U.S. patent application number 12/609497 was filed with the patent office on 2011-05-05 for vented package.
This patent application is currently assigned to Sonoco Development, Inc.. Invention is credited to Brent Bosman.
Application Number | 20110103718 12/609497 |
Document ID | / |
Family ID | 43923129 |
Filed Date | 2011-05-05 |
United States Patent
Application |
20110103718 |
Kind Code |
A1 |
Bosman; Brent |
May 5, 2011 |
VENTED PACKAGE
Abstract
A package is provided having at least one panel formed from a
laminate having an inner sealing layer, an outer web layer and an
adhesive layer provided between the inner and outer layers. The
outer web layer includes a removable tab portion defined by a first
line of weakness in the layer. The inner sealing layer contains at
least one removable plug portion defined by a second line of
weakness. The first line of weakness is in registration with and
surrounds the second line of weakness. The adhesive layer includes
a permanent adhesive provided directly between at the tab and the
plug portion and a non-permanent adhesive within the remainder of
the area defined by the first line of weakness. Removal of the tab
from the outer web causes separation of the plug from the inner
layer, opening a vent within the package.
Inventors: |
Bosman; Brent; (Florence,
SC) |
Assignee: |
Sonoco Development, Inc.
Hartsville
SC
|
Family ID: |
43923129 |
Appl. No.: |
12/609497 |
Filed: |
October 30, 2009 |
Current U.S.
Class: |
383/66 ;
383/103 |
Current CPC
Class: |
B65D 2205/025 20130101;
B65D 75/008 20130101 |
Class at
Publication: |
383/66 ;
383/103 |
International
Class: |
B65D 33/01 20060101
B65D033/01; B65D 33/16 20060101 B65D033/16 |
Claims
1. A flexible package comprising: a first panel having an upper and
lower portion; a second panel having an upper and lower portion,
the first panel connected to the second panel along side edges of
the upper and lower portions; and a base panel connected to the
lower portions of the first and second panels and forming a bottom
gusset, the first, second and base panels defining an interior
package volume, at least one of the panels constructed from a
laminate material having an inner sealing layer, an outer web, and
an adhesive layer, the adhesive layer provided between the sealing
and outer web layers for joining the layers to one another, the
outer web having an integral tab portion defined by a first line of
weakness, the inner sealing layer having at least one integrally
formed plug portion defined by a second line of weakness, the plug
portion in registration with the area of the tab portion defined by
the first line of weakness, such that the tab portion covers and
surrounds the plug portion, and the adhesive layer having a
patterned permanent adhesive between the tab portion and the plug
portion and a patterned non-permanent adhesive in the registration
area outwardly of the second line of weakness and inwardly of the
first line of weakness.
2. The flexible package according to claim 1, further comprising a
plurality of plug portions defined by a plurality of second lines
of weakness within the sealing layer, the plurality of plug
portions in registration with and covered by the tab portion in the
outer web layer.
3. The flexible package according to claim 1, further comprising a
vacancy in the pattern applied adhesive layer located between the
tab of the outer web layer and the inner sealing layer, the vacancy
positioned adjacent an end portion of the tab as defined by the
first line of weakness, thereby forming a detached gripping portion
on the tab.
4. The flexible package according to claim 1, wherein the second
line of weakness defines a generally round vent opening, upon
removal of the tab along with the adhered plug portion.
5. The flexible package according to claim 1, wherein the first
line of weakness defines a generally elongated tab within the outer
web layer.
6. The flexible package according to claim 1, wherein the first
line of weakness comprises a perforation pattern within the outer
web layer.
7. The flexible package according to claim 1, wherein at least one
of the first or second lines of weakness is a die cut.
8. The flexible package according to claim 1, wherein at least one
of the first or second lines of weakness is a laser scoring.
9. The flexible package according to claim 1, wherein the tab
portion is located within the upper portion of the first panel.
10. The flexible package according to claim 1, wherein the pattern
of non-permanent adhesive is a pressure sensitive adhesive.
