Reclosable slide-on cover for a rectangularly flanged container
United States Patent Smith Apr. 8, 1975 1 1 RECLOSABLE SLIDE-0N COVER FOR A 3,272,422 9/1966 Miller 229/43 NTA 3.335939 8/1967 Robinson 229 43 RECTANGULARLY FLANGED C0 INER 3.561.668 2/l97l Bergstrom 229/43 Inventor: Ernesl Smith, Kansas y. 3676.159 7/1972 Fallowfield 229/43 1 Assignee: Phillips Petroleum p y- FOREIGN PATENTS OR APPLICATIONS samesv&#39;nm 0km 642,668 5/1964 Belgium .1 229/43 [22] Filed: May 10, 1973 [2|] App] NO 358 898 Primary E.\&#39;aminerEdward J. McCarthy [52] U.S. Cl 229/43; 220/41 [57] ABSTRACT [5|] Cl 365d 43/00 A slide-0n closure and a blank from which it can be [58] Field of Search 229/43; 220/41 formed are Provided to Cover 21 &#34;16191181119111 flanged open top container. The closure provides a relatively 1 References Cited sturdy reclosable covering for an open top, film or foil UNITED STATES PATENTS covered rectangularly flanged container which allows the containers to be stacked. M49925 8/l9l5 Leighton 229/43 3.021.001 2/1962 Dorofrio 229/43 9 Claims, 5 Drawing Figures RECLOSABLE SLIDE-ON COVER FOR A RECTANGULARLY FLANGED CONTAINER BACKGROUND OF THE INVENTION This invention relates to a container closure. In one aspect, this invention relates to closable containers. In another of its aspects, this invention relates to closures for flanged topped containers. In still another aspect of this invention, it relates to slidable closures for flanged topped containers. In yet another of its aspects, this invention relates to reclosable covers for containers.  
  Many products can be economically shipped and stored in flanged top containers. Containers having rectangularly flanged tops have found much use particularly in the food industry. Usually, these containers are covered with a film or metal foil covering to seal the food product from the atmosphere. This type of covering presents a problem in storage and shipping because it is not sufficiently substantial to permit stacking of the flanged containers without danger of the container above breaking through the covering of the lower containers in the stack.  
  It is therefore an object of this invention to provide a closure for a rectangularly flanged container such that the closure will provide strength and protection in stacking the containers.  
  It is another object of this invention to provide a container closure that will slip onto the flanged top of a container.  
  It is another object of this invention to provide a reclosable covering for a flanged top container. It is still another object of this invention to provide a blank from which the closure of this invention can be produced.  
  It is the overall object of this invention to provide a closure used in combination with a rectangularly flanged, open top container that can be slipped over the flanged top of the container and sealed, opened, and rescaled.  
  Other aspects, objects and the advantages of this invention will be apparent to those skilled in the art upon reading the specification and claims of this invention.  
 SUMMARY OF THE INVENTION The closure for a rectangularly flanged container of this invention comprises a rectangular central panel and hingedly attached to each of the four sides of this central panel along a scored line, a side panel of length equal to the side of the central panel to which it is attached and of a width sufficient to overlap the adjacent side panel to form a scalable surface with the adjacent side panel surfaces that are contiguous thereto when the side panels are folded against the central panel. A first side panel and a second and third side panel adjacent thereto have an amount of pressure sensitive adhesive sufficient to form a seal applied on each of the four surfaces that are contiguously paired when these three panels are caused to overlap by being folded against the central panel. The fourth side panel and its adjacent second and third side panels are caused to overlap by being folded against the central panel and the contiguous overlapping surfaces of these three panels are sealed together. The closure can be described as a central panel having narrow side panels attached to each of its sides running the length of each of the sides with three of the side panels folded back against the central panel and sealed to each other in that position with the fourth side panel being adapted to be folded against the central panel, but left in a position such that a plate can be slid past the open side and retained envelope fashion by the central panel and the prefolded side panels.  
  In one embodiment of the invention, a blank preform is provided from which the closure of this invention can be folded and produced. In another embodiment of the invention, the closure is shown in conjunction with a rectangularly flanged open top container.  
 BRIEF DESCRIPTION OF THE DRAWING For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawing in which:  
  FIG. 1 is a plan view of the blank sheet material from which the carton is formed;  
  FIG. 2 is a plan view of the blank of FIG. 1 formed into the closure of the invention;  
  FIG. 3 is a perspective view of the closure being slid into position on a rectangularly flanged open top container;  
  FIG. 4 is a perspective view of the closure having been slid into position but not sealed; and  
  FIG. 5 is a perspective view of the closure and container inverted to show the side panels sealed around the container flange.  
  Referring now to FIG. I, the embodiment of the invention illustrated is a blank comprising a rectangular central panel 1 having hingedly attached along a scored line 2, 3, 4 and 5 a side panel 6, 7, 8 and 9. Each side panel is equal in length to the side of the central panel to which it is attached. The width of the side panel is sufficient so that if a first side panel 7, a second side panel 6 and a third side panel 8 were folded against the central panel 1 the side panels, 6, 7 and 8 would overlap in the area 10, ll, 12 and 13 to form pairs of contiguous surfaces 10 and II or 12 and 13.  
  These contiguous surfaces can be sealed by applying adhesives, here shown as spots 10, 11, 12 and 13 of pressure sensitive adhesive to the contiguous surfaces. As shown in FIG. I the adhesive spots 11 and 12 would be on the front side of panel 7 while the adhesive spot 10 on side panel 6 and adhesive spot 13 on side panel 8 would be on the back side of the side panel so that when the side panels were folded against the central panel 1 the adhesive spots would be paired on the contiguous surfaces I0, 11 and l2, 13.  
