The Dow Chemical Company

Robert A Luecke

Gordon E Gould

Susan E Dollinger

James E Holton

Oscar F Johnson

Leandra P Martin

Paul M Curtin

Disclosed is a process for preparing a biaxially oriented substantially non-shrinkable film comprising coextruding a multilayered film comprising a first and second outer layers of resinous thermoplastic material and a barrier layer of a resinous copolymer of vinylidene chloride and an alkyl acrylate, and biaxially draw-tentering the film at a temperature within about 10.degree. C. of the melting point of the copolymer and less than the melting point of the thermoplastic materials of the outer layers.

Process of biaxially orienting coextruded barrier films of

Disclosed are biaxially oriented, coextruded multilayer barrier films wherein a substantial degree of oxygen impermeability is retained after orientation. The barrier layer of the films comprise a copolymer of vinylidene chloride and an alkyl acrylate, wherein the copolymer has a melting point about equal to or less than the melting point of the thermoplastic material comprising the outer layers of the film and has an oxygen permeability of less than 0.25 cc-mil/100 sq. in.-atm-day based upon the thickness of the barrier layer. Further disclosed are biaxially oriented nonshrinkable multilayer barrier films having barrier layers of a copolymer of vinylidene chloride and from more than 6 to about 10 weight percent methyl acrylate. Further disclosed is a process for making the biaxially oriented, coextruded barrier films.

Oriented coextruded barrier films of polyvinylidene chloride copolymers

A process and apparatus are disclosed for reducing the carbonization of a thermally degradable barrier material during the extrusion of a multilayer laminate. A core extrudate of barrier material is extruded with a core extruder. A preencapsulation means is provided adjacent the downstream end of the core extruder. The core extrudate is joined with a preencapsular extrudate in the preencapsulation means in a coaxial relation wherein the preencapsular extrudate is disposed radially outwardly of the core extrudate. The preencapsulated core extrudate is then directed to a feed block and coextrusion die for incorporation in the coextruded multilayer film.

Extrusion apparatus and process for production of multilayer film

A filtering system for use in coextrusion apparatus, and particularly for removing carbon particles from a core extrudate of thermally degradable barrier material which has been preencapsulated with a preencapsular material. The filter includes a casing and a frame mounted to the casing. A coarse filter screen through which the component streams can flow is also provided. The coarse filter screen is mounted to the frame and is composed of a web of woven strands having a sufficiently small diameter so as to permit the preencapsulated core extrudate to pass through and emerge from the coarse filter screen without substantial mixing of the barrier material and the preencapsular material. The fine filter screen is supported by the coarse filter screen upstream of the coarse filter screen.

Filtering system for use in coextrusion apparatus and method of use

A tubular film and method for making the film by extrusion provide a multi-layer film having a central layer of barrier material which overlaps itself by a substantial distance along a weld line. The film includes inner and outer adhesive layers positioned on opposite sides of the central barrier layer, which adhesive layers completely encapsulated the central barrier layer. Finally, the film includes inner and outer surface layers. The inner surface layer is positioned within the inner adhesive layer, and the outer surface layer is positioned outside the outer adhesive layer.

Tubular, multi-layer film and method of making

An improved process for making synthetic paper/film from a blend of polystyrene and polyethylene resins wherein titanium dioxide is employed as the sole inorganic filler and the film is given an oxidizing post-treatment, such as corona discharge or surface sulfonation. The film so-prepared has improved adhesion to photographic gel emulsions.

Process for the manufacture of synthetic paper and the product thereof

A spirally wound container for leavened dough and other products which is opened by side rupture. The container comprises a fiber board body having multiple thermoplastic film plies. An inner transparent ply of film adheres to the surface of the fiber board spirally wound can body and is rupturable therewith. An outer ply of film forms a label cover for the container and is strippable prior to opening of the container. After the label ply is stripped from the container, the transparent inner ply permits reading of graphics printed on the fiber body of the can. The inner film ply strengthens the body ply and acts as a moisture barrier.

Growing community of inventors

Newark, OH, United States of America

Robert A Luecke