US20040234171A1

US20040234171A1 - Reclosable pouch with closure device that allows venting and/or an air-tight seal

Info

Publication number: US20040234171A1
Application number: US10/440,822
Authority: US
Inventors: Brian Dais; James Pawloski; John Trent
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-05-19
Filing date: 2003-05-19
Publication date: 2004-11-25
Also published as: CL2004001134A1; TW200508103A; PE20050384A1; AR044766A1; US20040234173A1

Abstract

A reclosable pouch includes a body portion having first and second opposing bag walls, wherein each bag wall has an internal side. First and second closure mechanisms are disposed on the internal sides of the first and second bag walls, wherein the closure mechanisms are parallel to one another and spaced apart between about 0.3 inch (7.62 mm) and about 0.6 inch (15.24 mm). The pouch further includes a venting mechanism.

Description

TECHNICAL FIELD

The present invention relates to closures for reclosable pouches, and more particularly, to such closures that allow a user to form a vented pouch or an air-tight pouch.

BACKGROUND ART

A thermoplastic bag for the storage of items typically includes a closure mechanism comprising male and female closure elements or profiles attached to an inner surface of a bag wall. In addition, thermoplastic bags are known having one or more pairs of ribs on outer surface(s) of the bag wall straddling at least one of the closure elements to guide a user's fingers when sealing the closure elements. Ribs have also been used on an internal surface of the thermoplastic bag closely spaced and adjacent the closure elements to assist in aligning the male and female closure elements when sealing the bag. Bags have also been developed that allow air or other gas transport through bag walls.

Hugues et al., U.S. Pat. No. 4,672,723 discloses a stabilized reclosable extruded plastic fastener. The fastener comprises a female profile on one wall of an extruded film material and a male profile on an opposite wall of the film material. Alignment ribs are spaced alongside and integral with a base area of the male profile to facilitate alignment of the male profile with the female profile during closing of the fastener.

Fisher, U.S. Pat. No. 4,736,496, owned by the assignee of the present application, discloses a wide-track integral thermoplastic closure for a reclosable thermoplastic container. The closure includes ribs on either side of an element of the closure to assist in guiding a user's fingers during closure of the thermoplastic container.

Tilman et al., U.S. Pat. No. 4,929,487 discloses a thermoplastic bag having male and female fastener profiles and at least one alignment rib integral with the film and disposed on an outer surface of a bag wall opposite and aligned with the male profile. The rib functions to stiffen the area of film occupied by the male profile and facilitate the alignment of the male and female fastener profiles.

Porchia et al., U.S. Pat. No. 5,012,561, also owned by the assignee of the present application, discloses a closure for reclosable thermoplastic containers. The closure comprises male and female closure elements, wherein the male closure element includes a male profile member and ribs disposed on either side of the male profile member and attached thereto by a base. The ribs are of a sufficient size and proximity to the male profile member so as to move together as a unit with the male profile member when the male and female closure elements are engaged or disengaged.

Dais et al., U.S. Pat. No. 5,140,727, owned by the assignee of the present application, discloses a zipper for reclosable thermoplastic bags and a process and apparatus for making the same. The zipper comprises opposing longitudinally extending interlockable rib and groove profiles. The rib profile defines a bulbous head that is generally triangularly shaped in cross-section, a stem, and optionally, one or more ribs adjacent the stem.

Tilman, U.S. Pat. No. 5,209,574 discloses a reclosable plastic bag having a sliderless zipper. The bag includes front and rear walls sealed along three edges to form a mouth or opening. Male and female profiles are attached to internal surfaces of the front and rear walls, respectively, wherein the male and female profiles are engageable to close the opening. Two ribs are provided on an outside surface of the front wall, one on each side of the male profile, to define a valley therebetween. Similarly, two additional ribs are formed on the outside surface of the rear wall, one on each side of female profile, to define a valley therebetween. The valleys act as finger guides for the user of the bag.

Scott et al., U.S. Pat. No. 5,368,394 discloses a reclosable bag having a stabilizer wedge zipper. The reclosable bag comprises front and rear walls sealed along three edges to form an opening. Male and female profiles are attached to internal faces of the walls. Each of the male and female profiles includes two stabilizer wedges that assist in transmitting forces to male and female profiles during opening of the bag.

