Abstract:
A container is provided which includes body having a top portion and a bottom portion. Each of the top portion and bottom portion have lips which are affixed together at a first location. A perforation line is made in at least one of the top and bottom lips. The perforation line is between the first location and the container body. An adhesive member covers a portion of the perforation line between the top and bottom lip so that the adhesive member may be pulled through the perforation line to gain access inside the container body.

Description:
FIELD OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to an improved container. More particularly, the present invention relates to a tamper-evident seal for a container which is easily opened. 
         [0003]    2. Background of the Invention 
         [0004]    Plastic containers for distributing food and consumer goods are in common use. Such containers, when used for food, extend the shelf life of perishable products, resulting in savings to the food industry and fresher food to the consumer. One concern of consumers is the integrity of the food within the container. Consumers want to be assured that the food has not been tampered with prior to purchasing. It is desirable to provide such containers with a seal and a means to easily identify when those containers have been opened. Tamper evident seals for plastic containers are known in the art. Various prior art systems are available to provide evidence that a container has not been opened. One prior art method is to wrap the container with a plastic band which must be cut to gain access to the container. Other, more sophisticated methods are also known. For example, two such methods are shown in United States published patent applications 2005/0184070 A1 and 2007/0045317 A1, the disclosures of which are incorporated herein by reference. Containers for non-food consumer products also may require tamper-evident seals so that consumers can be assured that they are receiving new products in factory condition. 
         [0005]    A tamper-evident seal is needed which is easy to open, inexpensive to produce and which provides ready evidence that the seal has been broken. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention can be used in connection with a variety of plastic food and consumer product containers. The plastic used could be thermoplastic material such as polyethylene terephthalate (PETE), polystyrene, polypropylene and polyethylene, or other similar plastic material. The material may be, for example, from 0.010 to 0.050 inches thick. Such containers are typically made by thermoforming in a mold. The container could be of various sizes and configurations depending on the purpose of the container. The container could be used for food, such as baked goods, fruit, vegetables, meat, cheese, salads, eggs and other food items. The container could also be used for retail products such as batteries, compact disks, razors, electronics, hardware, tools and other products. 
         [0007]    In one embodiment, the invention employs a single-piece thermoformed container consisting of a bottom portion and a top portion joined by a hinge. In another embodiment, the container includes separate top and bottom portions which may be attached to one another. Preferably, the top and bottom portions are attached to one another near the edges through ultrasonic welding, heat staking, stitch welding or similar methods. If the top and bottom portions are joined by a hinge, then the welding can be on the side of the container opposite the hinge. If the top and bottom are separate, two or more sides can be attached to one another by ultrasonic welding, heat staking, stitch welding or similar methods. 
         [0008]    In either case, the top and bottom portions each have at least one lip extending out from the container body. A series of portions of weakened material or aligned cuts, such as perforations are disposed in one of the top or bottom lip portions. The lip can have one or two perforation lines. The perforations can be made with a steel rule die. In one example die, the teeth are spaced at 30 teeth per inch. The perforations are between the weld line and the body of the container on at least one side of the container. The perforation line is covered with an adhesive member such as tape, preferably, polypropylene or PETE tape, with, for example, an aqueous based acrylic or rubber based adhesive. One suitable tape is filament reinforced tape such as Scotch Tear Tape sold by 3M Corporation of St. Paul, Minn. The adhesive member is placed between the top and bottom lips and a portion of the adhesive member projects out from between the lips. 
         [0009]    To gain access to the container body, the adhesive member is pulled through the perforation line, breaking the perforations. The portions of the lips which are affixed to one another remain affixed, but the container may be opened because the perforation line is between the part of the lip which is affixed to the other lip and the container body. When the perforation line is broken it is evident that the container has been opened. 
         [0010]    The top portion and bottom portion can each have second lips which extend from the container body. These second lips can also be joined by welding or other similar methods and can include one or two perforation lines covered by an adhesive member, in the manner as described above. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Embodiments and applications of the invention are illustrated by the attached non-limiting drawings. The attached drawings are for purposes of illustrating the concepts of the invention and may not be to scale. 
