Abstract:
A self peelable seal having one or more layers for sealing containers by heat induction, conduction, or other means and having a stiffening structure. A portion of the seal is axially retained within a closure thereby allowing the peelable seal to be loosened from the container neck by placing a lifting force on the seal with the closure upon removal of the closure from the container.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This patent application is a continuation-in-part of and claims priority to and benefit from, currently pending, U.S. Nonprovisional patent application Ser. No. 11/181,576, filed on Jul. 14, 2005, which is incorporated herein by reference. 

   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   REFERENCE TO A “SEQUENTIAL LISTING,” A TABLE, OR A COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON A COMPACT DISC 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to container inner seals, and, more specifically, to inner seals having a stiffening structure which promotes ease of removal by allowing the user to loosen or remove the inner seal by flicking an overhanging portion with a finger or by retaining a portion of the seal in the closure. 
   2. Description of the Related Art 
   In view of the need for airtight inner seals on containers for food, medicine, and the like, closures have been developed which incorporate an inner seal bonded with a sealant to an upper rim of a container rim (i.e., the landing area of the container neck). Traditional inner seals typically have an integral pull tab to grip to facilitate removal of the inner seal, or no pull tab at all, forcing the user to resort to sharp objects to scrape, puncture, or break the inner seal. These traditional inner seals thus have numerous shortcomings. Although inner seals having integral tab portions are designed for gripping, end users—particularly the elderly—may find it difficult forming the required thumb and forefinger connection to pinch and pull the tab of the inner seal up and away form the upper container rim. Scraping or puncturing the inner seal with sharp objects such as knives can be dangerous to the end user. Therefore, there is a need for inner seals which are easily removed by the end user, particularly those who cannot pinch and pull a tab, and that do not require sharp and dangerous objects to puncture the inner seal. 
   SUMMARY OF THE INVENTION 
   In view of known deficiencies associated with earlier inner seals, there is provided an inner seal or liner having one or more layers. The inner seal has a central portion or body and optionally an overhanging portion extending beyond the margin or fringe of the central portion of the inner seal. In a single-layer inner seal, the inner seal includes a stiffening structure, such as a co-extruded film actually consisting of a plurality of materials. In a multi-layer inner seal, the inner seal includes the stiffening structure (or layer), and can further include an intermediate layer and a structure adapted for sealing or bonding the inner seal against an upper rim of a container (or landing area of a container neck). These layers may be stacked in the order recited, and are secured together in a composite sheet with adhesives known in the art. 
   In an embodiment of the seal having an overhanging portion, the overhanging portion may circumscribe the periphery of the central portion or body of the inner seal, and includes the stiffening structure, which facilitates removal of the inner seal by flicking the overhanging portion with a finger or retaining it within the closure. In an alternative embodiment, the seal has a post with a head extending through a hole in the top wall of the closure. The head has a larger diameter than the hole in the closure top wall, thus retaining the seal within the closure. In this embodiment the seal need not have an overhanging portion to be retained within the closure. The invention thus provides an inner seal easily removed not by pinching and pulling a tab, which some elderly people in particular might find difficult to perform, or by gouging the seal with a sharp object, which is dangerous, but by flicking an overhanging portion or by retaining the inner seal within the closure so that the inner seal is loosened or removed from the landing area of the container neck. The inner seal may be of any size or shape of inner seals known in the art, such as disc-shaped. 
   For a better understanding of the present invention, together with other and further objects thereof, reference is made to the following description, taken in conjunction with the accompanying drawings, and its scope will be pointed out in the appending claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The aspects and advantages of the present invention will be better understood when the detailed description of the embodiments taken in conjunction with the accompanying drawings, in which: 
       FIG. 1  is a perspective view of a peelable seal of the present invention on a container in a use condition; 
       FIG. 2  is an exploded view, in section, of a peelable seal with a container and a cap, according to an embodiment of the present invention; 
       FIG. 3  is a perspective view of a peelable seal of the present invention; 
       FIG. 4  is a cross-sectional view of a peelable seal of the present invention in a cap having a seal retainer cooperating with an overhanging portion; 
       FIG. 5  is a cross-sectional view of a peelable seal of the present invention in a closure having a seal retainer wherein the closure is on a container in a use condition; 
       FIG. 6  is a cross-sectional view of a peelable seal of the present invention in a cap having a seal retainer that also functions as a top wall of the cap; 
       FIG. 7  is a cross-sectional view of a peelable seal of the present invention in a cap having an alternative embodiment of a seal retainer; 
       FIG. 8  is a cross-sectional view of a peelable seal of the present invention in a cap on a container having yet another embodiment of a seal retainer where the seal does not extend beyond the neck of the closure; 
       FIG. 9  is a cross-sectional view of a peelable seal of the present invention in a cap having cavity with an extension from a seal residing therein; 
       FIG. 10  is a cross-sectional view of a peelable seal of the present invention in a cap having an extension from an inner central portion engaging a central cavity within a seal; 
       FIG. 11  is a top-sectional view of a peelable seal of the present invention having a stiffening layer with a cross-sectional area less than that of the seal; and 
       FIG. 12  is a cross-sectional view of a peelable seal of the present invention in a closure having a seal retainer wherein the closure is on a container in a use condition and has a peripheral stiffening structure. 
