packaging and more partlcularly to a container for packag-
ing, storing and heating food. Such structures of this
type, generally, are constructed with near vertical side-
walls and a separate lid such that the trays are easily
nestable and remain stable when the lid is removed.
DescriDtion of the Related Art:
It is known, in paperboard food containers, to make
use of sidewall panels. An adhesive is placed between the
sidewall end portion areas of the sidewall panels in order
to construct a partition. This maintains a space between
the sidewalls and maintains heat insulation between the
compartments in the event that one compartment contains
warm food contents, while an adjacent compartment contains
cool food contents.
Exemplary of such prior art is U. S. Patent No.
5,265,796 ('796) to R. Gulliver et al., entitled "Plural
Compartment Carton Food Tray With Improved Corner
Construction." While the sidewalls provide a partition
between the various food contents of the tray, the
structure of the sidewalls and the partition is such that
the partition may not be stable after the lid is removed.
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If the partition is not stable after the lid is removed,
the food contents within the tray may spill over during the
consumption of the food from the tray.
Also, with respect to the ('796) reference, a plastic
film such as polyester (PE), polypropylene (PP), or
polyethylene terephthalate (PET) is laminated to the
paperboard. It is well known that this laminated film is
undesirable because when folded it contains pin holes in
the areas adjacent to the corners of the tray and lid which
are susceptible to contamination by outside influences.
Therefore, a more advantageous container would be one which
would remain stable after the lid is removed and included
a more desirable food contact coating.
In an apparent attempt to alleviate some of the
problems associated with the ('796) reference, the
invention disclosed in U. S. Patent No. 5,267,686 ('686) to
R. Gulliver et al., entitled, "Food Package Containing
Separate Trays Connected Together By A Single Lid
Structure" was developed. The ('686) patent illustrates an
adhesively adhered and inter-arranged relation between the
flange-engaging portions and the lower portions of the top
flaps with the portions of the trays represented by the
flanges and the lower portions of the sidewalls retaining
the assembly in a unitary package suitable for transpor-
tation and handling. While the package is suitable for
transportation and handling, the package cannot be nestable
due to the construction of the sidewalls. Also, the
coating is laminated as discussed earlier with respect to
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the ('796) patent. Therefore, a further advantageous
container would be one which is stable, nestable, and
contains a continuous food contact coating.
With respect to the use of a continuous coating,
commonly assigned U. S. Patent No. 5,356,070 ('070) to W.
R. Rigby, entitled "Partitioned Paperboard Food Tray"
depicts a continuous coating which is blow molded into a
partitioned paperboard food tray. However, the food tray
includes interior walls which form a partition that may
render the food tray unstable. Also, flanges located
around the perimeter of the food tray do not allow the food
tray to be pushed through a conventional plate freezer
without the food tray shingling and/or ~amming in the
freezer. Therefore, a still further advantageous food
container would be one which included the continuous
coating but at the same time provided a stable structure
which allowed the packages to be easily pushed through
conventional freezers.
It is apparent from the above that there is a need in
the art for a partitioned paperboard container which
includes a continuous, blow molded coating, and which is
nestable, but which at the same time can remain stable
after the lid is removed. It is the purpose of this
invention to fulfill this and other needs in the art in a
manner more apparent to the skilled artisan once given the
following disclosure.
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.
SUMMARY OF THE INVENTION
Generally, speaking, this invention fulfills these
needs by providing a partitioned paperboard food container,
wherein the container is comprised of: a partitioned tray
means including a paperboard sheet material tray base
having an interior surface lined with a continuous and
unlapped layer of a food contact coating applied to the
interior surface, wherein the base is formed into at least
two bottom panel areas; at least two internal wall panels
materially integral with each of the at least two bottom
panel areas such that the internal wall panels form a
partition in the tray; at least two external wall panels
materially integral with each of the at least two bottom
panel areas; a first and second top flange means located
adjacent to the at least two external wall panels; and a
lid means releasably attached to the tray means and
including a paperboard sheet material lid base having an
interior surface lined with a continuous and unlapped layer
of a food contact coating applied to the interior surface,
wherein the lid base includes a first and second wall
closure flap means operatively connected to the lid base
and adapted to overlap the first flange means wherein the
first wall closure flap means is operatively connected to
one of the at least two external wall panels and the second
wall closure flap means is operatively connected to another
of the at least two external wall panels and further
includes a first and second flap panel means located
substantially across an end of the partition for releasing
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the lld means from the tray means such that the first flap
panel means remains with the second wall closure flap means
when the lid means is released from the tray means and the
second flap panel means remains substantially across the
end of the partition when the lid means is released from
the tray means.
In certain preferred embodiments, the base is formed
into three bottom panel areas which requires three
partitions. Also, the wall closure flap means may extend
down over all of the exterior wall panels. Finally, the
wall closure flap means are attached to the external wall
panels by an adhesive.
In another further preferred embodiment, the location
of the wall closure flaps provides stability to the
container both before and after the lid is removed.
The preferred container, according to this invention,
offers the following advantages: ease of assembly;
excellent stability; good durability; and excellent
economy. In fact, in many of the preferred embodiments,
these factors of stability and economy are optimized to an
extent that is considerably higher than heretofore achieved
in prior, known paperboard containers.
The above and other features of the present invention
which will become more apparent as the description proceeds
are best understood by considering the following detailed
description in conjunction with the accompanying drawings,
wherein like characters represent like parts throughout the
several views and in which:
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A BRIEF D-SCRIPTION OF THE DRAWINGS
FIGURE l is a pictorial view of a divided food tray
container with the lid unattached, according to the present
lnvention;
FIGURE 2 is a pictorial view of the divided food tray
with the lid attached and released in the front, according
to the present invention;
FIGURE 3 is a pictorial view of another embodiment of
a divided food tray container with the lid unattached,
according to the present invention; and
FIGURE 4 is a pictorial view of another embodiment of
the divided food tray container with the lid unattached,
according to the present invention.
