JP2008246682A - Embossed film and embossing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic resin film subjected to embossing so as to prevent the shift of the edge surface of the thermoplastic resin film taken up after embossing is applied to the thermoplastic resin film and the occurrence of a product defect caused by the shift of the edge surface of the taken-up film, and an embossing apparatus. <P>SOLUTION: This embossed film is characterized in that projections are provided on both upper and under sides of the film of the side edge parts of the film and the projections on the surface of the film and the projections on the back of the film are provided at the positions not overlapping each other within the planes of the film. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thermoplastic resin film and an embossing apparatus. More specifically, after embossing the thermoplastic resin film, the end surface of the wound film is not displaced, and the embossed thermoplastic resin film and the embossing device prevent the product defects from occurring. About.

  Conventionally, various film molded products using a thermoplastic resin as a raw material are known. Among them, polyester films, especially polyethylene terephthalate films, are excellent in terms of mechanical properties, electrical properties, chemical resistance, dimensional stability, etc., so they are for magnetic tapes, capacitors, packaging materials, plate making, electrical It is used as a base material in various fields such as insulating materials, beverage can lamination, and photographic film. The thermoplastic resin raw material is discharged from a die by, for example, a melt extrusion method and cooled and solidified by a drum or the like. Thereafter, the film is biaxially stretched at an appropriate temperature and stretch ratio, and wound into a roll with a winder. At the time of winding, the end face of the film wound as an intermediate product may be displaced or the film may be wrinkled depending on the amount of air to be wound, which may cause a winding shape defect.

  Conventionally, as a countermeasure for these, there has been known a method of embossing a film side edge by an embossing ring having a large number of protrusions, forming protrusions on the film, and winding the film (for example, Patent Document 1, Patents). Reference 2). Also, in this post-process, there is a process of winding to the width and length required by the customer, that is, a slit process. In this process as well, embossing is performed on the side edge of the film, and a film is formed with a protrusion and wound. It has been known.

By these methods, when the film is wound under appropriate winding conditions, the air trapped on the roll can be appropriately removed, and the film is effective in preventing wrinkles. However, the film end face shift that occurs during winding and the film end face shift that occurs during the transportation of the product roll are not completely perfect because there is too much air entrainment, although some effects are recognized. These increased costs due to deterioration in quality and yield.
JP-A-7-108603 JP-A-9-124199

  The object of the present invention is to solve the above-mentioned problems of the prior art, and after embossing the thermoplastic resin film, the end face of the wound film does not shift, and the product defects caused thereby An object of the present invention is to provide an embossed thermoplastic resin film and an embossing apparatus for a thermoplastic resin film which are prevented from being generated.

The present invention employs the following configuration in order to solve the above-described problems. That is,
(1) A film having projections on both sides of the film at the film side edge, and having projections on the film surface and projections on the back side of the film at positions where they do not overlap in the film plane.

  (2) The above-mentioned (1), wherein a plurality of protrusions on the film surface have a plurality of protrusions in the film width direction on the film side edge, and a protrusion on the film back surface has between the protrusions in the film width direction on the film surface. Film.

  (3) The film according to (1) or (2), wherein a distance H between adjacent protrusions in the film width direction satisfies the following formula (1).

0 (mm) ≦ distance H (mm) ≦ 1.5 (mm) between adjacent protrusions (1)
(4) In an embossing apparatus for forming embossed patterns of protrusions on both sides of the film at the film side edge, the protrusions on the film surface and the protrusions on the back surface of the film are formed at positions that do not overlap in the film surface. Embossing device.

  (5) The embossing apparatus according to (4), wherein the distance H between adjacent protrusions in the film width direction satisfies the following formula (2).

  0 (mm) ≦ distance H (mm) ≦ 1.5 (mm) between adjacent protrusions (2)

  According to the embossing thermoplastic resin film and the thermoplastic resin film embossing apparatus of the present invention, there is no film end face deviation that occurs when winding after embossing and film end face deviation that occurs during transportation. ) No scratches on the film surface due to film edge displacement. (II) The film end face misalignment due to film end face misalignment is eliminated and the yield is improved. These effects make it possible to provide a high-quality film and further improve productivity.

  Hereinafter, the present invention will be described in more detail.

  The embossed thermoplastic resin film of the present invention is formed by forming embossed patterns of protrusions on both sides of the film on both sides of the traveling thermoplastic resin film, and the protrusions on both sides of the film are on the film surface. It is the embossed thermoplastic resin film which has a position which does not overlap inside.