   

   DETAILED DESCRIPTION 
   While this invention is susceptible of embodiments in many different forms, there are shown in the Figures and will herein be described in detail, embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention, and is not intended to limit the broad aspects of the invention to the embodiments illustrated. 
   As shown in  FIG. 1 , a peelable seal  12  having a central body portion  13  with an overhang portion  18  is attached to a neck  14  of a container  10 . The seal  12  is easily loosened with the “flick” of the meat of a finger  50 , so that it may be readily peeled off. 
   An embodiment of the peelable seal of the present invention is generally disc-shaped as shown in  FIGS. 1 ,  2  and indicated by the numeral  12 . The seal  12  can be associated with a wide variety of closure-container combinations, and the closure-container combination depicted in the Figures is shown as an example only. As shown in  FIG. 2 , the peelable seal  12  is sealingly secured over the opening to the neck  14  of container  10 . Neck  14  is provided with outer container threads  16  which are engageable with closure engaging threads  24  of closure  20 . Closure  20  is further provided with a backing  22  which is a resilient structure separate or integral with the closure  20 . 
   As shown in  FIG. 2 , the seal  12  may be formed in a single layer with a central portion or body  13 , and an overhanging portion  18  extending beyond the margin or fringe of the central portion  13  of the seal  12 . The seal  12  may also include a plurality of layers, as is best shown in  FIG. 3 , including a sealant  128 . As shown in  FIG. 2 , a sealant  15  (or bonding layer), is used for attachment to the rim of neck  14 . The sealant may be formed of polypropylene, polyethylene ethylene vinyl acetate copolymer (EVA), polyester or a similar heat sealable material having relatively low density and tensile strength, and applied to the seal  12  on a side adjacent to the rim of the neck  14 . Preferably, the sealant  15  would be the same material as the container  10 . 
   In a single-layer seal  12  configuration, the seal  12  may include a stiffening structure, such as a co-extruded film actually consisting of a plurality of materials. The single-layer seal  12  configuration would be a construction in which a hot iron (not shown) is used to bond the seal to the upper rim of a container  10  (or landing area of a container neck  14 ). The materials must be stiff such that the seal  12  could be “flicked” as shown in  FIG. 1  to loosen it, and then peeled off without the need to form the forefinger and thumb gripping configuration. In the single-layer seal configuration, the stiffening structure may be as thin as about 0.010 inches thick, and the sealant may be about 0.0001 inches thick. 
   A multi-layer seal  120  as shown in  FIG. 3  may include a layer  122  of a stiffening structure; an intermediate layer  126 ; and a sealant structure  128 . The intermediate layer  126  may be a foil layer, and may be any metallic foil, preferably a stiff metallic material such as for example, aluminum. The bottom of sealant structure  128  can be adapted for sealing or bonding the seal against the upper rim of a container  110  (or landing area of a container neck). These layers may be stacked in the order recited, and are secured together in a composite sheet with adhesives known in the art. In defining the stacked layer seal  120 , seal  120  includes a central body portion  113  which covers the opening of a container with an outer peripheral edge or overhanging portion  118 . In this scenario, the layer  122  would be from about 0.010 to 0.25 inches of combined backing materials for stiffening, the intermediate layer would be from about 0.001 inches thick to about 0.010 inches thick and the sealant would be from about 0.0001 to 0.0002 inches thick, for an overall thickness of from about 0.01 inches to about 0.025 inches. 
   The multi-layer peelable seal  120  configuration is comprised of a layer  122  of about 0.0120 inches thick, an intermediate layer  126  of about 0.0015 inches thick, and a sealant  128  of about 0.0010 inches thick, for an overall thickness of about 0.0145 inches. In this configuration, the layer  122  includes about 0.0020 inches of polyester (PET) and about 0.0100 inches of polypropylene (PP). 
