U.S. patent application number 11/962756 was filed with the patent office on 2009-06-25 for flexible film plate-mat bag.
Invention is credited to Eric Henderson, John Michels, Joe Sagel.
Application Number | 20090161995 11/962756 |
Document ID | / |
Family ID | 40788741 |
Filed Date | 2009-06-25 |
United States Patent
Application |
20090161995 |
Kind Code |
A1 |
Henderson; Eric ; et
al. |
June 25, 2009 |
FLEXIBLE FILM PLATE-MAT BAG
Abstract
A method for forming a plate-mat bag using a form, fill, and
seal machine and the resultant bag. The film used to form the bag
is oriented so that the product side layer is not a critical
barrier layer. The top most portion of the bag is unsealed forming
a tab. Below the top most portion, a peelable upper seal is
utilized so that a consumer can destroy the upper seal using the
tab and tear open the bag along slits made in the product side
layer. This results in an easy open package which when opened can
serve as a plate.
Inventors: |
Henderson; Eric; (Dallas,
TX) ; Michels; John; (Highland Village, TX) ;
Sagel; Joe; (Plano, TX) |
Correspondence
Address: |
CARSTENS & CAHOON, LLP
P O BOX 802334
DALLAS
TX
75380
US
|
Family ID: |
40788741 |
Appl. No.: |
11/962756 |
Filed: |
December 21, 2007 |
Current U.S.
Class: |
383/210 ;
383/207; 53/459; 53/469 |
Current CPC
Class: |
B65B 61/02 20130101;
B65B 61/18 20130101; B65D 75/5855 20130101; B65B 9/20 20130101;
B65D 75/5833 20130101 |
Class at
Publication: |
383/210 ;
383/207; 53/459; 53/469 |
International
Class: |
B65D 33/16 20060101
B65D033/16; B65D 65/26 20060101 B65D065/26; B65B 43/26 20060101
B65B043/26; B65B 1/04 20060101 B65B001/04 |
Claims
1. A package comprising a flexible film, said package comprising: a
bottom seal; an upper peelable seal comprising a force distributing
configuration, wherein said upper peelable seal has a seal area of
a defined width and length; a front panel defined as between said
bottom and upper seals, wherein said front panel has a right side
and a left side; a back panel contiguous with said front panel and
defined as between said bottom and upper seal; wherein said front
and back panels each comprise at least two layers of film, an inner
and an outer layer; wherein said inner layer comprises at least two
score lines running from the upper seal and the bottom seal; and
wherein said package comprises an extension of the package film
above the upper seal.
2. The package of claim 1 wherein said outer layer comprises
oriented film.
3. The package of claim 2 wherein said orientation is aligned with
said score lines.
4. The package of claim 1 wherein said outer layer comprises
barrier properties.
5. The package of claim 4 wherein said outer layer comprises a
metalized film.
6. The package of claim 1 wherein said upper seal comprises a tip,
and wherein the seal area at said tip is narrower than the width of
the seal area along the rest of said seal.
7. The package of claim 1 wherein the seal area of said upper seal
has a width of between about 1/16.sup.th to about 1/8.sup.th of an
inch.
8. The package of claim 1 wherein said upper seal comprises a
chevron shaped seal.
9. The package of claim 1 wherein said extension of the package
film above the upper seal further comprises two cuts in said front
panel thereby forming a tear tab.
10. The package of claim 1 wherein said at least two score lines
comprise at least one score line vertically oriented on a left side
of said front panel, and wherein at least two score lines further
comprise at least one score line vertically oriented on a right
side of said front panel.
11. The package of claim 1 wherein said upper peelable seal
comprises resin.
12. The package of claim 1 wherein said upper peelable seal
comprises a cold seal.
13. The package of claim 1 wherein said upper peelable seal
comprises a line seal.
