JP6675236B2 - Gravure printing coating equipment - Google Patents

Description

  The present invention relates to a gravure printing coating apparatus for printing or coating a transfer liquid on a web.

  Conventionally, when the printing speed or coating speed is increased in gravure printing or coating using a plate cylinder having a large number of fine cells formed on the outer peripheral surface, the density of the web in the portion where the transfer liquid is transferred is increased. A phenomenon called so-called unevenness, which appears alternately in the rotation axis direction of the trunk, may occur. This phenomenon is considered to be one of the causes of the fact that the transfer liquid filled in each cell on the outer peripheral surface of the plate cylinder drops partially along the outer peripheral surface of the plate cylinder immediately before being transferred to the web. .

  In order to cope with this, for example, a gravure printing apparatus disclosed in Patent Document 1 is provided with an ink pan for storing ink, and a plate cylinder having a part of the outer peripheral surface immersed in the ink pan, and the outer periphery of the plate cylinder is rotated by a doctor blade. After the excess ink adhering to the surface is scraped off and removed by the rotation of the plate cylinder, the outer peripheral surface of the plate cylinder is brought into contact with the continuously transported web, so that the ink filled in each cell is transferred to the web. It is designed to transfer. Then, by bringing the contact portion of the doctor blade into contact with the outer peripheral surface of the plate cylinder closer to the contact portion of the plate cylinder with the web, and shortening the time until each cell passing the doctor blade transfers ink to the web, The ink filled in each cell is prevented from dripping along the outer peripheral surface of the plate cylinder.

JP 2007-253586 A

  By the way, as a cause of the unevenness as described above in the portion where the transfer liquid of the web is transferred, the transfer liquid adhering to the outer peripheral surface of the plate cylinder partially extends along the outer peripheral surface of the plate cylinder before passing through the doctor blade. The amount of transfer liquid filled in each cell after passing the doctor blade fluctuates in the direction of the rotation axis of the plate cylinder due to the dripping, and the amount of transfer liquid transferred to the web due to the fluctuation causes the amount of transfer liquid transferred to the web to be changed. It is also considered that the direction may vary, but Patent Document 1 does not take this into consideration at all.

  Further, in the configuration as in Patent Document 1 in which the contact portion of the doctor blade with the outer peripheral surface of the plate cylinder approaches the contact portion of the plate cylinder with the web, if the plate cylinder is to be replaced with one having a different diameter, another device is required. It is necessary to take measures such as changing the posture of the doctor blade so as not to come into contact with the portion, or making the doctor blade have a variable structure, which complicates the apparatus and increases the cost. Therefore, there is a demand to prevent the occurrence of unevenness without making the contact portion of the doctor blade with the outer peripheral surface of the plate cylinder as close as possible to the contact portion of the plate cylinder with the web.

  The present invention has been made in view of such a point, and it is an object of the present invention to provide a web in which a contact portion of a doctor blade with an outer peripheral surface of a plate cylinder is as close as possible to a contact portion of the plate cylinder with the web. It is an object of the present invention to provide a low-cost gravure printing coating apparatus capable of preventing occurrence of unevenness in a portion where the transfer liquid is transferred.

  In order to achieve the above object, the present invention is characterized by devising the structure of a doctor blade.

That is, a first contrivance is a liquid storage means for storing the transfer liquid, a plate cylinder which rotates with a part of the outer peripheral surface being immersed in the transfer liquid, and a plate cylinder which contacts the outer peripheral surface of the plate cylinder. Transfer liquid removing means for scraping and removing excess transfer liquid adhering to the outer peripheral surface by rotating the plate cylinder, wherein the transfer liquid is attached to the outer peripheral surface of the plate cylinder after being removed by the transfer liquid remover. The present invention relates to a gravure printing coating apparatus that transfers the transfer liquid to a continuously conveyed web. The transfer liquid removing means holds the first doctor blade and the second doctor blade each having flexibility, and the base end sides of the first doctor blade and the second doctor blade in an overlapping state. Blade holding means, wherein the second doctor blade is rotated more in the plate cylinder than the first doctor blade so that the tip of the second doctor blade protrudes from the tip of the first doctor blade. The first doctor blade and the second doctor blade are in contact with the outer peripheral surface of the plate cylinder, so that the second doctor blade is closer than the first doctor blade. The excess transfer liquid adhering to the outer peripheral surface of the plate cylinder is scraped off in a bent state .

