U.S. patent application number 10/795149 was filed with the patent office on 2005-02-17 for liquid-trapping bag for use in vacuum packaging.
This patent application is currently assigned to Tilia International, Inc.. Invention is credited to Albritton, Charles Wade, Brakes, David, Wu, Hongyu.
Application Number | 20050037164 10/795149 |
Document ID | / |
Family ID | 34140022 |
Filed Date | 2005-02-17 |
United States Patent
Application |
20050037164 |
Kind Code |
A1 |
Wu, Hongyu ; et al. |
February 17, 2005 |
Liquid-trapping bag for use in vacuum packaging
Abstract
A bag for use in vacuum packaging comprises a first panel and a
second panel overlapping each other. A plurality of channels having
a plurality of baffles is formed on one or more of the panels for
evacuating air and/or other gases from inside the bag using a
suction source, while preventing liquids from being drawn into the
suction source. This description is not intended to be a complete
description of, or limit the scope of, the invention. Other
features, aspects, and objects of the invention can be obtained
from a review of the specification, the figures, and the
claims.
Inventors: |
Wu, Hongyu; (San Jose,
CA) ; Albritton, Charles Wade; (Hercules, CA)
; Brakes, David; (Kowloon, CN) |
Correspondence
Address: |
FLIESLER MEYER, LLP
FOUR EMBARCADERO CENTER
SUITE 400
SAN FRANCISCO
CA
94111
US
|
Assignee: |
Tilia International, Inc.
San Francisco
CA
|
Family ID: |
34140022 |
Appl. No.: |
10/795149 |
Filed: |
March 4, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60452168 |
Mar 5, 2003 |
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60452172 |
Mar 5, 2003 |
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60452171 |
Mar 5, 2003 |
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60451954 |
Mar 5, 2003 |
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60451948 |
Mar 5, 2003 |
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60452142 |
Mar 5, 2003 |
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60452021 |
Mar 5, 2003 |
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60451955 |
Mar 5, 2003 |
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60451956 |
Mar 5, 2003 |
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60452157 |
Mar 5, 2003 |
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60452139 |
Mar 5, 2003 |
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Current U.S.
Class: |
428/34.2 |
Current CPC
Class: |
B31B 2241/00 20130101;
B65D 31/02 20130101; B65D 81/2023 20130101; B65B 61/025 20130101;
B32B 38/004 20130101; B65B 2009/047 20130101; B32B 2323/04
20130101; B32B 27/08 20130101; B32B 2439/70 20130101; B65D 33/004
20130101; B65B 9/042 20130101; B32B 2307/7242 20130101; B65D
81/2038 20130101; B32B 3/26 20130101; B32B 3/30 20130101; B32B
2439/46 20130101; B32B 3/04 20130101; B32B 2307/31 20130101; Y10T
428/1303 20150115; B32B 37/0076 20130101; B65D 33/00 20130101 |
Class at
Publication: |
428/034.2 |
International
Class: |
B65D 001/00 |
Claims
1. A bag adapted to receive an article, comprising: a first panel
including a plurality of protuberances; a second panel; and the
first panel and the second panel secured together to form the
bag.
2. A bag adapted to receive an article, comprising: a first panel
having: a first outer layer; and a first inner layer connected with
the first outer layer, the first inner layer including a plurality
of protuberances; and a second panel connected with the first panel
such that the first panel and the second panel form an envelope
having an inlet, the second panel having: a second outer layer; and
a second inner layer connected with the second outer layer; wherein
when the first inner layer contacts the second inner layer the
plurality of protuberances obstruct liquid flow through the
inlet.
3. The bag of claim 2, wherein the first outer layer and the second
outer layer comprise a gas-impermeable material.
4. The bag of claim 3, wherein the gas-impermeable material is one
of polyester, polyamide, ethylene vinyl alcohol, and nylon.
5. The bag of claim 2, wherein the first inner layer and the second
inner layer comprise a thermoplastic resin.
6. The bag of claim 5, wherein the thermoplastic resin is
polyethylene.
7. The bag of claim 2, wherein the plurality of protuberances
define a plurality of channels.
8. The bag of claim 7, wherein the plurality of channels includes a
plurality of baffles.
9. The bag of claim 8, wherein the plurality of baffles are
arranged in a herringbone pattern.
