Note: Descriptions are shown in the official language in which they were submitted.
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PROCESS FOR PACKING AND CREATING A HANDLE
Field of the invention
The invention relates to a process for packing absorbent articles in a pre-
made flexible bag and subsequently creating a handle element on-line.
Description of the prior art
Flexible bags are widely used to pack many different types of consumer
products. For instance, disposable diapers are typically packed in plastic
bags. The resultant bags are generally cumbersome and difficult to carry.
In order to facilitate consumer handling, handle elements are disposed on
the outer surface of the flexible bags. It has been customary to provide
separate handle elements of cardboard, moulded plastic or other suitable
materials that are glued, stapled or heat welded to the bag. US 4,252,269
teaches a bag of polymeric plastic material that has an opening at one
end and a gusset at the opposite end. Within the gusset, a handle is
welded to the front and rear panels of the bag along a fold fine. In
US 4,539,705, the handle strip is inserted in the gusset during production
of the bag and the ends of the handle strip are sealed to the adjacent wall
panels of the bag by a heat seal. US 5,054,619 refers to an easy open
flexible bag containing one or more stacks of flexible articles that
comprises a longitudinally oriented carrying handle, which is formed
independently of the bag. These handle elements are not entirely
satisfactory for all purposes and are often impractical in terms of material
utilisation, wastage of raw materials, complexity of process steps, stacking
and packaging, and effectiveness in that the handle element can tear
away from the carrier bag and expose the contents.
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Nevertheless, some bags have been specifically designed with
integral handle elements. US 5,026,173 describes a plastic bag having a
side panel with a carry grip area in which a carry strip portion is located.
The carry strip portion is formed between carry grip apertures or easily
breakable weakening lines. The carry strip is coplanar with the side panel
of the plastic bag and does not require seals of any kind. Protective and
reinforcement strips are provided underneath the carry grip apertures in
order to protect the contents of the plastic bag from external
contamination. GB 1 575 921 teaches a bag provided with a carrier
handle means where the handle is not located in loose flap members
protruding from a sealed top panel, but in a flap participating in the
wrapping of the articles. The products are first packaged in the bag, the
flap portion is then folded over the top side of the products and thereafter
the other flap portion is folded down along the vertical side of the bag and
adhesively attached to this side. US 4,913,693 provides a bag that
includes a side-to-side continuous handle, which is formed from pieces of
material that make up the sidewalls of the bag and a closed top formed
from a separate piece of material. DE 2 051 833 describes a means of
producing a package for hygienic articles comprising two strips of plastic,
one wider than the other. The preferred production method consists of
first forming a tube around the articles to be packed, then welding
transversely to separate the tubes or packages while at the same time
cutting the packages successively from one another. The resultant
package may contain a handle and a tear-off opening. The handle lies
between the welding seam used to seal the package shut and an
additional seam, which is present for stability purposes.
The above prior art, however, does not teach a process for packing
absorbent articles in a pre-made flexible bag by introducing the absorbent
articles through an area corresponding to the top pane! of the bag and by
subsequently creating a handle element on-line from the excess trim
material protruding from the top panel. Excess trim material is usually
included in a bag design to account for variations in the height of the
products to be packed and to allow for sealing variations, The exploitation
of this excess trim material according to the present invention leads to
such benefits as excellent material utilisation and a reduction in raw
material wastage. The advantage of the pre-made bag lies in the
flexibility that it offers to both suppliers, packagers and manufacturers.
There is no tying effect and therefore no need exists for the combination of
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an on-line packaging and bag manufacturing step as described in the prior art
document DE 2 051 833. The complexity of the manufacturing phase is thus
greatly reduced. Furthermore, with the aid of suitable reinforcements and
effective sealing techniques, a strong handle element mounting can be
formed which results in improved consumer confidence.
Summary of the invention
It is an object of an aspect of the present invention to provide a process
for packing absorbent articles in a pre-made flexible bag by introducing the
absorbent articles through an area corresponding to the top panel of the bag
and by subsequently creating a handle element on-line from the excess trim
material protruding from the top panel. A further object of an aspect of the
present invention is to provide a strong handle element mounting using
suitable reinforcements and effective sealing techniques.
