# US 9,434,138 B2 · Peelable, non-sticky, heat-sealable film for packaging fatty and pasty foods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,434,138 B2 - Document ID: US9434138B2 - Status: Granted - Kind: B2 - Application number: 14/257,367 - Filed: 2014-04-21 - Published: 2015-10-22 - Granted: 2016-09-06 - Earliest claimed: 2014-04-21 - Assignees: Inteplast Group Corporation - Applicants: Inteplast Group, Ltd. - Inventors: Rafael E. Bayona P.; Gregory G. Gillis; Paul T. Alder - Web page: https://patentgrep.com/patent/US9434138B2 ## CPC - B32B 27/08: of synthetic resin - B32B 7/06: permitting easy separation - B32B 27/18: characterised by the use of special additives - B32B 27/308: {comprising acrylic (co)polymers} - B32B 27/32: comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} - B32B 2250/242: All polymers belonging to those covered by group B32B27/32 - B32B 2270/00: Resin or rubber layer containing a blend of at least two different polymers - B32B 2307/30: having particular thermal properties - B32B 2307/31: Heat sealable - B32B 2307/408: Matt, dull surface - B32B 2307/518: bi-axially - B32B 2307/7244: Oxygen barrier - B32B 2307/748: Releasability - B32B 2439/70: Food packaging - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM ## Abstract A heat-sealable polymer-based multilayer film for peelably and releasably packaging pasty or fatty foods comprising a polymer-based core layer having a food-facing side and an exterior-facing side, a peelable layer on the food-facing side of the core layer, the peelable layer having a food-facing side and a core-facing side, and the peelable layer containing a peeling agent, and an interior skin layer on the food-facing side of the peelable layer, the interior skin layer having a food-facing side and a core-facing side. The core layer contains a release agent for diffusion toward the interior skin layer, and the release agent is present in the core layer in a quantity which is greater than the saturation capacity of peeling agent in the peelable layer for the release agent. ## Claims ### Claim 1 A heat-sealable polymer-based multilayer film for peelably and releasably packaging pasty or fatty foods comprising: a polymer-based core layer having a food-facing side and an exterior-facing side; a peelable layer on the food-facing side of the core layer, the peelable layer having a food-facing side and a core-facing side, and the peelable layer containing a peeling agent; and an interior skin layer on the food-facing side of the peelable layer, the interior skin layer having a food-facing side and a core-facing side; wherein the core layer contains a release agent for diffusion toward the interior skin layer; wherein the peeling agent in the peelable layer has a saturation capacity for the release agent and the release agent is present in the core layer in a quantity which is greater than said saturation capacity; and wherein the core layer contains the release agent in a concentration (Pc) which is greater than 0.5×Tp×(Pp/Tc), wherein Tp is the thickness of the peelable layer, Pp is the concentration of peeling agent in the peelable layer, and Tc is the thickness of the core layer. ### Claim 2 (depends on 1) The multilayer film of claim 1 wherein the release agent is a polyol ester and the peeling agent is an ethylene copolymer. ### Claim 3 (depends on 1) The multilayer film of claim 1 wherein a concentration of release agent in the core layer is determined as a function of the thickness of the core layer, the thickness of the peelable layer, and the concentration of peeling agent in the peelable layer. ### Claim 4 (depends on 1) The multilayer film of claim 1 wherein the concentration (Pc) of release agent in the core layer is less than 1.5×Tp×(Pp/Tc). ### Claim 5 (depends on 2) The multilayer film of claim 2 wherein the release agent polyol ester is selected from the group consisting of glycerol monostearate, glycerol monobehenate, and glycerol monooleate. ### Claim 6 (depends on 2) The multilayer film of claim 2 wherein the peeling agent ethylene copolymer is selected from the group consisting of ethylene acrylic acid copolymer, ethylene methacrylate, and ethylene ethyl acrylate. ### Claim 7 (depends on 1) The multilayer film of claim 1 wherein the thickness of the core layer is between about 10 and about 80 μm. ### Claim 8 (depends on 7) The multilayer film of claim 7 wherein the thickness of the core layer is between about 15 and about 40 μm. ### Claim 9 (depends on 1) The multilayer film of claim 1 wherein the thickness of the peelable layer is between about 0.25 and about 6 μm. ### Claim 10 (depends on 7) The multilayer film of claim 7 wherein the thickness of the peelable layer is between about 0.5 and about 3 μm. ### Claim 11 (depends on 1) The multilayer film of claim 1 wherein the thickness of the interior skin layer is between about 0.25 and about 6 μm. ### Claim 12 (depends on 1) The multilayer film of claim 1 wherein: the concentration (Pc) of release agent in the core layer is less than 1.5×Tp×(Pp/Tc); the release agent is a polyol ester; the peeling agent is an ethylene copolymer; the thickness of the core layer is between about 10 and about 80 μm; the thickness of the peelable layer is between about 0.25 and about 6 μm; and the thickness of the interior skin layer is between about 0.25 and about 6 μm. ### Claim 13 (depends on 1) The multilayer film of claim 1 wherein the film further comprises: an exterior skin layer on the exterior-facing side of the core layer. ### Claim 14 (depends on 1) The multilayer film of claim 1 wherein the film further comprises: an oxygen barrier layer on the exterior-facing side of the core layer. ### Claim 15 (depends on 1) The multilayer film of claim 1 wherein the film is a biaxially oriented polypropylene (BOPP) film. ### Claim 16 (depends on 1) The multilayer film of claim 1 wherein the interior skin layer has a low seal initiation temperature. ### Claim 17 (depends on 13) The multilayer film of claim 13 wherein the exterior skin layer has a low seal initiation temperature. ### Claim 18 (depends on 1) The multilayer film of claim 1 wherein the interior skin layer has matte appearance. ### Claim 19 (depends on 1) The multilayer film of claim 1 wherein the exterior skin layer has matte appearance.