10. The bag of claim 8, wherein the plurality of baffles form a
plurality of pockets for trapping liquid particles.
11. The bag of claim 2, wherein the plurality of protuberances
define a plurality of baffles.
12. The bag of claim 11, wherein the plurality of baffles form a
plurality of pockets for trapping liquid particles.
13. The bag of claim 8, wherein the plurality of baffles comprise a
U-shape.
14. The bag of claim 13, wherein the plurality of baffles include a
slit in a trough of the U-shape, the slit being sized such that gas
can pass through the slit.
15. A bag adapted to receive an article, comprising: a first panel
including: a first gas-impermeable layer; and a first inner layer
laminated to the first gas-impermeable layer, the first inner layer
having a textured exposed surface; wherein the textured exposed
surface obstructs liquid flow when gas is evacuated through the
heat-sealable opening; and a second panel including: a second
gas-impermeable layer; and a second inner layer laminated to the
second gas-impermeable layer; wherein the first panel is connected
with the second panel to form an envelope such that the first inner
layer opposes the second inner layer, the envelope including a
heat-sealable opening for evacuating gas.
16. A heat-sealable bag adapted to receive an article, comprising:
a first panel including: a first gas-impermeable layer; at least
one first intermediate layer connected with the first
gas-impermeable layer; and a first inner layer laminated to the at
least one first intermediate layer, the first inner layer having a
textured exposed surface; wherein the textured exposed surface
obstructs liquid flow when gas is evacuated through the
heat-sealable opening; and a second panel including: a second
gas-impermeable layer; at least one second intermediate layer
connected with the second gas-impermeable layer; and a second inner
layer laminated to the at least one second intermediate layer;
wherein the first panel is connected with the second panel to form
an envelope such that the first inner layer opposes the second
inner layer, the envelope including a heat-sealable opening for
evacuating gas.
17. The bag of claim 16, wherein the first gas-impermeable layer
and the second gas-impermeable layer comprise one of polyester,
polyamide, ethylene vinyl alcohol, and nylon.
18. The bag of claim 16, wherein the first inner layer and the
second inner layer comprise a thermoplastic resin.
19. The bag of claim 18, wherein the thermoplastic resin is
polyethylene.
20. The bag of claim 16, wherein the textured exposed surface
comprises a plurality of channels.
21. The bag of claim 20, wherein the textured exposed surface
further comprises a plurality of baffles.
22. The bag of claim 21, wherein the plurality of baffles are
arranged in a herringbone pattern.
23. The bag of claim 21, wherein the plurality of baffles form a
plurality of pockets for trapping liquid particles.
24. The bag of claim 16, wherein the textured exposed surface
comprises a plurality of baffles.
25. The bag of claim 24, wherein the plurality of baffles form a
plurality of pockets for trapping liquid particles.
26. The bag of claim 24, wherein the plurality of baffles comprise
a U-shape.
27. The bag of claim 26, wherein the plurality of baffles includes
a slit in a trough of the U-shape, the slit being sized such that
air can pass through the slit.
28. A bag adapted to receive an article, comprising: a first panel
defining a plurality of receptacles adapted to trap a liquid and a
plurality of channels that pass by said receptacles, which channels
are adapted to allow the passage of a gas; a second panel; and the
first panel and the second panel secured together to form the
bag.
29. A bag adapted to receive an article, comprising: a first panel
defining a plurality of receptacles adapted to trap a liquid, which
receptacles are formed with a first wall that runs about along a
length of the bag and a plurality of second walls that run in a
direction that is across the length of the bag; a second panel; and
the first panel and the second panel secured together to form the
bag.
30. A system for forming a bag including a three-dimensional
structure formed on at least one panel, comprising: a cooling roll
having a plurality of cavities for forming one or more structures;
wherein the one or more structures include a plurality of
receptacles adapted to trap a liquid; a laminating roll; a backing
material; and a flowable material that can be flowed into the one
or more cavities to form the one or more structures, the flowable
material adhering to the backing material.
Description
PRIORITY CLAIM
[0001] This application claims priority to the following U.S.
Provisional Patent Application:
[0002] U.S. Provisional Patent Application No. 60/452,168, entitled
"LIQUID-TRAPPING BAG FOR USE IN VACUUM PACKAGING," by Henry Wu, et
al., filed Mar. 5, 2003 (Attorney Docket No. TILA-01177US0).
