2. Discussion of the Related Background Art The prior art discloses numerous disposable beverage containers having various types of self-contained cooling devices therein. To date, however, most cooling devices have been unduly complicated and/or expensive. One reason for the complexity of each of the devices invented thus far has been the need to construct a mechanism to activate the cooling process upon demand. To accomplish this task, some of the prior art utilizes various ways of attaching the cooling device to the flip-top tab portion of the beverage container. Such a construction compromises the effectiveness of the cooling apparatus and seriously limits the type of cooling devices which may be incorporated into beverage containers.

At the present time there are several patents, and a number of applications for patents, for pressure responsive valves and other actuators designed to operate specifically with self-cooling devices, such as those designed by and for applicant Thermal Product Developments, Inc.

In production, a typical self-cooling device would be inserted into an industry standard beverage container before or during the filling operation, and would be expected to remain in a static state, loaded but not discharged, until it is desirable to initiate the cooling process upon the release of pressure, which occurs when the container is opened.

The chilling mechanisms under discussion have traditionally been made from metals or other rigid materials for use with beverage containers or other applications where a pressurized environment could be maintained.

To facilitate integration, the prior art in valves for the chilling mechanism has necessarily utilized compatible materials. Because of that, all were equally rigid in construction, and fabrication required a number of specific metalworking operations. Such intricacies of production were reflected in their attendant costs and time required for manufacture.

Because all related costs would ultimately be passed on to the consumer, it became expedient to produce a more efficient design, one which would be as inexpensive to manufacture as possible, while still providing the requisite refrigeration.

As a result of ardent research, Thermal Product Developments, Inc. has advanced the state of the art for self-chilling mechanisms, and their efforts have shifted to the use of film materials for the entire Device. The use of film materials allows the cost of manufacture to be reduced by orders of magnitude, and production to be increased accordingly.

It became quickly apparent that the obvious benefits of making self- chilling mechanisms from film materials would only be realized if the necessary valves were to be made from equivalent materials, such that would allow for easy and practical integration into the finished product. Additionally, it was equally clear that absent any other method of detection of the opening of the container, said valve would of necessity be a pressure responsive valve.

U. S. Pat. No. 4,911,740 (Schieder 1990) discloses a self-contained cooling device in which a cooling effect is produced by causing a refrigerant liquid to

evaporate under reduced pressure in a first sealed chamber and in the process absorb heat from its surroundings. The resulting refrigerant vapor is then adsorbed or absorbed by a desiccant housed in a second, separate chamber. To achieve an effective cooling action, both the evaporative housing and the desiccant or sorbent housing must be maintained at a vacuum pressure level. The desiccant housing, in particular, must have a substantial vacuum condition.

A critical element is the pressure activated valve that separates the two chambers. The valve disclosed in U. S. Pat. No. 4,911,740 (Schieder 1990) includes a valve seat and a sealed pressurized chamber, a portion of which comprises a flexible diaphragm biased into a first position against the valve seat by the pressure in the chamber, thereby closing the valve. A dissolvable plug is in communication with the pressurized chamber for compromising the seal of the chamber upon the plug's dissolution, after which the diaphragm moves into a second position away from the valve seat upon the release of pressure from the chamber thereby opening the valve.

There remains a specific need, however, for pressure-activated valves having improved reliability and improved sealing properties, for use in self- contained cooling devices for beverage containers, especially for pressure- activated valves that are simple and inexpensive to construct. The present invention satisfies these and other needs and provides further related advantages.

SUMMARY OF DISCLOSURE OF THE INVENTION In order to clearly understand the operation of the valve, it is necessary to review the operation of the Self Chilling Device, hereafter referred to as the "Device"2, as designed by Thermal Product Developments, me. and illustrated in FIGS. 1-3.

Operation is initiated by the release of a refrigerant, typically water, into one or more areas each containing a wicking material maintained under vacuum, a

barrier material on one side between the wicking material and the beverage to be cooled, and a porous insulating layer or layers on the other side which is impenetrable by the refrigerant in a liquid state but allows the passage of vapor into the next layer of the cooling device. The liquid in the wicking material evaporates from the inner surface of the barrier material, passes through the liquidproof insulating layer, and is adsorbed into a sorbent. The process of evaporation and adsorption removes heat from the beverage which is subsequently stored temporarily in a heat sink material, typically a phase change material which can store most of the transferred heat as latent heat.