Porchia et al., U.S. Pat. No. 5,492,705, owned by the assignee of the present application, discloses a flexible film for storage bags used for packaging produce, such as vegetables and fruits. The film includes a plurality of holes therein to allow air transport through the film so that the produce can breathe at a controlled rate.

Saad et al., U.S. Pat. No. 5,804,265, also owned by the assignee of the present application, discloses a multilayer freezer bag having at least an inner liner bag and an outer support bag. The inner liner bag and/or the outer support bag may include a plurality of holes through sidewalls thereof.

Tilman, U.S. Pat. No. 6,231,236 discloses a resealable package having a venting structure. The package includes first and second reclosable closure mechanisms disposed at an end of the package, wherein the first closure mechanism is disposed between the second closure mechanism and the end of the package. The venting structure defines a gas-flow passageway between an interior of the package and an exterior of the package when the first closure mechanism is in a closed configuration and the second closure mechanism is in an open configuration.

Nelson, U.S. Patent Application Publication No. 2003/0066267 discloses a reclosable bag with a closure having extruded male and female interlocking profiles extending along opposite sides of an opening of the bag. The closure further includes an extruded valve flange extending from one side of the closure to engage an opposing surface of the closure. One or more vent passages are disposed between the interlocking profiles and the valve flange or the female profile is segmented to allow air to escape from the bag.

Other thermoplastic bags have been developed having spaced multiple closure mechanisms. For example, a bag manufactured by Thai Griptech Company, Ltd. of Bangkok, Thailand, includes first and second spaced closure mechanisms disposed at a top portion of the bag. Each closure mechanism includes a male closure portion and a female closure portion, wherein the male closure portions are disposed on a first bag wall and the female closure portions are disposed on a second bag wall opposite the male closure portions. The first closure mechanism is disposed approximately {fraction (3/8)}ths inch from the second closure mechanism.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a reclosable pouch includes a body portion having first and second opposing bag walls, wherein each bag wall has an internal side. The pouch further includes first and second closure mechanisms disposed on the internal sides of the first and second bag walls, wherein the closure mechanisms are parallel to one another and spaced apart between about 0.2 inch (5.08 mm) and about 0.5 inch (12.7 mm). Still further, the pouch includes a venting mechanism.

According to another aspect of the present invention, a reclosable pouch includes a body portion having first and second opposing bag walls, wherein each bag wall has an internal side. The pouch further includes first and second closure mechanisms disposed on the internal sides of the first and second bag walls, wherein the closure mechanisms are parallel to one another. Still further, the pouch includes a plurality of holes extending through at least one of the first and second bag walls between the first and second closure mechanisms.

According to yet another aspect of the present invention, a method of enclosing a space includes the step of providing a reclosable pouch having first and second closure mechanisms disposed on internal sides of the first and second bag walls and a venting mechanism. The method further includes the steps of sealing the first closure mechanism to define a space within the pouch, causing air flow through the venting mechanism, and optionally closing the second closure mechanism.

