WO1999054214A1

WO1999054214A1 - Sealable containers and method of forming containers

Info

Publication number: WO1999054214A1
Application number: PCT/US1999/007379
Authority: WO
Inventors: William S. Black; Ra'ed S. Al-Zubi
Original assignee: Box-Ease International, Inc.
Priority date: 1998-04-23
Filing date: 1999-04-23
Publication date: 1999-10-28

Abstract

Sealable containers (10) of supple plastic material are capable of self-support and can be collapsed for compact shipping and storage. The containers (10) may be packaged in a collapsed configuration and may be returned to a self-standing position for ingress of materials to be stored in the containers (10). A method of making the containers may include forming a bend (20c) in a zipper-type closure device (20) such that the zipper-type closure device (20) can be attached to multiple sides (22) of the container body (16) and lid (18). Also included in the method may be a manner of attaching the zippers (20) to the lid (18) or body (16) of the container (10). The body (16) may be thermoformed and the lid (18) permanently attached to the body (16) as part of the method.

Description

SEALABLE CONTAINERS AND METHOD OF FORMING CONTAINERS

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to packaging products and methods of making, packaging, and dispensing the packaging products, more specifically sealable packaging products and efficient manners of forming, packaging, and dispensing the sealable packaging products.

2. Prior State of the Art

Packaging products are indispensable to our present consumer-oriented society. Packaging products free people from mundane tasks such as daily shopping for fresh food. They also make consumer goods more conveniently accessible and help lower the cost of these goods. Many of the items and much of the food consumed today are perishable and require containment against contamination from and leakage into the outside environment. Virtually all products sold to consumers necessitate convenient methods of bundling, transporting, storing, and displaying. As a consequence, the majority of food and other items presently consumed come packaged in one form or another.

One of the primary objects of our increasingly service oriented economy is providing convenience to the consumer. In the packaging industry this translates to providing effective, inexpensive, and flexible packaging products. Some packaging products that currently offer a high level of convenience include home packaging and repackaging products such as disposable plastic storage bags and hard sided plastic containers. Even these convenience oriented products are in need of improvement, however, as will be discussed.

Plastic storage bags are inexpensive, air-tight, and are often used for applications such as storing and preserving frozen foods, sandwiches, and leftovers. They provide a great advantage in that they are disposable. They also take up a minimum of storage space when empty. One convenient addition to plastic storage bags is the zipper-type closure device along the opening or mouth of the bag. These zipper-type bags provide a high degree of the convenience that modern day consumers demand, but they do have certain disadvantages. For instance, zipper-type bags are difficult to stack as they are incapable of retaining their shape when filled, and they are incapable of standing on their own. They cannot be placed on a surface with their contents exposed, making them inadequate for microwave cooking, another convenience desired by modern day consumers. They are also not well suited for containing liquid materials. Additionally, filling plastic bags is inconvenient and requires pulling the bag out of a box, opening the bag, then holding the sides of the bag open while filling it This process can be time consuming, especially when used for multiple filling operations

Hard sided containers stand by themselves, can be reused, and are easy to fill The contents can be stirred, heated, and otherwise accessed with the top off Nevertheless, hard sided containers are quite bulky and take up a large amount of storage space, especially when the containers are of large volume In addition, the lids to hard sided containers are often lost or misplaced, making proper or complete use of the hard sided containers difficult

Another example of packaging upon which consumers rely for convenience is the grocery bag Paper grocery bags are self-standing and much easier to fill than the plastic bags discussed above, but they are not sealable and cannot be used to contain perishable items over long periods of time Furthermore, when opening such bags, one is required to undertake the time consuming procedure of removing a bag from a stack, opening the bag by holding it apart with one hand while thrusting the other hand into the bag, or gripping an edge portion thereof, followed by quickly moving the bag through the air causing air to enter the bag for the opening thereof Plastic bags have also been used as grocery bags, and are desirable in that they are less expensive to produce The main disadvantage of plastic bags is that they generally cannot maintain a standing position on their own They must be opened and then placed on a rack in order to be easily filled The opening procedures of both plastic and paper grocery bags are quite time consuming and require wasteful motions In a retail store or convenience store where customer throughput is important, such time consuming operations are objectionable

Consumers have shown a preference for self-standing reclosable plastic containers because of the convenience of filling them, of storing highly fluid liquids in them, and of microwave heating foods directly in the container The art has made attempts at creating such bags, as evidenced by U S Patent No 4,837,849 to Erickson et al , U S Patent No 4,041,851 to Jentsh, U S Patent No 5,375,930 to Tani, U S Patent No 3,249,286 to Palmer, and U S Patent No 4,896,775 to Boeckmann et al Each of these attempts, however, still exhibit several drawbacks For instance, most do not stand easily when empty and are difficult to maintain open when filling and emptying the bags Furthermore, none of the bags fold easily, whereby the bag may be laid flat and then opened quickly to an upright, self-standing position with a minimum of effort Additionally, none of the bags are provided with an accompanying bulk distributing method whereby the bags would be suitable for high volume filling operations

-2- Other needs also exist for containers that are convenient and functional A particular need exists for such a self-standing container that is sealable Such a container could be used to store food items and other perishables and would be much easier to stack and to fill Additionally, if the container were collapsible, the container could also be packaged and distributed efficiently

