U.S. patent application number 12/102703 was filed with the patent office on 2009-01-01 for container insert incorporating thermally insulative panels.
This patent application is currently assigned to Nanopore, Inc.. Invention is credited to Brian Glover, Kevin H. Roderick, Douglas M. Smith.
Application Number | 20090001086 12/102703 |
Document ID | / |
Family ID | 40159138 |
Filed Date | 2009-01-01 |
United States Patent
Application |
20090001086 |
Kind Code |
A1 |
Roderick; Kevin H. ; et
al. |
January 1, 2009 |
CONTAINER INSERT INCORPORATING THERMALLY INSULATIVE PANELS
Abstract
A container insert for providing a thermally insulated
enclosure. The container insert includes a bottom panel, side
panels and end panels that are interconnected by a plastic backing
sheet. The side panels and end panels can be pivoted upwardly to
form side walls and end walls. The plastic backing sheet covers the
seams between adjacent insulation panels to provide a moisture
barrier. The plastic backing sheet can also urge adjacent panels
together to reduce the gap between adjacent panels and improve
thermal performance.
Inventors: |
Roderick; Kevin H.;
(Albuquerque, NM) ; Glover; Brian; (Albuquerque,
NM) ; Smith; Douglas M.; (Albuquerque, NM) |
Correspondence
Address: |
MARSH, FISCHMANN & BREYFOGLE LLP
8055 East Tufts Avenue, Suite 450
Denver
CO
80237
US
|
Assignee: |
Nanopore, Inc.
Albuquerque
NM
|
Family ID: |
40159138 |
Appl. No.: |
12/102703 |
Filed: |
April 14, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60911386 |
Apr 12, 2007 |
|
|
|
Current U.S.
Class: |
220/592.2 ;
206/527 |
Current CPC
Class: |
B65D 81/3851
20130101 |
Class at
Publication: |
220/592.2 ;
206/527 |
International
Class: |
B65D 83/72 20060101
B65D083/72 |
Claims
1. A container insert, comprising: a base insulation panel having a
top surface, a bottom surface and a peripheral edge surface; first
and second side insulation panels each having a top surface, a
bottom surface and a peripheral edge surface, where the side panels
are attached to the base panel in spaced-apart relation on opposite
sides of the base panel by a plastic backing sheet; first and
second end insulation panels each having a top surface, a bottom
surface and a peripheral edge surface, where the end panels are
attached to the base panel in spaced-apart relation on opposite
ends of the base panel by a plastic backing sheet; wherein each of
the side panels and the end panels can be pivoted upwardly toward
the base panel to contact the base panel along a seam and form side
walls and end walls, wherein the plastic backing sheet covers at
least a portion of each seam between the base panel and the side
panels and between the base panel and the end panels, to form an
enclosure having a base, side walls, end walls and a top
opening.
2. A container insert as recited in claim 1, wherein said plastic
backing sheet is heat welded to said insulation panels.
3. A container insert as recited in claim 2, wherein said plastic
backing sheet comprises a thermoplastic film layer.
4. A container insert as recited in claim 1, wherein said end
panels and side panels are spaced apart from said base panel of a
distance approximately equal to the thickness of the base
panel.
5. A container insert as recited in claim 1, further comprising a
thermally insulated lid that is adapted to fit over the top
opening.
6. A container insert as recited in claim 1, wherein said plastic
backing sheet comprises a plastic film that is substantially
impermeable to water vapor.
7. A container insert as recited in claim 1, wherein said plastic
backing sheet comprises a laminate polymer structure.
8. A container insert as recited in claim 7, wherein said plastic
backing sheet comprises a thermoplastic film.
9. A container insert as recited in claim 1, wherein said
insulation panels comprise vacuum insulation panels.
10. A container insert as recited in claim 9, wherein said vacuum
insulation panels comprise a core material and a barrier film
surrounding the core material, and wherein the barrier film
comprises a plastic film.
11. A container insert as recited in claim 10, wherein said barrier
film consists essentially of polymeric materials.
12. A container insert as recited in claim 11, wherein said barrier
film is a laminate film that comprises at least a first polymer
film layer and a second polymer film layer.
