Abstract:
A lunch box capable of blast frozen preservation. The lunch box has two compartments, having two containers that are concentric with each other. The lunch box can withstand blast freezing and is microwave compatible keeping two separate food components separate from each other. The lunch box is space saving and easily portable. One side dish container fits within the other main dish container.

Description:
CLAIM OF PRIORITY  
       [0001]    This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from an application for  LUNCH BOX CAPABLE OF BLASTFROZEN PRESERVING  earlier filed in the Korean Intellectual Property Office on Aug. 23 2002 and Aug. 7, 2003 and assigned Serial Nos. 2002-25112 and 2003-25444 respectively, the contents of which are hereby incorporated by reference. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to a rigid lunch box capable of holding food in various separate compartments, the lunch box being able to withstand blast freezing and reheating while keeping the food within the various compartments from mixing during the blast freezing and the reheating.  
           [0004]    2. Description of the Related Art  
           [0005]    Due to the fast paced nature of our society, pre-prepared foods are becoming more and more common. Office workers and students alike often bring pre-prepared foods with them to eat at lunch. One of the major concerns of pre-prepared foods is the presence of harmful and unwanted bacteria in the foods. When foods are mass produced, the food is then chilled or frozen. The chilled or frozen food is bought by the consumer. At lunch time, the consumer heats the food and then eats the heated food.  
           [0006]    In order to reduce the bacteria count in foods, pre-prepared foods that are cooked are then blast frozen. Blast freezing reduces the time that the food is at a temperature that bacteria can multiply. Cooked foods are placed in a compartment where the air temperature is below freezing. The below freezing air is circulated within the compartment until the prepared food freezes. The circulation of the air within the compartment and maintaining the circulated air at a very low temperature results in the prepared food freezing quicker, and thus the food is at a temperature where bacteria can multiply for a much shorter period of time than other food preparation methods.  
           [0007]    Recently, such prepared foods that undergo blast freezing are first placed in packages before the blast freezing. Each package is generally one portion of the food. In addition, the consumer can then use the same package to reheat the foods using a microwave oven.  
           [0008]    However, a single entree is often made up of many foods. It is preferred that each component of the entrees are kept separate during the blast freezing and the reheating to achieve a better flavor and texture when eating. U.S. Pat. No. 5,741,534 to Chung describes a packaging for an entree where the different components of the entree are kept separate during the blast freezing and the reheating. After reheating, the user perforates a thin, flexible partition layer with a knife causing each separate food component to mix. By keeping each of the components of food (e.g., the rice and the gravy) separate until when consumed, the flavor and the texture of the food is maintained at a higher quality than if the food components were mixed prior to blast freezing or prior to reheating.  
           [0009]    However, the Chung patent is disadvantageous in that the packaging for the food is designed so that the food must be eaten from the packaging. Because of the flexible partition layer, it becomes almost impossible for the consumer to move each component of food to some other dish, like a bowl or another plate to so the consumer can eat off this other dish. Because the consumer is required to eat from the package in Chung, the packaging is big and bulky and is therefore not suitable for transport to school or work. Worse yet, the plastic partition layer is mixed up in the food, making it difficult for the consumer to 1) separate the food from the plastic partition layer, 2) to remove the plastic partition layer from the mixed food, 3) to mix the food given that the plastic partition layer is embedded within the food and 4) messy for the consumer to remove the partition layer coated with gravy and sauces.  
           [0010]    U.S. Pat. No. 4,233,325 to Slagan et al., illustrate in FIG. 8 a first container  20  with a second container  24  disposed within. Ice cream  22  is disposed between a bottom surface of first container  20  and a bottom surface  28  of second container  24 . Syrup  32  is disposed in second container  24 . Bottom surface  28  of second container  24  keeps syrup  32  separate from ice cream  22 . When heated in microwave oven  38  by device  42  from top to bottom, syrup  32  heats up and melts while ice cream  22  does not melt. This is because bottom surface  28  of second container  24  and the sidewalls of first container  20  do not allow microwave radiation to penetrate leaving ice cream  22  cold and frozen while syrup  32  melts. After microwave heating, the syrup  32  is poured over ice cream  22  as illustrated in FIGS. 9 and 10 of Slagan &#39;325  
           [0011]    However, the Slagan &#39;325 patent does not allow the bottom food to be heated. Much of the packaging of Slagan &#39;325 is resistant to microwave energy and thus does not allow ice cream  22  to heat up. Although this may be fine for ice cream, if another food was located where the ice cream  22  is in Slagan &#39;325, it would be desirable to also heat the food in the bottom compartment. Thus, it would be desirable to have all of the food packaging or lunch box to be made of a material that does not resist microwave energy.  