Nevertheless, barriers exist to the introduction to a self-standing container that is sealable A manner of making a resealable closure of such a container is needed The current manner of closing sealable plastic bags that is used in the art is the bead and groove zipper-type closure device Such a device is not currently in use on self-standing containers because the capablility of economically forming such a closure device on a self standing container does not exist

From the above discussion, it is apparent that a need exists in the art for a self-standing container which is sealable and easily collapsed to occupy a minimum of space, which can be easily opened, and which has the flexibility to meet each of the packaging needs outlined above Additionally, there is a need for such a container which can also be dispensed conveniently in bulk and manufactured using a process that is efficient and inexpensive A method of forming such a container, and corresponding methods of packaging, distributing, and dispensing such containers are also needed

In today's modern packaging environment, for manufacturers to be competitive, packaging products must be relatively inexpensive, which necessitates that the packaging products be produced in high volume and at high speeds and with highly automated systems Accordingly, a need exists in the art for a packaging product which can be easily sealed and unsealed, which can be dispensed economically, and which can be produced efficiently in high volumes and at a high production rate

SUMMARY AND OBJECTS OF THE INVENTION

The present invention seeks to resolve the above and other problems which have been experienced in the art More particularly, the present invention constitutes an advancement in the art by providing a high speed method of manufacture for zipper-type sealable containers

In one embodiment, the method of forming a sealable container comprises providing a container body formed substantially of supple plastic, providing a container lid formed substantially of supple plastic, providing a flexible plastic zipper-type closure device with at least one bend therein, and connecting the plastic zipper-type closure device to at least two sides of the container body and to two corresponding sides of the container lid Providing a flexible plastic zipper-type closure device may comprise positioning a flexible plastic zipper-type closure device in a desired position forming the bend, applying heat to the flexible plastic zipper-type closure device, and allowing the flexible plastic zipper-type closure device to cool and permanently retain the bend therein.

Positioning the flexible plastic zipper-type closure device in a desired position may in one further embodiment comprise placing a strand of raw zipper material within a template. In one embodiment, the template comprises a plurality of blades rotating around a central core, the plurality of blades each having a tip having therein the shape of the bend which is desired to be formed in the flexible plastic zipper-type closure device. An upper mold may also be provided and may be shaped to engage the tip of one of the plurality of templates in mating engagement with the strand of raw zipper material in position at the center thereof. Heat may be applied to the raw zipper material with one of the templates and the upper mold

In an alternative embodiment, the template may be located on an endless conveyor belt The zipper bend forming process may then comprise stringing a strand of raw zipper material on the template with a plurality of rollers and heating the strand of raw zipper material with a heating element located proximal to the template

The container formation method of the present invention may also comprise attaching a strand of raw zipper material in which a bend has been formed to a plastic sheet and trimming the plastic sheet to form a lid In a further step, a section of plastic within a plastic sheet may be thermoformed into the shape of a body of a container The body of the container may then be attached to the lid. Of course, the strand of raw zipper material could be attached to the body first and then connected with the lid

In one embodiment, the body comprises a bottom and at least three sides, and a lip is formed around at least two of the sides at an edge distal to the bottom and at an angle substantially orthogonal to the sides. A strand of raw zipper material in which a bend has been formed may be attached to a second plastic sheet The zipper material on the second plastic sheet may then be joined to the lip. Additionally, a side of the second plastic sheet unoccupied by the zipper material may be attached to one side of the lip

In one embodiment, attaching the zipper material to the lip comprises placing the zipper material and the lip in close proximity to each other and applying heat to one of the zipper material and the lip. An additional step may comprise collapsing the body in order to package the container in a compact area. In so doing, an indentation may be formed in each side and the sides sucked inward. Excess material at each of the corners may also be folded and bent in the direction of the indentation formed in one of the two sides from which the excess material results.

In order to achieve these steps, and form the sealable container, a production system may be provided which comprises a series of subassemblies. These subassemblies may comprise a zipper bending subassembly, a zipper attachment subassembly, a thermoforming subassembly, a lid attachment subassembly, and a trimming and packaging subassembly.

The present invention also provides a method of packaging a flexible, self-standing container. In one embodiment, the method of packaging comprises providing a package for containing a self-standing container, providing a self-standing container formed substantially of a flexible plastic material and capable of self-support in an open configuration, at least partially collapsing the self-standing container; and placing the self-standing container at least partially within the outer container while at least partially collapsed.

A novel sealable, self-standing container is also provided as part of the present invention. In one embodiment, the sealable, self-standing container comprises a body formed substantially of a supple plastic, a lid, and a plastic bead and groove zipper-type closure device, the plastic bead and groove zipper-type closure device connected to at least two sides of the body and to two corresponding sides of the lid. Preferably, the sealable, self-standing container is formed of a supple plastic film such that the self-standing container is capable of being collapsed into a reduced position and of being returned to a self-standing position in which the sealable, self-standing container is self-supporting.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to further clarify the manner in which the above-recited and other advantages and objects of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

-5- Figure la depicts a series of sealable self standing containers in one manner of dispensing the sealable, self-standing containers of the present invention.

Figure lb describes a single sealable, self-standing container in one manner of collapsing the sealable, self-standing container for compact storage.

