SELF-HEATING CONTAINER

CROSS-REFERENCE

[001] This application claims priority to U.S. Provisional Application Serial No.

60/736,485, entitled "Self-Heating Container", filed November 14, 2005, which is herein referenced and incorporated in its entirety.

BACKGROUND

1. Field of the Invention

[002] The present invention relates to a container, and more particularly, to a self- heating container.

2. Background of the Invention

[003] For today's on-the-go consumer society, it would be convenient for consumers to be able to heat beverages, such as coffee, tea, or milk, and food products, such as soup, quickly without having access to any conventional source of heat. Consumers would be able to have hot cup of coffee anytime, anywhere regardless of whether there is a coffee maker, kettle, or a microwave.

[004] Self-heating technology has been around for a while. A typical self-heating technology employs an exothermic reaction using two reagents, where one reagent is a solid material such as calcium oxide and the other reagent is a liquid such as water. Initially, the two reagents are separated by a barrier but when the heating is to be initiated, the barrier is broken and the two reagents are mixed together creating an exothermic reaction and thereby generating heat. [005] To date, many different containers using self-heating technology have been designed. For example, U.S. Patent No. 4,793,323 describes a self heating container which

includes an outer insulating envelope and a plastic material vessel provided inside the envelope, where the vessel is divided into an upper and a lower compartments separated by a membrane. The upper compartment holds a solid reagent and the lower compartment holds a liquid reagent. The upper compartment and the lower compartment are separated by an aluminum barrier which is thermally welded to a toroidal surface of the upper compartment. The container further includes a metallic inner container for holding a solid or liquid substance situated within the upper container. A breaking member is integral with the lower compartment and able to break the membrane when pressure is exerted against it. To generate heat, the container is turned upside down and a manual pressure is exerted on the bottom of the lower compartment which causes the barrier to break and the two reagents to mix, thereby generating heat A disadvantage of this container is that in assembly, placing and securing the membrane, which is a critical step, can be complicated, and sophisticated testing steps would be required to ensure that the seal is secure. Filling the lower compartment with water must be done with precision as any water present in the vicinity of the seal can adversely effect the quality of the seal.

[006] PCT Publication WO 2004/022450 describes a container which includes an outer container containing the beverage inserted in a beverage container. The solid reactant is arranged in the upper compartment annularly about the beverage receptacle. Water is arranged in the lower compartment. A breakable diaphragm extends substantially against the base of the first receptacle. A breaking device is provided within the second cpmpartment. A disadvantage of this container is that assembly is quite complicated. After the solid reactant is provided within the outer container, it must be moved out of the way using a complex spinning technology in order to make room for the beverage container. [007] U.S. Patent No. 6,502,407 describes a container which has an external cavity which has the heating means and an internal cavity which holds the beverage. The internal

cavity extends within the external cavity. The heating means includes calcium oxide placed in the internal cavity and water provided in the water chamber below the external cavity. The water chamber is separated by the external cavity through a lid. A plunger is affixed to a button on the base of the container. When heating is desired, the container is inverted and the button is pressed. The depression moves the plunger in a direction to push the lid open and the water is quickly released to mix with calcium oxide creating a reaction and generating heat. A disadvantage of this container is that it requires many of the parts to be sealed. Seals can be easily broken when the container undergoes a temperature change, jeopardizing the integrity of the container.

[008] U.S. Patent No. 6,266,879 describes a container which has a container body, a thermic module at one end of the body, and a closure at the other end of the body. The module has an elongated heat-exchanger portion that extends into the container body. The heat-exchanger portion has a corrugated or pleated wall to increase the surface area. A module cap is press-fit in the open end of the module body. A breakable barrier is adhesively attached to the open end of the module cap to seal a reactant inside. An actuator assembly is attached to the end of the container body and has an actuator button which is supported on spline-shaped fingers and further has a breakable actuator barrier. Pointed projections extend from the underside of outer actuator button toward the actuator barrier. To heat the substance inside the container, the user depresses the actuator button by exerting a force upon it which causes the fingers to puncture the barrier and causes the inner actuator button to move toward the barrier such that the distal end of the prong punctures the reaction barrier. Water flows through the barrier and mixes with solid reactant in the thermic module body. The container of the '879 patent has a complex design and too many parts. [009] Although various self-heating technology and self-heating container designs have been around for a while, self-heating containers have not be widely commercialized in

the marketplace. This is because none of the existing designs are sufficiently simple to enable manufacturing at a reasonable cost.