  The protrusions on both the front and back surfaces of the film are alternately formed at positions where the protrusions on the film surface and the film back surface do not overlap in the film width direction of the side edge of the film. It is preferable that the side edge part of the said film is a part from the both ends of a film to about 30 mm width.

  Moreover, the embossing apparatus of this invention is the embossing apparatus for forming the embossed pattern of the protrusion along a film conveyance direction in the side edge part of a thermoplastic resin film. And an embossing process so that the projections on both sides of the film do not overlap the film surface, and the embossing ring and the metal roll that press the thermoplastic resin film sandwich the film up and down (or It is an embossing apparatus for thermoplastic resin film, which is disposed on the left and right sides, and on the downstream side thereof, the embossing ring and the metal roll are disposed in the opposite vertical (or left and right) positions.

  The thermoplastic resin film in the present invention is not particularly limited, but representative examples include polyesters such as polyethylene terephthalate, polyamides such as polyethylene-2, 6-naphthalate, polypropylene, and nylon-6, polyphenylin sulfide, and the like. It is. Hereinafter, the thermoplastic resin film is simply referred to as a film.

  Conventionally, when embossing a film, it is common to press the film between an embossing ring with a protrusion on the outer periphery of the ring and a rubber roll or metal roll to form an embossing ring protrusion. there were. However, as described above, this method did not provide a satisfactory effect on the deviation of the film end face.

  As a result of investigating the cause of the deviation of the film end face in the conventional embossing method, the inventors have adjusted the winding conditions (for example, surface pressure and tension), and on the roll by the embossed protrusions. The focus was on preventing wrinkling and misalignment of the film by controlling the amount of air between the wound films. However, with these, even if the winding surface pressure and the winding tension are accurately adjusted due to the thickness and unevenness of the film and the surface roughness of the film, it is difficult to completely prevent the end face deviation.

  Therefore, as a result of earnestly examining the method for preventing the deviation of the film end face without being greatly affected by the accuracy, the present inventors have formed the protrusions of the embosses alternately on the front and back sides of the film in the film width direction. Thus, when the film is wound on a roll, the stacked protrusions interfere with each other, and the present invention has been achieved on the basis of the idea that it is effective for preventing the film from shifting. .

  FIG. 1 is a side view showing an example of a film embossing apparatus of the present invention. In FIG. 1, 1 is a film, 2 is an upstream embossing ring, 3 is an upstream nip roll, 4 is a downstream embossing ring, 5 is a downstream nip roll, and 6 is a wound film.

  FIG. 2 is a cross-sectional view of the wound film 6 in the film width direction, 7 is a winding core, and 8 is a protrusion.

  FIG. 3 is an enlarged cross-sectional view of the protruding portion 8, where W1 is the width of the protruding portion in the film width direction, H is the width direction of the film, and between adjacent protruding portions of the film laminated when the film is wound on the roll. (That is, the distance between adjacent front surface protrusions and back surface protrusions in the film width direction), and t indicates the height of the protrusions.

  The conveyed film 1 is provided with an upstream embossing ring 2 and an upstream nip roll 3, and in this drawing, an upstream embossing ring 2 having an embossed protrusion formed on the back side of the film is disposed. Thereafter, the downstream embossing ring 4 and the downstream nip roll 5 are arranged with the downstream embossing ring 4 having an embossed protrusion formed on the film surface side in the drawing. Here, even if the upstream embossing ring 2 and the upstream nip roll 3 are interchanged in the positions of the downstream embossing ring 4 and the downstream nip roll 5, the order of the protrusions formed on the film surface may be reversed. Further, there is a method in which the upstream embossing ring 2 and the downstream embossing ring 4 are pressed to form protrusions on both the front and back surfaces of the film at the same time.

  However, as shown in FIG. 2, the upstream embossing ring 2 and the downstream embossing ring are such that the protrusions due to the embossing are in the film width direction, and the protrusions on the film surface and the film backside are not overlapped in the film surface. It is important that 4 is arranged.

  In addition, in this figure, the number of rows of projections is 2 rows on the upper surface of the film and 3 rows on the lower surface. However, it is necessary to have a plurality of projections on the film side edge in the film width direction. It is preferable to have a part between the protrusion parts of the film surface in the film width direction, ie, between the adjacent protrusion parts of the film surface in the film width direction.

  In the illustrated example, a metal roll is used as the nip roll, but the same effect can be obtained even in the case of a rubber roll.