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0003] This U.S. patent application incorporates by reference all
of the following co-pending applications:
[0004] U.S. Provisional Patent Application No. 60/452,138, entitled
"METHOD FOR MANUFACTURING LIQUID-TRAPPING BAG FOR USE IN VACUUM
PACKAGING," by Henry Wu, et al., filed Mar. 5, 2003 (Attorney
Docket No. TILA-01177US1);
[0005] U.S. Provisional Patent Application No. 60/452,172, entitled
"SEALABLE BAG HAVING AN INTEGRATED TRAY FOR USE IN VACUUM
PACKAGING," by Henry Wu, et al., filed Mar. 5, 2003 (Attorney
Docket No. TILA-01178US0);
[0006] U.S. Provisional Patent Application No. 60/452,171, entitled
"METHOD FOR MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED TRAY
FOR USE IN VACUUM PACKAGING," by Henry Wu, et al., filed Mar. 5,
2003 (Attorney Docket No. TILA-01178US1);
[0007] U.S. Provisional Patent Application No. 60/451,954, entitled
"SEALABLE BAG HAVING AN INDICIA FOR USE IN VACUUM PACKAGING," by
Henry Wu, et al., filed Mar. 5, 2003 (Attorney Docket No.
TILA-01179US0);
[0008] U.S. Provisional Patent Application No. 60/451,948, entitled
"METHOD FOR MANUFACTURING A SEALABLE BAG HAVING AN INDICIA FOR USE
IN VACUUM PACKAGING," by Henry Wu, et al., filed Mar. 5, 2003
(Attorney Docket No. TILA-01179US1);
[0009] U.S. Provisional Patent Application No. 60/452,142, entitled
"SEALABLE BAG HAVING AN INTEGRATED ZIPPER FOR USE IN VACUUM
PACKAGING," by Henry Wu, et al., filed Mar. 5, 2003 (Attorney
Docket No. TILA-01180US0);
[0010] U.S. Provisional Patent Application No. 60/452,021, entitled
"METHOD FOR MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED
ZIPPER FOR USE IN VACUUM PACKAGING," by Henry Wu, et al., filed
Mar. 5, 2003 (Attorney Docket No. TILA-01180US1);
[0011] U.S. Provisional Patent Application No. 60/451,955, entitled
"SEALABLE BAG HAVING AN INTEGRATED VALVE STRUCTURE FOR USE IN
VACUUM PACKAGING," by Henry Wu, et al., filed Mar. 5, 2003
(Attorney Docket No. TILA-01181US0);
[0012] U.S. Provisional Patent Application No. 60/451,956, entitled
"METHOD FOR MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED VALVE
STRUCTURE FOR USE IN VACUUM PACKAGING," by Henry Wu, et al., filed
Mar. 5, 2003 (Attorney Docket No. TILA-01181US1);
[0013] U.S. Provisional Patent Application No. 60/452,157, entitled
"SEALABLE BAG HAVING AN INTEGRATED TIMER/SENSOR FOR USE IN VACUUM
PACKAGING," by Henry Wu, et al., filed Mar. 5, 2003 (Attorney
Docket No. TILA-01182US0);
[0014] U.S. Provisional Patent Application No. 60/452,139, entitled
"METHOD FOR MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED
TIMER/SENSOR FOR USE IN VACUUM PACKAGING," by Henry Wu, et al.,
filed Mar. 5, 2003 (Attorney Docket No. TILA-01182US1);
[0015] U.S. patent application Ser. No. 10/169,485, entitled
"METHOD FOR PREPARING AIR CHANNEL EQUIPPED FILM FOR USE IN VACUUM
PACKAGE," filed Jun. 26, 2002;
[0016] U.S. patent application Ser. No. ______, entitled "METHOD
FOR MANUFACTURING LIQUID-TRAPPING BAG FOR USE IN VACUUM PACKAGING,"
Attorney Docket No. TILA-01177US3, filed concurrently;
[0017] U.S. patent application Ser. No. ______, entitled "SEALABLE
BAG HAVING AN INTEGRATED TRAY FOR USE IN VACUUM PACKAGING,"
Attorney Docket No. TILA-01178US2, filed concurrently;
[0018] U.S. patent application Ser. No. ______, entitled "METHOD
FOR MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED TRAY FOR USE
IN VACUUM PACKAGING," Attorney Docket No. TILA-01178US3, filed
concurrently;
[0019] U.S. patent application Ser. No. ______, entitled "SEALABLE
BAG HAVING AN INDICIA FOR USE IN VACUUM PACKAGING," Attorney Docket
No. TILA-01179US2, filed concurrently;
[0020] U.S. patent application Ser. No. ______, entitled "METHOD
FOR MANUFACTURING A SEALABLE BAG HAVING AN INDICIA FOR USE IN
VACUUM PACKAGING," Attorney Docket No. TILA-01179US3, filed
concurrently;
[0021] U.S. patent application Ser. No. ______, entitled "SEALABLE
BAG HAVING AN INTEGRATED ZIPPER FOR USE IN VACUUM PACKAGING,"
Attorney Docket No. TILA-01180US2, filed concurrently;
[0022] U.S. patent application Ser. No. ______, entitled "METHOD
FOR MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED ZIPPER FOR
