FOOD OR BEVERAGE CONTAINER HAVING HEAT EXCHANGE UNIT INTERNALLY THEREOF AND THERMOCHROMIC MATERIAL ON OUTER SURFACE TO INDICATE TEMPERATURE CHANGE

FIELD OF THE INVENTION

The present invention relates generally to a self-heating or self-cooling container having a heat exchange unit contained internally thereof and more specifically to such a container which has provided to the exterior surface thereof a thermochromic material which changes appearance as the food or beverage contained within the container changes its temperature as a result of activation of the heat exchange unit.

BACKGROUND OF THE INVENTION

Food or beverage containers which have a heat exchange unit contained therein which when activated chill the contents of the container are well known in the art. Such devices contain various types of refrigerants which may be chemical, electrical, include gaseous reactions and the like. Typical of such devices are those disclosed in U.S. Patent Nos. 2,460,765; 3,373,581; 3,636,726; 3,726,106; 4,584,848; 4,656,838; 4,784,678; 5,214,933; 5,285,812; 5,325,680; 5,331,817; 5,606,866; 5,692,381; 5,692,391; 6,102,108 and 6,125,649.

Such containers having a heat exchange unit in contact with food or beverage which when activated will heat the food or beverage are also well known in the prior art. Such devices are illustrated and described in U.S. Patent Nos. 5,626,022; 6,986,435; 7,878,188; and 8,383,179. In each of these devices the heat exchange unit when activated provides an exothermic reaction as a result of the intermixing of materials contained therein which releases a reaction heat.

Thermochromic materials are also well known in the prior art and are based principally on the utilization of liquid crystals and leuco dyes. The liquid crystals are often applied in layers through the utilization of carrier structures while the thermochromic dyes are based on mixtures of leuco dyes with suitable other chemicals and may also be utilized in the form of microcapsules with the mixture sealed inside. The material may also be in the form of paint or ink which may be directly applied to a desired surface. In either instance, it is known that these thermochromic materials when exposed to changes in temperature will provide general indicators of the temperature to which they are exposed by changes such as a change in color or going from opaque to transparent and in the case of the liquid crystals depending upon the material used may provide a very precise indication of the temperature to which it is exposed. A thermochromic material may be applied to the exterior surface of a food or beverage container and it is known in the prior art that such has been done. In the prior art situations where a thermochromic material has been applied to the exterior of a container having food or beverage therein, the container is subjected to cold by being placed in a refrigerator or a container having ice or the like and when the contents of the container reach a particular temperature, the thermochromic material will indicate that such has occurred. Similarly, when the contents of a container are subjected to heat, such as by applying it to a stove or in a container of water which is heated or the like, the thermochromic material will also indicate when the contents of the container have reached a particular temperature. Typical of such applications are the structures as disclosed in U.S. Patent 5,223,958 and U.S. Published Application 2002/0097777, both of which are directed to a heat activated structure, while U.S. Patents 6,979,120; 7,963,694; 5,202,677; 6,634,516; and 6,579,006 are directed to such containers that have a range of temperature change which could extend from very cold to very hot.

There has, however, been no food or beverage container which contains a heat exchange unit fixed thereto and extending into the container in contact with the food or beverage which when activated will directly cause the contents of the container to change temperature that has applied to the outer surface of the container a thermochromic material.

SUMMARY OF THE INVENTION

A container for food or beverage having an outer surface and a heat exchange unit secured internally thereof which when activated will chill or heat the food or beverage, means for activating the heat exchange unit to heat or chill the food or beverage and a thermochromic material deposited on the outer surface of the container and having a temperature range such that it changes appearance when the temperature of the food or beverage within the container reaches the temperature range of the thermochromic material as a result of activating the heat exchange unit.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of a container for food or beverage having a heat exchange unit contained internally thereof;

Figure 2 is a partial cross section drawing of a container such as that shown in Figure 1 but having a heat exchange unit therein for heating the food or beverage;

Figure 3 is a cross-sectional view of a container such as that shown in Figure 1 and having a heat exchange unit internally thereof adapted to chill the food or beverage contained within the container;