11. The flexible package according to claim 1, wherein the outer
web layer is polyester.
12. The flexible package according to claim 11, wherein the inner
sealing layer a heat-sealable material.
13. The flexible package according to claim 12, wherein the inner
sealing layer comprises a barrier against passage of at least one
of moisture and oxygen.
14. A package comprising: a flexible laminate forming an outer
surface of at least a portion of the package, the flexible laminate
having a continuous outer web layer an inner sealing layer
conforming to the outer web layer, an adhesive layer adhering the
outer web to the inner sealing layer, and a removable vent feature
formed in the laminate layers, the removable vent comprising an
outer tab portion defined by a first line of weakness in the outer
web layer, the tab portion of the outer web being releaseably
adhered by the adhesive layer to the underlying area of the inner
sealing layer; and at least one removable plug portion formed by a
second line of weakness in the inner sealing layer, the plug
portion fixedly adhered to tab portion, removal of the outer tab
portion along with the adhered plug portion creating a vent opening
in the package.
15. A package as in claim 14 wherein the region of the adhesive
layer located in the area between the first and second lines of
weakness comprises a pressure sensitive adhesive.
16. The package as in claim 14 wherein the first line of weakness
is a die cut line.
17. The package as in claim 14 wherein the first line of weakness
is a laser scoring.
18. The package as in claim 14 wherein the outer tab portion has an
elongated shape.
19. The package as in claim 14, further comprising multiple
removable plug portions, spaced from one another within the inner
sealing layer and each fixedly adhered to the tab portion of the
outer web layer.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to a flexible packaging
formed from a material laminate. More specifically, the present
disclosure relates to providing a sealed package with a removable
vent feature.
BACKGROUND
[0002] Flexible packaging, such as plastic bags or pouches, for
containment and storage of food products is known. In some
instances, it is desirable to store and cook food products in the
same packaging. One efficient way of cooking food within a flexible
package is by a microwave oven. However, sealed containers
typically experience increases in internal pressure during heating
of many food products. The increase in pressure within the package
results from the conversion of liquids to a gaseous state when
heated. Without means for allowing the escape of increased
pressure, the package may be subject to failure; causing a need for
clean-up or potentially harmful effects on the oven or its
environment. As a result, various types of flexible packaging for
food products include an opening or similar feature for the venting
of gases during heating.
[0003] One form of known vent is the use of a removable tape to
cover vent holes formed in the body of the package. The tape forms
an additional layer on the outside surface of the package material.
This requires an extra manufacturing step and affects the
appearance of the outer surface of the package.
[0004] U.S. Pat. No. 4,904,489 describes a system for convective
heating of food within a flexible package. In use, heated air is
forced through an inlet port and circulates around a separate pouch
contained within the bag. The forced air escapes the bag through
separate vent holes. During shipping, the vent holes are covered by
a removable tape.
[0005] U.S. Pat. No. 6,120,817 shows a flexible package having
ports that are separated from the contents of the package during
shipment. A zipper mechanism is heat sealed to the internal
surfaces of a package to provide the desired separation.
[0006] U.S. Pat. No. 6,637,939 shows a resealable package having a
zipper provided at the package opening. A sliding closing device is
provided on the zipper that includes a valve for controlled venting
of the bag during microwave cooking or the like.
SUMMARY
[0007] A package is provided having first and second panels that
are formed to define an interior volume for retaining a product,
such as food. At least one of the panels is constructed from a
laminate material having an inner sealing layer and an overlying
outer web layer. An adhesive layer is provided between the inner
and outer layers. The outer web layer contains an integrally formed
removable tab portion defined by a first line of weakness in the
wall of the web. The inner sealing layer contains at least one
integrally formed removable plug portion defined by a second line
of weakness in the wall of the layer. The first and second lines of
weakness are preferably in registration with one another, such that
the first line of weakness surrounds the area defined by second
line of weakness. In the registration area, the adhesive layer
comprises a permanent adhesive positioned between the portion of
the tab overlapping the plug and a removable or non-permanent
adhesive within the remainder of the registration area. The
removable plug portion in the inner sealing layer is permanently
adhered to the removable tab portion of the outer web.
