Note: Descriptions are shown in the official language in which they were submitted.
Thermal Container
Field of the Invention
The present invention relates to a thermal container which comprises at least
one flat back
cushion and a flat front cushion extending in a different plane above the back
cushion, said
cushions being connected to one another at opposite side edges as well as at a
further
side edge of the thermal container or being integrally formed or transitioning
into one an-
other via a connecting piece so that a cavity is formed between the back
cushion and the
front cushion, the back cushion and the front cushion each being formed from
at least one
bag or at least one compartment and a fibrous material located in the at least
one bag or
the at least one compartment.
Thermal containers of this type serve to maintain the temperature of a
packaged product
inserted into the cavity over a certain period of time. Such thermal
containers can thus be
used to maintain the cooling or heating of the packaged good inserted therein
over a cer-
tain time within a certain temperature window. It is thus possible to ship
frozen goods such
as frozen food or frozen animal feed for up to 36 hours by means of such
thermal contain-
ers without the particular food or feed being damaged.
Background of the Invention
In recent years, plastics have often been used to manufacture thermal
containers. This is
no longer justifiable from an ecological point of view. When natural
substances were used
to form thermal containers, the temperature duration was usually severely
limited.
Summary of the Invention
It is therefore the object of the present invention to provide a thermal
container which is
largely ecologically harmless, can be recycled and has an optimal temperature
mainte-
nance function.
This object is solved by a thermal container which comprises at least one flat
back cushion
and a flat front cushion extending in a different plane above the back
cushion, said
Date Recue/Date Received 2020-07-10
2
cushions being connected to one another at opposite side edges as well as at a
further
side edge of the thermal container or being integrally formed or transitioning
into one an-
other via a connecting piece so that a cavity is formed between the back
cushion and the
front cushion, the back cushion and the front cushion each being formed from
at least one
bag or at least one compartment and a fibrous material located in the at least
one bag or
the at least one compartment in which the fibrous material is an individual
layer or a stack
of a plurality of individual layers lying on top of each other, which is made
from creped
and/or corrugated and/or zigzag-shaped laid or folded fibrous material,
wherein each of
the individual layers comprises a crepe height or a corrugated and/or zigzag
height of
0.3 and/or the fibrous material comprises fibrous flakes or fibrous powder,
which is applied
to a flat supporting element being made from fibrous material or inserted
between two flat
supporting elements made from fibrous material.
Both cold and warm objects can be stored and transported in the thermal
container ac-
cording to the invention. The thermal container according to the invention is
particularly
suitable as a cooler bag. The at least one object, the temperature of which is
to be main-
tained, can advantageously be inserted into the cavity formed between the back
cushion
and the front cushion connected thereto. The cavity can then be closed
appropriately.
The fibrous material of the back cushion and the front cushion guarantees a
particularly
advantageous thermal insulation of the at least one object inserted into the
thermal con-
tainer from the surroundings. The structure of the fibrous material has a
large number of
air pockets or air gaps, as a result of which the respective temperature can
be maintained
particularly well. It is, for example, even possible with the present
invention to maintain the
cooling of a packaged product inserted into the thermal container in a desired
temperature
window for up to 72 hours.
On the one hand, the air pockets or air gaps are formed between the
corrugations and/or
folds of the individual layer and, on the other hand, between the individual
layers that lie
flat above each other and that are formed from creped and/or corrugated and/or
zigzag-
shaped laid or folded fibrous material. Due to the corrugation, zigzag-shaped
laying or
folding and/or creping of these individual layers, each of the individual
layers has a large
number of mountains and valleys with air collecting in the valleys. Since the
corrugation
and/or zigzag-shaped laying or folding and/or creping is never identical from
one individual
layer to the next, and the individual layers are not stacked on top of one
another or pressed
Date Recue/Date Received 2020-07-10
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into one another in a form-fit manner, the valleys of the individual layer
above a layer do
not or do not completely fit into the valleys of the individual layer below a
given layer so
that and air cap is maintained in any case.