Other aspects and advantages of the present invention will become apparent upon consideration of the following detailed description and the attached drawings, in which like elements are assigned like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevational view of a reclosable thermoplastic storage bag according to the present invention; [0019]
FIG. 2 is an enlarged, fragmentary, sectional view taken generally along the lines [0020] 2-2 of FIG. 1;
FIGS. 3 and 4 are views similar to FIG. 2 illustrating alternative closure mechanisms of the present invention; [0021]
FIG. 5 is an elevational view of a reclosable thermoplastic storage bag with a first embodiment of a venting mechanism according to the present invention; [0022]
FIG. 6 is an enlarged, fragmentary, sectional view taken generally along the lines [0023] 6-6 of FIG. 5;
FIGS. 7A-7D are fragmentary isometric views of alternative embodiments of closure mechanisms including venting mechanisms of the present invention; [0024]
FIGS. 8A and 8B are fragmentary sectional views similar to FIG. 2 of alternative embodiments of closure mechanisms including venting mechanisms of the present invention; [0025]
FIGS. 8C and 8D are enlarged, fragmentary, sectional views taken generally along the [0026] lines 8C-8C and 8D-8D, respectively, of FIG. 5;
FIG. 9 is an isometric view of an apparatus for producing bags of the present invention; [0027]
FIG. 10 is an enlarged, fragmentary isometric view of a portion of the apparatus of FIG. 9; [0028]
FIG. 11 is an enlarged end elevational view of the apparatus of FIGS. 9 and 10; and [0029]
FIG. 12 is a diagrammatic isometric view of an extrusion apparatus for extruding zipper tape incorporating the present invention.[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, a reclosable pouch in the form of a [0031] thermoplastic storage bag 20 comprises first and second body portions 22, 24 joined to one another to form first and second bag walls 26, 28. The first and second bag walls 26, 28 are joined at first and second side portions 30, 32, respectively, and at a bottom portion 34. An opening 35 is disposed at a top portion 36 of the bag 20. First and second closure mechanisms 38 a, 38 b and two lips 40 are also disposed at the top portion 36 of the bag 20. The first closure mechanism 38 a is disposed between the second closure mechanism 38 b and an upper edge 42 of the top portion 36.
Referring to FIG. 2, male and female closure elements or [0032] portions 44 a, 44 b of the closure mechanism 38 a are disposed on opposing internal sides or surfaces 46, 48 of the first and second body portions 22, 24, respectively. In addition, male and female elements or portions 50 a, 50 b of the closure mechanism 38 b are disposed on the internal sides or surfaces 48, 46, respectively. Preferably, although not necessarily, the closure mechanism 38 a is parallel to the closure mechanism 38 b and the two are spaced from one another by a distance that is sufficiently large to allow each of the closure mechanisms to be individually opened or closed, but still optionally allow the closure mechanisms to be opened and closed simultaneously. Typically, these results are accomplished by spacing the mechanisms 38 a, 38 b between about 0.2 inch (5.08 mm) and about 0.8 inch (20.32 mm) apart, more preferably between about 0.3 inch (7.62 mm) and about 0.6 inch (15.24 mm) and, most preferably, about 0.4 inch (10.16 mm), although a different spacing may instead be used.
Preferably, the closure elements or [0033] portions 44 a, 44 b, 50 a, and 50 b have a cross sectional shape and/or may be formed in accordance with the teachings of Geiger, et al. U.S. Pat. No. 4,755,248, Zieke et al., U.S. Pat. No. 4,741,789, and/or Porchia et al., U.S. Pat. No. 5,012,561, owned by the assignee of the present application and the disclosures of which are hereby incorporated by reference herein. Optionally, the first closure mechanism 38 a exhibits a first closure characteristic and the second closure mechanism 38 b exhibits a second closure characteristic different than the first closure characteristic. For example, either or both of the first and second closure mechanisms 38 may exhibit a relatively low level of resistance to bag opening forces but provide a high level of deformation so as to exhibit a clicking feel and/or sound when the bag is opened or closed. In addition, either or both of the first and second closure mechanisms 38 may exhibit a low level of deformation but provide a relatively high overall resistance to bag opening forces. Either or both of the male closure elements 44 a, 50 a may be symmetric or asymmetric about a longitudinal centerline thereof and either or both of the female closure elements 44 b, 50 b may be symmetric or asymmetric about a longitudinal centerline thereof. Thus, for example, either or both of the first and second closure mechanisms 38 may have an asymmetric configuration so that the closure mechanism 38 exhibits a first resistance to opening forces exerted on one side of the mechanism 38 and further exhibits a second, different resistance to opening forces exerted on another side of the mechanism 38.
FIG. 3 illustrates a further embodiment wherein like reference numbers denote structures common to the various embodiments. As seen in FIG. 3, the [0034] male closure elements 44 a and 50 a are disposed on the internal side or surface 46 and the female closure elements 44 b and 50 b are disposed on the internal side or surface 48.
As seen in FIG. 3, each [0035] male closure element 44 a, 50 a comprises an arrow-shaped engagement member 80, 82, respectively, and a base member 84, 86, respectively. Each female closure element 44 b, 50 b comprises a C-shaped profile member 90, 92, respectively, joined to base members 94, 96, respectively. The base members 84, 86 are only slightly wider than the engagement members 80, 82 and the base members 94, 96 are only slightly wider than the side-to-side extent (as seen in FIG. 3) of the C-shaped profile members 90 and 92. The same is true of the embodiment of FIG. 2. In both of these embodiments relatively little resin is required to form the closure mechanisms 38. In fact, it is believed that only a minimal increase in resin is needed to produce the closure elements 38 compared to a standard bag design utilizing a single closure mechanism.