Figure lc illustrates a method of dispensing the sealable, self-standing containers of Figures la and lb.

Figure Id is a top perspective view depicting the manner of dispensing of Figure lc.

Figure le depicts a second embodiment of a manner of dispensing the sealable, self- standing containers of the present invention.

Figure If depicts a perspective view of the manner of dispensing of Figure le.

Figure lg is a cross-sectional view of the manner of packaging and dispensing of Figure If taken through line A- A of Figure lh.

Figure lh is a top view of the manner of packaging and dispensing of Figures le through lg-

Figure lh is a top view of the manner of dispensing the sealable, self-standing containers of Figures le through lg.

Figure 1 i depicts an alternative embodiment of a sealable, self-standing container of the present invention.

Figure lj depicts a cross sectional view of the sealable, self-standing container of Figure li.

Figure Ik depicts a perspective view of the sealable, self-standing container of Figures li and lj, particularly illustrating the manner of folding of the corners of a lip and zipper thereof.

Figure 2a depicts a lid forming subassembly used in one embodiment of a method of manufacturing the sealable, self-standing containers of the present invention.

Figure 2b depicts a top view of the subassembly of Figure 2a.

Figure 2c depicts a detail view of the subassembly of Figure 2a.

Figure 2d depicts a third portion of the subprocess of Figure 2b.

Figure 2e depicts a zipper attachment subassembly of the method of the present invention and a thermoforming subassembly.

Figure 2f depicts a side view lid attachment subassembly of the method of Figures 2a through 2e.

Figure 2g depicts a side view of a trimming and packaging subassembly of the method of Figures 2a through 2f. Figures 2h through 2j depict one manner of collapsing a container of the present invention.

Figure 3 is a general view of an alternative embodiment of a method of forming sealable, self-standing containers of the present invention.

Figure 4 is a detailed view of a subassembly of the embodiment of Figure 3.

Figures 5a through 5c depict a front view of one manner of operation of a subassembly of the embodiment of Figure 3.

Figure 6 is a perspective view of a subassembly of the embodiment of Figure 3.

Figure 7 is a side perspective view of an alternative embodiment of the subassembly of Figure 6.

Figure 8is a top perspective view of a further subassembly of the embodiment of Figure 3.

Figures 9a through 9c depict a side view of a further subassembly of the embodiment of Figure 3.

Figures 10a through lOd depict the operation of a subassembly of the embodiment of Figure 3.

DETAILED DESCRIPTION OF THE INVENTION

Shown in Figure la is a side view of one embodiment of a sealable, self-standing container 10 and a method of packaging and dispensing sealable, self-standing containers 10 of the present invention. A single sealable, self-standing container 10 is shown in Figure la and is presented in an unfolded configuration. Contained within the sealable, self-standing container 10 are a pair of folded or collapsed sealable, self-standing containers 12, 14 similar to the sealable, self-standing container 10, but somewhat smaller in size. The sealable, self-standing containers 10, 12, 14, are preferably formed of plastic. More preferably, the plastic is a highly flexible and supple plastic film. Examples of suitable plastic films for use in forming the sealable, self-standing containers 10, 12, 14 of the present invention include polyolefins, an example of which is polyethylene. One supple plastic film commercially available comprises linear, low density polyethylene available from Nexus Plastics of Hawthorne, New Jersey.

The depicted sealable, self-standing containers 10, 12, 14 each include a body 16 and a lid 18. Preferably, the lid 18 is attached to the body 16 on one side, as best seen in Figure Ik, although the lid 18 could also be separable from the body 16. The body 16 is preferably formed with a bottom 17 and four sides 22. Of course, the body 16 could have fewer or greater than four sides. Each of the four sides 22 are shown attached to the bottom 22 and are continuously interconnected

-7- to form the sides of a box. The body 16 is shown to be self- standing, due to its configuration, even though formed of a highly supple material.

An upper zipper portion 20a is shown traversing around the three unattached sides of the lid 18. A lip portion 26 extends outward perpendicular to the sides 22 of the body 16 and is used for connecting a bottom zipper portion 20b to the body 16. The lip portion 26 is best seen from atop view in Figure Id. The lip portion 26 may be integral to the body 16, or may be attached as an insert to the body 16. The bottom zipper portion 20b is attached proximal to the outer edge of lip portion 26 on three sides of the lip portion 26. Preferably, the zipper portions 20a, 20b together comprise a plastic bead and groove type zipper.

The plastic bead and groove type zipper is preferably formed of a flexible material such as plastic. As used herein, the term "bead and groove-type zipper" comprises any zipper-type device in which a male portion is matingly received by a female portion. In keeping with this definition, the male portion could be a bead, but the bead is not restricted to a rounded shape. One example of a bead and groove-type zipper suitable for use with the present invention is the String Fastener zipper available from Com-Pac, International of Carbondale, Illinois.

The use of the lip 26 allows the bead and groove of the bead and groove-type zipper to be oriented facing one another in a vertical direction, which is preferred for ease of opening and closing the lid and sealing the zipper. The bead may correspond to the upper portion 20a, in which case the groove corresponds to the lower portion 20b, or vice verse. The bead and groove-type zipper 20 is shown provided with two bends (shown at 20c in Figure 1 d) therein which allow the zipper 20 to traverse a plurality of sides 22 of the container. In one embodiment, the zipper 20 is provided with a permanent or semi-permanent memory of these bends 20c for easier manufacturing and for retaining the shape of the container 10. Manners of providing these bends 20c or similar bends and attributing a memory within the bead and groove-type zipper of these bends are disclosed below.

