Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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A RESEALABLE BAG FOR FILLING WITH FOOD
PRODUCT(S) AND METHOD
Background of the Invention
The present invention relates generally to the
field of reclosable bags and more specifically to
reclosable bags that use or incorporate tamper evident,
hermetic seal, and reclosable fastener assemblies or
mechanisms of the slider, zipper, or press-to-close type.
The present invention is particularly concerned with a
reclosable bag that may be filled with a food product at
a factory or food processing plant and then sealed to
protect the food product until such time as a customer
purchases the reclosable bag and opens it to access the
food product within.
Reclosable, typically flexible, containers are well
known in the art. Such containers normally comprise a
bag-like structure made from a folded web of material,
like thermoplastic film. These types of containers may
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also include reclosable zipper structures, as well as
interlocking male and female zipper elements fused,
extruded, or attached to the bag sidewalls.
Alternatively, the reclosable zipper structures,
mechanisms, or assemblies may also be identified as
slider closure systems, i.e., a closure system for slider
bags and form, fill and seal technology that contain two
tracks that can be interlocked and a separate part (a
slider) that rides on the tracks and is used to open
and/or close the tracks. The bag-like structure is
created when the thermoplastic film is folded, sealed,
and severed along its exposed edges. ....a
Reclosable bags are a great convenience to the
consumer. This is especially true where the food product
or material contained within the bag is of a type that
may not all be consumed at once, for example, shredded
cheese, sliced cheese, cheese, processed cheese, deli
meats, snack foods, vegetables, fruits, sweets, etc. A
problem with these types of bags is achieving a design in
which the food product is hermetically sealed against
oxygen, atmospheric intrusion or transmission, bacteria,
molds, and/or other sources of contamination, while also
providing features that help to disclose to the consumer
evidence of tampering without substantially interfering
with the ease of use of the bag.
In addressing this problem it is also desired to
achieve a design that is easy to manufacture and may be
used in combination with known types of packaging
machinery that use form, fill, and seal technology such
as Horizontal Form Fill and Seal (HFFS) machines or
Vertical Form Fill and Seal (VFFS) machines. It is also
desired to achieve a design that may optionally be used
in combination with Horizontal Flow Wrapper (HFW)
machines; e.g., J-WRAP machines presently available from
Jones Automation Company, Inc. of Beloit, Wisconsin.
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Tamper evident packaging may also require the use
of 'several pieces of film, which must then be connected
to'each other. This can make manufacturing of the
reclosable bag more complicated.
Gusseted style packages are additionally greatly
convenient to the consumer. Gusseted style packages
allow the package to stand upright due to their wider
base. This is true when it is desirable to stand a
package upright by itself. Further, the wider base of
the gusseted style package enables them to hold a greater
volume of product than a conventional four-sided seal
package of similar dimensions. The challenge has been to
combine the convenience of a zippered packaged in one
gusseted, reclosable bag.
With a "press to close" type zipper, the gusset
style package is typically. formed with the gusset at the
bottom and the zipper at.the top. This type of package
is filled through the opened zipper. Several problems
have arisen during production and filling of this type
package. For example, in the package making process, it
is necessary for the "press to close" zipper to be closed
(i.e. the male and female profiles need to be engaged),
when the zipper profiles are fused together at the side
seal. If the male and female profiles are not engaged,
they are subject to misalignment. If they are mis-
aligned at the side seal station, the resulting package
will have a zipper that does not close completely,
specifically adjacent' to the side seal, and a leaky
package results. Furthermore, after the side seal is
added, the usually simple process of opening the zipper
for filling using a stationary blade to plow the zipper
open, is no longer a reasonable option. Rather, the
zipper must be opened, by either pulling the sides of the
package that the zipper is attached to apart, or by
holding the sides securely while a plunger lowers into
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the upper portion of the package, forcing the zipper
open. Regardless of the method chosen, an unacceptable
percentage of unopened packages or damaged zippers
results.
An additional problem encountered by usual top
filling of the zippered, gusseted bag, is product waste
and contamination of zipper profiles. As a solution to
this problem, some filling processes lower a fill tube
into the package and past the zipper profiles area in an
attempt to protect the profiles from the product. This
technique reduces profile contamination, but does not
eliminate it. This is because clearance must be
maintained between the fill tube and the package walls to
ensure consistency of tube insertion and to provide an
exit passage for the air of the package that the product
is, displacing. In the stream of air exiting the package
to make room for the product, some product is inevitably
included, and profile contamination results.
A further problem associated with traditional top
filling of zippered, gusseted packages occurs when the
zipper is closed after the package has been filled with
product. The usual method forces the zipper closed by
applying force to both sides of the zipper and in a
direction tangent to the sides of the package. This
process may not consistently close the zipper and those
that do close may have product pushed into the zipper
profiles.
Gusseted packages using a slider type zipper
encounter additional filling problems. In filling a
package of this type, the slider portion of the zipper
must be slid from one side of the package to the other in
order to open the profiles. Once the package is filled,
the sliding of the slider portion must be reversed to
close the top. This process is difficult and expensive,
rendering top filling through slider type zippered
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packages to be commercially impractical.
The closest gusseted package references are believed
to be U.S. Patent No. 5,938,337 issued on 17 August 1999,
U.S. Patent No. 5,529,394 issued on 25 June 1996, and
U.S. Patent No. 5,417,040 issued on 23 May 1995.
Although these patents disclose advantageous methods,
they fail to fully utilize the benefits of a gusseted
type package. Namely, because of the wider base provided
in a gusseted bag, they are able to hold a greater volume
than conventional four sided seal packages of the same
height and width. The above-mentioned patents provide
methods for filling the gusseted bag from the gusset side
of the package and opposite the closure mechanism.
However, when a gusseted bag is filled from the bottom,
gusseted side, product stacks upward in the package
similarly to filling a conventional four sided package..
The result is the inability to fully utilize the added
volume benefit that the gusset provides.
It is one of the objectives of the present
invention to provide a reclosable bag that may be
manufactured using known packaging machinery. As
previously, noted, such known machinery includes HFFS
machines, VFFS machines, and HFW machines. Additionally,
as will be apparent to a person of skill in the art after
reading the present disclosure contained herein
thermoform type machines like the one disclosed in US
Patent No. 4,240,241 could also be used to practice the
present invention disclosed herein, after appropriate
modification as the disclosure herein will make apparent.
It is also an objective to perform the
manufacturing task using only one piece of parent film in
combination with a reclosable zipper assembly.
Further, it is an objective of the invention to
provide the manufacturer with the option of including
some or all the features of tamper resistance or
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evidence, hermetic seal, and ease of use in the
redlosable bag that is produced.
Another objective, especially with slider or zipper
type structures or sliding type zippers or fasteners is
ease of use. While a sliding type zipper structure is
itself relatively easy to use, the bag structures include
sidewalls or fin portions that extend up past the sliding
type zipper structure. This interferes with the
consumer's access to the food, makes it difficult to see
the zipper structure, and also makes it more difficult to
easily operate the zipper mechanism. This is especially
true if the person opening and closing the bag is
disabled, has arthritis, or another aliment, which limits
the manual dexterity of that person.
Additionally, increased ease of access to the food
product is an objective because the larger the zipper
structure arid its associated elements the smaller the
opening left to the consumer to access the food product.
It is a further objective to provide a reclosable
gusseted package that may be side filled with product.
It is another objective to provide a reclosable
gusseted package that may be side filled and avoid zipper
profile contamination.
It is another objective to provide a reclosable,
gusseted package that may be side filled to ensure
optimal volumetric filling of the gusseted portion.
It is one of the objectives of the present
invention to provide a gusseted reclosable bag that may
be manufactured using known packaging machinery, such
known machinery includes HFFS machines.
The present invention is believed to address these
and other objectives by the unique and simple structures
and methods disclosed herein.
Summary of the Invention
The present invention may generally be described as
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a -'reclosable bag for filling with at least one food
product. The reclosable bag includes at least one sheet
of'web material. The sheet of web material has at least
two areas of structural weakness and at least one fold
structure located between and defined by the two areas of
structural weakness. The reclosable bag includes an
opening located generally opposite the fold structure.
(Please note that fold structure as used in the
specification and claims herein is to be interpreted as
broadly as possible and should include not only
'-' structures that are a fold but also any structure that
has the same or similar characteristics to a fold even
though said structure may be formed by non-folding means
or methods such as the result of joining or fusing the
edges of two or more sheets of film.) In addition, the
reclosable bag includes a sliding fastener structure
having a skirt structure of web. material extending
therefrom and located within the fold structure. The
skirt structure or skirt material may be either integral
to the slider fastener structure or' it may be coupled,
e.g., sealed or adhered, to the slider fastener
structure. The skirt structure includes a distal margin
that is coupled to the sheet of web material at a
location between the areas of structural weakness and the
opening. The web material of the reclosable fastener
structure extending past the areas of structural weakness
so that the reclosable fastener structure is located
within the fold structure. The reclosable bag is capable
of being filled with at least one food product through
the opening.
The reclosable bag structure of the present
invention may optionally include other features. For
example, but not by way of limitation, the skirt may
include an outside surface and an inside surface. The
distal margin is located on the outside surface. The
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inside surface may include a predetermined area having a
releasable adhesive material. This allows for the option
of having a peelable seal, which may be used to aid in
making the reclosable bag initially hermetic and may also
add another reclosable/resealable feature to the bag.
(Please note that the terms reclosable, resealable, and
releasable, in addition to their normal meaning, are used
herein, interchangeably, to describe a closed or sealed
opening that may be re-opened at a predetermined time to
aid in providing access to at least a portion of the
contents of the bag, and then closed or sealed to allow
the remaining contents to be stored in the bag for later
use and/or provide evidence of tampering.)
Additionally, and more typically, the web material
of the reclosable bag is substantially comprised of a
predetermined portion of a. roll of a parent. film
material. The predetermined. portion having predetermined
dimensions from which a reclosable bag of predetermined
dimensions may be constructed. The parent film material
may be manufactured to a specification which determines
the shape and location of the areas of structural
weakness and which makes the areas of structural weakness
an integral part of the parent film. Presently, it is
believed to be commercially preferred to do so.
Alternatively, the areas of structural weakness could be
applied to the parent film at a predetermined step of the
construction or manufacturing process of the resealable
bag.
Further, the areas of structural weakness may
extend intermittently, continuously, and linearly, non-
linearly, or in some other predetermined pattern across
a predetermined dimension of the sheet of web material.
The predetermined dimension where the area of structural
weakness is located may be either the length or the width
of the reclosable bag, which is usually rectangular in
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shape, depending on whether or not it is desired to use
the long edge or side of the bag or the short edge or
side'of the bag with the slider closure system. Use of
the long edge of the bag provides for a larger opening
and thus enhances the ease of access to the food material
or other materials contained within the reclosable bag.