           [0012]      FIG. 1  is a side elevation view of a container according to one embodiment of the present invention; 
           [0013]      FIG. 2  is a bottom plan view of the container of  FIG. 1 ; 
           [0014]      FIG. 3  is a top plan view of the container of  FIG. 1 ; 
           [0015]      FIG. 4  is an isometric view of the container of  FIG. 1  after closing and sealing the container; 
           [0016]      FIG. 5  is a cross-sectional view of the container of  FIG. 4  taken along line  5 - 5  in  FIG. 4 ; 
           [0017]      FIG. 6  is a cross-sectional view of the container of  FIG. 4  taken along line  6 - 6  in  FIG. 4 ; 
           [0018]      FIG. 7  is perspective view of another embodiment of the present invention; 
           [0019]      FIG. 8  is a top plan view of the invention of  FIG. 7 ; 
           [0020]      FIG. 9  is a perspective view of another embodiment of the present invention showing the top portion separated from the bottom portion; 
           [0021]      FIG. 10  is a perspective view of a portion of the top portion of the invention of  FIG. 9 ; 
           [0022]      FIG. 11  is a perspective view of a portion of the bottom portion of the invention of  FIG. 9 ; and 
           [0023]      FIG. 12  is a top plan view of the invention of  FIG. 9  in the closed position. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0024]    Throughout the following description specific details are presented to provide a more thorough understanding to persons skilled in the art. However, well-known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense. 
         [0025]    Preferred embodiments of the present invention are described with reference to  FIGS. 1-12 .  FIG. 1  shows one particular shape for a container  10 , it being understood that the container  10  is shown in this shape for illustration purposes only and that the container could take on a wide variety of shapes, sizes and configurations.  FIG. 1  shows the container  10  in an open orientation having a top portion  12  and a bottom portion  14 . The top portion  12  has a lip  20  extending away from the container top body  16 . The bottom portion  14  also has a lip  22  extending from the container bottom body  18 . The top portion  12  can have reinforcing ribs  24  and the bottom portion  14  can also have reinforcing ribs  26 . A hinge  27  is provided between the container top body  16  and the container bottom body  18 . 
         [0026]    As shown in  FIG. 6 , the bottom portion  14  has an upwardly extending wall  28  and the top portion  12  has a sidewall portion  30 . When the container is closed, the upwardly extending wall  28  presses against the sidewall portion  30  to hold the container closed. Other configurations for interlocking parts are commonly used and will be readily apparent to those skilled in the art. 
         [0027]    Reference is now made to  FIGS. 2 and 3 . It will be understood that while certain features are described in association with the lip  20 , this is done for illustration purposes, and that those features could be associated with lip  22  instead. In  FIGS. 2 and 3 , the lip  20  on the top portion  12  includes a perforation line  34  extending lengthwise along the lip  20 . The perforation line  34  consists of a series of aligned cuts or weakened portions of the lip  20 . In one example embodiment, the cuts or weakened portions may be between 20 to 40 per inch, separated by, for example, material which is 0.012 inches long, although various other dimensions of perforations will work. Although shown as straight, the perforation line may have other geometries. The perforation line  34  is covered with an adhesive strip  36 . Preferably, the lip  20  terminates at both ends in tabs  40  and  42 , which are removably attached to the lip  20 . Adhesive strip  36  extends, preferably, to both tabs  40  and  42 . Adhesive strip  36  is preferably constructed of filament reinforced tape, but other adhesive members can be used. 
         [0028]      FIG. 4  shows the container  10  in the closed configuration. The lips  20  and  22  have been affixed together by a know technique such as ultrasonic welding, heat staking or other techniques. For illustration purposes, the lips  20  and  22  are shown as welded together by welds  50 . The welds may be in the range of 0.06 inches to 0.1 inches in diameter. The welds may be separated from one another by spaces of 0.12 inches to 0.19 inches, for example. Other dimensions for the size of the welds and the spacing between the welds will work. When closed, the container  10  has adhesive strip  36  between lips  20  and  22 . 
         [0029]    The perforation line  34  must be broken to access the contents of the container  10 . The perforation line  34  can be broken by grasping tab  40  or  42  and pulling adhesive strip  36  through the perforation line  34 .  FIG. 4  shows tab  40  separated from the lip  20  and pulled partially through perforation line  34 .  FIG. 5  illustrates the partial opening of container  10  as well. Because the perforation line  34  is between the welds  50  and the container top body  16 , a portion of the lip  20  will remain attached to the lip  22  as the perforation line  34  is broken. Once the perforation line  34  is broken, the container  10  can be opened. 
