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The present invention relates to a process for the manufacture of an easy open device for
"Flow Pack" or similar packages with longitudinal seams and transversal closures, an
opening device obtained through said process, and the package using it.
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More specifically, it relates to a process for placing a detaching or easy open strip in packages
with longitudinal seams and transversal closures [in] which, because of their current
manufacturing characteristics, said opening is made by tearing, with the risk of spillage of the
packaged product and subsequent destruction of the package. It could be said that package
manufacturing techniques are divided into packages with and without longitudinal seams and
transversal closures. The first are the so-called "Flow Pack" packages and the second are the
so-called "portfolio" and/or wrapper packages.
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Portfolio-type packages are produced by the movement in the machine direction of the
already-printed packaging film, said printing generally being readable in the direction
perpendicular to the film's movement. The product to be packaged arrives at the film
perpendicularly to its movement, supported by disks on both ends. At the same time, a
detaching or easy open strip is incorporated longitudinally into said film by an applicator
head. The detaching strip comes on a spool. While continuously unwinding, it is fixed with
adhesive to the internal face of the packaging film in an area near one end of the product to
be packaged. Said strip is not longer than the width of the package, generally not exceeding
15 cm, and one of its ends is exposed by lateral incisions to allow for manual detachment so
the packaged product can be accessed.
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These types of machines have cylinders that adjust the area where said detachable strip will
be placed, but their degree of precision is relative, so there is generally displacement which
affects the proper operation of said strip. Also, during the process of constructing the
package, the free end for tearing said strip may not match up with the circumference it should
describe. Consequently, when it does not close over itself, the tear is not clean. In some cases,
said strip is not even where it should be. As indicated, once the package is constructed with
its detachment strip incorporated, one frangible end is left free to open it. This free end, not
attached to the rest of the package, is made with at least one cut in one side of the strip. If
there are two cuts to both sides, they may not be symmetrical because of synchronization
problems, which makes a neat opening even more difficult to achieve. If this occurs, more
force must be applied than that required for opening, which distorts it and entails high risk for
the product and package integrity.
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This type of package uses heat activated adhesive to seal the ends, because of which the
product to be consumed can also be damaged, due to the pressure of the disks and the
temperature applied, as in the case of packets of crackers, in which the first and last are
generally damaged.
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The undesired effects that may accompany the wrapping or portfolio technique, plus their
hermetic closure, motivated the appearance and the increasingly frequent use of "FlowPack"
type packages which, because of their transversal packaging characteristic, could not, until
now, have an easy open device. There are two types of Flow Pack packages, those generated
horizontally and those generated vertically, also called sacks.
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In horizontal packaging, the product is positioned on the printed film which will make up the
package in [a] direction parallel to the readable printing, because of which it must enter
parallel to the machine direction, which means perpendicular with respect to the
aforementioned packages that are produced longitudinally (or "portfolio"). The film closes
over itself on one face of the package, producing a longitudinal fold or seam which is heat
sealed. The same occurs on the ends. Due to the manufacturing characteristics of this type of
package, the application of a detaching strip which is continuous and in the machine
direction, as in the case of longitudinally-manufactured packages, involves several
difficulties, such as:
- It would use a longer strip, with the consequent higher cost
- It would interfere with the heat seal areas, making [the sealing] difficult, acting as a
potential contamination factor.
- It would expose the entire packaged product without the ability to be re-closed,
with the consequent product deterioration.
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In the case of vertical or sack type "Flow Pack" packages (filled gravimetrically or
volumetrically), the process is different because it is not continuous. Its intermittent nature is
due to the fact that one end of the package must be sealed and the longitudinal seam must be
generated so that, when gravity causes the product to fall, it is confined in the package.
Subsequently, the other end (where the product enters) is sealed, thus generating the base for
the next package. The inclusion of a detaching strip has also not been used because of the
problems previously set forth with respect to the conventional processes for inserting said
strips.
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Therefore, and in keeping with what has been set forth, at this time, there are no known
processes for including detaching (also known as "easy open") strips in packages with
longitudinal seams and transversal closures, commonly known as "Flow Pack."
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Based on what has been set forth, the need to develop a process for the manufacture of an
easy opening for these types of packages is clear, since at the current time they are opened
only by tearing one of the ends or through the longitudinal seam (which can be located
anywhere on the package). In the majority of cases, this causes spillage of the product
because of the force needed to break the heat seal and, in some cases, destruction of the
package.
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Another as yet unresolved problem is reclosing the packages after opening. Generally, once
the packages are opened, they are closed with a rubber band, a clasp, a clip, or any other
prehensile implement. It is well known that in food products with a high fat content, rapid
oxidation occurs, producing the so-called "sogginess" (and possible sticking in the package),
destroying crispness and freshness. In the case of Flow Pack packages, this difficulty
increases because, as in the majority of cases, the package is in very poor condition after
being manually opened and it is very difficult to reconstruct it to close it by any of the means
mentioned. So there is a need to open these packages in a non-traumatic manner and then
close them so they keep the packaged products fresh.
