WO1998046497A1

WO1998046497A1 - Thermally insulated foam in bag packaging cushion

Info

Publication number: WO1998046497A1
Application number: PCT/US1998/007449
Authority: WO
Inventors: Laurence Burst Sperry; Anthony Orkin Davlin; George Teofilius Bertram; Charles P. Kannankeril
Original assignee: Sealed Air Corporation
Priority date: 1997-04-14
Filing date: 1998-04-13
Publication date: 1998-10-22
Also published as: AU6970398A

Abstract

A foam in bag packaging cushion (20) containing foam precursors (21) in which the bag is formed of a material that has insulates the outer surface of the bag against conductive heat transfer from heated contents inside the bag.

Description

THERMALLY INSULATED FOAM IN BAG PACKAGING CUSHION

Field of the Invention

The present invention relates to foam-in-place packaging systems and in particular relates to the manufacture, structure, and use of bag cushion precursors that carry foamable compositions, and that are well-suited for manual -handling.

Background of the Invention

The present invention relates generally to foam-in- place packaging. Foam-in-place packaging has been well known and widely used as a protective packaging method for a number of years. The underlying technology is based upon the reaction between two (usually liquid) chemicals that form a solid polymer while at the same time generating a gaseous by-product. In particular, when isocyanate compounds react with polyols and water, the reaction produces both a urethane polymer ( "polyurethane" ) and carbon dioxide. Under proper conditions, the carbon dioxide generated by the reaction will bubble and disperse through the polymer as it hardens to thus form an expanded polymer foam that can be used as a protective material for packaging fragile objects. The process by which the liquid precursors mix as liquids and then expand as not-yet-hardened foam typically takes about 20 seconds, thus making feasible its manipulation and use for packaging purposes. In a first generation of foam-in-place packaging, objects to be protected were placed into containers (e.g. corrugated boxes) , and wrapped or draped with a protective material such as a plastic sheet. Thereafter, the polyol and isocyanate were pumped from separate supplies, mixed, and then injected from a gun-like dispenser into the container. If the amount of injected mixture was appropriate, the resulting foam would essentially fill the interior of the container while surrounding the object to provide a custom package. Such relatively straight forward injection practices are still useful in many applications, and an updated injection device is disclosed, for example, in copending and commonly assigned application Serial No. 08/361,322 filed December 21, 1994 for " Hand Held Dispenser for Foamable Composi tions and Dispensing System . "

In a next generation of foam-in-place packaging, devices have been developed which concurrently produce plastic bags and fill them with the foamable mixture of polymer precursors . The bags include a vent to permit the carbon dioxide to escape. A packaging operator can simply drop one or more newly made bags into a container carrying an object to be packaged, and then close the container. The foam in the bag continues to generate and expand until it likewise fills the interior of the container while forming a custom-shaped cushion around the object packaged therein. Such bag making systems provide the advantage of injecting the foam into a bag that is immediately closed, rather than requiring the operator to manually dispense the foam. As is known to those familiar with such foamable chemicals, they tend to be extremely messy and, if not controlled properly, can cause problems which slow or stop the entire packaging process until the unwanted foam residue can be cleaned up. In more serious circumstances, the foam can even cause its handling machinery to break down leading to further additional delays.

Examples of foam-in-place devices are described in a number of patents and copending applications that are commonly assigned with the present invention. These include inter alia, U.S. Patent Nos . 4,800,708; 4,854,109, 4,938,007; 5,027,583; 5,139,151 and 5,376,219 and pending applications Serial Nos. 08/121,751, filed September 15, 1993 and 08/514,010 filed August 11, 1995.

The packaging requirements of various users can, however, differ widely. Thus, any particular given foam-in- place system may not be appropriate or economically viable for every potential user. For example, users who repetitively use foam cushions on a large volume basis are probably most appropriately served by one of the more sophisticated devices such as those described in U.S. Patents Nos. 5,376,219 or 4,800,708. For less frequent users, the smaller and more compact devices such as that illustrated in pending applications Serial Nos. 08/121,751 and 08/514,010 may be appropriate, and as mentioned above, some users still prefer the simplest technique of using an injection system with a gun type device that dispenses the foam.