14. A method for making a flexible film package said method
comprising the steps of: a) obtaining a flexible film web having a
layer comprising at least two vertical score lines, wherein at
least one layer within said flexible film is oriented to
preferentially tear in the direction of said at least two score
lines; b) feeding said flexible film into a form, fill, and seal
machine such that said at least two score lines are parallel to the
direction of film travel; c) forming said flexible film web into a
tube; d) sealing said flexible film web at the bottom of said tube,
thereby forming a bottom seal on a resultant package; e) filling
said resultant package with product; and f) sealing at the top of a
resultant package a force distributing peelable seal wherein film
material extends beyond said seal, and wherein said seal has a seal
area of a defined width and length.
15. The method of claim 14 further comprising the step of: g)
cutting said film material extending beyond said seal to form a
tear tab.
16. The method of claim 14 wherein said sealing step f) comprises
sealing at the top of a resultant package a chevron shaped
seal.
17. The method of claim 14 wherein said sealing step f) comprises
sealing at the top of a resultant package a seal, wherein the seal
area of said seal has a width of between about 1/16.sup.th to about
1/8.sup.th of an inch.
18. The method of claim 14 wherein said sealing step f) comprises
sealing at the top of a resultant package a seal, wherein said seal
comprises a tip, and wherein the seal area at said tip is narrower
than the width of the seal area along the rest of said seal.
19. The method of claim 14 wherein said obtaining step a) comprises
obtaining a layer of oriented polypropylene.
20. The method of claim 14 wherein said filling step e) comprises
filling said resultant package with a snack food.
21. The method of claim 14 wherein said feeding step b) comprises
feeding said flexible film into a vertical form, fill, and seal
machine.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to an easy to open package,
designed in a plate-mat bag configuration, and a method for making
same. When the package of the present invention is opened it forms
a plate which the consumer can set on a surface and consume the
packaged contents. Several features of one end of the package
provide for easy opening of the package by a consumer.
[0003] 2. Description of Related Art
[0004] Snack foods and other items are often packaged in bags
formed from thin, flexible packaging films. These thin films are
formed primarily of plastics, such as polypropylene and
polyethylene, but can also contain metalized films, foil, paper, or
oriented films. These packaging films can have numerous layers
directed to achieving specific needs, but are generally formed at
least in part by extrusion of a plastic layer, co-extrusion of
multiple layers simultaneously, extrusion coating of another
material (such as paper), and the lamination of two layers together
via either extrusion lamination or adhesive lamination. In the
discussions below, both extrusion lamination and adhesive
lamination processes are discussed in more detail, but it is noted
that any designated layer that is fed into these two processes can
already be a multi-layer film formed by any of the above
processes.
[0005] An exemplary film 100 for packaging of food products is seen
in FIG. 1. The outermost layer 102 is an OPP layer, short for
oriented polypropylene, while the innermost layer 106 is a
metalized OPP or other barrier material. An oriented polymer
material has been specially treated so that the long polymeric
molecules tend to align in a given direction, causing the material
to preferentially tear in that direction. Sandwiched between the
two OPP layers 102, 106 is an adhesive such as polyethylene 104 or
other adhesive. Printing for the package is done on the inside of
the outer layer and becomes sandwiched between the middle and outer
layers. The innermost, metallic layer 106 can itself be a layered
laminate and contains a sealant layer 108 on what will be the
inside, or product side, of the package. This sealant layer 108 is
typically formed of a ter-polymer, composed of ethylene, propylene,
and butylenes, along with the metallic layers, and provides a
barrier to retain taste and freshness of the product contained
therein. Other materials used in packaging are polyester, paper,
polyolefin extrusions, adhesive laminates, and other such
materials, or a layered combination of the above.
[0006] Once the material is formed and cut into desired widths, it
can be loaded into a vertical form, fill, and seal machine to be
used in packaging the many products that are packaged using this
method. FIG. 2 shows an exemplary vertical form, fill, and seal
machine that can be used to package snack foods, such as chips.