13. A container insert as recited in claim 12, wherein said first
polymer film layer comprises polyethylene and said second polymer
film layer comprises a material selected from the group consisting
of ethylene vinyl alcohol (EvOH), polyamide, polyethylene
terephthalate (PET) and polyvinylidene chloride (PVDC).
14. A container insert as recited in claim 1, further comprising
means for removably attaching said plastic backing sheet to an
exterior surface of said end panels.
15. A container insert as recited in claim 14, wherein the
attachment means comprises hook and loop fasteners.
16. A method for shipping a product, comprising the step of
providing a container insert as recited in claim 1, placing the
container insert within a shipping container, placing a product
within the container insert, placing a lid on the container insert
and transporting the shipping container to a desired location.
17. A method as recited in claim 16, further comprising cooling the
product cavity defined by the shipping container insert.
18. A container insert, comprising: a base insulation panel having
an interior surface, an exterior surface and a peripheral edge
surface; first and second side insulation panels transversely
disposed at opposite sides of the base panel to form side walls,
each side panel having an interior surface, an exterior surface and
a peripheral edge surface; first and second end insulation panels
transversely disposed at opposite ends of the base panel to form
end walls, each end panel having an interior surface, an exterior
surface and a peripheral edge surface; and a plastic backing sheet
disposed around at least a portion of the exterior surfaces of the
base panel, side panels and end panels; wherein the plastic backing
sheet covers at least a portion of the seams between the base panel
and the side panels and between the base panel and the end panels,
and covers at least a portion of the seams between adjacent side
panels and end panels such that the plastic backing sheet urges
adjacent panels together along the seams.
19. A container insert as recited in claim 18, wherein each of said
base panel, side panels and end panels is a vacuum insulation
panel.
20. A container insert as recited in claim 18, wherein said plastic
backing sheet is a laminate polymer film comprising at least first
and second polymer layers.
21. A container insert as recited in claim 18, wherein said plastic
backing sheet is heat welded to said insulation panels.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application Ser. No. 60/911,386 entitled "CONTAINER INSERT
INCORPORATING THERMALLY INSULATIVE PANELS", filed Apr. 12, 2007,
the disclosure of which is incorporated herein by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to the field of thermally
insulated containers that are adapted for the packaging,
containment and/or transport of temperature sensitive goods.
[0004] 2. Description of Related Art
[0005] Insulated containers having thermally insulated walls are
utilized for the containment and/or transport of goods that can be
damaged or otherwise rendered unsuitable for use if exposed to
temperatures outside of a particular temperature range. Thermal
insulation can be used to maintain a desired temperature within the
container despite increases or decreases in the exterior (ambient)
temperature.
[0006] For example, the shipment of products that must have their
temperature maintained within a specific range below ambient is one
of the fastest growing market segments in the modern shipping
industry. This growth is driven by a number of factors including
widespread concerns about safety in the cold food distribution
chain, increasing numbers of pharmaceutical and life sciences
products which must have their temperature maintained within
certain limits, the rapid growth in high-value specialty chemicals
such as those used in the semiconductor industry, the increasing
number of sophisticated medical tests which require the shipment of
patient specimens to an external laboratory, the increased number
of clinical trials associated with new pharmaceutical discovery and
the increased delivery of products directly to the customer as a
result of Internet ordering.
[0007] This field is generally referred to as controlled
temperature packaging (CTP). CTP can be segmented by the target
temperature range, namely: frozen (below 0.degree. C.); 2.degree.
C. to 8.degree. C.; and less than ambient (e.g., less than
30.degree. C.). In addition, CTP may be segmented by container
size, namely: greater than pallet; one cubic foot to pallet; and
less than one cubic foot. The one cubic foot to pallet size segment
is dominated by systems using ice (e.g., frozen gel packs) and/or
dry ice as a coolant where the containers are insulated using
expanded polystyrene (EPS). The market segment for containers less
than about one cubic foot in size is currently very limited due to
the need for a small, lightweight cooling mechanism and due to the
need to use relatively thin insulating walls to maximize the
available space for the product cavity.