The term structural weakness is generally used to
describe that area of the reclosable bag that is
intentionally designed to be easily torn by the consumer
to provide for evidence of tampering and to allow for
easy exposure of the zipper mechanism or assembly.
Nonetheless, it should be understood that use of the term
structural weakness should include, without limiting its
meaning, structures such as perforation, scores,
microperforations, and multiple laminate materials which
.include a layer having an area of material or materials
which are specifically designed to be easily torn.
Accordingly, it should be understood that the areas of
structural weakness are intentionally designed to create
a predetermined tear path, which may or may not be
hermetic.
Also, opening of the bag may be facilitated by the
application of a tear strip (e.g., tear tape or tear
string) along a predetermined surface or surfaces of the
parent film. The tear strip may or may not be used in
combination with a predetermined area of structural
weakness.
Alternatively, the present invention may be
described as a reclosable bag for filling with at least
one food product and comprising at least one sheet of a
web material. The sheet of web material includes a first
area of structural weakness and a second area of
structural weakness. (Alternatively, the areas of
structural weakness may be tear areas or areas having a
propensity to tear in a predetermined direction.) The
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sheet of web material including at least one fold
structure, located between and defined by the first and
second areas of structural weakness, and a fill opening.
The sheet of web material further comprising a first
panel coupled to the fold structure at the first area of
structural weakness and a second panel coupled to the
fold structure at the second area of structural weakness.
A reclosable fastener structure including a male track
structure and a female track structure. The male track
structure including a first fin structure of web material
extending therefrom and the female track structure
including a second fin structure of web material
extending therefrom. Each fin structure including a
predetermined coupling portion. The coupling portion of
the first fin structure being coupled to the first panel
and the coupling portion of the second fin structure
being coupled to the second: panel. (please note that the
seal, when it is formed, may be adjacent or near but
should not be on the area of structural weakness). The
reclosable fastener structure extending past the areas of
structural weakness and into the fold structure. The
areas of structural weakness being located below the
reclosable fastener structure. The alternative
reclosable bags are also capable of being filled with at
least one food product through the fill opening, which is
subsequently sealed.
The present invention allows the fold structure to
be easily removed from the reclosable bag. More
importantly the present invention allows the consumer to
substantially expose the reclosable fastener structure so
that it is easily accessible and the consumer does not
have to be impeded by bag sidewalls or bag fin portions
that extend up past the zipper structure. Finally, the
present invention accomplishes this using but not limited
to substantially one piece of film material.
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Alternatively, the present invention may be
described as a reclosable bag for filling with at least
one'food product. The reclosable bag may include at
least one sheet of web material, at least one tear tape
structure, at least one fold structure, and an opening
located generally opposite the fold structure. A
reclosable fastener structure including at least one
integral skirt structure of skirt web material extending
therefrom. The integral skirt structure including at
least one distal margin. The distal margin being coupled
to the web material at, at least one location between the
tear tape structure and the opening. The reclosable
fastener structure extending past the tear tape structure
and into the fold structure. The reclosable bag capable
of being filled with at least one food product.
Additionally, the reclosable bag for filling with
at least one food product, may also be described as a.
reclosable bag including at least one sheet of web
material having at least one fold structure presenting at
least two sidewall structures having inside surfaces, and
an opening located generally opposite the fold structure.
A reclosable fastener structure including an integral
skirt structure comprising a web material extending
therefrom and including opposed distal margin structures.
The web material of the integral skirt structure being
sealed to the inside surfaces of the sidewall structures
at a plurality of predetermined sealing areas. The
reclosable bag may also include a barrier web material
extending between and coupled to the distal margin
structures.
The barrier web material of the alternative bag may
alternatively extend between and be coupled to the
sidewall structures. Alternatively, the barrier web
material may also be coupled to predetermined sealing
areas by at least one peelable seal. Alternatively, the
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baK'rier web material may include at least one area of
structural weakness that extends through it along a
direction generally parallel to the predetermined sealing
areas.
Alternatively, the reclosable bag for filling with
at least one food product of the present invention may
include at least one sheet of web material having at
least one predetermined tear area, at least one fold
structure, and an opening located generally opposite the
fold structure. A reclosable fastener structure
including at least one integral skirt structure of skirt
web material extending therefrom. The integral skirt
structure including at least one distal margin. The
distal margin being coupled to the web material at, at
least one location between the tear area and the opening.
The reclosable fastener structure extending past the
tear area and into the fold structure. The reclosable
bag capable of being filled with at least one food
product.
This alternative reclosable bag structure may
further include at least one piece of a header material
located in a predetermined area of the fold structure.
The header material may include at least one edge
structure adjacent the tear area. The reclosable bag of
this alternative structure may further include at least
one tear tape structure coupled to the web material and
adjacent to the tear area.
Alternatively, the present invention may be
described as a reclosable bag for filling with at least
one food product. The reclosable bag may include at
least one sheet of web material, at least one tear tape
structure, at least one fold structure, and an opening.
A reclosable fastener structure including at least one
integral skirt structure of skirt web material extending
therefrom. The integral skirt structure including at
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least one distal margin. The distal margin being coupled
to the web material at, at least one location between the
tear tape structure and the opening. The reclosable
fastener structure extending past the tear tape structure
and around and over the fold structure. The reclosable
bag capable of being filled with at least one food
product.
Additionally, the reclosable bag for filling with
at least one food product, may also be described as a
reclosable bag including at least one sheet of web
material having at least one fold structure, and an
opening. A rec]osable fastener structure including an
integral skirt structure comprising a web material
extending therefrom and including opposed distal margin
structures. The web material of the integral skirt
structure being sealed to the outside surfaces of the
sidewall structures at a plurality. of predetermined
sealing areas. The inside surface of the reclosable bag
may also include a predetermined area having a releasable
adhesive material. This allows for the option of having
a peelable seal, which may be used to aid in making the
bag initially hermetic and may also add another
reclosable/resealable feature to the bag.
Additionally, the present invention may be
described as a method of construction using known form-
fill-and-seal machinery including but not limited to
HFFS, VFFS, and HFW machines. The steps of the method of
construction include 1. Folding the sheet of web
material along a predetermined folding area located
between the areas of structural weakness to form the fold
structure. 2. Inserting the reclosable fastener into
the fold structure. 3. Coupling the distal margin of
the integral skirt structure to the web material. 4.
Sealing the web material along at least two predetermined
linear areas located generally perpendicular to the fold
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structure. 5. Filling the reclosable bag with at least
one food product through an opening. 6. Sealing the
opening. Please note that in an HFW application it is
presently believed that the step four should occur last.
The method may also include a step of inserting
either a tear tape or a tear string at least prior to
step four. Further, a header strip could also be
introduced prior to step four.
Alternatively, the web material may be slit along
the fold line and the reclosable fastener assembly
inserted and sealed to result in an exposed zipper
structure assembly at one end of the bag. ~..
Also, alternatively, if the reclosable bag is
designed to have a gusset opposite the zipper opening
then the fill opening may be sealed and the bag may be
filled with product through the zipper opening.
Alternatively, the present invention may generally
be described as a gusseted, reclosable bag for filling
with at least one food product. The gusseted, reclosable
bag includes at least one sheet of web material. The
sheet of web material has at least two areas of
structural weakness, a gusseted portion, at least one
fold structure and an opening located generally between
the fold structure and the gusseted portion.
In addition, the reclosable bag includes a sliding
fastener structure having a skirt structure of web
material extending therefrom. The skirt structure or
skirt material may be either integral to the slider
fastener structure or it may be coupled, e.g., sealed or
adhered, to the slider fastener structure. The skirt
structure includes a distal margin that is coupled to the
sheet of web material at a location between the fold and
the opening. The reclosable bag is capable of being
filled with at least one food product through a fill
opening located between the skirt structure and the
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gusseted portion.
A backing or barrier strip structure is inserted
between and extending below the zipper skirts along the
side fill opening. The backing or barrier strip
structure may be made out of any suitable material but is
preferably two-ply and composed of a laminate film such
as Curwood's 7182 barrier film. One side of the barrier
strip structure to be used in the present invention is
nylon, or any other suitable material such as
polypropylene, which will not bond to the parent film.
The opposite side of the barrier strip structure may be
provided with a sealant such as polyethylene,
polyethylene blend, or a polyethylene co-extrusion. The
sealant side is sealed or tacked to the inside surface of
the top (or front side) zipper skirt prior to insertion
into an upper fold (i.e. fold structure). Once inserted
into the upper fold, the front side of each zipper skirt
is sealed to the parent film. The parent film then
passes over folding boards to form a bottom gusset. The
remaining unsealed edge of parent film extends upward to
meet the other edge located at zipper skirt. After
filling with product, the final sealing bar seals the
parent film to the zipper skirt and a portion of the
barrier strip structure to make a hermetic package. With
the barrier strip structure inserted between and
extending below the zipper skirts, the zipper skirts will
not seal to each other and the nylon side.of the barrier
strip structure will not seal to the opposite inside.
surface of the parent film.
The gusseted, reclosable bag structure of the
present invention may optionally include other features.
For example, but not by way of limitation, the skirt may
include an outside surface and an inside surface. The
distal margin is located on the outside surface. The
inside surface may include a predetermined area having a
CA 02640953 2008-09-19
releasable adhesive material. This allows for the option
of having a peelable seal, which may be used to aid in
making the reclosable bag initially hermetic and may also
add another reclosable/resealable feature to the bag.
Alternatively, if the reclosable bag is designed to
have a gusset opposite the zipper opening, the bag may be
filled with product through a fill opening located
between the zipper skirt and the gusseted portion.
Alternatively, the present invention may be
described as a gusseted, reclosable bag for side filling
with at least one food product and comprising at least
one sheet of a web material. The sheet of web material
includes a first area of structural weakness and a second
area of structural weakness. (Alternatively, the areas of
structural weakness may be tear areas or areas having a
propensity to tear. in a predetermined direction.) The
sheet of web material including at. least one -fold
structure, located between and defined by the first and
second areas of structural weakness, a fill opening, a
backing or barrier strip structure, and a gusseted
portion. A reclosable fastener structure including a
male track structure and a female track structure. The
male track structure including a first fin or skirt
structure of web material extending therefrom and the
female track structure including a second fin or skirt
structure of web material extending therefrom. Each fin
structure including a predetermined coupling portion.
(Please note that the seal, when it is formed, may be
adjacent or near but should not be on the area of
structural weakness). The reclosable fastener structure
extending past the areas of structural weakness and into
the fold structure. The areas of structural weakness
being located below the reclosable fastener structure.