FIG. 4 illustrates yet another embodiment of the present invention wherein the [0036] closure mechanisms 38 a, 38 b are replaced by closure mechanisms 138 a, 138 b. The mechanism 138 a includes male and female closure elements 144 a, 144 b and the mechanism 138 b includes male and female closure elements 150 a, 150 b. The mechanisms 138 a, 138 b are identical, and hence, only the closure mechanism 138 a will be discussed in detail. The male closure element 144 a of the closure mechanism 138 a comprises a base 154 integral with flanking side members 156 and 158 and an arrow-shaped engagement member 160 that extends from the base 154. A female closure element 144 b comprises a base 162 with a C-shaped profile member 164 extending therefrom, wherein the female closure element 144 b is adapted to receive the male closure element 144 a when pressure is exerted on the closure elements by a user's finger(s) during closing of the bag. The side members 156 and 158 are of a sufficient size and proximity to the engagement member 160 such that the side members 156 and 158 move together with the member 160 when the members 160 and 164 are engaged and disengaged. The side members 156 and 158 also have a height that is less than the height of the engagement member 160, and the members 156 and 158 extend beyond tips 168 of the female profile member 164 when the engagement member 160 is engaged with the female profile member 164. Thus, at such time, the tips 168 of the female profile member 164 reside between the side members 156 and 158 and the male engagement member 160.
As in the previous embodiments, the [0037] male closure elements 144 a, 150 a may be disposed on the same bag wall or on different bag walls, as may the female closure elements 144 b, 150 b.
As should be evident by a comparison of FIGS. 3 and 4, the [0038] base members 84, 86, 94, and 96 of FIG. 3 are replaced by elongate members 180, 182, 184, 186, respectively, and hence, more resin is required to produce the closure mechanisms 138 a, 138 b as compared to the closure mechanisms 38 a, 38 b. However, the elongate members 180-186 further promote guiding of the user's fingers and thumb during closing of the respective closure mechanism.
FIGS. 5 and 6 show a first embodiment of the venting mechanism of the present invention. The [0039] closure mechanisms 38 a, 38 b of FIGS. 5 and 6 may be identical or similar to any of the closure elements described above. The venting mechanism includes a plurality of holes 188 disposed in at least one of the first and second bag walls 26, 28 between the male and female closure elements 44 a, 44 b of the closure mechanism 38 a and the male and female closure elements 50 a, 50 b of the closure mechanism 38 b. The venting mechanism includes between about 1 hole and about 1000 holes per bag, and more preferably between about 10 holes and about 100 holes per bag, whether the hole(s) are disposed in a single bag wall between the closure mechanisms 38 a, 38 b or both bag walls. The diameter of the holes is between about 0.001 inch (0.0254 mm) and about 0.5 inch (12.7 mm), and more preferably between about 0.05 inch (1.27 mm) and about 0.2 inch (5.08 mm). The holes may be spaced randomly or in a pattern, but preferably are spaced in a line across a width of the bag 20.
To utilize a plurality of holes as a venting mechanism, a user may place produce or another product in an interior of the [0040] pouch 190 and seal the closure mechanism 38 a, such that there is air communication between the interior of the pouch 190 and an exterior of the pouch 192 through the holes 188. If desired, the user may vent air in the pouch 192 outwardly through the holes 188 by squeezing the pouch 192. If the pouch is not to be made air tight, the closure mechanism 38 b may be left non-occluded. Alternatively, if the user desires an air-tight pouch, the user may place a product in the interior of the pouch 190, seal the closure mechanism 38 a, force any air in the interior of the pouch 190 out through the holes 188 in the manner noted above, and seal the closure mechanism 38 b. Optionally, the user may place a product in the interior of the pouch 190, seal the closure mechanism 38 b, and occlude or not occlude the closure mechanism 38 a.
Further embodiments of the venting mechanism of the present invention are shown in FIGS. 7A-7D. In these embodiments, one or both of the male or female closure elements of either of the [0041] closure mechanisms 38 a or 38 b is segmented to allow passage of fluid, air, or another gas or gases therethrough. As seen in FIG. 7A, the male closure element 44 a of the closure mechanism 38 a is segmented and the female closure element 44 b is solid. Conversely, in FIG. 7B, the female closure element 44 b of the closure mechanism 38 a is segmented and the male closure element 44 a is not. In either case, if the user prefers to utilize the venting mechanism, the user would place a product in an interior of the pouch 190 and occlude the closure mechanism 38 a, thus capturing the product in the interior of the pouch 190 but allowing fluid communication between the interior of the pouch 190 and the exterior of the pouch 190 through the segmented closure element, whether it is the male or female closure element. To utilize the pouch as an air-tight pouch, the user may place a product in the pouch and seal the closure mechanism 38 b either with or without occluding the closure mechanism 38 a.