This drawing is simplified, and does not show the cabinet and
support structures that typically surround such a machine, but it
demonstrates the working of the machine well. Packaging film 210 is
taken from a roll 212 of film and passed through tensioners 214
that keep it taut. The film then passes over a former 216 which
directs the film as it forms a vertical tube around a product
delivery cylinder 218. This product delivery cylinder 218 normally
has either a round or a somewhat oval cross-section. As the tube of
packaging material is pulled downward by drive belts 220, the edges
of the film are sealed along its length by a vertical sealer 222,
forming a back seal 224. The machine then applies a pair of
heat-sealing jaws 226 and accompanying jaw face 233 against the
tube to form a transverse seal 228. Different shapes of jaw faces
233 result in different shaped seals. The transverse seal 228 acts
as the top seal on the bag 230 below the sealing jaws 226 and the
bottom seal on the bag 232 being filled and formed above the jaws
226. After the transverse seal 228 has been formed, a cut is made
across the sealed area to separate the finished bag 230 below the
seal 228 from the partially completed bag 232 above the seal. The
film tube is then pushed downward to draw out another package
length. Before the sealing jaws form each transverse seal, the
product to be packaged is dropped through the product delivery
cylinder 218 and is held within the tube above the transverse seal
228.
[0007] The form, fill, and seal machines are quite expensive, in
the range of $250,000 each, but pay for themselves easily when
compared to the cost of pre-formed bags and the machinery to fill
them. However, in order to maximize the productivity of the form,
fill, and seal machines, it is common for the product delivery tube
218 and former 216 to be made as a unit that is easily
interchangeable, so that different size packages can be made by the
same machine. The length of the transverse seal can also be
changed, by exchanging the sealing jaws 226, or in some cases,
merely by exchanging their facings (the portion of the sealing jaws
which actually makes contact with the packaging film). By changing
these elements, as well as the width of film roll feeding into the
machine and the programming of the machine, one form, fill, and
seal machine can handle a number of different products in different
size packages, limited primarily by the width of film the machine
will handle, the maximum length of bag the machine is designed to
handle, and the available former/delivery tube assemblies.
[0008] Although there is no one perfect package for all uses, there
are a number of desirable features that manufacturers strive for in
packages made on a vertical form, fill, and seal machine. One such
feature is the ability to easily open the package. Consumers now
must grip and open the package, usually with a thumb and one or
several fingers on both hands. The thumb and fingers must pinch and
tear with sufficient force to break the seal. This can become more
difficult as a consumer gets older. For example, some consumers
have arthritis or have lost strength in their hands. Grasping the
sides of a flexible bag and opening it as previously described may
be a difficult task for them. Therefore, it is desirable to have a
bag that is easier to open by hand than is available from the prior
art. There have been some attempts at this to include an easy open
package containing, for example a tear notch and perforations that
allow for easier opening. However, even these traditional pillow
containers have a downside in that when opened the package falls on
its side and consequently must be balanced to keep product from
spilling. Thus, it is desirable to have a package that does not
need to be balanced for fear of spillage. New stand-up packages
have been developed that ease the balancing problem such as the
package disclosed by commonly owned U.S. Pat. No. 6,722,106 to
Bartel et al. However, these vertical stand-up packages still only
offer a small cross-sectional area from which product can be
retrieved. Many consumers prefer the ease of eating snacks from a
plate or a bowl that offers a relatively large surface area for
product retrieval rather than a package wherein a consumer's hand
must be inserted into the package to retrieve a food product. Thus,
it is also desirable to have a package that offers maximum surface
area from which product can be retrieved. Consequently, it is
desirable to have an easy to open package that upon opening
functions as a "plate-mat" which holds food product. The word
"plate-mat" comes from combining plate and placemat, and means a
container that is generally horizontal when opened such that it can
be eaten from like a plate. A feature of the container can also be
used as a placemat once the container is open. Finally, because of
the speed and productivity achieved on a vertical form, fill, and
seal machine, it is desirable that any such package alteration be
capable of being produced on such a machine.
SUMMARY OF THE INVENTION
[0009] A flexible easy to open package that also serves as a plate
for storing and eating food and method for making same is provided.
The package comprises two seals: a lower seal and an upper peelable
seal. The upper seal has geometry so that as the seal is pulled
downward, the force gets distributed downward and outward. There is
a portion of unsealed film above the upper seal which forms a tab.
This allows a consumer to easily grip the tab and pull downward,
breaking the upper seal and opening the package. The inner layer of
the package has score lines. Consequently, as the consumer breaks
the upper seal, the package continues to tear along the direction
of the score lines. Once opened, the package resembles a plate.
