JPH08133537A - Plastic film wider - Google Patents

Abstract

PURPOSE: To provide a plastic film winder by which a winding defect is not caused and a plastic film winding roll excellent in a winding posture can be obtained at high speed. CONSTITUTION: In a plastic film winder to wind a plastic film 8 while pressing it by a contact pressure roller 2, the plastic film winder has the contact pressure roller 2 composed of a roller on which an outside diameter of a roller lengthwise directional center part is smaller than an outside diameter of both end parts and a changing curve 3 of its outside diameter is approximated to a curve of a high order not less than a second order in the roller lengthwise direction.

Description

Detailed Description of the Invention

The present invention relates to a winding device for a plastic film. More specifically, it relates to a plastic film winding device capable of winding a thin and wide plastic film in a good winding shape and at high speed without causing defects such as wrinkles.

[Industrial applications]

Among the plastic films, polyethylene terephthalate, which is a highly functional plastic in terms of mechanical properties, thermal properties, electrical properties, etc.,
Films based on polyethylene 2,6 naphthalate, polypropylene, polystyrene, polyphenylene sulfide, aramid, etc. are widely used for applications such as magnetic tapes, capacitors, thermal transfer ribbons, and stencil printing. Further, in these applications, plastic films having a thickness of several μm to submicrons are produced and used with the progress of ultrathin film thickness technology.

[Prior art]

The above-mentioned plastic film is generally manufactured in a wide width and then wound into a roll, and subjected to coating, printing, vapor deposition, spattering and the like depending on the application. In these plastic films,
In addition to the characteristics of the final product, good processing suitability in the above-mentioned processing steps is also an important characteristic, and processing productivity is often greatly affected by the quality of the winding of the wide rolls. is there. Typical drawbacks that hinder productivity during this processing are problems such as vertical wrinkles, longitudinal wrinkles such as creases and electrostatic charging problems, or a winding roll that has no problems during winding, Vertical wrinkles, folds, horizontal wrinkles, etc. that occur over time after winding.

It is known that these winding form defects occur depending on the winding conditions, that is, the winding tension, the surface pressure, the winding speed, etc., but the thickness, width, and The easiness of occurrence also changes depending on the length, surface roughness, Young's modulus, slip property, and the like. In particular, these winding-shape defects related to wrinkles become more prominent as the thickness of the winding film becomes thinner, that is, as the "waist" and "buckling force" of the plastic film become weaker, the thickness of the plastic film It becomes harder to wind up without winding defects as it becomes thinner. In addition, the wider the winding roll, the more difficult it is to wind, making it more difficult to wind.

[0005]

In view of these problems, the present inventors have taken up a winding roll having an excellent winding appearance in which winding defects do not occur during or after winding a thin and wide plastic film. As a result of earnest research on a device for winding up a paper at high speed, the present invention has been accomplished.

That is, an object of the present invention is to provide a plastic film winding device which winds a plastic film into a roll while pressing the plastic film with a pressure roller.
Alternatively, it is to suppress the occurrence of wrinkles of the film due to changes over time and to obtain a winding roll having a good winding shape.

[0007]

A plastic film winding device of the present invention for this purpose is a plastic film winding device for winding a plastic film into a roll while pressing the plastic film with a pressure roller. The roller is composed of a roller whose outer diameter in the central portion in the roller longitudinal direction is smaller than the outer diameters of both ends, and the change curve of the outer diameter is approximated by a secondary or higher-order curve in the roller longitudinal direction. It consists of what is done.

That is, in the present invention, the change curve of the outer diameter of the contact pressure roller is approximated by a higher or higher order curve. The outer diameter change curve is preferably approximated to a higher-order curve as the thickness of the plastic film becomes thinner. It is secondary when the thickness is 12 μm or less and 3 when the thickness is 6 μm or less.
Next, it is preferable to be approximated by a quartic curve at 2 μm or less.

Further, the diameter of the portion of the pressure contact roller of the present invention through which the plastic film edge portion passes is 0.05% with respect to the minimum outer diameter in the central portion in the longitudinal direction of the pressure contact roller.
It is desirable to be 3% larger.

Further, the pressure contact roller is a roller covered with rubber, and the slip coefficient of the roller surface with the plastic film is preferably 0.03 to 0.8.

The wrap angle of the plastic film on the pressure roller is preferably 135 ° or more. Further, the winding apparatus for the plastic film of the present invention can be installed in a vacuum container.

