JPH082755A - Continuously winding method for resin film - Google Patents

Abstract

PURPOSE:To provide a resin film continuously winding method without bending an end part film of a film roll by preventing protrusive deformation generated in an end face intermediate part of the resin film roll. CONSTITUTION:In a method of continuously winding a resin film to a winding core, the resin film is continuously wound by narrowing a supply film width in the initial stage of winding start one after another or intermittently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous winding method for a resin film such as a soft vinyl chloride resin which does not cause a bulge in the intermediate part of the end surface of a wound resin film roll.

[0002]

2. Description of the Related Art When a resin film is produced or when a preliminarily wound resin film is rewound, the resin film roll is generally wound around a core. For example, when a film is continuously produced from a soft vinyl chloride resin by a method such as a calendering method, it is usually trimmed to have a constant width and wound on a winding core to form a wound resin film roll. Further, when the wound resin film roll that has been preliminarily wound is adjusted to a desired film length, etc., it is rewound by the method of winding it on the winding core to obtain a new resin film roll. In this way, when the resin film is produced or rewound, the film is wound at a high speed to improve the production efficiency and while applying a certain tension to the film to smooth the outer peripheral surface of the wound resin film roll. This tension acts in the direction of contracting the resin film, and in the wound resin film roll, it changes into a winding tightening force in the winding core direction, and as a result, the intermediate portion of the film roll end face expands in the width direction due to compression deformation. Occurs.

That is, although the change in the film width near the core is small, the film is widened by the winding tightening force as the film is wound, and the winding tightening force becomes weaker as it approaches the outer circumference of the film roll. The change in width is small, and eventually the film roll is deformed into a convex state in which the end surface of the film roll bulges to the maximum at a position of 1/6 to 1/3 of the film laminated thickness from the winding core. The end film near the core of the part that is widened by the winding tightening force in the wound state and swells to the maximum has a drawback that it bends inward (core side), and the bending of this end film is This causes troubles such as film breakage when the film roll is unraveled, and causes quality abnormalities such as impairing the lay flatness (flatness) of the unraveled film.

As a measure for preventing these troubles and quality abnormalities, the tension at the time of winding the film is reduced, and the contraction force of the film is relaxed to reduce the bulge (deformation) of the end surface of the film roll due to the tightening of the film, and Although a method of preventing the end film from bending has been adopted, production efficiency decreases and air is easily trapped between the films to be wound due to the decrease in tension during film winding, and this air accumulation causes wrinkling. It was the cause. In order to eliminate this drawback, a large amount of labor has conventionally been spent on adjusting tension.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention have made earnest studies on a winding method in which the end surface of a resin film roll does not swell even when wound at a high speed. By winding on the core while trimming both ends sequentially or intermittently while narrowing, it is possible to prevent the convex deformation that occurs in the middle part of the end face of the film roll and the bending of the end film of the roll film, and to wind at high speed. They have found what they can do and have completed the present invention. That is, the object of the present invention is to
Another object of the present invention is to provide a continuous winding method for a resin film, which prevents convex deformation occurring in the middle portion of the end surface of the film roll and prevents the end film of the film roll from bending.

[0006]

SUMMARY OF THE INVENTION The gist of the present invention is to reduce the supply film width in the initial stage of the winding step successively or intermittently in a method of continuously winding a resin film around a winding core. It is a method of continuously winding a characteristic resin film. The present invention will be described in detail.

Examples of the resin film which is an essential constituent of the present invention include vinyl chloride resin film, vinylidene chloride resin film, polyethylene film, polypropylene film, ethylene-vinyl acetate copolymer film, polystyrene film and the like. However, in the present invention, the effect is particularly large in films such as flexible vinyl chloride resin, low density polyethylene, and ethylene-vinyl acetate copolymer film which are flexible.

Although these films may be manufactured by any molding method, they are usually manufactured by a calendering method, an extrusion molding method, an inflation molding method or the like. The method of the present invention is particularly effective when applied to a calendering method in which a soft resin can be formed into a film at high speed and a high-speed winder is attached. Further, the method of the present invention is effective even in the step of rewinding the once wound film roll to adjust the film length and winding shape and winding the film roll on another core. The method of the present invention is a method of continuously winding the film around the winding core when forming the film or rewinding the film as described above.