Further, the torn top portion of the package can be used as a
place-mat upon which cups or drinks or other items may be
placed.
[0010] The package is capable of being produced on a vertical,
form, fill, and seal machine with only minor alterations. First, a
film is obtained wherein the first layer, or product side, of a
film web comprises score lines. The film is oriented so that it
preferentially tears in the direction of the score lines. The
resulting film is fed to a vertical, form, fill and seal machine.
The package is then formed into a tube, sealed at the bottom,
filled with product, and then sealed at the top with a peelable
seal. The peelable seal is made peelable by adjusting such factors
as time, temperature, pressure, as well as the geometry of the
seal. Further, the peelable seal has a force distributing
configuration which directs the force downward and outward along
the package as the consumer opens the package.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The novel features believed characteristic of the invention
are set forth in the appended claims. The invention itself,
however, as well as a preferred mode of use, further objectives and
advantages thereof, will be best understood by reference to the
following detailed description of illustrative embodiments when
read in conjunction with the accompanying drawings, wherein:
[0012] FIG. 1 depicts a cross-section of an exemplary prior art
packaging film.
[0013] FIG. 2 depicts a vertical form, fill, and seal machine that
is known in the prior art.
[0014] FIG. 3 depicts a perspective view of one embodiment of a
package in the instant invention.
[0015] FIG. 4 depicts a top planar view of one embodiment of the
instant invention wherein the top has been torn to reveal a plate
of product.
[0016] FIG. 5 depicts a cross-section of a packaging film of one
embodiment of the current invention.
[0017] FIG. 6 depicts the formation of the packaging film of FIG. 5
according to one embodiment.
[0018] FIG. 7 depicts a top planar view of the packaging film which
is used to produce the plate-mat package.
[0019] FIG. 8 depicts a perspective view of one half of the seal
jaws and jaw face used in one embodiment of the current
invention.
DETAILED DESCRIPTION
[0020] Several embodiments of Applicants' invention will now be
described with reference to the drawings. Unless otherwise noted,
like elements will be identified by identical numbers throughout
all figures.
[0021] FIG. 3 depicts a perspective view of one embodiment of a
package under the instant invention. The package preferably
comprises a flexible film web and more preferably comprises an
oriented film such as an oriented polymer material. As used herein
a flexible film web is a web comprising at least two flexible
layers. An oriented polymer material is a polymer material which
has been specially treated so that the long polymeric molecules
tend to align in a given direction, causing the material to
preferentially tear in that direction. The package is preferably
oriented so that it preferentially tears along its vertical axis.
The package in this embodiment further comprises a front panel 306
comprising a left and right side, a back panel 307 contiguous with
the front panel, a bottom seal 301, an upper seal 302, at least two
score lines 303 vertically oriented along the right and left side
of the front panel and running parallel from the upper seal to the
bottom seal, tear slots 304, and a tear tab 305. The bottom seal
301 is formed by heat seal jaws similar to those depicted in FIG.
2. It should be noted that the top portion of the bag comprises a
tear tab 305 which is an extension of the package film above the
upper seal 302. Thus, the top most portion of the bag between the
tear slots 304 and above the upper seal 302 is not sealed. Because
the front panel 306 is not sealed with the back panel 307 in this
area, a tear tab 305 is formed. Two or more tear slots 304 can be
made by any means known in the art such as a knife and anvil. It
can be appreciated that because the tear tab 305 is not sealed a
consumer can grip the tear tab with ease. Thus, a consumer can grab
the tear tab 305 on the top panel 306 of the package and easily
manipulate it as it is not sealed to the back face 307 of the
package. In some larger packages, the tear tab 305 will be large
enough for a consumer to grab with an entire hand. Even in smaller
packages, the tear tab 305 will be large for the consumer to
securely grab the tab with a plurality of fingers. After grabbing
the tear tab 305, a consumer can exert a downward force. The
downward force will follow the path of least resistance in the
direction provided by the tear slots 304.