[0008] A relatively simple thermally-insulated container system
includes a cardboard box into which EPS sheets have been cut and
placed. The container is then filled with dry ice in which, for
example, frozen fish is shipped. A more sophisticated approach is a
validated system consisting of custom molded EPS forms in a rigid
box with both frozen and warm gel packs, the combination of which
has been tested through a range of temperature cycles for specified
thermal properties. Such a validated system can be used for
shipping pharmaceuticals, or for long duration or high-value
shipments. For example, many pharmaceutical products such as
vaccines and antibodies must be maintained within a temperature
range of 2.degree. C. to 8.degree. C.
[0009] The high cost of shipping is at least partially related to
the volume occupied by the EPS insulation. For a one cubic foot box
with a 60 hour lifetime at 2.degree. C. to 8.degree. C., over 90
percent of the container volume is occupied by EPS and gel
packs.
[0010] Some reduction in volume and therefore shipping costs may be
obtained by using vacuum insulation panels (VIPs) as the thermally
insulating material. VIPs have a high thermal resistance; however,
they are much more costly than EPS sheets. Therefore, to be
economically competitive, VIPs should be provided in a manner that
the VIPs can be readily used multiple times.
[0011] When utilizing a container or similar article that is
insulated with VIPs, the highest potential for thermal losses from
the container occurs at the edges and corners where two VIPs are in
contact. Having an inadequate seal along these edges can severely
degrade the performance of the thermally-insulated container.
Sealing the edges of adjacent VIPs can be difficult since the
standard manufacturing method for VIPs involves evacuating the
panel and sealing one or more of the panel edges, which results in
a flap protruding from the edge. The presence of such a flap can
inhibit gap-free mating between adjacent panels.
[0012] U.S. Pat. No. 7,140,508 by Kuhn et al. discloses a shipping
box for shipping high-value objects such as framed paintings, where
the walls of the shipping box can be lined with VIPs. To avoid
thermal bridges and a decrease in performance, multiple layers of
VIPs can be used where the joints between adjacent VIPs in one
layer are offset relative to the joints in an underlying layer. It
is also disclosed that the edge flaps of the VIPs should not be
located in the area in which adjacent VIPs touch, such as along the
edge of the panel.
[0013] U.S. Pat. No. 6,244,458 by Frysinger et al. discloses VIPs
where the barrier film is provided as a sheet material with edges
that are sealed together. The edges are joined together over a
sealed portion that extends for 1/2 inch or more from the
underlying edge surface, such that the VIP does not have a smooth,
uniform outer profile. Accordingly, adjacent vacuum panels cannot
be positioned without space between them. Therefore, Frysinger et
al. provide a compressible layer of thermal insulation wrapped
around each of the VIPs. It is disclosed by Frysinger et al. that
the presence of the compressible insulation layer can reduce
thermal edge losses.
[0014] U.S. Pat. No. 6,220,473 by Lehman et al. discloses a
soft-sided collapsible insulative container having a base,
peripheral sidewalls extending from the base, and a lid. Each of
the base, lid and sidewalls are formed of a sealable pocket having
a compressible insulation lining. Each pocket is adapted to contain
a piece of block insulation to thermally insulate the container. A
flexible fabric casing extends tightly around the container in the
fully closed position to exert uniform pressure on the
container.
[0015] Standard insulation materials, including the compressible
insulation disclosed by Frysinger et al. and Lehman et al., do not
provide the thermal resistance of VIPs, and will inherently
contribute to thermal losses in a container that is otherwise lined
with VIPs. There remains a need for a thermally-insulated shipping
container system having improved thermal performance.
SUMMARY OF THE INVENTION
[0016] Accordingly, it is an object of the present invention to
provide a thermally insulative container insert that is adapted to
be placed within a container, such as a shipping container. The
insert can be placed within an outer container, such as a cardboard
box, to provide thermal insulation for a product placed within the
container. The insert can advantageously reduce the amount of
manual labor previously required to thermally insulate a container,
particularly when using vacuum insulation panels. The insert can
also minimize or eliminate the gaps that can exist between adjacent
insulation panels to increase thermal performance by reducing
thermal bridging and reducing the formation of condensation, or the
formation of ice in frozen applications. For dry ice shipments in
particular, ice can form within the container and increase the heat
load, serve as a thermal bridge and can push adjacent panels apart.
