Abstract: A multilayer plastic film or sheet having a series of component layers and optional bonding layers tying said component layers together is provided. The multilayer film or sheet comprises a central barrier layer comprising first and second layers of polyvinylidene chloride polymer bonded together with a tie or bonding layer, an outer layer adjacent to an outer side of the first PVDC layer, and a sealant layer adjacent to an outer side of the second PVDC layer.

Abstract: A multilayer plastic film or sheet having a series of component layers and optional bonding layers tying said component layers together is provided. The multilayer film or sheet comprises a central barrier layer comprising first and second layers of polyvinylidene chloride polymer bonded together with a tie or bonding layer, an outer layer adjacent to an outer side of the first PVDC layer, and a sealant layer adjacent to an outer side of the second PVDC layer.

Abstract: A multi-layer tubular film is co-extruded and cooled to form a first bubble, then collapsed, preheated and blown into a second bubble. The second bubble is further heated from outside to produce a decreasing temperature gradient from the outside surface of the film to the inside surface of the film. The outside surface of the film is hotter than the inside surface of the film and the inside surface of the f film is hot enough for re-blowing but sufficiently cool to avoid blocking. The film is then collapsed, blown into a third bubble and cooled to produce biaxially-oriented film, which is then collapsed, blown into a fourth bubble, heated and then cooled film to relieve stress and impart desired shrink properties to the film to produce ship-stable biaxially-oriented film.

Abstract: A multilayer film is herein provided. The film, which is useful for packaging, comprises: —a core barrier layer having an outer side and an inner side, said core barrier layer comprising one or more barrier polymers that exhibit moisture and/or oxygen barrier properties, wherein said barrier polymer is optionally coupled to a slow crystallizing polyamide or a polymer blend thereof; —an outer layer bonded to the outer side of the core barrier layer comprising a rigid polymer having an inherent viscosity (IV) in the range of about 3.2 to 4.7, wherein the outer layer optionally comprises slow crystallizing polymer (SCP) or a polymer blend thereof; and —a sealant layer bonded to the inner side of the core barrier layer comprising one or more polyolefins sufficient to provide a seal.

Abstract: A novel multilayer plastic film is provided comprising a series of component layers and optionally bonding layers to tie said component layers together, said component layers comprising: a central oxygen barrier layer, a first polymeric barrier layer on a first side of said central oxygen barrier layer, a second polymeric barrier layer on a second side of said central oxygen barrier layer, an outer layer adjacent the first polymeric barrier layer for providing mechanical strength, and a sealant layer adjacent the second polymeric barrier layer. At least one layer comprises two different polymers.

Abstract: A body member for an extrusion die for multilayer film has a passage-forming surface and an open feed channel formed in the passage-forming surface. The feed channel continuously decreases in depth from the feed channel inlet, and the feed channel is of substantially constant-width substantially rectangular cross-section along substantially its entire extent. Corners of the feed channel may be slightly rounded. Substantially constant-width feed channels of substantially rectangular cross-section may be used in blown film applications, in which case the feed channel extends in a spiral from the feed channel inlet, and in cast film applications, in which case the feed channel extends substantially linearly from the feed channel inlet. Dies can be assembled by arranging two body members with their respective passage-forming surfaces opposed to one another.

Abstract: Packaging containing a PVDC barrier layer is manufactured without any significant orientation, with the result that the PVDC harrier layer remains flexible at significantly greater thicknesses than when it is oriented. This increased thickness compensates for the reduced barrier properties resulting from less crystallinity of the PVDC, and hence multilayer plastic tubing can be manufactured in which PVDC is used as a barrier layer instead of aluminum.

Abstract: Bags are formed from reclaimed plastic material. Each bag comprises two opposed sheet sections formed substantially entirely of a first polymer class, but also containing impurity particles of a different polymer class. The sheet sections comprise at least two distinct independent layers, with each layer in each sheet section being surface bonded to each adjacent layer in that sheet section. Although discontinuities in each layer resulting from the impurity particles create weak areas and in some cases apertures, the weakened portions of each layer are reinforced by portions of the other layer that are not weakened, since there is a minute likelihood that an impurity particle in one layer will be precisely co-located with an impurity particle in an adjacent layer. Thus, each layer reinforces the other layer to maintain structural integrity of the sheet section and of the bag. Methods for forming such bags are also described.

Abstract: Apparatus for controlled shrinking of molten plastic sheet material comprises a series of parallel cylindrical rollers for moving the plastic sheet material from a first position to a second position. At least one heater is aligned with the rollers for maintaining the plastic sheet material in a molten state while the rollers move the plastic sheet material, and a drive mechanism rotates the rollers so that the tangential speed of the rollers progressively decreases from the first position toward the second position. As a result of the progressive decrease in tangential speed of the rollers, the speed of the plastic sheet material is progressively reduced as the plastic sheet material approaches the second position, so that portions of the plastic sheet material closer to the second position move toward the second position more slowly than portions of the plastic sheet material further from the second position.

Abstract: A method of producing a multilayer plastic film from resin starting material includes irradiating a batch of plastic resin material and using irradiated resin from the batch to produce at least one layer of a multilayer plastic film.

Abstract: Bags are formed from reclaimed plastic material. Each bag comprises two opposed sheet sections formed substantially entirely of a first plastic type, but also containing impurity particles of a different plastic type. The sheet sections comprise at least two distinct independent layers, with each layer in each sheet section being surface bonded to each adjacent layer in that sheet section. Although discontinuities in each layer resulting from the impurity particles create weak areas and in some cases apertures, the weakened portions of each layer are reinforced by portions of the other layer that are not weakened, since there is a minute likelihood that an impurity particle in one layer will be precisely co-located with an impurity particle in an adjacent layer. Thus, each layer reinforces the other layer to maintain structural integrity of the sheet section and of the bag. Methods for forming such bags are also described.

Abstract: A method of producing a multilayer plastic film from resin starting material includes irradiating a batch of plastic resin material and using irradiated resin from the batch to produce at least one layer of a multilayer plastic film.

Abstract: Stretch plastic film is formed by extruding suitable plastic material from an annular die as a tubular film, forming the extruded film into a bubble with air entrapped therein by collapsing the tubular film at a predetermined distance from the annular die, causing the temperature of the tubular film when collapsed to be sufficiently high to cause opposite sides of the collapsed film to become bonded together to form a blocked two layer film, and stretching the blocked two layer film to reduce its thickness.

Abstract: A multilayer plastic film has a series of component layers and bonding layers bonding said component layers together, the component layers including an inner hydrolysed ethylene vinyl acetate copolymer (EVOH) layer, an adjacent polyvinylidene chloride (PVDC) layer, and outer layers comprising a polyolefin homopolymer, copolymer or ionomer.

Abstract: Stretch plastic film is formed by extruding suitable plastic material from an annular die as a tubular film, forming extruded film into a bubble with air entrapped therein by collapsing the tubular film at a predetermined distance from the annular die, and causing the temperature of the tubular film when collapsed to be sufficiently high to cause opposite sides of the collapsed film to become bonded together to form a single layer of film.

Abstract: A multilayer plastic film has at least two inner polyvinylidene chloride (PVDC) layers, outer layers comprising a polyolefin homopolymer, copolymer or ionomer, and bonding layers between the PVDC layers and between the PVDC layers and the outer layers.