The special feature of the present invention is that each of the individual
layers has a crepe
height or a corrugated and/or zigzag height of 0.3 mm, preferably 0.4 mm,
particularly
preferably 0.6 mm, in one embodiment of 0.65 mm. The creped variant is so-
called high
creping. This ensures that particularly large air pockets or air gaps are
formed between
corrugated and/or folded and/or creped fibrous material between the individual
layers lying
one above the other, which leads to a particularly high temperature stability
of the thermal
container formed by these.
The same effect is achieved if the fibrous material has fibrous flakes or
fibrous powder
which is applied to a flat supporting element made from fibrous material or
inserted be-
tween two flat supporting elements made from fibrous material. There is a lot
of air between
the fibrous flakes or the particles of the fibrous powder, which serves for
thermal insulation.
Both variants have in common that the respective fibrous material does not
slip, on the
one hand, due to the corrugated and/or folded and/or creped individual layer
or the plurality
of individual layers lying on top of one another and, on the other hand, due
to the use of at
least one flat supporting element and its respective insertion into the bag or
the compart-
ment. The bag or the compartment form a sleeve for the respective fibrous
material, which
leads to a mechanical stabilization.
In the present invention, a number of at least 10 individual layers,
preferably 24, 28 or 32
individual layers, is preferably used as a plurality of individual layers
lying one above the
other. These individual layers are doubled and cut to the desired width
depending on the
size of the cushion.
The bag or compartment also has a protective function for the fibrous material
located
therein. Furthermore, it is, for example, possible to insert at least one cold
pack into the
bag or the compartment.
Another advantage of the fibrous material used, which may be a primary fibrous
material
such as a cellulose, a wood pulp or a semi-pulp and/or a secondary fibrous
material such
Date Recue/Date Received 2020-07-10
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as fibrous material obtained from recovered paper, is that it is a natural
material which is
harmless to the environment, easy to recycle and already has low heat
conduction and
thus good thermal insulation properties.
In addition, the formation of the fibrous material used leads to an
advantageous softness
and bulkiness, which ensures that the packaged good can be safely stored and
transported
in the thermal container.
The thermal container, according to the invention, is easy to stack but can
also be used
as a shopping bag.
The individual layers of the creped fibrous material preferably have a creping
factor of at
least 40%, in a special embodiment 44%. The latter creping factor corresponds
to an elon-
gation of 80%.
In a variant of the present invention, the fibrous flakes or the fibrous
powder with at least
one binder is applied to the flat supporting element formed from fibrous
material or inserted
between the two flat, fibrous supporting elements. By means of the
additionally provided
binder, the fibrous flakes or the fibrous powder, which can be sprayed, for
example, onto
a supporting element or between the two supporting elements, can be fixed well
at their
respective position on the supporting element or between the supporting
elements.
It is particularly favorable if the flat supporting element or supporting
elements are made
from paper. On the one hand paper is easily recyclable, and on the other hand
it creates
a stable yet flexible support for the fibrous flakes or the fibrous powder.
If the at least one bag in the present invention is formed from a fleece made
of thermo-
plastic material, it offers good moisture protection for the fibrous material
therein, which
has good absorbency. This is particularly the case if the fleece is a
polypropylene spun-
bonded.
For this purpose, it is particularly advantageous if the at least one bag
encompasses the
fibrous material like a tube.
Date Recue/Date Received 2020-07-10
5
In another, likewise advantageous embodiment of the present invention, the at
least one
bag or the at least one compartment of the back cushion as well as the at
least one bag
or the at least one compartment of the front cushion are made from paper,
preferably from
kraft paper. As a result, the entire thermal container consists of
ecologically recyclable
material, namely paper and fibrous material.
Holes can be made in the fleece and/or the paper of which the bag, the front
cushion
and/or the back cushion or the compartment are formed. For example, air holes
can be
formed in the paper with a spiked roller, as a result of which the formation
of stagnant
water in the thermal container can be avoided.