The present invention can reduce or eliminate the formation of ice
by providing a tightly sealed and thermally insulated product
cavity.
[0017] In one embodiment, a container insert for thermally
insulating a container is provided. The insert includes a base
insulation panel having a top surface, a bottom surface and a
peripheral edge surface. First and second side insulation panels
are provided each having a top surface, a bottom surface and a
peripheral edge surface. The side panels are attached to the base
panel in spaced-apart relation on opposite sides of the base panel
by a plastic backing sheet. First and second end insulation panels
are also provided each having a top surface, a bottom surface and a
peripheral edge surface. Each of the end panels is attached to the
base panel in spaced-apart relation on opposite ends of the base
panel by a plastic backing sheet. Each of the side panels and the
end panels can be pivoted upwardly toward the base panel to contact
the base panel along a seam and form side walls and end walls. The
plastic backing sheet covers at least a portion of each of the
seams between the base panel and the side panels and between the
base panel and the end panels to form an enclosure having a base,
side walls and end walls and a top opening.
[0018] In another embodiment, a container insert includes a base
insulation panel having an interior surface, an exterior surface
and a peripheral edge surface. First and second side insulation
panels are transversely disposed at opposite sides of the base
panel to form side walls, where each side panel has an interior
surface, an exterior surface and a peripheral edge surface. First
and second end insulation panels are transversely disposed at
opposite ends of the base panel to form end walls, each end panel
having interior surface, an exterior surface and a peripheral edge
surface. A plastic backing sheet is disposed around at least a
portion of the exterior surfaces of the base panel, side panels and
end panels. The plastic backing sheet covers at least a portion of
each of the seams between the base panel and the side panels and
between the base panel and the end panels, and covers at least a
portion of each of the seams between adjacent side panels and end
panels, such that the plastic backing sheet urges adjacent panels
together along the seams.
DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1(a) and 1(b) illustrate a thermal insulation panel
that is useful in the container insert of the present
invention.
[0020] FIG. 2 illustrates a top view of a container insert
according to an embodiment of the present invention.
[0021] FIG. 3 illustrates a top view of a container insert in a
partially-assembled state according to an embodiment of the present
invention.
[0022] FIG. 4 illustrates a top view of a container insert in a
partially-assembled state according to an embodiment of the present
invention.
[0023] FIG. 5 illustrates a top view of a container insert in an
assembled state according to an embodiment of the present
invention.
[0024] FIG. 6 illustrates a perspective view of a container insert
in an assembled state according to an embodiment of the present
invention.
[0025] FIGS. 7(a) and 7(b) illustrate cross-sectional views of
vacuum insulation panels according to an embodiment of the present
invention.
DESCRIPTION OF THE INVENTION
[0026] The present invention is directed to a container insert and
a method for using the container insert to thermally insulate
products contained therein. In this regard, the container insert
includes thermally insulative panels that form the walls of the
container insert.
[0027] FIGS. 1(a) and 1(b) illustrate a thermally insulative panel
that can be utilized in the container insert. The thermally
insulative panel 1 is preferably rigid such that the panel can form
a rigid wall of the container insert. The panel 1 includes a top
surface 2 and a mutually opposed bottom surface 6. The thermal
insulation panel also includes a peripheral edge surface 4
extending along the perimeter of the insulation panel 1. In one
embodiment, the peripheral edge surface 4 can have a thickness of
from about 1/4 inch to about 2 inches.
[0028] In one particularly preferred embodiment, the insulative
panel 1 is a vacuum insulation panel (VIP). In this regard, the
insulative panel 1 includes a thermally insulative core material 8
surrounded by a barrier film 9. The barrier film 9 is preferably a
polymer barrier film to facilitate heat welding of the panel 1 to a
plastic backing sheet, as is described below.
[0029] A container insert according to an embodiment of the present
invention is illustrated in FIGS. 2-5, which each illustrate a
top-view of the container insert 10 in various stages of assembly.
