A machine for manufacturing pre-stretched extendable film rolls provides for a pre-stretch unit (10) of the film (F) and a wrapping unit (100) of the film in roll provided with a series of rolls around which the advancing film is partially wrapped; the pre-stretch unit (10) provides for, in sequence, at least a first pre-stretching roll (12), a pre-stretching auxiliary roll (13) acting against the first roll (12) with the interposition of the film, and a second pre-stretching roll (14) having a speed greater than the speed of the first roll (12) to carry out the pre-stretching of the film; the wrapping unit provides for a wrapping roll (104) for wrapping the pre-stretched film; the pre-stretch unit (10) further provides for a detensioning roll (17) arranged downstream said second pre-stretching roll (14) and having a speed less than said second pre-stretching roll (14) and greater than said wrapping roll (104), so as to obtain a first detensioning of the film after the pre-stretching operation and a second detensioning of the film before the wrapping operation. A high quality pre-stretched film is obtained by this machine.

The invention relates to a separating device (10) for separating a tubular flat material (1) having an actual tube width (1.1), comprising at least one longitudinal separating unit (20) for removing a first edge region (2) and a second edge region (3) of the flat material (1). The invention further relates to a separating method (100) for separating a tubular flat material and to a system (70) having a separating device (10).

A sheet product package and method of making discrete plastic sheets includes a package enclosure with a dispensing opening structure and a plurality of discrete plastic sheets arranged in a stack. The plurality of discrete plastic sheets are disposed within the package enclosure, and each of the plurality of discrete plastic sheets is electrostatically charged. In the method of making the dispensable plastic sheets, electrostatically charged discrete plastic sheets are formed and arranged in a stack. The method may include forming a continuous plastic film, cutting the continuous plastic film into discrete plastic sheets, and, after cutting, electrostatically charging the discrete plastic sheets.

A method accurately determines internal stress in a film roll and prevents defects in the film roll. A film winding device includes a take-up roller and a winding tension adjustment device. A calculation device uses a winding equation in which a winding tension function is explicitly expressed, the winding tension function expressing a winding tension as a function of a radius of a core. The winding tension adjustment device controls winding tension in accordance with a winding tension distribution function calculated by the calculation device.

A film dispenser includes a holding member including a first end and a second end joined to the first end, the holding member defining a longitudinal axis extending from the first end to the second end, the second end defining a brake portion and a slot defined by the brake portion, the slot including a first slot portion extending in a circumferential direction across a width of the brake portion and second and third slot portions extending across a length of the brake portion, the second and third slot portions distal from each other on opposing sides of the brake portion, the slot further including fourth and fifth slot portions angled with respect to the second and third slot portions, respectively, the fourth and fifth slot portions extending in a circumferential direction, the fourth and fifth slot portions of the slot intersecting the second and third slot portions, respectively.

Apparatus and methods for producing folded edges in a film in-process, and compositions of such film are provided. A method of folding edges includes: separating a first idler roll and a second idler roll by a first distance; positioning a plurality of folding guides between the first idler roll and the second idler roll; separating adjacent sections of film having a majority layer comprising a Ziegler Natta catalyzed linear low density polyethylene copolymer resin having molecules that inherently lack long chain branching, wherein a majority of said molecules are oriented in a substantially longitudinal direction due to an induced strain, and inducing two folds with each folding guide, thereby causing an edge of each section of film to turn under 180 and cling to a bottom surface of the section of film; and moving the adjacent sections of film from the folding guides to the second idler roll.

A machine for producing coils of prestretched extendible film has a prestretching unit (10) for prestretching the film (F) and a winding unit (100) for winding the film in a coil provided with a series of rollers around which the advancing film winds partially; the winding unit comprises a winding roller (104) in pressing contact against the coil (R) of the prestretched film in winding progress; to obtain coils of constant diameter and high winding quality the final contact position is varied of the winding roller (104) against the coil (R) according to the length of the wound film and according to the required diameter of coil.

A method for cutting at least an outermost film of rollstock across a width direction of a film, the rollstock formed by a film sheet rolled from base end to tip end, the method including: separation step of generating a gap between the inner peripheral film and the outer layer by separating first edge portion of the outer layer from the inner peripheral film in a radial direction of the rollstock, in a state where the outer layer is remained to be rolled as a part of the rollstock; step of displacing a portion of the outer layer defining the gap in a first width direction from the first edge portion to second edge portion in the width direction; and step of cutting the outer layer across the width direction during the displacement step, while the first cutter is moved from the first edge portion to the second edge portion.

A continuous motion induction sealer rotary die and vacuum conveyor operates by pulling film thorough a rotary die assembly comprising a die and anvil geared together to rotate against each other cutting film patches from the film and securing them to the anvil surface via a vacuum pressure. The anvil then continues rotating to deposit the film patches onto a vacuum conveyor releasing the anvil vacuum to facilitate the transfer. The vacuum conveyor then conveys the film patches to an induction seal head and directs air pressure under the patch to transfer it to the induction seal head which secures the film patch via vacuum pressure while transferring and sealing the film patch to a container.

Provided is a roll body capable of effectively suppressing the occurrence of a telescope phenomenon even if the ambient temperature during transportation and storage of the roll body becomes higher than that during production of the roll body. A roll body RB according to the present invention configured by winding a belt-shaped web around a winding core that thermally expands or contracts due to an influence of a surrounding environment is characterized in that a linear expansion coefficient of the web in a thickness direction is in a range of 60 to 150 times a linear expansion coefficient of the web in a longitudinal direction, and the winding core has a linear expansion coefficient in a range of 20?10.sup.?6/K to 100?10.sup.?6/K and a Young's modulus in a range of 0.2 GPa to 0.5 GPa.