Referring now to Figure lb, seen therein is a sealable, self-standing container 10 of the present invention shown in a collapsed position for compact shipping, storage, and dispensing. In the sides 22 are shown folds 24 which may be temporary or may be permanently or semipermanently scored, thermal formed, or otherwise formed within the sides 22. In collapsing the sides 22, an inward force may be asserted against each side at once, while the lid 18 and bottom 17 are compressed. Overlapping corner portions 25 result, and are collapsed together with one of the two sides 22 which form the respective corner portions 25. Referring now to Figure 1 c, shown therein is a manner of packaging and dispensing the sealable, self-standing containers 10 of the present invention. As seen therein, once the sealable, self-standing containers 12, 14 have been formed, sealed, and collapsed as in Figure lb, they may then be inserted one atop the other within the sealable, self-standing container 10. Once inserted, the lid 18 of the sealable, self-standing container 10 may be closed and sealed. The lid 18 may be attached to the body 16 prior to insertion of containers 12, 14, or may be attached after the sealable, self-standing containers 12, 14 have been inserted therein. The sealable, self-standing containers 12, 14 may be of a common size or may be of different sizes. Of course, more or less than two sealable self-standing 12, 14 may be packaged within the outer sealable, self-standing container 10.

Figure Id shows a top perspective view of the packaging system of Figure lc. As seen in Figure Id, the inner sealable, self-standing containers 12, 14 are preferably formed, and collapsed before insertion into an opening 19 of the outer sealable, self-standing container 10.

Referring now to Figure 1 e, shown therein is an alternative embodiment of a system for packaging and dispensing the sealable, self-standing containers, in which the sealable, self-standing containers 10 of the present invention are packaged in a nested manner.

Shown in Figure le is an outer sealable, self-standing container 30 and an intermediate sealable, self-standing container 34 nested within the outer sealable, self-standing container 30. An inner sealable, self-standing container 32 is shown nested within the intermediate sealable, self- standing container 34. Thus, the sealable, self-standing containers 30, 32, 34 may be formed, sealed, packaged and dispensed in substantially the same manner described above for Figure lc, with the exception that the intermediate and inner sealable, self-standing containers 32, 34 in this embodiment need not be folded or collapsed prior to insertion within the outer sealable, self- standing container 30. Of course, any of the sealable, self-standing containers 30, 32, 34 could still be partially or fully collapsed in order to save space.

Figure If is a top perspective view of the packaging and dispensing system of Figure le. Figure lg is a cross-sectional view taken around line A-A of Figure lh. Figure lh is a top view of the system of Figures 1 e and 1 f. As seen in Figures 1 e through 1 h, the sealable, self-standing containers 30, 34, 32 are of progressively smaller sizes to facilitate the nested manner of packaging and dispensing. The sealable, self-standing containers may be formed of a transparent material, and a label 35 or other advertising materials may be placed within the outer sealable, self-standing container 30.

-9- Referring now to Figure li, shown therein is an alternative embodiment of the sealable, self- standing containers of the present invention. Thus, as seen therein, a sealable, self-standing container 50 may comprise a body 52, having four sides 51, a bottom 53, and a lid 54. The lid 54 is shown provided with a lip portion 60 that folds down as seen in the cross-sectional view of Figure lj taken at line A-A of Figure li. By folding the lip portion 60 down, the zipper 56 can, in one embodiment, be attached to the container 50 without first providing the zipper 56 with- the bends and memory of the bends needed to occupy the various different sides of the container 50, as discussed above.

Located on the outer edges of the lip portion 60 is a lower zipper portion 56b. Around the outer edges of the lid 54 is an upper zipper portion 56a. The upper and lower zipper portions 56a, 56b preferably traverse around three sides of the lip portion 60 and lid 56. The remaining side of the lid 54 and the body 52 are preferably attached together.

Referring now to Figure lj, shown therein is a cross-sectional depiction of the sealable, self- standing container 50 of Figure li. As seen therein, the upper and lower zipper portions 56a, 56b traverse around three sides of the body 52a at a horizontal orientation rather than the vertical orientation of Figures la through lh. Due to the horizontal orientation, the zipper 56a, 56b need not be heated and can be merely flexed around the body 52a when attaching the zipper 56a, 56b to the lip portion 60 and the lid 58.

Referring now to Figure Ik, shown therein is a top perspective view of the sealable, self- standing container 50 of Figures li and lj. Figure Ik shows a manner of rotating the zipper portions 56a, 56b at the far corners 64. Thus, while at the distal corners 64, the zipper portions 56a, 56b remain in the horizontal orientation, and they transition into the vertical orientation of Figures la through lh as the zipper portions near the proximal corners 62.

A further manner of forming the sealable, self-standing containers 10 is described in U.S. Patent Number 5,735,423, which is hereby incorporated by reference into this document.