The insert 10 is illustrated in FIG. 2 in the fully flat and
unassembled configuration, before assembly by a user (e.g., a
shipper) and placement into an outer container, such as a cardboard
box. It is a significant advantage that the container insert 10 can
be shipped to a user in this flat configuration and assembled by
the user when needed to store or transport temperature sensitive
goods.
[0030] The insert 10 is adapted to be assembled and form a
thermally insulated bottom wall, side walls and end walls to define
a thermally insulated product cavity. The product can be inserted
through a top opening, and then a thermally insulated lid panel can
be placed over the top opening to provide a thermally insulated
product cavity.
[0031] Referring to FIG. 2, the insert 10 includes a base
insulation panel 12, a first side insulation panel 14, a second
side insulation panel 16, a first end insulation panel 18 and a
second end insulation panel 20. Although the various panels and
walls of the insert 10 are described as being disposed on the
bottom, side and end of the container insert, the insert can be
utilized in various orientations and such terms are not intended to
be limiting in this regard. For example, each of the insulation
panels could be a square panel of equivalent dimensions.
[0032] Each of the panels is thermally insulative panel, for
example a polyurethane panel, an expanded polystyrene panel or the
like. According to one embodiment, the thermally insulative panels
comprise vacuum insulation panels (VIPs). VIPs utilize the
insulative effects of a near-vacuum to provide a high thermal
resistance, and can provide such high thermal resistance at reduced
thicknesses as compared to conventional insulation, such as EPS,
thereby increasing the useful internal volume (e.g., the product
cavity) of a container lined with the insulative panels. VIPs are
disclosed in more detail below with respect to FIGS. 7(a) and
7(b).
[0033] According to the present invention, the insulation panels
are interconnected by a plastic backing sheet 26 that is attached
to the bottom surface of each insulation panel. For example, the
backing sheet can be heat welded to the bottom surface of each of
the insulation panels. The end panels and side panels are attached
to the plastic backing sheet 26 in spaced apart relation to the
base panel 12 in a manner that they can be pivoted upwardly toward
the base panel to form side walls and end walls of the container
insert. Although described herein as one contiguous plastic backing
sheet, the backing sheet can comprise two or more individual and
separate portions, so long as the backing sheet connects the base
panel to the side panels and end panels in the manner described
herein.
[0034] The plastic backing sheet 26 can perform several functions
in the assembled container insert 10, including covering and
sealing of the seams where adjacent insulation panels are in
contact and facilitating the compression of the adjacent panels
along the seams to reduce or eliminate gaps between adjacent
panels. In this regard, it should be noted that adjacent insulation
panels are in direct contact when the insert is assembled, as
opposed to having a material layer disposed therebetween. The
plastic backing sheet 26 is preferably vapor impermeable,
particularly with respect to water vapor to provide a condensation
barrier between the product cavity and the outside environment. The
plastic backing sheet 26 can also provide abrasion resistance to
the exterior surfaces of the container insert 10.
[0035] The plastic backing sheet 26 can comprise a single layer of
a plastic material, preferably a thermoplastic material such as
polyethylene (PE). More preferably, the plastic backing sheet 26 is
a multilaminate material comprising two or more layers of plastic
materials to provide multiple functionalities. For example, the
plastic backing sheet can comprise two layers of PE, with a layer
of a material disposed therebetween, such as a polyamide layer
(e.g., Nylon) or a polypropylene (PP) layer.
[0036] The end panels 18 and 20 are attached to the plastic backing
sheet 26 at opposite ends of the base panel 12. The end panels 18
and 20 are spaced-apart from the base panel 12 by a distance that
is approximately equal to the thickness of the base panel 12, with
a portion of the backing sheet 26 being disposed between the end
panels and the base panel 12, preferably along the entire edge of
each end panel that is adjacent to the base panel. In one
embodiment, the base panel 12 is a VIP having a thickness of at
least about 1/4 inch and up to about 2 inches, and therefore the
distance between the end panels and the base panel can also be from
about 1/4 inch to about 2 inches. In this manner, when the end
panels are pivoted upwardly and toward the base panel to form end
walls (FIG. 3), the portions of the backing sheet 26 disposed
between the base panel 12 and the end panels 18 and 20 forms a
tight seal along the bottom horizontal seams where the end panels
contact the base panel 12.