Figure 4 is a schematic representation of a thermochromic material applied utilizing a plurality of layers of the thermochromics material;

Figure 5 is a perspective view of a container of the type above described having a thermochromic material applied to the outer surface thereof wherein the food or beverage in the container is in a first temperature condition;

Figure 6 is a perspective view of the container of Figure 5 in a second temperature condition;

Figure 7 is a perspective view of the container of Figure 5 in a third temperature condition;

Figure 8 is a cross-sectional view of the thermochromic material on the external surface of the container shown in Figure 5 taken along the lines 8-8 of Figure 5;

Figure 9 is a cross-sectional view of the thermochromic material on the container as taken about the lines 9-9 as shown in Figure 6; and

Figure 10 is a cross-sectional view of the thermochromic material taken about the lines 10-10 of Figure 7; and

Figure 11 is a cross-sectional view of a container having a heat exchange unit charged with liquid carbon dioxide and having a valve providing a restricted orifice to allow the liquid phase carbon dioxide to pass directly to the gaseous phase.

DETAILED DESCRIPTION

Referring now more particularly to Figure 1 , there is disclosed in schematic format a container 10 for food or beverage constructed in accordance with the principles of the present invention. The assembly 10 includes an outer container 12 within which there may be housed food or beverage. A heat exchange unit 14 is secured to the container 12 through an opening provided in the bottom 24 of the container 12 and is secured by crimping as shown generally at 20 thereof. The heat exchange unit 14 has an exterior surface 18 which is in contact with the food or beverage which is contained within the outer container 12. A means 16 for activating the heat exchange unit 14 is secured to the top of the heat exchange unit 14 as illustrated. The heat exchange unit 14 may have contained internally thereof materials which upon activation of the heat exchange unit through the means 16 will either heat or chill the food or beverage contained within the outer container 12. The open end 19 of the container 12 may be closed by a cover which will have a removable portion enabling the consumer to gain access to the food or beverage contained within the outer container 12.

Referring now more particularly to Figure 2, there is illustrated in cross section a container 21 for housing food or beverage as above described and which includes a heat exchange unit 22 affixed to the top 28 of the container and extending internally into the interior of the container 21 in contact with the food or beverage contained therein. The heat exchange unit 22 has first and second compartments 23 and 29 separated by a permeable membrane 25. Reactant media is contained within sections 23 and 29 of the heat exchange unit 22 which when mixed together will generate an exothermic reaction. The reactant media may be water which would be contained within the region 23 and lime 30 in the region 29. Instead of the lime, a measured amount of calcium oxide may be utilized in the area 29 which when reacting with water will form calcium hydroxide again creating an exothermic reaction. Another alternative material which may be utilized for a reactant material is a magnesium-iron alloy which again when combined with the water will generate an exothermic reaction to produce heat. When it is desired to activate the heat exchange unit 22, the consumer may press down on the movable cap 31 so that the top 27 of a spear 32 will be pressed downwardly causing the tip of the spear 32 to break the permeable membrane 25 thereby releasing the water contained within the area 23 so that it reacts with the material 30 contained within the area 29. A flange 27A reacts with a closure 26 so that the amount of movement of the spear 30 is accurately controlled. The spear also contains fingers 27D which prevents upwardly removing the spear from the container. Once the exothermic reaction has taken place and the contents of the material within the container 21 has been appropriately heated, such will be indicated by a thermochromic material which is affixed to the outer surface of the container 21 as will be described more fully below and the consumer may then open the upper surface of the container by utilization of the pull tab 21 A to allow access to the material contained within the container 21 which in this case is illustrated as a beverage.