Next, the present invention will be described in detail with reference to the drawings. 1 and 2 show a plastic film winding device according to an embodiment of the present invention. In the figure,
Reference numeral 1 indicates a winding roll. Plastic film 8
Is wound on the winding core 12 as a winding roll 1 while being pressed by the contact roller 2. The contact roller 2 is shown in FIG.
As shown in FIG. 3, the roller cylindrical core 6 and the rubber 4 coated on the roller cylindrical core 6 are provided, and the outer peripheral surface of the coated rubber 4 is the outer peripheral surface of the roller 2, that is, the change curve 3 of the outer diameter. Has been formed.

Regarding the outer diameter of the contact roller 2, the outer diameter of the central portion of the contact roller 2 in the longitudinal direction is smaller than that of both ends, and the change curve 3 of the outer diameter is the longitudinal direction of the contact roller 2. In, the roller is approximated by a second-order or higher-order curve.

By approximating the change curve 3 of the outer diameter of the contact roller 2 by a higher-order curve (surface), the wrinkles extended from the center can be more smoothly released to the outside (the end side of the plastic film). You can

In a winding device for a plastic film, it is general to wind by applying a winding tension and a surface pressure. For the winding tension, a hydraulic motor or an electric motor is used to supply torque with rotation. (Not shown). The surface pressure is applied by pressing the contact roller against the winding roll. The contact roller is usually rotatably supported at its shaft end and is connected to a pressurizing means such as a mechanism using a spring or a weight or a mechanism using air pressure, hydraulic pressure or electromagnetic force.

The pressing mechanism (contact pressure applying mechanism) to be applied in the present invention will be described in comparison with a conventional general pressing mechanism. 7 and 8 show a pressurizing mechanism that has been generally used in the past. In FIG. 7, the shaft portion 22 of the contact pressure roller 21 is rotatably supported by the bearing 23, and the contact pressure roller 21 is pressed against the take-up roll 25 by the pressurizing device 24 connected thereto, and the surface pressure is applied. ing. Since the contact pressure roller 21 bends due to the pressing force, the surface pressure at the central portion in the roller longitudinal direction becomes small or floats, making it difficult to apply a uniform surface pressure, making it difficult to obtain a good winding appearance. Become. In the pressure mechanism shown in FIG. 8, a bearing 32 is provided in the roll ring of the pressure roller 31, and a pressure device 34 is connected to a shaft 33 that does not rotate so that a surface pressure is applied to the winding roll 35. However, similarly to the example shown in FIG. 7, it is difficult to uniformly apply the surface pressure.

In the present invention, in order to apply a uniform surface pressure to the winding roll 1 by the pressure contact roller 2 over the entire width, for example, a surface pressure application mechanism as shown in FIGS. 3 to 6 is provided. That is, in the mechanism shown in FIG. 3, bearings 9 and 9'are rotatably supported by bearings 9 and 9'at two positions on both inner sides of contact roller 2, and shaft 7 supported by bearings 9 and 9'is bearing. It is rotatably supported by 10, 10 ',
The bearing 10 is connected to the bearing 10 by the pressurizing device 5 and
A bearing portion 11 made of a spring or the like is connected to the. Pressure device 5
And the bearing 11 applies a pushing / pulling force to the shaft 7,
As a result, the shaft 7 and the cylindrical core 6 are deflected, and the outer surface shape line at the portion on the winding roll 1 side of the outer diameter change curve 3 of the pressure roller 2 is substantially formed with respect to the surface of the winding roll 1. Correct so that they are parallel. As a result, the surface pressure applied from the contact roller 2 to the winding roll 1 becomes uniform in the roller longitudinal direction.

In the mechanism shown in FIGS. 4 and 5, the left and right one points are rotatably supported by bearings 9 in the roll ring, and 7a extending through the pressure roller 2 is formed by the bearing 9
And the force applied to the bearing 10 connected to the pressurizing device 5 is used for bending. In this mechanism, no force is applied to the cylindrical core 6 itself from the side of the shaft 7a, but since the cylindrical core 6 is supported by the bearing 9 at the central portion in the longitudinal direction, the structure shown in FIGS. No deflection in the undesired direction occurs over the entire length of the roller as shown, and the outer surface of the pressure roller 2 naturally follows the outer surface of the take-up roll 1. As a result, as shown in the figure, the outer surface shape line at the portion on the winding roll 1 side of the outer diameter change curve 3 of the pressure roller 2 is substantially parallel to the surface of the winding roll 1. The deflection of the entire contact roller 2 is corrected. As a result, the surface pressure applied from the contact roller 2 to the winding roll 1 becomes uniform in the roller longitudinal direction.