USE IN VACUUM PACKAGING," Attorney Docket No. TILA-01180US3, filed
concurrently;
[0023] U.S. patent application Ser. No. ______, entitled "SEALABLE
BAG HAVING AN INTEGRATED VALVE STRUCTURE FOR USE IN VACUUM
PACKAGING," Attorney Docket No. TILA-01181US2, filed
concurrently;
[0024] U.S. patent application Ser. No. ______, entitled "METHOD
FOR MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED VALVE
STRUCTURE FOR USE IN VACUUM PACKAGING," Attorney Docket No.
TILA-01181US3, filed concurrently;
[0025] U.S. patent application Ser. No. ______, entitled "SEALABLE
BAG HAVING AN INTEGRATED TIMER/SENSOR FOR USE IN VACUUM PACKAGING,"
Attorney Docket No. TILA-01182US2, filed concurrently; and
[0026] U.S. patent application Ser. No. ______, entitled"METHOD FOR
MANUFACTURING A SEALABLE BAG HAVING AN INTEGRATED TIMER/SENSOR FOR
USE IN VACUUM PACKAGING," Attorney Docket No. TILA-01182US3, filed
concurrently.
FIELD OF THE INVENTION
[0027] The present invention relates to bags for use in vacuum
packaging and methods and devices for manufacturing bags for use in
vacuum packaging.
BACKGROUND
[0028] Methods and devices for preserving perishable foods such as
fish and meats, processed foods, prepared meals, and left-overs,
and non-perishable items are widely known, and widely varied. Foods
are perishable because organisms such as bacteria, fungus and mold
grow over time after a food container is opened and the food is
left exposed to the atmosphere. Most methods and devices preserve
food by protecting food from organism-filled air. A common method
and device includes placing food into a gas-impermeable plastic
bag, evacuating the air from the bag using suction from a vacuum
pump or other suction source, and tightly sealing the bag.
[0029] A bag for use in vacuum packaging can consist of a first
panel and second panel, each panel consisting of a single layer of
heat-sealable, plastic-based film (for example, polyethylene). The
panels are sealed together along a substantial portion of the
periphery of the panels by heat-sealing techniques so as to form an
envelope. Perishable products, such as spoilable food, or other
products are packed into the envelope via the unsealed portion
through which air is subsequently evacuated. After perishable
products are packed into the bag and air is evacuated from the
inside of the bag, the unsealed portion is heated and pressed such
that the panels adhere to each other, sealing the bag.
[0030] U.S. Pat. No. 2,778,173, incorporated herein by reference,
discloses a method for improving the evacuation of air from the bag
by forming channels in at least one of the panels with the aid of
embossing techniques. Air escapes from the bag along the channels
during evacuation. The embossing forms a pattern of protuberances
on at least one of the panels. The protuberances can be discrete
pyramids, hemispheres, etc., and are formed by pressing a panel
using heated female and male dies. The first panel is overlaid on
the second panel such that the protuberances from one panel face
the opposite panel. The contacting peripheral edges of the panels
are sealed to each other to form an envelope having an inlet at an
unsealed portion of the periphery. The perishable or other products
are packed into the envelope through the inlet, and the inlet is
sealed. Thereafter, an opening is pierced in a part of the panel
material that communicates with the charnels, air is removed from
the interior of the envelope through the channels and opening, and
the opening is sealed. This type of bag requires two additional
sealing steps after the perishable or other product is packed into
the envelope. One further problem is that embossing creates
impressions on the plastic such that indentations are formed on the
opposite side of the panel
[0031] To avoid additional sealing steps, a vacuum bag is formed
having a first panel and a second panel consisting of laminated
films. Each panel comprises a heat-sealable inner layer, a
gas-impermeable outer layer, and optionally, one or more
intermediate layers. Such a bag is described in U.S. Pat. No. Re.