Referring now to Figures 2a through 2g, shown therein is an apparatus, system, and method for forming the self-standing containers of Figures la through Ik. Referring first to Figure 2a, shown therein is a portion of a system 200 for manufacturing the sealable, self-standing containers 10, 30, 50 of the present invention. The system 200 comprises a zipper formation subsystem 205 including an endless conveyor belt 210 having therein embedded zipper holders 201. The zipper formation substation 205 is used to impart bends to the zippers and to impart a memory of those bends to the zippers. By providing zippers with a memory of the bends therein, the zippers can be

-10- placed on containers having multiple planes and can be more easily connected between the different planes of those containers, as will be discussed

The endless conveyor belt 210 and the embedded zipper holders 201 are also seen in Figure 2b, which is a top view of the subsystem 205 As seen therein, raw zipper material 208 is held within spools 206 which provide zipper material 208 that is passed through ports 207 into channels 202 within the endless conveyer belt 210

Figure 2c is a detail view of detail A showing a cross-sectional view of the zipper material 208 placed within the channels 202 In the depicted embodiment, the channels 202 are fixed in place on the endless conveyer belt 210, and the zipper holders 201 move with the endless conveyor belt 210 The endless conveyor belt 210 is stopped for the zipper formation process of the subsystem 205 to be conducted at a position wherein the channels 202 and zipper holders 201 are aligned

A series of zipper placement devices, in the preferred embodiment comprising rollers 204, carry the zipper material 208 through the zipper loading ports 207 and into the channel 202 and help to route the zipper material 208 through the channel 202 and into a contiguous relationship with the zipper holder 201 Once the zipper material 208 is carried all the way through the channel 202, heat is applied to at least at the corners 207 of the channel to mold the zipper into the horseshoe shape of the channel 202 as shown in Figure 2b Thereafter, the endless conveyor belt 210 carries the series of horseshoe-shaped raw zipper segments 215 into the next portion of the system 200, as shown in Figure 2d The zipper material 208 may be heated to a suitable degree prior to guiding it through the channel 202 to impart flexibility thereto

The channels 202 may extend continuously through channel bridge sections 209, or the bridge sections 209 may be open Heat sources 203 such as heating coils or heating elements provide the heat for heating at least the comers of the raw zipper material 208 to relax or otherwise encourage permanency of the bending operation

Preferably, the rollers 204 are disposed above and below the endless conveyor belt 210 in the manner shown in Figure 2c The channel 202 may be formed by metal channel guides 21 1 Alternatively, the channel guides 21 1 may be made of the same material as the endless belt 210 or of some other suitable material in which the heating elements 203 may be embedded

Once the zipper material 208 is loaded fully within the channel 202, the conveyor 210 is advanced, carrying the zipper material 208 within the zipper holders 201 During or after advancement of the endless conveyor belt 210, the zipper material 208 is trimmed to remove excess

-1 1- zipper material 208 from the channel bridge segments 209 The term "zipper material" as used herein is intended to mean unshaped, uncut, and unattached threads of sealed together upper and lower zipper portions such as the zipper portions 20a, 20b of Figure la.

Shown in Figure 2c is a portion of the channel 202 having therein the zipper material 208. The rollers 204 shown pressing upon the zipper material 208 from above and beneath the zipper raw material 208 are preferably powered, e.g., by a motor, to carry the zipper material 208 throughout the zipper bending channel 202, while the zipper bending channel 202 guides the raw zipper material 208 into a conforming, contiguous relationship with the zipper guides 201.

Referring now to Figure 2d, shown therein is a portion of the endless conveyor belt 210 of Figure 2b, seen transitioning into a zipper attachment subprocess 220 in which the now properly shaped and trimmed zipper sections 215 held within the zipper holders 201 are attached to a sheet of plastic material 214 for forming a lid such as lids 18, 54 of Figures la-Ik To form the lid 18, 54, the sheet of raw plastic material 214 is guided into a position just above the endless conveyer belt 210 Within the subprocess 220 is shown heat source plates 222 which are brought to bear against the plastic material 214 and the zipper segments 215, pressing the plastic material 204 and the zipper segments 215 together between the heat source plates 222 and the resistence plates 224 Heat is concurrently applied through the heating plates 222 to adhere the zipper sections 208 to the raw material 214

At the conclusion of the zipper attachment subprocess 220 of Figures 2d and 2e, the plastic material 214 to which the zipper segments 215 are connected carries the zipper segments away from the zipper holders 201 The plastic material 214 and zipper segments are thus made suitable to function as container tops 18 and attached zipper portions 18 The zipper holders 201 are subsequently conveyed with the endless conveyor belt 210 back to the beginning of the high speed zipper bending subprocess 205

Also shown in Figure 2d is a thermoforming subsystem 230 including a lower conveyor system comprising a continuous sheet of plastic 212 dispensed from a spool 213 Above the continuous sheet of plastic 212 is a mold 232, which may be a male mold or a female mold and is preferably box-shaped Using a conventional thermoforming or vacuum forming process, the sheet of plastic 212 is formed into a body 16 with four sides 22, a bottom 17, and an opening 19, as seen in one embodiment in Figures 1 a through 1 k Of course, one skilled in the art will recognize that the body 16 may be of other than the conventional box shape described herein For instance, a rectangular shape may also be used to package food and other irregularly shaped items A

-12- triangular shape might be used to package cheese, and a round shape might be used to package cakes, etc.