Optionally, as seen in FIG. 7C, the [0042] male closure element 50 a of the closure mechanism 38 b is segmented and the female closure element 50 b is not. FIG. 7D further depicts the female closure element 50 b of the closure mechanism 38 b being segmented and the male closure element 50 a being non-segmented. Either way, in order to utilize the venting mechanism, the user may place the product in the interior of the pouch 190 and occlude the closure mechanism 38 b. To create an air-tight pouch, the user may optionally force any excess air from the pouch interior 190 out through the segmented closure mechanism 38 b and seal the closure mechanism 38 a. Alternatively, the user may simply place a product in the interior of the pouch 190 and seal the closure mechanism 38 a. The segmentation of FIGS. 7A-7D may be utilized with any closure element disclosed herein or any other type of closure mechanism.
Depending on the use for the pouch, the [0043] closure mechanism 38 a may also have male and female closure elements 44 a, 44 b that are both segmented and/or the closure mechanism 38 b may have both male and female closure elements 50 a, 50 b that are segmented.
Alternative embodiments of the venting mechanism of the present invention are shown in FIGS. 8A-8D. In each of these embodiments one or both of the [0044] closure mechanisms 138 has either a deformed male closure member 189 b or a deformed female closure member 189 a. As seen in FIG. 8A, the female closure member 189 a has been modified by increasing the side-to-side distance between opposed tips 168 of the female profile member 164 and/or the male closure member 160 has been modified by narrowing the side-to-side thickness of a stem portion 167 thereof. Either modification may be accomplished by removing or deforming material either during or after the extrusion process. In any event, one or more spaces or gaps are interposed between the tips 168 of the female profile member 164 and the stem portion 167 when the closure members 189 a, 189 b are occluded. Fluid, air, or another gas may pass through the gaps as desired. In another embodiment, the male arrow-shaped profile member 160, as seen in FIG. 8B, may be deformed by displacing and/or removing portions thereof to create at least one gap that permits fluid communication from one lateral side of the closure element to an opposite lateral side of the closure element. More generally, one aspect of the present invention comprehends the formation or creation of a gap or other passage between the male and female closure members that allows fluid communication from one side of a closure mechanism 138 to another side of the closure mechanism 138. As a further example, the embodiment of FIGS. 8C and 8D includes at least one closure mechanism 138 having a gap 169 a between one of the tips 168 of the female profile member 164 and the stem 167 of the male arrow-shaped profile member 160 at a first location across the width of the closure mechanism 138 (seen in FIG. 8C). The closure mechanism(s) 138 may further include another gap 169 b between the other of the tips 168 of the female profile member 164 and the stem 167 at a second location across the width of the closure mechanism 138 (FIG. 8D). Fluid communication is provided between the gaps 169 a, 169 b due to a space 170 that exists between the external surfaces of the male profile member and the internal surfaces of the female profile member. If desirable or necessary, additional gaps similar or identical to the gaps 169 may be provided at other locations along the width of the pouch. The fluid communication across the closure element(s) 138 allows slow leaking of air through the profiles, therefore allowing some ventilation in the pouch.
In any of the embodiments disclosed herein, one or more gripping ribs (not shown) may be disposed on the [0045] internal surfaces 46, 48 of the bag 20 between the closure mechanisms 38 a and 38 b and the top portion 36 of the bag 20, wherein the gripping ribs are integrally extruded with the walls of the bag. Any number of gripping ribs can be used, although space is necessary between adjacent ribs in order to facilitate a gripping action with a user's fingers. In a preferred embodiment, about six or seven gripping ribs are disposed on each lip 40 of the bag.
Reclosable thermoplastic storage bags as described herein can be produced by any suitable bag-making process, such as a cast post applied process, a cast integral process, a blown process or any other process known in the art. It should be noted that the extrusion die(s) used to form the closure mechanisms and strip(s) must include a suitable number of profile plates to form such structures. In addition, an air nozzle may be provided in association with each female closure element that blows air into the opening of each C-shaped female profile member to open the member as it is being extruded. The air flow and/or velocity may be varied to obtain the desired deformation for venting purposes, as noted above. In addition, one or more cooling water jets may be provided to cool the male and female closure elements after they are extruded. [0046]
If desired, an alternative post applied process can be used to produce any of the bags disclosed herein, such as seen in FIGS. 9 and 10. Referring to such FIGS., the alternative post applied process utilizes an extrusion apparatus including a first extrusion slot die [0047] 289, a temperature-controlled driven casting roll 290, edge pinning devices or apparatus 292 a, 292 b, an air knife 294, second and third extrusion dies 296 a, 296 b (that are diagrammatically shown and which, together with the die 189, form the extrusion apparatus) and blowing apparatus 298 a, 298 b. The extrusion die 289 receives molten thermoplastic from an extruder (not shown) and deposits the thermoplastic in sheet form as a web 300 onto the casting roll 290. The extrusion die 289 includes a slot opening (not shown) that forms thickened areas 302, 304 at outside edge portions 306 a, 306 b of the resulting web 300 and a relatively thinner portion 308 intermediate the thickened areas 302, 304. The edge portions 306 a, 306 b are pinned to the casting roll 290 by the edge pinning devices 292 a, 292 b, respectively. The web 300 is then pinned across the entire width thereof (i.e., as a whole) to the casting roll 290 by the air knife 294.
