JPH11286360A - Winding device of thermoplastic resin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve the stable charging state of a thin and smooth film and to improve the air excluding property and the adhesion force between the films by mounting a charged roller through which a film is passed, on the upstream of a winding part. SOLUTION: A running film 1 cut by a specific width of a product just before a conveying roller 2 is charged by a charging electrode 5a when it is passed through a conveying roller 3. Further the other face of the film 1 is charged when the film 1 is passed through a pressure contact roller 4 charged by a charging electrode 5b. Then the film 1 layers are closely kept into contact with each other when the film 1 is rolled or after the film 1 has been rolled for excluding the air between the film layers to complete a product roll 8. The positive and negative potentials can be optionally applied, but the negative charge is preferred to a polyester film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film winding apparatus for preventing a roll of a thermoplastic resin film from slipping.

[0002]

2. Description of the Related Art When winding a thermoplastic resin film, there is a problem of misalignment. Winding is a phenomenon in which air remaining between layers of a film acts as a lubricant and the film is displaced by some impact. Conventional methods for preventing winding deviation include a method in which a contact pressure roll is provided to eliminate air remaining between layers of the film, and a method in which static electricity is applied to the film itself to improve the adhesion between the film and the film. Are known.

[0003] The method using a contact pressure roll regulates the diameter, material, surface hardness, surface slipperiness and the like of the contact pressure roll to improve the ability to remove air (for example, Japanese Patent Application Laid-Open No. Sho 50-1985).
156566). As a method of applying static electricity to the film itself and improving the adhesion, there is known a method in which a film is sandwiched between rolls and gripped by being charged in advance before the film is brought into contact with the roll and wound up. (For example, JP-A-51-46354 and JP-A-2-169457).

[0004]

In the former method among the above-mentioned conventional methods, when winding a film having a smooth surface and poor slipperiness, it is necessary to suppress the occurrence of wrinkles and to reduce the deformation of the film. If the tension is low, the rolled end face may be stray winding or the slippage may be out of alignment. Conversely, if the contact pressure of the contact pressure roll is increased to suppress stray winding and slippage, the friction between the contact pressure roll and the film increases, causing local deformation of the film,
The unevenness of static electricity generated at the time of peeling of the film from the contact pressure roll becomes large, and it is not possible to obtain a product having a good rolled shape.
Therefore, the selection range of the surface hardness and the surface slipperiness of the contact pressure roll for satisfying the generation of wrinkles, uneven static electricity and stray winding is extremely narrow.

In the latter method, since the film is directly charged, a discharge phenomenon occurs in a thin film having a thickness of 10 μm or less, which may cause a hole in the film or uneven charging.

An object of the present invention is to solve the above problem by forming a stable charge state even on a thin and smooth film, and improving the air rejection and the adhesion between the film and the film. It is another object of the present invention to prevent stray winding and winding deviation when winding a film into a roll.

[0007]

In order to solve the above-mentioned problems, a thermoplastic resin film winding device according to the present invention is a device for winding a thermoplastic resin film into a roll.
A roll provided with a charge through which the film passes is provided upstream of the winding section.

This device monitors the charge amount of the roll to which the above-mentioned charge has been added, and further applies a charge to the roll so that the charge amount of the roll becomes constant. Then, the film is passed through a film and wound into a roll. Preferably, it is a device.

In such a winding device, a predetermined static charge is applied to the film from a charged roll immediately before being wound into a roll, and after the film is formed into a film having a uniform charge amount. It will be wound up. At the time of winding, the electrostatic attraction due to the electric charge improves the adhesion between the films and the efficiency of removing air, thereby preventing the film from being unwound. This device is very effective especially when winding a thin and smooth film for a magnetic material.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. The thermoplastic resin film in the present invention is not particularly limited, but typical examples include polyethylene terephthalate, polyethylene-2,6-naphthalate, polypropylene, nylon-6, polyphenylene sulfide film and the like. The film thickness can be applied to a film having a thickness of about 3 to 25 μm, but is particularly effective for a thin film having a thickness of 10 μm or less. The film can be effectively applied with a surface roughness of 3 to 50 nm in average surface roughness, but is particularly effective for a film having an average surface roughness of 10 nm or less. As a material of the roll for imparting electric charge, synthetic rubber such as EPT rubber, EPDM rubber, polychloroprene rubber (neoprene), and hypalone rubber is suitable.

A needle-shaped electrode is suitable as an electrode for applying a charge. The potential may be positive or negative, but a negative charge is more effective for polyester films. The roll for applying the electric charge may be a transport roll or a contact pressure roll immediately before winding as long as the roll is located upstream of the winding section in the film traveling direction. Alternatively, both rolls may be charged.

Further, in the present invention, it is possible to control the charge amount of the contact pressure roll after charging the transport roll. As a means for controlling the charge amount, it is effective to adjust the voltage of the device itself for applying the electric charge and the like, and also to provide a neutralizer. The static eliminator is not limited to a self-discharge type, a nozzle type or the like.