Any valve intended to operate with such a design would have to maintain indefinite separation between the refrigerant and the vacuum packed wicking material 3 as long as the product were unopened, with no degradation of the vacuum condition. It then would have to release the refrigerant into the wicking material concurrently with the opening of the can and its attendant release of pressure.

The Film Valve 4 accomplishes the separation in the following manner : The refrigerant required for the cooling process to operate would be enclosed, prior to activation, in a separate space designed so that, when the refrigerant is released into the wicking area, the integrity of the vacuum sealing of the entire cooling device is preserved. This refrigerant holding space shall be referred to herein as the"Refrigerant Bag". The Refrigerant Bag can best be constructed as a blister formed between the plastic film layers which contain the wicking material and other parts of the cooling device, but sealed separately. The Refrigerant Bag would be positioned in such a way as to allow the refrigerant to be distributed readily, upon activation, into the wicking area 5 of the invention.

Surrounding the refrigerant, and sealing it between the layers of film, thus isolating it from the evacuated wicking materials, would be an enclosing circle 10 where the two film layers would be joined 10 in a manner that allows the

separation between the Refrigerant Bag and the wicking area to be breached upon, and only upon, activation caused by a pressure decrease such as that caused by opening the beverage container.

In such a state, the cooling device could be stored indefinitely while waiting for the container to be opened, because, without activation, the refrigerant would be unable to penetrate the sealed area and enter the wicking material, so the cooling process could not begin.

Such a joint 20 could be accomplished in several ways. In one embodiment, the two layers of film would be partially heat sealed, fusing only enough to provide a fluid tight enclosure, but still maintaining the ability to separate upon the application of appropriate force.

An alternate embodiment would involve the use of an adhesive agent.

Said agent could take several forms, either a double-faced tape, or sealant applied as a viscous liquid and subsequently hardening in place. In either case, the object of the adhesive would be to isolate the water from the wicking material.

An alternate embodiment involves the use of a firm heat seal between the Refrigerant Bag and the wicking area, into which one or more channels for refrigerant flow are inserted. A hollow tube, sealed at one end, is placed next to channel openings and inserted into the refrigerant at the other end. The refrigerant cannot flow out of the Refrigerant Bag until the tube is broken, allowing the refrigerant to flow from the Refrigerant Bag into the channels.

Located against or near the Refrigerant Bag, and co-packaged with it, would be an additional separate film bag referred to herein as the"Trigger Bag" 40.

The Trigger Bag could be placed either inside or outside of the overall package, but in either case would share a common wall with either the Refrigerant Bag or, if a hollow tube embodiment is used, a separate film bag containing the hollow tube. The Trigger Bag could be attached in the form of a heat sealed patch against the film comprising part of the exterior of the cooling device, should production of that method prove to be more efficient. By using a patch, production would be rapid and the Trigger Bag would be automatically properly positioned.

If the Trigger Bag were located internal to the cooling device, it could be made of a tenacious but expandable film, such as polyethylene, and of such a thickness that were pressure applied to it internally, it would stretch without compromising the integrity of the film.

If its position were outside of the cooling device it would be made of the same base material comprising the cooling device.

In one embodiment, part or all of the outer wall of the Trigger Bag, between the interior of the Trigger Bag and the outside, would be an opening constructed such that gas could pass through in either direction but liquid could not enter into the Trigger Bag. This part of the outer wall of the Trigger Bag could consist of one or more very small holes, or of an open area covered by an appropriate microporous material, which could be strengthened by a porous backing or covering. The opening would typically be positioned so that, when the container is about to be opened, the opening would be in the air-or gas-filled head space at the top of the container. The opening could be located in such a manner that when the cooling device were placed (FIG. 3) within the can during the production cycle, its location would be either at the top of, or the bottom of, the can. Alternatively, a simple piece of film covering the orifice and extending to either the top or bottom of the Device could easily serve as conduit for gas passage simplifying the location of the Water Blister.

In addition, in the ideal embodiment, the Trigger Bag would contain a simple plastic Spacer 50 of such a shape and of sufficient rigidity that it would hold the film, constituting the walls of said bag, apart, even though substantial external pressure were to be applied against those walls. Critical to the operation of the insert would be the ability of the Spacer to maintain separation of the film, but any one of a multiplicity of shapes would be acceptable. In addition, said Spacer 50 could even be made of sponge like material.

