JPH08175708A - Winding method for film - Google Patents

Abstract

PURPOSE: To provide a winding method of a film, which is capable of preventing the film where clarity is required, from laterally slipping in the course of winding the film, and winding the film without causing a graze and with a good appearance. CONSTITUTION: Recessed and projected parts 9 are formed at least on one side of both end parts of a film 5 sent out from the film manufacturing process, the heights of the projected parts are made higher than the average height of the film, and then the film is wound into the shape of a roll.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film winding method, and more particularly to a film winding method particularly suitable for a film which is required to have transparency.

[0002]

2. Description of the Related Art A film delivered from a film forming process is finally wound into a roll by a winder. By the way, in the case of a film which is required to have transparency, since it usually does not contain roughened fine particles for improving slipperiness,
If it is wound too tightly, scratches may occur due to rubbing between the films. Moreover, when the winding core (rolling core) has irregularities on its surface, protrusions appear on the surface of the wound product.

Further, since the film delivered from the film forming step has a large or small width pattern in the width direction, when such a film is wound in a roll shape, a thick portion of Due to the overlap, a hard winding portion called a so-called band is generated to cause permanent distortion in the film. And, the overlapping of thin parts causes wrinkles in the film. On the other hand, when it is loosely wound, lateral slippage is caused during winding.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is a film winding method particularly suitable for a film requiring transparency, which is being wound. It is an object of the present invention to provide a film winding method capable of preventing lateral slippage of the film, causing no scratches, and winding up with a good appearance.

[0005]

Means for Solving the Problems That is, the gist of the present invention is to form an uneven portion on at least one surface of both ends of a film delivered from a film forming step, and to set the height of the convex portion to a value higher than the average height of the film. A method of winding a film is characterized in that the film is raised and then wound into a roll by a winder.

The present invention will be described in detail below with reference to the accompanying drawings. A typical film to which the film winding method of the present invention is applied is a biaxially stretched polyester film. Biaxially stretched polyester film
First, a molten polyester resin is extruded from a die of an extruder and electrostatically adhered to a cooling rotary drum to form a sheet,
Then, it is obtained by biaxially stretching in the longitudinal and lateral directions in a film forming process consisting of a roll stretching machine and a stenter.
The film thickness after biaxial stretching is usually 12 to 50.
It is 0 μm, preferably in the range of 50 to 250 μm.

Then, the full width film delivered from the film forming process by the transport rolls is finally cut by the edge cutter into the two end ears that do not become a product and the central product film, and the product film. Is wound around the winding core of the winder, and the ears are discharged as slit ears.

A feature of the present invention is that, in winding the film as described above, a concavo-convex portion is formed on at least one surface of both ends of the film to make the height of the convex portion higher than the average height of the film, and then the film is wound. It is characterized by being wound into a roll by a taker. Further, in the present invention, the height of the convex portion is about 1 to 10% larger (thicker) than the average height of the film (the average height of the central film on which no unevenness is formed). Therefore, in the case of the winding method of the present invention,
The film is tightly wound at both ends and its center is loosely wound to contain an air layer.

In the present invention, it is preferable that the above-mentioned unevenness is formed by pressing a knurled (roughened) roll. The shape of the knurling is not particularly limited, and examples thereof include a twill shape.
In the case of a twill shape, the intersection of the oblique lines forms a convex portion on the film. That is, in the present invention, knurling for giving knurling
Thus, scratch patterns are formed on both ends of the film, and the thickness of both ends is slightly increased due to the scratch patterns.

The formation of irregularities (knurling) by pressing a knurled roll (knurling roll) is carried out at an arbitrary position after cooling the film, if a heating means such as a heat transfer heater is provided inside the knurling roll. However, it is preferable to carry out the treatment in the vicinity of the exit of the stenter because the residual heat of the film can be utilized. Then, in such a case, since both end ears (protuberances) of the film are to be cut after that, uneven portions are formed on at least one surface of both end ears inside the both end ears of the film delivered from the film forming process. Is formed to make the height of the convex portion higher than the average height of the film, and then both end ears are cut by the ears cutter and wound into a roll by a winder.