The backing or barrier strip structure is inserted
between and extending below the fin or skirt structures
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along the side fill opening. As in the previous
embodiment, one side of the barrier strip structure to be
used is nylon, or any other suitable material such as
polypropylene, which will not bond to the parent film.
The opposite side of the barrier strip structure may be
provided with a sealant such as polyethylene,
polyethylene blend, or a polyethylene co-'extrusion. The
sealant side of the backing or barrier strip of this
alternative embodiment may be sealed or tacked to the
inside surface of the top (or front side) zipper skirt
prior to insertion into an upper fold (i.e. fold
structure). Once inserted into the upper fold, the front
side of each zipper skirt is sealed to the parent film,
as discussed with regard to the reclosable gusseted bag
with sliding fastener structure. Alternatively, an anti-
seal agent may be brush applied to the inside surface of
the zipper. skirt prior to insertion into an upper. fold.
Alternatively, the present invention may be
described as a gusseted, reclosable bag for side filling
with at least one food product. The'reclosable bag may
include at least one sheet of web material, at least one
fold structure, at least one gusset structure, a side
fill opening having a backing or barrier strip structure,
located generally between the fold structure and the
gusset structure. A reclosable fastener structure
including at least one integral skirt structure of skirt
web material extending therefrom.' The integral skirt
structure including at least one distal margin. The
distal margin being coupled to the web material at, at
least one location between the fold structure and the
opening. The reclosable bag capable of being filled with
at least one food product.
This alternative reclosable bag structure may
further include at least one piece of a header material
located in a predetermined area of the fold structure.
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The header material may include at least one edge
structure adjacent the tear area.
Additionally, the present invention may be
described as a method of construction using known form-
fill-and-seal machinery including but not limited to
HFFS, VFFS, and HFW machines. The steps of the method of
construction include 1. Placing a backing or barrier
strip structure in registration with the side seal. 2.
Punching out the strip in the area that is both in the
side seal and adjacent to the skirt of the zipper to
which the backing or barrier strip will be attached. 3.
Attaching the backing or barrier strip to the inside face
of one of the skirts of a zipper track with sealant side
of the strip facing the inside surface of the skirt. 4.
Heat sealing a portion of the remaining strip adjacent
the zipper skirt to the zipper skirt. 5. Folding the
sheet of web material along a'predetermined folding. area
located between areas of structural weakness to form a
fold structure. 6. Inserting the reclosable fastener
and attached backing strip structure into the fold
structure. 7. Attaching the zipper track to the web in
a location relative to the areas of structural weakness
by heat sealing the web to the skirt portions of the
zipper track. 8. Positioning the edge of the web such
that it is attached to, but not covering the entire
portion of, the skirt having the barrier strip attached.
9. Passing the remaining web across folding boards such
that a gusset is formed at the bottom of the package.
10. Folding the other edge of web material upward to the
remaining exposed zipper skirt having the backing or
barrier strip attached, and adjacent to the first edge of
the web. 11. Sealing the web material along at least
two predetermined linear areas located generally
perpendicular to the fold structure. 12. Filling the
reclosable bag with at least one food product through the
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side opening. 13. Sealing the opening.
The method may also include a step of introducing a
header strip prior to step ten.
Alternatively, the process and structure of the present
invention could include a reclosable fastener assembly having
two skirts or flaps of web material. The first skirt could
be coupled or sealed to the parent film prior to folding the
parent film. (Additionally, the first skirt could be tack or
partially sealed prior to folding and then subsequently a full
seal applied in the HFFS, VFFS, or HFW machine) . After
folding the parent film the second skirt or flap would be
sealed to the film sidewall located opposite the sidewall to
which the first skirt is sealed or coupled. Construction of
the bag could then be completed as disclosed herein.
In summary, a reclosable bag for filling with at least
one food product is provided, said reclosable bag comprising:
at least one sheet of web material including at least two
areas of structural weakness, having at least one fold
structure located between and defined by said two areas of
structural weakness, and an opening located generally opposite
said fold structure;
a reclosable fastener structure including a skirt
structure of skirt web material extending therefrom;
said skirt structure including a distal margin;
said distal margin being coupled to said web material at,
at least one location between said areas of structural
weakness and said opening;
said reclosable fastener structure extending past said
areas of structural weakness and into said fold structure;
said reclosable bag capable of being filled with at least
one food product through said opening; and
wherein said areas of structural weakness extend nonlinearly
across a predetermined dimension of said sheet of said web
material.
19
CA 02640953 2011-05-17
A second reclosable bag for filling with at least one
food product is also provided, said reclosable bag
comprising:
at least one sheet of web material having a propensity
to tear along at least two predetermined tear areas;
having at least one fold structure located between and
defined by said two tear areas, and an opening located
generally opposite said fold structure;
a reclosable fastener structure including a skirt
structure of skirt web material extending therefrom;
said skirt structure including a distal margin;
said distal margin being coupled to said web material
at, at least one location between said two tear areas and
said opening;
said reclosable fastener structure extending past said
two tear areas and into said fold structure;
said reclosable bag capable of being filled with at
least one food product through said opening; and
wherein said tear areas extend nonlinearly across a
predetermined dimension of said sheet of said web material.
Description of the Drawings
Figure 1 is a top plan view of a predetermined portion
of parent film comprising a sheet of web material including
at least two areas of structural weakness.
Figure 2 is an edge elevational view of a portion of
the sheet of web material of Figure 1 and shows the
location of the areas of structural weakness.
Figure 3 is a side elevational view of the fold
structure of a reclosable bag of the present invention
showing the position of the slider or zipper structure in
the fold structure relative to the predetermined position
of the areas of structural weakness.
Figure 4 is a perspective view of the embodiment shown
in Figure 3.
Figure 5 is a front plan view of a first embodiment of
19a
CA 02640953 2011-05-17
the present invention.
Figure 6 is a front plan view of an alternative to the
first embodiment of the present invention disclosing sealed
track mass 23b.
Figure 7 is a front plan view of an alternative
20
30
19b
CA 02640953 2008-09-19
embodiment of the present invention.
Figure 8 is a view taken from line 8--8 of Figures
and 6.
Figure 9 is an alternative to the embodiment of the
5 present invention shown in Figure 8.
Figure 10 is another alternative to the embodiment
shown in Figure 8.
Figure 11 is an alternative to the embodiment shown
in Figure 10 wherein a peal seal tape with a releasable
adhesive located on one side of the tape is used.
Figure 12 is a view from line 12-12 of Figure-11,
the header material 15 that is shown, along with other
structures, is optional.
Figure 13 is another alternative to the embodiment
shown in Figure 8.
Figure 14 is a front plan. view of another
alternative embodiment of the present invention.
Figure 15 is a view taken from line 15--15 of
Figure 14.
Figure 16 is an alternative to the embodiment of
the present invention shown in Figure 15.
Figure 17 is another alternative to the embodiment
shown in Figure 15.
Figure 18 is another alternative to the embodiment
shown in Figure 15.
Figure 19 is a front plan view of an alternative
embodiment of the present invention.
Figure 20 is a view from line 20--20 of Figure 19.
Figure 21 is a plan view of an alternative
embodiment of the present invention illustrating various
features of the invention including die cutting of the
track mass of the zipper assembly and the use of a tear
structure like a tear tape or a tear string.
Figure 22 is a view from line 22--22 of Figure 21.
Figure 23 is a view of an alternative to the
CA 02640953 2008-09-19
r
1
embodiment shown in Figure 22 wherein tear tape is
applied to both the inside and outside surface of the
bag.
Figure 24 is a cut-away view of an alternative to
the embodiment shown in Figure 22 wherein the tear tape
includes a tear bead.
Figure 25 is a perspective view.of the embodiment
shown in Figure 24.
Figure 26 is a cut-away view of a predetermined
portion of the embodiment shown in Figure 24 illustrating
the tear tape and tear bead's relationship to the film
and the area of structural weakness created as a result
of the presence of the tear bead.
Figure 27 is an alternative embodiment to the
structure disclosed in Figure 22.
Figure 28 is a plan view of an alternative
embodiment of the present invention illustrating various
features of the invention including the use of an
optional header strip and the use of an optional opening
to assist in removal of the hood and exposure of the
zipper assembly.
Figure 29 is a view from line 29--29 of Figure 28.
Figure 30 is a schematic diagram showing the
components of another alternative embodiment of the
present invention being fed into a machine suitable for
adaptation to perform the process and make at least one
of the products disclosed herein before the plow
structure of the machine.
Figure 31 is a schematic diagram showing the
components of another alternative embodiment of the
present invention being fed into a machine suitable for
adaptation to perform the process and make at least one
of the products disclosed herein before the plow
structure of the machine..
Figure 32 is a schematic top plan view illustrating
21
CA 02640953 2008-09-19
I
at least one method by which the components of the
alternative embodiment disclosed in Figure 30 are
introduced prior to the plow mechanism of the form fill
ana seal machine.
Figure 33 is a schematic top plan view illustrating
at least one method by which the components of the
alternative embodiment disclosed in Figure 31 are
introduced prior to the plow mechanism.of the form fill
and seal machine.
Figure 34 is a perspective view generally showing
the general relationship of the components for making the
various embodiments disclosed herein. Specifically, the
embodiment having the peel seal tape is disclosed
although after review of this disclosure it will be
apparent to a person of ordinary skill in the art how the
machinery may be modified to. produce the various
embodiments disclosed, described, and.claimed herein.
Figure 35 is side elevational schematic view
illustrating the steps of construction of the alternative
embodiment disclosed in Figure 30 subsequent to folding
the parent film on the plow structure.
Figure 36 is side elevational schematic view
illustrating the steps of construction of the alternative
embodiment disclosed in Figure 31 subsequent to folding
the parent film on the plow structure.
Figure 37 is. an alternative embodiment of the
present invention illustrating various features of.the
invention including the use of tear string and a diamond
shaped opening as opposed to a circular opening for
assisting in the removal of the hood and exposing the
zipper assembly.
Figure 38 is a schematic diagram showing the
components of another alternative embodiment of the
present invention being fed into a machine suitable for
adaptation to perform the process and make the product
22
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t
1
I
disclosed herein, wherein either a tear string or the
zipper assembly are introduced to the parent film after
the' plow.
Figure 39 is a side elevational schematic view
illustrating the steps of construction of the alternative
embodiment disclosed in Figure 38 wherein the tear string
or slider or zipper assembly is introduced after the plow
structure.
Figure 40 is a front plan view of an alternative
embodiment of the present invention.
Figure 40a is a front plan view of the alternative
embodiment of Figure 40, but showing a peel seal area.
