Patent ID: 8978346
Filing Date: 2015-03-17
Classification: B32B,B65B,Y10T

Abstract:
1. A multi-layer film for making pouches for containing flowable materials, said multi-layer film comprising the following layers in order, from an at least one inner sealant-layer to an at least one outer sealant-layer: (A) said at least one inner sealant-layer comprising polyethylene that is selected from the group consisting of: (i) an at least one low-density ethylene-alpha-olefin copolymer, (ii) a blend of said at least one low-density ethylene-alpha-olefin copolymer and an at least one ethylene homopolymer, wherein said ethylene homopolymer is made in a high-pressure polymerization process; and (iii) a blend of said at least one low-density ethylene-alpha-olefin copolymer and an at least one ethylene copolymer, wherein said ethylene copolymer is made in a high-pressure polymerization process; (B) a first at least one interposed layer adjacent to said at least one inner sealant-layer, said first at least one interposed layer comprising: (i) an at least one high-density polyethylene, or a blend of said at least one high-density polyethylene and at least one ethylene-alpha-olefin copolymer; (ii) optionally, an ethylene homopolymer made in a high-pressure polymerization process; (iii) optionally, an ethylene copolymer made in a high pressure polymerization process; and (iv) optionally, a second ethylene-alpha-olefin copolymer that is not the same as said at least one ethylene-alpha-olefin copolymer in (B)(i); wherein the centerline of said first at least one interposed layer is closer to the centerline of said at least one inner sealant-layer than to the centerline of said multi-layer film; (C) at least one core layer, adjacent to said first at least one interposed layer, said at least one core layer comprising polyethylene that is selected from the group consisting of: (i) at least one low-density ethylene-alpha olefin copolymer, (ii) a blend of said at least one low-density ethylene-alpha-olefin copolymer and an at least one ethylene homopolymer, wherein said ethylene homopolymer is made in a high-pressure polymerization process; and (iii) a blend of said at least one low-density ethylene-alpha-olefin copolymer and an at least one ethylene copolymer, wherein said ethylene copolymer is made in a high-pressure polymerization process; (D) a second at least one interposed layer adjacent to said at least one core layer, said second at least one interposed layer comprising: (i) an at least one high-density polyethylene, or a blend of said at least one high-density polyethylene and at least one ethylene-alpha-olefin copolymer; (ii) optionally, an ethylene homopolymer made in a high-pressure polymerization process; (iii) optionally, an ethylene copolymer made in a high pressure polymerization process; and (iv) optionally, a second ethylene-alpha-olefin copolymer that is not the same as said at least one ethylene-alpha-olefin copolymer in (D)(i); wherein the centerline of said second at least one interposed layer is closer to the centerline of said at least one outer sealant-layer than to the centerline of said multi-layer film; and (E) said at least one outer sealant-layer, comprising polyethylene that is selected from the group consisting of: (i) an at least one low-density ethylene-alpha-olefin copolymer, (ii) a blend of said at least one low-density ethylene-alpha-olefin copolymer and an at least one ethylene homopolymer, wherein said ethylene homopolymer is made in a high-pressure polymerization process; and (iii) a blend of said at least one low-density ethylene-alpha-olefin copolymer and an at least one ethylene copolymer, wherein said ethylene copolymer is made in a high-pressure polymerization process; wherein said multi-layer film thickness is in the range of from about 35 microns to about 66 microns; wherein a combined thickness of said first at least one interposed layer and said second at least one interposed layer is in the range of from about 10% to about 27% of the total thickness of said multi-layer film; wherein a combined thickness of said inner sealant-layer and said outer sealant-layer is in the range of from about 10% to about 27% of the total thickness of said multi-layer film; and wherein said at least one high-density polyethylene in said first at least one interposed layer and said second at least one interposed layer has a density of at least of about 0.950 g/cm.sup.3 and a melt-index of less than 1.05 dg/min.