Upper Symbol blade holding means includes a holding plate having flexibility undeflected than the second doctor blade, a pair of clamping members, the tip of the holding plate is protruded from the tip of the first doctor blade In this case, the holding plate is superimposed on a surface of the second doctor blade opposite to the first doctor blade, and the first doctor blade and the second doctor are held by the pair of holding members. The base end of the blade may be sandwiched together with the holding plate (second device).

The upper Symbol first doctor blade, a resin material, the second doctor blade is made of a metal material, it may be a (third device).

With the first contrivance, a space having a substantially triangular cross section is formed between the first and second doctor blades and the outer peripheral surface of the plate cylinder, and the plate is bent while the second doctor blade is bent more than the first doctor blade. The angle formed between the second doctor blade and the outer peripheral surface of the plate cylinder becomes acute by contacting the outer peripheral surface of the cylinder. When printing or coating is performed in this state, first, the transfer liquid adhering to the outer peripheral surface of the plate cylinder is scraped by the rotation operation of the plate cylinder and pushed into each cell by the first doctor blade. The transfer liquid adhering to the outer peripheral surface of the plate cylinder that has not been scraped by one doctor blade advances to the contact portion between the second doctor blade and the outer peripheral surface of the plate cylinder. Then, a liquid pool is generated near the contact portion of the second doctor blade with the outer peripheral surface of the plate cylinder due to the transfer liquid that has not passed through the second doctor blade. At this time, the transfer liquid that does not pass through the second doctor blade tends to move along the second doctor blade in a direction away from the contact portion of the second doctor blade with the outer peripheral surface of the plate cylinder. In the position, the second doctor blade is close to the first doctor blade, so that the transfer liquid moves back along the first doctor blade to the outer peripheral surface side of the plate cylinder, adheres to the outer peripheral surface of the plate cylinder, and The two doctor blades merge with the transfer liquid moving toward the contact portion with the outer peripheral surface of the plate cylinder. In other words, the liquid pool generated in the vicinity of the contact portion of the second doctor blade with the outer peripheral surface of the plate cylinder is hardly settled at one place by circulating while rotating, and the amount of liquid pool is reduced by the circulation operation. Since it becomes easy to be substantially uniform in the axial direction, the amount of the transfer liquid filled in each cell after passing through the second doctor blade can be made substantially uniform in the rotational axis direction of the plate cylinder, and the transfer liquid on the web was transferred. Non-uniformity can be prevented from occurring in the portion. Further, it is not necessary to make the contact portion of the second doctor blade in contact with the outer peripheral surface of the plate cylinder close to the contact portion of the plate cylinder with the web, and it is not necessary to make the device a complicated structure, so that the device can be manufactured at low cost.

According to the second contrivance, the amount of deflection near the contact portion of the second doctor blade with the outer peripheral surface of the plate cylinder increases, and the vicinity of the contact portion of the second doctor blade with the outer peripheral surface of the plate cylinder becomes closer to the outer peripheral surface of the plate cylinder. As a result, the angle formed between the vicinity of the contact portion of the second doctor blade with the outer peripheral surface of the plate cylinder and the outer peripheral surface of the plate cylinder becomes smaller, and the first and second doctor blades and the outer peripheral surface of the plate cylinder become smaller. The space formed between the surface and the surface becomes smaller. Therefore, the circulation cycle of the transfer liquid can be accelerated in the liquid pool generated in the vicinity of the contact portion of the second doctor blade with the outer peripheral surface of the plate cylinder, and the amount of the liquid pool can be further uniform in the rotation axis direction of the plate cylinder. It becomes easy to become.

According to the third device, when the first and second doctor blades are brought into contact with the outer peripheral surface of the plate cylinder, a space formed between the first and second doctor blades and the outer peripheral surface of the plate cylinder becomes the second doctor blade. An ideal shape in which the transfer liquid easily circulates in the liquid pool generated near the contact portion of the blade with the outer peripheral surface of the plate cylinder is obtained, and the uniformity of the liquid pool in the direction of the rotation axis of the plate cylinder is reliably achieved. be able to.

1 is a schematic front view of a gravure printing apparatus according to an embodiment of the present invention. It is the A section enlarged view of FIG. FIG. 3 is an enlarged view of a portion B in FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is essentially merely an example.

  FIG. 1 shows a gravure printing apparatus 1 as a gravure printing coating apparatus according to an embodiment of the present invention. The gravure printing apparatus 1 includes a plate cylinder 2 for performing gravure printing on a web 10 such as a plastic film, and a large number of fine cells (not shown) are formed on an outer peripheral surface 2 a of the plate cylinder 2. ing.