[0037] The plastic backing sheet 26 can also include linear
perforations 28a, 28b, 28c and 28d extending outwardly from the
opposed edges of the end panels 18 and 20 toward the base panel.
The backing sheet perforations facilitate the pivoting of the end
panels toward the base panel 12 to form end walls without moving
the side walls. The backing sheet perforations can be, for example,
scores in the sheet to enable the sheet to be easily separated, or
can be a cut directly through the sheet 26.
[0038] Side panels 14 and 16 are disposed on opposite sides of the
base panel 12 in spaced-apart relation to the base panel. As with
the end panels, a portion of the plastic backing sheet 26 is
disposed between the side panels and the base panel, preferably
along the entire edge of the panels that is adjacent to the base
panel. The spacing between the base panel 12 and the side panels 14
and 16 is preferably about equal to the thickness of the base panel
12 to facilitate the formation of a tight seal along the lower
seams of the side panels when they are pivoted upwardly toward the
base panel to form side walls.
[0039] As illustrated in FIG. 2, the insert 10 also includes means
to secure the backing sheet 26 around the exterior walls of the
container insert, that is, around the exterior surfaces (outside
the product cavity) of the end panels and side panels. In this
regard, the plastic backing sheet 26 extends beyond the opposed
side edges of the side panels 14 and 16. In this manner, when the
end panels are pivoted upwardly and the side panels are then
pivoted upwardly, that portion of the backing sheet extending
beyond the edges of the end panels can be wrapped around the
exterior surface of the panels and can be attached to the end
panels.
[0040] In the embodiment illustrated in FIG. 2, the attachment
means includes hook and loop fasteners having hook portions 22b and
24b attached to the plastic backing sheet 26, and loop portions 22a
and 24a attached to the bottom surface of the end panels.
[0041] FIG. 3 illustrates a top-view of the partially-assembled
container insert 10, namely where the end panels 18 and 20 have
been pivoted upwardly and toward the base panel 12 to form end
walls for the container insert 10. The portion of the backing sheet
26 disposed between the base panel 12 and the end panels 18 and 20
thereby forms a tight seal along the entire seam where the
peripheral edge surface of the end panels and the top surface of
the base panel are in direct contact. This advantageously reduces
the permeation of water vapor into the product cavity and hence
reduces condensation of water vapor when the interior product
cavity of the container insert 10 is at a reduced temperature.
[0042] FIG. 4 illustrates a top view of the partially assembled
container insert 10. Compared to FIG. 3, the side wall panels 14
and 16 have been pivoted upwardly and toward the base panel 10 to
form side walls for the container insert 10. As with the end
panels, the portion of the backing sheet 26 disposed between the
side panels and the base panel 12 forms a tight seal along the seam
where the base panel and side panels are in contact to reduce the
permeation of water vapor into the product cavity.
[0043] When the side panels are pivoted and placed on the base
panel 12 to form side walls, it can be seen that a portion of the
backing sheet 26 extends away from opposite ends of each side panel
and each such portion of the backing sheet 26 includes a hook
portion 22b/24b of a hook and loop fastener. In this regard, these
portions of the backing sheet can be pulled tightly and attached to
the back side of the end panels 18 and 20 which have loop portions
22a/24a adapted to attach to the hook portions 22b/24b. When the
backing sheet 26 is pulled tightly in this manner, the backing
sheet 26 urges the seams between the end panels and side panels
together to reduce or eliminate any gaps between the panels and
thereby improve the thermal performance of the container
insert.
[0044] Other means and methods of attaching the backing sheet 26 so
that it securely and tightly wraps around the periphery of the
insert 10 and secures the panels can be used. For example, the
backing sheet 26 can be attached by heat welding the backing sheet
to the external surface of the end panels, which can also include a
plastic material. However, temporary fasteners such as
hook-and-loop fasteners provide the advantage that the insert can
be easily disassembled and re-used.
