Container seal

Abstract

A seal for a container of fine particulate materials that includes a sifter insert. The seal comprises a base that is secured over a plurality of holes in the insert by a releasable pressure-sensitive adhesive. A pull tab extends outwardly from an upper surface of said base. The pull tab is fixedly adhered to the upper surface of the base and extends outwardly away from a mid-section thereof. The pull tab is pivotable through 180 degrees about its connection point with the base and remains fixedly secured thereto when a pulling force is applied to the pull tab. The adhesive bond between the base and the insert is weaker than the adhesive bond between the pull tab and the base. Consequently, a pulling force applied to the pull tab removes the base from the insert and permits particulate material to be dispensed through the holes in the insert.

1 . A seal for a container system, said seal comprising:
 a base having an upper and a lower surface;   a laminate layer having a lower surface defining a first and a second region;   an undertab; said undertab being smaller than either of the upper surface of the base and lower surface of the laminate layer;   a first adhesive on the lower surface of the base adapted to form a releasable bond between the base and a container insert;   a second adhesive disposed between the first region of the laminate layer and a portion of the upper surface of the base, said second adhesive forming a fixed bond between the laminate layer and the base.   
   
   
       2 . The seal as defined in  claim 1 , further comprising an adhesive disposed between and fixedly bonding the second region of the laminate layer to the undertab; whereby said bonded undertab and second region of the laminate layer form a pull tab for removing the base from the container insert. 
   
   
       3 . The seal as defined in  claim 2 , wherein the first adhesive forms a weaker bond between the base and the container insert than the bond formed by the second adhesive between the base and first region of the laminate layer. 
   
   
       4 . The seal as defined in  claim 1 , wherein the base and the laminate layer are generally circular in shape and the undertab is generally semicircular in shape. 
   
   
       5 . The seal as defined in  claim 4 , wherein the undertab is adhered to the laminate layer in such a manner that the pull tab is semi-circular in shape and is pivotable about a diagonal of the circular base. 
   
   
       6 . The seal as defined in  claim 5 , wherein the pull tab is pivotable through 180 degrees relative to the upper surface of the base. 
   
   
       7 . The seal as defined in  claim 1 , wherein the base is comprised of a pressure sensitive semi-gloss paper. 
   
   
       8 . The seal as defined in  claim 1 , wherein the laminate layer is comprised of a 1 mil selfwound laminate. 
   
   
       9 . The seal as defined in  claim 1 , wherein the undertab is comprised of a non-pressure sensitive semi-gloss paper. 
   
   
       10 . In combination:
 a container having a chamber adapted to receive a fine particulate material therein; said container defining an opening through which said chamber is accessible;   an insert engageable in the opening of the container; said insert including a plurality of holes through which particulate material is dispensed from the chamber;   a removable seal for obstructing said holes in the insert prior to use; said seal comprising:
 a base; 
 a first adhesive applied between a lower surface of the base and the insert; 
 a pull tab extending outwardly from an upper surface of the base; 
 a second adhesive applied between the base and a portion of the pull tab; said second adhesive fixedly bonding said pull tab to the upper surface of the base; whereby application of an outwardly directed force to the pull tab breaks a bond between the first adhesive and the insert and permits the seal to be removed therefrom. 
   
   
   
       11 . The combination as defined in  claim 10 , wherein the seal further comprises a laminate layer having a first and second region; and an undertab; and wherein the second adhesive is applied between the first region of the laminate layer and the base, and between the second region of the laminate layer and the undertab; and wherein the undertab and second region substantially comprise the pull tab. 
   
   
       12 . The combination as defined in  claim 11 , wherein the pull tab extends outwardly away from an upper surface of the base. 
   
   
       13 . The combination as defined in  claim 12 , wherein the base is substantially circular in shape and the pull tab extends outwardly from the base along a diagonal thereof. 
   
   
       14 . The combination as defined in  claim 13 , wherein the pull tab is pivotable through 180 degrees about the diagonal. 
   
   
       15 . The combination as defined in  claim 10 , wherein the first adhesive is a pressure sensitive adhesive that forms a weaker releasable bond between the base and the insert. 
   
   
       16 . The combination as defined in  claim 15 , wherein the second adhesive is an emulsion acrylic adhesive that forms a strong non-releasable bond between the base and the pull tab. 
   
   
       17 . The combination as defined in  claim 10 , wherein the container comprises:
 a housing having a bottom wall, a peripheral side wall extending upwardly away from the bottom wall, and an upper wall terminating in a lip; and   an interior chamber defined and surrounded by the bottom wall, side wall and upper wall; and wherein the lip defines the opening through which the chamber is accessible.   
   
   
       18 . The combination as defined in  claim 17 , wherein the insert comprises:
 an insert bottom wall;
 an insert peripheral side wall extending outwardly away from the insert bottom wall; and wherein the insert side wall is complementary sized and shaped to interlock with the lip of the container base when the insert is press-fitted into the opening. 
   
   
   
       19 . A method for sealing a container and removing said seal, said method comprising the steps of:
 applying a pressure sensitive adhesive side of a seal to an insert in a container to bond said seal to said insert, said seal being placed so that a plurality of holes in the insert holes are all located within an area covered by said seal;   pivoting a pull tab that extends outwardly from an upper surface of said seal from a horizontal position to a substantially vertical position;   applying a sufficient force to said pull tab to release the bond between said seal and said insert; and   continuing to apply force to said pull tab until said seal is completely released from said insert.