[0008] During removal of the tab from the outer web, the tab
separates from the sealing layer due to the non-permanent adhesive.
In addition, the plug portion is adhered to the inner surface of
the tab, such that the removable of the tab also separates the plug
from the inner sealing layer, and opens a vent through the wall of
the package. The vent opening is defined by the position of the
outer web and inner sealing layer that are removed from the package
by the removal of the tab. Prior to removal, the two-ply laminate
seals the foodstuff or the like within the inner volume of the
package.
[0009] A base panel may also be provided, connected to a portion of
the first and second panels. The base panel may serve as a bottom
gusset to facilitate standing of the package.
[0010] Further features and advantages of the present invention
will become apparent by a review of the description below and a
review of the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For the purpose of illustrating the invention, the drawings
show forms that are presently preferred. It should be understood
that the invention is not limited to the precise arrangement and
instrumentality shown in the drawings.
[0012] FIG. 1 is a perspective view of a first exemplary embodiment
of a package having a vent.
[0013] FIG. 2 is a cross-sectional view of the package of FIG. 1,
taken along the line 2-2.
[0014] FIG. 3 is a cross-sectional view of the package of FIG. 1,
taken along the line 2-2, with a tab portion removed from the wall
of the package a vent being defined.
[0015] FIG. 4 is a cross-sectional view of the package of FIG. 1,
taken along the line 4-4.
[0016] FIG. 5 is a cross-sectional view of the package of FIG. 1,
taken along the line 5-5.
[0017] FIG. 6 is a cross-sectional view of the package of FIG. 1,
taken along the line 5-5 with a vent portion defined within the
package.
DETAILED DESCRIPTION
[0018] Referring to the figures, like numerals are used to indicate
like elements throughout. FIGS. 1-6 show an embodiment of a
flexible package generally identified by reference numeral 10. The
package 10 is shown as having a generally rectangular construction,
but may have any desired shape. As illustrated, the package 10
includes a first panel 12 having a removable tab 14, which covers
formed vents 16.
[0019] Referring to FIG. 1, the package 10 is shown in the form of
a stand up pouch having a first panel 12, an opposing second panel
18 and a bottom gusset panel 20. The first panel 12 is secured to
the second panel 18 by a heat seal 22 extending along their top
edges and along the upper side portions of the package 10. The
gusset panel 20 is also preferably heat-sealed to the first panel
12 and second panel 18 adjacent their lower portions and along
their bottom edges, providing a base for the package 10.
[0020] As shown in FIGS. 2 and 3, the first and second panels 12,
18 are constructed of a multi-layer laminate material 30, having at
least a first layer 24 and a second layer 26. The first and second
layers are preferably joined together by an adhesive layer 28. The
first and second layers 24, 26 respectively define inner and outer
surfaces for at least a portion of the package. The first layer 24
may be an outer web, including one or more components. It is
preferable that the first layer 24 be formed by a polyester
material that is suitable for receiving printing, such as for
labeling purposes. The second layer 26 preferably serves as the
inner sealing layer for the laminate material 30 and, again, may be
constructed of one or more components. It is preferable that the
second layer 26 be constructed of an oriented polypropylene that is
capable of being sealed to itself, or another compatible materials
or layers, upon the application of heat and pressure.
[0021] A first line of weakness 34 is located in the outer web of
the first layer 24 and defines the removable tab 14. Preferably,
the removable tab 14 is located in an upper portion of the first
panel 12. As seen best in FIGS. 2 and 3, the first line of weakness
34 preferably extends through at least a portion of the web
material of the first layer 24 and does not extend into the second
layer 26, thereby leaving the second layer 26 in tact and
maintaining the seal and integrity of the package. Prior to adding
the line of weakness 34, the material of the tab 14 is integrally
formed with the remainder of the outer web 24.