[0045] A top view of an assembled container insert 10 is
illustrated in FIG. 5. It can be seen that the plastic backing
sheet 26 is wrapped tightly around the exterior of the side walls
and end walls and is attached to the end panels by hook and loop
fasteners 22 and 24. This provides at least two advantages--the
plastic sheet compresses the panel edges against each other to form
a tight seal along the vertical edges between panels, and the
plastic material of the backing sheet 26 provides a barrier to
prevent penetration of water vapor or other gases into the product
cavity defined by the insert. It will be appreciated that while the
backing sheet perforations 28 facilitate pivoting of the end panels
18 and 20 to form end walls (FIG. 2), such perforations should not
also be included with respect to the side panels, as this would
preclude the ability to tightly wrap the backing sheet 26 around
the periphery of the container insert 10. However, seams could
extend from the edges of the side panels, in lieu of those
illustrated in the figures extending from the end panels.
[0046] FIG. 6 illustrates a perspective view of an assembled
container insert 10. The insert 10 includes a base insulation panel
12 as well as side walls and end walls. The end walls are formed by
the first end insulation panel 18 and the second end insulation
panel 20. The end panels are transversely disposed on the base
panel at opposite ends of the base panel to form the end walls.
Similarly, the side walls are formed by a first side insulation
panel 14 and a second side insulation panel 16 which are also
transversely disposed on the base panel at opposite sides of the
base panel 12. By virtue of this assembly, horizontal seams exist
where the side panels and end panels contact the base panel and
vertical seams exist where the adjacent side panels and end panels
are in contact. For example, horizontal seams 13a and 13b are
formed between the base panel 12 and each of the side wall 16 and
the end wall 20. Similarly, vertical seams 20a and 20b form between
the end panel 20 and the two adjacent side panels 14 and 16. The
backing sheet 26 advantageously covers these seams and urges
(compresses) the panels together to reduce any gap between the
panels.
[0047] A lid 30 can be placed on the insert to seal the top
opening. The lid can include, for example, an insulation panel 32
of a size and type similar to the base panel 12. A piece of foam 34
such as polyethylene foam or a similar material can be placed on
top of the insulation panel 32 so that the bottom surface of the
insulation panel 32 is compressed against the top edge surfaces of
the side panels and end panels when the top lid of a container is
closed and pressed against the foam 34.
[0048] As is discussed above, the thermal insulation panels (e.g.,
panels 12, 14, 16, 18 and 20) can comprise vacuum insulation panels
(VIPs). Cross-sectional views of VIPs are illustrated in FIGS. 7(a)
and 7(b). Referring to FIG. 7(a), the VIP includes a core material
44a and a barrier film 42a disposed around the core material 44a.
During the manufacturing process, the core material 44a can be
pressed into the general shape of the panel (e.g., a rectangular
shape) which is placed into an envelope of the barrier material
42a. The barrier material envelope is then evacuated and sealed to
form a rigid VIP.
[0049] The core material provides structural strength to prevent
the panel walls from collapsing and to provide heat transfer
resistance, and a gas impermeable barrier film surrounding the core
material that is sealed after a near vacuum is achieved inside the
panel. The vacuum insulation panel is evacuated to a low pressure,
such not greater than about 100 mbar (about 75 torr), or less.
[0050] The core material can comprise a variety of materials, such
as open cell polyurethane or polystyrene foam (e.g., INSTILL,
available from the Dow Chemical Company). According to a preferred
embodiment, the core material is a particulate material, such as
silica, titania and/or carbon. The particulates can form a branched
network of primary particles which aggregate into larger particles.
Preferably, the core material has pore sizes ranging from about 10
nm to about 100 nm. The VIPs can also include getter or desiccants
within the panel that are adapted to adsorb residual gases and
moisture, which increases the useful lifetime of the panels.
