Note: Descriptions are shown in the official language in which they were submitted.
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11-618CA RECLOSABLE B~G ~ND ~ET~OD OF MA~I~G
~elated A~Plications
This application is related to co-pending applica-
tion, Serial No. 614,569, entitled "Packaging Machine
and Method" the disclosure of which is incorporated by
reference.
Back~round of the Invention
1. Field of the In~ention.
The invention relates to packaging, and more
particularly to a chain of interconnected reclosable
plastic bags, and the method of making a chain of
reclosable plastic bags.
2. Description of the related art.
Reclosable flexible plastic bag containers are
known. In one proposal an individual bag has a front
wall which extends beyond a back wall to form a closure
flap which folds over the bacX wall. An adhesive strip
is placed on the flap to form a closure. This bag,
however, lacked a header for hanging the bag, was
complicated to produce, and did not provide an attrac~
tive appearance when loaded with a bulky product.
Another proposal provided a single layer of plastic
folded back on itself and sealed along the bottom and
sides. Inside the bag a closure was formed with
interlocking parts which joined the sides of the bag
together. The bag was initially torn open but could be
resealed by the interlocking parts. This bag did not
provide a header for hanging the bag, did not lend
itself to automatic filling, and did not provide an
attractive appearance when loaded with a bulky product.
In addition, the process of forming the bag involved an
additional extrusion for forming the interlocking parts.
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Other known flexible plastic bag constructions
could not be produced efficiently in volume quantities,
did not lend themselves to bag filling machines, failed
to provide means for hanging the bag for display
purposes, or lacked an attractive display appearance.
Production of chains of flexible plastic bags is
now well known. Some such chains are formed of one row
of interconnected bags joined side by side. For
example one proposal folded a single layer of flexible
plastic back on itself leaving a f old edge and an open
edge. Seals were providPd to form headers and sides to
the individual bags. The individual bags were filled
from the open edge and then sealed to close the bag.
The ba~s were then separated from the chain. This
arrangement had no recloseability and lacked a desirable
appearance when filled with a bulky product.
Other known chains of flexible bags did not lend
themselves to efficient production in volume or a high
volume filling operation. Other known proposals lacked
recloseability and the ability to hang in a display.
Summary of the Invention
The present invention provides chains of bags, each
o~ which, when loaded with a bulky material to form a
package, hangs on a display rack with a substantially
flat front wall and a bulged rear wall. This produces
an attractive commercial product.
The provision of a package for products such as
nylon stockings that are bulky that can hang from a
point of purchase display with a relatively flat front
produces one of the outstanding advantages of the
invention. Point of purchase display packages are
typically imprinted to provide a prospective purchaser
with source identity through a trademark and information
as to the contents of a package. A ~lat package
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facilitates customer discernment of a message imprinted
on the package. By contrast circular packages often
used for bulky products provide limited information to a
prospective customer unless that customer in one way or
another scans around the circular package. Moreover a
flat hanging package with an attractive presentation of
source identification and of product information
enhances the potential for an impulse purchase of a
product.
In addition, each of the bags of the present
invention is reclosable. This feature permits the
product to be examined in the store by a prospective
buyer without destruction of the packaging. The
reclosable bag may be reused after the sale since it i5
not destroyed by opening.
Each finished plastic bag of the chain includes a
front wall which remains substantially flat when the bag
is loaded and a rear wall joined to the front wall along
its bottom and sides. When th~ bag is loaded with a
bulky product, the rear wall bulges outwardly in
response to pressure from bag contents more than the
~ront wall. The bag includes a header and an opening
formed near the top of the rear wall and adjacent the
header. A flap extends downwardly from the header
partially overlapping the rear wall and overlying the
opening. A resealable adhesive between the flap and an
adjacent portion of the rear wall releasably by secures
the two together to close the opening.
The chain of bags of the present invention may be
produced at high volume rates and are well suited for
use with a high volume bag filling machine such as that
disclosed in the referenced co-pending application
entitl~d "Packaging Machine and Method." The chain of
the novel bags comprises a plurality of bag elements and
lines of weakness between the bag elements.
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The present invention also relates to a new
process for forming two chains of inter-connected bags.
The process produces two chains of inter-connected bags
having the described advantageous characteristics. The
process produces two chains of the described bags at
high production volumes.
The m~thod starts by conveying a continuous web of
plastic film from a supply along a path. The continuous
web is folded lengthwise to form a double layer. The
folded web is slit longitudinally to produce two layers
of different widths positioned in a confronting
relationship. Next flaps are formed at intervals along
both edge portions of the wider layers. The flaps and
adjacent header portions of the wide layer are folded
over the other layer and sealed along a line adjacent to
the flaps to form headers. The layers are sealed
together along transverse lines located, longitudinally
speaking, between the flaps. The transverse seals are
then perforated creating lines of weakness between each
adjacent pair of bags. The continuous web is then slit
and sealed longitudinally along its center to form two
chains of bags. Further steps of applying adhesive
between each bag flap and the associated rear wall of
the same bag and of ~orming a hole in each header for
hanginy the bag are also performed.