To carry out the method of the present invention, a pair of film trimming devices (trimming cutters) installed upstream of the winding machine for resin films continuously supplied from a film forming device or a film rewinding device are used. Wind it around the core at high speed while trimming. In the initial stage of winding, the supply film is wound by the trimming cutter while narrowing the width of the supply film sequentially or intermittently. The pair of trimming cutters are configured to move symmetrically. The film width to be wound may be gradually or intermittently narrowed by moving a pair of trimming cutters inward until the winding is completed. The movement of the trimming cutter may be stopped and the winding may be completed while maintaining the narrowed constant width.

The resin film roll wound by these methods has a shape in which the width of the resin film is gradually narrowed from the core toward the outer periphery, or the film near the core is widened by the winding tightening force. The resin film has a shape in which the width of the resin film maintains the same width from the core toward the outer circumference, or is wound so as to become gradually narrower from the middle toward the outer circumference. In addition, the initial stage at the beginning of winding in the method of the present invention refers to the time when the film is wound up from the core side of the film laminated thickness of the wound resin film roll to a range of at least 1/6, preferably 1/3. This value depends on the hardness of the resin film.

Further, in the method of the present invention, it is desirable to widen the pair of trimming cutters just before the completion of winding to widen the width of the resin film supplied to the film width at the beginning of winding.
By expanding the film width immediately before the completion of winding, it has the effect of protecting the wound resin film roll,
Preparations for rewinding to the next core are made possible to enable continuous winding work. Although the moving speed of the trimming cutter varies depending on the winding speed (tension), the film thickness, the film roll winding diameter, etc., the end face shape of the film roll wound in advance with a constant tension, film thickness, and winding diameter is wound. It is possible to easily control by storing in the trimming cutter moving device together with the relationship between the time from the start of taking and the amount of end face deformation. The control of the moving speed of the cutter is not limited to the above-described method, and for example, during continuous winding, the shape of the end face of the film roll is detected by a laser sensor so that the cutter has a predetermined shape stored in advance. May be moved.

[0012]

According to the method of the present invention, even when the film is continuously wound around the winding core at a high speed, the convex deformation due to the winding tightening force does not occur in the intermediate portion of the end surface of the film roll, which is caused by the deformation. It was possible to prevent the bending of the end film that had been used, the problem of film breakage at the time of unraveling was solved, and the lay flatness of the unraveling film was also good, which was necessary for adjusting the winding tightening force. No labor is required and production efficiency can be improved.

[0013]

EXAMPLES The method of the present invention will now be described in detail with reference to examples, but the present invention is not limited to the following examples without departing from the gist thereof.

EXAMPLE A soft vinyl chloride resin composition containing 100 parts by weight of a vinyl chloride resin and 50 parts by weight of a plasticizer was used, and a calendering device equipped with a center winder device was used to obtain a thickness of 0.1 mm.
A film having a width of 140 cm was formed and wound on a winding core having an outer diameter of 90 mm at a winder speed of 120 m / min for 1500 m. For a period of 70 seconds from the start of winding, a pair of trim cutters was intermittently moved by 1 mm every 5 seconds to narrow the film width, and then the trim cutter was not moved and wound up with a constant width. The trim cutter was returned to the starting position just before the completion of winding. The film roll manufactured in this manner had no deformation such as bulging on its end surface. The film was not broken even when it was unwound.

Comparative Example A film roll was manufactured in the same manner as in Example except that the trim cutter was not moved. In this film roll, the most swollen convex deformation occurred at a position of ⅕ of the film laminated thickness from the core of the end face. This position was 140 m from the beginning of film winding. Also,
The end film bulged on the end surface of the roll film was bent toward the core.

Claims (5)

[Claims] 1. A continuous winding method for a resin film, which comprises continuously or intermittently narrowing a width of a supplied film at an initial stage of winding, in a method for continuously winding a resin film around a winding core. 2. The continuous winding method for a resin film according to claim 1, wherein the width of the supplied film is narrowed successively or intermittently until the winding is completed. 3. The continuous winding method for a resin film according to claim 1, wherein the film width which is narrowed during the winding is maintained. 4. The width of the supplied film is increased to the film width at the beginning of winding just before the winding is completed.
A continuous winding method for the resin film according to claim 3. 5. A resin film roll continuously wound around a winding core, wherein the resin film roll is wound such that the width of the resin film is gradually narrowed from the winding core toward the outer circumference.