Abstract:
Improved insulated containers and methods for production and storage are provided. The containers are composed of insulating material and can easily be constructed of a single sheet or a plurality of sheets of insulating material. The containers can be constructed of a flexible insulating material, and if placed inside an outer container, can conform to the contours of the interior surface of the outer container. The containers are thermally insulative and leak-proof, because of the continuous connections that result from the methods of forming the container. The methods of forming the containers also allow for multiple shapes and sizes to be constructed, allowing for placement inside many outer containers that also have varying shapes and sizes. The method of storing the container provides for space efficiency by rolling it into a cylinder.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to the field of insulation for packaging items.  
         BACKGROUND OF THE INVENTION  
         [0002]    The shipment or transport of perishable items frequently requires that such materials remain at a stable temperature, which is either raised or lowered with respect to ambient temperatures to which the packaging is exposed. Because of long transport times for perishable items and the sensitivity of certain of these items due to slight temperature fluctuations, considerable efforts have been made to provide shipping containers with improved insulating characteristics.  
           [0003]    Despite the somewhat satisfactory results of these devices, they have a number of drawbacks. While some of these systems provide arguably comparable insulating results, they frequently are cumbersome, costly, increase the weight of the overall package and decrease the volume of materials that can be transported in a given container. For example, U.S. Pat. No. 5,143,245 to Malone (1992) discloses a leak-proof insulating system for freight containers that requires a plurality of insulative strips for attaching the insulation system to the freight container, an expensive and time consuming procedure.  
           [0004]    A number of other known designs have attempted to utilize a bag constructed to nest inside a corresponding corrugated or other outer container. Such bag type constructions have generally not followed the contours of the outer container and have frequently had poor insulating characteristics. As a result, they are generally either too large or too small to be placed inside the outer container. If the bags are significantly smaller than the outer container that they are in, significant packing space is wasted. If the bags are too large, they often bunch up with unwanted excess material at each end, thereby wasting productive packing space and adding packaging weight, which ultimately increases shipping costs. For example, U.S. Pat. No. 5,820,268 to Becker et al. (1998) discloses an insulating bag with a gusseted pouch at either end of the bottom of the bag. Bags having this structure have had problems particularly when a liquid was inside of the bag in providing an adequate moisture-proof seal and preventing spillage. Damage to the outer container and/or the material inside the bags frequently resulted. Attempting to consistently vary the size of such bags to match their contents is again another costly and cumbersome experience. Furthermore, many prior art designs have been designed to perform optimally only when they are not fully loaded with perishable items.  
           [0005]    It is therefore apparent that there exists a need in the art for an improved packaging method and apparatus for perishable materials that provides a highly insulative packaging structure that is light weight, less costly for storage and shipping purposes, easily conforms to the shape of an outer shipping container, and has excellent thermal characteristics.  
         SUMMARY OF THE INVENTION  
         [0006]    The present invention provides an insulated container that is constructed of an insulating material, and includes a bottom with an outer perimeter, and a wall that extends above and is continuously connected to the outer perimeter of the bottom.  
           [0007]    The insulated container can be constructed of a single sheet of insulating material or a plurality of such sheets, depending upon the method used for construction. Regardless of the number of sheets used, when connecting the bottom to the wall, or when connecting various segments of the wall to each other, it is preferred that a seal be used. Depending upon the method of construction, the bottom of the insulated container may have numerous shapes, including, but not limited to: a circle, an ellipse, a rectangle, and a hexagon.  
           [0008]    The insulated container can also be constructed of a flexible insulating material, such as polyfoam or bubble sheeting, and can be removably inserted into an outer container having an internal surface with contours, such that the insulated container conforms to the contours of the internal surface of the outer container. It is preferred that the insulated container have a metalized surface on either the outer surface of the insulated container, or both the outer surface and the inner surface of the insulated container.  
           [0009]    The present invention also provides various methods for constructing the insulated container. One method involves removing segments from opposing ends of a rectangular sheet of insulating material, and then coupling the resultant flaps, preferably by a seal, so as to allow the formation of the wall and the bottom of the insulated container. Another method involves forming a fold within a fold, holding the double folds into place, preferably by a seal, unfolding the inner fold to form the wall and the bottom of the container, and then removing any excess flaps from the insulated container. A third method involves the formation of a cross-shaped piece of insulating material and then coupling the sides of the material together, preferably by a seal, to form the insulated container. A fourth method involves constructing the insulated container from at least two sheets of insulating material.  