[010] The present invention overcomes one or more of the deficiencies of the prior art by providing a self-heating container that is simple in design and easy and cost efficient to manufacture.

SUMMARY OF THE INVENTION

[011] In one aspect, the preferred embodiments of the invention features a self- heating or self-cooling container which includes an outer container body which defines a first chamber, an inner container body which defines a second chamber, and a reactant vessel provided within the first chamber underneath the inner container body. The outer container body includes a first reactant. The inner container body includes a substance to be heated or cooled. The reactant vessel includes a second reactant. The first reactant and the second reactant are capable of reacting to generate an exothermic or an endothermic reaction. In a preferred embodiment, the first reactant is provided ammlarly around the inner container body to maximize the heat transfer to the substance. The reactant vessel is covered with a breakable barrier. The container further includes a breaking device provided within the first chamber between the inner container body and the reactant vessel. The breaking device is capable of breaking the barrier to release the second reactant into the first chamber to mix and react with the first reactant when activated.

[012] In one embodiment, the breaking device is a puncture ring substantially surrounding an outer bottom surface of the inner container body. For example, the breaking device may include multiple blades and a point. In another embodiment, the breaking device is disposed within the first chamber between the inner container body and the reactant vessel

in a spaced relationship and separates the first chamber into an upper compartment and a lower compartment. The breaking device is capable of breaking the barrier to release the second reactant into the upper compartment when activated. The breaking device includes an outer rim, a hub, and multiple spokes which extend radially from the hub to the outer rim. Ih another embodiment, the breaking device is secured to an outer surface of the lower portion of the inner container body and the breaking device includes an outer rim, an inner rim, multiple openings between the two, and a cutter extending from the inner rim. hi one embodiment, the breaking device has a rim separating the first chamber into an upper compartment and a lower compartment. The rim is sized and shaped to secure the reactant vessel within the outer container body and also to keep the first reactant substantially within the upper compartment. [013] In another embodiment, the invention features a container which includes an outer container body defining a first chamber, an inner container body defining a second chamber, and a reactant vessel secured to a lower end of the inner container body. The outer container body includes a first reactant. The inner container body is provided within the outer container body and includes the substance to be heated or cooled. The reactant vessel includes a second reactant capable of reacting with the first reactant to generate an exothermic or endotheπnic reaction. A breakable barrier covers a lower end of the reactant vessel. A breaking device is secured to a lower surface of the outer container body. The breaking device includes a piston wiper and at least one longitudinally extending pin capable of breaking the barrier to release the second reactant into the first chamber to mix and react with the first reactant when the breaking device is pushed toward the barrier and turned. [014] In still another aspect, the preferred embodiments of the invention features a container which includes an outer container body defining a first chamber, an inner container body defining a second chamber, an activator disposed at a lower surface of the outer container body, and a reactant vessel secured to the activator within the first chamber

underneath the inner container body. The outer container body includes a first reactant. The inner container body is provided within the outer container body and includes the substance to be heated or cooled. The activator includes a piston wiper. The reactant vessel contains a second reactant capable of reacting . with the first reactant to generate an exothermic or endothermic reaction. A breakable barrier covers an upper end of the reactant vessel. A breaking device is secured to a lower surface of the inner container body. The breaking device includes a serrated blade and is capable of breaking the barrier to release the second reactant into the first chamber to mix and react with the first reactant when the activator, along with the reactant vessel, is pushed toward the breaking device and turned. [015] The containers of the preferred embodiments of the present invention are simple in design and cost efficient to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS

[016] The foregoing, and other features and advantages of the invention, will be apparent from the following, more particular description of the embodiments of the invention and the accompanying drawings.

[017] Figure IA is a cross-sectional view of one embodiment of a container of the present invention prior to activation of the self-heating step. [018] Figure IB shows a perspective view of the container of Figure IA.

[019] Figure 1C shows a bottom view of the container of Figure IA.

[020] Figure ID shows a cross-sectional view of one embodiment of a container of the present invention.

[021] Figure IE shows a top view of a pull tab lid.

[022] Figure IF shows a cross-sectional view of the puncture ring of the container of

Figure IA.

[023] Figure IG shows a top view of the puncture ring of the container of Figure IA.

