Abstract:
Polymeric containers that have a container body and a removable and replaceable lid configured for sealing engagement with the body. The sealing arrangement between the container body and the lids includes a discontinuity feature that provides a passage for fluid from the exterior of the container to the sealing arrangement, which reduces the forces needed to open (e.g., unseal) or vent the container. The containers are often thermoformed, and might be considered “disposable” containers.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/823,341, filed Aug. 23, 2006, entitled “Containers with Discontinuous Seal, and Methods”, which application is hereby incorporated by reference in its entirety. 
     
     TECHNICAL FIELD 
       [0002]    This disclosure generally relates to polymeric packages or containers, and, in particular, to rigid polymeric containers having a container body and a removable lid, the lid and container configured to cooperatively close but with at least one discontinuous seal region present around the engageable body and lid. 
       BACKGROUND 
       [0003]    Enhancing the sealing and opening capabilities of rigid containers, both disposable containers intended for one-time use and those intended for repeated use, is an area of ongoing development. 
       SUMMARY OF THE DISCLOSURE 
       [0004]    The present disclosure is directed to generally rigid, polymeric containers that have a body and a removable and replaceable lid configured for engagement with the body. The containers are often thermoformed, and are typically considered “disposable” containers, in that they may be discarded after one use, or a limited number of uses, generally dictated by the strength, integrity, and/or quality of the polymeric materials used to form the container. 
         [0005]    The present disclosure is directed to a container design that reduces the forces needed to open (e.g., unseal) or vent a container. The designs of this disclosure facilitate the removal of the lid from the container body. The configuration, in some embodiments, also functions as a drain passage, for example, to assist in water drainage from the container body after washing. 
         [0006]    The container includes a discontinuity feature in the sealing arrangement between the container body and the lid that provides a passage for fluid from the exterior of the container to the sealing arrangement. In some embodiments, the discontinuity feature, instead, provides a passage for fluid from the interior of the container to the sealing arrangement. In either case, the discontinuity features facilitates separating the container body and the lid when opening the container. The discontinuity feature may be present in one or both of the container body or the lid. In some embodiments, multiple discontinuity features are present in the container, and, in some of these embodiments, the features are distributed in more than one area of the container. In addition to the sealing arrangement including its discontinuity feature, the container can also include, for example along a different surface of the sealing arrangement, a leak-proof seal. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a top view of a rigid container, in this figure a rectangular container, having a container body and a lid, according to the present disclosure; 
           [0008]      FIG. 2A  is a cross-sectional side view of the rigid container of  FIG. 1  taken along line  2 A- 2 A of  FIG. 1 ; 
           [0009]      FIG. 2B  is an enlarged view of a portion of the rigid container of  FIG. 2A , detailing the sealing arrangement; 
           [0010]      FIG. 3A  is a cross-sectional side view of the rigid container of  FIG. 1  taken along line  3 A- 3 A of  FIG. 1 ; 
           [0011]      FIG. 3B  is an enlarged view of a portion of the rigid container of  FIG. 3A , detailing the sealing arrangement; 
           [0012]      FIG. 4  is a top view of a second embodiment of a rigid container, in this figure a square container, according to the present disclosure; 
           [0013]      FIG. 5  is a top view of a third embodiment of a rigid container, in this figure a rectangular container, according to the present disclosure; 
           [0014]      FIG. 6  is a top view of a fourth embodiment of a rigid container, in this embodiment a circular container, according to the present disclosure; 
           [0015]      FIG. 7  is a top view of a sixth embodiment of a rigid container according to the present disclosure; 
           [0016]      FIG. 8A  is a cross-sectional side view of the lid of the rigid container of  FIG. 7  taken along line  8 A- 8 A of  FIG. 7 ; 
           [0017]      FIG. 8B  is an enlarged view of a portion of the lid of  FIG. 8A ; and 
           [0018]      FIG. 9  is a top perspective view of an embodiment of a rigid container body according to the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Many existing rigid containers are designed to inhibit and, in same cases, prevent leakage from the interior volume of the container during storage and use of the container. In many instances, the objective is to create a high strength sealing arrangement between the container body and the lid that is sufficiently secure to inhibit and/or prevent seepage of fluids, including liquids, from the interior of the container. One of the results of high strength seal designs is that the closed sealed container can be difficult to open. As container designs have progressed to stronger and tighter seals, the lids have become more difficult to remove from the container body. Not having access to the product inside the container can be as frustrating, if not more frustrating, than having a liquid leak out from the container. A strong seal can be generally undesirable to users that have weak hand strength or limited range of motion. 