           [0010]    The present invention further provides a method for storing the insulated container by rolling it into a cylinder having an outer surface, such that a portion of the external surface of the insulated container is on the outer surface of the cylinder. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0011]    [0011]FIG. 1A shows a cross-sectional view of the layers of a first material used to form the present invention.  
         [0012]    [0012]FIG. 1B shows a cross-sectional view of the layers of a second material used to form the present invention.  
         [0013]    [0013]FIG. 2A shows a perspective view of an embodiment of the present invention formed from a single sheet of insulating material.  
         [0014]    [0014]FIG. 2B shows a top view of the embodiment of the present invention shown in FIG. 2A.  
         [0015]    [0015]FIGS. 3A, 3B,  3 C, and  3 D show the steps of forming the embodiment of the present invention of FIGS. 2A and 2B.  
         [0016]    [0016]FIG. 4 shows a perspective view of an alternative embodiment of the present invention formed from a single sheet of insulating material.  
         [0017]    [0017]FIG. 5 shows a perspective view of a second alternative embodiment of the present invention formed from a single sheet of insulating material.  
         [0018]    [0018]FIGS. 6A, 6B,  6 C,  6 D, and  6 E show the steps of forming the embodiment of the present invention of FIG. 5.  
         [0019]    [0019]FIG. 7A shows a perspective view of a third alternative embodiment of the present invention formed from a single sheet of insulating material.  
         [0020]    [0020]FIG. 7B shows a top view of the third alternative embodiment of the present invention shown in FIG. 7A.  
         [0021]    [0021]FIGS. 8A, 8B, and  8 C show the steps of forming the embodiment of the present invention of FIGS. 7A and 7B.  
         [0022]    [0022]FIG. 9A shows a perspective view of an embodiment of the invention formed from a plurality of sheets of insulating material.  
         [0023]    [0023]FIG. 9B shows a top view of the embodiment of the invention shown in FIG. 9A.  
         [0024]    [0024]FIG. 10A, 10B,  10 C, and  10 D show the steps of forming the embodiment of the invention as shown in FIGS. 9A and 9B.  
         [0025]    [0025]FIG. 11 shows a side view of the storage of an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0026]    Referring to FIG. 1A and FIG. 1B, the insulated container of the present invention is constructed of a material having a brilliant surface, preferably a metalized polyethylene or metallic foil laminated on one or both of its sides. FIG. 1A illustrates a first preferred material that is a foil laminated bubble sheeting  1 . This material has a sidewall constructed of a thin foil laminate  2  such as metalized polyester or polyethylene. The foil laminate  2  is attached to a layer of polyethylene bubble sheeting  3  that has a plastic or polyethylene sidewall  4  opposite the foil laminate  2  and features a number of air pockets  5  within the material. Preferred results have been found when the foil laminate  2  is utilized on either the outer surface of the insulated container, or on both the external surface and the internal surface of the container. A variety of different thicknesses of laminated bubble sheeting  2  may be used depending upon the requirements of the product to be shipped in the container. It has been found that a laminated bubble sheeting having a thickness of {fraction (1/2)} inch to {fraction (3/16)} inch has been particularly effective.  
         [0027]    Referring now to FIG. 1B, an alternative insulating material for forming the insulated container is illustrated. This alternative material  6  consists of a thickness of polyethylene or polyurethane foam material  7  with a sheet of metalized polyethylene or metallic foil  8  laminated to one side of the foam material  7 . The material  6  is preferably used with the metalized polyethylene  8  on either the external surface of the insulated container, or both the external surface and the internal surface of the insulated container. Again, although a variety of thicknesses of polyethylene or polyurethane foam material  7  have been found effective and the given thickness will depend upon the desired properties for any particular shipment, beneficial results have been found with a foam material thickness of as little as {fraction (1/8)} to {fraction (1/4)} inch.  