In alternative embodiments, the Trigger Bag could initiate activation by producing a volume of carbon dioxide or other harmless gas. It could contain water and two harmless chemicals which would be kept separate prior to activation, either in multiple compartments or by some other method, and would produce the activating gas when combined.

In one gas-generating embodiment, the Trigger Bag could consist of two bags. One bag would be a separate plastic film bag filled with a measured amount of water, which would be easily ruptured and made to release its contents upon the application of moderate external pressure. This bag could also be formed by the fusion of two layers of plastic film. The pressure required for separation would be quite moderate. Included within the bag would be a small amount of water and, if appropriate, a sharp item designed to facilitate the puncture of the bag via impalement, upon the application of two atmospheres of pressure or more, and the release of its contents into the larger Trigger Bag. The other would contain a small amount of powder comprised of two separate and distinct agents.

The first agent would be bicarbonate of soda or any similar innocuous material capable of producing carbon dioxide, or other hannless gas, if activated by contact with a suitable acid. The second would be an acid of sufficient strength to react with the first powder, but also innocuous in nature, such as citric acid. Both powders would be anhydrous, and because of their totally dry condition would not react upon contact and could be easily co-mingled during manufacture without the

risk of activation. Because of their powder form, said agents could be pre-formed into solid tablets of carefully metered components. Such a form might facilitate the assembly process.

In another gas-generating embodiment, the bag containing the water within the Trigger Bag could be replaced by a sponge like material, or any material capable of absorbing and retaining water until compressed, under which condition it would be capable of releasing the contained water. The sponge like material could be inserted within the Trigger Bag in a charged condition, with a pre-measured amount of water contained within its interstitial spaces. The reacting chemicals could be enclosed in or coated with a water-soluble coating, similar to that used to coat medicine tablets. Such coatings would melt when placed in direct contact with water, but would remain impervious to water vapor which could be present in the Trigger Bag as the result of evaporation from the water in the sponge material.

In another gas-generating embodiment, the reacting chemicals could be contained within an appropriate semi-porous membrane and the water could be located inside the Trigger Bag but outside the membrane. The water would be unable to penetrate the membrane unless subjected to substantial pressure, typically around two atmospheres or greater. In addition, said membrane would be porous to the gas subsequently generated by contact between the water and the chemicals.

The cooling device may be affixed to a beverage container or integrated into a beverage container.

Other features and advantages of the present invention will be set forth, in part, in the description which follows and the accompanying drawings, wherein the preferred embodiments of the present invention are described and shown, and in part will become apparent to those skilled in the art upon examination of the

following detailed description taken in conjunction with the accompanying drawings, or may be learned by practice of the present invention. The advantages of the present invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appendent claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a self-contained pressurized cooling device with part of the outer surface cut away to reveal the layers underneath.

FIG. 2 is a first alternate embodiment of the valve, wherein the water blister and inner bag 4 share a common wall 20 with the cooling device 2.

FIG. 3 is a cutaway view of a standard beverage can containing the cooling device 2 in one possible orientation.

FIG. 4 is a component view of a preferred embodiment of the flexible self- cooling beverage pouch.

FIG. 5 is a cross-sectional View A of the preferred embodiment shown in FIG. 4 of a flexible self-cooling beverage pouch valve assembly.

FIG. 6 is a component view of a preferred embodiment showing a liquid reservoir and the pressure responsive valve assembly in close proximity to one another, separated by a small tubular structure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS AND BEST MODES FOR CARRYING OUT THE INVENTION Detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for claims and as a representative basis for

teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.

Certain terminology is used throughout the specification for convenience in reference only and is not to be limiting. For example, the word"absorption" refers to the occurrence of a substance (e. g., water vapor) penetrating the inner structure of another (the absorbent). Also, the word"adsorption"refers to the occurrence of a substance (e. g., water vapor) being attracted and held onto the surface of another (the adsorbent). The words"absorption"and"adsorption" include derivatives thereof. The word"sorbent"refers to a material that is either an absorbent and/or an adsorbent.

As shown in FIG 5, materials are layered to create a valve for the cooling device.