         [0020]    The containers of the present disclosure include a discontinuity in the sealing arrangement between the container body and the lid, the discontinuity allowing the flow of fluid (e.g., air) from the exterior of the container to the sealing arrangement, to interrupt the sealing contact of the container body and the lid surfaces and to facilitate removal of the lid from the container body. 
         [0021]    Referring to the figures, a rigid container is illustrated in  FIG. 1 ,  FIGS. 2A and 2B , and  FIGS. 3A and 3B . Container  10  includes a container body  20  and a lid  30  that is removable and replaceable onto body  20 . Container body  20  includes an interior volume  21  for receiving and storing items therein. Lid  30  inhibits access to interior volume  21 . 
         [0022]    Lid  30  attaches on to container body  20  via sealing arrangement  25 , generally located proximate a periphery  28  of container body  20  and a periphery  38  of lid  30 . Sealing arrangement  25  securably retains lid  30  onto body  20 . Sealing arrangement  25 , preferably, forms along and between lid  30  and body  20  and secures lid  30  and container body  20  so as to inhibit passage of fluid from interior volume  21  to the exterior of container  10 . Lid  30  includes a tab  35  that provides a grasping surface to facilitate removal of lid  30  from container body  20 . In accordance with this disclosure, sealing arrangement  25  includes a discontinuity in at least one position along the length of sealing arrangement  25  around periphery  28 ,  38 , that also facilitates removal of lid  30  from container body  20 . 
         [0023]    Each of container body  20  and lid  30  includes surfaces that can cooperatively form sealing regions of sealing arrangement  25 . These surfaces are configured to engage (e.g., frictionally) with each other. In the specific embodiment illustrated, these surfaces of container body  20  include an inner side wall  22 , a top wall  24 , and an outer side wall  26 , with outer wall  26  being closest to periphery  28 . Lid  30  includes corresponding cooperating surfaces, i.e., an inner side wall  32 , a top wall  34 , and an outer side wall  36 , with outer wall  36  being closest to periphery  38 . Container body  20  and lid  30  can be manufactured so that one or more of the paired cooperating surfaces inhibit fluid movement as part of sealing arrangement  25 . That is, sealing arrangement  25  has at least one pair of walls with sealing regions in contact, preferably in frictional contact (e.g., inner walls  22 ,  32 , top walls  24 ,  34 , or outer walls  26 ,  36 ). In many embodiments, walls  22 ,  24 ,  26  of container body  20  may be referred to as a lip, and walls  32 ,  34 ,  36  of lid  30  may be referred to as a groove. It will be appreciated that the sealing regions may extend along a portion or the entire length of paired body and lid walls. 
         [0024]    Referring to  FIGS. 2A and 2B , a portion of container  10  is illustrated where sealing arrangement  25  has three wall pairs with sealing regions, that is, inner walls  22 ,  32 , top walls  24 ,  34 , and outer walls  26 ,  36 , having sealing regions in frictional contact. In accordance with this disclosure, however, sealing arrangement  25  is configured or constructed with a discontinuity in one or both walls of a sealing region to intentionally interrupt the engagement between cooperating surfaces of container body  20  and lid  30 . 
         [0025]    Container  10  includes at least one discontinuity feature  50 , e.g., an indentation, divot, groove, bump, etc., within sealing arrangement  25  that forms a discontinuity within sealing arrangement  25 . That is, feature  50  breaks the continuous nature of sealing arrangement  25  in the sealing region between cooperating surfaces, inner walls  22 ,  32 , top walls  24 ,  34 , and/or outer walls  26 ,  36 , of container body  20  and lid  30  extending around container  10 . In the embodiment illustrated in  FIG. 1 , discontinuity feature  50  is present within container body  20  within the sealing region formed by walls  26 ,  36 . In particular, discontinuity feature  50  is an indent  52  present in outer wall  26  of container body  20 . 