In a preferred embodiment of the invention, this can be achieved in that the
at least one
bag or the at least one compartment of the back cushion as well as the at
least one bag
or the at least one compartment of the front cushion are formed by an inner
paper bag
inserted in an outer paper bag, wherein the fibrous material is located each
time between
an outer side of the inner paper bag and an inner side of the outer paper bag.
The inner
paper bag is thus inserted into the outer paper bag, and the fibrous material
is inserted
between the material of the inner paper bag and the material of the outer
paper bag at
least on the front side and the back side of this embodiment of the thermal
container ac-
cording to the invention. The respectively packaged good, which is typically
to be kept
cool, can then be placed into the inner paper bag.
In an expedient configuration of this embodiment of the invention, the inner
paper bag and
the outer paper bag having fibrous material are connected to one another. As a
result, the
inner fibrous material cannot slide out of the space between the outer paper
bag and the
inner paper bag. This also means that there is no risk that the packaged good
slides into
the space between the outer paper bag and the inner paper bag.
The thermal container, according to the invention, is particularly
ecologically valuable if the
creped fibrous material is made from cellulose wadding, which is made from at
least 90%
recycled waste paper with waste paper qualities in accordance with DIN EN 643.
It is possible to prevent the fibrous material from sliding within the bag or
compartment if
the at least one bag or the at least one compartment is fastened to the
fibrous material
with adhesive lines that are spaced apart from one another. Synthetic hot melt
can be used
Date Recue/Date Received 2020-07-10
6
as an adhesive, for example. This adhesive can be applied in thin lines, for
example at a
distance of 15 to 30 mm, preferably 20 mm.
In order to be able to maintain the temperature of a packaged good in the
thermal con-
tainer, it is advisable to close the thermal container appropriately. This can
be realized
particularly well if either the back cushion has a back cushion section
protruding on one
side over the front cushion or if a closure flap is connected to the back
cushion on one
side, wherein the protruding back cushion section or the closure flap is
foldable onto a
surface of the front cushion and connectable with said cushion either directly
or indirectly
so as to close the cavity of the thermal container.
The protruding back cushion section or the closing flap are preferably made
from the same
material as the material of the at least one bag.
In order to achieve this, the at least one bag with the fibrous material
inserted therein is
preferably separated from a bag web having a plurality of such bags, and the
protruding
back cushion section or the closure flap is formed from fleece made from
thermoplastic
material which protrudes from a bag section containing the fibrous material.
The thermal container according to the invention can be used particularly well
as a cooler
bag if at least one carrying handle and/or at least one closing means for
closing the cavity
is provided on the thermal container.
The side edges of the thermal container, according to the invention, are
particularly sturdy
if the back cushion and the front cushion are sewn and/or glued and/or
squeezed together
on the opposite side edges of the thermal container.
Brief Description of the Drawings
Preferred embodiments of the present invention are explained in more detail
below with
reference to figures, wherein
Figure 1
schematically shows a possible embodiment of a thermal container accord-
ing to the invention in a top view;
Date Recue/Date Received 2020-07-10
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Figure 2 schematically shows an embodiment of the thermal container
according to
the invention with a packaged good inserted in a top view;
Figure 3 schematically shows a possible embodiment of a back or front
cushion of an
embodiment of the thermal container according to the invention in a side
view;
Figure 4 schematically shows a further embodiment of a back or front
cushion of a
further embodiment of the thermal container according to the invention in a
side view;
Figure 5 schematically shows another embodiment of the thermal container
accord-
ing to the invention in a perspective side view; and
Figure 6 schematically shows a device for forming an embodiment of the
thermal con-
tainer according to the invention.
The represented embodiments are not shown to scale in any of the figures.
Rather, for the
sake of clarity, certain features are shown particularly large in the figures
in comparison to
other features of the invention. Most of the hidden features are shown with
dashed lines.
Detailed Description
Figure 1 schematically shows a possible embodiment of a thermal container 1
according
to the invention from a top view. In the exemplary embodiment shown, the
thermal con-
tainer 1 is a cooler bag for transport purposes. Such a cooler bag can have,
for example,
an outer width from 300 to 600 mm and an outer length from 300 to 600 mm. The
closure
flap of the cooler bag can have a length from 50 to 120 mm. Other dimensions
are also
possible, of course.