Figure 41 is a view taken from line 41 - 41 of
Figure 40a and showing the reclosable fastener structure
extending over the fold structure and peel seal.
Figure 41a is an enlarged view of the structure
shown in Figure 41 and showing the position of the slider
or zipper structure over the fold structure relative to
the predetermined position of the areas of structural
weakness.
Figure 42 is a front plan view of an alternative
embodiment of the present invention.
Figure 43 is a view taken from line 43-43 of Figure
42 and showing a gusset portion, a slider fastener, and
barrier strip and fill opening therebetween.
Figure 44 is a view similar to that shown in Figure
43 but with the gusset portion open and showing a
flattened bottom.
Figure 45 is a side elevational view of the fold
structure of the reclosable bag shown in Figures 42 - 44
showing the position of the slider or zipper structure in
the fold structure relative to the barrier strip and fill
opening, and showing side 36 in phantom in position for
filling through side opening, and side 36 in solid line
illustrating the closed opening after filling.
23
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I
Figure 45a is a partially cut-away perspective view
of the alternative embodiment shown in Figure 45.
Figure 46 is a schematic diagram illustrating at
least one method by which the components of the
alternative embodiment disclosed in Figures 42 - 45 are
assembled.
Figure 47 is a schematic top plan view illustrating
at least one method by which the components of the
alternative embodiment disclosed in Figures 42-45 are
introduced prior to the plow mechanism of the form fill
and seal machine.
Figure 48 is a side elevational schematic view
illustrating the steps of construction of the alternative
embodiment disclosed in Figure 42-45 subsequent to
folding the parent film on the plow structure and tucking
board.
Figure 49 is a front plan, view of an alternative
embodiment of the present invention.
Figure 50 is a view taken from line 50-50 of Figure
49 and showing a gusset portion, press-to-close fastener
with barrier strip, and fill opening between the gusset
portion and fastener.
Figure 51 is a view similar to that shown in Figure
50 but with the gusset portion open and showing a
flattened bottom.
Figure 52 is a side elevational. view of the fold
structure of the reclosable bag shown in Figures 49 51
showing the position of the. press-to-close zipper
structure in the fold structure relative to the barrier
strip and fill opening, and showing side 36 in phantom
while in position for filling through the fill opening
and side 36 in solid line illustrating the closed and
sealed, post-fill position.
Figure 53 is a schematic diagram illustrating at
least one method by which the components of the
24
CA 02640953 2008-09-19
s
embodiment disclosed'in Figures 49-52 are assembled.
Figure 54 is a schematic top plan view illustrating
at 'least one method by which the components of the
embodiment disclosed in Figures 49-52 are introduced
prior to the plow mechanism of the form fill and seal
machine.
Figure 54a is a cross sectional view taken along
lines 54a-54a of Figure 54 and showing the press-to-close
zipper structure and backing strip.
Figure 55 is a side elevational schematic view
illustrating the steps of construction of the alternative
embodiment disclosed in Figures 49-52 subsequent to
folding the parent film on the plow structure and tucking
board.
Figure 55a is an enlarged partial view of the area
referred. generally as 55a in Figure 55.
Figure 56 is a perspective view generally showing
the general relationship of the components for making the
gusseted embodiments shown in Figures 42-55a.
Figure 57 is a perspective view generally showing
the relationship of the components for making a prior art
gusseted*bag.
Figure 58 is a perspective view of a prior art, top
filled gusseted bag.
Figure 59 is a perspective view of a side fill
gusseted bag of the. present invention and showing a
slider type zipper and a backing strip.
Detailed Description
Although the disclosure hereof is detailed and
exact to enable those skilled in the art to practice the
invention, the physical embodiments herein disclosed
merely exemplify the invention which may be embodied in
other specific structures or methods. While the
preferred embodiment has been described, the details may
be changed without departing from the invention, which is
CA 02640953 2008-09-19
defined by the claims.
The present invention is both a method and a
structure resulting from the method. The present
invention generally relates to reclosable plastic bags
100 and, more particularly, to a reclosable plastic bags
100 having a slider or zipper assembly 20, which
cooperates with a tamper-evident feature. The tamper-
evident feature may also be a hermetic seal feature. The
method of the present invention, while unique and fully
described herein, may be used on known machinery such as,
by way of illustration and not by way of limitation, the
rpm 100 packaging machine manufactured by Klockner
Packaging Machinery of Sarasota, 'Florida, U.S.A. The
modifications necessary to the machinery used to practice
the present invention will be apparent to a person of
ordinary skill in the art after reading this disclosure.
Reclosable plastic bags using. various zippers and
sealing mechanisms are well known. However, the
advantages of the present invention are believed not to
be apparent from the known zippers and sealing mechanism
of the prior art. The zipper assembly 20 typically
includes a zipper structure 20a and an integral skirt 16.
In the present invention, the skirt 16 is bonded to the
parent film 10 at a predetermined seal location 14. See
Figure 3.
Referring to Figures 1-5, the method and structure
of the present invention may begin to be generally
described. Referring to Figure 1 a predetermined portion
of the parent film 10 is illustrated. The parent film
10, at predetermined locations, is structurally weakened,
e.g., by the use of presently known laser scoring
technology.
Referring to Figure 2, an elevational edge view of
the parent film 10 including the score lines 12 may be
seen. The weakened area 12 may also be imperforate and
26
CA 02640953 2008-09-19
't .
r
hermetic. The weakened areas 12 define an integral tear
off portion or fold structure 11.
Referring to Figure 3, the film 10 is folded over,
as shown, to form the fold structure 11 and a zipper
assembly 20 is inserted. Weakened areas 12 are
preferably positioned below the zipper structure 20a so
that when fold structure or hood 11 is removed the zipper
structure 20a is exposed sufficiently above the resulting
fin structures 19 to allow the user access to the zipper
structure 20a. Zipper skirts 16 are shown bonded to the
film 10. However, it is presently believed preferable,
prior to insertion of the zipper assembly 20, that the
uncut ends 23 (see Figure 5) of each zipper assembly 20
be punched out or cut to form a radiused notch 22a, as
shown in Figure 7. The cut zipper assembly ends 22 are
sealed together (the sealed mass 22b of Figure 7) which
will later function to retain the contents of. the bag 100
such as food.
Referring back to Figure 3, the skirt(s) 16 remain
intact so that the zipper assembly 20 is kept continuous
for ease of handling. Once inserted the skirt(s) 16 of
the zipper assembly 20 is bonded to the inside surface
10a of the parent film 10 at seal location(s) 14.
Next sides 30 and 32 are sealed, along margin lOc
illustrated in Figures 5 or 7, using a known mechanism.
such as a heat-sealing bar of a form fill and seal
machine by advancing the folded film 10 to the heat
sealing bar portion of the machine used; creating a seal
30a across the length and width of margin loc. The
resulting bag 100 is then filled with a predetermined
foodstuff or other desired material through the opening
33 located, opposite the zipper assembly 20, at bottom
edge 34 shown in Figure 5 or 7. Then bottom edge 34 is
subsequently sealed, forming seal 34a.
This results in the zipper assembly 20 being
27
CA 02640953 2008-09-19
I
hermetically sealed within the tear off portion 11. Tear
off portion 11 is integral to the parent film 10.
Integral tear off portion 11 may be easily removed by
tearing along the score lines 12, leaving the zipper
structure 20a fully exposed and easily accessible for the
use desired.
The above noted process and mechanism may also be
performed so that the zipper assembly 20 is located along
one of the long sides 30 or 32 of the bag 100 rather than
the short side of the rectangle, which is defined by the
bag 100.
Referring to Figure 5, a second embodiment of the
present invention 1 is illustrated. As may be seen from
Figure 5 two bags 100 are shown prior to their being
separated along seam 101. This embodiment includes score
lines 12 laid out in an alternative pattern that includes
curve or arcuate :section 13 and tear notch 24. As'
further disclosed in Figure 7 the parent film 10 is
sealed at section 26 to either its opposing sides 35 and
36 or the structure of the zipper assembly 20. The tear
notch 24 provides a starting point for removing the fold
structure 11, which is located above the zipper assembly
20. The fold structure 11 being defined by the location
of the score lines 12. The score lines 12 extending
2S along curve 13 to a predetermined area below the zipper.
assembly 20 for substantially the entire width of the
reclosable bag 100 facilitating removal of the hood or
fold structure 11 and exposure of the zipper structure
20a. The embodiment of Figure 5 further including a
hermetic seal 40.
Referring now to Figure 8, a cross-sectional view
of the embodiment of Figure 7 may be seen. In
particular, the integral skirt 16, usually comprised of
two strips on pieces of plastic film or a one-piece unit
of continuous film, may be seen to have its outside
28
CA 02640953 2008-09-19
r
surface 19 sealed hermetically to the inside surfaces 36a
and 35a at respective hermetic seals 40a and 40.
Additionally, a peelable seal 50 is located at the bottom
of the skirt 16. Any standard commercially known
resealable adhesive 51 may be used to make the peel seal
50. The peel seal 50 may also be a hermetic seal 40b.
Referring now to Figure 9 an alternative to the
embodiment of Figure 8 is shown. In this embodiment the
zipper skirt 16 is heat sealed to the side panels 36 and
35 respectively of the parent film 10. The inside
surfaces 17 of the zipper skirt 16 are peelable sealed to
one another, using a known releasable adhesive 51, to
provide a releasable hermetic or gas tight seal 5o
therebetween. It should be noted that the terms
resealable adhesive or releasable adhesive as used herein
should be construed interchangeably as well as given
their common meaning.
Referring now to Figure 10 another alternative
embodiment of Figure 8 is shown. In this embodiment the
parent film 10 is sealed along a predetermined portion 42
of inside surface 35a and 36a. A known releasable
adhesive 51 is used to form a peelable seal 50 between
inside surfaces 35a and 36a at predetermined portion 42.
US Patent No. 4,944,409 contains an example of such an
adhesive. Presently, CUREX brand grade 4482-0, supplied
by Curwood of Oshkosh, Wisconsin is considered an
acceptable adhesive for use with this embodiment of the
present invention.
Referring now to Figures 11 and 12 another
alternative embodiment is illustrated wherein the
peelable seal 50 is comprised of a peel seal tape 53
having a permanent sealant like a metallocene catalyzed
polyethylene located on one side and a releasable seal
material like the aforesaid CUREX brand material on the
other side (side 54).
29
CA 02640953 2008-09-19
{
r.
