Note: Descriptions are shown in the official language in which they were submitted.
CASE 50558 2 ~ 7 ~
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POUC~ ~AVING MEANE~ TO FACILI~ATE TEAR INIq~IATION
B~ckqrou~d o f the Invention
Field of the Invention
The invention relates to packaging, and more
particularly to a pouch having means to facilitate unaided
manual tear initiation.
Description of Related Art
Laminated films are commonly used in the
packaging art for hermetic pouches for perishables. The
films are generally maintained in rolls or webs and fed
into apparatus in which the pouches are generated in a
form, fill and seal operation. Strength and toughness are
required of the pouches to withstand the stress and wear
experienced during the form, fill and seal operation and
subsequent handling. Barrier properties are also required.
The materials chosen for the various layers of the
laminated films include polymeric films of, e.g., nylon,
polyester, or polyethylene, and/or metal foils composed of,
e.g., aluminum. Labels may be printed on a surface which
is at the interface of two layers after lamination to avoid
exposure of the labels to environmental wear fact~rs while
also avoiding contact between the product and the label.
The need for strength and toughness creates a
problem in that pouches which have the requisite strength
and toughness are often difficult for the consumer to open
without the use of scissors or other utensils, absent the
provision of means integral with the pouch to facilitate
tear initiation. In the past, one approach to the problem
has been to provide one or more V-shaped notches along one
or more edges of the pouch. Another approach has involved
providing one or more slits along an edge, extending
perpendicularly inward from the edge, as illustrated in
U.S. Patent No. 4,898,280. A third approach has been to
form a plurality of very small, shallow cut , or scratches
along the entire length of each of one or more edges Gf the
laminated film, as described in U.S. Patent No. 4,543,279.
A fourth approach has been to subject one layer to a
surface roughening treatment prior to lamination, as
described in U.S. Patent No. 4,778,058, such that one or
more edges of the package are weakened along their entire
lengths.
There remains a continuing need for improved
means to facilitate unaided manual tear initiation in
pouches for food products.
~Gary of the ~nvention
In accordance with the invention, there is
provided a pouch having a sealed edge portion which is
weakened in a predetermined area to facilitate tear
initiation. The weakened area i~ confined to a minor
portion of a seal area extending along one side edge of the
pouch so that the pouch may readily be opened by tearing
inward from the edge through the weakened area. The
remainder of the seal area is resistant to such tearing to
avoid accidental tear initiation at undesired locations.
Each of the walls of the pouch ls preferably of laminated
construction, having at least one barrier layer. The
weakened area i8 prefera~ly made susceptible to tearing by
provision of a plurality of discontinuities in at least one
layer of at least one of the walls, with at least one
barrier layer in each wall remaining intact. In one
embodiment of the invention, two weakened areas are
provided opposite one another on upper portions of the side
edges of the pouch, in proximity to the upper edge of the
pouch, whereby the top of the pouch may be torn off from
either side. The pouch may have a reclosable closure
extending arross its width between its side edges beneath
the weakened areas. The reclosable closure may comprise a
pair of complementary, interengageable zipper strips, or
may in the alternative comprise a bendable metal strip
6egment se~ured to one of the walls.
Brief Descrlptlon of t~e Draw~n~
FIG. 1 iB a plan view of a blank for forming a
pouch in accordance with the invention.
3 8
FIG. 2 is a fragmentary sectional Yiew of a
weakened area of the bla~k of FIG. 1.
FIG. 3 is a perspective view of a pouch in
alccordance with a first embodiment of the invention.
FIG. 4 is a fragmentary plan view of a pouch in
alccordance with a second embodiment of the invention.
PIG. 5 is a ~ectional view of the pouch of
FIG. 4, taken substantially along line 5-5 in FIG. 4.
FIG. 6 is a plan view of a pouch in accordance
with FIG. 4, shown in a reclosed configuration.
FIG. 7 is a fragmentary plan view of a pouch in
accordance with an embodiment of the invention.
FIG. 8 is a ~ectional view taken substantially
along line 8-8 in FIG. 7.
FIG. 9 is a perspective view of a pouch in
accordance with FIGS. 7 and 8, shown after opening.
FIG. 10 is a plan view of the pouch of FIGS. 7-9,
shown in reclosed configuration.
Det~ile~ De~cription Or P~eferred Bmbo~ment~
Referring to F~G. 3, the invention i8 preferably
embodied in a pouch 10 comprising a pair of generally
rectangular walls 12 heat sealed to one another about their
respective peripheries to define a generally rectangular
peripheral seal area 11 and an enclosed interior 13 between
said walls. The pouch 10 may be used for consumer
packaging of a food product such as shredded cheese, or for
various other packaging purpose~. The seal area in the
illustrated embodiment has side portions 14 extending along
opposite sides of the pouch, and upper and lower end seal
portions 16 and 18 respectively, extending along the
respective top and bottom edges of the package.
In accordance with the invention, each of the
side portions 14 of the peripheral seal area 11 has a
weakened area 20 extending inward from the side edge 22
adjacent the upper end of the pouch. Each weakened area 20
is confined to a minor portion of its respective side ~eal
portion 14 of the peripheral seal area so that the pouch
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may readily be opened by tearing inward from the side edge
22 through the weakened area 20, whereas the remainder of
the side portion 14 of the peripheral seal area 11 is
resistent to such tearing. ~he location of the areas of
weakness 20 adjacent the upper end of the pouch enables the
upper end seal portion 16 to be torn off while leaving the
remainder of the pouch substantially intact to contain the
food product without spillage when the pouch is maintained
in an upright position~ Means 34 may be provided to
facilitate tearing along a straight line across the top of
the pouch. The means 34 to facilitate tearing may take the
form of a line of weakness, such as a perforation or ~core
line, or in the alternative may simply comprise indicia
such as a printed serie6 of line segments to provide a
visual guide. A punched circular hole 35 is provided in
the upper seal area to enable the pou~h to be conveniently
supported on a display hanger. The hole is located so that
a portion of the upper seal area remains intact beneath the
hole to maintain hermeticity.