[024] Figure IH shows a bottom view of the puncture ring of the container of

Figure IA.

[025] Figure II shows a bottom view of a drinking lid of the container of Figure IA.

[026] Figure U shows a top view of a drinking lid of the container of Figure IA.

[027] Figure IK shows a top view of one embodiment of a breaking device of the present invention.

[028] Figure IL shows a bottom view of the breaking device of Figure IK.

[029] Figure IM shows a cross-sectional view of the breaking device of Figure IK.

[030] Figure 2 is an up-side down cross-sectional view of the container of Figure IA as the self-heating step is being activated.

[031] Figure 3 A is a cross-sectional view of one embodiment of a reactant vessel of the present invention

[032] Figure 3B is a cross-sectional view of one embodiment of a reactant vessel of the present invention.

[033] Figure 3C is a top view of the reactant vessel of Figure 3A.

[034] Figure 3D is a perspective view of the reactant vessel of Figure 3A.

[035] Figure 4 is a cross-sectional view of another embodiment of a container of the present invention prior to activation of the self-heating step.

[036] Figure 5 is a bottom view of the puncture ring included in the container of

Figure 4.

[037] Figure 6 is a cross-sectional view of another embodiment of a container of the present invention prior to activation of the self-heating step.

[038] Figure 7 A is a bottom view of the puncture ring included in the container of

Figure 6.

[039] Figure 7B is a top view of the puncture ring included in the container of Figure

6.

[040] Figure 8 is a cross-sectional view of another embodiment of a container of the present invention prior to activation of the self-heating step.

[041] Figure 9 is a bottom view of the container of Figure 8.

[042] Figure 10 is a cross-sectional view of another embodiment of a container of the present invention prior to activation of the self-heating step.

[043] Figure 11 is a bottom view of the container of Figure 10.

[044] Figure 12A shows a cross-sectional view of an embodiment of the inner container body.

[045] Figure 12B shows a top view of the inner container body of Figure 12A.

[046] Figure 12C shows a bottom view of the inner container body of Figure 12A.

[047] Figure 13 is a cross-sectional view of a portion of an embodiment of a container of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [048] Referring to Figure IA, in one embodiment of the present invention, a container 10 includes an. outer container body 12 defining a first chamber 13, an inner container body 14 defining a second chamber 15 disposed within the outer container body 12, and a reactant vessel 16 disposed within the first chamber 13. The inner container body 14 holds the beverage, food item, or other substance to be heated. A lid 2 covering the inner container body 14 maintains the substance inside the second chamber 15. It would be desirable to construct the inner container body 14 with a material having high thermal conductivity. For example, the inner container body 14 can be constructed of a metallic material such as aluminum or certain polymeric material such as polyolefin. In a preferred embodiment, the

inner container body 14 defines a second chamber 15 which is able to hold liquid capacity of greater than 100 mL and in a more preferred embodiment, liquid capacity of greater than 200 mL of liquid. The inner container body 14 and the outer container body 12 may be formed as a single, unitary structure, where the lip 17 of the inner container body 14 and the lip 19 of the outer container body 12 are continuous. Alternatively, the lip 17 of the inner container body 14 may be sealed with the lip 19 of the outer container body 12, using, for example, thermal welding or crimping. It would be desirable to construct the outer container body 12 with an insulating material to direct the heat towards the inner container body 14 and to keep the outside of the outer container body 12 from getting too hot for the consumer to hold. For example, the outer container body 12 can be made of an appropriate polyolefin. The outer container body 12 includes a protruding, flexible bottom 26. hi a relaxed state, the bottom 26 protrudes downward. However, the bottom 26 is made to be flexible such that it can be pushed upward towards the inner container body 14. The bottom 26 can be made as a single, unitary structure with the sides of the outer container body 14. For example, the bottom 26 and the outer container body 14 can be constructed as a unitary structure using a molding process such as injection molding or extrusion molding. These processes are well known to those skilled in the art. Alternately, the bottom 26 can be sealed to the inside surface of the outer container body 12, for example, using any welding process.