1
one possible method for achieving the structure of
Figure 11 and 12 is the use of a form fill and seal
machine system in which the peel seal tape 53 would be
tacked onto a predetermined location of the parent film
10 prior to the plow 200. (See Figures 31, 33, and 34
for a general illustration of the location of the plow
200 in relationship to the other components of a form
fill and seal machine. Please note with reference to
Figure 33 that it is presently believed preferable for
heat sealer bar 208 to be enlarged sufficiently so that
in addition to sealing the tear tape 120 is place it also
seals the permanent seal side of the peal seal tape 53 in +--~
place at the same time. Accordingly, while one sealer
bar 208 is believed preferable for these separate
functions multiple bars could be used, each having a
dedicated function or a combination of functions). After
the plow.200 the peelable.sealant.side 54 would be sealed
to the parent film 10 by heat sealer bars 55. - Use of
sealer bars 208 and 55 as disclosed herein allows
independent temperatures and pressures to be used for
each seal and it is believed that more consistent peel
seals will result.
Additionally, the zipper skirt 16 may be sealed in
place subsequent to the plow 200 by sealer bar 56 and the
header seal 206a may be made by sealer bar 57 as
illustrated generally in Figures 34 and 36.
Referring now to Figure 13 another alternative
embodiment of Figure 10 is shown. In this embodiment,
the zipper skirt 16 includes an elongated section 16a.
End 21 of elongated section 16a is positioned between
the inside surfaces 36a and 35a of the side panels 36 and
of the parent film 10. The elongated section 16a is
heat sealed to the parent film 10 on inside surface 35a
and peelable sealed using a known releasable adhesive 51
35 to inside surface 36a to form peel seal 50.
CA 02640953 2008-09-19
t.
Referring now to Figure 14 a third embodiment of
the'present invention is disclosed. Again, two bags 100
are shown prior to their being separated along seam 101.
The invention of the third embodiment is comprised of
parent film 10, which is used to form the bag 100 that is
to be filled. The bag 100 includes a first side seal 30,
a second side seal 32, and a fill opening 33. Side panel
35 forms the front side of the bag 100. The fill opening
33, after the bag 100 is formed and filled with a
predetermined type of food material, is heat sealed to
~-~ form bottom edge or seal 34. The bag 100 further
includes a fold structure 11, header 15, integral zipper
skirt 16, a zipper assembly 20 including a zipper
structure 20a, at least one hermetic seal 40, an unsealed
area 60, and a section 62 where the zipper skirt 16 and
the. ends 23 of the zipper assembly 20 are heat sealed
together (see sealed mass 23b in' Figure 14).prior to
their insertion between the front side 35 and the back
side 36 of the film 10. This forms sealed mass 23b. The
formation of sealed mass 23b may take place at sealer
216, which is illustrated in Figure 30.
Sealing zipper skirt (s) 16 to the parent film 10
forms the hermetic or gas tight seal 40. The zipper
skirts 16 may have a predetermined portion or portions
that extend past seal 40 and which may be held together
with a peel seal 50. See for example, Figure 15.
Since, within the unsealed area 60, the side panels
and 36 are not attached to the zipper assembly 20, the
hood structure 11 (which may be defined by the score
30 lines 12) may be easily removed to expose zipper
structure 20a. The sealed mass 23b provides for
containment of product when the peelable seal 50 is
opened.
Referring to Figure 15 a view from line 15--15 of
35 Figure 14 may be seen. This may be seen to be identical
31
CA 02640953 2008-09-19
1
to the embodiment of Figure 8, except as explained above
with reference to Figure 14.
Referring now to Figure 16 an alternative structure
to the one shown in Figure 15 may be seen. In this
alternative, the zipper skirt 16 is made of one piece of
material. It is heat sealed to the inside surfaces 35a
and 36a to form hermetic seals 40 and 40a. The skirt 16
is provided with a structural weakness 45 which extends
linearly and generally parallel to hermetic seals 40 and
40a along the zipper skirt 16. The structural weakness
45 is designed to fracture or tear relatively easily when
the customer opens the bag 100. =--=
Referring now to Figure 17, an alternative to the
embodiment shown in Figure 16 may be seen. In this
embodiment the zipper skirt 16 includes a barrier film
section 16b. The barrier film 16b is applied (preferably
by heat sealing although other methods. could be used,
e.g., Adhesive coupling, ultrasonic or high frequency
sealing technology) to the inside surface 16d of the
zipper skirt 16. The zipper skirt 16 is heat sealed
along a predetermined portion of its outside surface 16e
to parent film 10 to form a hermetic seal 40. The
barrier film section 16b is releasably sealed to the
inside surface 16d to form at least one peel type seal
50. Note that it is presently believed that section 16b
must have a surface 16c that is resistant to heat
sealing.
Referring now to Figure 18 an alternative to the
embodiment shown in Figure 17 may be seen. In this
embodiment barrier film section 16b is heat sealed to a
separate predetermined portion of the inside surfaces 35a
and 36a of the parent film 10. To form two additional
hermetic seals 40 located below the hermetic seals 40 of
the zipper skirt 16. The barrier film 16b is provided
with a structural weakness at 45 which extends linearly
32
CA 02640953 2008-09-19
f
I
and generally parallel to hermetic seals 40. The
structural weakness is designed to fracture or tear
relatively easily when the customer opens the bag 100.
Alternatively, the structure of Figure 17 could be
provided with a structural weakness 45 as described with
reference to Figure 18. In such a case peel seal 50
would be replaced with a permanent seal.
Referring to Figures 19 and 20, header strip 206,
located between the front side 35 and back side 36'of the
parent film material 10, of a predetermined size have
sufficient width to extend down to, preferably just
above, a tear line 132 (area of structural weakness).
The header strip 206 terminates at edge(s) 131. This
tear line 132 has the predetermined propensity to tear in
predetermined way. The extension of the header strip
material 206 extends down so.that it is adjacent to the
tear line 132. This facilitates tearing off the hood
structure 11 from the bag 100 along the tear line 132.
The optional tear notch 134 facilitates initiation of
the tear, the tear line 132 (the oriented parent film 10
or film 10 with the propensity to tear) directs the tear,
and the header material 206, which is bonded or sealed to
the front side 35 and back side 36 of the parent film 10,
controls the tear so that the zipper structure 20a is
consistently clear of the parent film material 10 after
the removal of the hood structure 11.
Alternatively, if the header material 206 is made
of an oriented polypropylene having at least one side
with a heat sealable sealant then the parent film 10
would not need to be oriented or have the tear line 132
or propensity to tear.. Presently, it is believed
preferable that if the header material 206 is made of an
oriented polypropylene then the oriented polypropylene
should have both its sides coated with a heat sealable
sealant. Also, alternatively,- a plurality of header
33
CA 02640953 2008-09-19
s Y
strips 206 could be used instead of a single integral
header strip 206. In either case, the parent film 10
would not necessarily need to be oriented or have a tear
line 132 or a propensity to tear.
Referring to Figures 21 and 22, at least one but
preferably two pieces of tear tape 120, located between
the front side 35 and back side 36 of the parent film
material 10 on film surfaces 35a and 36a, of a
predetermined size are bonded or sealed to the parent
film 10 of the hood structure 11 adjacent, preferably
just above, a tear line 132 (area of structural
weakness). This tear line 132 has the predetermined
propensity to tear in predetermined way. The tear tape
material 120 adjacent the tear line 132 facilitates
tearing off the hood structure 11 from the bag 100 along
the tear line.132 in a controlled manner. The optional
tear notch 134 facilitates initiation of the tear,.the
tear line 132 (the oriented parent film or film with the
propensity to tear) directs the tear, and the tear tape
120, which is bonded or sealed to the front side 35 and
back side 36 of the parent film 10,'controls the tear so
that the zipper structure 20a is consistently clear of
the parent film material 10 after the removal of the hood
structure 11. Alternatively, if the tear tape material
120 is made of an oriented polypropylene having at least
one side with a heat sealable sealant then the parent
film 10 would not necessarily need to be oriented or have
the tear line 132 or propensity to tear. .'
With respect to facilitating removal of hood or
fold 11 it should be understood that instead of score
lines 12 the parent film 10 may be weakened in
predetermined areas using other procedures as well,
including but not limited to scoring or the use of multi-
ply laminate film having a predetermined weakened area or
the addition of a tear assistance structure, e.g., Tear
34
CA 02640953 2008-09-19
tape 120 or tear string 120a. The tear assistance
structure may be added for use by itself or in
conjunction with a predetermined area of structural
weakness 12 to aid in the tearing of the film 10. See
Figures 28 and 29.
Referring to Figure 23 another alternative to the
embodiment disclosed in Figure 22 is disclosed. In this
embodiment tear tape 120 is applied to both the inside
surfaces 36a and 35a and the outside surfaces 36 and 35
of the bag 100. In this embodiment no score line or
weakening 132 is believed necessary (although such an
area of structural weakness could be used) since the tear
tape 120 located on both the inside and outside surfaces
of the bag 100 will act as an effective tear guide.
Referring to Figures 24, 25, and 26 another
alternative to the, embodiment shown in Figure 22 is
illustrated. In this embodiment..a modified tear tape
120b having a tear bead 120c is used.
As:;`Figures 24-26 illustrate, when the film 10 is
sealed to the tear tape 120b the bead 120c is depressed
into the film 10 creating an area of structural weakness
12 without requiring pre-scoring or other modification of
the parent film 10 prior to the application of the tear
tape 120b. This structure is believed beneficial because
the tear tape 120b is always in alignment with the area
of structural weakness 12.
Referring to Figure 27 another alternative. to the
embodiment disclosed in Figure 22 is disclosed. In this
embodiment tear tape 120 is applied to both the inside
surfaces 36a and 35a and the outside surfaces 36 and 35
of the bag 100. The tear tape 120 is applied to border
both sides of the score line or weakening 132. Since the
tear tape 120 is located on both sides of the score line
132 and on the inside and outside surfaces of the bag 100
a very consistent controlled or guided will be achieved.
CA 02640953 2008-09-19
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I
Tear tape 120 is interchangeable with tear string
120a. Accordingly, a tear string 120a could be
substituted for the tear tape 120. See, e.g., Figures 38
and 39. Preferably, the tear tape 120 or the tear string
120a used is made from a material, e.g., Thermoplastic
material, that is compatible with the film 10 and which
may be sealed, coupled, or bonded to the film 10. For
example, the tear tape 120 or tear string 120a may be
formed of polyethylene or may be encased in polyethylene.
It is understood in the art that a tear string, such as
tear string 120a, may have various cross-sectional
shapes, e.g., Round, square, triangular, etc., which may
be used to enhance its ability to tear the parent film
material 10.