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Another difficulty arises in the case of promotions or economy packs of any kind that include
more of a product at the same time. In the case of wanting to package, for example, three
packets of crackers for a promotion, double packaging is necessary. First, each product
individually, and then grouping them in a single package, either with a wrapping film of
sealed polyethylene or in a closed box. This is so because the difficulties mentioned with
respect to the destruction of the packages with longitudinal seams are aggravated even more
in this case, since, if there were no individual packages inside the collective package, many
products would be exposed, and, in the event of its destruction by tearing, significant spillage
would result. Also, the cost of this double packaging is so high that, in the majority of cases,
promotions do not achieve their expectations or objectives.
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Therefore, the purpose of using the present invention is to provide a process for inserting a
detaching or "easy open" strip in Flow Pack or similar packages with longitudinal seams and
transversal closures, manufactured horizontally or vertically.
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Another purpose is that said detaching strip be easy to detach.
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Still another purpose is that the opening procedure not endanger the integrity of the package.
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Yet another purpose is that the process for including a detaching strip not increase costs.
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A further purpose is to provide an easy closure for packages with longitudinal seams and
transversal closures.
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The following is a specific description of some embodiments of the invention with reference
being made to the accompanying drawings in which:
- Figure 1 shows a longitudinal packaging or wrapping machine.
- Figure 2 shows a horizontal Flow Pack packaging machine with the inclusion of the purpose
of the present invention.
- Figure 3 shows a vertical or sack type Flow Pack packaging machine with the inclusion of the
object of the present invention.
- Figures 4 A to C show an easy open sequence with the free end of the detaching strip located
on the longitudinal seam of the Flow Pack packages.
- Figures 5 A to F show an easy open and closing sequence when the end of the detaching strip
is not placed on the longitudinal seam of the Flow Pack packages.
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Referring firstly to Figure 1 of the drawings, there is shown a longitudinal wrapping or
portfolio packaging machines. Packaging film 1 on which the product to be packaged is
deposited 2 is moved, with printed face 3 down and readable perpendicularly to the machine
direction. The product to be packaged enters through one side on a conveyor belt 4
perpendicularly to the machine direction, as indicated by the arrows. This process
incorporates a detachable strip 5, which is attached to the internal (unprinted) face 6 of the
packaging film 1. This detachable strip is continuously unwinding from the spool 8 so that,
after the final cut, it will surround the entire perimeter of the package 7. Its final length is, in
the majority of cases, not greater than 15 cm. This, of course, depends on the product to be
packaged.
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Figure 2 shows how horizontal Flow Pack packages are produced. The packaging film 1 is
moved, with printed face 3 up and generally readable, parallel to the machine direction, as
indicated by the arrows. At a certain point, the product 2 to be packaged is incorporated in the
machine direction. Then the packaging film 1 is folded, wrapping the product 2, and a
longitudinal seam 12 is generated. This seam is preferably located in the centre of the
package, which is heat- or cold-sealed. The same occurs with the ends of the package 9,
which are pressed, heat- or cold-sealed, and cut. In this way the process keeps mechanical
elements from coming into contact with the product 2 to be consumed and jeopardizing its
integrity. If the process included a spool 8 containing a strip 5, such as the one described in
Figure 1, which is unwound continuously and whose detaching strip 5 is attached to the
internal face of the package 3, an undesired opening area that would expose all of the product
would be generated; it would also have to span areas that are sealed, which could result in
product 2 deterioration.
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Figure 2 shows a spool 8 with a rolled plastic siliconed carrier or liner 10 that has detaching
strips 5 not longer than the width of the packaging film 1, which is the object of the present
invention. Said strip 5 has adhesive on its printed face; this process is called "occluded
printing." The ink is occluded because of the requirement to not expose the printed face to
the package contents 7.
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The siliconed carrier 10 is punched and, using an applicator head (not shown in the figure),
the detaching strips 5 are applied to the internal face of the packaging film 1 continuously,
accurately aligned.
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Said strips 5 must be thick and rigid enough so that, once the cut is initiated, the subsequent
release of the material accompanies their detachment.
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As indicated, these detaching strips 5 are placed along the width of the siliconed carrier 10
that supports them. This means that they will be deposited transversally with respect to the
machine direction and perpendicular to the readable printing on the packaging film 1. The
release area 17 figures 5 and 6 can be generated on just one face of the package 7 or on all of
them (with total detachment of the portion of the package above said strip). The fact that the
release area 17 figures 5 and 6 is not the total perimeter of the package 7 makes it possible to
use an easy open/close element 11 Figures 3 and 5 that enables said package 7 to be closed
for subsequent use, thus preserving the product to be consumed. This easy open/close
element 11 Figures 3 and 5 can either be affixed to one face of said package 7 or inside said
package 7 as a self-sticking label.
