Patent ID: 8137774
Filing Date: 2012-03-20
Classification: B32B,B65D,C08L,C09J,Y10T

Abstract:
1. A package comprising a multilayer structure having an easily peelable opening feature and a tight hermetic seal wherein the multilayer structure comprises at least one polychlorotrifluoroethylene fluoropolymer substrate layer, and wherein the multilayer structure is prepared by a method comprising the steps of: A. providing a polychlorotrifluoroethylene fluoropolymer substrate layer; B. providing a resin composition that, when tested substantially in accordance with ASTM F 904-98, peels cleanly away from a polychlorotrifluoroethylene fluoropolymer substrate layer, wherein said resin composition consists essentially of: C. selecting an additional material selected from the group consisting of polyesters, polyamides, polyolefins, polyethylene vinyl alcohols, polyethylene vinyl acetates, ethylene/acrylic acid copolymers and ionomers thereof, ethylene/methacrylic acid copolymers and ionomers thereof, polyvinyl chloride, polyvinylidene chloride, anhydride-modified polyolefins and mixtures thereof that has a viscosity sufficiently high to form a sheet or tape when extruded at a temperature of 190° C.; D. forming a multilayer coextrudate having at least two layers via coextrusion through a single die in the form of a film, a sheet or a tape, wherein i) a first layer of said extrudate comprises said resin composition of step B, ii) a second layer of said extrudate comprises said additional material of step C, and iii) said first layer is an outer layer of said multilayer coextrudate; E. contacting said multilayer coextrudate with said polychlorotrifluoroethylene fluoropolymer substrate layer such that said first layer comprising said resin composition of step B is in contact with and adjacent to said polychlorotrifluoroethylene fluoropolymer substrate layer; and F. applying sufficient heat and pressure for sufficient time to heat-seal said multilayer coextrudate to said polychlorotrifluoroethylene fluoropolymer substrate layer; thereby forming a multilayer structure characterized by a tight hermetic seal and easy peelability wherein the coextrudate peels cleanly away from the polychlorotrifluoroethylene substrate leaving the substrate intact.