Resealable Film Structure

Abstract

A reclosable film structure for a package is disclosed, in particular a reclosable lap seal, comprising a multiple layer film with an interior pressure sensitive adhesive layer, and methods of manufacture thereof. The pressure sensitive adhesive layer is positioned between a first and a third layer on either side of the pressure sensitive adhesive layer and is continuous throughout the package. The package is heat sealed at an open end to initially close the package by folding over an outer lap seal segment onto an inner lap seal segment and heat-sealing together. Upon opening the package at the lap seal, the package delaminates between the first and second layers along one of the lap seal segments, thus exposing the pressure sensitive adhesive layer to facilitate reclosing the package, oriented away from the package interior and away from the food removal path to maintain the adhesion strength by avoiding food contact.

1 . A reclosable lap seal for a package comprising:
 an inner lap seal segment and an outer lap seal segment each having at least a first layer, a second layer having a pressure sensitive adhesive, and a third layer; and   a heat seal formed in a region between the first layer of the inner lap seal segment and the third layer of the outer lap seal segment, the heat seal strength between the first and third layers being greater than the heat seal strength between the second and third layers, and the heat seal strength between the second and third layers being greater than the heat seal strength between the first and second layers effective to permit the first layer to separate from the second layer of one of the inner lap seal segment and the outer lap seal segment upon opening, to expose the pressure sensitive adhesive of the second layer and oriented away from a package interior.   
     
     
         2 . The film according to  claim 1 , wherein the first layer on the inner lap seal segment separates from the second layer of the inner lap seal segment to expose the pressure sensitive adhesive of the second layer on the inner lap seal segment. 
     
     
         3 . The film according to  claim 1 , wherein the first layer on the outer lap seal segment separates from the second layer of the outer lap seal segment to expose the pressure sensitive adhesive of the second layer attached to the inner lap seal segment. 
     
     
         4 . The film according to  claim 1 , wherein the first layer has an inner side that is not heat-sealable and an outer side that is heat-sealable. 
     
     
         5 . The film according to  claim 1 , wherein the second layer is adjacent the first layer at an outer side of the second layer and the inner side of the first layer. 
     
     
         6 . The film according to  claim 1 , wherein the third layer is one of a two-side heatsealable film and a single-side heat-sealable film, adjacent an inner side of the second layer. 
     
     
         7 . The film according to  claim 1 , wherein the first layer is a coextruded polypropylene layer, where the inner side has a low surface energy to allow for delamination from the second layer. 
     
     
         8 . The film according to  claim 1 , wherein the second layer is selected from the group consisting of an extrudable styrene block copolymer, natural rubber, acrylates, silicones, poly (iso-butylene), polyvinyl ethers, and polybutadiene. 
     
     
         9 . The film according to  claim 1 , wherein the second layer is a coating and is coated onto one or both of the first and third layers. 
     
     
         10 . The film according to  claim 1 , wherein the first and the third layers are both polyolefin layers. 
     
     
         11 . The film according to  claim 1 , wherein the inner side of the first layer has a metallized surface and the outer side is a heat-sealable layer. 
     
     
         12 . The film according to  claim 1 , wherein the lap seal is positioned at an edge of the package opposite a fold seam. 
     
     
         13 . The film according to  claim 1 , wherein a second edge seal and a third edge seal are formed to seal the package at a second edge and a third edge, respectively, transverse to a fold seam and the heat seal, and are either lap or fin seal arrangements. 
     
     
         14 . A reclosable package comprising:
 a web of film having at least a first layer, a second layer having a pressure sensitive adhesive, and a third layer;   a food product contained therein;   a reclosable lap seal contained in the package for gaining access to the food product in a package interior, the reclosable lap seal having an inner lap seal segment and an outer lap seal segment each having the at least three layers of film; and   a heat seal formed in a region between the first layer of the inner lap seal segment and the third layer of the outer lap seal segment, the heat seal strength between the first and third layers being greater than the heat seal strength between the second and third layers, and the heat seal strength between the second and third layers being greater than the heat seal strength between the first and second layers effective to permit the first layer to separate from the second layer of one of the inner lap seal segment and the outer lap seal segment upon opening, to expose the pressure sensitive adhesive of the second layer and oriented away from the package interior.   
     
     
         15 - 20 . (canceled)