# US 2013/0157032 A1 · Multi-Layered Film Containing a Biopolymer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0157032 A1 - Document ID: US20130157032A1 - Status: Published application - Kind: A1 - Application number: 13/330,820 - Filed: 2011-12-20 - Published: 2013-06-20 - Earliest claimed: 2011-12-20 - Assignees: Kimberly-Clark Worldwide, Inc. - Inventors: James H. Wang; Gregory J. Wideman; Brent M. Thompson - Web page: https://patentgrep.com/patent/US20130157032A1 ## CPC - B32B 27/08: of synthetic resin - B32B 27/32: comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} - B32B 27/36: comprising polyesters - B32B 2250/02: 2 layers - B32B 2250/03: 3 layers - B32B 2250/24: All layers being polymeric - B32B 2270/00: Resin or rubber layer containing a blend of at least two different polymers - B32B 2307/7163: Biodegradable - 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 film that contains a core layer positioned adjacent to an outer layer is provided. The core layer contains a relatively high percentage of thermoplastic biopolymers that are both biodegradable and renewable. Despite being biodegradable and renewable, many biopolymers tend to be relatively stiff in nature. The present inventors have discovered, however, that through selective control over the components in the core and outer layers, a film can be readily formed having good mechanical properties. Among other things, this is accomplished by blending the biopolymer in the core layer with a polyolefin. A polyolefin is also employed in the outer layer. In addition to providing functionality to the film (e.g., heat sealing, printing, etc.), the polyolefin-containing outer layer also helps counteract the stiffness of the biopolymer in the core layer, and helps improve processability, stiffness, and ductility. ## Claims ### Claim 1 A multi-layered film having a thickness of about 250 micrometers or less, the film comprising: a core layer that constitutes from about 20% to about 90% of the thickness of the film, wherein the core layer contains from about 10 wt. % to about 95 wt. % of at least one thermoplastic biopolymer and from about 5 wt. % to about 90 wt. % of at least one polyolefin; and an outer layer positioned adjacent to the core layer, wherein the outer layer contains about 50 wt. % or more of at least one polyolefin. ### Claim 2 (depends on 1) The multi-layered film of claim 1, wherein the core layer contains from about 50 wt. % to about 90 wt. % of at least one thermoplastic biopolymer and from about 10 wt. % to about 50 wt. % of at least one polyolefin. ### Claim 3 (depends on 1) The multi-layered film of claim 1, wherein the thermoplastic biopolymer is an agro-derived or bio-based aliphatic polyester. ### Claim 4 (depends on 3) The multi-layered film of claim 3, wherein the aliphatic polyester is a polylactic acid, polyhydroxyalkanoate, polyalkylene succinate, or a combination thereof. ### Claim 5 (depends on 3) The multi-layered film of claim 3, wherein the agro-derived aliphatic polyester has a glass transition temperature of about 0° C. or more. ### Claim 6 (depends on 1) The multi-layered film of claim 1, wherein the polyolefin of the core layer, the outer layer, or both is a copolymer of an α-olefin and ethylene. ### Claim 7 (depends on 1) The multi-layered film of claim 1, wherein the core layer is free of a compatibilizer, plasticizer, or both. ### Claim 8 (depends on 1) The multi-layered film of claim 1, wherein polyolefins constitute the entire polymer content of the outer layer. ### Claim 9 (depends on 1) The multi-layered film of claim 1, wherein the outer layer further contains about 50 wt. % or less of at least one additional polymer. ### Claim 10 (depends on 9) The multi-layered film of claim 9, wherein the additional polymer is a starch polymer. ### Claim 11 (depends on 1) The multi-layered film of claim 1, wherein the core layer constitutes from about 45% to about 75% of the thickness of the film. ### Claim 12 (depends on 1) The multi-layered film of claim 1, wherein the film exhibits a percent strain at break in the machine direction of about 200% or more and a percent strain at break in the cross-machine direction of about 300% or more. ### Claim 13 (depends on 1) The multi-layered film of claim 1, wherein the film exhibits a modulus of elasticity in the machine direction of from about 50 to about 600 Megapascals and a modulus of elasticity in the cross-machine direction of from about 50 to about 600 Megapascals. ### Claim 14 A multi-layered film having a thickness of about 250 micrometers or less, the film comprising: a first outer layer that contains about 50 wt. % or more of at least one polyolefin; a second outer layer that contains about 50 wt % or more of at least one polyolefin; a core layer that is positioned between the first and second outer layers and constitutes from about 20% to about 90% of the thickness of the film, wherein the core layer contains from about 10 wt. % to about 95 wt. % of at least one thermoplastic biopolymer and from about 5 wt. % to about 90 wt. % of at least one polyolefin. ### Claim 15 (depends on 14) The multi-layered film of claim 14, wherein the thermoplastic biopolymer is an agro-derived or bio-based aliphatic polyester. ### Claim 16 (depends on 15) The multi-layered film of claim 15, wherein the aliphatic polyester is a polylactic acid, polyhydroxyalkanoate, polyalkylene succinate, or a combination thereof. ### Claim 17 (depends on 15) The multi-layered film of claim 15, wherein the agro-derived aliphatic polyester has a glass transition temperature of about 0° C. or more. ### Claim 18 (depends on 14) The multi-layered film of claim 14, wherein the polyolefin of the core layer, the first outer layer, the second outer layer, or a combination thereof is a copolymer of an α-olefin and ethylene. ### Claim 19 (depends on 14) The multi-layered film of claim 14, wherein the film exhibits a percent strain at break in the machine direction of about 200% or more and a percent strain at break in the cross-machine direction of about 300% or more. ### Claim 20 (depends on 14) The multi-layered film of claim 14, wherein the film exhibits a modulus of elasticity in the machine direction of from about 50 to about 600 Megapascals and a modulus of elasticity in the cross-machine direction of from about 50 to about 600 Megapascals.