[049] In the embodiment of Figure IA, the reactant vessel 16 is disposed inside the outer container body 12, underneath the inner container body 14 in a spaced relationship. The outer surface 23 of the lower end of the reactant vessel 16 is secured to the inner surface 21 of the bottom 26. The reactant vessel 16 may be press fitted into the outer container body 12. Alternatively, the reactant vessel 16 may be attached to the bottom 26 using any sealing technology, including using an adhesive. The reactant vessel 16 is designed to hold one of the two reactants used to create a reaction which generates heat. For example, if water and

calcium chloride are the two reactants used to create an exothermic reaction to generate heat, the reactant vessel 16 may contain either water or calcium chloride. The reactant vessel 16 can be made out of any suitable material able to withstand heat such as polyethylene- terephtalalate glygol, polystyrene, or aluminum.

[050] Referring to Figures 3A-3D, in one embodiment, the reactant vessel 16 includes a flange 20 which extends circumferentially around the upper end of the reactant vessel 16. The flange 20 maintains the reactant vessel 16 snug within the outer container body 12 and also separates the first chamber 12 into two compartments, an upper compartment 22 and a lower compartment 24. The upper compartment 22 is designed to hold a reactant (the "first reactant") which is to react with the reactant provided in the reactant vessel 16 (the "second reactant"). If the second reactant provided in the reactant vessel 16 is calcium chloride as shown in Figure 1, the first reactant provided in the upper compartment 22 could be water. The flange 20 keeps all or most of the water from entering the lower compartment 24 before the self-heating step is initiated. In a preferred embodiment, the upper compartment 22 has sufficient amount of the first reactant such that when the container is inverted upside down as discussed below, the first reactant covers annularly the outer surface of the inner container body 14 to maximize the surface area of the inner container body 14 contacting the mixture of the first reactant reacting with the second reactant. This configuration provides efficient transfer of the heat generated to the substance to be heated. Although the present invention is described with the use of water and calcium chloride, other materials capable of generating an exothermic reaction can be used in accordance with the present invention. For example, water can react with calcium oxide or a blend of anhydrous magnesium chloride and calcium chloride. [051] The dimensions of the reactant vessel 16 shown in Figures 3 A and 3B are exemplary only and are not meant to be limitations for the reactant vessel 16.

[052] Referring back to Figure IA, the open, upper end of the reactant vessel 16 is covered with a breakable material which acts as a barrier to keep the second reactant from mixing with the first reactant before the self-heating reaction is activated. For example, the barrier 28 can be made of a foil such as an aluminum foil.

[053] In one embodiment, the lower end of the reactant vessel 16 is sized and shaped to fit snuggly within the bottom 26 of the outer container body 14, such that when the bottom 26 is pushed towards the inner container body 14, the reactant vessel 16 is also moved towards the inner container body 14. The lower end of the reactant vessel 16 can be fastened to the inner surface of the bottom 26 to maintain the two in relative positions. The lower end of the reactant vessel 16 includes a radius of curvature which coincides with the radius of curvature provided in the bottom 26. This configuration allows the bottom 26 to propel upward easily when force is exerted against it and flex back to its original position. [054] Referring to Figures IA ₅ IF, IG, and IH, the container 10 further includes a breaking device in the form of a puncture ring 30 disposed on the outer surface of the lower end 31 of the inner container body 14. The puncture ring 30 includes one or more star edges forming blades 34 and converging to a sharp point 31 sufficient to puncture the barrier 28. The distance between the point 31 of the puncture ring 30 and the barrier 28 is selected such that when the bottom 26 is pushed all the way up, the barrier 28 would come in contact with the blades 34 of the puncture ring 30. The puncture ring 30 can be made of any suitable material including a metallic material such as aluminum or a polymeric material. [055] Figures IK, IL, and IM show another embodiment of a breaking device 30'.

Similar to the breaking device shown in Figures IF, IG, and IH, the device 30' includes star edges 31 ' which form blades that converge into a sharp point 32'. In addition, the breaking device 30' includes multiple openings 33' which allow passage of water through from the lower compartment to the upper compartment.