  Furthermore, since the distance between the films wound by the projections on both the film surface and the film back surface is regulated, it is not necessary to control the projection height with high accuracy as in the conventional case. In other words, when forming protrusions on the film only from one side of the film, unevenness of accuracy such as embossing ring processing accuracy, embossing ring and nip roll mounting accuracy, and uneven contact pressure becomes unevenness of protrusions formed on the film. Is directly reflected in the distance between the films in the embossed portion. However, according to the present invention, since the projections are formed on both sides of the film, the accuracy of one side is poor. For example, even if the height of one projection is low, the distance between the films is regulated by the other one projection. Therefore, it becomes possible to control the air amount between the films stably. Thereby, the shift | offset | difference of the film during winding and after winding is reduced.

  Furthermore, as shown in FIG. 2, since the protrusions of the film are alternately formed on the film surface and the film back surface, the protrusions interfere with each other in the film width direction, thereby preventing displacement.

  Further, in the protrusions, when the distance H between the protrusions adjacent in the film width direction is 0 mm, the protrusions alternately interfere with each other without any gap, so that no deviation of the product end surface occurs. If the distance H between adjacent protrusions is less than 0, the protrusions of the laminated films are less likely to interfere with each other, and the film is likely to be displaced. Also, if the distance H between adjacent protrusions in the film width direction exceeds 1.5 mm, the film end face will be misaligned, the product may be scratched, and the quality may deteriorate. It is preferable that it is 5 mm or less.

  Therefore, in the present invention, it is important that the distance H between adjacent protrusions in the film width direction is 0 (mm) or more, and further, the distance H between adjacent protrusions in the film width direction. Is a film satisfying the following formula (1).

0 (mm) ≦ H (mm) ≦ 1.5 (mm) (1)
In order to form such a film, it is important to use an embossing apparatus in which the distance H between adjacent protrusions in the film width direction is 0 (mm) or more. It is preferable to use a filling embossing device.

0 (mm) ≦ H (mm) ≦ 1.5 (mm) (2)
FIG. 4 is a plan view in the width direction of the wound film. As shown in FIG. 4, protrusions are continuously formed in the film conveying direction at intervals. In addition, it is preferable that the space | interval D2 between the protrusion parts in the film conveyance direction of FIG.

  The numerical ranges of the width W1 of the protrusion in the film width direction and the distance D1 between the protrusions in the film width direction are preferably 0.2 to 1.0 mm and 3.2 to 4.0 mm, respectively.

  In addition, even if the shape of the protrusion is different from a trapezoidal shape such as a triangle or a quadrangle, the same effect can be expected in preventing the deviation of the film edge.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples.

Example 1
In the apparatus shown in FIG. 1, a polyethylene terephthalate film is used to wind a film having a film thickness of 200 μm, a film width of 1200 mm, a film conveyance speed of 100 m / min, a contact roll pressing pressure of 70 N / m, and a film winding tension of 320 N / m. In the cutting conditions, the width W1 of the protrusions in the film width direction is 0.4 mm, the distance H between adjacent protrusions in the film width direction is 3 mm, and as shown in FIG. Processed protrusions on both sides of the film, wound up 1500 m with a protrusion height of 3-5 μm, and confirmed deviation of the end, but it was suppressed to 1 mm or less, although deviation of the edge after winding occurred. did it. In addition, the scratch on the part could be suppressed to 0.5 mm or less.
(Example 2)
In the apparatus shown in FIG. 1, a polyethylene terephthalate film is used, and the film thickness is 200 μm, the film width is 1200 mm, the film transport speed is 100 m / min, the contact roll pressing pressure is 70 N / m, and the film winding tension is 320 N / m. Under the removal conditions, the width W1 of the protrusions in the film width direction is 0.4 mm, the distance H between adjacent protrusions in the film width direction is 0 mm, and as shown in FIG. Processed protrusions on both sides of the film, wound up 1500m with a protrusion height of 3-5μ, and confirmed misalignment of the edges, but the misalignment of the edges was incapable of being measured during and after winding. It was ready. Moreover, the wound roll was packed and transported by truck, but there was no deviation at the end, and there was no scratch due to the end deviation.
(Example 3)
In the apparatus shown in FIG. 1, a polyethylene terephthalate film is used to wind a film having a film thickness of 200 μm, a film width of 1200 mm, a film conveyance speed of 100 m / min, a contact roll pressing pressure of 70 N / m, and a film winding tension of 320 N / m. Under the removal conditions, the width W1 of the projections in the film width direction is 0.4 mm, the distance H between adjacent projections in the film width direction is 1.5 mm, and as shown in FIG. Processed protrusions on both sides of the film as 3 rows, wound up 1500m with protrusion height 3-5μ, and confirmed edge misalignment, but it was not possible to measure the edge misalignment during and after winding It was all right. Moreover, the wound roll was packed and transported by truck, but there was no deviation at the end, and there was no scratch due to the end deviation.