In particular, referring to Figures 30, 32, and 35,
the process by which the alternative embodiment having
tear tape 120 is presently believed to be manufacturable
is illustrated using an rpm 100 machine. The parent film
10 is fed over a predetermined number of rollers and
toward the plow structure 200. The parent film 10 after
passing over dancer roller 203a is die punched by die 210
to present parallel openings 121. It is presently
believed that the film 10 must pass over the dancer
rollers 203a so that they are kept sufficiently taut thus
allowing openings 121 to be punched out accurately at
predetermined positions, by die 210, such that the
positions of the openings. 121 are always at the same or
a uniform distance from each other. In addition to the.
parent film 10 two rolls of tear tape 120 are fed over
the parent film 10 and in parallel alignment with the
parallel openings 121 such that the tear tape 120
preferably, but not necessarily, bisects each the
parallel opening 121. Tear string 120a could be
substituted for tear tape 120. See, e.g., Figures 38 and
39.
36
CA 02640953 2008-09-19
In addition, referring back to Figures 30, 32, and
35 optionally a header material 206 may be fed over the
parent film 10. Further, the zipper or slider assembly
20 is also fed over the parent film 10. Prior to being
fed over the parent film 10 the zipper assembly 20 has a
notch 22a die punched, by die 214 and heat sealed by
sealer 216, at a predetermined position that is also
designed to be in general alignment with the parallel
openings 121. Once the tear tape 120 is presented over
the parent film 10 but before it is passed over the plow
200 it passes over a tear tape sealer mechanism 208 so
that the tear tape 120 is sealed to the parent film 10.
Alternatively, the tear tape 120 could be tacked in place
and subsequently sealed to the parent film 10 either
before or after the plow 200.
The parallel openings 121 may be of any shape
although. circular is the shape,.that is presently
preferred. Diamond shaped cuts could be used to further
enhance initiation of the tear in the parent film 10.
See Figure 37.
Additionally, the notch 22a as generally
illustrated herein may be of an arcuate or radiused shape
but the notch 22a could also be made at a sharp angle
such as a 90 angle. See Figure 37. The sharper angle
is presently believed to add more stress to the structure
of the zipper assembly 20 and therefore a radiused
structure is presently considered to be preferred.
However, the present invention should not be interpreted
as being limited to solely a radiused notch 22a as
generally illustrated herein.
After the parent film 10 is folded the remaining
manufacturing process is carried out as generally
illustrated in Figure 35. The zipper skirts 16 are
sealed to the respective sides of the parent film 10 at
seal 14. The header strip 206, if used, is sealed to the
37
CA 02640953 2008-09-19
I
parent film 10 at seal 206a. The side seal 30a is made,
which also seals the perimeter or edge 121a of opening
121. (note, if no tear tape 120 or tear string 120a is
used then it is presently considered best to add a tear
notch 24 to the opening 121 to facilitate removal of the
hood 11.) An opening 123 is die punched in the package
100 to provide a point where the package 100 may be
easily hung for display purposes. The package 100 is
then cut along seam 101 from the V-fold portion of the
form fill and seal machine and transferred to the fill
and seal stations where fill opening 33 is opened and the
package 100 is filled and gas is flushed through the fill
opening 33. Opening 33 is then hermetically sealed at
seal 34a.
Alternatively, referring to Figure 38 and Figure 39
the zipper assembly 20 may be introduced subsequent to
the plow structure 200.. The parent filth 10, prior to
being fed over the rollers 202 is still die punched by
die 210 to present parallel openings 121. Also,
alternatively, the tear tape 120 or tear string 120a may
be feed over the parent film 10 and in parallel alignment
with the parallel openings 121 subsequent to the plow
200. See Figures 38 and 39. Again, the tear tape 120 or
tear string 120a preferably, but not necessarily, bisects
each parallel opening 121. Also, while Figure 39 shows
both the tear string 120a.and skirts 16 of the zipper
assembly 20 being introduced to the parent film 10
subsequent to the plow 200 and respectively sealed by.
sealer bars 208 and 209 it should be understood that
either the tear string 120a or the zipper assembly 20
could be introduced before the plow 200. For example,
the zipper assembly 20 could be introduced after the plow
200 and the tear string 120a prior to the plow 200.
Since tear tape 120 is interchangeable with the tear
string 120a it will be apparent to a person of ordinary
38
CA 02640953 2008-09-19
r
1
skill in the art reading this disclosure that the tear
tape 120 could also be introduced after the plow 200 and
used in essentially the same manner as the tear string
120a.
The openings 121 are provided, at a minimum, to
facilitate access to the tear tape 120 or the tear string
120a and to facilitate tearing and removal of the hood 11
to expose the zipper assembly 20.
Additionally, the present invention may be used in
combination with other VFFS and HFFS machines. The
= present invention could also be used with HFW machines.
However, in using either VFFS machines or HFFS machines
the method of the present invention is presently believed
to require post-compression (commonly called post-
squashing) of a predetermined portion of the track
structures 20b, with respect to the embodiment.. shown in
Figure 6. (sometimes also referred to as track. mass 20b,
herein) of the slider closure assembly 20 located within
a margin or line lob of the parent film 10 where a seal
30a, especially a hermetic seal, is desired.
Alternatively, the track mass 20b may have a pre-
compressed portion located with margin lob. Neither pre-
compression nor post-compression are believed to be
required where a notch, e.g., 22a of Figure 7, has been
punched out or cut from the zipper assembly 20. However,
if pre-compression is desired then this is accomplished
in the present invention at sealer 216. shown. in Figure
30. This is so that when, on either a HFFS or VFFS
machine, the track mass 20b (with the slider or zipper
structure 20a avoided) passes through the package side
seal zone portion of either the machine a consistent
hermetic seal 30a is produced by the application of the
heater bars of the machine used. As will be apparent to
a person of ordinary skill in the art from this
disclosure, if a notch, e.g., notch 22a of Figure 7, is
39
CA 02640953 2008-09-19
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-1
cut from the zipper assembly 20 then there is no
structure or mass for sealer 216 to pre-compress and
sealer 216 will then only provide seal 22b of the cut end
22, as shown in Figure 7.
In applications using HFW machines for the
manufacture of the embodiment shown in Figure 5, such as
Jones Automation Company machines, it is not believed
necessary to pre-compress, post-compress, or squash a
predetermined portion of the track mass 20b. HFW
machines have a rotary jaw assembly, which includes a
hinged side. The jaw assembly provides at least two
advantages, either of which, separately or in
combination, eliminates the need for pre-compression of
the track mass 20b. First, the jaw assembly provides a
1S relatively long time, longer than the time provided by
either VFFS or HFFS machines, for the application of heat
and pressure sufficient to form. the desired seal '30a.
Second, the portion of the track mass 20b that is
targeted to be fused or sealed (generally located within
the boundary of margin 10b) is placed or fed into the jaw
assembly so that it is placed toward and near the hinged
portion of the jaw assembly and thus maximum mechanical
advantage and force may be applied to the predetermined
portion of the track mass 20b.
If either the longer seal time or the mechanical
advantage of the jaw assembly of the HFW machine was not
available then,. referring to Figure' 6, since there is
generally insufficient room on an HFW machine to pre
compress the track mass 20b, the track mass 20b may be
pre-punched with a die at the predetermined location 22a
(where the seal 30a is also to be applied or created)
prior to insertion into the fold 11 of the parent film
10. Since the pre-punched area or notch 22a would be
synchronized to be in registration with the portion of
the folded parent film 10 that is to be sealed, less
CA 02640953 2008-09-19
energy (time, temperature, and/or pressure), due to the
reduced mass to be sealed is required to consistently
obtain the type of seal 30a desired. (note, pre-punching
rather than pre-compression could also be used with HFFS
or VFFS machines.)
Referring now to Figures 40, 40a, 41 and 41a, an
alternate embodiment of the present invention: may be
seen. The film 10 is folded over, as shown, to form the
fold structure 11, and a zipper assembly 20 is positioned
over the fold structure 11. Weakened areas 12 are
preferably positioned below the zipper structure 20a, so
that when the zipper structure 20a is in the open
position the fold structure 11 and its weakened areas 12
are exposed to allow the user access to the fold
structure 11. Seen particularly in Figure 41, the
overlaying zipper skirt-16, of the alternate embodiment,
may be viewed. Zipper. skirt 16 is usually comprised of
two strips of pieces of plastic film or a one-piece unit
of continuous film, and is seen to have its inside
surfaces 17 sealed hermetically to the outside surfaces
35b, 36b of the film 10 at respective hermetic seals 40c,
40d. The fold structure 11 is preferably designed to act
as an. imperforate hermetic barrier to protect the
contents of bag 100. Tearing the fold structure 11
allows the user access to the contents and also provides
visual evidence that the hermetic seal is broken. Seen
particularly in Figures 40a and 41, the inside surfaces
35a, 36a of the parent film 10 may also be peelably
sealed to one another, using a known releasable adhesive
51, to provide a releasable hermetic or gas tight seal 50
therebetween. The seal SO is located adjacent,
perferably just below, the weakened areas 12.
As best seen in Figures 40 and 40a, two bags 100 are
shown prior to their being separated along seam 101. The
alternate embodiment seen in these views is comprised of
41
CA 02640953 2008-09-19
parent film 10, which,is used to form the bag 100 to be
filled. The bag 100 further includes a header 15, and a
peg hole 15a, seen in this embodiment at the end opposite.
the fold 11. It is presently believed preferable, after
the folding and sealing of parent film 10 that the parent
film 10 be punched out to form a tear area 24a. The
parent film is then sealed around the perimeter of the
punched out tear area 24a and a tear notch 24 is added,
as seen in Figure 40. These steps are preferably
performed before the attachment of the zipper assembly 20
and zipper skirt(s) 16. Following this, the zipper
assembly 20 is positioned and bonded to the outside
surfaces 35b, 36b, of the parent film 10, and over the
fold 11. Alternately, the parent film 10 may be sealed
around the perimeter to include the sealed perimeter of
the punched out tear, area 24a,so that after the punching
step which forms tear area 24a, the sealed perimeter
remains. The tear notch 24 provides a starting point for
removing the fold structure 11, which is surrounded by
the zipper assembly 20 and attached zipper skirt 16.
Further, at least one piece of tear tape 120, located
between the front side 35 and back side 36 of the parent
film 10 on film surfaces 35a, 36a, of a predetermined
size may be bonded or sealed to the parent film 10 at the
fold 11. The tear tape 120 is located adjacent,
preferably just above, a tear line 132 (area of
structural weakness). This tear line 132 has the
predetermined propensity to tear in a predetermined way.
The tear tape material 120 adjacent the tear line 132
facilitates tearing off the fold structure 11 from the
bag 100. The aforementioned tear notch 24 facilitated
initiation of the tear.