[0022] Upon pulling the tear tab 305, the consumer's force will
first be directed upon the tip 308 of the upper seal 302. As will
be discussed in more detail below, the upper seal 302 is a peelable
seal which is typically easier to destroy. It can be seen that one
benefit of the upper seal 302 is that the seal comes to a tip 308.
As depicted, the upper seal 302 is a chevron seal. The use of a
chevron seal is shown only as a preferred embodiment and should not
be deemed limiting. Other possible examples include a semicircle or
any other shape that exhibits a force distributing configuration.
As used herein a force distributing configuration is a
configuration that concentrates the force at a force concentrating
area such as a narrow tip and then distributes the forces downward
and outward. Other shapes that do not concentrate the initial force
at a narrow tip can be used, but such shapes result in increased
force being necessary to initiate the tear and open the package.
The seal has a seal area of a defined width and length. In a
preferred embodiment the seal has a tip 308, defined herein as a
force concentrating area. In a preferred embodiment the seal area
at the tip is narrower than the width of the seal along the rest of
the seal. Such a configuration allows for even greater
concentration of force resulting in easier tear initiation. A
chevron seal is used as the upper seal 302 in part because of its
defined tip 308, In a preferred embodiment the width of the tip 308
of the upper seal 302 is between about 1/32nd and about 1/4th of an
inch and is narrower than the width of the seal 302 along other
portions of the seal 302. In a more preferred embodiment the width
of the tip 308 of the upper seal 302 is between about 1/16.sup.th
of an inch and about 1/8.sup.th of an inch. The downward force
exerted by the consumer will be concentrated on the tip 308,
resulting in less required force to destroy the seal 302 at the tip
308, thus initiating the opening of the seal 302. If the upper seal
302 did not come to a tip or was thicker, the force would be less
concentrated and consequently more force would be required to
destroy or open the seal.
[0023] When the seal is destroyed, the force exerted gets
distributed downward and outward along the package in the same
direction of the upper seal 302. As the forces distribute outward,
they run across a plurality (three in the embodiment illustrated)
of score lines 303a, 303b, 303c, 303d, 303e, 303f on either side of
the package. As used herein score lines encompasses lines which
have been partially scored into the material, completely slit
through the material, or perforated. In the pictured embodiment
there are three score lines 303a, 303b, 303c, 303d, 303e, 303f
which run the entire length of the package on both sides, left and
right, of the package. In one embodiment of the current invention,
it is preferred that these score lines 303a, 303b, 303c, 303d,
303e, 303f on either side be separated by about 1/10.sup.th of an
inch to about one inch. It is more preferable that the score lines
be separated by about 1/8.sup.th to about 1/2 of an inch. It is
most preferable that the score lines be separated by about 1/4 of
an inch. It is desirable, though not required, to form score lines
303a, 303b, 303c, 303d, 303e, 303f such that when the package is
filled with product the outermost score lines 303c, 303f are close
to the product edge. This results in a greater possible planar
surface area of the plate when the package is opened. In one
embodiment of the current invention it is preferred that the
outermost score lines be located from about 1/16.sup.th of an inch
to about four inches from the edge of the package.
[0024] As a consumer pulls down on the tear tab 305, the force will
run down the upper seal and into one of these three score lines
303a, 303b, 303c, 303d, 303e, 303f. Having multiple, or in this
case three score lines 303a, 303b, 303c, 303d, 303e, 303f on either
side is helpful, though not required, as it provides some room for
error; if the tear does not intersect the innermost slot, the tear
will continue until it intersects the outermost slot and the tear
will continue to run vertical with the length of the package. As
noted above, the oriented polymer material has been specially
treated so that the long polymeric molecules tend to align in a
given direction, causing the material to preferentially tear in
that direction. Thus, because the polymer material is oriented so
as to align with the score lines lines 303a, 303b, 303c, 303d,
303e, 303f, the material preferentially tears in the same direction
as the score lines 303a, 303b, 303c, 303d, 303e, 303f. If the
material was oriented perpendicular to the score line the material
would not tear along a straight path. The polymer material is
treated to cause this alignment in the formation of the material
before the film layers are selected for lamination.
