American National Can Company

American Can Company

Other

Bemis Company, Inc.

Baxter Travenol Laboratories, Inc.

Pechiney Emballage Flexible Europe

American National Can

Roger P Genske

Yong J Kim

Frank T Bauer

Russell P Gehrke

William F Ossian

Dennis E Kester

Ronald C Christensen

Robert J Blemberg

Richard E Johnson

Leonard F Czuba

R Daniel Webster

Suzanne E Schaefer

Erin M Duffy

Roy A Bubel

The embodiments of the present invention relate to multilayer thermoplastic structures having improved sealability and tearability. More specifically, the present invention relates to a multilayer heat sealant structure having at least three layers that may be coextrusion coated or otherwise laminated to a substrate, such as metallized polymeric material, foil, or other substrates.

Multilayer heat sealant structures, packages and methods of making the same

A multilayer film structure having at least two layers wherein the first layer comprises poly(ethylene) having a density range from about 0.93 g/cc to 0.97 g/cc; and a second layer comprising poly(ethylene) having a density range from 0.89 g/cc to 0.93 g/cc wherein the second layer is capable of forming a heat seal. The multilayer film structure is capable of being laminated to another film structure or a packaging film component. The packages of the present invention are useful for the packaging of flowable materials.

Multilayer film structures having improved seal and tear properties

Multi-layer films having an outer sealant layer which readily delaminates from the adjacent sealant layer are disclosed. For retort applications, preferably one of the outer or adjacent sealant layers is comprised of a majority of ethylene moieties and the other of the outer or adjacent sealant layers is comprised of a majority of propylene moieties. The film is especially well-suited for use as a lidstock sealed to a container, such as a tray.

Easy peel film structure especially for retortable lidstock

Compositions of matter, sheet material, and packages made therefrom. Novel compositions of polypropylene and high density polyethylene are useful as sealant materials for flexible sheet material structures wherein the sheet material is sealable to a preformed container, to form a lid therefor, and is peelable therefrom, with cohesive failure of the sealant layer in the area of the formed seal. The novel sealant layer compositions provided for package closure and sealing which is capable of withstanding retort conditions while maintaining the integrity of the package closure and seal. Concurrently the lid is readily peeled from the package to provide access to the interior of the package. The peelability comprises cohesive failure of the sealant material in a novel blend of a polypropylene polymer with an ethylene polymer having a density of at least 0.940. The novel sealant materials of the invention can be used on a variety of multiple layer sheet material substructures, and particularly those providing barrier properties to food type packaging: especially barrier to the transmission of oxygen and moisture. Typical barrier materials are metal foil, vinylidene chloride copolymer, vinyl alcohol copolymer, olefin polymers and copolymers, and combinations of the above materials.

Peelable packaging and sheet materials and compositions for use therein

A multiple layer sheet material comprising a first layer 12 of vinylidene chloride copolymer having a first softening temperature. A second polymeric sealant layer 14 has a second softening temperature no more than about 50.degree. C. less than the first softening temperature. An optional third layer 16 between the first and second layers has a third softening temperature greater than either of the first and second softening temperatures and comprises a polyethylene terephthalate composition. A fourth polymeric layer 18 has a fourth softening temperature greater than the first and second softening temperatures. The first layer is positioned between the third and fourth layers. A fifth impact layer 20 is positioned between layers 14 and 16. The composition of the impact layer 20 comprises, as a first component, a base polymer drawn from the same family of polymers as a major polymeric component of the second sealant layer, and, as a second component, a polymeric composition providing elastomeric properties to the impact layer and increased shock tolerance to the multiple layer sheet material. The disclosure also teaches the use of the sheet materials in fabrication of packages and teaches methods of fabricating both the sheet materials and the packages.

Multiple layer packaging sheet material

Packaging sheet materials 10 and packages having improved impact/shock tolerance as measured in a slope drop test. The sheet materials comprise an impact layer 12 of a blend of polypropylene and a polymer providing elastomeric properties between a sealant substructure 14 and a substrate substructure 16.

Polymeric film which is a blend of about 10% to 65% by weight polyisobutylene and conversely about 90% to 35% by weight of polypropylene copolymer. The polypropylene is preferably a copolymer having about 70 to about 98 mole percent propylene moieties and conversely about 30 to about 2 mole percent ethylene moieties. Preferred films have a blend composition of 20% to 40% by weight polyisobutylene and 80% to 60% by weight polypropylene copolymer. It is also preferred that the polypropylene copolymer is 92 to 98 mole percent propylene moieties and conversely 2 to 8 mole percent ethylene moieties.

Films using blends of polypropylene and polyisobutylene

Novel films are disclosed which contain blends of ethylene-based copolymers or other elastomers with polypropylene and polyethylene. Typical films have two-five layers wherein at least one layer is a blend of high density polyethylene with an ethylene-based copolymer or another elastomer and has additional layers of polypropylene blended with an ethylene-based copolymer or another elastomer.

Films of polypropylene blends and polyethylene blends and articles made

This invention teaches using blends of polyisobutylene and polypropylene copolymer in the formation of single layer films and multiple layer sheet materials. The films and sheet materials are useful as flexible packaging materials. The multiple layer sheet materials may be entirely polymeric or may include layers having nonpolymeric components, such as metal. The blends of polyisobutylene and polypropylene copolymer unexpectedly have the capability of being extruded through a slot die to form a film having a functionally useful mixture of its components. Thus the invention further includes methods of forming film-like layers of the blends of polyisobutylene and polypropylene copolymer.

Sheet structures wherein the composition of one layer comprises a first component of a polypropylene, a second component of an ethylene-based copolymer, and a third component which provides some properties representative of elastomeric polymers. The invention further contemplates packages made from the sheet structures incorporating the recited compositions.

Multiple layer sheet structures and package

Compositions of matter, sheet material, and packages made therefrom. Novel compositions of polypropylene and high density polethylene are useful as sealant materials for flexible sheet material structures wherein the sheet material is sealable to a preformed container, to form a lid therefor, and is peelable therefrom, with cohesive failure of the sealant layer in the area of the formed seal. The novel sealant layer compositions provide for package closure and sealing which is capable of withstanding retort conditions while maintaining the integrity of the package closure and seal. Concurrently the lid is readily peeled from the package to provide access to the interior of the package. The peelability comprises cohesive failure of the sealant material in a novel blend of a polypropylene polymer with an ethylene polymer having a density of at least 0.940. The novel sealant materials of the invention can be used on a variety of multiple layer sheet material substructures, and particularly those providing barrier properties to food type packaging; especially barrier to the transmission of oxygen and moisture. Typical barrier materials are metal foil, vinylidene chloride copolymer, vinyl alcohol copolymer, olefin polymers and copolymers, and combinations of the above materials.

This invention teaches using blends of polyisobutylene and polypropylene copolymer in the formation of single layer films and multiple layer sheet materials. The films and sheet materials are useful as flexible packaging materials. The multiple layer sheet materials may be entirely polymeric or may include layers having non-polymeric components, such as metal. The blends of polyisobutylene and polypropylene copolymer unexpectedly have the capability of being extruded through a slot die to form a film having a functionally useful mixture of its components. Thus the invention further includes methods of forming film-like layers of the blends of polyisobutylene and polypropylene copolymer.

Growing community of inventors

Neenah, WI, United States of America

Roger P Genske