Referring to Figures 41 and 41a, the skirt(s) 16
remain intact so that the zipper assembly 20 is kept
continuous for ease of handling. Once positioned over
42
CA 02640953 2008-09-19
,f Y
the punched fold structure 11, the skirt(s) 16 of the
zipper assembly 20 is bonded to the outside surfaces
35b,36b of the parent film 10 at seal location(s) 40c,
40d. Next, sides 30 and 32 are sealed, along margin 10c
illustrated in Figure 40, using a known mechanism such as
a heatsealing bar of a form fill and seal machine (as
described earlier in the present application).=by
advancing the film 10 to the heat sealing bar portion of
the machine to be used.
It will be apparent to the person of ordinary skill
in the art after reading this disclosure that the present
alternative embodiment shown in Figures 40, 40a, and 41,
41a may be manufactured using the methodology previously
disclosed herein with the necessary modifications, which
this specification makes apparent to a person of -skill in
the art.
With reference to Figures 42 - 45a; an alternative.
embodiment reclosable bag 100' including a gusseted
portion 310 and side fill opening 300 is shown.
The gusseted, reclosable bag 100' includes at least
one sheet of web material 10 having at least two areas of
structural weakness 12. The areas of structural weakness
12 may be micro perforations, scoring or any other
structural weakness that will allow facile tearing of the
web material 10. The weakened areas 12 define an
integral tear, off portion or fold structure 11. The
gusseted, reclosable bag 100' is further ,defined by a
gusseted portion 310 and a sealable fill opening 300.
The sealable fill opening 300 is located generally
between the fold structure 11 and gusseted portion 310.
A backing or barrier strip 320 is inserted between the
zipper skirts 16. The backing or barrier strip 320 is
preferably two-ply material and may be composed of
laminent film such as Curwood's 7182 barrier film. A
first or inner side 328, may be composed of Nylon,
43
CA 02640953 2008-09-19
I
polypropylene, or any other suitable material that will
not bond to the parent film 10 during sealing. A second
or 'outer side 329 of the strip 320 may be provided with
a sealant, such as a polyethylene, polyethylene blend, or
a polyethylene co-extrusion. The backing or barrier
strip 320 is preferably notched at 326 and 326a (best
seen in Figure 47) to allow proper sealing of side seal
30a. A zipper assembly 20 having attached zipper skirts
16 is inserted in the fold structure 11. When the zipper
assembly 20 and skirt(s) 16 are. bonded to the inside
surface 36a of parent film 10 at 14, the inner resistant
side 328 of strip 320 prevents the skirt(s) 16 from
sealing together along their respective inner surface 17,
seen particularly in Figure 45. The skirts 16 are
bonded at 14 to the inside surface of the parent film 10.
As may be seen from Figure 42, two bags 100' are
shown prior to their being separated along seam 101.
This embodiment includes score lines 12 laid out in a
pattern that includes a tear notch 24. The tear notch 24
provides a starting point for removing the fold structure
11, which is located above the zipper assembly 20. The
parent film 10 is sealed at section 26 to either its
opposing sides 35 and 36 or the structure of the zipper
assembly 20. For ease of illustration, it is to be noted
that seal 30a extends across notches 326, 326a in strip
320 and area 26a refers to the general area of the
hermetic side seal 30a adjacent the notches 326, 326a.
The fold structure being defined by the location of the
score lines 12. The score lines 12 extend below the
zipper assembly 20 for substantially the entire width of
the reclosable gusseted bag 100', facilitating removal of
the fold structure 11 and exposure of the zipper
structure 20a. The embodiment of Figure 42 further
includes a sealable fill opening 300 located below the
zipper assembly and above the bottom gusset 310.
44
i
CA 02640953 2008-09-19
s
I
Referring now to Figures 43 and 44, a cross-
sectional view of the embodiment of Figure 42 may be
seen. In particular, the backing or barrier strip 320 is
seen with an upper portion 324 thereof attached to the
inside surface 17 of the zipper skirt 16. As may be
further seen, a lower portion 322 of the barrier strip
320 is attached to the inside surface 32a of the bag 100'
at a point just below the fill opening 300. As
illustrated particularly in Figure 44, the lower portion
322 is seen prior to attachment to inside surface 32a,
with the fill opening 300 in the open position. For
illustration purposes, when opening 300 is shown in the
closed position the web edges 400 are seen as not
completely abutting. It is to be understood that while
it is preferred that the edges 400 abut, it is within the
scope of the present invention to include a closed
opening 300 wherein the web edges 400 are'not completely
abutted.
Referring to Figure 45, the film 10 is folded over,
as shown to form the fold structure 11 and a zipper
assembly 20 is inserted. Weakened areas 12 are
preferably positioned below the zipper structure 20a so
that when the fold structure 11 is removed, the zipper
structure 20a is exposed sufficiently above the resulting
fin structures 19 to allow the user access to the zipper
structure 20a. Zipper skirts 16 are shown bonded to the
film 10. However, it is presently believed preferable,
prior to insertion of the zipper assembly 20, that the.
uncut ends (not seen in these views) of each zipper
assembly 20 be punched out or cut to form a radiused
notch 22a, as shown in Figure 42. As seen in Figure 45,
an upper portion 324 of a backing or barrier strip 320 is
attached to the inside surface 17 of one of the zipper
skirts 16. A lower portion 322 of the strip 320 extends
beyond the distal margin 342 of the zipper skirt 16 and
CA 02640953 2008-09-19
1 i
is bonded to the inside surface 36a of side 36. It is
presently believed preferable, prior to attachment to the
zipper skirt 16, that the backing or barrier strip 320 be
punched out or cut to form notch 326 (seen in Figure 47).
As may be further seen in Figure 47, barrier strip 320
is further punched prior to insertion into fold structure
11, to form notch 326a, also in register with side seal
30a. Notches 326 and 326a are positioned to be in
register with radiused notch 22a of zipper assembly 20,
all of which are positioned to be in register with side
seal 30a, seen in Figures 42 and 48. Consecutive notches
326, 326a in barrier strip 320 alleviate the presence of
barrier strip 320 at side seal 30a, thus facilitating a
hermetic seal at area 26a (best seen in Figure 42). The
hermetic seal is obtained by sealing inside opposing
surfaces. 35a, 36a at 26a and 30a. The inside surface 10a
of parent film.10 is simultaneously 'sealed to the zipper
skirts 16 at area 14, as seen in Figure 45, and
simultaneously, inside surfaces 17 of skirts 16 (Figure
45) are sealed to each other in the notched out areas 326
and 326a at 26a, where the barrier strip is not present
(seen best in Figure 42).
As illustrated in Figures 45 and 47, the skirt(s)
16 remain intact so that the zipper assembly 20 is kept
continuous for ease of handling. Once inserted, the
skirt(s) of the zipper, assembly 20 is bonded to the
inside surface 10a of the parent film 10 at seal
location(s) 14.
Referring to Figures 46, 47, and 48, the process by
which the alternative embodiment gusseted, side fill bag
100' (seen in Figures 42 - 45) is presently believed to
be manufacturable is illustrated using an rpm 100
machine. The parent film 10 is fed over a predetermined
number of rollers and toward the trapezoidal plow
structure 200a. In addition to the parent film 10, the
46
CA 02640953 2008-09-19
7
zipper assembly 20 and backing strip 320 are fed over the
parent film 10. it is presently believed that the zipper
assembly 20 and backing strip 320 must pass over the
dancer rollers 203a so that they are kept sufficiently
taut thus allowing notches 22a, 326, and 326a to be
punched out accurately at predetermined positions such
that the notches 22a and 326 will be in register with
each other when the backing strip 320 is inserted between
zipper skirts 16. Prior to being fed over the parent
film 10, the zipper assembly 20 has a notch 22a die
punched,'by die 214' and heat sealed by sealer 216', at
a predetermined position at seal 22b that is also
designed to be in general alignment with the notch 326 in
strip 320, formed by die 21411 and 326a formed by die
214'. It is to be noted that notch 326 is preferably
formed such that the distal margin 342 of skirt 16
extends into the notch.326. This configuration, allows
notch 326a to be formed by die 214' with minimal chance
of skirt 16 being inadvertently notched by die 214'. Die
214' simultaneously forms notches 326a and 22a. The
parent film 10 is folded over the zipper assembly 20 to
form the fold structure 11. Before the parent film 10 is
passed over the trapezoidal plow 200a it passes over a
zipper sealer mechanism 216 whereby the zipper skirts 16
are sealed to the parent film 10 at the inside surfaces
35a, 36a of opposing sides 35, 36 respectively. Unlike
prior embodiments, no blade between the skirts 16 is
needed during sealing since, as seen in Figure 45, the
inner side 328 of strip 320 will not seal to the inside
surface 17 of opposite zipper skirt 16. Further, gusset
holes 344 are die punched by die 344a at a predetermined
position designed to be in general alignment with side
seal 30a. The gusset holes 344 allow gusset folds to be
attached to each other at side seal 30a thereby adding
rigidity to the gusset portion 310 of the gusseted bag
47
CA 02640953 2008-09-19
1
104'. This added rigidity enables the gusseted bag 100'
to.-stand up by itself when placed on a flat surface such
as, a table or refrigerator shelf (not seen in these
views). Further, with reference to the prior art
gusseted bags 460 seen in Figure 57, additional seals 470
may be included for additional rigidity and containment
as would be desired with liquid products.
In addition, referring to Figures 46 and 47,
optionally a header material 206 may be fed over the
parent film 10. The header strip 206, if used, is sealed
to the parent film 10 at seal 206a, seen particularly in
Figure 47. As seen in Figure 46, seal 206a is formed by
heat sealer 216. Heat sealer 216 simultaneously seals
the zipper skirt(a) 16 to the parent film 10 at 14. The
parent film 10, attached zipper assembly20, and strip 320
are passed over roller 350. After the parent film 10 is
folded and the zipper assembly. 20' is inserted, the
remaining manufacturing process is carried out as
generally illustrated in Figure 48. The parent film 10
and attached zipper assembly 20 passes over a trapezoidal
folding board or plow 200a. The folding step leaves a
flat bottom prior to the parent film 10 being passed over
a tucking board 334. The tucking board 334 reverse folds
the previously formed flat bottom of the parent film 10
into a gusset 310. The side seal 30a is made. It is to
be noted that the barrier strip 320 preferably marginally
enters the area of side seal 30a at seal area 26a.
Notches 326 and 326a preferably remove a majority of the
barrier strip 320 in the seal 30a area to provide
hermetic seal 30a. Although it is preferred that the
barrier strip 320 minimally enter the side seal 30a area
at seal area 26a, it is within the province of the
present invention to provide a barrier strip 320 which
ends before, at, or beyond the side seal 30a area.