Referring now more particularly to Figure 3, there is illustrated at 100 a structure constructed in accordance with the principles of the present invention. As is therein shown, an outer container 112 has a food or beverage 114 contained internally thereof. The container 112 is closed at its top end 116 and may have a member that will allow the access to the food or beverage 114 by being removed as is well known to those skilled in the art. The outer container 112 has an outer surface 120 to which there is applied a thermochromic material as will be described more fully hereinbelow which will provide an indication as to the chilled temperature of the food or beverage 114 contained within the outer container 112. A heat exchange unit 121 extends internally of the outer container 112 into contact with the food or beverage 114. The heat exchange unit 121 is necked inwardly as shown at 132 and 134 so that the upper surface 122 thereof can be affixed to an opening provided in the bottom of the outer container 120 through crimping or other attaching mechanisms well known to those skilled in the art. An activating mechanism 124 is affixed to the upper end 122 of the heat exchange unit 121. The activating mechanism includes a push button 130 which will provide an opening through an extension 128 to permit the inward flow of carbon dioxide gas to be adsorbed by compacted carbon material 138 contained within the heat exchange unit 121. Alternatively, when it is desired to chill the food or beverage 114 contained with the container 112, the protective cap 150 can be removed and the button 130 depressed to allow the carbon dioxide gas adsorbed onto the compacted carbon particles to escape through the activating mechanism 124 to the atmosphere thereby cooling the food or beverage 114 contained within the outer container 112. Alternatively the heat exchange unit 121 may receive liquid carbon dioxide which upon activation of the button 130 will be allowed to escape through a restricted orifice adapted to require the carbon dioxide to pass from the liquid state directly to the gaseous state while chilling the food or beverage.

Referring now more particularly to Figure 11, there is illustrated in cross section a container having a structure defining a restricted orifice to allow liquid carbon dioxide to pass from the liquid state directly to the gaseous state. As illustrated in Figure 10, there is provided a fitting or attachment adapter 322 which is metal and preferably is aluminum and includes threads 323 formed thereon to be threadably received within the upper open portion of the HEU 318 which has complementary threads thereon. The attachment adapter may also be constructed of molded plastic material. The attachment adaptor 322 receives a plastic valve member 324 having first 317 and second 319 ends in an opening or a first bore 325 provided therethrough which functions as a valve sleeve and also receives a burst disc assembly 326 which is also threadably received within an opening or second bore 327 provided within the attachment adapter 322. The valve 324 and the bore 325 function as a typical spool and sleeve valve. The attachment adaptor 322 has a plastic overmolded base support ring 329 which is applied thereto in an overmolding process in which the plastic member is formed by injection molding of polypropylene into a mold into which the attachment adaptor 322 has been placed. The support ring 329 includes an outwardly extending flange having a top surface which seats against the bottom portion 316 of the beverage can 312 and the entire assembly of the attachment adaptor 322, valve 324 and burst disk assembly 326 is held in place by a base component 328. The base component 328 has a snap ring member 330 formed by a plurality of claws that snaps over a circumferential protrusion 332 on the upper portion of the attachment adaptor 322 and thereby secures the HEU with the valve assembly 320 and the burst disk assembly 326 onto the bottom of the beverage can 312. A plastic washer (not shown) may also be seated between the bottom of the can and the upper surface of the base support ring. A button component 334 is held in place in the base component 328 and, when moved downwardly, a protrusion 336 will engage the upper or second end 319 of the plastic valve member 324 and push it downwardly against the force of the valve spring 337 to provide a restricted orifice through which the liquid carbon dioxide contained within the HEU may enter the gaseous state directly and escape the HEU. The valve spring 337 is seated against a shoulder 339 formed by a reentrant bore 341 of the first bore 325 in the top or upper surface 343 of the attachment adaptor 322 and the lower surface of the plastic valve retainer 345 which is snap fitted to the top of the valve stem 321. The gaseous state C02 will pass along a restricted flow path between the exterior of the plastic valve 324 and the surface of the bore 325 provided in the attachment adaptor 322 so that the liquid C02 which now is passing from the liquid state directly to the gaseous state may flow upwardly around the outer surface of the plastic valve stem 321 to exit the attachment adaptor 322. There is, however, a gas deflector 338 which is positioned across the upper portion of the attachment adaptor 322 and operates such that when the carbon dioxide in the gaseous state flows upwardly through the opening around the valve stem 321 of the plastic valve 324, it will be deflected radially outwardly and it will then be caused to be deflected downwardly by the base component along the outer surface 340 of the beverage can 312.