Nevertheless, the market lacked any foam-in-place packaging system for the less frequent user who would otherwise like to take advantage of foam-in-place packaging, but has neither the desire nor the facilities to incorporate any one of the previous mentioned foam-in-bag systems.

Accordingly, it has been considered desirable to manufacture a bag in which the foam precursors are separately maintained during storage so that in use, the packaging operator can simply take one of the bags, mix the ingredients by hand (i.e. handle the bag's exterior while mixing the precursors inside) , and then place the expanding bag and foam into a package for purposes identical to those just described.

To date, however, attempts at doing so have been generally unsuccessful for reasons that are best illustrated by U.S. Patents Nos. 3,419,134 to Fitts, and 4,232,788 to Roth.

Fitts ' 134 discloses several variations of a foamable package and a method for forming cellular foam in which the foam precursors are placed in two separate smaller bags inside a larger bag. According to Fitts, there are rupturable "partitions" or "walls" between the bags, so that when the operator physically breaks the partitions, the chemicals will mix and form foam. The Roth '788 disclosure is essentially the same from a conceptual standpoint. Each of these suffer from some significant disadvantages, however, and essentially neither has appeared on the marketplace in any significant presence.

There are several reasons for this failure. First, in order to produce foam, the two foam precursors must mix as thoroughly and completely as possible. Indeed, the successful thorough mixture of the foamable precursors is a fundamental requirement for all foam-in-place systems. Stated differently, if the foam precursors fail to mix successfully, either foam will not be produced, or the foam that is produced will be structurally inappropriate.

More recently, however, a more acceptable foam-in-bag cushion precursor has been developed, and the same is described in copending application Serial No. 08/626,981 filed April 3, 1996 for "Foam-in-Bag Packaging System," which is commonly assigned with the present invention and which is incorporated entirely herein by reference. As set forth therein, an appropriate combination of materials can provide a useful cushion precursor that carries the foamable compositions in separate portions until intentionally mixed by the end user.

The nature of the cushion precursors described in ' 981 application are such that they encourage--and favorably so-- the end user to manually manipulate a cushion precursor to thereby break the intended interior seals and thus initiate the foam-forming process. The reaction, however, often generates enough heat (depending upon ambient circumstances) to cause the foam (and the bag's surface) to reach or exceed the pain threshold for human touch, while under typical circumstance is considered to be about 113°F (45°C) . Accordingly, some users may be discouraged from taking advantage of the bag' s capability because of the unpleasant sensation of heat.

As a separate issue, some items that require shock- resistant packaging are also sensitive to higher temperatures. In this regard, the isocyanate component - polyol component reaction generally raises the temperature of the core of the foam- -albeit temporarily- -to about 200- 210 °F, and thus raises the temperature at the edge of the foam to about 160°F. Because the purpose of foam-in-place packaging is to have the foam surround the item to be protected before the foam hardens, foam-in-place packaging becomes less desirable for items that could or would be harmed at temperatures noticeably warmer than ambient and including the 160 -210 °F temperatures reached by the foam. Furthermore, the heated water vapor produced by the foam- generating reaction is an efficient medium for heat transfer, thus adding to the overall heat problem in certain circumstances .

Therefore, the need exists for a foam-in-bag cushion precursor which transfers less heat to the sensation of touch based on the heat generated by the foam forming composition, and which transfers less of the heat of reaction from the foamable composition to a heat-sensitive item being packaged.

Object and Summary of the Invention Therefore, it is an object of the invention to provide a foam-in-bag cushion that can be manually handled as the foamable composition generates foam and heat without significant discomfort to the user.

It is a further object of the invention to provide a foam-in-bag cushion that protects temperature-sensitive items from the heat generated by the foam-forming reaction.

