JP2016185840A - Film wrinkle smoothing device and method for manufacturing film using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film wrinkle smoothing device capable of suppressing damage of a film and occurence of electrostatic charge.SOLUTION: A film wrinkle smoothing device 1 which sucks the air from above or below a film being transported is provided with a nearly columnar rotor 2. An almost circular surface of the rotor is almost vertical to a film width direction, and the rotor rotates around a rotor support body 3. On surfaces other than the almost circular surface of the rotor, a plurality of air suction holes 2a are formed into a radial shape around the axis. The nearer to the end part side in the film width direction the air suction holes are positioned, the smaller the volume becomes.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a film wrinkle-stretching apparatus capable of suppressing the generation of scratches and charges on a film.

  In order to prevent the generation of wrinkles in the film production process, a wrinkle stretching apparatus for films is used. As conventional film wrinkle stretching apparatuses, those shown in Patent Document 1 and Patent Document 2 are known. The film wrinkle-stretching device of Patent Document 1 stretches wrinkles by applying a tensile force to the film by bringing a plurality of rollers into contact with the film while sucking the film from the air suction port with negative pressure. Moreover, the wrinkle-stretching apparatus of the film of patent document 2 is a thing which pinches | interposes a film with the cross guider which consists of three rollers arrange | positioned at the both ends of a film, applies a tensile force to a film, and stretches wrinkles.

JP 2008-81274 A JP 2009-234713 A

  However, in the methods described in Patent Document 1 and Patent Document 2, when the wrinkle of the film is stretched, the film excessively contacts a structure such as a frame or a roller. The problem is that it cannot be used when processing such as applying a coating liquid on the back surface. An object of the present invention is to provide a wrinkle-stretching device for a film that improves the drawbacks of the prior art and can suppress the generation of scratches and charges on the film.

In order to solve the above problems, the present invention has the following configuration.
(1) A wrinkle stretching device for a film that sucks air from the upper side or the lower side of the film being transported, comprising a substantially cylindrical rotor, wherein the substantially circular surface of the rotor is substantially perpendicular to the film width direction, The rotor rotates about a rotor support, and a plurality of air suction holes are formed radially on the surface other than the substantially circular surface of the rotor, and the air suction holes are formed in the film width direction. The apparatus for wrinkling and stretching a film is characterized in that the volume of the film becomes smaller as it is positioned closer to the end of the film.
(2) The rotor has an R surface at an end portion thereof, and an R value that is a curvature of the R surface is 1/20 or more of a diameter of a substantially circular surface of the rotor. Wrinkle-stretching device for the film described.
(3) A method for producing a film, characterized in that the film wrinkling device according to claim 1 or 2 is used.

  According to the present invention, it is possible to provide a film wrinkle-stretching device that can suppress the generation of scratches and electrification of the film. The wrinkle-stretching apparatus for a film of the present invention can perform a wrinkle-stretching process even when there is a step of applying a coating liquid to the back surface of the film.

The top view which shows an example which has arrange | positioned the wrinkle-stretching apparatus of the film of this invention in the film width direction both ends FIG. 1 is a cross-sectional view taken along line II in FIG. 1 for explaining an example of a film wrinkle stretching apparatus of the present invention. II-II cross-sectional arrow view in FIG. 1 for explaining an example of the film wrinkle stretching apparatus of the present invention View from top of example of rotor support View from the side of one example of rotor support View from bottom of example rotor support

  The film wrinkle stretching apparatus of the present invention is a film wrinkle stretching apparatus for sucking air from the upper side or the lower side of a film being transported, and includes a substantially cylindrical rotor, and the substantially circular surface of the rotor has a film width. The rotor rotates about a rotor support as an axis, and a plurality of air suction holes are radially formed around the axis on a surface other than the substantially circular surface of the rotor, and the air It is important that the volume of the suction hole becomes smaller as the suction hole is located on the end side in the film width direction.

  Although the desirable form for implementing this invention is demonstrated below, this invention is not limited to this.

  In the wrinkle stretching apparatus for a film of the present invention, it is important to suck air from the upper side or the lower side of the film being transported from the viewpoint of suppressing the deflection of the film during the transport process. In consideration of appropriately correcting the deflection due to the gravity of the film, it is preferable to suck air from the lower side of the film being conveyed.

  The film wrinkle stretching apparatus of the present invention includes a substantially cylindrical rotor from the viewpoint of reducing a load caused by contact between the apparatus and the film, and the substantially circular surface of the rotor is substantially perpendicular to the film width direction. It is important to rotate about the rotor support.

  Here, the substantially circular column refers to a circular column, an elliptical column, a truncated cone, and an elliptical truncated cone, and the substantially circular surface refers to a circular surface or an elliptical surface. The cylinder, the elliptical column, the truncated cone, and the elliptical truncated cone include those obtained by rounding a portion where a substantially circular surface and a surface of another shape are in contact with each other. The film width direction refers to a direction that is parallel to the film transport surface and orthogonal to the direction in which the film proceeds during film production (film longitudinal direction). That the substantially circular surface of the rotor is substantially perpendicular to the film width direction means that the angle formed by the substantially circular surface of the rotor and the film width direction is not less than 85 ° and not more than 95 °. In addition, rotating about the rotor support as an axis means that the rotor rotates about the shaft portion of the fixed rotor support.