  An impression cylinder 3 for pressing the web 10 against the plate cylinder 2 is disposed above the plate cylinder 2, and the web 10 is sandwiched between the outer peripheral surface 2a of the plate cylinder 2 and the outer peripheral surface 3a of the impression cylinder 3. By rotating the plate cylinder 2 and the impression cylinder 3, the ink 8 filled in the cells on the outer peripheral surface 2a is transferred onto the web 10 while the web 10 is continuously conveyed so as to be substantially V-shaped in a front view. It is supposed to.

  A furnisher roll 4 having a smaller diameter than the plate cylinder 2 is rotatably provided on one side of the plate cylinder 2, and the outer peripheral surface 4 a of the finisher roll 4 is provided on the outer peripheral surface 2 a of the plate cylinder 2. While being in contact with each other, the plate cylinder 2 rotates in the opposite direction.

  Between the upper portions of the outer peripheral surfaces 2a, 4a of the plate cylinder 2 and the finisher roll 4, a pair of substantially triangular resin side plates 5 are arranged so as to straddle the plate cylinder 2 and the finisher roll 4. They are spaced apart in the direction of the body rotation axis.

  The plate cylinder 2, the finisher roll 4, and both side plates 5 constitute a liquid reservoir 9 (liquid reservoir means) for storing ink 8 to be supplied to the outer peripheral surface 2a of the plate cylinder 2. Ink 9 is supplied from an ink supply device (not shown).

  That is, a part of the outer peripheral surface 2 a of the plate cylinder 2 is immersed in the liquid reservoir 9.

  Below the plate cylinder 2 and the finisher roll 4, an ink pan 6 for collecting the ink 8 falling from the outer peripheral surface 2a of the plate cylinder 2 and the ink 8 overflowing from the liquid reservoir 9 is provided.

  On the downstream side of the finisher roll 4 in the rotation direction of the plate cylinder 2 and on the other side of the plate cylinder 2, an extra portion that comes into contact with the outer peripheral surface 2 a of the plate cylinder 2 and adheres to the outer peripheral surface 2 a. An ink removing unit 7 (transfer liquid removing means) for scraping and removing the ink 8 by rotating the plate cylinder 2 is provided.

  As shown in FIGS. 2 and 3, the ink removing unit 7 includes a first resin-made plate-shaped doctor blade 7a having flexibility and extending in the direction of the rotation axis of the plate cylinder 2, and the first doctor blade 7a. A metal second doctor blade 7b, which is disposed downstream of the plate cylinder 2 in the rotation direction of the plate cylinder 2 and extends in the direction of the rotation axis of the plate cylinder 2 and has a flexible shape; and the first and second doctor blades And a blade holder 7c (blade holding means) for holding the blades 7a and 7b.

  The second doctor blade 7b is designed to bend more than the first doctor blade 7a, and is superimposed on the first doctor blade 7a such that the tip protrudes from the tip of the first doctor blade 7a.

  At the tip of the second doctor blade 7b, a thin portion 7f having a smaller thickness than other portions of the second doctor blade 7b is formed, and the thin portion 7f is formed by the first doctor of the second doctor blade 7b. Since the opposite surface of the blade 7a is recessed in a step shape, its thickness is smaller than that of the other portion of the second doctor blade 7b.

  The blade holder 7c includes a flexible plate-shaped resin holding plate 7d extending in the rotation axis direction of the plate cylinder 2, and the holding plate 7d does not bend from the second doctor blade 7b. It is designed to be.

  The holding plate 7d is superimposed on the surface of the second doctor blade 7b on the opposite side of the first doctor blade 7a so that the tip does not protrude from the tip of the first doctor blade 7a.

  The blade holder 7c includes a pair of holding members 7e having a block shape for holding substantially half of the base side of the superposed first and second doctor blades 7a and 7b together with the holding plate 7d.

  When removing the excess ink 8 adhering to the outer peripheral surface 2a of the plate cylinder 2, the ink removing unit 7 deflects the first and second doctor blades 7a, 7b while bending the respective tips. A space S1 having a substantially triangular cross section is formed between the first and second doctor blades 7a and 7b and the outer peripheral surface 2a of the plate cylinder 2 so as to be brought into contact with the outer peripheral surface 2a of the plate cylinder 2 at the same time. ing. The angle formed between the second doctor blade 7b in the space S1 and the outer peripheral surface 2a of the plate cylinder 2 is determined in such a manner that the second doctor blade 7b is bent more than the first doctor blade 7a. An acute angle is formed by contacting the surface 2a.