         [0026]    In this embodiment of  FIG. 1 , three indents  52  are present in a corner of container body  20  and three additional indents  52  are present in an opposite corner of container body  20 . That is, the two sets of three indents  52  are positioned generally 180° apart. It should be understood that for a rectangular container, such as container  10  of  FIG. 1 , because lid  30  could be positioned in two different orientations, the discontinuity features are preferably present at two opposite corners. In this embodiment, indents  52  are present proximate lid removal tab  35 , when lid  30  is engaged with container body  20 . As shown, discontinuity feature  50 , such as indent  52 , can be formed in a corner of sealing arrangement  25  that is defined by a radius, so that no matter how lid  30  is oriented, the benefits of discontinuity feature  50  are realized. 
         [0027]    Various alternate configurations for placement of discontinuity feature(s)  50  are provided.  FIG. 4  illustrates a square container, container  110 , having a series of discontinuity features  50  in the sealing arrangement in each of the four corners. With such an arrangement, having four discontinuity features  50  positioned 90° apart, discontinuity feature  50  will facilitate removal of the lid from the container no matter on which corner the removal tab is located. 
         [0028]      FIG. 5  illustrates an alternate placement of discontinuity features  50  in a rectangular container. A series of discontinuity features  50  could additionally or alternately be located in non-radiused portions, e.g., to either side of the corners, as shown on container  120 . Such a configuration would be advantageous if the removal tab on the lid were located in a position other than at a corner. 
         [0029]    Yet another alternate embodiment is shown in  FIG. 6 , as circular container  130 , having discontinuity features  50  positioned e.g., generally evenly, around the sealing arrangement of the container, so that no matter where the lid removal tab is seated, the benefits of having the discontinuous seal are realized. In each of the embodiments of  FIGS. 4 through 6 , discontinuity feature  50  is present in a wall of the container body and breaks the continuous nature of the sealing arrangement in the sealing region between cooperating surfaces of the container body and the corresponding lid. 
         [0030]    Referring to  FIG. 7  and  FIGS. 8A and 8B , another alternate rigid container having a discontinuous sealing arrangement is illustrated as container  150 . Container  150  includes a container body  152  (illustrated only in  FIG. 7  in a top view) and a lid  153  that is removable and replaceable onto the container body. 
         [0031]    Lid  153  attaches on to the container body via sealing arrangement  125  proximate lid periphery  138 , which securably retains lid  153  onto body  152 . Sealing arrangement  125 , preferably, forms along and between lid  153  and container body  152  so as to inhibit passage of fluid from the interior volume to the exterior of container  150 . In accordance with this disclosure, sealing arrangement  125  includes a discontinuity in at least one position around along the length of sealing arrangement  125 . 
         [0032]    Each of container body  152  and lid  153  includes surfaces that can cooperatively form sealing regions of sealing arrangement  125 , these surfaces being configured to engage (e.g., frictionally) with each other. In this embodiment, various surfaces of sealing arrangement  125  include ‘cut back’ or ‘negative angle’ walls to increase the engagement of lid  153  with container body  152 . For lid  153 ,  FIG. 8B , the surfaces that engage with cooperating surfaces on container body  152  includes inner side wall  132 , top wall  134 , and outer side wall  136 . As in other embodiments, cooperating paired surfaces of body  152  and lid  153  have sealing regions that inhibit fluid movement as part of sealing arrangement  125 . In accordance with this disclosure, sealing arrangement  125  is configured or constructed with a discontinuity in one or both walls of a sealing region to intentionally interrupt the engagement between cooperating surfaces of container body  152  and lid  153 . 
         [0033]    In the embodiment illustrated in  FIGS. 8A and 8B , discontinuity feature  50  is present within lid  153  within the sealing region formed by outer wall  136  and the cooperating wall on body  152  (not illustrated). In particular, discontinuity feature  50  is a rib  54  present in outer wall  136  of lid  153 . Rib  54  extends the entire length of sealing arrangement  125  around container  150 . Discontinuity feature  50 , i.e., rib  54 , creates a discontinuity to facilitate easy removal of lid  153  from container body  152 . Such a rib  54 , or other raised or elevated discontinuity feature  50 , may also assist in applying pressure to the opposite side of the sealing arrangement  125 , to create a stronger continuous seal via the inner surface of the feature. 
         [0034]    Referring to  FIG. 9 , yet another alternate rigid container having a discontinuous sealing arrangement is illustrated as container  160 . Container  160  includes container body  162  and also a lid (not illustrated in  FIG. 9 ) that is removable and replaceable onto container body  162 . The lid inhibits access to the interior volume of container body  162 . 