The casing and the cover are constructed from a barrier film material that is impervious to air and moisture so as to provide the cooling device 2 with a suitable shelf-life (to allow for several months or even years of storage/inactivation prior to use). Useful materials have an oxygen transmission rate (OTR) preferably less than about 1 cm3/m2/day, more preferably less than 0. 1 cm3/m2/day, and most preferably less than 0. 01 cm3/m2/day. Thevapor transmission rate of useful materials is preferably less than about 2 g/m2/day, more preferably less than 1 g/m2/day, and most preferably less than about 0. 1 g/n2/day.

Suitable materials for the casing include thermoplastic materials. Suitable materials for the cover include a metallicized plastic laminate or a metal foil plastic laminate. Preferred materials for the cover include flexible films such as those produced by the Rexam Corporation located in Bedford Park, Illinois, and Toyo Aluminum located in Osaka, Japan.

The sorbent layer of the cooling device 2 preferably is formed of an absorbent material dispersed on, impregnated in, affixed to, or otherwise combined with a porous support material. The porous support material preferably has a high pore volume, and therefore a high surface area, to accommodate the absorption of large amounts of liquid refrigerant, in vapor form, by the sorbent.

The pore volume is expressed in units of volume per unit mass. The porous support material has a pore volume of at least about 0.8 cc/g, more preferably at least about 1 cc/g, and even more preferably at least about 1.5 cc/g.

In order to accommodate high absorption levels of liquid refrigerant, it is also important to control the average pore diameter and pore size distribution of the porous support material. The average pore diameter is preferably at least about 1 nanometer, and typically in the range from about 1 to about 20 nanometers. The average pore diameter distribution is such that there are very few pores having a diameter of less than about 0.5 nanometers. The porous support material can be selected from virtually any material having the above- identified properties. Preferred materials for the porous support material include activated carbon and silica.

The hydrophilic region of the insulating material has pores with a relatively large diameter, not less than 10 mm in diameter, on average. The large pores of the hydrophilic region encourage the rapid flow of liquid refrigerant into the material. The hydrophobic region has pores of a relatively small diameter, typically less than about 2 mm in diameter, so that the un-vaporized liquid refrigerant is inhibited from passing into the sorbent section, but rather only the vapor from the liquid refrigerant is directed into the sorbent section.

The liquid barrier may be constructed of any suitable material, such as polyethylene or polypropylene film. When the liquid refrigerant is water, suitable wicking materials include hydrophilic materials such as microporous metals,

porous plastics (polyethylene, polypropylene), cellulose products, sintered heat pipe material, or glass paper, and the like.

In some embodiments, there is a rupturable membrane made of plastic, typically polyethylene, that is filled and heat sealed along its edges enclosing the liquid refrigerant. The liquid refrigerant should have a high vapor pressure at ambient temperature so that a reduction of pressure will produce a high vapor production rate. In addition, the liquid refrigerant has a high heat of vaporization.

The vapor pressure of the liquid refrigerant at 20°C is typically at least about 9 mm Hg, preferably at least about 15 or 20 mm Hg. Suitable liquid refrigerants include various alcohols, such as methyl alcohol or ethyl alcohol; ketones or aldehydes such as acetone and acetaldehyde; and hydrofluorocarbons such as C318,114,21,11,114B2,113,112,134A, 141B, and 245FA. The preferred liquid refrigerant is water because it is plentiful and does not pose any environmental problems while providing the desired cooling characteristics.

DETAILED DESCRIPTIONS OF CERTAIN PREFERRED EMBODIMENTS One embodiment of the beverage cooler valve is a pressure-actuated device that will release a liquid from a sealed reservoir into the cooling section of the cooler. A preferred embodiment of the valve is a multilayered system composed of barrier layers, a membrane material layer, and a porous support layer. Within the system is a set of open cell compressible sponges and a needle.

A description of these materials and the assembly of the valve follows. (FIGS. 4- 6).

A. Description of Valve Components 1. Barrier Film Layer The barrier layer in the beverage cooler is used to maintain the near- vacuum pressures at which the beverage cooler operates best. It is capable of

being heat sealed at a variety of temperatures while still maintaining a vacuum within the cooler. One preferred embodiment of this barrier is Rexam (Rexam, catalog #0652/500, United Kingdom).