  The adherence of the side panels to each other has been illustrated above with pressure sensitive adhesive which is suitable to form a seal that can be opened then resealed. Referring now to FIG. 2, it will be seen that the folded blank forming the closure of this invention has side panel 6, 8 and 9 folded against the central panel 1 and permanently sealed, as shown above, where the side panels overlap to form contiguous surfaces at 14 and 15. In FIG. 2, side panel 7 has not been folded along scored line 3 and adhesive points 10, l1, l2 and 13 are shown on the front side of the open centered, envelopedike packet formed by the closure.  
  Referring now to FIG. 3, the closure of FIG. 2 is shown being slid into position on a rectangularly flanged open top container. The central panel I of the closure forms the top surface of the closed container 16. Side panel 7 is held in position away from the flange 17 of the container 16 while the flange 17 is slid between central panel 1 and the side panel 6 and 8 (barely visible in this view). It will be noted that the central panel 1 of the closure must be sufficiently larger than the flange 17 to permit the side panels 6, 7, 8, 9 to be folded and leave enough space between the folds and the flange to allow easy sliding of the closure into position on the flanged top.  
  Also shown in FIG. 3 in cut-away view is a sheet of material 18 that can be metal foil or plastic film attached over the upper flange 17 of the container to seal the container contents from the atmosphere. This fig ure illustrates that the closure of this invention while not providing sealing from the atmosphere itself can be used in conjunction with a flanged top container that has been sealed from the atmosphere.  
  In FIG. 4, the closure of FIG. 2 is shown after having been slid into position on a rectangularly flanged open top container. Here again, the central panel 1 of the closure forms the top surface of the closed container 16. Side panel 7 has been folded down, but has not been sealed by pressing together the pressure sensitive adhesive sealing spots (shown in FIG. 2 as 10, ll, 12 and 13).  
  FlG. has been provided to show an inverted view of the closure and container with the closure sealed on the container flange. In this view, it can be seen that side panels 6, 8 and 9, which have been folded flat against the central panel and sealed at their overlapping points (such as 14) have formed an open centered envelope-type structure into which the upper flange 17 of the container 16 has been slid. The remaining side panel 7 has been folded back to seal the pressure sensitive adhesive spots at the overlapping points 11 and 12. This view shows that the side panels 6, 7, 8 and 9 must be narrower than the width of the flange 17 of the top of the container 16.  
  Aithough the container shown in the figures of the drawing is a rectangular tray like container, the concept of this invention embraces any container that has a rectangularly flanged top. The container could have, for instance, a cylindrical base, a bag-like base, or any other shape as long as the top is adapted into the shape ofa rectangular flange. The material of Construction of the container is not pertinent to this invention.  
  The material of construction of the closure of this invention can be any material suitable for being shaped into a blank and folded into the shape of the closure. The construction material must have sufficient strength to provide enough rigidity to the closure to prevent the closure from caving in or tearing when in position over the open top of a flanged top container. Particularly suitable flexible sheet materials are thermoplastics, paper products, and laminates of paper products and thermoplastics or microcrystalline waxes. At present, the preferred material of construction is paperboard.  
  in the embodiment in which the container is sealed away from the atmosphere before being covered with the closure of the invention, the top of the container can be covered and sealed with a material chosen from among plastic film, metal foil, and fibrous sheeting which is heat sealed or adhesively sealed to the container flange.  
  The closure can have its side panels sealed together by any appropriate sealant depending on the material of construction of the closure. In some instances, heat sealing can be appropriate. In others, an adhesive must be used.  
  Suitable pressure sensitive adhesives are well known in the art for use in making one side panel resealable, so that the closure can be slid off the container and then returned to position to close the container top and the closure resealed in the closed position. These pressure sensitive adhesives will be those adpated for use with specific materials of construciton where such adaptation is necessary.  
  Reasonable variation and modification are possible within the scope of the foregoing disclosure, the drawing and the appended claims of the invention.  
 1 claim:  
  1. A blank adapted to be folded into a closure for enclosing a rectangular flange surrounding the opening of a container, said blank comprising: a rectangular cen tral panel and hingedly attached to each of the four sides of said central panel along a scored line, a side panel wherein the length of the side panel is equal to the side of the central panel to which it is attached and wherein the width of the side panel is sufficient to overlap the adjacent side panels to form a scalable surface with the adjacent side panel surfaces that are contiguous thereto when said side panels are folded against said central panel.  
  2. A blank of claim 1 wherein a first side panel and a second and a third side panel adjacent thereto have an amount of pressure sensitive adhesive sufficient to form a seal applied on each of the four surfaces that are contiguously paired when said side panels are overlapped by being folded against said central panel.  
  3. A blank of claim 2 wherein said second and third side panels and the fourth side panel are folded against said central portion thereby overlapping and the contiguous overlapping surfaces are sealed together.  
  4. A closure for enclosing a rectangular flange surrounding the opening of a container, said closure comprising: the folded blank of claim 3 wherein the rectangular central portion is of lateral dimensions sufficient to cover the rectangular flange surrounding the opening of said container and to permit the hingedly attached side panels to be folded beneath the container flange, said side panels of a width less than the width of the underside of said container flange.  
  5. In combination, a container having an opening surrounded by a rectangular flange and a closure of claim 4 adapted to cover said container.  
 6. In combination, the container and closure ofclaim 5 wherein all side panels of the closure are sealed to the tic or microcrystalline waxes.