Shown in Figures 2d through 2f is a base-to-lid attachment subsystem 240. The subsystem 240 connects the portion of the plastic sheet 214 that is to be the container lid 18, with the zipper segments 215 attached thereon, to the container body 16 formed by the subsystem 230 of Figure 2d. Initially within the subsystem 240, as shown by Figure 2d, the zipper segments 215 are separated from the zipper holders 201 and are conveyed by the sheet of raw plastic material 214 to which they are attached into the subsystem 240, as shown in Figure 2c. The zipper holders 201 are subsequently conveyed back to the beginning of the high speed zipper bending system 205 of Figure 2a.

Subsequently, as seen in Figures 2e and 2f, the container lid 18 and the container base 16 are aligned into an adjoining relationship. Once aligned, a heat source 242 is applied to the bottom of a lip, such as the lip 26 of Figure la, and presses the lip 26 and contiguous container lid 18 between the resistance plate 244, concurrently applying heat to the lip 26 (or optionally to the container lid 18) to attach the lip 26 to the container lid 18. In so doing, one side of the lip 26 may be attached to one side of the lid 18, and three sides of the lip 26 attached to the bottom portion 20b of the zipper segment 215. The heat source 244 preferably comprises a square aperture for fitting the body 16 therein. The lip 26 may be attached to the body 16 prior to attaching the lip 26 to the lid 18 and to the bottom portion 20b of the zipper segment 215.

Finally, as depicted in Figure 2g, the lid 18 and base 216 are trimmed and the completed sealable, self-standing container 250 is exited from the system 200.

Shown in Figures 2h through 2j is embodiment of a process of folding or collapsing the sealable, self-standing containers 10 of Figures l a and lb for compact packaging and dispensing. The folding process of figures 2h-2j may be conducted after the formation process conducted by the system 200 of Figures la-lg. Shown in Figure 2h is a collapsing system 260 comprising a cavity 262 and guiding plates 264. The body 16 of the sealable, self-standing container 10 is placed within the cavity 262, and a vacuum is applied to the sealable, self-standing container 10. Concurrently, a series of horizontal guiding plates 264 are pressed concurrently into the centers of each of the four sides 22 of the sealable, self-standing container 10.

The guiding plates 264 are pressed inward, creating an inward fold on each of the four sides 22 while the vacuum is applied, as shown in Figure 2i. The continued vacuum causes the body 16 to be drawn up towards the lid 18 as shown in Figure 2j, creating the collapsed sealable, self-

-13- standing container 18 of Figure lb. The sealable, self-standing container 18 may be fully collapsed or may be partially collapsed as shown in Figure lb.

Referring now to Figure 3, shown therein is an alternate embodiment of a system and method for manufacturing the sealable, self-standing containers of Figures la through Ik. The system and method are embodied as a manufacturing system 300. The manufacturing system 300 is shown comprised of a zipper forming subassembly 310, a zipper attachment subassembly 322, a thermoforming subassembly 324, a lid attachment subassembly 326, and a trimming and packaging subassembly 350.

The manufacturing system 300 is depicted in Figure 3 as comprising a first plastic sheet 302 from which the lids 18 of the sealable, self-standing containers 10 are formed. A heating plate 304 and a resistence plate 305 are also shown, as are a rotating zipper mold 312 and zipper portions 308 held by clips 327 to an endless conveyer belt 329. Figures 4 through 8 show subassemblies of the system 300, and Figure 9 shows an alternate embodiment of the subassembly of Figure 8.

Referring now to Figure 4, shown therein is basic embodiment of a zipper bending subassembly 310. The purpose of the zipper bending subassembly 310 is to permanently or semipermanently form a bend in a plastic zipper. That is, to form a plastic zipper having a "memory" of a bend therein. As defined herein, the term bend, when used to describe a plastic zipper is intended to mean a plastic zipper in which is formed a radius or which is substantially nonlinear.

Within the zipper bending subassembly 310 is a rotating zipper mold 312 comprised of a rotating core 313 and with a plurality of blades 312a, 312b emanating outward therefrom. At the top of each blade 312a, 312b is a shaped template 321. A single blade 312a may be provided, or multiple blades 312a, 312b, etc. may be provided. The top of the blades 312a, 312b are depicted as being substantially square with rounded corners and a channel 309 to receive a strand of raw zipper material 307 and form the raw zipper material 307 into a suitable shape as required in the formation of the containers of Figures la through Ik.

A line of raw zipper material 307 is shown being threaded through a channel 309 in the rotating zipper mold 312. An upper zipper mold 31 1 is shown configured for mating conformity with the curved template 321 at the top of the blades 312a, 312b.

Figures 5a through 5b show the zipper bending subassembly 310 in greater detail. Seen in Figure 5a is the top mold portion 31 1, the curved template 321, guiding rollers 319 and retractable guiding elements 325. The strand of raw zipper material 307 is carried by the rollers 319 across

-14- the first guiding element 325, across the bottom mold portion 321, through the channel 309 and across the second guiding element 325 at the far side A blade (not depicted) is used to cut the raw zipper material 307 at a point just prior to the first of the zipper guides 325 The blade may be heated for cleaner cutting, of the raw zipper material 307.