In accordance with the objects of aspects of the invention, a pre-made
flexible bag for flexible articles is provided. Flexible articles are
introduced into
the flexible bag through an area corresponding to the top panel, which is
subsequently sealed at its top panel. At least one flap protruding from the
top
panel is left attached. The flap comprises a grip area and a grip area
perimeter. The flexible bag is pre-made before the introduction of the
flexible
articles and a handle element is shaped from the flap protruding from the top
panel, the handle element comprising a handle element perimeter. The
preferred embodiment comprises two flaps. The handle element comprises a
seal running along the handle element perimeter. In order to allow fingers or
hands to wrap around the handle, a grip area is formed. The reinforced
handle element can comprise flaps that are sealed together in the entire area
of the handle element except for the grip area or the flaps are further
reinforced at the handle element perimeter or the flaps comprise a seal
surrounding the grip area perimeter or the flaps comprise a seal abutting the
entire grip area perimeter.
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In accordance with one embodiment of the present invention, there is
provided a process for packing flexible articles in a flexible bag wherein
said
flexible bag is sealed at its top panel after introduction of said flexible
articles
leaving attached at least one flap protruding from said top panel of said
flexible bag, said at least one flap comprises a grip area and a grip area
perimeter, and wherein said flexible bag is pre-made before said introduction
of said flexible articles through an area corresponding to said top panel and
a
handle element is shaped from said at least one flap, said handle element
comprising a handle element perimeter.
Brief description of the drawings
While the specification concludes with claims particularly pointing out
and distinctly claiming the invention, it is believed that the invention will
be
better understood from the foregoing description in conjunction with the
accompanying drawings in which:
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Figure 1 is a front view of a pre-made flexible bag comprising a handle
element made on-line.
Figure 2 is a front view of the various design configurations existing for the
handle element of the pre-made flexible bag.
Figure 3 shows six different embodiments of sealing design configurations
that are suitable for the handle element of the pre-made flexible bag.
Detailed description of the invention
As used herein, the term "pre-made" refers to a bag in which the front,
back, top, bottom and side panels are all interconnected. As used herein,
the term "grip area" describes the area designed for gripping that is either
cut, punched or scored out. As used herein, the term "grip area perimeter"
represents the edge of the grip area. As used herein, the term "handle
element perimeter" represents the edge of the handle element.
Figure 1 shows a pre-made flexible bag 10 comprising flexible
articles. The flexible articles may comprise disposable absorbent diapers,
sanitary articles, incontinence pads or briefs, bandages and the like. The
flexible articles are typically compressed to between 20 and 70 percent of
their uncompressed volume and may be oriented either with all their waist
features directed upwards towards the top panel 11 of the flexible bag 10
or with all their waist features directed downwards towards the bottom
pane! of the flexible bag 10 or the flexible articles may be alternated. The
flexible bag 10 is preferably made from conventional flexible polymer
such as polyethylene or oriented polypropylene and the film caliper
ranges from 30 to 120 micrometres. The flexible bag 10 comprises a top
panel 11, a bottom panel, a front panel, a back panel and a pair of side
panels, which are all interconnected according to means known in the art.