After the [0048] web 300 is pinned to the casting roll 290, the male and female closure elements 44, 50 or 144, 150 are formed on the web 300. Preferably, the extrusion dies 296 a, 296 b receive molten thermoplastic from separate extruders and extrude the male and female closure elements 44, 50 or 144, 150 onto the thickened areas 302, 304. Alternatively, the separate extrusion dies 296 a, 296 b may be replaced by a single extrusion die having two outlets at which the male and female closure elements 44, 50 or 144, 150 are simultaneously extruded onto the thickened areas 302, 304. As a still further alternative, each extrusion die 296 a, 296 b may be replaced by two or more extrusion dies that individually and separately extrude the closure elements 44, 50 or 144, 150. In any event, as seen in FIG. 11, the angle of a face 310 of each die 296 is at least initially disposed substantially parallel to a horizontal (as seen in FIG. 11) radial line 311 extending from the center of the casting roll 290. The position of the die 196 (or each die 296 a, 296 b individually if separate dies are used) may then be adjusted by moving the die left, right, up, or down (all as seen in FIG. 11) or the die may be tipped (i.e., angularly displaced) to adjust the angle of the die face 210 to obtain desirable results. The closure elements 44, 50 or 144, 150 formed by the die(s) 296 may exit the die(s) 296 at a point coincident with a vertical tangent line 312 (FIG. 11) intersecting the surface of the casting roll 290 on the side of the casting roll 290 where the web 300 is first deposited thereon. Alternatively, the closure elements 44, 50 or 144, 150 formed by the die(s) 296 may exit the die(s) 296 at a point displaced to the right or left (as seen in FIG. 11) of the tangent line 312. If the extrudate exits the die(s) 296 at a point displaced to the right of the line 312, some provision must be made at the initiation of production to attach the extrudate stream to the casting roll 290. Thereafter, production may commence, (provided that the exit of the die(s) 296 is not disposed too far to the right of the tangent line 312) whereupon the melt strength of the extrude stream carries the stream into contact with the roll 290.
Once the molten thermoplastic from the die(s) [0049] 296 has been deposited onto the web 300, coolant is applied to the closure elements 44, 50 or 144, 150 by coolant apparatus (not shown) to bring the temperature thereof below the melting point of the thermoplastic material forming the closure elements 44, 50 or 144, 150 as quickly as possible. Preferably, the coolant comprises water or any other suitable cooling fluid and the coolant is applied to the material of the closure elements 44, 50 or 144, 150 only after such material contacts the material of the web 300 so that adhesion thereto is optimized. The web 300 and the closure elements 44, 50 or 144, 150 are maintained in contact with the temperature-controlled casting roll 290 for a period of time as the roll 290 is rotated so that the web 300 and closure elements 44, 50 or 144, 150 are further cooled. The casting roll 290 should be maintained at a temperature below the melting point of the thermoplastic material(s) forming the web 300 and the closure elements 44, 50 or 144, 150, typically about 20-80 degrees C.
If desired, any of the closure elements and/or strips and/or other associated structures of the above embodiments can be integrally extruded on internal surfaces of flanges as zipper tape that is subsequently post-applied to film in a bag production process. For example, the closure elements [0050] 44, 50 or 144, 150 may be extruded with flanges as zipper tape portions 400, 402. In this embodiment, gripping ribs may also be formed on the zipper tape and the zipper tape may have relatively thicker portions at portions that ultimately form the top of the bag and relatively thinner portions at opposite portions where the zipper tape is to be joined to the film. For example, as seen in FIG. 12, zipper tape portions 400, 402 may be extruded separately by an extrusion die 404 into a water bath 406. If desired, more than one extrusion die may be employed for this purpose. The zipper tape portions 400, 402 extend about pulleys or rollers 408, 410, respectively, in the water bath 306 and may further extend about additional pulleys or rollers 412, 414 and 416, 318 out of the water bath 406. The zipper tape portions 400, 402 may thereafter pass through a dewatering station 420, where the water is removed therefrom, and the portions 400, 402 may be joined together (i.e., occluded) by nip rollers 422. The occluded portions 400, 402 may thereafter be stored on spools or reels or the occluded portions may be directly delivered to an in-line bag manufacturing apparatus, where the portions 400, 402 are laminated or otherwise secured to bag film.
During or after the use of any suitable bag-making process to create pouches or partial pouches, holes may be created in the pouches between the [0051] closure mechanisms 38 a, 38 b by any means known in the art. Such processes include punching, using lasers, burning holes in the thermoplastic with hot pins or needles, perforating, utilizing high pressure water jets, or using electrical arcs to create holes therein. Some of these processes are disclosed in detail in Dais et al., U.S. Pat. No. 5,405,561, owned by the assignee of the present application and the disclosure of which is hereby incorporated by reference herein.
Alternatively, during or after the use of any suitable bag-making process to create pouches or bags, any of the closure elements may be segmented or deformed. Segmentation and deformation may be created using a lateral punching means or a deforming apparatus, respectively, as disclosed in Dais et al., U.S. Pat. No. 5,140,727, owned by the assignee of the present application and the disclosure of which is hereby incorporated by reference herein. Optionally, deformation may be created by pulsing the extruder during extrusion of any of the closure elements or forcing water from a water jet onto any of the closure elements after extrusion thereof to effect deformation. [0052]