The thermal container 1 can, however, also be used to keep objects warm.
In Figure 2, the thermal container 1 from Figure 1 is shown from a top view.
It is opened
and a packaged good 15 is inserted therein.
Date Recue/Date Received 2020-07-10
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The thermal container 1 has a flat back cushion 2 and a flat front cushion 3.
The back
cushion 2 is connected to the front cushion 3 on the opposite side edges 4, 5
of the thermal
container 1. In the exemplary embodiment shown, this connection is realized by
seams
16, 17 running along the side edges 4, 5.
In other embodiments of the invention, which are not shown, this connection
can be made
alone or in combination with the seams 16, 17 by gluing and/or squeezing the
material.
In the exemplary embodiment shown in Figs. 1 and 2, the back cushion 2 and the
front
cushion 3 are formed from the same material web in the form of a bag web.
Therefore, the
back cushion 2 is formed in one piece with the front cushion 3 on a further
side edge 6 of
the thermal container 1, which means that the material of the back cushion 2
therefore
transitions directly to the material of the front cushion 3 on the side edge
6, which can form
a bottom edge of the bag, for example.
In other embodiments of the present invention that are not shown, the back
cushion 2 and
the front cushion 3 can also be formed separately and connected to one another
at the
side edge 6. Furthermore, it is possible that, in other embodiments of the
present invention,
at least one piece of material is provided between the back cushion 2 and the
front cushion
3 and connected to the side edges 4, 5 and/or 6. The piece of material can,
for example,
be strip-like or web-like.
A cavity 7 is formed between the back cushion 2 and the front cushion 3, into
which the
packaged good 15 is inserted, as can be seen in Figure 2.
In the embodiment shown in Figs. 1 and 2, the back cushion 2 has a back
cushion section
21 protruding from the front cushion 3 on one side. In other embodiments of
the present
invention, a closure flap can also be connected to one side to the back
cushion 2. The
protruding back cushion section 21 or the closure flap, as indicated
schematically by the
arrow A in Fig. 2, is folded onto a surface of the front cushion 3 to close
the cavity 7 and
is connected directly or indirectly to it. The protruding back cushion section
21 or the clo-
sure flap can, for example, be glued to the front cushion 3 by means of
adhesive lines.
Adhesive tufts may be used for this as well.
Date Recue/Date Received 2020-07-10
9
The back cushion 2 and the front cushion 3 each comprise a bag 8. The bag
encloses a
fibrous material 9 like a tube. As can be seen in Figure 5, at least one
compartment 18
may be provided instead of the bag 8 in which the fibrous material 9 is
located. Compared
to the bag 8, the compartment 18 is not completely formed around the fibrous
material 9
but can be closed in advantageous variants of the invention.
In the thermal container 1 shown in Figures 1 and 2, the fibrous material 9 is
used, which
is shown schematically in Figure 3 in a side view that is not to scale.
The fibrous material 9 consists of a stack of a plurality of individual layers
91 made from
creped fibrous material lying flat one above the other. In other embodiments
of the inven-
tion, a corrugated and/or zigzag laid or folded fibrous material can be used
instead of the
creped fibrous material. What is special about the creped fibrous material
used here is that
it is so-called high creping. The creped fibrous material used therefore has a
particularly
high crepe height d of 0.3 mm per individual layer 91. In advantageous
embodiments of
the present invention, the crepe height d is even greater, for example > 0.5
mm or even >
0.65 mm.
In the material used, which is cellulose wadding in the exemplary embodiment
shown, the
crepe height d of 0.65 mm leads to an elongation of 80% which in turn
corresponds to a
crepe factor of 44%.
In the exemplary embodiment shown, the mass per unit area of the creped
fibrous material
used is 23 grams per square meter.
In the exemplary embodiment shown, the creped fibrous material was produced in
the
following way:
The base material that was used is recycled cellulose wadding from selected
waste paper
qualities in accordance with DIN EN 643.