FIG. 6 shows a mechanism in which the weight of the contact roller 2 itself is simply used for applying the surface pressure. When the weight of the contact pressure roller 2 has a great influence on the surface pressure application direction, the deflection of the contact pressure roller 2 due to the weight can be corrected by the deflection by the pressure device 5. In such a case, it is sufficient to simply provide the pressurizing device 5 as in the conventional mechanism, but since the control range of the magnitude of the surface pressure capable of providing a uniform surface pressure is limited, this mechanism is used. Is applicable only when there is no need to change so much.

In the surface pressure imparting mechanism as described above, the balance between the amount of deflection of the cylindrical core 6 as the core of the contact roller 2 and the applied pressure is important, so the structure and material of the cylindrical core 6 becomes a problem. . Since the applied pressure changes depending on the surface pressure required for winding, the amount of bending of the cylindrical core 6 also changes. In order to uniformly apply the surface pressure, it is necessary to calculate the amount of deflection that matches the applied pressure and select the material of the cylindrical core 6, especially the thickness, Young's modulus, and outer diameter. Further, in the present invention, since the outer diameter of the pressure roller 2 is changed in the longitudinal direction, in order to uniformly apply the surface pressure to the winding roll 1,
The amount of deflection of the roller is determined by calculation or by trial and error taking into consideration the amount of change in outer diameter and the applied pressure. Cylindrical core 6
Examples of the material include, but are not limited to, iron, aluminum, glass fiber reinforced plastic, carbon fiber reinforced plastic, and the like.

Further, it is preferable that the portion of the contact roller 2 in contact with the take-up roll 1 is covered with rubber 4 so that a more uniform surface pressure can be applied to the take-up roll 1. Regarding the rubber hardness for keeping the contact area of the pressure roller 2 with the winding roll 1 due to the deformation of the rubber 4 and the range of the wall thickness, the rubber hardness is preferably 35 ° to 90 ° shore. Not limited. The thickness of rubber is 1 mm to 4
0 mm is suitable, but not limited to this. Examples of the rubber material include, but are not limited to, rubber materials including chlorosulfonated polyethylene, acrylonitrile butadiene, chloroprene, ethylene propylene, butyl, silicone rubber and the like.

Further, in the present invention, the contact roller 2
The outer diameter of the portion through which the edge portion of the plastic film 8 passes is 0.05 to 3% larger than the minimum outer diameter at the central portion in the longitudinal direction of the contact roller 2. 0.0
If it is less than 5%, the wrinkle-stretching effect is less likely to be exhibited, and if it is more than 3%, the plastic film 8 is used.
It is not preferable because it is easily scratched and the width of the plastic film 8 on the roller 2 varies.
By setting it in the range of 0.05 to 3%, it becomes possible to smoothly release the wrinkles from the central portion of the roller to both outer sides in the longitudinal direction.

Considering the role of the pressure roller 2, the main role is first to suppress the entrainment of air in the take-up roll 1, that is, between the film winding layers, and to squeeze out the entrained air to form an air layer. The purpose of this is to prevent winding defects during and after winding. Here, the present inventors have reached the present invention by paying attention to another effect of the pressure contact roller 2 that the film 8 fed to the winding roll 1 is widened on the pressure contact roller 2. That is, the fed film 8 is
By wrapping around the pressure contact roller 2, a widening force is generated in the plastic film 8 itself, so that a wrinkle naturally expands on the pressure contact roller 2 and is wound around the winding roll 1 without wrinkles. In this case, if the thickness of the film 8 is large, the rigidity of the film 8 is high, the diameter of the pressure contact roller 2 is small, and the wrapping angle around the pressure contact roller 2 is large, this effect is large. It becomes an important element because it is tightened.

Further, in order to improve this wrinkle-extending effect, in the case of the conventional contact roller having no change in outer diameter, it is important that the film and the contact roller have a good slip on the roller. It was In order to assist this widening action immediately before winding, for example, an expander roll 13 as shown in FIG. 9 was installed immediately before winding (in front of the pressure roller). In this method, as shown in FIG. 9, one roller 13 is bent from a center as a starting point with a certain curvature to orient the rotation directions of both end sides in an oblique direction and widen the plastic film in the width direction. is there.