2. Membrane Layer The membrane in the valve is a material that is microporous and hydrophobic. It must be impermeable to liquids under external pressures found in the beverage manufacturing process so that the beverage in the can does not leak through the membrane. The membrane must also be capable of heat-sealing to both the barrier and support layers. One membrane material of choice is Porvair (Porvair International Limited, United Kingdom).

3. Support Layer The support layer provides a strong backbone to the membrane material, which can be weak and easily torn. In one preferred embodiment, the material used in the valve is 100% Ripstop nylon, available at fabric stores.

4. Sponge material The valve contains two equally sized sponges that hold open the compartment (described below) by filling with air. During the manufacturing process, a high pressure in the can is introduced. When the can is opened, this pressure is released. However, the microporous membrane cannot equilibrate the pressure inside the compartment quickly enough. The air trapped inside the compartment rushes to escape through the pores in the membrane, causing a slight movement of the compartment. This slight movement is enough to snap the needle and release the liquid into the cooling section of the cooler. In one preferred embodiment, the sponges may be cut from an open celled, easily compressible material. In one preferred embodiment, the material currently used in the valves may be 1/4 inch thick Scrim available at automotive upholstery shops.

5. Needle

The needle may be a thin walled tube about 1 1/4 inch sealed at one end with any adhesive or epoxy capable of bonding to it and sealed at the other end into the liquid reservoir. The needle can be glass or a brittle plastic capable of quickly snapping at a weak point. In one embodiment, a needle cut from a disposable glass pipette may be used (VWR Scientific Products, catalog #53499- 630). A weak point can be created on the needle by scoring it with a sharp blade.

When the needle snaps at its weak point, the liquid in the reservoir is released through this break into the cooling section of the beverage cooler.

B. Assembly of Valve The membrane and support layers (preferredly made of Porvair and nylon) may be cut into patches of material of roughly equivalent size, for example, 1 inch x 1 % inches (FIG. 6). The first step in making the valve for the beverage cooler involves creating the compartment that will contain the sponges. The compartment is located at one corner of the beverage cooler (FIG. 4). There is a small pocket at the top of the compartment, which will hold the top tip of the needle in place. There is also a channel directly opposite the pocket that allows the needle to enter the compartment (FIG. 6). Both the pocket and the channel are located between the Rexam layers only and are about l/4 inch wide.

The compartment is made by sealing all four layers at once using an Accu- Seal 50 (Accu-Seal Corporation, San Diego, CA). The pocket and channel should be located on the 1 1/4 inch long side of the compartment (FIG. 6). To create the pocket and channel between the Rexam layers, a strip of a doubled layer of Rexam should be placed between the Rexam layers at the location desired. The strip of doubled Rexam prevents the Accu-Seal from sealing the Rexam closed in these areas, but has no effect on the Porvair and nylon layers sealing to each other.

It is best to seal three sides of the compartment, leaving one side open. At this point, the sponges should be inserted between the Porvair and Rexam layer.

They should be spaced in the compartment so that there is room between them for the needle to slide through (although the needle will be in a different plane, between the two Rexam layers).

In one preferred embodiment, the sponges may be about 1/4 inch x 5/8 inch.

After the sponges are inserted, the fourth side of the compartment is sealed. From the inside of the Rexam bag, the liquid reservoir is placed so that the needle enters the compartment through the channel and is held in place at the opposite end of the compartment by the pocket. The scored point of the needle should face the Rexam layers of the compartment. At this point, the valve section of the beverage cooler is complete.

C. Use of the Valves To use the valve correctly, a complete valve must be placed in a sealed chamber which is pressurized with air to about 45 psi. The pressure should then be allowed to remain there. When the pressure in the chamber is quickly released, because the microporous membrane material cannot equilibrate the pressure inside the compartment to that outside the compartment quickly, the membrane moves slightly. This movement is enough to snap the scored needle. The snapped needle then releases the liquid from the reservoir, and it then may travel down the channels and onto the wicking material.

INDUSTRIAL APPLICABILITY The Self Chilling Mechanism could be inserted into a beverage container immediately before the introduction of the beverage and sealed with the placement of the lid on the container.

As a result of a post-fill gas purge as well as the agitation of the beverage during the filling operation, a substantial pressure spike would be generated within the container. Such pressure would produce a gas bubble which would occupy space either at the top of the can, or, conversely, were the can to be inverted, at the bottom of the can.