[0022] Second lines of weakness 36 are provided within the second
layer 26 and define the outline of vent holes 16. The material
portions of the second layer 26 that are defined inside the second
lines of weakness 36 are referred to as plug portions 40. There may
be any number of vents 16, which may be formed by defined plugs 40
of any suitable shape. It is preferable that the plug portions 40
are covered by the tab portion 14, with the second lines of
weakness 36 positioned within the defined area of the first line of
weakness 34. Thus, the plugs 40 and their corresponding vents 16
are in registration with the tab 14 within the formed package.
[0023] The first and second lines of weakness 34, 36 may be foil
led by laser scoring, die cut or other known method and may be a
continuous score line or a perforation pattern. The goal of the
pattern is to maintain the integrity of the layers and the
integrally defined tab portion 14 and plugs 40, while also
providing for clean separation of the tab and plugs during
removal.
[0024] The adhesive layer 28 joins the first and second layers 24,
26 and is preferably pattern applied during the formation of the
laminate. In the preferred embodiment, the adhesive layer 28
includes multiple types or strengths of adhesive. A layer of
non-permanent or releasable adhesive 32 is providing in the area of
the tab 16, defined by the first line of weakness 34. Thus, the tab
14 may be removed from the package wall using a moderate peeling
force. The non-permanent adhesive 32 may be a pressure-sensitive
adhesive or any other relatively weak or releasable adhesive that
will provide sufficient integrity to the package layers while
permitting separation of the outer web 24 upon the application of
the peeling or separation force.
[0025] A permanent adhesive 38 is provided in certain areas where a
relatively stronger bond is desired, as compared to that created by
the non-permanent adhesive. Thus, the permanent adhesive 38 is
contemplated to secure the adjacent materials together, requiring a
destructive force for the separation of the materials. As shown in
FIGS. 2 and 3, the permanent adhesive 38 is provided between the
plug portions 40 and the inside surface of the tab portion 14.
Thus, the plug portions 40 are permanently adhered to the inside of
the tab 14. The permanent adhesive 38 may also be used to secure
the remainder of the web layer 24 to the sealing layer 26, outside
of the first line of weakness 34.
[0026] Although not specifically identified in the drawings, a
vacancy in the adhesive pattern may be located near a first end 42
of the tab 14 to facilitate lifting and separation of the tab 14
from the remainder of the outer web 24. The lack of an adhesive may
make it easier to start peeling the tab 14 away from the inner
layer 26. The adhesive vacancy may be formed by a gap in the
pattern adhesive or by blocking the adhesive provided in the area
of the end 42 of the tab 14.
[0027] FIGS. 4-6 show side cross-sectional views of the area of the
package 10 around the removable tab 14 and the defined vents 16.
FIG. 4 shows a cross-sectional view of the package 10 taken in an
area of the tab 14 defined in the outer web layer 24, where the tab
14 does not cover a plug portion 40 in the adjacent portion of the
second layer 26. The tab portion 14, defined by the first line of
weakness 34, is shown connected to the outer web 24 and adhered to
the underlying sealing layer 26 by a non-permanent adhesive 32.
FIG. 5 shows a cross-sectional view taken across the removable tab
14 in the area of one of the plug portions 40, which is defined by
the second lines of weakness 36 in the sealing layer. The first end
42 of the removable tab 14 is shown as partially peeled away from
the first panel 12. The portion of the tab 14 that is overlying the
plug portion 40 is joined to the plug by a permanent adhesive 38.
In FIG. 5, the vent hole 16 is closed by the plug, formed from the
material of the sealing layer 26. FIG. 6 shows the tab 14 removed
from first panel 12. A vent hole 16 is defined by the removal of
the plug 40, which remains adhered to the tab 14 and is removed
along with the tab due to the permanent adhesive 38. The vent 16
extends through the inner layer 26 and is open to the atmosphere
outside the package, by the removal of tab portion 14 of the outer
web layer 24. In FIG. 6, the gas within the package is permitted to
escape "B" through the panel 12.