INDUSTRIAL APPLICABILITY

The pouch described herein advantageously can have an air-tight seal for products that should not be in substantial contact with air during storage thereof or can have a vented seal for products, such as fruits and vegetables, that are best stored in a manner that allows air and water vapor to circulate through the bag walls. In addition, the bag can be used to permit product stored therein to be treated with a gas before storage of the product. Still further, the pouch may also permit venting of steam when microwaving foods therein or to simply remove all excess air from the pouch prior to air tight sealing thereof. [0053]
The pouch of the present invention is provided with two closure mechanisms spaced apart a distance far enough wherein each closure mechanism can be sealed and unsealed individually or simultaneously. A venting mechanism is provided in the pouch either by disposing holes between the closure mechanisms, segmenting one or more of the closure elements of one or more of the closure mechanisms, or deforming one or more of the closure elements of one or more of the closure mechanisms. [0054]
Numerous modifications will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is presented for the purpose of enabling those skilled in the art to make and use the invention and to teach the best mode of carrying out same. The exclusive rights to all modifications which come within the scope of the appended claims are reserved. [0055]

Claims

We claim:

1. A reclosable pouch, comprising:

a body portion having first and second opposing bag walls, wherein each bag wall has an internal side;

first and second closure mechanisms disposed on the internal sides of the first and second bag walls, wherein the closure mechanisms are parallel to one another and spaced apart between about 0.3 inch (7.62 mm) and about 0.6 inch (15.24 mm); and

a venting mechanism.

2. The reclosable pouch of claim 1, wherein the first closure mechanism is disposed between the second closure mechanism and an opening of the pouch.

3. The reclosable pouch of claim 2, wherein each of the closure mechanisms includes a male profile and a female profile.

4. The reclosable pouch of claim 3, wherein the venting mechanism includes a deformed male profile of the second closure mechanism.

5. The reclosable pouch of claim 3, wherein the venting mechanism includes a deformed female profile of the second closure mechanism.

6. The reclosable pouch of claim 3, wherein the venting mechanism includes a deformed male profile of the first closure mechanism.