As seen in Figure 5b, the upper mold portion 31 1 is thereafter pressed down onto the curved template 321 while the guiding elements 325 reciprocatingly also retract downward Heat is then applied through either the upper zipper mold 311 or the lower rotating zipper mold 312

Subsequently, as seen in Figure 5c, the upper zipper mold 311 is lifted upward, while the guiding elements 325 correspondingly are also correspondingly raised upward The upper mold 311 is fully removed and the raw zipper material 307 is then allowed to cool into a formed zipper portion 308 The formed zipper portion 308 thereafter retains a desired shape conforming substantially to the shape of the top of the blades 312a, 312b and the upper zipper mold 31 1 In the depicted embodiment, the desired shape is a substantially horseshoe shape The rotating core 313 is then rotated to perform the above-described operation on the next blade 312b

As shown in Figure 6, while the blades 312 rotate, the shaped zipper portion 308 is captured by clips 327 on the endless belt 329 The capturing by the clips 327 can be a manual or automatic operation In the depicted embodiment, automated pistons 333 push the blades from the channel 309 and into the receiving clips 327 The clips 327 are shown as one embodiment of a manner of fastening the zipper portion 308 to the conveyer belt 329 Of course, other suitable fastening means could also be used For instance, templates could be used such as the guides 201 described above for Figure 2b Recesses located within the conveyer belt 329 and shaped to the zipper portions 308 could also be used

In one embodiment, the surface of the template 321 of the rotating mold 312 is provided with a recess 331 as shown in Figure 7 to facilitate gripping and placement of the zipper 308 onto the endless conveyor belt 317 The recess 331 can be as deep as needed, to expose the zipper portion to proper gripping by clips 327 or other handling equipment. Thus, in one embodiment, the clips 327 capture the zipper portion 308 from within the channel 309 by accessing the zipper portion 308 through the recess 331 as both the blades 212 and the conveyer belt 329 rotate and the clips 327 come into contact with the zipper portion 308

The shaped zipper portions 308, once transferred onto the conveyor belt 317, are conveyed between the heating element 304 and the resistence plate 305 of Figures 3, 8, and 9a through 9b.

-15- As seen in Figures 8 and 9a, a portion of the sheet of plastic 302 is passed just over the top of the zipper portions 308. The resistance plate 304 may be mounted to a press 328 for lowering it into contact with the plastic sheet 302 as shown in Figures 9a and 9b.

As seen in Figure 9b, heat is preferably applied by the heating plate 304 while the heating plate 304 and resistance plate 305 are pressed against each other with the sheet of plastic material 302 and the zipper portion 308 in the center thereof.

As seen in Figure 9c, the heating element 304 is removed, and the zipper portion 308 is allowed to cool and attach to the sheet of plastic 302. Thereafter, the portion of the sheet of plastic material 302 to which the zipper portion 308 is attached is transferred to the lid attachment subassembly 326 of Figure 3.

Figure 8 is shown with the sheet of plastic 302 and the endless conveyor belt 329 oriented in different directions from the embodiment of Figure 3. It should be readily apparent to one skilled in the relevant art from the depicted embodiments that many different configurations of the basic operations given here by way of example could be employed. Figure 8 shows one manner of exiting the plastic material 302 with the formed zipper portions 308 from the endless conveyer belt 329. Within Figure 8, the endless conveyer belt 329 revolves around a roller 331 and returns to its initial starting place, while the plastic sheet 329 goes on toward the plastic sealer 306 with the zipper portion 308 permanently attached thereto.

While the zipper portions 308 are being formed and attached to the plastic sheet 302, the thermoforming substation 324 is concurrently in operation. As seen in Figures 3 and 10a, a sheet of plastic sheet 320 is carried into the thermal former 314 from a spool 328. Thereafter, a thermoforming process is then conducted in a manner well known in the art to form a body 16 within the plastic sheet 12. The thermoforming process may be conducted in substantially the same manner as has been discussed above for Figure 2d or may be any conducted using any other manner of thermoforming known in the art.

After the body portion 16 is thermoformed, it is preferably not trimmed from the plastic sheet 320, but is carried by the plastic sheet into the lid attachment subassembly 326. Around the walls 22 and bottom 17 of the body 16 remains a portion of the plastic sheet 320 which is extends outward substantially orthogonal to the walls 22 of the body portion 16. This portion of the plastic sheet 320 will form the lip 28 of Figure 1 after the body 16 is trimmed and removed from the plastic sheet 320.

•16- Once the zipper portion 308 is attached to the plastic sheet 302 and the body 16 is formed complete with the lip 26, the lid 18 and zipper portion 308 is attached to the body with the lid attachment subassembly 226. One embodiment of a lid attachment subassembly 226 for sealing lid portions 18 within the plastic sheet 302 to body portions 16 within the plastic sheet 320 is shown in Figures 10a to lOd

As seen in Figure 10a, a heating plate 318 is provided with a heating element and a hollow center portion 316 suitable for receiving the thermoformed body portion 16 therein. A resistence plate 306 is also shown and is adapted to provide a resistence against the heating element 318 with the aligned lid portion 18 of the plastic sheet 302 and thermoformed body 16 of the plastic sheet 320 pressed therebetween