34,929, incorporated herein by reference. At least one film from at
least one panel is embossed using an embossing mold to form
protuberances and channels defined by the space between
protuberances, so that air is readily evacuated from the vacuum
bag.
[0032] U.S. Pat. No. 5,554,423, incorporated herein by reference,
discloses still another bag usable in vacuum packaging. The bag
consists of a first and second panel, each panel consisting of a
gas-impermeable outer layer and a heat-sealable inner layer. A
plurality of heat-sealable strand elements are heat bonded at
regular intervals to the inner layer of either the first panel or
the second panel. The spaces between strand elements act as
channels for the evacuation of air. The strand elements are
extruded from an extrusion head and heat bonded to the
heat-sealable layer by use of pressure rolls. Separate equipment is
required for producing strand elements, and a procedure of heat
bonding a plurality of strand elements at regular intervals to the
heat-sealable inner layer is complicated. Also, various shapes of
pattern are hard to form using this process.
BRIEF DESCRIPTION OF THE FIGURES
[0033] Further details of embodiments of the present invention are
explained with the help of the attached drawings in which:
[0034] FIG. 1A is a perspective view of a method for manufacturing
a vacuum bag in accordance with one embodiment of the present
invention;
[0035] FIG. 1B is a side view of the method shown in FIG. 1A
illustrating the embossing method used in an embodiment of the
present invention;
[0036] FIG. 1C is a close-up view of a portion of FIG. 1B;
[0037] FIG. 2A is a top view of a partial portion of a first panel
overlapping a partial portion of a second panel in accordance with
one embodiment of the present invention;
[0038] FIG. 2B is a cross-section view through line 2B-2B of FIG.
2A;
[0039] FIG. 3A-3E are plan views of exemplary patterns on a panel
in accordance with embodiments of the present invention,
manufactured by the process shown in FIG. 1; and
[0040] FIG. 4 is a perspective view of a vacuum bag in accordance
with one embodiment of the present invention.
DETAILED DESCRIPTION
[0041] The detailed embodiments of the present invention are
disclosed herein. It should be understood, however, that the
disclosed embodiments are merely exemplary of the invention, which
may be embodied in various forms. Therefore, the details disclosed
herein are not to be interpreted as limiting, but merely as the
basis for the claims and as a basis for teaching one skilled in the
art how to make and/or use the invention.
[0042] FIGS. 1A-1C illustrate one embodiment of a method for
manufacturing a vacuum bag in accordance with the present
invention. The vacuum bag comprises a first panel and a second
panel, wherein each panel comprises a gas-impermeable base layer
108 and a heat-sealable inner layer 106 with at least one panel
having liquid flow obstructing protuberances and/or channels. A
laminating roll 102 and a cooling roll 104 are arranged so that
melt-extruded resin can be introduced between the rolls and cooled
to form the heat-sealable inner layer 106 and to laminate the
formed inner layer 106 to the gas-impermeable base layer 108. As
illustrated in FIG. 1C, a gap between the laminating roll 102 and
the cooling roll 104 can be controlled according to specifications
(for example, thickness) of a panel for use in vacuum packaging.
The temperature of the cooling roll 104 is maintained in a range
such that the melt-extruded resin can be sufficiently cooled to
form a desired pattern. For example, a temperature range of about
-15.degree. C. to about -10.degree. C. can be sufficient to
properly form the desired pattern. The temperature range of the
cooling roll 104 can vary according to the composition of the
resin, the composition of the gas-impermeable base layer 108,
environmental conditions, etc. and can require calibration. Also,
the cooling roll 104 can be sized to have a larger diameter than
the laminating roll 102, thereby bringing the melt-extruded resin
into contact with more cooled surface area. For example, the
diameter of the cooling roll 104 can be about one-and-a-half to
about three times as large (or more) as that of the laminating roll
102.