         [0028]    In FIGS. 2A and 2B, the insulated container  10  of the present invention is constructed of a flexible insulating material  15 , and has a bottom  20  and a wall  30 . The bottom  20  has an outer perimeter  22 , which defines a boundary between the bottom  20  and the wall  30 . The outer perimeter  22  comprises two opposing creases  24  in the insulating material  15 , and two opposing horizontal seams  26  bonding the bottom  20  to the wall  30 . The wall  30  has two opposing vertical seams  32  beginning from the outer perimeter  22  of the bottom  20  and extending upward. The wall  30  does not have a defined shape, since the flexible insulating material  15  allows the wall  30  to have numerous shapes, and is merely circular in FIG. 2A for illustrative purposes.  
         [0029]    Referring to FIGS. 3A, 3B, and  3 C, the insulated container  10  is constructed of a single rectangular sheet  100  of flexible insulating material  15  as shown in FIG. 3A. The single rectangular sheet has a first side  110 , a second side  120  adjacent to the first side  110 , a third side  130  adjacent to the second side  120  and opposite the first side  110 , and a fourth side  140  adjacent to the third side  130  and the first side  110 , and opposite to the second side  120 . Two smaller rectangular pieces  150  of the single rectangular sheet  100  are then cut out by any known means, thereby forming an H-shaped configuration  160  as shown in FIG. 3B. The H-shaped configuration  160  contains a first flap  170 , having an outer end defined by the fourth side  140 , an upper end  171 , and an inner end  172 , a second flap  176 , having an outer end defined by the second side  120 , an upper end  177 , and an inner end  178 , a third flap  180  having an outer end defined by the fourth side  140 , an upper end  181 , and an inner end  182 , and a fourth flap  186  having an outer end defined by the second side  120 , an upper end  187 , and an inner end  188 . A first edge  175  separates the first flap  170  with the second flap  176  and a second edge  185  separates the third flap  180  with the fourth flap  186 . The first flap  170  and the second flap  176  are then folded towards each other so that the upper end  171  of the first flap  170  and the upper end  177  of the second flap  176  form a first connection  190  as shown in FIG. 3C. The first connection  190  causes the formation of a portion of the wall  192 . The portion of the wall  192  is then connected to the first edge  175  to form a portion of the outer perimeter of the bottom  191 . In order complete the formation of the insulated container  10 , the third flap  180  and the fourth flap  186  are then folded toward each other so that the upper end  181  of the third flap  180  and the upper end  187  of the fourth flap  186  form a second connection  193  as shown in FIG. 3D. The second connection  193  causes the completion of the wall  30  of the insulated container  10 . The wall  30  is then connected to the second edge  185  to complete the formation of the bottom  20  of the insulated container  10 . The first connection  190 , the second connection  193 , the first edge  175 , and the second edge  185  are then sealed to form a thermally protective and leak-proof barrier as shown by the two opposing horizontal seams  26  and the two opposing vertical seams  32  in FIG. 1B.  
         [0030]    Although the first edge  175  and the second edge  185  in FIG. 3B are straight, it is contemplated that a rectangular sheet of material may be cut to create a plurality of edges facing outward. More edges translate into a container having multiple shapes including, for example, a hexagon formed from three outward edges on each opposing side, or a twelve-sided bottom when each opposing edge has six sides. It is also contemplated that a rectangular sheet of insulating material may be cut to create an outward curved edge, such that an insulated container with a circular bottom is created or an insulated container  200  with an elliptical bottom  220  is created as shown in FIG. 4. As in the insulated container  10  of FIGS. 1A and 1B, the insulated container  200  has a bottom  220  with an outer perimeter  222 , a wall  230 , two opposing horizontal seams  226 , two opposing vertical seams  232 , and two opposing creases  224 .  
         [0031]    In FIG. 5, another embodiment of the invention is represented by the insulated container  300 . Here, the bottom  320  has an outer perimeter  322  that is entirely comprised of a i 5  crease  324 . The wall  330  is attached to the outer perimeter  322  of the bottom  320 . The wall  330  has two sets of two diagonal seams  326 , each set on opposing sides of the wall  330  and two opposing vertical seams  332  extending upward from an intersection  328  on the wall  330 . The diagonal seams  326  each begin at a corner  327  and extend diagonally to the intersection  328  on the wall  330 .  