[0025] FIG. 4 depicts a top planar view of one embodiment of the
instant invention wherein the top 401 has been torn to reveal a
plate of food. The top 401, once removed, can be used as a type of
placemat. For example, cups can be placed on the top 401 instead of
a coaster to protect a tabletop. Returning to FIG. 4, it can be
seen that the top 401 has been torn along the middle score lines
303e, 303b. Two score lines 303a, 303d are visible in the innermost
layer of the torn top portion 401. Additionally, two score lines
303c, 303f remain on the plate portion of the package. Thus, FIG. 4
shows an open package that has been opened with a tear following
the middle score line. Note that while this embodiment has been
shown with three score lines on either side of the package that is
not so limiting. Virtually any number of score lines, from one up,
is possible. Once the package is open, as depicted in FIG. 4, the
bag sits firmly on a surface. The torn top 401 reveals the package
contents. In one embodiment the bag comprises snack foods such as
potato chips. A consumer would be able to consume or use the
package's contents without the need to balance the bag for fear of
spillage. Further, the open surface of the instant invention offers
a greater relative surface and allows for easier removal of the
product contents compared to prior art bags that offered only a
relatively small opening for removal of the product. Thus a
consumer can easily open the package using the tear tab 305 and
place the open package on a surface, utilizing the open package as
a plate.
[0026] Referring now to FIG. 5, one aspect of the instant invention
becomes clear. Whereas in FIG. 1 the outside of the bag is an OPP
layer 102 and the product side of the bag is a metallic OPP layer
106 with a sealant 108, the instant invention has those layers
reversed. Referring to FIG. 5, in one embodiment the outermost
layer of the instant invention is a metalized OPP layer 106 with a
sealant layer 108. As discussed above, the sealant layer 108 can
comprise barrier properties. As used herein barrier properties
means any layer which provides a barrier to oxygen or moisture and
helps to retain taste and freshness of the product contained
therein, An OPP layer 102 is the innermost, product side layer of
the package. An adhesive layer 104 is between the OPP layer 102 and
the metalized OPP layer 106, 108. Thus, whereas the metalized layer
106, 108 was on the inside of the package in the prior art, in the
instant invention the metalized layer 106, 108 is actually on the
outside of the package. The reason for this arrangement can better
be seen referring back to FIG. 3. As discussed above, FIG. 3 has
three pairs of score lines 303a, 303b, 303c, 303d, 303e, 303f that
run the entire length of the package. It is a preferred embodiment
of the instant invention that these score lines be on the innermost
layer of the invention of the bag. As a consumer pulls on the tear
tab 305, the force destroys the seal at the tip 308 of the upper
seal 302 and continues downward and outward until the tear
encounters a score line 303a, 303b, 303c, 303d, 303e, 303f. Because
in this embodiment the score line is formed in the innermost layer,
when the downward force is applied, the innermost layer breaks and
tears in the direction of the force. This in turn causes the
outermost layers to tear in the same direction and location. Thus,
because the score lines 303 are located in the innermost layer
which is below the outermost layer, any force to separate the
innermost layer must cause a tear in the outermost layer.
[0027] Referring back to FIG. 5, it becomes obvious that there are
many different possibilities for film layers that would result in a
similar outcome of the current invention. The basic requirements of
the instant invention are that one layer comprise a score line and
that one layer comprise barrier properties. These barrier
properties are essential in keeping oxygen and moisture from
contacting and adversely affecting the product within the
container. It can be appreciated that while one embodiment has
stated the use of OPP as the innermost layer, other materials can
be suitably used. Virtually any layer that is capable of laminating
or adhering with another layer comprising barrier properties may be
used for the innermost layer. Likewise, while a metalized OPP layer
has been described for the outer layer, virtually any layer which
comprises adequate barrier properties can be used.
[0028] FIG. 6 depicts the formation of making score lines 303a,
303b, 303c, 303d, 303e, 303f in one embodiment. FIG. 6 depicts the
formation of the packaging film of FIG. 5 wherein the innermost
layer of the package is slit completely through. It should again be
noted that this invention is not limited to situations where the
innermost layer is slit completely through. Other methods such as
scoring or perforating may also be used. FIG. 6 depicts a slightly
altered method which was disclosed by commonly owned U.S. Pat. No.