A typical embodiment of a thermoplastic resin film winding device according to the present invention will be described with reference to the drawings. FIG. 1 shows a charging section and a winding section of a winding apparatus for a thermoplastic resin film according to an embodiment of the present invention. In the figure, 1 is a running film, 2 and 3 are transport rolls, 4
Is a contact pressure roll, 5a and 5b are charging electrodes, 6 is a self-discharge type static eliminator, 7 is a nozzle type static eliminator, and 8 is a wound product roll. The traveling film 1 cut to a predetermined product width immediately before the transport roll 2 receives the electric charge when passing through the transport roll 3 charged with the charging electrode 5a and removes the air between the film layers by the contact pressure roll 4. It is removed and wound up as a product roll 8. Also, when the film 1 passes through the contact pressure roll 4 to which the charge is applied from the charging electrode 5b, the charge is applied to the opposite surface of the film 1 and the film 1 is wound up in a roll shape or after being wound up. Then, the film layers are brought into close contact with each other to eliminate air in the film layer phase, and the film is wound up as a product roll 8. As a result, the air gap between the film layers and the winding deviation due to the escape of the air are effectively prevented.

When a monitor for the charge amount of the roll is provided, an electrostatic charge measuring device may be provided so as to face the transport roll 3 and / or the contact pressure roll 4. Based on the amount of charge measured by this electrostatic charge measuring device, each charged electrode 5
a, 5b and / or the set amount of the static eliminators 6, 7 may be controlled.

[0015]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples. The physical properties and measured values shown in the examples are based on the following methods.

(1) Film average surface roughness Three-dimensional fine shape measuring instrument (Model ET-30H) of Kosaka Laboratory
K) and a three-dimensional surface roughness analysis system (method MAR)
Using MEC-3C), three-dimensional surface roughness (center plane average roughness) was measured. The conditions were as follows, and the value was an average value of 20 measurements.・ Tip tip radius: 0.5 μm ・ Load of the stylus: 4 mg ・ Vertical magnification: 50,000 times ・ Horizontal magnification: 200 times ・ Cutoff: 0.25 mm ・ Feed pitch: 5 μm ・ Measuring length: 500 μm ・ Measurement Area: 0.197 mm ² · Measurement speed: 100 µm / sec

(2) Product Roll Hardness A 1 kg weight was attached to a Shimadzu Rubber Hardness Tester 200 manufactured by Shimadzu Research Institute Co., Ltd., and 10 points in the width direction of the product roll were measured, and the average value was taken as the hardness.

Example 1 Using a device shown in FIG. 1, a film having a thickness of 6 μm, an average surface roughness of 7 nm on the front surface and 14 nm on the back surface was wound with a winding tension of 8 kg.
/ M, the contact pressure of the contact pressure roll is 45 kg / m, and the charging voltage is-
The film was wound at 10 kV at a conveying speed of 180 m / min to obtain a film roll having a surface shore hardness of 95 °. The film roll had no winding deviation, wrinkles, uneven charging and the like, and had a good rolled shape including the inner layer of the roll.

Example 2 Using a device shown in FIG. 1, a film having a thickness of 14 μm and an average surface roughness of 9 nm was wound at a tension of 10 kg / m, a contact pressure of a contact pressure roll was 30 kg / m, and a charging voltage was − The film was wound at 10 kV at a conveying speed of 450 m / min to obtain a film roll having a surface layer Shore hardness of 92 °. The film roll had no winding deviation, wrinkles, and uneven charging, and had a good rolled shape including the inner layer of the roll.

Comparative Example 1 Using a device shown in FIG. 2, a film having a thickness of 6 μm, an average surface roughness of 7 nm on the front surface and 14 nm on the back surface was wound with a winding tension of 8 kg.
/ M, the contact pressure of the contact pressure roll is 45 kg / m, and the charging voltage is-
10 kV was applied directly from the charging electrode 10 to the film and wound up. Since the film was directly charged, the charge amount became large, and even after the film roll was neutralized by the static eliminator 11, the charge of the film roll could not be completely reduced, and a product usable as a product could not be obtained. Note that reference numerals 12 and 13 in FIG. 2 denote control devices for adjusting the charge amount and the charge removal amount.

COMPARATIVE EXAMPLE 2 A film having a thickness of 14 μm and an average surface roughness of 9 nm was wound on a film having a thickness of 14 kg / m, a contact pressure of a contact pressure roll was 30 kg / m, and a conveying speed was 450 m / using the apparatus shown in FIG. The film was wound up in minutes without giving a charge to obtain a film roll having a surface shore hardness of 91 °. The end of the film roll had a winding deviation, and in some places the film had popped out.

[0022]

According to the film take-up device of the present invention, it is possible to improve the air exclusion property and to take up the product without causing uneven charging, as compared with the conventional method for preventing the winding deviation. As a result, a high-quality product can be obtained, which can greatly contribute to improvement in productivity.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram including a charge applying unit of a winding device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a winding device used in Comparative Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Running film 2, 3 Transport roll 4 Contact pressure roll 5a, 5b Charging electrode 6 Self-discharge type static eliminator 7 Nozzle type static eliminator 8 Product roll

Claims (3)

[Claims] 1. An apparatus for winding a thermoplastic resin film into a roll, comprising a roll provided with an electric charge through which the film passes, upstream of a winding section. 2. The thermoplastic resin film winding device according to claim 1, wherein means for monitoring the charge amount is connected to the charged roll. 3. The winding device for a thermoplastic resin film according to claim 1, further comprising an applied charge control unit that controls the charge amount of the roll provided with the charge to be constant.