           [0012]    Therefore, what is needed is a packaging or a lunch box for food, where different components of the entree are kept separate from each other during the blast freezing process and the reheating process so that the consumer can place each food component in a separate dish to eat from after reheating. What is also needed is a food packaging where the partitions are rigid to enable the user to transfer the food to another dish. What is still needed is a packaging that can withstand blast freezing and reheating. What is also needed is a food packaging that has a shape that is easily portable by students and office workers so that the packaging or lunch box is compact. Further, what is needed is a food package that is easy for the consumer to remove the food from and later mix together that is not messy or difficult to handle or difficult to remove from the food or that prevents the consumer from mixing the two components easily. What is also needed is to heat the food in both compartments simultaneously.  
         SUMMARY OF THE INVENTION  
         [0013]    It is therefore an object of the present invention to provide an improved lunch box that can withstand blast freezing and reheating.  
           [0014]    It is also an object of the present invention to provide a lunch box that keeps separate food components physically separated from each other during blast freezing and reheating.  
           [0015]    It is further an object of the present invention to provide a lunch box that is rigid enough to allow the user to pour each of the food components into a separate dish after reheating so that the user does not have to eat from the food packaging.  
           [0016]    It is further an object of the present invention to provide a lunch box that is compact in shape thus enabling for easy travel to work or school.  
           [0017]    It is still an object of the present invention to provide a food lunch box where it is easy for the consumer to easily mix the food components together.  
           [0018]    It is yet an object of the present invention to provide a lunch box where the user can mix the food components together after heating without incurring a mess.  
           [0019]    It is still an object of the present invention to provide a lunch box where the packaging does obstruct the ability of the user to mix together and eat the two food components after heating and mixing.  
           [0020]    It is also an object of the present invention that the food in both compartments are heated simultaneously by using materials for the lunch box that do not resist microwave.  
           [0021]    These and other object can be achieved by a food package or lunch box made out of a relatively inflexible material that can withstand blast freezing and is microwave compatible where the material does not resist microwave energy and allows microwave radiation to pass through. The dimensions and shape of the lunch box is that the height, width and length of the lunch box are all close to being equal with each other thus making the lunch box easily portable. The lunch box has a main rice compartment and a second side dish compartment, the side dish compartment fits inside the main rice compartment to conserve space. Since the side dish compartment and the main rice compartment are made of a relatively thick and somewhat rigid material, the contents of both the main rice compartment and the side dish compartment can be emptied into another dish after re heating so that the user is not required to eat from the lunch box. 
       
    
    
     BRIEF DESCRIPTIONS OF THE DRAWINGS  
       [0022]    A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:  
         [0023]    [0023]FIG. 1 illustrates a perspective view illustrating a first embodiment of the present invention;  
         [0024]    [0024]FIG. 2 illustrates an exploded perspective view illustrating a first embodiment of the present invention;  
         [0025]    [0025]FIG. 3 illustrates a vertical sectional view illustrating a first embodiment of the present invention;  
         [0026]    [0026]FIG. 4 illustrates a perspective view illustrating a second embodiment of the present invention;  
         [0027]    [0027]FIG. 5 illustrates an exploded perspective view illustrating a second embodiment of the present invention;  
         [0028]    [0028]FIG. 6 illustrates a vertical sectional view illustrating the packing state according to a second embodiment of the present invention; and  
         [0029]    [0029]FIG. 7 illustrates a perspective view illustrating the packing state according to a second embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0030]    Turning to the figures, FIG. 1 illustrates an exterior of lunch box (or container or packaging)  100  according to the first embodiment of the present invention. Lunch box  100  has main outer container  10  which is covered by an extra cover  40 . Although main outer container  10  is illustrated as having a square cross section, it will be appreciated that main outer container  10  may also be of a circular or rectangular cross section. It is noted that the height of lunch box  100  is only slightly larger than either the width, the length, or the diameter of the lunch box, however, this invention is not limited to the exact dimensions of the lunch box  100  illustrated in FIG. 1. In the present invention, none of the height, the width, and the length or diameter is either much larger or much smaller than the other dimensions, resulting in a compact, efficient and easily portable design.  