The invention meets these and other objects with a foam-in-bag packaging cushion containing foam precursors in which the bag is formed of a material that has insulating characteristics that sufficiently moderate the transfer of the heat generated by the foam precursors to keep the temperature on the outer surface of the bag below the expected pain threshold for human touch as the foam precursors react to foam. In another aspect, the invention is a foam-in-bag cushion that insulates the outer surface of the bag against conductive heat transfer from the contents inside the bag. The foregoing and other objects, advantages and features of the invention, and the manner in which the same are accomplished, will be more readily apparent upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings, which illustrate preferred and exemplary embodiments, and wherein:

Brief Description of the Drawings

Figure 1 is a perspective view of a thermally insulated bag according to the present invention;

Figure 2 is a cross-sectional view of the bag material taken along lines 2-2 of Figure 1 ;

Figure 3 is a perspective view of another embodiment of the invention that incorporates a gas permeable material as a ventilation means for the escaping gases;

Figure 4 is a perspective view of another embodiment of the cushion with three sealed edges and one folded edge;

Figure 5 is a perspective view of another embodiment of the cushion formed from tube stock with two folded edges and two sealed edges;

Figure 6 is a partial perspective, partial cross- sectional view of one of the insulating materials preferred for the invention;

Figure 7 is a partial perspective, partial cross- sectional view of a second insulating material used in cushions according to the present invention; Figure 8 is a perspective view of a hand-mixable bag according to the present invention;

Figure 9 is a cross-sectional view taken along lines 9- 9 of Figure 8 ; and

Figure 10 is a cross-sectional view taken along lines 10-10 of Figure 9. Detailed Description of the Preferred Embodiments

The present invention is a foam-in-bag packaging cushion such as is broadly designated at 20 in Figure 1. The bag 20 is formed of a material that insulates the outer surface of the bag against conductive heat transfer from heated contents inside the bag; i.e., as the foam precursors 21 form foam.

Stated differently, the invention is a foam-in-bag cushion that is particularly suitable for manual contact and handling during the generation of the foam cushioning materials from the foam precursors 21. The foam-in-bag cushion 20 comprises two overlying sheets 22 and 23, four closed edges 24, 25, 26, and 27 that together with the sheets 22 and 23 define a sealed bag, and the foamable composition 21 in the sealed bag.

It will be understood that Figures 1, 3, 4 and 5 illustrate the bags as ideally-shaped pillows in order to facilitate an understanding of the invention. In most packaging circumstances, the bags take on- -and indeed are intended to take on- -an advantageous custom shape defined by the object (s) they protect and the container (s) into which they are placed.

It will be understood that one of the fundamental aspects of the invention is the use of the insulating material to moderate the temperature on the exterior of the bag as the foamable compositions form the foam. As noted above, commonly used foamable compositions- -although certainly not the only ones- -include isocyanate components and polyol components, which, when reacted in the proper proportions, generate a heat of reaction sufficient to raise the temperature of the expanding foam to about 200-210°F in the foam core and about 140-160°F on the foam surface, while also generating very hot water vapor, or even steam. Although pain sensations can and do differ on an individual basis, and also depend somewhat on the nature and heat conductivity properties of the surface being touched, a skin temperature of about 46°C to 50°C is considered to represent the point at which a human touch will be perceived as painfully hot.

Thus, the invention can be considered a foam-in-bag packaging cushion in which the foam precursors comprise isocyanates and polyols and wherein the insulating characteristics of the bag material sufficiently moderate the transfer of heat generated by the reaction of isocyanate components and polyol components to keep the temperature of the outer surface of bag to a temperature that does not create a pain sensation when touched.

As also noted above, and independent of human touch or other manual handling considerations, these insulating characteristics also provide the capability to use foam-in- place packaging with certain items which, because of their heat-sensitivity, could not be packaged using more conventional foam-in-place techniques.

A number of materials are suitable for such thermal insulation. In the invention, three such materials are presently preferred based on a number of factors such as cost, ease of handling, and incorporation into present bag forming techniques and equipment. It will be understood, however, that these materials are exemplary, rather than limiting, of those that could be incorporated into the invention.