DETAT~n DESCRIPTION OF THE lr.~h~llON
The basic substrate material for the present invention
is a machine made paperboard which may range in thickness
from 0.1778 mm to 0.889 mm (0.007 to 0.035 inches). In
some cases, it may be desirable to coat the paperboard web
stock on that web side to be formed to the interior of the
tray with a film of extruded press-applied polymer selected
on the basis of chemical and adhesive receptivity in those
cases where the interior surface is subsequently applied
with a blow molded polymer. However, due to the fact that
extruded blow molded polymers of the type and nature
anticipated by the present invention are applied to
paperboard blank mold liners at various temperatures,
viscosities and pressures, many tie films of paperboard
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substrates become unnecessary. In this manner, the blow
molded polymer bonds deeply and securely to the paperboard
surface.
Those of ordinary skill in the art understand the
economic value to consumer packaging arising from the
qualities of graphics that may be press-applied to a
paperboard web. Moreover, the web may be printed and die
cut into individual tray blanks in a continuous machine
feed operation. Resultantly, display shelf graphics may be
directly applied to the exterior side wall surface of the
package that is opposite the interior side wall surface in
direct contact with the package contents. For such an
application, no outer packaging or post-fill labeling is
required.
Proceeding from the foregoing understandings, Figure
1 illustrates container 2 which includes, in part, lid 4
and divided tray 20. More particularly, a lid 4 includes,
conventional polymeric coating 6, wall closure flap 8,
panels 9 and 10 and tear line 12.
With respect to tray 20, tray 20 includes, bottom
panels 22, internal walls 24, external walls 26, flanges 28
and 30, patterned adhesive area 32, and partition 34. It
should be noted that flanges 28 extend away from internal
walls 24 while flanges 30 extend toward internal walls 24.
Also, another patterned adhesive area 32 is located on the
back of tray 20.
With respect to Figure 2, Figure 2 shows that lid 4 is
attached to tray 20 by wall closure flap 14 and adhesive
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area 32 (in back of tray 20). Also, as shown in Figure 2,
wall closure flap 8 has been released from tray 20 in that
tear line 12 has been activated according to conventional
techniques and panel 10 remains on tray 20. In this
manner, panel 10 spans across an end of partition 34 to add
structural rigidlty to tray 20. The location of panel 10
across the end of partition 34 acts as a "brace" such that
tray 20 cannot bend and/or flex along internal walls 24 at
partition 34 either before or after the tray is opened.
Figure 3 shows container 50. In particular, container
50 includes, in part, lid 4 and tray 52. Lid 4,
preferably, is constructed in the same manner as the lid 4
shown in the Figures 1 and 2.
Tray 52 includes, in part, bottom panels 54, internal
walls 56, external walls 58, flanges 60 and 62, patterned
adhesive areas 64, and partition 66. Also, another
patterned adhesive area 64 is located on the back of
tray 52.
As discussed earlier, with respect to Figure 2, lid 4
is adhered to tray 52 along adhesive areas 64 (located on
the back of tray 52). In this manner, wall closure flap 8
spans across an end of partition 66 to add structural
rigidity to container 50.
After the food contents in container 50 are heated by
conventional heating techniques, tear line 12 on lid 4 is
conventionally activated such that lid 4 is released from
tray 52. Upon the release of lid 4 from tray 52, lid 4 and
panel 9 are raised above tray 52. However, panel 10
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remains adhered to tray 52 such that panel 10 extends
across an end of partition 66 found between internal walls
56 in order to add structural rigidity to tray 52 during
the consumption of the food contents within tray 52.
With the respect to Figure 4, there is illustrated
container 100. In particular, container 100 includes, in
part, lid 104 and tray 52. Tray 52, preferably, is
constructed in the same manner as tray 52 in Figure 3,
except that flange 60 is folded inward towards internal
walls 56.
Lid 104 includes in part, conventional polymer coating
106 and wall closure flaps 108. In particular, wall flaps
108 include, panels 109 and 110 and conventional tear
lines 112.
With respect to the constructlon of container 100,
after the food contents within container 100 are heated by
conventional heating techniques, the consumer removes lid
104 along tear line 112. After tear lines 112 are
activated, panels 110 remain adhered to tray 52 across an
end of partition 66 such that panels 110 add structional
rigidity to tray 52 while the food contents within tray 52
are being consumed.
With respect to the construction of containers 2, 50,
and 100 there are several important features to keep in
mind. First, flanges 30 (Figure 1), 62 (Figure 3), and 60
and 62 (Figure 4) are folded inwardly towards their
respective internal side walls such that the containers 2,
50 and 100, respectively, when completely constructed, can
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be pushed through a conventional plate freezer on their
near vertical sides. Second, this construction allows the
containers to be stacked on a shelf on their near vertical
sides. Third, the location of the panels 10 and 110 across
ends of partitions 34 and 66, respectively, provide
improved structional rigidity to the containers. In
particular, without the panels 10 and 110 being located
across ends of the partitions, the trays 20 and 52 could
easily bend or twist at the partitions. Even when the
trays lids are removed, the panels, which are adhesively
attached to the external side walls, remain in place to
provide the desired tray rigidity.
Once given the above disclosure, many other features,
modifications or improvements will become apparent to the
skilled artisan. Such features, modifications or
improvements are therefore, considered to be a part of this
invention, the scope of which is to be determined by the
following claims.
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