Accordingly the objects of the invention are to
provide a novel and improved chain of bags, each of
which is especially suited for packaging bulky
products and a process of making such chains of bags.
Brief Description of the Drawinqs
Figure 1 is a side elevation view of a single bag;
Figure 2 is a perspective view of a chain of
connected plastic bags according to the present
invention,
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Figure 3 is a schematic perspective view of process
steps showing a web being folded, cut and unfolded;
Figure 4 is a schematic perspective view of a
process of flaps being formed and folded in the web of
Figure 3;
Figure 5 is a schematic perspective view o~ the
step of folding flaps inward;
Figure 6 is a schematic perspective view showing a
process step of forming headers in the web of Figure 5;
Figure 7 is a schematic perspective view of a
process step of raising a flap, applying adhesive to
the web of Figure 6, and punching a hole in the header;
and
Figure 8 is a schematic perspective view showing
process st~ps of forming side connections, forming lines
of weakness, and dividing the web of Figure 7.
Description of the Preferred Embodiment
Referring to Figures 1 and 2, a package in the form
of a finished and loaded plastic bag 10 is provided.
The bag 10 is shown hanging from a display hanger 11
projecting through a hole 12a in a header 13. The bag
includes a front wall joined to and depending from the
header 13. The front wall 14 remains substantially
flat when the bag 10 is loaded with a light but bulky
product such as nylon stockings. The bag includes a
rear wall 15 which bulges outwardly in response to
pressure from the bag contents more than the front wall
14.
~he bag 10 includes side connections 16, 17
defining side edges and, once loaded and sealed to form
a package, a permanent bottom connection 18 joining the
front and rear walls 14, 15A The bag 10 has a top end
19 and bottom end 20.
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The bag 10 includes an access opening 21 formed in
the rear wall 15 immediately below the header 13. A
flap 22 extends from the base of the header 13~ The
flap 22 partiallv overlaps the rear wall 15 and covers
the access opening 21. An adhesive 23 placed between
the flap 22 and an adjacent portion of the rear wall lS
resealably connects the flap 22 to the rear wall 15.
The resealable flap 22 allows the contents of the ba~ to
be examined b~v prospective purchasers and removed after
purchase without breaking the bag. Further, it provides
the purchaser with a bag that may be subsequently used
for other purposes.
Referring to Figure 2, a chain 24 of interconnected
plastic bags 10 is shown. The bags are connected
together by lines of weakness 25. First and second
temporary openings 26, 27 are formed in each bag 10 near
the bottom end 20 for conveying the bag on a mandrel in
a subsequent filling operation. The openings 26, 27 do
not survive the bag filling process and are not a part
of the final product seen by the customer. The first
and second side connections 16, 17 terminate a predeter-
mined distance from the bottom end 20 of the bag leaving
a small unsealed distance along the sides of each bag
between a termination point 28 of the side connections
16, 17 and a temporary end connection 29. The temporary
openings 26, 27 and connection 29 serve to allow
conveyance of the bag on a mandrel in a bag-filling
process. The bag filling process is described more
fully in the referenced related application.
An important feature of the plastic bag 10 of the
present invention is the substantially flat appearance
of the front wall 14 when the bag 10 hangs on a display
hanger 11. The rear wall 15 bulges in response to the
force of the bag contents more than the front wall 14.
This gives the bag a pleasing appearance. The front
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wall 14 is directly secured to the header 13 while the
rear wall 15 is not. The rear wall 15 is secured
indirectly to the header 13 through the adhesive 23 and
the flap 22. This results in the rear wall 15 expanding
and taking up the bulge of the bag contents.
Figures 3-8 illustrate the steps of a process for
forming two chains 24 of inter-connected plastic bags.
The process begins by creating a continu~us layered web
30 of two confronting layers 31, 32. This may be ac-
complished by feeding separate webs of plastic film fromtwo sources and placing the separate webs in a confront-
ing relationship to form a layered web 30. In the
preferred and illustrated embodiment, however, the
layered web 30 is created by feeding a single continuous
web 33 of plastic film from a single supply to a V-board
34. The film 33 is fed off center over the V-board 34
as shown in Figure 3. The film 32 is continuously cut
longitudinally at an off-center position dividing the
web into twc parts 31, 32 of unequal width. The V board
34 and a set of V-board rollers 35 achieve the step of
folding the web 33 lengthwise forming a double-layer
continuous two-part folded web 30 of plastic film having
a fold 36. The narrower part has been referred to as
the first layer 31 and the wider part as the second
layer 32.