  Since the substantially circular rotor is provided and the substantially circular surface of the rotor is substantially perpendicular to the film width direction, the area where the wrinkle-stretching device is in contact with the film is reduced. Moreover, the substantially circular surface of the rotor is substantially perpendicular to the film width direction, and the rotor rotates about the rotor support provided on the substantially circular surface, so that friction between the apparatus and the film can be suppressed.

  The shape of the rotor is not particularly limited as long as the effects of the present invention are not impaired. From the viewpoint of suppressing the film being conveyed from moving up and down due to the rotation of the rotor, it is preferably a true cylinder.

  In the film wrinkle stretching apparatus of the present invention, from the viewpoint of keeping the air suction amount constant even when the rotor rotates, a plurality of air suction holes are radially formed around the axis on a surface other than the substantially circular surface of the rotor. It is preferable to be formed. Here, a plurality of air suction holes formed radially on the surface other than the substantially circular surface means that when the vertical line is drawn outward from the shaft, the vertical line indicates the rotor or air. It means that a plurality of air suction holes are formed on a surface other than a substantially circular surface so that the air suction holes can pass through without touching the wall surface of the suction holes.

  In the film wrinkle stretching apparatus of the present invention, it is important that the volume of the air suction hole is smaller as the position of the air suction hole is closer to the end in the film width direction from the viewpoint of suppressing charging on the end in the film width direction. is there. The closer to the end in the film width direction, the smaller the volume of the air suction hole, so that the suction pressure at the end in the film width direction becomes lower than that at the center in the film width direction. It is possible to suppress charging on the direction end side.

  The method of reducing the volume of the air suction hole located on the end side in the film width direction is not particularly limited as long as the effect of the present invention is not impaired. Specific examples thereof include a method of using a rotor whose outer shape is a columnar shape and whose wall thickness increases toward the center in the film width direction, and the outer shape is in the film width direction rather than the diameter of the circular surface on the film width direction end side. There is a method of using a rotor in which the circular surface on the center side has a large truncated cone shape and the inner diameter is constant.

  For example, when using a rotor whose outer shape is a cylindrical shape and the wall thickness increases toward the center in the film width direction, by making the hole diameter of the air suction hole constant and increasing the difference in the wall thickness of the rotor, The difference in volume between the air suction holes on the end side and the center side in the film width direction can be increased.

  In addition, when using a rotor whose outer shape is a truncated cone having a larger diameter of the circular surface on the center side in the film width direction than the diameter of the circular surface on the end side in the film width direction, and the inner diameter is constant, By making the hole diameter of the air suction hole constant and increasing the difference in the diameter of the circular surface of the rotor, the difference in the volume of the air suction hole on the end side and the center side in the film width direction can be increased. However, if the difference in the diameters of the circular surfaces of the rotor increases, the inclination of the film surface increases in the vicinity of the rotor, causing scratches and charging on the film. Therefore, the diameter ratio of the circular surface of the rotor (the diameter of the circular surface on the film width direction end side / the diameter of the circular surface on the center side of the film width direction) is preferably 0.8 or more and less than 1.0.

  In the film wrinkle-stretching apparatus of the present invention, from the viewpoint of preventing the occurrence of scratches on the film, there is an R surface at the end of the rotor, and the R value, which is the curvature of the R surface, is the value of the substantially circular surface of the rotor. It is preferably 1/20 or more of the diameter. Here, the R surface at the end of the rotor means a state where the boundary between the circular surface of the rotor and the other surface is a curved surface. The R value, which is the curvature of the R surface, is the longest length of the radius of the curved portion in the cross section obtained by cutting the rotor in a plane parallel to the axis and parallel to the axis. Say. The R value is an index of the degree of bending, and increases as the degree of bending increases. When the R value is 1/20 or more of the diameter of the substantially circular surface of the rotor, it is possible to suppress the occurrence of film scratches due to contact with the rotor during film conveyance.

  The location of the film wrinkle stretching apparatus of the present invention is not particularly limited as long as the effect of the present invention is not impaired, but wrinkles of the film are likely to occur in a process in which the film is not in contact with a roll or a clip. Or between the tenter and the winding process.

  The film production method of the present invention is a film production method characterized by using the film wrinkle stretching apparatus of the present invention. By the film manufacturing method of the present invention, the film can be prevented from being scratched or charged in the manufacturing process, and a high-quality film without wrinkles can be obtained.

  Next, specific examples of the film wrinkle stretching apparatus of the present invention will be described with reference to the drawings. However, the present invention is not limited to these.