After a wet pulping process and removal of non-paper components, but without
additional
bleaching, the recycled cellulose wadding was creped out on a Yankee cylinder
by means
of a ceramic-coated steel scraper.
Date Recue/Date Received 2020-07-10
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In order to achieve the high crepe height d and thus a high volume of the
stack formed
from the individual layers 91, the adhesion of the cellulose fibers to the
cylinder surface,
the geometry of the scraper as well as the angle of attack of the scraper and
the draft angle
of the creped cellulose wadding web are specifically adjusted. The elongation
or the crepe
factor is produced accordingly by the difference in speed between the Yankee
cylinder and
the reel-up.
After the creping, the individual layers 91 are doubled, for example to form a
stack with 24,
28 or 32 individual layers 91. This is preferably done on a laying machine.
The individual
layers 91 typically lie one above another in the same layer generation
direction. However,
since the creping never lies exactly one above the other, the stacking of the
individual
layers 91 results in a correspondingly high stack height and at the same time
a high stack
volume. The stack height can, for example, be about 15 mm for 24 individual
layers 91,
about 20 mm for 28 individual layers 91 and about 25 mm for 32 individual
layers 91. In
principle, however, it is also conceivable to place the individual layers one
above the other
with an alternating alignment so that the creping varies from individual layer
91 to the next
individual layer 91 or so that the creping varies from a plurality of
individual layers 91 in-
tersects with individual or a plurality of individual layers 91.
After that, the stack produced is cut into the desired width depending on the
size of the
back cushion 2 and the front cushion 3.
Subsequently, the cellulose wadding layers are enclosed with the bag 8.
In the exemplary embodiment shown in Figures 1, 2 and 3, the bag 8 consists of
a poly-
propylene spunbond with which the stack of the individual layers 91 is
enclosed in a tube-
like manner. The polypropylene spunbond ensures on the one hand the cohesion
of the
individual layers 91 and on the other hand provides moisture protection, for
example
against condensation.
The bag 8 is fastened to the creped fibrous material 9, as shown schematically
in Figure
1 by means of lines 13 of hotmelt adhesive placed at a distance from one
another. These
lines may, for example, be approximately 20 mm apart and run along the
material web
from which the back cushion 2 and the front cushion 3 are formed.
Date Recue/Date Received 2020-07-10
11
It is advantageous if this material web has areas filled with the fibrous
material 9 and ad-
joining pure fleece areas. Then, a fleece area, which adjoins a back cushion
section of the
material band, can be used as a closing flap for closing the thermal container
1. A fleece
protrusion over the areas filled with the fibrous material 9 can, for example,
be approxi-
mately 50 mm.
In order to form the back cushion 2 and the front cushion 3 from the material
web, the latter
is cut transversely to its web running direction.
Subsequently, a section of the area of the separated material web piece filled
with the
fibrous material, which later forms the front cushion 3, is folded over the
rest of this material
web piece that forms the back cushion. Then, the side edges 4, 5 are sewn
and/or glued
and/or squeezed together. The squeezing is preferably carried out by means of
gears. The
gluing can be dispensed with.
Instead of the fibrous material 9 shown schematically in Figure 3, the fibrous
material 9'
shown schematically in Figure 4 in a side view that is not to scale can also
be used in the
above-described and further embodiments of the invention.
The fibrous material 9' is also located in a bag 8, which may be designed as
described
above.
The fibrous material 9' comprises fibrous flakes 92 or fibrous powder which is
applied to a
flat supporting element 93 made from fibrous material or, as shown in Figure
4, inserted
between two flat supporting elements 93, 94 made from fibrous material. The
fibrous flakes
are preferably pulp flakes, and the fibrous powder is preferably pulp powder.
A binder can be applied to the supporting element 93 or inserted between the
two support-
ing elements 93, 94 with the fibrous flakes 92 or the fibrous powder.
In the exemplary embodiment shown, the flat supporting elements 93, 94 are
formed from
paper.
Figure 5 schematically shows another embodiment of a thermal container 1',
according to
the invention, in a perspective side view.