As shown in FIG. 2, each of the walls 12 of the
package i8 prefer~bly of laminated film construction,
comprising at least two layers 24 and 26, of which at least
one layer 26 is a barrier layer. The film may include
polymeric layers of, e.g., nylon, polyester, or
polyethylene, and/or metal foils co~posed of, e.g.,
aluminum. The weakened area 20 is defined by a plurality
of discontinuities 28 in at least one layer of at least one
of the walls. The discontinuities 28 may be random
scratches of varying depth, or may be punctures which
extend entirely through one of the layers. To maintain
hermeticity for the pouch, each of the walls may have at
least one barrier layer left intact, free of the
discontinuities.
As an alternative to maintain hermeticity for the
pouch, the areas of weakness 20 may be confined to outer
portions of the side seal areas 14, with non-weakened
regions of the peripheral seal area 11 disposed between the
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weakened area 20 and the pouch interior 13. This
arrangement enables employment of weakening techniques
which penetrate all layers of the wall material, without
loss of hermeticity.
The embodiment of FIG. 3 i5 particularly 6uitable
for pouches in which reclosability is not needed. In the
0mbodiments of FIGS. 4-6 and 7-10, the pouch includes a
reclosable closure extending between the side edges
immediately beneath the weakened areas, but is otherwise
substantially similar to the pouch of FIG. 3, and
accordingly the same reference numerals used in FIG. 3 are
used to denote like elements in FIGS. 4-6 and 7-lO.
In the embodiment of FIGS. 4-6, the reclosable
closure comprises a bendable metal strip segment 30 cecured
to one of the walls. The bendable metal strip segment 30
may be of the type described and illustrated in U.S. Patent
No. 4,898,280, the d~sclosure of which is incorporated
herewith by reference, and may be secured by a length of
sealing tape 31 to the pouch wall in the manner described
in Patent No. 4,898,280.
In the pouch of FIGS. 4-6, as in the pouch of
FIG. 3, access to the pouch i8 obtained initially by
tearing inward from a side edge 22 through one of the
weakened areas 20 and across the pouch to enable the upper
end seal area 16 of the pouch to be removed, leaving the
product contained in the remaining portion of the pouch.
After a portion of the product has been removed, the pouch
may then be reclosed by rolling the top of the remaining
lower portion of the pouch down around the bendable metal
strip segment 30, and subsequen`ly bending end portions 32
of the mstal 6trip ~egment inward to achieve the
configuration 6hown in FIG. 6. The metal strip ~egment 30
then retains the package in ~he closed position.
In the embodiment illu6trated in FIGS.7-10, there
is provided a reclosable closure 36 which comprises a pair
of complementary interengageable zipper ~trips 38 and 40.
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The pouch of FIGS. 7-10 is initially opened by tearing
inward from a side edge 22 through one of the weakened
areas 20 and across the pouch to enable the upper end seal
area 16 of the pouch to be removed, leaving intact a lower
portion including free edge areas 42 disposed above the
zipper profiles. ~he edge areas 42 are then manually
grasped and pulled apart to disengage the complementary
zipper profiles 38 and 40 from one another, and a product
such as shredded cheese 44 may then be dispensed as
illustrated in FIG. 9. After dispensing of the product,
the pouch may be resealed simply by application of pressure
to the opposite complementary zipper profiles 38 and 40
along their entire lengths. As illustrated in FIG. 10,
this may be accomplished manually 8i~ply by 6queezing the
profiles between the thumb 52 and forefinger 54 and sliding
the thumb and forefinger along the length of the zipper.
The pouch iE preferably formed, filled and sealed
on vertical form, fill, 6eal apparatus, using a web of
polymeric film material having the areas of weakness
preformed thereon. FIG. 1 illu6trates a blank 45 for a
pouch in accordance with the invention, 6hown as part o~ a
continuous web 58 having a series of like blanks thereon.
The blank comprises wall portions 46 having areas of
weakness 48 and 50 preformed thereon at the edges and at
the center, and has a prepunched hole 56 in each of its
wall portions 46. The blank may be formed into a pouch in
accordance with the invention by folding along its
longitudinal axis and sealing it about its periphery in a
vertical form, fill, 6eal operation. When the blank is
folded, the areas of weakness 48 at the edges of the blank
and the hole6 56 meet, and the central area of weakness 50
is folded in half.
In accordance with a first method of providing
the discontinuities which facilitate tear initiation at thQ
areas of weakness, a studded wheel $~ applied to the web of
material to be used as one of the layers in the wall~ of
the finished pouch, prior to lamination of the layers. The
2 ~ S~
discontinuities of predetermined size. In accordance with
a second method, the areas of weakness may be formed after
forming, filling and sealinq the pouch by a studded wheel
similar to that described above, or by an abrasive
implement which abrades one or both surfaces of the
peripheral seal area in the desired region 22. In the
latter case, the areas of weakness are limited to outer
portions of the peripheral seal area so that the inner
portion of the seal area remains intact to ensure that
hermeticity is maintained.
From the foregoing it will be appreciated that
the invention provides a novel and improved pouch. The
invention is not limited to the embodiments described
hereinabove, nor to any particular embodiments, but is
particularly pointed out in the following claims.