[0043] The heat-sealable inner layer 106 typically comprises a
thermoplastic resin. For example, the resin can be comprised of
polyethylene (PE) suitable for preserving foods and harmless to a
human body. A vacuum bag can be manufactured by overlapping two
panels such that the heat-sealable inner layers 106 of the two
panels are brought into contact and heat is applied to a portion of
the periphery of the panels to form an envelope. The thermoplastic
resin can be chosen so that the two panels strongly bond to each
other when sufficient heat is applied.
[0044] The gas-impermeable base layer 108 is fed to the gap between
the cooling roll 104 and the laminating roll 102 by a feeding means
(not shown). The gas-impermeable base layer can be comprised of
polyester, polyamide, ethylene vinyl alcohol (EVOH), nylon, or
other material having similar properties, that is capable of being
heated and capable of being used in this manufacturing process. The
gas-impermeable base layer 108 can consist of one layer, or two or
more layers. When employing a multilayer-structured base layer, it
should be understood that a total thickness thereof is also
adjusted within the allowable range for the total gas-impermeable
base layer 108.
[0045] An extruder 110 is positioned in such a way that the
melt-extruded resin is layered on the gas-impermeable base layer
108 by feeding the melt-extruded resin to a nip between the cooling
roll 104 and the gas-impermeable base layer 108. The resin is fed
through a nozzle 112 of the extruder 110. The temperature of the
melt-extruded resin is dependent on the type of resin used, and can
typically range from about 200.degree. C. to about 250.degree. C.
The amount of resin extruded into the laminating unit 100 is
dependent on the desired thickness of the heat-sealable inner layer
106.
[0046] A pattern fabricated on the circumferential surface of the
cooling roll 104 in accordance with one embodiment of the present
invention can include cavities (and/or protuberances) defining a
plurality of discrete channels having a baffled structure. The
resin extruded from the nozzle 112 is pressed between the cooling
roll 104 and the gas-impermeable base layer 108 and flows into the
cavities of the cooling roll 104. The resin quickly cools and
solidifies in the desired pattern while adhering to the
gas-impermeable base layer 108, thereby forming the heat-sealable
inner layer 106 of the panel. The heat-sealable inner layer 106 can
be formed while the resin is sufficiently heated to allow the resin
to flow, thereby molding the resin, unlike other methods adopting a
post-embossing treatment where the heat-sealable inner layer is
drawn by a die or embossed between male and female components.
[0047] The thickness of each protuberance formed on the
heat-sealable inner layer 106 of a panel can be determined by the
depth of the cavities of the cooling roll 104, and the width of the
channel can be determined by the interval between the cavities.
Thus, the shape, width, and thickness of the channels for the
evacuation of air and/or other gases can be controlled by changing
the specifications for the cavities of the cooling roll 104. FIGS.
2A and 2B illustrate a cross-section (along line 2B-2B) of two
panels in accordance with one embodiment of the present invention
(the thickness of the panels are exaggerated relative to the width
of the channel walls and baffles). The heat-sealable inner layer
106 can range from preferably 0.5-6.0 mils in thickness at the
channels 224, and preferably 1.0-12.0 mils in thickness at the
protuberances 226,228, while the gas-impermeable base layer 108 can
range from about preferably 0.5-8.0 mils in thickness. The
dimensions of the inner layer and the base layer are set forth to
illustrate, but are not to be construed to limit the dimensions of
the inner layer and the base layer.
[0048] FIG. 3A is a plan view of a pattern 320 formed on a panel by
the cooling roll 104 for use in a vacuum bag, in which the
heat-sealable inner layer 106 is molded in such a way that
protuberances form the plurality of channels 224 having channels
walls 226 and baffles 228. The baffles 228 can be arranged in a
herringbone pattern at angles such that air and/or other gases 340
(shown schematically) can be drawn around the baffles 228 by
suction and evacuated from the vacuum bag, while heavier liquid
particles 342 can be trapped between the channel walls 226 and the
baffles 228. Angles formed by the intersection of baffles 228 and
channel walls 226, and gaps between adjacent baffles 228 can be
defined when producing the cooling roll 104 to suit the liquid
intended to be trapped. Different arrangements of the baffles 228
relative to the chamber walls 226, and relative to other baffles
228 can be multi-fold (shaped to define liquid-trapping vessels),
and can be optimized to improve evacuation of the air and/or other
gases 340, while effectively preventing liquids 342 from being
drawn out of the vacuum bag. For example, as shown in FIG. 3A the
baffles 228 can be arranged such that an approach angle for passing
through the channel opening between the baffles 228 is severe and
that vessels formed by the baffles 228 are relatively deep, thereby
retarding liquid flow by deflecting liquid 342 into the vessels and
trapping a significant amount of liquid 342.