Because the opening through the wall of the Device and into the Inner Bag would be either at the top or the bottom of the can, or so conducted by a secondary film covering, it would be co-located with, and exposed to, the gas charge at the relative end. Such placement would allow the can to be filled and either maintained upright, or inverted, as best suited the specific application.

In the preferred embodiment, which uses a gas-permeable, liquid- impermeable opening between the Trigger Bag and the outside, a finite amount of gas would slowly begin to pass through the opening into the separated space provided by the plastic Spacer within the Trigger Bag, as a result of the pressure of the gas charge, and the exposure of the orifice to that gas-filled area. The gas migration would continue until the pressure of the gas contained within the walls of the Trigger Bag, would be at equilibrium with the gas pressure contained in the head space of the container.

Because flow through the opening 40 into the Inner Bag (FIGS. 1 & 3) would be very restricted, it would take a substantial time for the gas to migrate into the Trigger Bag through the opening, and, correspondingly, it would take a substantial time for the gas to escape when the container is opened and the pressure is suddenly reduced to ambient.

Since it is reasonable to expect that a substantial time would always elapse between the filling operation and the final sale to, and opening of, the container by the consumer, sufficient gas would migrate into the Trigger Bag to equilibrate

the pressure in time for the cooling device to be ready for activation. Initial equilibration is expected to take less than one hour.

When the container is opened, the return to ambient atmospheric pressure would represent a sudden loss of pressure external to the cooling device and the Trigger Bag. The sudden differential between the then greater internal pressure within the Trigger Bag and the reduced outer pressure would immediately cause the Trigger Bag to expand, and, if the thin film alternative were used, would readily stretch to accommodate the suddenly rising internal pressure.

If located outside of the Device proper, the more rigid film would contain the rise in pressure, transferring the force inwardly. However, in either case the resultant pressure application would essentially be the same.

It is important to note that inflation could not take place as long as the can remained unopened because the pressure both within and without the Inner Bag would be equal. When the contained pressure is reduced to ambient, as caused by the opening of the can, the pressure differential then would become sufficient to immediately inflate the Trigger Bag.

In the gas-generating trigger embodiments, the pressure spike during the filling process would immediately mix the water and reacting chemicals.

Depending on the embodiment, the mixing could be caused by rupturing a water-containing bag in the Trigger Bag, forcing contraction of a sponge-like material containing the water or pressing the water through a semi porous membrane.

Upon mixing, the water would intermingle with the mixture of reagent and acid powders, immediately activating it and initiating a chemical reaction which,

when continued to completion, would generate a substantial amount of carbon dioxide gas at sufficient pressure to immediately fill the Trigger Bag.

However, in each of the gas-generating trigger configurations, the inflation of the Trigger Bag could not take place as long as the can remained unopened because the gas-generating reaction cannot take place until the pressure is reduced below a defined tllreshold. When the can is opened and the pressure outside the Trigger Bag is reduced to ambient, the reaction occurs and the pressure generated by the release of the carbon dioxide gas inflates the Trigger Bag.

An essential feature of the Film Valve is that the Trigger Bag rapidly inflates as the result of a pressure drop which occurs when the container is opened. Other methods may be used to cause this inflation, in addition to the differential inflation embodiments and the gas-generating embodiments described above.

The inflation of the Trigger Bag is used to allow refrigerant to flow from the Refrigerant Bag into the wicking area. Typically, the inflation will be used to breach the separation between the Refrigerant Bag and the wicking area.

Depending on the embodiment, the pressure and shape change caused by inflation can be used to rupture a weak heat seal, separate an adhesive seal, break a tube serving as a refrigerant conduit or cause some other breach or connection which allows refrigerant to flow into the wicking area.

As the consumer opens the pressurized beverage container, activation and operation would take place in the following sequence: When the container is opened, the pressure within the container would be immediately released, returning the can to atmospheric pressure. The pressure decrease causes the Trigger Bag to rapidly inflate. The inflation is used to allow

the refrigerant to flow into the wicking area. The vacuum in the wicking area helps to draw the refrigerant into the area rapidly. As the refrigerant enters the wicking area, it begins to evaporate and cooling begins.

At that time, the function of the pressure-sensitive actuator is fulfilled.

With such possibilities in mind, the invention is defined with reference to the following claims.