Example 4
In the apparatus shown in FIG. 1, using a polyethylene terephthalate film, the film thickness is 200 μm, the film width is 1200 mm, the film transport speed is 100 m / min, the contact roll is not pressed, and the film winding tension is 420 N / m. The width W1 of the protrusions in the width direction is 0.4 mm, the distance H between adjacent protrusions in the film width direction is 1.5 mm, and as shown in FIG. The protrusions were processed, the height of the protrusions was 3 to 5 μ, and the film was wound up by 1500 m, and the deviation of the ends was confirmed. However, the deviation of the ends was uniform even during winding and after winding. Moreover, the wound roll was packed and transported by truck, but there was no deviation of the end part and there was no scratch due to the end part deviation.

(Comparative Example 1)
In the apparatus shown in FIG. 1, using a polyethylene terephthalate film, the film thickness is 200 μm, the film width is 1200 mm, the film transport speed is 100 m / min, the contact roll pressing pressure is 70 N / m, and the film winding tension is 320 N / m. , The width W1 of the protrusion in the film width direction was 0.4 mm, and only five rows of protrusions were processed on one side of the film, the protrusion height was 3 to 5 μ, and the film was wound up by 1500 m, and the deviation of the end was confirmed. Although there was no deviation during winding during acceleration and constant speed, a deviation occurred about 2 mm at the end during deceleration, and a scratch of 0.5 to 1 mm occurred at that portion.

(Comparative Example 2)
In the apparatus shown in FIG. 1, using a polyethylene terephthalate film, the film thickness is 200 μm, the film width is 1200 mm, the film transport speed is 100 m / min, the contact roll is not pressed, and the film winding tension is 420 N / m. The width W1 of the protrusions in the width direction was set to 0.4 mm, and only five rows of protrusions were processed on one side of the film. The protrusions were wound up by 1500 m with a height of 3 to 5 μm, and the deviation of the ends was confirmed. Even at a constant speed, a deviation of about 1 mm occurred at the end portion, and further, a deviation of about 5 mm occurred at the time of deceleration, and many scuffing scratches of around 2 mm occurred at that portion.

  The present invention can be applied not only to an embossing device that prevents a film end face shift occurring during winding or during transportation, but also to an embossing device for a sheet-like material that can be wound. The range is not limited to these.

It is a side view which shows an example of the embossing apparatus of the thermoplastic resin film of this invention. It is a perspective view which shows an example of the film processed with the embossing apparatus of the thermoplastic resin film of this invention, and shows sectional drawing of the width direction of a part film. It is an enlarged view of the projection part 8 in sectional drawing of a film width direction. It is a figure which shows an example of the film processed with the embossing apparatus of the thermoplastic resin film of this invention, and shows the top view of the width direction of a part film.

Explanation of symbols

1: Film 2: Upstream embossing ring 3: Upstream nip roll 4: Downstream embossing ring 5: Downstream nip roll 6: Rolled film 7: Winding core 8: Protruding portion W1: Protruding portion width W2 in the film width direction: Width of projections in the film conveyance direction H: Distance between projections in the film width direction t: Height of projections D1: Interval between projections in the film width direction D2: Interval between projections in the film conveyance direction

Claims (5)

  A film having protrusions on both front and back sides of a film side edge, and having a protrusion on the film surface and a protrusion on the back of the film at a position where they do not overlap in the film surface.   2. The film according to claim 1, wherein a plurality of protrusions on the film surface are provided in the film width direction on the film side edge, and a protrusion on the film back surface is provided between the protrusions in the film width direction on the film surface. . The film according to claim 1 or 2, wherein a distance H between adjacent protrusions in the film width direction satisfies the following formula (1).
0 (mm) ≦ H (mm) ≦ 1.5 (mm) (1)   In an embossing apparatus for forming embossed patterns of protrusions on both sides of the film at the film side edge, the embossing is characterized in that the protrusions on the film surface and the protrusions on the back surface of the film are formed at positions that do not overlap in the film surface. Processing equipment. The embossing apparatus according to claim 4, wherein a distance H between adjacent projecting portions in the film width direction satisfies the following formula (2).
0 (mm) ≦ H (mm) ≦ 1.5 (mm) (2)

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