The first preferred material is a polyolefin foam broadly designated at 30 in the cross-sectional views of Figure 2 and 6. In a more preferred embodiment, the polyolefin foam is a polyethylene foam laminated to a polyethylene sheet 31. Both a polyethylene foam, and an appropriate foam laminated to polyethylene sheet are available from a number of sources, including Sealed Air Corporation, Park 80 East, Saddlebrook, New Jersey 70663.

Figure 7 illustrates another preferred material, namely a plastic encapsulated air bubble material broadly designated at 32. Such air bubble material is available from several sources, and in a more preferred embodiment comprises the laminated structure shown in Figure 7 in which the air containing structures 33 are formed in a sheet 34 of thermoplastic material which in turn is laminated to a second sheet 35 of the same or similar thermoplastic material which encapsulates the air in the structures 33. Such sheets of encapsulated air bubbles are perhaps most familiar as a packaging and cushioning material, and it is also available from Sealed Air Corporation, among others. The polyethylene foams described above are well-known in the art and an appropriate structure in terms of weight, thickness, cell structure and porosity can be selected without undue experimentation. U.S. Patent Nos. 5,348,984 and 5,462,974 both to named inventor Lee, are exemplary of more recent foam compositions and manufacturing methods, and are incorporated entirely herein by reference.

The preferred materials for the bag can also include other desired properties or compositions, one of which is the presence of an antistatic composition. Such antistatic compositions (including antistatic coatings) are generally well-known in the art and commercially available. Thus, an appropriate one can be selected without undue experimentation. Such antistatic properties are attractive to end users who package static-sensitive goods such as certain electronic components.

In addition to the bag precursors set forth in the copending '981 application, and as set forth in some of the patents noted in the background portion of the specification and incorporated herein by reference, there are several automated and semi-automated methods and related devices for forming a bag and filling it with a foamable composition. Because operators often handle the cushions made by these devices, and do so while the foam is rising and generating heat, the insulating characteristics of the present invention are similarly useful for automated and semi- automated applications. The most common techniques include forming a bag from two separately fed sheets of stock material, forming the bag from a center- folded stock material, or from a tube. The invention can be incorporated with any such manufacturing method. Thus, Figures 1 and 3 illustrate bags 20 and 36, respectively, that have been formed from two separate sheets and as a result are closed with four sealed edges. These sealed edges are designated at 24 through 27 in Figure 1 and as 37, 40, 41, and 42 in Figure 3. Because most polyolefins are thermoplastic, heat seals are most common. It will be understood, of course, that other sealing techniques (e.g. adhesives, adhesive tapes, mechanical fasteners) can be incorporated as otherwise desired or necessary. Figure 4 illustrates a third embodiment broadly designated at 43 which is formed from a center folded stock of the insulating material so that the center fold forms one closed edge 44 of the bag while the remaining three edges 45, 46, and 47, are sealed edges. Figure 5 illustrates a cushion broadly designated at 50 which has been formed from tube stock so that two of the edges 51 and 52 represent the edges of the tube, while the transverse edges 53 and 54 are sealed edges.

Any appropriate sealing technique can be used for any of the sealed edges described above. If thermoplastic materials such as polyethylene and other thermoplastics are used for the insulating bag material 30, however, heat seals are most convenient .

Figures 1, 3, and 4 also illustrate that the insulated cushions according to the present invention comprise means for permitting gases to ventilate to and from the bag.

Figure 1 illustrates that in the bag 20, the ventilation means comprises an unsealed portion 28 along the otherwise sealed edge 24 of the bag 20. Figure 3 illustrates that in the bag 36, the ventilation means comprises a panel 48 that is permeable to gases, but prevents substantial passage of foam and foam precursors. The nature and use of such a panel is set forth in copending application Serial No. 08/843,275, filed concurrently herewith for "Gas-Permeable Foam-In-Bag Packaging System, " the contents of which are incorporated entirely herein by reference.