[0051] The barrier film 42a is a substantially gas-impermeable
material that can be sealed at the edges to form an envelope for
the core material. The barrier film can be a laminate film that
includes a metallic layer and at least one plastic layer, such as a
laminate that includes a metallic layer sandwiched between two
plastic layers. However, barrier films that include a metallic
layer can be disadvantageous in the container insert since the
metallic layer can serve as a thermal bridge at the edges of the
insert, reducing the thermal performance of the insulation.
Further, metallized layers are subject to stress cracking, which
also can reduce thermal performance.
[0052] It is therefore preferred that the barrier film does not
include a metallized barrier. In this regard, the barrier film can
include a first plastic film layer, preferably a thermoplastic
layer, on the internal surface so that the inner layer of the
barrier film can be heat sealed after evacuation of the panel. It
is also preferred that the barrier film include an outer layer that
is also fabricated from a plastic material, such as PE, to enable
heat welding of the panels to the plastic backing sheet of the
container insert. According to one embodiment, the barrier film
comprises a multi-layer coextrudate which is not susceptible to
stress cracking. For example, the coextrudate can include a layer
of PE and a layer of ethylene vinyl alcohol (EvOH), with a layer of
a material such as polyamide (e.g., Nylon) or polyethylene
terephthalate (PET) disposed therebetween. The EVOH layer can
provide an oxygen barrier and the polyamide or PET can provide
toughness, e.g., abrasion resistance. Other layers could include
polyvinylidene chloride (PVDC) or a similar material for a moisture
barrier.
[0053] These plastic barrier film materials can be made, for
example, by coextrusion or lamination. Pigments can also be added
to one or more of the various layers for aesthetic purposes, i.e.,
so that the core material is not visible to the user. In this
regard, the plastic barrier film can also be comprised of different
colors to indicate different properties, such as the thickness of
the panel. The barrier film can have a thickness, for example, of
at least about 60 micrometers and not greater than about 200
micrometers.
[0054] Referring to FIG. 7(a), the sealing process to form the VIP
typically results in the formation of at least two flaps 46a and
48a along opposite edges of the panel 40a. Depending upon the
laminate materials used in the barrier film 42a and the desired
pressure within the panel, it may be desirable to have an extended
flap such as those illustrated in FIG. 7(a) to ensure that an
adequate seal is formed along the edges of the panel.
[0055] These flaps 46a and 48a can inhibit the formation of a tight
seal in insulated containers when that peripheral edge surface of
the panel presses against an adjacent panel. This has often
required the end-user to manually tape the flap down or take other
measures to ensure an adequate seal.
[0056] According to the present invention, the flap 46a/48a can be
bent and sealed to the surface of the panel. FIG. 7(a) illustrates
the flaps being pressed against the top surface of the panel 40a
and attached to the surface, such as by using heat and pressure. In
this regard, if the barrier material 42a has a plastic outer film,
the film can be heat treated under modest pressure to adhere the
flap to the surface of the panel.
[0057] FIG. 7(b) illustrates an alternative embodiment of a VIP
including a core material 44b wherein the flaps 46b/48b are shorter
than the flaps illustrated in FIG. 7(a) and are bent back and
attached to the peripheral edge surface of the panel 40b.
[0058] The container insert according to the present invention
advantageously provides thermally insulated side walls, end walls
and a thermally insulated base. After a product is placed into the
cavity defined by the side walls, end walls and base by inserting
the product through the top opening, a thermally insulated lid such
as a VIP panel can be placed over the opening to completely
surround the product with thermal insulation. The container insert
and lid can all be placed within an outer container, such as a
cardboard box, which is then sealed for storage or shipment of a
product. For example, the top lid can rest upon the top edges of
the side walls and end walls. A layer of a foam material, such as
polyethylene foam, can be placed on top of the lid (e.g., beneath
the outer cardboard lid) to provide uniform compression upon the
lid when sealed in the container to facilitate the formation of a
tight seal. In one embodiment, the lid can also be attached to the
backing sheet in a manner that the lid hinges and pulls down to
seal in a manner similar to the end panels and side panels.
[0059] While various embodiments of the present invention have been
described in detail, it is apparent that modifications and
adaptations of those embodiments will occur to those skilled in the
art. However, is to be expressly understood that such modifications
and adaptations are within the spirit and scope of the present
invention.
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