One or both of the resistance plate 306 and the heating plate 318 may be mounted on a press for moving the resistance plate 306 into pressing engagement with the heating plate 318 In Figures 10a through lOd, the heating plate 3 18 is mounted to a press 332 and the resistance plate 306 is mounted to a press 334

Figure 10b shows the press 332 carrying the heating plate upward and the press 334 carrying the resistance plate 306 downward The heating plate 318 and resistance plate 306 are thus moved into pressing engagement with the plastic sheets 302 and 320 pressed together therebetween. The lip 28 of the thermoformed body 16 on the plastic sheet 320 is aligned with the zipper 308 on the plastic sheet 302 The heating plate 318 heats and seals the bottom of the zipper 308 to the lip 26 of the body 16 A side of the lid 18 which is unoccupied by the zipper 308 is also sealed to one side of the lip 26 to attach the lid 18 to the body 16 The heating plate 318 and resistance element 306 are then retracted as seen in Figure lOd, and the thusly formed container 10 is allowed to cool

Returning to Figure 3, the container 10 having the base portion 16 with the lid 18 now attached thereto emerges from the lid attachment subsystem 326 into the trimming and packaging subassembly 350, where the lid 18 and plastic sheet 320, to which the base 316 is still attached, are trimmed into the appropriate shapes seen in Figures 1 a and 1 b

Within the trimming and packaging subassembly 350, the containers 10 may be collapsed as described above in relation to Figures 2h through 2j and may be packaged individually or together with other thusly formed containers 10 The various manners of packaging described above for Figures la through lh may be employed

■17- Referring to the packaging embodiments of Figures la and If, the body portions 16 of the outer containers 10, 30 can first be formed and the inner containers then placed therein The sealing procedure of the lid attachment subassembly 326 can then be conducted on the outer containers 10, 30 to attach the lids thereto with the inner containers already placed therein

Claims

CLAIMS:

1. A method of forming a sealable container, comprising: a. providing a container body formed substantially of supple plastic; b. providing a container lid formed substantially of supple plastic; c. providing a flexible plastic zipper-type closure device with at least one bend therein; and d. connecting the plastic zipper-type closure device to the container body and to the container lid.

2. The method of claim l,wherein connecting the plastic zipper-type closure device to the container body and to the container lid comprises connecting the plastic zipper-type closure device to at least two sides of the container body and to at least two corresponding sides of the container lid.

3. The method of claim 1, further comprising permanently connecting the container lid to the container body.

4. The method of claim 1, wherein providing a flexible plastic zipper-type closure device further comprises; positioning the flexible plastic zipper-type closure device in a desired position forming the bend; applying heat to the flexible plastic zipper-type closure device; and allowing the flexible plastic zipper-type closure device to cool and permanently retain the bend therein.

5. The method of claim 4, wherein positioning the flexible plastic zipper-type closure device in a desired position comprises placing a strand of raw zipper material within a template.

6. The method of claim 5, wherein the template comprises a plurality of templates rotating around a central core, the plurality of templates each provided with a tip having therein the shape of the bend which is desired to be formed in the flexible plastic zipper-type closure device.

7. The method of claim 6, further comprising an upper mold shaped to engage the tip of one of the plurality of templates in mating engagement with the strand of raw zipper material in position at the center thereof.

8. The method of claim 6, further comprising applying heat to the raw zipper material with one of the templates and the upper mold.

9. The method of claim 5, wherein the template is located on an endless conveyor belt.

-19- 10 The method of claim 9, further comprising stringing a strand of raw zipper material on the template with a plurality of rollers

11 The method of claim 9, further comprising heating the strand of raw zipper material with a heating element located proximal to the template

12 The method of claim 1, further comprising attaching a strand of raw zipper material in which said bend has been formed to a plastic sheet and trimming the plastic sheet to form a lid

13 The method of claim 1, further comprising thermoforming a section of plastic within a plastic sheet into the shape of the container body

14 The method of claim 13, wherein the body comprises a bottom and at least three sides, and comprising forming a lip around at least two of the sides at and edge distal to the bottom and at an angle substantially orthogonal to the sides

15 The method of claim 14, further comprising attaching a strand of raw zipper material in which a bend has been formed to a second plastic sheet and attaching the zipper material on the second plastic sheet to the lip

16 The method of claim 15, further comprising attaching a side of the second plastic sheet unoccupied by the zipper material to one side of the lip

17 The method of claim 15, wherein attaching the zipper material to the lip comprises placing the zipper material and the lip in close proximity to each other and applying heat to one of the zipper material and the lip

18 The method of claim 1, further comprising collapsing the body in order to package the container in a compact area

19 A method of packaging a flexible, self-standing container, comprising a providing a package, b providing a self-standing container formed substantially of a flexible plastic material and capable of self-support in an open configuration, c At least partially collapsing the self-standing container, and d placing the self-standing container at least partially within the outer container while at least partially collapsed

20 A sealable, self-standing container, comprising a a body formed substantially of a supple plastic, b a lid, and

-20- c. a plastic bead and groove zipper-type closure device, the plastic bead and groove zipper-type closure device connected to at least two sides of the body and to two corresponding sides of the lid, the sealable, self-standing container capable of being collapsed into a reduced position and of being returned to a self-standing position in which the sealable, self-standing container is self-supporting.

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