In a third embodiment and as illustrated in Figure 4, the ventilation means in the bag 43 comprises a puncture opening which in Figure 4 is illustrated as the group of small openings 55 which can be appropriately formed by passing the bag material 30 (e.g. Figure 2) over a device such as a spiked roller. Such a system is described in the copending and incorporated '981 application referred to above . In Figure 5, the opening is illustrated as a mechanically formed slit 56 in one of the folded edges of the sealed tube that forms the bag 50. The slit 56 can also be formed in one face of the bag as may be useful or necessary in other circumstances. As set forth in the field and background, a thermally insulated bag offers the advantage and capability for being handled comfortably by persons in spite of the heat being generated as the foamable composition foams. Thus, the invention is useful with all sorts of foam-in-bag systems, including those in which the foam precursors are separately maintained in the bag during storage, rather than being immediately mixed as the bag is formed. As a result, the packaging operator can simply take one of the bags, mix the ingredients by hand (or with some simple device) , and then place the expanding bag and foam into a package for cushioning purposes. A number of such appropriate bag structures are set forth in copending application Serial No. 08/626,981 filed April 3, 1996 for "Foam-In-Bag Packaging System, " which is commonly assigned with the present invention and which is incorporated entirely herein by reference. Such a bag structure is illustrated in Figures 8, 9, and 10 herein. In these embodiments the bag, broadly designated at 60 (Figure 8) is formed of two sheets of plastic film material 61 and 62 (Figure 10) . As in the previous embodiments, the bag material 61 and 62 has insulating characteristics that sufficiently moderate the transfer of the heat generated by the reaction of the foam precursors to keep the temperature on the outer surface of the bag 60 below the expected pain threshold for human touch as the foam precursors react to form foam. The bag includes at least one frangible seal, two of which are illustrated at 63 and 64 in Figure 9. The frangible seals 63 and 64 define separate interior cells 65 and 66 in the bag 60 that in turn define a single cell bag when the frangible seals 63 and 64 are broken. A first foam precursor 67 is in one of the interior cells 65, and a second foam precursor 70 is in the second of the interior cells 66. As a result, after the frangible seals 63 and 64 break, the separate cells 65 and 66 together with the remainder of the bag 60 form an interior cell in which the first and second foam precursors 67 and 70 can continue to mix, react, and rise to eliminate precursor residue and permit the resulting foam to expand and flow properly within the resulting interior cell of the bag 60. Typically, breaking the seal 63 allows the precursors to react and the foam to begin to generate, after which the rising foam breaks the seal 64^' and expands into the remainder of the bag.

In general, when the foam precursors first mix they are said to "cream", i.e. form a viscous mixture that tends to appear whitish in color. This creaming is followed relatively quickly by a rapid rising of the foam. The entire process typically takes about 20 seconds (depending on temperature and other variables) after which the foam reaches substantially its final size. The final hardening process takes several more minutes after observable rising has ceased. In related embodiment, the cells 65 and 66 can be formed of a second bag within the first bag 60 in which the second bag is formed of two sheets of second plastic material that are closed on all four side edges with those edges of the second bag that are not coincident with one of the edges of the first bag being frangibly sealed edges. It will be understood that the resulting structure is substantially identical to that illustrated in Figures 8, 9 and 10 but with two extra layers of plastic material forming the cells 65 and 66.

In yet another embodiment, two bags can be attached to one another along a frangible seal with one of the bags having at least one other frangible seal that divides it into the two cells 65 and 66. Again, it will be understood that a cross-section of such a structure is substantially identically represented by Figure 9.

In the drawings and specification, there have been disclosed typically preferred embodiments of the invention and, although specific terms have been employed, they have been used in a generic sense and descriptive sense only, and not for purposes of limitation, the scope of the invention being set forth in the following claims.