The plastic valve 324 is molded with an outwardly extending lower portion 349 which has a continuous sharp edge 342 which engages the lower surface 344 of the attachment adaptor 322 to provide a very effective seal. The valve 324 is molded of a polymer material which has some flexibility. As a result, the sharp edge 342 of the valve 324 bends slightly outwardly against the surface 344 to more effectively create the seal. The forces exerted on the valve 324 by the valve spring 337 and the pressure of the liquid C02 in the HEU cause this bending. When the valve 324 is depressed downwardly by the protrusion 336, the section 346 has a first surface which is still within the bore 325 provided in the attachment adaptor 322 and functions to provide the pressure drop and the desired throttle to maintain the liquid carbon dioxide within the HEU in the boiling state so that it passes directly from the liquid to the gaseous state. This prevents the formation of dry ice and thus allows maximum cooling according to the enthalpy of vaporization. The section 346 of the valve 324 and the diameter of the bore 325 in the region where the section 346 resides are dimensioned to provide a gap between two and fourteen microns when the section 346 is perfectly concentric in the bore 325. If the section 346 is not perfectly concentric then the dimensions are such that a maximum gap of between four and 28 microns is provided. The gap extends for the entire length of the section 346 which in accordance with the presently preferred embodiment is 0.5 mm. This gap provides the critical restricted orifice which when activated allows the liquid carbon dioxide to pass directly from the liquid state to the gaseous state but at the same time maintains the pressure in the HEU such that all of the residual carbon dioxide remains in the liquid state.

Referring now more particularly to Figure 4, there is illustrated in schematic format one arrangement of thermochromic materials that may be applied to the outer surface of the outer containers containing the food or beverage as above described. As is illustrated in Figure 4, the thermochromic system may have a substrate layer 42 with thermochromic film layers 43 separated by noninvasive barrier layers 44. This stacked display has more than one layer and may have three or more layers depending upon the particular application. The generally planar displays are stacked with a barrier of a lower display providing the support for the thermochromic material of the next displays. The displays may exhibit that the thermochromic material changes appearance as the temperature of the food or beverage contained within the outer container changes depending upon the particular temperature range of the thermochromic material and whether the system is designed to heat the food or beverage contained within the container or to chill the food or beverage contained within the container. The substrate material may be any material which is desired and typically ils transparent and preferably the substrates are of a latex formulation well known to those skilled in the art and preferably are polyesters. Typically, the thermochromic material 43 is an ink which is applied to the substrate, preferably by silk screening or knife coating. After the thermochromic ink has been applied, it is allowed to dry to a film and the noninvasive barrier layer is applied, preferably painted on with a brush, knife, roller or spray gun. When the barrier layer has dried, the next layer of thermochromic ink responsive to a different range of temperature than the first layer of thermochromic ink is applied to the barrier layer of the first layer. The alternating applications of thermochromic inks and barriers are performed until the desired number of displays is achieved.

A food or beverage container in accordance with the present invention may take many forms depending upon the food or beverage and the amount thereof which is to be provided to a consumer. One embodiment of the invention is shown in Figures 5, 6 and 7 and in this embodiment of the invention a thermochromic material is shown applied to a beverage container 200. In this case the beverage container 200 is in the form of a pop top can of the type commonly employed for retaining beverages such as soda, beer and other liquids intended for human consumption. In this particular indication, the beverage container contains an energy drink which is commonly sold under the trademark WEST COAST CHILL. In Figure 5, the beverage container 200 and the thermochromic material 210 applied thereto is shown in a first temperature condition. Figure 6 shows the thermochromic material 210 and the beverage container 200 in a separate temperature condition and they are shown in a third temperature condition in Figure 7. Figures 8, 9 and 10 show the thermochromic material in the conditions shown in Figures 5, 6 and 7 and are taken about the lines 8-8, 9-9 and 10-10 in Figures 5, 6 and 7, respectively.