FIG. 1 shows a knurling process (unevenness forming process).
FIG. 1 is a schematic explanatory view showing an example of an apparatus, in which upper and lower knurling rolls (1) and (2) are arranged via a frame (3), and the knurling roll (1) is (2) arranged by an air cylinder (4). It is configured so that it can be pressed toward.
At least one of the peripheral surfaces of the knurling rolls (1) and (2) is knurled, and the end of the film (5) is inserted between the knurling rolls (1) and (2) to knurl. It is processed. In addition, the code | symbol (6) in a figure represents an ear.

FIG. 2 is an explanatory view when a knurling roll is arranged near the exit of the stenter. The knurling roll can be provided at an appropriate position near the exit of the oven (7) of the stenter. In the figure, reference numerals (1a) and (1a) and (1b) and (1b) respectively represent left and right knurling rolls arranged at both ends of the film (5). As described above, the knurling roll may be arranged inside or outside the stenter rail (8).

FIG. 3 is an explanatory view showing an example of the knurled film, but in the present invention, as shown in the drawing, a single knurling zone (9), () is provided at both ends of the film (5). 9) is formed.

In the present invention, as in the known method, the film is wound into a roll by a winder after cutting both end ears with an edge cutter. In this case, the winding hardness of the film can be arbitrarily controlled by synchronizing the oscillation in the film width direction between the ear cutter and the winder.

That is, FIG. 4 is an explanatory view showing an example of a cutting position of the knurled film, and FIG. 5 is an explanatory view showing an example of an end portion of the film after cutting.
As shown in FIG. 5, by arranging the cut line (10) in the knurling zone (9), as shown in FIG.
The amount of knurling zone (9) left on the edge of the film can be changed. As a result, the winding hardness of the film can be arbitrarily controlled by increasing or decreasing the amount of film strongly wound at both ends.

As a method of synchronizing the oscillation between the ear cutter and the winder, for example, EPC (Edge) is used.
Using the Position Control device,
By detecting the end of the product film, the method for synchronizing the oscillation between the ear cutter and the winder, specifically, the film detection sensor installed in the winder It is possible to employ a method in which the end portion is detected and the winder oscillation cylinder is driven by the EPC device, whereby the oscillation between the ear cutter and the winder is synchronized.

[0017]

According to the present invention described above, it is a film winding method particularly suitable for a film which is required to have transparency, which prevents lateral deviation during winding and prevents scratches from occurring. A method of winding a film is provided that can be wound up with a good appearance. Then, the winding hardness of the film can be arbitrarily controlled by synchronizing the oscillation of the selvage cutter and the winding machine during winding.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram showing an example of a knurling (unevenness forming) device.

FIG. 2 is an explanatory diagram of a case where a knurling roll is arranged near an exit of a stenter.

FIG. 3 is an explanatory diagram showing an example of a knurled film.

FIG. 4 is an explanatory view showing an example of a cutting position of a knurled film.

FIG. 5 is an explanatory view showing an example of the end portion of the film after cutting.

[Explanation of symbols]

 1: Knurling roll 2: Knurling roll 3: Frame 4: Air cylinder 5: Film 6: Ear 7: Oven 8: Stenter rail 9: Knurling zone 10: Cut line 1a: Knurling roll 1b: Knurling roll

Claims (4)

[Claims] 1. A film which is delivered from a film forming step is formed with a concavo-convex portion on at least one surface of both ends thereof to make the height of the convex portion higher than the average height of the film, and then wound into a roll by a winder. A method for winding a film, which is characterized in that the film is taken. 2. A film sent out from a film forming step is provided with a concavo-convex portion on at least one surface of both end portions inside both end portions of the film to make the height of the convex portion higher than the average height of the film, and then the both ends. The film winding method according to claim 1, wherein the ear portion is cut by an ear cutter and then wound into a roll by a winder. 3. After forming the concavo-convex portion, both end ears are cut by an ear cutter and wound in a roll shape by a winder by synchronizing oscillations of the ear cutter and the winder in a film width direction. The film winding method according to claim 2, wherein the film is wound. 4. The film winding method according to claim 1, wherein the uneven portion is formed by pressing a knurled roll.