A method includes applying a stress to a polymer thin film to stretch the polymer thin film along a first in-plane direction, and subsequently applying a stress to the polymer thin film to stretch the polymer thin film along a second in-plane direction orthogonal to the first in-plane direction to form an ultra-high modulus polymer thin film. Calendaring or hot pressing of the ultra-high modulus polymer thin film may improve its optical and/or thermal properties.

A moisture vapor permeable, water impermeable composite sheet material is provided which is suitable for use as a housewrap material, and is also useful for other applications such as tarpaulins, or as covers for automobile, boats, patio furniture or the like. The composite sheet material includes a nonwoven substrate and an extrusion-coated polyolefin film layer overlying one surface of the substrate. The nonwoven substrate is comprised of polymeric fibers randomly disposed and bonded to one another to form a high tenacity nonwoven web. The nonwoven substrate has a grab tensile strength of at least 178 Newtons (40 pounds) in at least one of the machine direction (MD) or the cross-machine direction (CD). The extrusion coated polyolefin film layer is intimately bonded to the nonwoven substrate. The film layer has micropores formed therein to impart to the composite sheet material a moisture vapor transmission rate (MVTR) of at least 35 g/m.sup.2/24 hr. at 50% relative humidity and 23° C. and a hydrostatic head of at least 55 cm. In one embodiment, the nonwoven substrate comprises a spunbonded nonwoven fabric formed of randomly disposed substantially continuous polypropylene filaments. The spunbonded nonwoven fabric is an area bonded fabric in which the filaments are bonded to one another throughout the fabric at locations where the randomly disposed filaments overlie or cross one another.

A female loop portion for a hook and loop self-adhesive, comprising a film (1) made of at least one thermoplastic and a plurality of filaments (2) which are separate from one another and attached to one of the surfaces of the film, each filament comprising a series of fastening sections (15) and a series of loop sections (4) alternating with the fastening sections, the filaments being attached to the film along the fastening sections while the loop sections are at a distance from the film so as to form loops, and characterized in that a cross-sectional area of one loop section of a filament is less than a cross-sectional area of one fastening section of said one filament.

A female loop portion for a hook and loop self-adhesive, comprising a film (1) made of at least one thermoplastic and a plurality of filaments (2) which are separate from one another and attached to one of the surfaces of the film, each filament comprising a series of fastening sections (15) and a series of loop sections (4) alternating with the fastening sections, the filaments being attached to the film along the fastening sections while the loop sections are at a distance from the film so as to form loops, and characterized in that a cross-sectional area of one loop section of a filament is less than a cross-sectional area of one fastening section of said one filament.

The invention relates to a method for adapting at least one winding parameter of a winding device during winding of a film web on a winding core, having the following steps:—conveying of the film web along a measuring path between a first driven roll and a second driven roll—increasing of the web tension of the film web between the first roll and the second roll—continuous detecting of the drive parameters of the first roll and of the second roll at least in the form of the torque and the circumferential speed,—determining of a stress-strain diagram from the detected drive parameters—adapting of at least one winding parameter of the winding device on the basis of the determined stress-strain diagram in order to achieve a defined elongation of the film web during winding on the winding core.

A multilayer film having Machine Direction Orientation (MDO) is prepared by first co-extruding a multilayer film, then stretching the multilayer film in the machine direction at a temperature lower than the melting point of the polyethylene resin that is used to prepare the film. At least one layer of the film is a first polyethylene composition having a density of from about 0.94 to about 0.97 g/cc and at least one second layer is prepared from a polyethylene composition having a lower density than the first polyethylene composition. This disclosure enables the manufacture of films having outstanding barrier properties (low Water Vapor Transmission Rate, WVTR, and low Oxygen Transmission Rate, OTR) and good physical properties.

A multilayer film having Machine Direction Orientation (MDO) is prepared by first co-extruding a multilayer film, then stretching the multilayer film in the machine direction at a temperature lower than the melting point of the polyethylene resin that is used to prepare the film. At least one layer of the film is a first polyethylene composition having a density of from about 0.94 to about 0.97 g/cc and at least one second layer is prepared from a polyethylene composition having a lower density than the first polyethylene composition. This disclosure enables the manufacture of films having outstanding barrier properties (low Water Vapor Transmission Rate, WVTR, and low Oxygen Transmission Rate, OTR) and good physical properties.

An UHMWPE film having a tensile strength of at least 2.0 GPa, a tensile energy to break of at least 30 J/g, an Mw of at least 500 000 gram/mole, and a Mw/Mn ratio of at most 6, and a film width of at least 5 mm. The film may be manufactured via a process which comprises subjecting a starting UHMWPE with a weight average molecular weight of at least 500 000 gram/mole, an elastic shear modulus determined directly after melting at 160° C. of at most 1.4 MPa, and a Mw/Mn ratio of at most 6 to a compacting step and a stretching step under such conditions that at no point during the processing of the polymer its temperature is raised to a value above its melting point. The film may be used as starting material in any applications where high tensile strength and high energy to break are important. Suitable applications include ballistic applications, ropes, cables, nets, fabrics, and protective applications.

A method of producing an optical panel assembly including the polarizing film in a continuous manner by laminating a polarizing film to a surface of a rectangular-shaped optical panel, is disclosed. The polarizing film is formed by performing a step of subjecting a laminate including a continuous web of a thermoplastic resin substrate and a PVA type resin layer formed on the substrate, to a 2-stage stretching consisting of a preliminary in-air stretching and an in-boric-acid-solution stretching, to reduce a thickness of the PVA type resin layer to 10 μm or less, and a step of causing a dichroic material to be absorbed in the PVA type resin layer.

A transverse cutting system for a machine for the production of plastic film includes a supporting structure carrying a cutting unit, which are moved between a rest position away from a path of a plastic film being wound and an operating position along the path of the plastic film; a rotating support carrying a hot wire; a rotating cap, associated to an idle roller and arranged transversally to the path of the plastic film that is moving forwards, and an actuator, which controls the rotation of the rotating support carrying the rotating cap and causes the rotating cap to interfere with the plastic film before the hot wire also interferes with said plastic film. The same plastic film, owing to the friction force generated by the rotating cap, entrains it with it, causing the rotating cap to equalize the linear velocity of the plastic film.