Claims

THAT WHICH IS CLAIMED :

1. A foam in bag cushion that is particularly suitable for temperature-sensitive considerations such as manual contact and handling during the generation of the foam cushioning materials from foam precursors, said cushion comprising: a bag formed of a flexible web material that insulates the outer surface of said bag against conductive heat transfer from heated contents inside said bag; and a foamable composition in said bag.

2. A foam in bag cushion according to Claim 1 comprising two overlying sheets of said flexible web material and four closed edges that together with said sheets define a sealed bag.

3. A foam in bag cushion according to Claim 1 wherein said flexible web material is selected from the group consisting of: polyolefin foam; coextruded polyolefin foam and polyolefin film; kraft paper; woven textiles; nonwoven textiles; polyolefin foam laminated to a polyolefin sheet; and plastic-encapsulated air bubble material.

4. A foam in bag cushion according to Claim 2 wherein said closed edges comprise four sealed edges.

5. A foam in bag cushion according to Claim 2 wherein said closed edges comprise one folded edge and three sealed edges .

6. A foam in bag cushion according to Claim 2 wherein said closed edges comprise two folded edges and two sealed edges .

7. A foam in bag cushion according to Claim 1 and further comprising means for permitting gases generated to ventilate to and from the bag.

8. A foam in bag cushion according to Claim 7 wherein said ventilation means comprises an unsealed portion along an otherwise sealed edge of said bag.

9. A foam in bag cushion according to Claim 7 wherein said ventilation means comprises a puncture opening.

10. A foam in bag cushion according to Claim 7 wherein said ventilation means comprises a panel formed of a material that is permeable to gases, but that prevents substantial passage of foam and foam precursors.

11. A foam in bag cushion according to Claim 1 and further comprising portions of said bag that are formed of a material other than said insulating material.

12. A foam in bag packaging cushion containing foam precursors in which the bag is formed of a material that has insulating characteristics that sufficiently moderate the transfer of the heat generated by the reaction of said foam precursors to keep the temperature on the outer surface of said bag below that which would create a pain sensation when touched.

13. A foam in bag cushion according to Claim 12 and further comprising means for permitting gases to ventilate to and from the bag.

14. A foam in bag cushion according to Claim 13 wherein said ventilation means comprises an unsealed portion along an otherwise sealed edge of said bag.

15. A foam in bag cushion according to Claim 13 wherein said ventilation means comprises a puncture opening.

16. A foam in bag cushion according to Claim 13 wherein said ventilation means comprises a panel formed of a material that is permeable to gases, but that prevents substantial passage of foam and foam precursors.

17. A foam in bag cushion according to Claim 12 wherein said flexible web material is selected from the group consisting of: polyolefin foam; coextruded polyolefin foam and polyolefin film; kraft paper; woven textiles; nonwoven textiles; polyolefin foam laminated to a polyolefin sheet; and plastic-encapsulated air bubble material.

18. A foam in place packaging system that is particularly suitable for manual contact and handling during the generation of the foam cushioning materials from foam precursors, said system comprising: a bag formed of two sheets of flexible plastic film material closed on all four side edges; said bag material having insulating characteristics that sufficiently moderate the transfer of the heat generated by the reaction of foam precursors to keep the temperature on the outer surface of the bag below that which would create a pain sensation when touched as the foam precursors react to form foam; a frangible seal that defines separate interior cells in said bag; a first foam precursor composition in one of said interior cells; a second foam precursor composition in another of said interior cells; and means for permitting gases to vent to and from said bag as the foam precursors form foam; whereby when said frangible seal is broken said separate cells thereby form an interior cell in which said first and second foam precursors can mix thoroughly and react properly to substantially eliminate precursor residue and permit the resulting foam to expand and flow properly within the resulting interior cell of said bag.

19. A foam in bag cushion according to Claim 18 and further comprising means for permitting gases to ventilate to and from the bag.

20. A foam in bag cushion according to Claim 19 wherein said ventilation means comprises an unsealed portion along an otherwise sealed edge of said bag.