[0028] In use, the package 10 may be stored in any position (i.e.
upright, on its side or housing). The package 10 may be stored at
room temperature, refrigerated or frozen, depending on the contents
and desires of the user. Prior to heating the contents of the
package 10, such as by using a microwave oven (not shown), the tab
14 and plug portions 40 may be removed by peeling the tab 14,
starting at "A" in FIGS. 3 and 5. As the tab 14 is removed from the
outer web 24, the plug portions 40 are also removed from the inner
layer 26 as shown by FIG. 3. During heating, the steam and gas
pressure that builds within the package 10 may escape through the
open vents 16, as shown by "B" in FIG. 6.
[0029] The non-permanent adhesive 32 may be one of any known
compositions. By way of example pressure-sensitive adhesives form
viscoelastic bonds that are aggressively and permanently tacky,
adhere without the need of more than a finger or hand pressure, and
require no activation by water, solvent or heat. Pressure-sensitive
adhesives are often used and may be based on non-crosslinked rubber
adhesives in a latex emulsion or solvent-borne form, or can
comprise acrylic and methacrylate adhesives, styrene copolymers
(SIS/SBS) and silicones. Acrylic adhesives are known for
environmental resistance and fast-setting time when compared with
other resin systems. Acrylic pressure-sensitive adhesives often use
an acrylate system. Natural rubber, synthetic rubber or elastomer
sealants and adhesives can be based on a variety of systems, such
as silicone, polyurethane, chloroprene, butyl, polybutadiene,
isoprene, or neoprene.
[0030] As one primary use of the package 10 is for containing food,
it is preferable that the non-permanent adhesive 32 be a food-grade
composition. By way of example, various pressure-sensitive
adhesives are approved by the US Food and Drug Administration, as
regulated by 21 CFR Part 175.300. A preferred food-grade
pressure-sensitive adhesive for use in the present invention is
Jonbond 743, available from Bostik Findley. Additives (e.g.,
particulates or the like) can be included in the non-permanent
adhesive 32 to reduce the tenacity of the bond to either of the
laminate layers, if desired, so that the non-permanent adhesive 32
readily detaches from one of the laminate layers, upon removal of
the tab 14.
[0031] The permanent adhesive may be of any known composition. A
suitable example includes two-component polyurethane adhesive
systems, such as Tycel 7900/7283 available from Henkel.
[0032] Polyester is mentioned above as the preferred material of
the two laminate layers. Various materials may also be used within
the laminate layers, including polyesters, polyolefins (including
homopolymers and copolymers), polyamides, paper and the like.
[0033] In addition, the inner layer may include a barrier layer
(not shown) including barrier polymer films, such as ethylene vinyl
alcohol copolymer (EVOH), polyamide and the like.
[0034] Preferably, the inner and outer layers have the same surface
area and are continuous within the formation of a package panel. An
ink layer (not shown) may be provided between the laminate layers.
For example, page indicia and graphics may be reverse printed on
the inside surface of the outer web layer. The ink layer would then
be brought into contact with the adhesive layer 28 when forming the
package laminate. A number of package forms are contemplated. The
stand-up pouch in FIG. 1 is one potential embodiment. A bottom
gusset panel 20 is not required to form a package having the
contemplated invention. Side gussets (not shown) may be provided
within the package, if desired. As such, the flexible laminate of
the present invention may be formed as part of other packaging
arrangements, including vertical form-fill-seal packages, flow
wraps, pillow packs, etc.
[0035] Although the invention has been described and illustrated
with respect to the exemplary embodiments thereof, it should be
understood by those skilled in the art that the foregoing and
various other changes, omissions and additions may be made therein
and thereto, without parting from the spirit and scope of the
present invention. Accordingly, reference should be made to the
appended claims, rather than to the foregoing specification, as
indicating the scope of the invention.
* * * * *