A sizer for cooling an extrudate includes a core and a housing. The core includes an extrusion channel which accommodates the extrudate, a core cooling channel, and a core vacuum channel in fluid communication with said extrusion channel. The housing includes a housing cooling channel, a housing vacuum channel, a cooling intake, and a cooling exhaust. The housing cooling and vacuum channels having curved segments. The cooling intake and exhaust being in fluid communication with said housing cooling channel.

The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Significant increases in production speeds are achieved with improved film quality over an increased range of tubular film sizes, down to a minimum size which occurs when operating at zero internal to molten film tube pressure.

A blown film line and process for making blown film, including an annular extrusion or coextrusion die, a plurality of nip rollers at a location remote from the annular die, a blown film bubble extruding from the annular die and traveling toward the nip rollers along a traveling path, an air cooling apparatus in the vicinity of the annular die, and a water cooling apparatus located downstream from the air cooling apparatus along the traveling path. The water cooling apparatus includes a wet porous material in direct contact with the blown film bubble and surrounding an outer circumference of the blown film bubble. The wet porous material continuously wipes the blown film bubble with water as the blown film bubble moves along the traveling path.

The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas (i) in a path opposing the flow of the molten film tube toward a first exit gap and (ii) in a path with the flow of the molten film tube toward a second exit gap. A minimum gap between the divergent cooling interface and the molten film tube occurs at the first exit gap and/or the second exit gap. Advantageously, the divergent cooling interface is provided with one or more compound angles to maximize stability and cooling efficiency. Additionally, multiple cooling elements can preferably be arranged in a stackable configuration to achieve higher throughput rates. Operation is characterized by improved film holding forces without the presence of high noise levels or detrimental vibration, flutter, and drag. Additionally, employing simplified single air delivery channels, and a stackable design, significantly reduces complexity and manufacturing costs.

The present invention provides a multilayer packaging film characterized by an improved sealability even through contamination with excellent shrinkability good optics and strength without using internal layers of stiff resins and cross-linking, to flexible containers made therefrom, such as bags, pouches and the like, useful for packaging articles, in particular food items.

The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Additionally, at least one cooling element is provided, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas.

A film molding device includes: a cooling unit that cools a molding material discharged from a mold; and a rectifying unit that rectifies cooling air blown out from the cooling unit. The rectifying unit includes a suction portion that suctions the cooling air.

A packaged product has a product surrounded by a vacuum skin package. The vacuum skin package has a support member and an implosion-resistant thermoplastic top web. The top web conforms with both the upper surface of the product, and an uncovered portion of the upper surface of the support member. The thermoplastic top web comprises an ethylene/α-olefin copolymer in an amount of from 55 wt % to 85 wt %, based on total weight of top web, and/or a blend of ethylene/α-olefin copolymer and cyclic olefin copolymer. Also disclosed is a vacuum skin package containing the implosion-resistant top web.

A film forming apparatus includes a die device which extrudes a molten resin in a tube shape to form a film, a measurement unit which measures a thickness profile of a film in a circumferential direction, a plurality of adjustment portions which change the thickness profile of the film, and a controller which controls the plurality of adjustment portions such that the thickness profile approaches a target thickness profile. The controller changes the target thickness profile based on the measured thickness profile.

An air ring comprises a circular plenum in fluid communication with a source of pressurized air. An upper and lower annular lips are in fluid communication with the plenum through upper and lower channels and are arranged to supply air to the blown film bubble. A plurality of vanes are disposed in the upper channel and extend radially inwardly from the plenum to the upper annular lip. The vanes divide the upper channel into a plurality of radially extending channel segments. Each vane has a selected length and a distal end proximal the upper annular lip, the distal end being spaced from the upper annular lip no greater than about 20% of the length of the vanes. A powered plunger extends between the vanes of each of the channel segments to vary the cross-sectional area of the channel segments.