         [0032]    The insulated container  300  is constructed of a single rectangular sheet  400  of flexible insulating material  415  as shown in FIG. 6A. The single rectangular sheet  400  has a first side  410 , a second side  420  adjacent to the first side  410 , a third side  430  adjacent to the second side  420  and opposite the first side  410 , and a fourth side  440  adjacent to the third side  430  and the first side  410 , and opposite to the second side  420 . The third side  430  is then folded towards the first side  410  along a mid-line  450  of the rectangular sheet  400  to form a first fold  460  such that the first side  410  is coupled to the third side  430  as shown in FIG. 6B. The midline  450  is then folded inward along two opposing sides of the first fold  460  to form a second fold  470  within the first fold  460  as shown in FIG. 6C. The second fold  470  within the first fold  460  is then fastened together, preferably by a seal, along the second side  420  and the fourth side  440  of the rectangular sheet  400  as shown in FIG. 6D. The second fold  470  is then unfolded thereby forming the bottom  320  of the insulated container  300 , the wall  330  of the insulated container  300 , two opposing inward flaps  340  partially attached to the inner surface  350  of the wall  330 , and two opposing outward flaps  360  attached to the outer surface  370  of the wall  330  as shown in FIG. 6E. The two opposing inward flaps  340  are then fastened, preferably by a seal, to the wall  330 , and the two opposing outward flaps  360  are removed from the wall  330 , by any known means, forming the insulated container  300  of FIG. 5.  
         [0033]    In FIGS. 7A and 7B, another embodiment of the present invention is represented by the insulated container  500 . Here, the bottom  520  has an outer perimeter  522  that is entirely comprised of a crease  524 . The wall  530  is attached to the outer perimeter  522  of the bottom  520  and has four vertical seams  532 , each seam extending from a corner  531  of the bottom  520  of the insulated container  500 .  
         [0034]    The insulated container  500  is constructed of a single rectangular sheet  600  of flexible insulating material  615  as shown in FIG. 8A. The single rectangular sheet  600  has a first corner  610 , a second corner  620 , a third corner  630 , and a fourth corner  640 . A rectangular portion  650  of the single rectangular sheet  600  is removed from each of the four corners  610 ,  620 ,  630 , and  640 , thereby forming a cross-shaped piece of insulating material  660  having a center  670  and four sets of two adjacent perpendicular sides  680  as shown in FIG. 8B. Each of the two adjacent, perpendicular sides  680  of the cross-shaped piece of insulating material  660  are then folded together as shown by the four sets of double arrows in FIG. 8C. The two adjacent, perpendicular sides  680  are fastened, preferably by a seal, thereby forming the wall  530  of the insulated container  500 , wherein the center  670  of the cross-shaped piece of insulating material  660  becomes the bottom  520  of the insulated container  500  as shown in FIGS. 7A and 7B.  
         [0035]    In FIGS. 9A and 9B, an embodiment of the present invention represented by the insulated container  700  is created by a plurality of insulating walls. Here, the bottom  720  has an outer perimeter  722  that is entirely comprised of a seam  724 . The wall  730  is attached to the outer perimeter  722  of the bottom  720  and has two vertical seams  732  each seam extending from two adjacent corners  731  of the bottom  720  of the insulated container  700 .  
         [0036]    As shown in FIG. 10A, the insulated container  700  is constructed of three pieces of rectangular insulating material: a first piece  800 , a second piece  810 , each piece having equal dimensions, and a third piece  820  of rectangular material having a side that is three times the length of one of the sides of the first piece  800  and the second piece  810 . The first piece  800  is then fastened to the third piece  820 , preferably by a seal, to form a T-shaped configuration  830  as shown in FIG. 10B, such that the length of two adjacent sides  805  to the attached side of the first piece  800  is equal to two unattached portions  825  of the attached side of the third piece  820 . Each of the two adjacent sides  805  of the first piece  800  is then attached to each of the two unattached portions  825  of the attached side of the third piece  820 , such that the first piece  800  forms the bottom  720  of the insulated container  700 , and the third piece  820  form a portion of the wall  730  as shown in FIG. 10C. The second piece  810  is then fastened to an unattached side of the first piece  800 , preferably by a seal, to form another T-shaped configuration  840  as shown in FIG. 10D, such that the length of two adjacent sides  815  of the attached side of the second piece  810  is equal to two unattached portions  828  of the third piece  820 . Each of the two adjacent sides  815  of the second piece  810  is then attached to each of the two unattached sides  828  of the third piece  820  as shown in FIG. 10E, such that the second piece  810  completes the formation of the wall  730  of the insulated container  700 .  