However, in such a method, although a widening force in the width direction is generated on both end sides of the film, an extra pulling force is applied to the central portion of the film in the longitudinal direction,
The extra pulling force may cause wrinkles over time after winding, which is not preferable. In addition, even if the width is once widened, it may return to the original state before being fed to the winding roll, and thus the wrinkle removing function is not often exhibited sufficiently.

Therefore, in the present invention, as a result of earnest research on a device for winding the take-up roll 1 at the central portion thereof, without generating extra tension in the longitudinal direction and before the widening force has recovered. By using the contact pressure roller 2 exhibiting a widening action at both ends of the plastic film 8 so as to form a winding device capable of widening the plastic film 8 at the same time as winding, a good winding shape can be obtained at high speed. It became so. That is, in the wide contact roller 2 having a surface pressure applying mechanism that evenly applies surface pressure to the winding roll 1, the outer diameter of the central portion is smaller than the outer diameters of both ends thereof, and the plastic film By making the outer diameter of the edge passage portion of No. 8 larger than the central portion, the effect intended by the present invention can be obtained.

Further, in the present invention, it is preferable that the coating rubber 4 on the surface of the pressure contact roller 2 is slippery treated. As a method of slippery treatment, a method using a weak acid solution, forming minute cracks on the surface by ultraviolet rays, forming minute protrusions on the rubber surface by adding an inorganic filler during rubber molding, or simply surface polishing There are some ways to improve slippage. However, the method is not limited to the above method, and it is possible to appropriately select from other known methods.

In the conventional pressure contact roller, as described above, in order to wrap the plastic film around the pressure contact roller 2 to maximize the wrinkle-extending effect, the contact pressure roller 2 having a good sliding property should be used. I have to. On the other hand, in order to enhance the wrinkle-extending effect by changing the outer diameter as in the present invention, it is preferable to use the contact roller 2 which has a low slip, that is, has a high friction to some extent. That is, the wrinkle-stretching effect due to the winding on the pressure-contact roller and the wrinkle-stretching effect due to the change in the outer diameter of the pressure-contact roller require mutually opposite properties in terms of the slipperiness with the film.

Therefore, in the present invention, the contact roller 2
It is desirable to control the slip coefficient between the surface of the contact roller 2 and the plastic film 8 in an optimum range in order to provide a good wrinkle-stretching effect and satisfy the above-mentioned contradictory requirements. That is, the slip coefficient during this period is preferably 0.03 to 0.8. 0.03
If it is less than the above range, the sliding property is too good and the effect of changing the outer diameter is weakened, which is not preferable. On the other hand, if it exceeds 0.8, the friction becomes high, and the wrinkles of the plastic film 8 remain particularly in the central portion of the pressure roller 2, and the film 8 is scratched, which is not preferable.

Further, in the present invention, the roller diameter and the winding angle θ when the plastic film 8 is wound around the wide contact roller 2 are important. The winding angle θ is 13
It is set to 5 ° or more, but more preferably 150 °
It is above, and more preferably 180 ° or more. 1
If it is less than 35 °, the effect of straightening wrinkles is small, which is not preferable.

The diameter of the pressure roller 2 is preferably made smaller, but the length of the roller is restricted by the width of the plastic film 8 to be wound up, so that the condition for making the diameter smaller may not always be satisfied. However, it is preferable that the diameter of the roller is as small as the manufacture of the roller allows. For example, if the thickness of the plastic film 8 is 4 μm or less, it is preferably 80 mm or less.

The plastic film winding device of the present invention may be installed under atmospheric pressure or in a vacuum container. When it is installed in a vacuum container, it is not necessary or necessary to remove entrained air, so that there is an advantage that tension and surface pressure can be set low.

The present invention will be described below with reference to more concrete examples. Evaluation of each characteristic in the present invention was carried out by the following measuring methods. (1) Slip coefficient (μ) The film thickness of 100 mm width with the roller fixed is 12μ
m polyester film (“Lumirror” manufactured by Toray Industries, Inc.)
Wrap type P11) and vertically weight W = 500
Suspend g, and place the opposite film edge in the 90 ° direction (horizontal)
The slip coefficient μ was obtained from the tension T when the film first started to move when it was pulled to. μ = 2 / πln (T / W)

(2) Defects in winding form Defects in winding form were evaluated based on the appearance of the winding roll during and after winding, according to the criteria shown in Table 1 below.