         [0031]    [0031]FIG. 2 illustrates an exploded view of the lunch box  100  of FIG. 1 with all of the internal components not illustrated in FIG. 1. In FIG. 2, a side dish container  20  is illustrated. Side dish container  20  fits inside main outer container  10 . On the upper edge of the side dish container  20  is a rim  21  that hangs on a sloped indented portion  13  of the main outer container  10 . The side dish container  20  is designed so that the contents  102  of the side dish container  20  do not mix with the contents  101  of the main outer container  10 . The main outer container has a lip  11  on an upper edge. A sealed paper plate  30  is attached to lip  11  of main outer container  10 . Also, a top cover  40  attaches to lip  11  of main outer container  10 . Lip  11  has an edge protruding portion  12  at a distal end of lip  11  that locks with locking portion  41  on an inside part of rim  42  of extra cover  40 . Main outer container  10  and side dish container  20  are made of a material that is microwave compatible and that can tolerate blast freezing. Microwave compatible means that the lunch box can be put in a microwave oven and the microwave oven can heat the food within the lunch box without melting or destroying the containers of the lunch box.  
         [0032]    [0032]FIG. 3 illustrates lunch box  100  in use and also illustrates in detail the interrelationships of lip  11 , edge protruding portion  12 , extra cover  40  with locking portion  41 , rim  21  and sloped indented portion  13 . As illustrated, a first food  101  is disposed within main outer container  10  and below a bottom  24  of side dish container  20  and above a bottom  14  of main dish container  10 . A second food  102  is disposed in side dish container  20  on and above bottom surface  24  and the second food  102  does not mix with the first food  101 .  
         [0033]    As illustrated in FIG. 3, the length and width of side dish container  20  is slightly less than the length and width of main dish container  10  so that side dish container  20  fits within main dish container  10 . The rim  22  of side dish container  20  is supported by indented portion  13  of main dish container  10 , the indented portion  13  being near the top of main dish container  10  just below the lip  11 . In FIG. 3, the height of side dish container  20  is slightly less than half the height of main dish container  10 , however, in no way is the present invention limited by the exact height of side dish container  20  or by the exact proportion of the height of side dish container  20  compared to the height of main dish container  10 . First food  101  is disposed inside main dish container  10  beneath bottom surface  24  of side dish container  20  and on and above bottom surface  14  of main dish container  10 . Preferably, the first food  101  does not contact the bottom surface  24  of side dish container  20 . Second food  102  is disposed in side dish container  20  that is formed concentrically within main dish container. Second food  102  is disposed on and above bottom surface  24  of side dish container  20 . Bottom surface  24  of side dish container physically separates the first food  101  from the second food  102 . Bottom surface  24  of side dish container is made out of a material that is rigid and is not easily pierced with a knife. If a knife were to pierce bottom surface  24 , the second food  102  would not fall onto first food  101 , even if the second food  102  is runny like gravy or a sauce because of the rigidity of the material that makes up the bottom surface  24  of side dish container  20 .  
         [0034]    The first food  101  may be cooked rice and the second food  102  may be gravy, vegetables, meat, a sauce or any combination of these items. The second food  102  could also be a soup or a stew. Alternatively, second food  102  may be cooked rice and first food  101  may be gravy, vegetables, meat, a sauce or any combination of these items. It is, preferable to not mix the first food  101  with the second food  102  either prior to blast freezing or prior to reheating as the taste and texture of the food would otherwise be compromised. Further, it is noted that the design of lunch box  100  is so that the user is not required mix the first food  101  with the second food  102  within lunch box  100 . Also, it is not required that the user eat the food from lunch box  100 . Instead, it is preferable that the user, after heating first food  101  and second food  102  simultaneously, to place first food  101  and second food  102  in a separate dish (not illustrated) for eating. Therefore, first food  101  and second food  102  may be mixed in a separate dish separate from lunch box  100  after heating.  
         [0035]    It is also to be appreciated that the bottom surface  24  of side dish container  20  is not made of a material that is easily pierced by a knife. If this bottom surface  24  is pierced by a knife, little or none of second food  102  would fall onto first food  101  as the bottom surface  24  of the side dish container  20  is made of a rigid material.  