[0049] As indicated above, one of ordinary skill in the art can
appreciate the multitude of different baffle arrangements for
retarding the evacuation of liquid 342 relative to the evacuation
of air and/or other gases 340. As shown in FIG. 3B, in other
embodiments a pattern 320 fabricated on the circumferential surface
of the cooling roll 104, and thereafter the panel, can mold
protuberances forming a plurality of channels 224 defined by
"V"-shaped baffles 228, eliminating the need for molding channel
walls. In still other embodiments, the channel walls 226 can extend
substantially the length of the panel with only a portion of the
length of the channels near an evacuation opening having baffles
228.
[0050] As shown in FIG. 3C, in other embodiments a pattern 320
fabricated on the circumferential surface of the cooling roll 104,
and thereafter the panel, can mold protuberances forming a
plurality of channels 224 having channels walls 226 and baffles
228, wherein each baffle 228 extends across a substantial portion
of the width of the channel 224, thereby defining a path between
the baffle 228 and the channel wall 226 for the air and/or other
gases 340 to be drawn. The baffles 228 can alternatively be
parabolic or rounded, as shown in FIG. 3D, to form pockets for
collecting liquid particles 342.
[0051] FIG. 3E illustrates still another embodiment of a pattern
320 fabricated on the circumferential surface of the cooling roll
104, and thereafter the panel, that can include
parabolically-shaped or "U"-shaped baffles 228 arranged like
fish-scales either along the length of the panel, or a portion of
the panel to capture liquid particles 342. The U-shaped baffles 228
can also include slits 330 in the troughs of the U-shaped baffles
228 small enough to improve the flow of air and/or other gases 340
while retarding an amount of liquid particles 342. In other
embodiments, the baffles 228 can be more or less parabolic. One of
ordinary skill in the art can appreciate the multitude of different
baffle shapes for retarding the evacuation of liquid relative to
the evacuation of air or other gases.
[0052] It is understood that the trapping of liquid in baffles or
vessels formed in the bag is advantageous as this structure retards
and prevents liquids from being drawn into the vacuum pump or
suction device of a vacuum sealing tool such as disclosed in U.S.
Pat. No. 4,941,310, which is incorporated herein by reference.
[0053] FIG. 4 illustrates a bag for use in vacuum packaging in
accordance with one embodiment of the present invention. The vacuum
bag 450 comprises a first panel 452 and a second panel 454
overlapping each other. Channels 224 are formed on at least one of
the panels 452,454 in accordance with an embodiment described
above. The heat-sealable inner layer 106 and the gas-impermeable
base layer 108 of the first and second panels 452,454 are typically
made of the same material respectively, but can alternatively be
made of different materials that exhibit heat-sealability and
gas-impermeability respectively. As described above, the
resin-formed layer 106 is used as an inner layer and the
gas-impermeable base layer 108 is used as an outer layer. The
lower, left, and right edges of the first and the second panel
452,454 are bonded to each other by heating, so as to form an
envelope for receiving a perishable or other product to be vacuum
packaged. Once a perishable or other product is placed in the
vacuum bag 450, air and/or other gases can be evacuated from the
bag 450, for example by a vacuum sealing machine as described in
the above referenced U.S. Pat. No. 4,941,310, which is incorporated
herein by reference. Once the air and/or other gases are evacuated
to the satisfaction of the user, the inlet can be sealed by
applying heat, thereby activating the heat-sealable inner layers
106 and bonding them together where contacted by the heat.
[0054] The foregoing description of preferred embodiments of the
present invention has been provided for the purposes of
illustration and description. It is not intended to be exhaustive
or to limit the invention to the precise forms disclosed. It is to
be understood that many modifications and variations will be
apparent to the practitioner skilled in the art. The embodiments
were chosen and described in order to best explain the principles
of the invention and its practical application, thereby enabling
others skilled in the art to understand the invention for various
embodiments and with various modifications that are suited to the
particular use contemplated. It is intended that the scope of the
invention be defined by the following claims and their
equivalence.
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