Patent ID: 8084109

Claim:
A PVDC-Polyolefin co-extruded thermal-formed high-blocked composite packaging material, comprising: a top film and a bottom film having a cavity therebetween for containing a packaged object; wherein the top film, as a display side of a package, is a multilayer film that is transparent or is printed thereon graphic and text information of the packaged object; and the bottom film, as a forming side of the package, is a multilayer film suitable for thermoforming, vacuum surface packaging or inflation packaging, and has a thermal sealing; wherein: a. the top film is a film with seven or more layers, having a basic structure as below: BOPP/PE-TIE-PVDC-TIE-PP-PE i. PVDC is selected from one of the following three film-class materials: homopolymerized polyvinylidene chloride; copolymer of methyl acrylate and polyvinylidene chloride; and copolymer of chloroethylene and polyvinylidene chloride; ii. PE is polyethylene or modified polyethylene with a density of 0.92±0.03 g/cm 3 that is a mixture of polyethylene and at least one of the following four materials: metallocene polyethylene, with a density of 0.86˜0.94 g/cm 3 ; thermoplastic polyolefin elastomer, with a density of 0.86˜0.905 g/cm 3 ; metal-ion polymer of sodium and zinc, with a density of 0.92˜0.94g/cm 3 ; and ethylene-vinyl acetate copolymer, with a density of 0.92˜0.945 g/cm 3 ; iii. BOPP is biaxially oriented polypropylene; iv. TIE is adhesive resin; v. PP is polypropylene; vi. “/” stands for solventless dry-type compound forming and “-” stands for multilayer cast or multilayer blowing film coextrusion compound forming; and vii. the PE-TIE-PVDC-TIE-PP-PE is formed by multilayer cast or multilayer blowing film coextrusion, and is compounded with BOPP in a solventless dry way; b. the bottom film is a film with five or more layers, having a basic structure as below: PP-TIE-PVDC-TIE-PE i. PP is polypropylene or modified polypropylene with a density of 0.91±0.03 g/cm 3 that is a mixture of polypropylene and at least one of the following four materials: metallocene polyethylene, with a density of 0.86˜0.94 g/cm 3 ; thermoplastic polyolefin elastomer, with a density of 0.86˜0.905 g/cm 3 ; ethylene-vinyl acetate copolymer, with a density of 0 . 920 . 945 g/cm 3 ; and high-density polyethylene, with a density of 0.94˜0.96 g/cm 3 ; ii. PVDC is the same with that in the top film; iii. PE is the same with that in the top film; and iv. the PP-TIE-PVDC-TIE-PE is formed by multilayer cast or multilayer blowing film coextrusion.