Date Recue/Date Received 2020-07-10
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The thermal container 1' comprises an outer paper bag 11 and an inner paper
bag 12
located in the outer paper bag. Fibrous material 9, which is constructed as
described
above, is inserted between the inner paper bag 12 and the outer paper bag 11
on at least
two opposite sides of the thermal container. The fibrous material 9' described
above may
also be used instead of the fibrous material 9 or in addition to the fibrous
material 9.
The inner paper bag 12 and the outer paper bag 11, which includes the
respective fibrous
material 9, 9' may be connected to one another.
Carrying handles 14 are provided on an upper side of the thermal container 1'.
Suitable closure means may also be provided on the thermal container 1'.
As shown, the thermal container 1' may have a block bottom 19 but may also be
designed
without the block bottom 19.
Figure 6 schematically shows a device 10 for forming an embodiment of the
thermal con-
tainer 1, 1' according to the invention, in which the fibrous material 9 is
corrugated and/or
laid in a zigzag-shaped shape or folded.
In the exemplary embodiment shown in Figure 6, the corrugated and/or zigzag-
shaped laid
or folded fibrous material 9 was produced in the following way but can also be
produced
in other or modified ways in other embodiments of the invention:
Pulp, preferably creped or uncreped tissue, for example recycled cellulose
wadding made
from selected waste paper qualities in accordance with DIN EN 643, was used as
the
fibrous material 9. The pulp used preferably, but not necessarily, has a
grammage below
20 g/m2.
A wet pulping process and removal of non-paper components, but without
additional
bleaching, may have been carried out on the fibrous material 9, but these
steps are op-
tional. The corrugation or zigzag-shaped folding of the fibrous material 9 was
then carried
out in accordance with the following procedure:
Date Recue/Date Received 2020-07-10
13
As can be seen in Figure 6, the fibrous material 9 in the form of a layer of
pulp is unrolled
from a pulp roll 22 on a device 10 with an unrolling speed v1. Then the
fibrous material 9
is guided, for example, through a gap in a pair of rollers between two counter-
rotating
transport rollers 23, 24. The rotational speed of the transport rollers 23, 24
can be set
separately from one another. After having passed through the pair of rollers
23, 24, the
fibrous material 9 is withdrawn at a withdrawal speed v2, that is to say it is
transported
further.
In the embodiment shown, the fibrous material 9 is fed to the pair of rollers
23, 24 on a
straight path. In other embodiments of the invention, which are not shown, the
fibrous
material 9 may also be supplied in such a way to the pair of rollers 23, 24
that corrugations
and/or folds are specifically generated in the fibrous material 9 upstream
from the pair of
rollers 23, 24.
The withdrawal speed v2 is set so that it is lower than the unrolling speed
vi. As a result,
the fibrous material 9 jams and forms folds and/or corrugations 90 over the
further course
of the device 10. The withdrawal speed v2 and/or the unrolling speed vi may
also be varied
in the course of the method.
Furthermore, paper layers 81, 82 are fed to the device 10 on both sides of the
fibrous
material 9. The paper layers 81, 82 are preferably made from kraft paper.
Between further
transport rollers 25, 26, 27, 28 of the device 10, a first of the paper layers
81 is guided over
the folded and/or corrugated fibrous material 9, and a second of the paper
layers 82 is
guided under the folded and/or corrugated fibrous material 9.
The feed speed of the paper layers 81, 82 preferably corresponds to the
withdrawal speed
V2 and is therefore also less than the unrolling speed vi.
Due to the folds and/or corrugations 90, the fibrous material 9 located
between the paper
layers 81, 82 encloses air. These air pockets create an insulating effect.
In other embodiments of the present invention, which are not shown, a
plurality of individ-
ual layers 91 of corrugated and/or folded fibrous material 9 can be produced,
which are
then placed one above the other and only then are the paper layers 81, 82
guided above
or below the individual layers 91 of corrugated and/or folded fibrous material
9.
Date Recue/Date Received 2020-07-10