Although preferred temperature conditions can certainly vary depending on a number of factors including consumers' desires and the type of beverage contained, the preferred embodiment shown in Figures 5 through 10 provides in one useful example where a thermochromic material 210 has first, second and third image displays 210, 214 and 216 that overlies an image display region 211 of a substrate layer 213 (Figure 8). The substrate layer 213 could comprise a layer of sheet material that could be affixed to the sidewall 204 of the beverage container 200. For example, the substrate layer 213 could comprise a sheet of plastic material or other sheet material. An adhesive backing 215 may be applied to a surface thereof for affixing the layer of sheet material 213 to the beverage container 200. For example, the layer of thermochromic material could be similar to that shown in Figure 4 and above described. Alternatively, the substrate layer 213 could comprise the actual sidewall 204 of the beverage container 200 with the first image display 212 applied directly thereto.

The first image display 212 which in this case comprises a depiction of the trademark WEST COAST CHILL is a non-thermochromic material, for example, standard ink or the like. With this, the first image display 212 is not temperature dependent and therefore is always visible. The second image display 214 is in the shape of the word "COLD" is a thermochromic image. The second image display 214 is calibrated to become active or visible over an active temperature range that is well below room temperature and that is within a preferred range for consuming the beverage but not at a lower portion of that range.

For example, one can assume for the sake of the present discussion, that cold beverages are best served between 33° and 45° F (0.55°C and 7.2 °C). With this, the second image display 214 could be calibrated to have an active temperature range of 33° to 45° F. The third image display 216 which is in the shape of the word "ICE" has an active temperature range that overlaps with the active temperature range of the second image display 214 but is at a lower end thereof. For example, a third image display 216 could have an active temperature range of 33° to 40° F (0.55° C to 4.44° C). Under this arrangement then the first non-thermochromic image display 212 will always be visible. The first and second image displays 212 and 214 will be visible when the beverage and the thermochromic material 210 are cold, namely, below 45° F. and the first, second and third image displays 212, 214 and 216 will be visible when the beverage and the thermochromic material 210 are very cold, namely below 40° F. If desired, the image 216 could also have depictions of ice cubes, frost, icicles or similar items generating the impression of very cold to the consumer.

It should also be well understood by those skilled in the art that the energy beverage contained within the container 200 will have its temperature lowered only upon the activation of the heat exchange unit contained therein which is designed to lower the temperature of the beverage such as that displayed in Figure 3 and above described.

Of course one will further appreciate that the present invention is neither limited relative to the number of image displays nor limited to the breadth of the active temperature ranges. Accordingly, it will be clear that just one image display could be provided either to a single side of room temperature or to both sides of room temperature. It will be equally clear that a plurality of image displays with distinct or overlapping active temperature ranges could be provided on both sides of room temperature whereby a liquid could be indicated to be warm, hot or very hot or to be cool, cold or very cold. Further, one should be aware that the image displays 212, 214 and 216 and possibly others need not explicitly denote temperature. Instead, they could take the form of decorative displays that may or may not connote temperature conditions. By way of example, displays indicative of holidays, seasons, promotions, games, advertisements or the like could be provided.

It will be further recognized by those skilled in the art that the thermochromic material utilized may also show a particular color when the temperature range to which it is sensitive is reached. For example, when the energy drink WEST COAST CHILL reaches the range of 33° to 45° F., the image 214 could be shown in a light blue color and when the energy drink reaches the lower end of 33° to 40° F., the image 216 could be a very deep blue. Other colors could be utilized, for example, pink and red when the temperature range of the food or beverage within the container reaches the upper limits above room temperature assuming that the food or beverage contained within the container is to be consumed in a hot condition as opposed to cold as above described with regard to a WEST COAST CHILL energy drink.

There has thus been disclosed a food or beverage container having a heat exchange unit contained internally thereof which is adapted to have the exterior surface thereof in contact with the food or beverage contained within the container. A thermochromic material is applied to the exterior of the food or beverage container and when the heat exchange unit is activated to cause the temperature of the food or beverage to change, the thermochromic material applied to the exterior of the container will change its appearance as a result of the food or beverage reaching a predetermined temperature which is the sensitive temperature range for the thermochromic material applied to the exterior surface of the container.