[056] Referring to Figure ID, the container 10 includes a pull tab lid 2 shown in

Figure IE in detail, covering the open surface of the inner container body 14. The pull tab lid 2 can be made out of any suitable material, including aluminum. The container 10 further includes a snap-on drinking lid 4 shown in detail in Figures II and IJ. The drinking lid 4 includes an orifice to enable the consumer to consume the substance inside the container 10. [057] In one embodiment, the parts of the above-described container 10 are made of materials that can withstand the maximum temperature that would be reached from the exothermic reaction, which can be at least two hundred and fifty degrees Fahrenheit (250 ⁰ F). [058] To heat the substance provided in the container 10, the container 10 is inverted upside down as shown in Figure 2, and pressure is exerted on the bottom 26 to push the bottom towards the inner container body 14. The exerted pressure pushes the bottom 26 and the reactant vessel 16 towards the puncture ring 30. Once the puncture ring 30 contacts the barrier 28, the barrier 28 breaks open and the second reactant is released into the first chamber 13. The consumer shakes the container 10 which helps to mix the second reactant with the first reactant. The first reactant and the second reactant mix and generate an exothermic reaction which releases heat. The released heat heats the substance 7 provided inside the second chamber 15. After the substance is heated, the consumer can remove the pull tab lid 2, put the drinking lid 4 back on, and consume the substance.

[059] Referring to Figure 4, in another embodiment of the present invention, the container 40 includes an outer container body 42 defining a first chamber 43, an inner container body 44 defining a second chamber 45 disposed within the outer container body 42, and a reactant vessel 46. The outer container body 42 includes a protruding, flexible bottom 48. The reactant vessel 46 is disposed inside the outer container body 42, underneath the inner container body 44 in a spaced relationship and a breaking device in the form of a puncture ring 50 is disposed between the inner container body 44 and the reactant vessel 46.

The puncture ring 50 rests on a rib 52 provided radially along the inside surface of the outer container body 42. For example, the puncture ring 50 may be snap fit assembled into this position. The puncture ring 50 separates the first chamber into an upper compartment and a lower compartment.

[060] Referring to Figure 5, the puncture ring 50 has a wheel-like construction. The ring 50 has an outer rim 53, a hub 56, and multiple spokes 54 which extend radially from the hub 56 to the outer rim 53. Each spoke 43 has a blade-like edge 55. There is an opening between adjacent spokes 54. The opening allows the second reactant held within the reactant vessel 46 to pass through the ring 50 to mix with the first reactant residing within the first chamber 43. The hub 56 has a pointed end. The pointed end of the hub 56, along with the blade-like edges 55 of the spokes 43, are useful in puncturing the barrier 57 when they come in contact with the barrier 57. The puncture ring 50 extends the entire cross section of the first chamber 43 and the width of the outer rim 54 is substantially equal to or slightly greater than the distance between the outer container body 42 and the inner container body 44. The puncture ring 50 also either contacts the bottom of the inner container body 44 or is substantially close to the bottom of the inner container body 44. This construction keeps the second reactant substantially within the upper compartment of the first chamber 43. [061] Referring to Figure 6, in another embodiment of the present invention, the container 60 includes an outer container body 62 defining a first chamber 63, an inner container body 64 defining a second chamber 65 disposed within the outer container body 62, and a reactant vessel 66. The reactant vessel 66 is disposed inside the outer container body 62, underneath the inner container body 64 in a spaced relationship and a breaking device in the form of a puncture ring 70 is secured to the outer surface of the bottom of the inner container body 64.

[062] Referring to Figures 7A and 7B, the puncture ring 70 includes an outer rim 73, an inner rim 74, and a cutter 76. The puncture ring 70 includes multiple openings extending circumferentially between the outer rim 73 and the inner rim 74. The openings allow the second reactant held within the reactant vessel 66 to pass through the ring 70 to mix with the first reactant residing within the upper compartment of the first chamber 63. The cutter 76 comprises multiple, protruding blades 78 which extend from the inner rim 74 and converge into a sharp point 77. The sharp point 77, along with the multiple blades 78, can puncture the barrier 79 when they come in contact with the barrier 79. The puncture ring 70 extends the entire cross section of the first chamber 63 and the width of the outer rim 73 is substantially equal to or slightly greater than the distance between the outer container body 62 and the inner container body 64 and therefore keeps the first reactant within the upper compartment of the first chamber 63.