Typically, the pre-made flexible bag 10 to be used for containing
the flexible articles is supplied either on wickets or on rolls, wickets being
preferred. The flexible bag 10 is sealed at its top panel 11 after
introduction of the flexible articles, leaving attached at least one flap 12,
which protrudes from the top panel 11 of the flexible bag 10. The
preferred embodiment comprises two flaps 12. These flaps 12 represent
excess trim material. A handle element 13 is then shaped from the flaps
12, and comprises a handle element perimeter 16. The handle element
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13 can combine both curved and straight portions as is depicted in Figure
2. Furthermore, the base of the handle element 13 can lie along a portion
of the top panel 11 as is visible in embodiments (1), (2) and (4) of Figure 2
or the base of the handle element 13 can run along the entire length of
the top panel 11 as is visible in embodiment (3) of Figure 2. The
formation of the handle element 13 is preferentially carried out during or
' shortly after the top panel 11 has been sealed. The key features of the
handle element 13 are the grip area 14, the grip area perimeter 15 and
the handle element perimeter 16. The grip area 14 can be formed on-
line by either cutting, punching or scoring out the desired shape, which is
suitable for gripping by the end user, namely the consumer. Alternatively,
grip holes can be cut, punched or scored out of the flaps 12. Several grip
holes, preferably three or four, may be present and they can also be pre-
made at the bag suppliers. The grip area perimeter 15 and the handle
element perimeter 16 follow the contours of the selected shapes for the
grip area 14 and the handle element 13, respectively.
Various sealing embodiments exist in order to reinforce the handle
element 13 and support the weight of the flexible bag 10. With a film
caliper ranging from 50 to 70 micrometres, the handle element 13 is
capable of sustaining bag loads ranging from 2.5 to 4 kilograms without
causing deformation or failure when being carried by the end user,
namely the consumer. it is preferred that the base of the handle element
13 run along the entire length of the top panel 11 (for example, refer to
embodiment (3) in Figure 2) such that the handle element 13 can better
support the bag load and lead to improved stability.
Figure 3 shows six different embodiments of sealing design
configurations that are suitable for the handle element 13. For each of the
embodiments described below, the base of the handle element 13
comprises a seal 17, which is either the complete seal 17 or a portion of
the seal 17 arising from the closure of the top panel 11 of the flexible bag
. 10. In the first embodiment, a seal 17 runs along the handle element
perimeter 16. In the second embodiment, the flaps 12 are sealed
together in the entire area of the handle element 13 except for the grip
area 14. In the third embodiment, the flaps 12 are further reinforced at
the handle element perimeter 16. In fact, the third embodiment comprises
the first embodiment and further comprises seals 17 that are located in
the corners lying closest to the seal 17 of the base of the handle element
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13 and the seal 17 running along the side of the handle element
perimeter i 6. It is feasible to place approximately one to three seals 17
per corner, the form of the seals 17 being either straight or curved. The
fourth embodiment comprises the first embodiment plus a seal 17
surrounding the grip area perimeter 15. The sea! 17 is preferably located
a distance ranging from 5 to 25 millimetres from the grip area perimeter
15 and typically the seal 17 follows the contours of the shape selected for
the grip area 14. The fifth embodiment similarly comprises the first
embodiment plus a seal 17 abutting the entire grip area perimeter 15.
The sixth embodiment, similar to the third embodiment, further comprises
reinforcements at the handle element perimeter 16. More specifically, the
sixth embodiment comprises both the first and fifth embodiments plus
diagonal seals 17 that extend from a location on the seal 17 running
along the outermost part of the handle element perimeter 16 to a location
on the seal 17 of the base of the handle element 13. The seals 17 in all
cases preferably range from three to four millimetres in width although any
width is possible.
The sealing can be performed using conventional heat sealing
techniques or alternatively, techniques such as ultrasound, crimping or
pressure banding can be employed. Heat sealing techniques tend to
weaken the flaps 12 in the immediate vicinity of the sealed area due to
the concentration of heat along the seal 17. In contrast, the other
techniques rely less on heat and more on pressure and thus do not
weaken adversely the flaps 12. It is also possible to vary the sealing
pattern. Rather than having a single line comprising the sealing pattern,
which is typical of the current heat sealing techniques, a pattern with
alternating bonded zones and unbonded zones can be formed. The
sealing pattern can comprise crosses, dashed lines, v-shapes, u-shapes,
inverted shapes, to cite but a few of the many possibilities existing. The
effect of the pattern results in an improved distribution of heat over a wider
area and consequently, a stronger supporting film around the seals 17.
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GLOSSARY
Flexible bag
1 1 Top panel
12 Flap
13 Handle element
14 Grip area
Grip area perimeter
1 fi Handle element perimeter
17 Seal