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Said detachable strip 5 can be positioned on any part of the package 7. Everything will
depend on the type of product to be consumed. In the case of disposable tissues, it could be
inserted in the middle of the package 7, but in the case of crackers, a position near one of the
ends 9 would be suitable. Application is made with a standard aligning applicator head
known in the art which, through the optical reading of a reference element on the packaging
film 1 (not provided in the figure), indicates where said detachable strip 5 should be affixed.
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Optical alignment is much more accurate than mechanical devices in relation to the
aforementioned problem of displacement, with which the associated problems regarding
release are also solved. The place where said strip 5 is to be affixed is previously input
manually in the production line control logic (PLC), which in turn transmits the information
entered to the optical reader, which activates the applicator head when said strip 5 must be
affixed to the packaging film 1.
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Figure 3 shows a packaging machine for vertical Flow Pack packages, also called sacks 7.
Gravity plays an important role in this process. The film 1 moves vertically (see arrow),
producing first a package 7 with a longitudinal seam 12 generated by means of longitudinal
clamps 22, a sealed lower end 13 generated by means of transversal clamps 23, and an upper
end 14 originally opened by means of a shaping shoulder 21. Through it enters the product to
be packaged, which is gravimetrically or volumetrically measured out through the hopper 21.
The subsequent heat sealing of said upper end 14 by action of the transversal clamps 23
shapes the lower end 13 of the next sack, and so on. This process is not continuous, since it is
necessary to wait for the package 7 to be filled in order to move on to the next. The purpose
of the present invention is to participate in the packaging process through the previously-described
spool 8, which has a siliconed carrier or plastic liner 10 that supports the detaching
strips 5, which, by means of an applicator head (not shown in the figure), are affixed
transversally to the packaging sheet 1 and aligned with a through cut 18 generated by the first
cutting machine 24. Then the easy open/close element 11 is attached, also aligned and on the
area of said cut 18, by means of another applicator head (also not shown).
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Figures 4 A to C show an example of [the] opening sequence for the Flow Pack packages
from the longitudinal seam. There are two small incisions 15 in said seam 12 where one of
the ends 16 of the detaching strip 5 is located for easy grasping and to generate the release
area 17 since, as is well known, said longitudinal seam 12 is not attached to the package 7
and moves freely. It could be made a requirement that the detaching strip 5 be located on the
face that is not affected by the seam 12 or it could be required that the desired length of the
strip not touch the seam; this example will be described in the next Figure.
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When one end of the detaching strip 5 is not positioned on the seam 12 and, therefore, cannot
be easily grasped except after ripping, it becomes vital to include an element to facilitate that
task Figures 5 A to F. Said element should be directly attached to that end of the detaching
strip 5 and to the area of the through cut 18 to generate the release area 17. Part of this
element's surface should be self-sticking to establish that connection, and the rest of this
element's surface should be non-sticking so it can be easily grasped, as occurred in the case
of the free end 16 of the detaching strip 5 described in Figure 4 A. This aforementioned easy
open/close 11 element will be described below.
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As can be seen in the sequence of Figures 5 A to F, for the best preservation of the products
which a package 7 contains, an easy open/close element 11 could be used on one of its faces
19 with the part of the surface that is attached blocking said through cut area Figure 5B
reference 18) and one end of the detaching strip (5). The other part of the surface of said easy
open/close element 11 does not contain adhesive, so it can be easily grasped by the end user
Figure 5 A and can begin the release area 17. When said release area 17 Figure 5B is begun,
it extends to one side of the package 7 Figure 5C, in turn generating an upper flap 20. When
the opening of the package 7 Figure 5D is complete, said upper flap 20 folds over itself 5E
and over the release area 17 and then adheres to one of the faces of the package 7 (Figure 5F)
using said easy open/close element 11 previously detached from the detaching strip 5.
Finally, the affixing of the detaching strips 5 to the internal face of the film 3 of the package 7
may be accomplished on line in real time via a spool 8 that is unrolled as the packages 7 are
constructed, or off line, in which case the packaging film 1 is ready to be incorporated after
the packaging process with the strips 5 included. This latter case involves unrolling the entire
spool 8, affixing the strips 5 at intervals controlled by optical and/or mechanical reading, and
ultimately rewinding said spool 8.
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Although the present invention has been described according to a specific implementation
method, all persons skilled in the art will understand that various changes can be made and
that equivalents can be substituted without departing from the true scope and spirit of the
invention. In addition, many modifications can be made to adapt a situation, a material, a
combination of materials, one or more specific steps of the process, to the purpose, the spirit,
or the scope of the present invention. The purpose of all these modifications is inclusion in
the scope of the claims attached hereto.