         [0037]    In FIG. 11, the insulated container  900 , which has an external surface  920  and an internal surface  930 , is stored as a cylinder  910 . The cylinder  910  is rolled in a manner so that a portion of the external surface  920  of the insulated container  900  forms an outer surface  925  of the cylinder  900 .  
         [0038]    It is also contemplated that the insulated container of the present invention will be closed if placed inside an outer container. Since the insulated container is contemplated to be composed of flexible insulating material, the means of closing the insulated container will depend upon the shape of the wall and the bottom of the insulated container, as well as the shape of the inner surface of the outer container. Any known means of closing the insulated container may be performed to complete the storage process.  
       EXAMPLES  
       [0039]    A series of tests were performed in order to analyze the performance of the present invention with other insulating containers under various conditions. Characteristics of the insulating containers that were tested include: 1) space efficiency and 2) insulative properties.  
         [0040]    Space Efficiency  
         [0041]    Referring to Table 1, two containers were compared for space efficiency. A one-inch thick piece of insulating material was used to construct the container of the present invention and the interior volume of the container, and when placed inside a 12-inch by 10-inch by 3-inch outer container, was 80 cubic inches. When a container constructed with identical material and having identical dimensions, but with a gusseted extension at either end of the container was placed into the same outer container, the interior volume of the container was reduced to 48 cubic inches. Using the container of the present invention increases the available interior volume by 66% because the gusseted extensions form a 3-ply layer at either end, displacing available space that can be used to store items for transport or shipment.  
                   TABLE 1                       TYPE OF   Available interior space in container when placed       CONTAINER   into a 12-inch by 10-inch by 3-inch outer container                   Present invention   80 cubic inches       Gusseted container   48 cubic inches                  
 
         [0042]    Insulative Properties  
         [0043]    In a first test, a container of the present invention was completely filled with water. The container remained leak-proof. A container having a gusseted extension at either end of the container was also filled completely with water. The gusseted extension detached within 30 minutes from the side of the container, forming a rectangular pouch, after which the water leaked out of the container.  
         [0044]    In a second test, the container of the present invention and the container having a gusseted extension at either end of the container were each filled with 30 pounds of fish, stored for 12 hours and moved regularly. After drying for a period of 24 hours, the container having the gusseted extensions produced a strong odor of fish, emanating directly from the gusseted ends, even after drying. After another 12 hours passed, the fish odor was even stronger. The pouches at either end of the gusseted extensions allowed liquids to enter, thereby reducing accessibility to the container for cleaning. The residue left in the pouches provided for bacterial growth as evidenced by the odor. The container of the present invention produced no such odor and was ready for reuse after the drying period.  
         [0045]    In a third test, thermal insulative properties of the present invention were compared to other containers by placing each container into a corrugated outer container. The first container was 6 sheets of expanded polystryene (foam EPS) lined to the corrugated outer container and the second container was a molded EPS container. A temperature of 35° F. was initiated inside each of the three containers with the aid of frozen refrigerant gel packs. As illustrated in Table 2, when comparing the present invention with the 6 sheets of foam EPS, the foam EPS maintained the temperature of 35° F. for 13 hours, while the present invention maintained the same temperature for a 45% longer period of time at 18 hours and 51 minutes. When comparing the present invention with the molded EPS containers, the molded EPS containers maintained the temperature of 35° F. for 14 hours, while the present invention maintained the same temperature for a 40% longer period of time at 19 hours and 36 minutes.  
                       TABLE 2                           Time of temperature   Time of temperature       TYPE OF   maintenance at 35° F.   maintenance at 35° F.       CONTAINER   (Comparison 1)   (Comparison 2)                   Present Invention   18 hours and 51 minutes   19 hours and 36 minutes       6 Sheets of Foam   13 hours   —       EPS       Molded EPS   —   14 hours                  
 
         [0046]    From these examples, it is clear that the present invention was demonstrated to produce more effective results in its use than other containers.  
         [0047]    Thus, while specific embodiments and applications of this invention have been shown and described, it would be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.