         [0030]    As shown in  FIG. 7 , instead of being joined by a hinge, the top portion  112  and bottom portion  114  of container  110  could alternatively comprise two separate pieces. The top portion  112  has a lip  120  extending away from the container top body  116 . The bottom portion  114  also has a lip  122  extending from the container bottom body  118 . The top portion  112  can have reinforcing formations  124  and the bottom portion  114  can also have reinforcing formations  126 . A hinge  127  is created by providing a perforation line  129  on the lip  160  inside of weld line  131 , although other hinge mechanisms are possible. 
         [0031]    As shown in  FIG. 8 , the lip  120  on the top portion  112  includes two perforation lines  134  and  135  extending lengthwise along the lip  120 . The perforation lines  134  and  135  consist of a series of aligned cuts or weakened portions of the lip  120 . The perforation lines  134  and  135  are shown as straight, but may have other geometries. The perforation lines  134  and  135  are covered with an adhesive strip  136 . Preferably, the lip  120  terminates at both ends in tabs  140  and  142 , which are removably attached to the lip  120 . Adhesive strip  136  extends, preferably, to both tabs  140  and  142 . Adhesive strip  136  is preferably constructed of filament reinforced tape, but other adhesive members can be used. 
         [0032]    As shown in  FIGS. 7 and 8 , the lips  120  and  122  have been affixed together by ultrasonic welding, heat staking or other techniques. Ultrasonic welds  150  are shown as an example method of affixing the lips together. When closed, the container  110  has adhesive strip  136  between lips  120  and  122 . Lips  160  and  162  have also been affixed together by, for example, ultrasonic welds  151 . 
         [0033]    As with the embodiment shown in  FIG. 4 , the perforation lines  134  and  135  must be broken to access the contents of the container  110 . The perforation lines  134  and  135  can be broken by grasping tab  140  or  142  and pulling adhesive strip  136  through the perforation lines  134  and  135 . 
         [0034]      FIGS. 9-12  show another example embodiment. As shown in  FIGS. 9 and 12 , the top portion  212  and bottom portion  214  of container  210  could comprise two separate pieces. The top portion  212  has a lip  220  extending away from the container top body  216 . As best seen in  FIG. 11 , the bottom portion  214  also has a lip  222  extending from the container bottom body  218 . The top portion  212  can have reinforcing formations  224  and the bottom portion  214  can also have reinforcing formations  226 . The top portion  212  has a lip  260 . The bottom portion has a lip  262 . 
         [0035]    As shown in  FIGS. 9 and 10 , the lip  220  on the top portion  212  includes two perforation lines  234  and  235  extending lengthwise along the lip  220 . The perforation lines  234  and  235  consist of a series of aligned cuts or weakened portions of the lip  220 . It is not necessary that the perforation lines  234  and  235  be straight. The perforation lines  234  and  235  are covered with an adhesive strip  236 . Preferably, the lip  220  terminates at both ends in tabs  240  and  242 , which are removably attached to the lip  220 . Adhesive strip  236  extends, preferably, to both tabs  240  and  242 . Adhesive strip  236  is preferably constructed of filament reinforced tape, but other adhesive members can be used. 
         [0036]    The lips  220  and  222  have been affixed together by ultrasonic welding, heat staking or other techniques. Ultrasonic welds  250  are shown for as an example method of affixing the lips together. When closed, the container  210  has adhesive strip  236  between lips  220  and  222 . As shown in  FIG. 12 , lips  260  and  262  have also been affixed together by, for example, ultrasonic welds  251 . Lip  260  also has two perforation lines  264  and  265 . The perforation lines  264  and  265  are covered with an adhesive strip  270 . The lip  260  terminates at tabs  266  and  268 . 
         [0037]    All perforation lines  234 ,  235 ,  264  and  265  must be broken to access the contents of the container  210 . The perforation lines  234  and  235  can be broken by grasping one of the tabs  240  and  242  and pulling adhesive strip  236  through the perforation lines  234  and  235 . Similarly, the perforation lines  264  and  265  can be broken by pulling on tabs  266  or  268  to pull adhesive strip  270  through the perforation lines  264  and  265 . 
         [0038]    It is to be understood that the exemplary embodiments are merely illustrative of the present invention and that many variations of the above-described embodiments can be devised by one skilled in the art without departing from the scope of the invention. It is therefore intended that all such variations be included within the scope of the following claims and their equivalent.