   In yet another multi-layer seal configuration, seal  120  is comprised of a layer  122  of about 0.0410 inches thick, an intermediate layer  126  of about 0.0015 inches thick, and a sealant  128  of about 0.0010 inches thick, for an overall thickness of about 0.0435 inches. In this configuration, the layer  122  includes about 0.0400 inches of rubber modified polypropylene thermoplastic elastomer and about 0.0010 inches of PP. The backing material which provides stiffening structure to the top layer  122  is generally selected from any solid material providing an adequate stiffening structure such as, for example, polyethylene terephalate (PET), polypropylene (PP), Nylon, polyethylene (PE), polyvinylchloride (PVC), styrene, ethylene-vinyl-acetate (EVA), ethylene-vinyl-alcohol (EVOH), Vinyl, foams of the preceding materials, paper, a stiff metallic material such as aluminum or steel, or combinations thereof. The preferred backing material is PET, PP, PVC, a stiff metallic material or paper. 
   The peelable seal  12  or  120  may be applied to a container in a conventional manner. The seal  12  or  120  typically is placed inside a closure  20  by a closure manufacturer, and the closures  20  typically are supplied to a packager of the container with the seals  12  or  120  retained within the closure  20 . The seal  12  or  120  is sealed to a container  10  by methods that will be recognized by those skilled in the art. The closure  20  is attached to the neck  14  of the container  10 . The central portion  13 ,  113  or body of the seal  12 ,  120  shown in the figures is of substantially the same size and configuration as the opening or mouth of the container  10 . In the embodiments shown, the seals  12 ,  120  include the overhanging portion  18 ,  118  circumscribing the peripheral edge of the body  13 ,  113  of the seal  12 ,  120 . The depth of the overhanging portion  18 ,  118  extends from the peripheral edge of the body portion  13 ,  113  beyond the rim of the container  10  usually from about 0.0050 inches to about 0.2500 inches. The preferred depth of the overhanging portion  18 ,  118  is about 0.0620 inches. The overhanging portion  18 ,  118  facilitates removal of the seals  12 ,  120  by one opening the container  10 . Instead of pinching and pulling a tab with the thumb and forefinger, or having to remove the seal with a knife or other sharp object, as in other conventional seals, the user flicks the overhanging portion  18 ,  118  with the meat of the finger  50  to loosen it, and the stiffening structure provides the rigidity or resistance so that when the meat of the finger  50  meets the overhanging portion  18 ,  118 , the seals  12 ,  120  pop up from the land area of the neck. The seals  12 , 120 , in other words, are not flexible like traditional inner seals. 
     FIG. 4  shows peelable seal  412  of the present invention in cap  400  having seal retainer  430 . Peelable seal  412  may be applied to a container in a conventional manner. Seal  412  typically is placed inside closure  400  by a closure manufacturer and rotatingly axially retained therein by seal retainer  430 . In this embodiment, seal retainer  430  is an extension of helical thread  424  having substantially a zero pitch near top wall  411 . Seal  412  is sealed to a container by methods that will be recognized by those skilled in the art. The central portion  413  of seal  412  is of substantially the same size and configuration as the opening or mouth of a container neck with which it will be sealed. In this and other embodiments shown, seals  12 ,  120 ,  412 ,  512 ,  612 , and  712  include an overhanging portion. In this embodiment, overhanging portion  418  circumscribes the peripheral edge of central portion  413  of the seal  412  beyond retainer  430 . The overhanging portion  418  facilitates removal seal  412  from a container upon the removal of closure  400  from a container. The user removes closure  400  from the container by rotating closure  400  in a counterclockwise direction engaging helical thread  424  on the inner annular surface of side wall  410  with a helical thread on the closure. Overhanging portion  418  is retained by seal retainer  430  and seal  412  is removed there with. 
     FIG. 5  shows peelable seal  512  of the present invention in closure  500  having seal retainer  530  on container  509  in a use condition. Seal  512  typically is placed inside closure  500  and retained therein with seal retainer  530 . In this embodiment, seal retainer  530  is a coextensive bead circumscribing the inner annular surface of side wall  510  a sufficient distance from top wall  511 . Seal  512  is shown sealed to container neck  514  of container  510 . The central portion  513  of seal  512  is of substantially the same size and configuration as the opening or mouth of neck  514  of container  509  with which it is sealed. Seal  512  has overhanging portion  518  circumscribing the peripheral edge of central portion  513  of the seal  512  beyond retainer  530 . The overhanging portion  518  facilitates removal seal  512  from container  509  upon the removal of closure  500  from container  509 . The user rotatingly removes closure  500  from container  509  with a counter clockwise force causing container threads  516  to interact with closure threads  524 . Overhanging portion  518  is retained by seal retainer  530  and seal  512  is removed there with. Also shown in this embodiment is tamper evident ring  525  which is an optional feature that may be included with any embodiment of the present invention. 