         [0035]    Similar to the previous embodiments, each of container body  162  and its lid includes surfaces that cooperatively engage at sealing regions of a sealing arrangement. These surfaces are configured to engage (e.g., frictionally) with each other. In accordance with this disclosure, the sealing arrangement is configured or constructed with a discontinuity in one or both walls of a sealing region to intentionally interrupt the engagement between cooperating surfaces of container body  162  and its lid. 
         [0036]    In the embodiment illustrated in  FIG. 9 , discontinuity feature  50  is present within container body  162 . In particular, discontinuity feature  50  is an aperture  56  through a portion of the sealing region including outer walls of the sealing arrangement. Aperture  56  is present in a radiused corner of container body  162 . Aperture  56  facilitates removal of any lid sealed onto container body  162 , by providing a discontinuity in the sealing region. Aperture  56  also allows liquid, e.g., water, to drain from container body  162  when inverted, e.g., for drying after washing, such as in a dishwasher. 
         [0037]    Overall, discontinuity feature  50  is sufficiently sized (e.g., deep, tall, wide) to form a discontinuity in a sealing region between the cooperating surfaces of the lid and the container body to which it seals. For example, indent  52  (see  FIGS. 1 and 3B ) is sufficiently deep to provide a discontinuity in the sealing region between lid  30  and container body  20 . In that embodiment, indent  52  is sufficiently deep so that container outer wall  26  and lid outer wall  36  do not have continuous engagement therebetween. In another example, rib  54  (see  FIG. 8B ) is sufficiently tall or high to provide a discontinuity in the sealing region between lid  153  and container body  152 . In another example, aperture  56  has a sufficient area (width×height) to provide a discontinuity in the sealing region between the lid and container body  162 . 
         [0038]    Discontinuity feature  50  is located in a sealing region of a sealing arrangement (e.g., sealing arrangement  25  or  125 ), such as, for example, in inner side wall  22 , top wall  24 , outer side wall  26  of container body  20  or inner side wall  32 , top wall  34 , outer side wall  36  of lid  30 . It is understood that other configurations of sealing regions will have different surfaces. Discontinuity feature  50  can extend or occupy only a portion of the wall or surface within a sealing region, the entire height of the wall or surface, or additionally be present in or extend to other surfaces, such as, for example, onto removal tab  35 . 
         [0039]    Containers  10 ,  110 , etc. according to this disclosure are plastic containers. The plastic is typically thermoplastic, although thermosetting materials could be used. Examples of suitable plastic materials include polyethylene (both HDPE and LDPE), polyethylene terephthalate (PET), polypropylene, and polystyrene. Materials such as polyvinyl chloride (PVC) may also be used, but are typically more expensive. These polymeric or plastic materials can be made from typical petroleum-based materials (as is conventional), or, these and other materials could be made from natural materials such as corn and other starch sources. Other materials similar to plastic and suitable for the containers of the present invention are paperboard, hardboard, and pressboard. A polymeric film or layer may be present on the surface of the material to enhance resistance to moisture (e.g., increase waterproofing) of non-plastic materials. Plastics, and the other suitable materials, are sufficiently rigid so that the container maintains its shape without collapsing or wrinkling under normal use conditions. In most embodiments, the container body and lid are made from the same polymeric material. 
         [0040]    In most embodiments, depending on the material used for the container, the container is blow molded or press molded. Other suitable forming techniques include injection molding, although this forming technique is typically more expensive. 
         [0041]    For blow molded or press molded containers, both the container body and lid, typically have a thickness that is no more than 2 mm, often no more than 1 mm. Depending on the material used for the container, the thickness could be no more than 0.7 mm or no more than 0.5 mm. Of course, thinner containers would also be suitable. A disposable container should be sufficiently thick and rigid to withstand a single use, including microwave exposure. In some embodiments, the container is sufficiently rigid to withstand use over several days, including repeated daily use, multiple microwave exposures, and dishwasher temperatures. 
         [0042]    The above description and the attached drawings provide a description of various embodiments for improving the openability and operability of a rigid container. It is understood that the various elements and details of the discontinuity features illustrated in the figures and/or discussed above are interchangeable among the various container designs, and that variations of the various elements and details are within the scope of this disclosure. Additionally, the various elements and details of the discontinuity features can be used generally any sealing arrangement and/or sealing region configuration. Since many embodiments of the disclosure can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.