Further, it is to be understood that the present
48
CA 02640953 2008-09-19
I
invention may be practiced using a barrier strip 320
having longitudinally-spaced sealable areas whereby the
notches 326 and 326a are not necessary and the sealable
areas are arranged to be in alignment with the seal area
30a. Tear notch 24 is added to facilitate removal of the
fold 11. An opening 123 is die punched in the package
100' to provide a point where the package 100' may be
easily hung for display purposes. The package 100' is
then cut along seam 101 from the bag making portion of
the form fill and seal machine and transferred to the
fill and seal stations where the side fill opening 300 is
opened and the package 100' is filled through side fill
opening 300. The opening 300, seen in Figure 48, is then
hermetically sealed at seal 340, as seen in Figure 48.
The presence of the backing or barrier strip 320 permits ;
the seal 340 to be formed while the.inside surfaces 17 of
zipper skirts .16 are not sealed 'to one another (see
Figure 45). As previously described with reference to
Figures 42-45, the inner side 328 of strip 320 will not
seal to inside surface 35a or zipper skirt 16 during
sealing, thus permitting a seal without the need for a
blade between the skirts 16.
Referring now to Figures 49 - 52, an alternative
embodiment gusseted, side fill bag 100' is illustrated.
As may be seen, a press-to-close zipper assembly 20'
having lower skirt(s) 16 and upper skirts 16a may be
inserted in the fold structure 11. As in the embodiment
shown in Figures 42-45a, the gusseted, reclosable bag.
100' with press-to-close zipper assembly 20' seen in
Figures 49-52 includes at least one sheet of web material
10 having at least two areas of structural weakness 12.
The weakened areas 12 define an integral tear off
portion or fold structure 11. The gusseted, reclosable
bag 100' is further defined by a gusseted portion 310 and
a sealable fill opening 300 which is located between the
49
CA 02640953 2008-09-19
fold structure 11 and gusseted portion 310. As best seen
in: Figure 52, the press-to-close zipper assembly 20'
typically includes a male track structure 330 and a
female track structure 331. The male track structure 330
and the female track structure 331 each include an upper
zipper skirt 16a of web material extending therefrom and
a lower zipper skirt 16 extending therefrom. Each zipper
skirt 16, 16a includes a predetermined coupling area
arranged to be sealed to the parent film 10 at sealing
location 14.
As may be further seen in Figure 52, the zipper
skirt(s) 16 is heat sealed to the inside surface 35a, 35b
of side panels, 35 and 36 respectively, of the parent
film 10. A backing or barrier strip 320 is located
between, and extends below the zipper skirts 16. As
discussed with reference to the embodiment shown in
Figures 42 - 45, the backing or-barrier strip 320 is.
preferably two-ply and composed of a laminate film such
as Curwood's 7182 barrier film. As such, the strip
includes a first side 328 and a second side 329. The
first side 328 is preferably composed of Nylon,
polypropylene, or any other substance known in the art
that will not bond to the zipper skirt 16 or parent film
10 during heat sealing. The second side 329 may be
provided with a sealant, such as a polyethylene,
polyethylene blend, or a polyethylene co-extrusion. The
second or sealant side 329 of the strip.320 is sealed or,
tacked to the inside surface 17 of a zipper skirt 16,
prior to insertion in the fold structure'll at a location
adjacent the sealable side fill opening 300 at seal 335.
The inner, resistant side 328 of strip 320 prevents the
skirt(s) 16 from sealing together along their respective
inner surface 17 during sealing of the side fill opening
300. The backing or barrier strip 320 is preferably
notched at 326 and 326a, as seen in Figure 54, to allow
CA 02640953 2008-09-19
$
IA
proper sealing of side seal 30a.
As may be seen from Figure 49, two bags 100' having
press-to-close zipper assembly 20' are shown prior to
their being separated along seam 101. The score lines 12
are seen to be laid out in a portion that includes a tear
notch 24. The tear notch 24 provides a starting point
for removing the fold structure 11, which is located
above the press-to-close zipper assembly 20'. The fold
structure 11 being defined by the location of the score
lines 12. The parent film 10 is sealed at area 26a to
either its opposing sides 35 and 36 or the structure of
the press-to-close zipper assembly 20'. For ease of
illustration, it is noted that the seal 30a extends down
across notches 326, 326a in strip 320. Reference numeral
1S 26a refers to this general area of hermetic side seal
30a. The embodiment seen in Figure 49 further includes
a sealable fill opening 300 located below the fold
structure 11 and above the bottom gusset 310.
Referring now to Figures 50 and 51, a cross
sectional view of the embodiment of- Figure 49 may be
seen. The backing or barrier strip 320 is particularly
seen, with the upper portion 324 thereof attached to the
inside surface 17 of zipper skirt 16. The lower portion
322 of the barrier strip 320 is attached to the inside
surface 36a of the parent film 10 at a point below the
fill opening 300. As illustrated particularly in Figure
51, the lower portion 322 is seen prior to attachment to
inside surface 36a, with the fill opening 300 in the open
position. For illustration purposes, when opening 300 is
shown in the closed position, as in Figure 52, for
example, web edges 400 are seen as not completely
abutting. It is to be understood that while it is
preferred that web edges 400 completely abut when opening
300 is in the closed and sealed position, it is within
the scope of the present invention to include a closed
S1
CA 02640953 2008-09-19
opening 300 having non-abutting web edges 400.
Referring now to Figures 53- 55a, the process by
which the alternative embodiment, gusseted, side fill bag
100' (seen in Figures 49-52) is illustrated. Seen
particularly in Figure 54, a press-to-close zipper
assembly 20' may be introduced prior to the trapezoidal
plow structure 200a. The parent film 10 is fed over a
predetermined number of rollers and toward the plow 200a.
The press-to-close zipper assembly 20' and backing strip
320 are fed over the parent film 10. It is presently
believed that the press-to-close zipper assembly 20' and
backing strip 320 must pass over the dancer rollers 203a
so that they are kept sufficiently taut to allow notches
326, and 326a to be punched out accurately at
predetermined positions such that the notches 326 and
326a will be in register with each other when the backing
strip 320 is inserted between zipper skirts.16. As seen
in Figure 54, notch 326 is punched out prior to insertion
of the strip 320 between skirt(s) 16, whereas notch 326a
is punched out prior to insertion of press-to-close
zipper assembly 20' into fold structure 11. It may be
further seen that notch 326 is preferably formed such
that the distal margin 342 of skirt 16 extends into the
notch 326. This configuration allows notch 326a to be
formed by die 214' while preventing skirt 16 from
inadvertent notching by die 214'. Die 214' punches notch
326. Figure 55a illustrates the position of notches 326,
326a relative the backing strip 320 and distal margin 342-
of zipper skirts 16. The press-to-close zipper assembly
20' is heat sealed by sealer 216 to strip 320 at seal
335.
The parent film 10 is folded over the press-to-
close zipper assembly 20' to form the fold structure 11.
As seen in Figure 53, prior to being passed over the
trapezoidal plow 200a, the parent film 10 it passes over
52
i
CA 02640953 2008-09-19
a zipper sealer mechanism 216 whereby the zipper skirts
16= are sealed to the parent film 10 at the inside
surfaces 35a, 35b of opposing sides 35, 36 respectively.
As is further seen in Figure 53, the press-to-close
zipper assembly 20' and backing strip 320 further passes
over a blade 450 which allows the skirts 16 and 16a to be
heat sealed to the web 10 while preventing the inner
surfaces 17 of the skirts 16, 16a from sealing together.
Further, gusset holes 344 are die punched by die 344a at
a predetermined position designed to be in general
alignment with side seal 30a. The gusset holes 344 allow
gusset folds to be attached to each other at side seal
30a thereby adding rigidity to the gusset portion 310 of
the gusseted bag 100'. This added rigidity enables the
gusseted bag 100' to stand up by itself when placed on a
flat surface, such as a table or refrigerator shelf (not
seen in these views).
Again referring to Figures 53 and 54, optionally a
header material 206 may be fed over the parent film 10.
The header strip 206, if used, is sealed to the parent
film 10 at seal 206a, seen particularly in Figure 54.
After the parent film 10 is folded and the press-to-close
zipper assembly 20' and strip 320 are inserted, the
remaining manufacturing process is carried out as
generally illustrated in Figure 55. The parent film 10
with attached press-to-close zipper assembly 20' and
strip 320 passes over a trapezoidal folding'boardor plow
200a. The folding step leaves a flat bottom prior to the,
parent film 10 being passed over a tucking board 334. As
is also illustrated in the manufacturing steps of the
gusseted bag 100' seen-in Figures 42-45, the tucking
board 334 reverse folds the previously formed flat bottom
of the parent film 10 into a gusset 310. The side seal
30a is made and tear notch 24 is added to facilitate
removal of the fold structure 11. It may be seen that
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CA 02640953 2008-09-19
_ 9 7
I
the barrier strip 320 preferably marginally enters the
area of side seal 30a at seal area 26a. A majority of
the strip 320 is removed by notches 326 and 326a, thereby
allowing a hermetic seal to be formed at 30a. Although
it is preferred that the barrier strip 320 minimally
enter the side seal 30a area, it is to be understood that
the barrier strip may end before, at, or beyond the side
seal 30a at area 26a. An opening 123 is die punched in
the package 100' to provide a point where the package
100' may be easily hung for display purposes. As seen in
Figure 55, the package 100' is then cut along seam 101
from the bag making portion of the form fill and seal
machine and transferred to the fill and seal stations
where the side fill opening 300 is opened and the package
100' is filled through side fill opening 300. The
opening 300 is then hermetically sealed at seal 340. The
seal 340 is formed without use of a blade between.the
skirts 16, due to the presence of strip 320 between the
skirts 16 which prevents the inside surfaces 17 of skirts
16 from sealing together while the opening 300 is sealed.
It is to be understood that the gusseted, side fill
bags 100 and 100' having a backing or barrier strip 320
may alternatively include any of the features disclosed
with reference to the embodiments shown in Figures 1 -42.
Furthermore, although not shown in the Figures, it is
within the scope of the present invention to provide a
brush applied, anti-seal agent to the inside.surface'17
of zipper skirts 16. A brush applied, anti-seal agent.
such as nitrocellulose obtained from Amantceh may thereby
take the place of the. barrier or backing strip 320 and
provide a non-bonding function to the inside surface 17
of the zipper skirts 16 during seal of the fill opening
300.
The foregoing is considered as illustrative only of
the principles of the invention. Furthermore, since
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CA 02640953 2008-09-19
f i
numerous modification`s 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.