     FIGS. 6 and 7  show peelable seals  612  and  712  of the present invention in a cap having seal retainers  630  and  730  respectively where seals  612  and  712  function as a top wall of caps  600  and  700 . Peelable seals  612  and  712  may be applied to a container in a conventional manner. Seals  612  and  712  typically are placed inside closures  600  and  700  and retained therein by seal retainers  630  and  730 . Seal retainer  630  is a substantially uniform retaining bead circumscribing the inner annular surface of cap side wall  610  while seal retainer  730  is an interrupted retaining bead circumscribing the inner annular surface of cap side wall  710 . The central portions  613  and  713  of seals  612  and  712  function as top walls of closures  600  and  700 . Seals  612  and  712  have overhanging portions  618  and  718  residing above seal retainers  630  and  730  and below top seal retainers  611  and  711 . Top seal retainers  611  and  711  are shown as an inward depending side wall and have a thickness sufficient to provide a sealing force on the top periphery of seals  612  and  712 . It is to be understood that top seal retainers  611  and  711  are optional since a seal is formed between seals  612  and  712  and a container neck. Seal retainers may be in the form of a retaining bead or even an intermittent retaining bead. Overhanging portions  618  and  718  circumscribe the peripheral edge of central portions  713  and  813  of seals  612  and  712  beyond retainers  630  and  730 . The overhanging portions  618  and  718  facilitate removal seals  612  and  712  from a container upon the removal of closures  600  and  700  from a container. 
     FIG. 8  is a cross-sectional view of a peelable seal  812  of the present invention in cap  800  on container  809 . Seal  812  may be applied to a container in a conventional manner. Seal  812  typically is placed inside closure  800  by a closure manufacturer and retained therein by seal retainer  813 . Seal retainer  813  is in the form of a post extending upward from seal  812  having a head with a diameter wider than the post. Closure  800  has a hole centrally oriented in a top wall  811  for receiving seal retainer  813  and having a diameter less than the diameter of the head of seal retainer  813 . Seal  812  is sealed to a container by methods that will be recognized by those skilled in the art. The diameter of seal  812  is of substantially the same size and configuration as the opening or mouth of container neck  814  with which it will be sealed. Seal retainer  813  facilitates removal seal  812  from container  809  upon the removal of closure  800  from container  809  by placing an axial force on seal  812  when closure  800  is being removed from container  809 . The user removes closure  800  from container  809  by rotating closure  800  in a counterclockwise direction engaging helical thread  824  on the inner annular surface of side wall  810  with helical thread  816  on container neck  814 . Seal retainer  813  is retained by top wall  811  and seal  812  is removed there with. 
     FIG. 9  shows peelable seal  918  of the present invention in cap  900 . The seal retainer is in the form of an axial extension  913  from a central portion of seal  912  residing in cavity  914  within top wall  911  of closure  900 . Also shown here is closure side wall  910  annularly depending from top wall  911  having helical thread  924  on an inner annular surface thereof. 
     FIG. 10  shows peelable seal  1018  of the present invention in cap  1000 . The seal retainer is in the form of an axial extension  1013  from a central portion of top wall  1011  of closure  1000  having at least one outwardly extending flange  1015  extending into cavity  1014  in seal  1018  where at least outward extending flange  1015  rotatingly engages seal  1018 . At least one layer  1012  of seal  1018  encloses seal  1018  on a sealing side. Also shown here is closure side wall  1010  annularly depending from top wall  1011  having helical thread  1024  on an inner annular surface thereof. 
     FIG. 11  is a top-sectional view of cap  1100  having peelable seal  1118 . The seal retainer is in the form of an axial extension  1113  from a central portion of a top wall of closure  1100  having at least one outwardly extending flange  1115  extending into cavity  1114  in seal  1118  where at least outward extending flange  1115  rotatingly engages seal  1118 . At least one layer  1112  of seal  1118  encloses seal  1118  on a sealing side. At least one layer  1117  of seal  1118  provides a stiffening structure to seal  1118 . Also shown here is closure side wall  1110  annularly depending from a top wall of closure  1100 . 
     FIG. 12  shows peelable seal  1212  of the present invention in closure  1200  having seal retainer  1230  on container  1209  in a use condition. In this embodiment, seal retainer  1230  is a coextensive bead circumscribing the inner annular surface of side wall  1210  a sufficient distance from top wall  1211  rotatingly retaining an outer peripheral portion  1218  of seal  1212 . Seal  1212  is shown sealed to container neck  1214  of container  1209 . Peripheral portion  1218  of seal  1212  has at least one layer providing seal  1212  with a stiffening structure. Peripheral portion  1218  has a portion overhanging container neck retainer  1214  rotatingly engaging seal retainer  1230 . Also shown in this embodiment is optional tamper evident ring  1225  and container threads  1216  interacting with closure threads  1224 . 
   While there have been described several embodiments of the present invention, those skilled in the art will recognize that other and further changes and modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the true scope of the invention.