7,189,300 B2 to Knoerzer et al. which is incorporated herein. First
an OPP layer 102, which in this embodiment is the innermost film in
the package, is slitted. It is slit by slitters 603 resulting in a
film with parallel score lines. If three score lines on either side
of the package are desired, then there will be six total slitters.
After an OPP layer 102 has been cut resulting in score lines 303,
the OPP layer 102 is laminated using an adhesive 104 to the
outermost layer comprising an OPP metalized layer 106 and a sealant
108. The resulting film 500 comprises an OPP layer 102 with score
lines laminated to an OPP layer 106, 108 which comprises barrier
properties. It should be noted that while reference has been made
to a single film layer, it is possible, and may be preferred that
each layer comprise multiple layers.
[0029] FIG. 7 shows a planar view of the composite film 500 that
will make up one example container or bag. The width 704 and length
706 of each composite film 500 can be varied to produce bags of
various sizes. Note, that if the composite film 500 is fed to a
traditional form, fill, and seal machine, the composite film 500 is
in a continuous sheet. It is then formed into a tube, sealed at one
end, filled, sealed at a second end, and cut to form the resultant
bag.
[0030] As an example, to produce a five inch wide bag, the width of
the composite film 704 will be about eleven inches. If three score
lines are desired on either side of the bag, and each score line is
separated by about one-quarter of an inch, then the distance 705
between middle score lines 303b, 303e will be about four inches.
The distance 701 between the middle score line on the right 303e
and the right side of the film composite will be about 3.75 inches.
The distance 703 between the middle score line of the left 303b and
the left side of the film composite will be about 3.25 inches.
Thus, it is apparent that the distance 702 between middle score
lines 303b, 303e is dependent upon the width of the composite film
704, the distance between score lines 705, and the number of score
lines. Thus, if an eight inch bag is desired, with six score line
separated by about one-quarter inch, the resulting composite film
would have a distance of about seven inches between the left and
right middle score lines. Accordingly, if the package was opened
along the middle score line, the resulting plate would have an open
area width of about seven inches. It should be noted that the
dimensions and ratios stated above are for one preferred embodiment
and are given only as an illustrative example. Many other
dimensions and ratios may also be preferred and can be obtained
without varying from the scope of this invention.
[0031] The composite film 500 is then fed to a traditional form,
fill and seal machine, similar to that shown in FIG. 3 but with
minor alterations. The film is fed such that the score lines are
parallel to the direction of film travel. An alteration made to a
traditional form, fill, and seal machine includes replacing the
heat seal jaws 226 with a modified jaw that provides both the
vertical bottom seal 310 and the upper seal 302 as seen in FIG. 3.
These modifications can best be understood by reference to FIG.
8.
[0032] FIG. 8 depicts a perspective view of the seal jaws and jaw
face used in one embodiment of the current invention. FIG. 8 only
shows a perspective view of one of the seal jaws and in operation
two seal jaws would act in concert to form both seals. The top
portion of FIG. 8, the bottom sealer 801, is a horizontal seal
which makes the bottom seal 301. The bottom portion of FIG. 8, the
upper sealer 802 seals the top portion of the bag by making upper
seal 302. The upper sealer 802 as depicted has the shape of an
inverted "V" and would result in the chevron seal shown in FIG. 3.
It should be noted that the upper sealer 802 can comprise various
shapes. It naturally follows that the upper sealer 802 can produce
an upper seal 302 with many different shapes such as the chevron or
a semi-circle. Virtually any shape which directs force downward and
outward can be utilized. It can be seen that there will be a layer
of film 805 defined by the length between the distance of the
bottom sealer 801 and the upper sealer 802 that is not sealed. This
is what results in the tear tab 305 that provides for easy opening.
It should be noted that the lengths of both the bottom sealer 801
and the upper sealer 802 exceed the width of the bag to be sealed.
If the lengths of the seals do not exceed the width of the bag,
then the entire bag will not be sealed, and oxygen and moisture
will be able to penetrate the bag.