         [0036]    A process for using the lunch box  100  of the first embodiment of the present invention is as follows. The user brings lunch box  100  to work where the first food  101  and the second food  102  are frozen. The user then heats the lunch box  100  containing the first food  101  and the second food  102  preferably in a microwave oven. To do this, the user removes the extra cover  40  from the lunch box. Then the user grabs the handle part  31  of paper plate  30  and pulls open just a corner of the paper plate  30  to allow steam to escape. Then, the user places the lunch box  100  in a microwave oven and heats the food. When done, the user removes the side dish container  20  from the main dish container  10 . Then, the user places the first food  101  and the second food  102  in a plate (not illustrated) and the food is ready to eat. The user may, at this time choose to mix first food  101  with second food  102 . For example, if first food  101  is rice and second food  102  is chicken in a curry sauce, the user may first empty the first food  101  onto a plate and then empty second food  102  on top of first food  101  on the plate. This way, the first food  101  and the second food  102  are never in contact until immediately before eating, thus preserving food taste, quality and texture.  
         [0037]    [0037]FIGS. 4 through 7 illustrate a lunch box  110  according to the second embodiment of the present invention. The second embodiment is different from the first embodiment in that 1) extra cover  40  is replaced with paper cover  50  and plastic bag  60  and 2) the side dish container  20   a  contains a groove  22  used to allow steam from first food  101  to escape and to allow the user to easily grip side dish container  20   a  and easily remove side dish container  20   a  from main dish container  10 .  
         [0038]    Turning to FIG. 4, FIG. 4 illustrates an exploded view of the lunch box  110  of FIGS. 5 and 7 with all of the internal components not illustrated in FIGS. 5 and 7 according to the second embodiment of the present invention. In FIG. 4, a side dish container  20   a  is illustrated. Side dish container  20   a  is identical to side dish container  20  of the first embodiment except side dish container  20   a  has a steam ejection groove  22  formed in one corner extending from a bottom side  24   a  of the side dish container  20   a  to rim  21   a . This groove  22  serves two purposes. First, groove  22  allows steam from first food  101  to escape while being heated in the microwave oven. Secondly, groove  22  allows a user to easily separate and remove side dish container  20   a  from main dish container  10  after heating by insertion of a finger into groove  22 .  
         [0039]    Turning to FIG. 5, the handle part  31  of sealed paper plate  31  is disposed immediately above groove  22  of side dish container  20   a . Just before reheating, the user pulls handle  31  of paper plate  30  revealing groove  22  to allow steam to escape during heating. The user does not entirely remove the paper plate  30  prior to heating so that second food  102  will not dry out during heating.  
         [0040]    Turning to FIG. 6, FIG. 6 illustrates lunch box  110  filled with first food  101  and second food  102  according to the second embodiment of the present invention. FIG. 6 is similar to FIG. 3 except that paper cover  50  and plastic bag  60  are used instead of extra cover  40 . Paper cover  50 , for a square or rectangular cross sectional lunch box, has four side panels and a top and a bottom panel, with folds or creases between each adjacent side. Also side dish container has reference numeral  20   a  instead of  20  because of the presence of groove  22 . Paper cover  50  surrounds the entire lunch box  110 . Plastic bag  60  surrounds the paper covered lunch box  110 . Before heating in a microwave, the user completely removes plastic bag  60  and then tears a small hole in paper cover  50 . The user also peals back a corner  31  of sealed paper plate  30  exposing groove  22  of side dish container  20   a . The openings in paper cover  50  and paper plate  30  allow steam to escape during heating while keeping the food moist. The escaping steam prevents the lunch box  110  from building up a lot of pressure during heating eventually leading to an explosion.  
         [0041]    The above invention enables an entree of at least two food components to be stored in a compact container that can be used in blast freezing and microwave heating. Side dish container fits within and is essentially concentrically disposed within main dish container keeping both food components separate during blast freezing and reheating. After reheating, the user then empties the contents of both the main container and the side dish container into a separate plate or bowl for eating. Thus, the user may mix the first and second foods together in a separate dish after heating. The side dish container fits within the main dish container providing a compact lunch box that is easily portable.  
         [0042]    While this invention has been particularly illustrated and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details maybe made therein without departing from the spirit and scope of the invention as defined by the appended claims. The preferred embodiments should be considered in descriptive sense only and not for purposes of limitation. Therefore, the scope of the invention is defined by the appended claims.