21. A foam in bag cushion according to Claim 19 wherein said ventilation means comprises a puncture opening.

22. A foam in bag cushion according to Claim 19 wherein said ventilation means comprises a panel formed of a material that is permeable to gases, but that prevents substantial passage of foam and foam precursors.

23. A foam in bag cushion according to Claim 18 wherein said flexible web material is selected from the group consisting of: polyolefin foam; coextruded polyolefin foam and polyolefin film; kraft paper; woven textiles; nonwoven textiles; polyolefin foam laminated to a polyolefin sheet; and plastic-encapsulated air bubble material.

24. A foam in place packaging system that is particularly suitable for manual contact and handling during the generation of the foam cushioning materials from foam precursors, said system comprising: a first bag formed of two sheets of a first flexible plastic film material closed on all four side edges; said bag material having insulating characteristics that sufficiently moderate the transfer of the heat generated by the reaction of foam precursors to keep the temperature on the outer surface of the bag below that which would create a pain sensation when touched as the foam precursors react to form foam; a second bag within said first bag, said second bag being formed of two sheets of a plastic film material closed on all of its side edges; at least one frangible seal that divides said second bag into two cells; a first foam precursor in one of said cells; a second foam precursor in the other of said cells; and means for permitting gases to vent to and from said first bag as said foam precursors form foam; whereby when said frangible seals are entirely broken said first and second bags thereby form an interior cell in which said first and second foam precursors can mix thoroughly and react entirely to eliminate precursor residue and permit the resulting foam to expand and flow properly within the resulting interior cell of said bag.

25. A foam in bag cushion according to Claim 24 wherein said ventilation means comprises an unsealed portion along an otherwise sealed edge of said bag.

26. A foam in bag cushion according to Claim 24 wherein said ventilation means comprises a puncture opening.

27. A foam in bag cushion according to Claim 24 wherein said ventilation means comprises a panel formed of a material that is permeable to gases, but that prevents substantial passage of solids and liquids.

28. A foam in bag cushion according to Claim 24 wherein said flexible web material is selected from the group consisting of: polyolefin foam; coextruded polyolefin foam and polyolefin film; kraft paper; woven textiles; nonwoven textiles; polyolefin foam laminated to a polyolefin sheet; and plastic-encapsulated air bubble material.

29. A foam in place packaging system that is particularly suitable for manual contact and handling during the generation of the foam cushioning materials from foam precursors, said system comprising: a first bag formed of two sheets of a first flexible plastic film material closed on all four side edges; a second bag adjacent said first bag, said second bag being formed of two sheets of a second plastic film material closed on all four side edges, one edge of said second bag being joined to one edge of said first bag; said first and second bag materials having insulating characteristics that sufficiently moderate the transfer of the heat generated by the reaction of foam precursors to keep the temperature on the outer surface of the bags below that which would cause a pain sensation when touched as the foam precursors react to form foam; a frangible seal between said first and second bags; at least one frangible seal that divides said second bag into two cells; a first foam precursor in one of said cells; a second foam precursor in the other of said cells; and means for permitting gases to vent to and from said first bag as said foam precursors form foam; whereby when said frangible seals are broken said first and second bags thereby form an interior cell in which said first and second foam precursors can mix thoroughly and react properly to eliminate precursor residue and permit the resulting foam to expand and flow properly within the resulting single interior cell of said bag.

30. A foam in bag cushion according to Claim 29 wherein said ventilation means comprises an unsealed portion along an otherwise sealed edge of said bag.

31. A foam in bag cushion according to Claim 29 wherein said ventilation means comprises a puncture opening.

32. A foam in bag cushion according to Claim 29 wherein said ventilation means comprises a panel formed of a material that is permeable to gases, but that prevents substantial passage of solids and liquids.

33. A foam in bag cushion according to Claim 29 wherein said flexible web material is selected from the group consisting of: polyolefin foam; coextruded polyolefin foam and polyolefin film; kraft paper; woven textiles; nonwoven textiles; polyolefin foam laminated to a polyolefin sheet; and plastic-encapsulated air bubble material.