[0035]

[Table 1]

[0036]

【Example】

Examples 1 to 6 and Comparative Examples 1 to 8 Using carbon fibers, chloroprene rubber was wrapped around the cylindrical core of carbon fiber reinforced plastic (CFRP) molded with epoxy resin and surface-treated according to the present invention. The rubber hardness was 65 ° Shore. Further, the surface pressure applying mechanism shown in FIG. 3 was applied as an apparatus for applying a uniform surface pressure.
Table 2 shows the specifications of the contact roller. On the other hand, in the comparative example, the cylindrical core and the mechanism for uniformly applying the surface pressure were the same as those in the example, and the comparison was performed by changing the outer diameter, the surface specification of the roller, and the winding angle of the film.

As the plastic film, a polyethylene terephthalate film which has been biaxially stretched and then heat-treated is used, and the thickness is 12 μm (Example 1), 6 μm (Example 2) and 2 μm (Example 3), respectively 1000 mm,
180 mm and 500 mm width films, respectively
It was wound up with a product roll of 00 m, 20000 m, and 30,000 m, and the evaluation results are shown in Table 3 together with Comparative Examples 1 to 5.

A film having a thickness of 2 μm and a width of 3.5 m is used.
The result was shown in Table 3 together with Comparative Examples 6 and 7 by winding up with a length of 60000 m (Example 4). Furthermore, thickness 2μ
Width of 315 mm and length of 30000 m 10
It was rolled up in a Torr vacuum container (Examples 5 and 6) and shown in Table 3 together with Comparative Example 8.

[0039]

[Table 2]

[0040]

[Table 3]

[0041]

According to the winding apparatus for a plastic film of the present invention, a plastic film having a good winding shape in which a thin plastic film is not rolled up such as wrinkles and wrinkles do not occur over time after winding. The winding roll can be wound at high speed.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a plastic film winding device according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a contact roller of the apparatus of FIG.

FIG. 3 is a partial cross-sectional view showing an example of a surface pressure applying mechanism according to the present invention.

FIG. 4 is a partial cross-sectional view showing another example of the surface pressure imparting mechanism of the present invention.

FIG. 5 is a partial cross-sectional view showing still another example of the surface pressure imparting mechanism of the present invention.

FIG. 6 is a partial cross-sectional view showing still another example of the surface pressure imparting mechanism of the present invention.

FIG. 7 is a partial cross-sectional view of a conventional plastic film winding device.

FIG. 8 is a partial cross-sectional view of another conventional winding device for a plastic film.

FIG. 9 is a perspective view of a general expander roll.

[Explanation of symbols]

 1 Winding Roll 2 Contact Pressure Roller 3 Outer Diameter Change Curve 4 Coated Rubber 5 Pressurizing Device 6 Roller Cylinder Core 7, 7a Shaft 8 Plastic Film 9, 9 ', 10, 10' Bearing 11 Means for Deflection 12 Rolls Core θ Winding angle

Claims (5)

[Claims] 1. A plastic film winding device that winds a plastic film into a roll while pressing the plastic film with a pressure roller, wherein the pressure roller is such that the outer diameter at the central portion in the roller longitudinal direction is larger than the outer diameter at both ends. A winding device for a plastic film, characterized in that it is composed of a roller whose outer diameter is small and whose change curve of the outer diameter is approximated to a secondary or higher-order curve in the longitudinal direction of the roller. 2. The plastic film according to claim 1, wherein an outer diameter of a portion of the contact pressure roller through which an edge portion of the plastic film passes is larger by 0.05 to 3% than a minimum outer diameter at a central portion in the longitudinal direction of the roller. Winding device. 3. The pressure contact roller is a roller whose surface is coated with rubber, and the sliding coefficient between the roller surface and the plastic film is 0.03 to 0.8. Winding device for plastic film. 4. The wrapping angle of the plastic film around the pressure roller is 135 ° or more.
The winding device for the plastic film according to any one of 1. 5. The apparatus according to claim 1, which is installed in a vacuum container.
5. The winding device for a plastic film according to any one of 1 to 4.