[0033] In operation, the upper sealer 802 and the bottom sealer 801
are separated by a distance defined by the length of unsealed film
805. This distance will vary from about half an inch for smaller
bags to about four inches or more for larger bags. The bottom
sealer 801 is located above the upper sealer 802 by a distance 803
defined by the separation from the tip of the upper sealer 808 to
the bottom sealer 801. This distance 803 will vary with the size of
the bag. Suitable distances include from about one-half an inch for
smaller bags to about four inches or more for larger bags. In
operation, while the bottom sealer 801 is forming a bottom seal 301
for a bag above the bottom sealer 801, upper sealer 802 is forming
an upper seal 302 for a bag located below the bottom sealer 801.
After the two seals are formed, a knife, or other means (not shown)
cuts the film beneath the bottom sealer 801 to form two separate
bags.
[0034] It should also be noted that the seal produced by the upper
sealer 802 is typically different from the bottom seal 301 in that
the upper seal 302 is peelable. It should be noted however, that in
some embodiments it may be desirable that the bottom seal 301 also
comprise a peelable seal. As used herein a "peelable seal" is a
seal which can be broken along a specified direction of travel, and
which is typically easy to open. In one embodiment the peelable
seal requires less force to destroy than a destructive seal. A
destructive seal is a seal that cannot be opened without tearing.
In many embodiments the peelable seal is easily opened with two
hands. It is possible to produce a peelable seal in many ways which
are discussed below. In one embodiment, the geometry of the upper
seal 302 is manipulated to produce a seal which is easier to open.
For example, in one embodiment the peelable upper seal 302
comprises a line seal. A line seal is a very narrow seal. Because
the line seal is narrow, it requires less force to destroy than a
wider seal. Thus, the peelable upper seal 302 can comprises an easy
to open line seal whereas the bottom seal 301 comprises a
traditional permanent or destructive seal. In some embodiments, the
upper seal 302 and bottom seal 301 comprise the same seal type, for
example a permanent seal, but the upper seal 302 is narrow making
it easy to open and thus peelable. In another embodiment the
peelable upper seal 302 comprises resin in what is sometimes
referred to as a peelable sealant by design. Typically, in such an
embodiment resin is applied to the entire film of the package. Upon
the application of heat and pressure a seal forms between the two
films comprising layers. The strength of the resultant seal is
adjusted by varying the amount of heat applied to the seal, the
pressure applied to the seal, the length of time the heat and
pressure are applied to the seal, as well as the geometry of the
seal. Thus, two seals of varying strength may be made by varying
the temperature and pressure applied to a given seal. Likewise, as
discussed above, one seal can be weaker and thus easier to open
than a second seal if it is thinner than the second seal. In other
embodiments the resin may be applied selectively to the area being
sealed resulting in a peelable seal. In yet another embodiment the
peelable upper seal 302 comprises a cold seal, for example, glue.
Thus, there are many methods which produce a peelable seal. Any of
these methods may be used to produce upper seal 302. In many
embodiments of the current invention the upper seal 302 requires
less force to destroy than the bottom seal 301. The reason the
upper seal 302 needs to be peelable is that in the operation of
this bag a consumer grabs the tear tab and pulls downward. As the
consumer pulls downward, the force of the tab being pulled downward
along the length of the package will be sufficient to separate the
front and back layers of the package so that the seal is destroyed
and the package is opened. Consequently, the upper seal 302 needs
to be peelable to allow for this operation. If the seal was not
peelable, then the package will just rip apart instead of following
the path of the seal. Further, if the seal was not peelable then
more force is typically required to destroy it. It should now be
noted that while FIG. 8 depicts the upper sealer 802 and the bottom
sealer 801 as being on the same seal jaw 803, it is possible, and
it may be more desirable to have each sealer on its own seal jaw.
Such an arrangement allows increased flexibility in forming seals
with different attributes.
[0035] In summary, the invention allows the production of a
flexible film having an easily opened package that when opened
operates as a plate. Many other variations are possible without
straying from the intent of this inventive disclosure and will be
obvious to one of ordinary skill in the art.
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