The step of cutting the film longitudinally is
preferably done by a conventional slitting knife 37 as
the film is crossing the V-board 34. Thus, the film is
in two parts before it is folded and the fold 36 is
placed in the part that becomes the second layer 32.
After leaving the V-board rollers 35, the second
layer 32 of the double-layer web 30 is unfolded leaving
two confronting separate layers 31, 32 of differing
widths. The second layer 32 is unfolded by passing the
continuous web across an unfolder roller 38. The
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resulting two layers 31, 32 are now positioned in a
confronting relationship with the center of the first
layer 31 being aligned with the center of the second
layer 32. The proper alignment of the two layers 31, 32
is achieved by fixing the positions of the fold 36 and
the knife 37 with conventional web alignment mechanisms.
The web 30 next passes through a notch cutter 39
where notches 40 are formed at intervals along both
sides of the second layer 32 as seen in Figure 4. The
notches 40 define the flaps 22 of the individual bags
10 .
After leav.ing the notch cutter 39, the web 30
contacts a fc,lding roller 41 having a length less than
the width of the second layer 32. The outer edges of
the second layer 32, including the flaps 22, fold inward
as the web contacts the folding roller 45 as seen in
~igure 5. The outer edges of the second layer 37 are
further folded and pressed by conventional hold-down
members 42. ThP outer edges of the second layer 32,
including the flaps 22, now overlap the outer edges of
the first layer 31. The folding step is done at a
predetermined position so the resulting folds define the
top ends 19 of the bags 10.
The next step is to form the header seal lines 43.
The header seal lines 43 seal the second layer 32 upon
itself along lines located at a predetermined position
to form headers 13. The header seal lines 43 are
formed by conventional heat seal rollers 44. The header
seal lines 43 run parallel to the side of web 30
defining headers 13 on the individual bags 10. The
flaps 22 and headers 13 are locked in position by the
header seal lines 43, Thus a single sheet of film, the
second layer 32, forms the front wall 14, the header 13,
and the flap 22 of each ba~ 10.
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The next step is to apply adhesive 23 between each
of the flaps 22 and a portion of the first layer 31 on
both sides of the web 30. The step of applying the
adhesive 23 comprises raising the flaps 22 and applying
a bead of adhesive material 23 to the first layer 31 at
spaced intervals, or what will become the rear walls 15
of the individual bays 10. The flaps 22 may be raised
by any number of conventional means. In the preferred
embodiment, the flaps are raised by jets of air emitted
from compressed air nozzles 45. The flaps 22 are held
in a raised position for a short while by fingers 46
while the adhesive 23 is being applied. The adhesive 23
is applied by conventional glue guns 47. In the
preferred embodiment, the adhesive 23 is first heated,
and then applied with glue guns sold under the trademark
NORDSON SWIRLGUN by Nordson Corporation of Westlake,
Ohio.
After the headers 13 are formed in the web 30, the
holes 12 are punched at spaced intervals along both
sides of the web 30 at positions corresponding to the
center of each bag by a conventional punch 43. The
holes 12 permit the bags 10 to be hung from hangers 11.
The next step is to form side connections 16, 17.
The side connections are formed by transverse seals 49
of the layered web at spaced intervals located lon-
gitudinally speaking, between adjacent flaps 22. The
transverse seals 49 are heat seals joining the first and
second layers 31, 32 together. The seals 49 are formed
at positions which correspond to the side connections
16, 17 on the individual bags. The transverse seals 49
are not continuous across the width of the layered web.
Each transverse seal is interrupted near the center of
the layered web to form the first and second temporary
openings 26, 27 in the individual ~ags. The transverse
seals 39 do not extend across the headers 12. The
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transverse seals 49 are formed with a reciprvcating
interrupted heater bar 50. Opposing the heater bar 50
is a back-up drum 51.
The lines of weakness 25 are formed between the
bags 10. The lines of weakness 25 are formed along the
center line of the transverse heat seals 49. The lines
of weakness 25 allow the bags 10 to be separated from
one another without damaging the bags. In the preferred
and illustrated embodiment, the lines of weakness are
perforated lines formed by a conventional perforating
roller 52. Opposing the perforating roller is a
perforating back-up roller 53.
The final step is to longitudinally cut the
continuous layered web with a hot knife 54 along its
lS center to form two identical chains of bags. The hot
Xnife 54 seals the first and second layers 31, 32
together forming the temporary end connections 29.
The foregoing is considered as illustrative of the
principles of the invention. Further, since numerous
modifications and changes will readily occur to those
skilled in the art, it is not desired to limit the
invention to the exact construction and operation shown
and described, and accordingly, all suitable modifica-
tions and equivalents may be resorted to, falling within
the scope of the invention as claimed.