  FIG. 1 is a plan view showing an example in which the film wrinkle stretching apparatus of the present invention is disposed at both ends in the film width direction. The wrinkle-stretching device 1 includes a cylindrical rotor 2 in which a large number of air suction holes 2a are formed. By drawing air from the air suction holes 2a, the wrinkle formed at the end in the film width direction is stretched. . The wrinkle-stretching device 1 may be arranged on either the upper side or the lower side of the film 6 being transported. However, considering that the deflection of the film 6 due to gravity is appropriately corrected, the lower side of the film 6 being transported It is preferable to arrange in the.

  Next, a cross-sectional view taken along the line II in FIG. 1 for explaining an example of the film wrinkle stretching apparatus of the present invention (FIG. 2), and in FIG. 1 for explaining an example of the film wrinkle stretching apparatus of the present invention. A specific example of the structure of the film wrinkle stretching apparatus 1 according to the present invention will be described with reference to FIG.

  The wrinkle stretching device 1 includes a rotor 2, a rotor support 3, a frame 4, and a negative pressure chamber 5. The rotor 2 has a cylindrical shape, has a hollow inside, and increases in thickness toward the center in the film width direction, and has a large number of air suction holes 2a formed on a surface other than the circular surface. The rotor 2 is installed so as to cover other than the shaft portion 3a of the rotor support 3 to be described later, and has a structure that can freely rotate as the film 6 is conveyed. The hole diameter (diameter) of the air suction hole 2a is preferably 1 mm or more and 5 mm or less.

  The rotor support 3 is formed of a portion (hereinafter referred to as a body portion) having a shape that fits into a cavity inside the rotor 2, and a shaft portion 3a that is provided at both ends of the rotor support 3 and serves as an axis when the rotor rotates. A through-hole (negative pressure introduction passage 3d) through which air passes is formed in the body portion of the rotor support 3, and the film 6 conveyance side portion (negative pressure operation port 3b) of the through-hole is parallel to the axis. The negative pressure chamber 5 side (negative pressure introduction port 3c) of the through hole can be appropriately changed according to the shape of the inlet of the negative pressure chamber 5, but here the negative pressure action The length in the direction parallel to the axis is shorter than that of the mouth 3b, and the length in the direction perpendicular to the direction is substantially rectangular (FIGS. 4 to 6). In addition, since the rotor support body 3 is being fixed by the flame | frame 4, itself does not rotate.

  The frame 4 fixes the rotor support 3, and a negative pressure chamber 5 connected to a negative pressure source (not shown) is integrally formed at a lower portion of the frame 4.

  As shown in FIG. 3, the negative pressure chamber 5 connected to a negative pressure source (not shown) communicates with the negative pressure introduction port 3c via the air suction hole 2a of the rotor 2, and the negative pressure introduction port 3c is negative. It communicates with the negative pressure operating port 3b through the pressure introducing passage 3d. Therefore, a negative pressure is applied to the outside through the air suction hole 2a in contact with the negative pressure operation port 3b, and the film 6 brought close to the air suction hole 2a is sucked by the negative pressure.

  Since the film 6 is conveyed in a certain direction, when the film 6 is sucked from the air suction hole 2a of the rotor 2, the film 6 and the rotor 2 are brought into close contact with each other and the rotor 2 rotates in the film conveying direction. As a result, a tensile force is applied to the film 6 to correct wrinkles.

  As the rotor 2 rotates, the air suction hole 2a in contact with the negative pressure operation port 3b is sequentially switched, and the air suction hole 2a in contact with the negative pressure introduction port 3c is also sequentially switched, so that the negative pressure in the negative pressure chamber 5 is interrupted. Without being interrupted, the film 6 is guided into the negative pressure introduction passage 3d and can be sucked from the air suction hole 2a of the rotor 2 without interruption. As a result, the rotation of the rotor 2 continues without interruption, and it is possible to continuously obtain the wrinkle stretching effect of the film 6.

  Further, since the rotor 2 rotates according to the conveyance of the film 6, the friction between the film 6 being conveyed and the wrinkle stretcher 1 is reduced, so that it is possible to suppress the generation of scratches on the film 6.

DESCRIPTION OF SYMBOLS 1 Wrinkle-stretching apparatus 2 Rotor 2a Air suction hole 3 Rotor support body 3a Shaft part 3b Negative pressure action port 3c Negative pressure introduction port 3d Negative pressure introduction path 4 Frame 5 Negative pressure chamber 6 Film

Claims (3)

A wrinkle stretching device for a film that sucks air from the upper side or the lower side of the film being conveyed,
With a substantially cylindrical rotor,
The substantially circular surface of the rotor is substantially perpendicular to the film width direction;
The rotor rotates about a rotor support;
A plurality of air suction holes are radially formed around the axis on a surface other than the substantially circular surface of the rotor,
The film wrinkle stretching device, wherein the volume of the air suction hole is reduced as the air suction hole is located on the end side in the film width direction.   2. The film according to claim 1, wherein the rotor has an R surface at an end portion, and an R value that is a curvature of the R surface is 1/20 or more of a diameter of a substantially circular surface of the rotor. Wrinkle-stretching device.   A method for producing a film, characterized in that the film wrinkle stretching apparatus according to claim 1 or 2 is used.

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