7. The reclosable pouch of claim 3, wherein the venting mechanism includes a deformed female profile of the second closure mechanism.

8. The reclosable pouch of claim 3, wherein the venting mechanism comprises a segmented male profile of the second closure mechanism.

9. The reclosable pouch of claim 3, wherein the venting mechanism comprises a segmented female profile of the second closure mechanism.

10. The reclosable pouch of claim 3, wherein the venting mechanism comprises a segmented male profile of the first closure mechanism.

11. The reclosable pouch of claim 3, wherein the venting mechanism comprises a segmented female profile of the first closure mechanism.

12. The reclosable pouch of claim 3, wherein the venting mechanism includes a plurality of holes disposed in one of the first and second bag walls between the first and second closure mechanisms.

13. The reclosable pouch of claim 12, wherein the holes have diameters between about 0.001 inch (0.0254 mm) and about 0.5 inch (12.7 mm).

14. The reclosable pouch of claim 3, wherein the venting mechanism includes a plurality of holes disposed in both of the first and second bag walls between the first and second closure mechanisms.

15. The reclosable pouch of claim 14, wherein the holes have diameters between about 0.001 inch (0.0254 mm) and about 0.5 inch (12.7 mm).

16. A reclosable pouch, comprising:

first and second closure mechanisms disposed on the internal sides of the first and second bag walls, wherein the closure mechanisms are parallel to one another; and

a plurality of holes extending through at least one of the first and second bag walls between the first and second closure mechanisms.

17. The reclosable pouch of claim 16, wherein the holes have diameters of between about 0.001 inch (0.0254 mm) and about 0.5 inch (12.7 mm).

18. The reclosable pouch of claim 16, wherein between about 1 and about 1000 holes are disposed in the bag walls.

19. The reclosable pouch of claim 16, wherein the first closure mechanism is disposed above the second closure mechanism.

20. The reclosable pouch of claim 19, wherein sealing the first closure mechanism creates a reclosable pouch with fluid communication between an inside of the pouch and an outside of the pouch.

21. The reclosable pouch of claim 19, wherein sealing the second closure mechanism creates a reclosable pouch with no fluid communication between an inside of the pouch and an outside of the pouch.

22. A method of enclosing a space, the method comprising the steps of:

providing a reclosable pouch having first and second closure mechanisms disposed on internal sides of the first and second bag walls and a venting mechanism;

sealing the first closure mechanism to define a space within the pouch;

causing air flow through the venting mechanism; and

optionally closing the second closure mechanism.

23. The method of claim 22, wherein the first closure mechanism is disposed between an opening of the pouch and the second closure mechanism.

24. The method of claim 23, wherein the method further includes introducing product into the pouch before sealing the first closure mechanism.

25. The method of claim 23, wherein the venting mechanism includes holes disposed between the first and second closure mechanisms.

26. The method of claim 23, wherein the venting mechanism includes a segmented female closure element of the first closure mechanism.

27. The method of claim 23, wherein the venting mechanism includes a segmented male closure element of the first closure mechanism.

28. The method of claim 23, wherein the venting mechanism includes a segmented female closure element of the second closure mechanism.

29. The method of claim 23, wherein the venting mechanism includes a segmented male closure element of the second closure mechanism.

30. The method of claim 23, wherein the venting mechanism includes a deformed female closure element of the first closure mechanism.

31. The method of claim 23, wherein the venting mechanism includes a deformed male closure element of the first closure mechanism.

32. The method of claim 23, wherein the venting mechanism includes a deformed female closure element of the second closure mechanism.

33. The method of claim 23, wherein the venting mechanism includes a deformed male closure element of the second closure mechanism.

34. The method of claim 22, wherein the method further includes the step of forcing air out of the pouch through the venting mechanism.

35. The method of claim 34, wherein the method further includes the step of sealing the second closure mechanism to seal the space inside the pouch.

36. The method of claim 35, wherein the method further includes the step of introducing product into the pouch before sealing the first closure mechanism.

37. The method of claim 23, wherein the method further includes the step of forcing air out of the pouch through the venting mechanism.

38. The method of claim 37, wherein the method further includes the step of sealing the second closure mechanism to seal the space inside the pouch.

39. The method of claim 38, wherein the method further includes the step of introducing product into the pouch before sealing the first closure mechanism.

40. The method of claim 22, wherein the method further includes the step of introducing product into the pouch before sealing the first closure mechanism.