[063] Referring to Figure 8, in another embodiment of the present invention, the container 80 includes an outer container body 82 defining a first chamber 83, an inner container body 84 defining a second chamber 85 disposed within the outer container body 82, and a reactant vessel 86. The reactant vessel 86 contains a first reactant and includes a breakable barrier 83 covering the lower end of the reactant vessel 86 to keep the first reactant within the vessel 86. The reactant vessel 86 is integrated with the inner container body 85. The reactant vessel 86 and the inner container body 85 can be constructed of a single molded part. Alternatively, the inner container body 85 and the reactant vessel 86 can be made of two pieces that are sealed together. The container 80 further includes a breaking mechanism 90 provided at the bottom of the container 80. The breaking mechanism 90 includes a piston wiper 92 sealed to the inner wall of the outer container body 82. The principles of a piston wiper is well known to those skilled in the art. The piston wiper 92 includes a pair of longitudinally extending pins 94. When the piston wiper 92 is pushed and turned as

illustrated in Figure 9, the pair of pins 94 punctures and rips open the barrier 83 releasing the second reactant into the upper compartment of the first chamber 83. The second reactant mixes and reacts with the first reactant provided within the upper compartment of the first chamber 83.

[064] Referring to Figure 10, the container 100 includes an outer container body 102 defining a first chamber 103, an inner container body 104 defining a second chamber 105 disposed within the outer container body 102, and a reactant vessel 106. The reactant vessel

106 is provided within the first chamber 103 below the inner container body 104 and mounted on a push and turn piston wiper 107. The container 100 further includes a serrated blade cutter 108 molded to, the outer surface of the bottom of the inner container body 104. When the piston wiper 107 is pushed and turned as shown in Figure 11, the reactant vessel 106 is pushed toward the inner container body 102 and the barrier 109 comes in contact with the cutter 108 causing the cutter 108 to break the barrier 109.

[065] Referring to Figures 12A, 12B, and 12C, in one embodiment, the inner container body 120 has a breaking device 122 formed into the bottom surface. The structure of the breaking device 122 is substantially similar to the breaking device shown in Figures IF, IG, and IH.

[066] Referring to Figure 13, the container 130 includes an outer container body 132 defining a first chamber 133 and an inner container body 134 defining a second chamber 135 disposed within the outer container body 132. The container 130 further includes an insulating sleeve 136 provided along the inner surface of the outer container body 132 to enhance insulation of the container 130. The insulating sleeve 136 can be made out of an insulating material such as Styrofoam. The insulating sleeve 136 is useful in keeping the outer container body 132 from getting too hot and therefore uncomfortable for a consumer to hold and at the same time, direct as much of the heat to the inner container body 134 to heat

the substance as possible. The insulating sleeve 136 can be used with any of the containers described in Figures 1 through 12 above.

[067] In one embodiment, the containers described above are manufactured and assembled as follows. The reactant vessel can be separately manufactured using any conventional manufacturing method such as thermoforming or injection molding. In one embodiment, the reactant vessel is filled with the solid reactant such as calcium chloride, and covered with a foil sealed to the reactant vessel. This allows the manufacturer to check the seal of the reactant vessel prior to assembling the rest of the container. The outer container body and the inner container body are also separately manufactured using conventional manufacturing methods such as injection molding. The breaking device, which can also be made using injection molding or other methods, is secured to the inner container body. The pieces are assembled as follows. The outer container body is placed into a holder in a filling line. An adhesive is provided on the inner surface of the bottom of the outer container body where the reactant vessel will contact. The reactant vessel is placed inside the outer container body and secured to the bottom. Water is placed in the outer container body. The inner container body is dropped into the outer container body and the beverage or substance is placed inside. One advantage of having water in the outer container body and not the reactant vessel is that water naturally moves out of the way when the inner container body is dropped into the outer container body and therefore no additional step, such as a complex spinning step, is necessary to move the reactant out of the way. A pull tab lid is placed on top of the inner container body, rolled, and the inner container and the pull tab lid are crimped to the outer container body making a seal using a conventional method. The underside of the pull tab lid can be coated with any FDA approved coating to protect the beverage or food products from contacting raw aluminum. A snap-on drinking lid is placed on top of the outer container. Other appropriate manufacturing and assembling methods well known to those

skilled in the art may also be employed to manufacture and assemble the containers of the present invention.

[068] The containers described in Figures 1 through 13 above can be used not only for self-heating a substance but also for self-cooling a substance by substituting the reactants to those that are capable of generating an endothermic reaction when mixed.

[069] Other embodiments and uses of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. Although the invention has been particularly shown and described with reference to several preferred embodiments thereof, it will be understood by those skilled in the art that various changes in the form and details may be made therein without departing from the spirit and scope of the invention.