  Here, the removal of the ink 8 attached to the outer peripheral surface 2a of the plate cylinder 2 by the ink removing unit 7 will be described in detail.

  First, when the operator operates the gravure printing apparatus 1, the ink 8 is supplied to the liquid reservoir 9 from an ink supply device (not shown), and the plate cylinder 2, the impression cylinder 3, and the finisher roll 4 start rotating. Then, as shown in FIG. 1, portions of the outer peripheral surface 2 a of the plate cylinder 2 immersed in the liquid reservoir 9 sequentially move toward the ink removing unit 7.

  When the portion of the outer peripheral surface 2a of the plate cylinder 2 to which the ink 8 has adhered reaches the ink removing unit 7, first, as shown in FIG. 3, the first doctor blade 7a adheres to the outer peripheral surface 2a of the plate cylinder 2. The ink 8 is scraped off by the rotation of the plate cylinder 2 and pushed into each cell.

  Thereafter, the ink 8 that has not been scraped off by the first doctor blade 7a and adheres to the outer peripheral surface 2a of the plate cylinder 2 advances to the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2. Then, a liquid pool R1 is generated near the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2 due to the ink 8 that has not passed through the second doctor blade 7b. At this time, the ink 8 that does not pass through the second doctor blade 7b is moved away from the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2 (indicated by an arrow X1 in FIG. 3). 7b, but at a position distant from the contact portion T1, the second doctor blade 7b is close to the first doctor blade 7a, so that the ink 8 is transferred along the first doctor blade 7a. 2 and returns to the outer peripheral surface 2a side of the plate cylinder 2, and joins the ink 8 which adheres to the outer peripheral surface 2a of the plate cylinder 2 and moves toward the contact portion T1.

  That is, the liquid pool R1 generated in the vicinity of the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2 stagnates at one place by circulating while rotating as shown by the arrow X2 in FIG. Since the amount of the liquid pool R1 is likely to be substantially uniform in the direction of the rotation axis of the plate cylinder 2 due to the circulation operation, the amount of ink 8 filled in each cell after passing through the second doctor blade 7b is reduced. 2 can be made substantially uniform in the direction of the rotation axis, and unevenness can be prevented from occurring in the portion of the web 10 where the ink 8 has been transferred.

  If the second doctor blade 7b is arranged in parallel to the first doctor blade 7a to remove the ink 8 attached to the outer peripheral surface 2a of the plate cylinder 2, as shown by the imaginary line in FIG. As shown by the arrow X3, even when the ink 8 moves along the second doctor blade 7b in the direction away from the contact portion T1 in the liquid pool R1, the second doctor blade 7b is moved away from the contact portion T1. Since the first doctor blade 7a is away from the first doctor blade 7a, the first doctor blade 7a cannot smoothly guide the ink 8 to the contact portion T1, and the ink 8 tends to stagnate at one position near the contact portion T1. Therefore, even if the amount of the liquid pool R1 is not uniform in the direction of the rotation axis of the plate cylinder 2, the state is maintained as it is, and it is difficult to suppress the occurrence of unevenness in the portion of the web 10 where the ink 8 is transferred. .

  As described above, in the embodiment of the present invention, the amount of the ink 8 filled in each cell after passing through the second doctor blade 7b can be made substantially uniform in the direction of the rotation axis of the plate cylinder 2, and the ink 8 of the web 10 is transferred. Irregularities can be prevented from being generated in the portion where the light emission has occurred.

  Further, it is not necessary to make the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2 close to the contact portion T2 of the plate cylinder 2 with the web 10, so that the gravure printing apparatus 1 needs to have a complicated structure. Therefore, the gravure printing apparatus 1 can be manufactured at low cost.

  Furthermore, since the holding plate 7d increases the amount of bending of the second doctor blade 7b near the contact portion T1 with the outer peripheral surface 2a of the plate cylinder 2, the contact portion of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2 is increased. The vicinity of T1 comes closer to the outer peripheral surface 2a of the plate cylinder 2. Therefore, the angle formed between the vicinity of the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2 and the outer peripheral surface 2a of the plate cylinder 2 is reduced, and the first and second doctor blades 7a are formed. , 7b and the outer peripheral surface 2a of the plate cylinder 2, the space S1 is reduced, so that the liquid pool R1 generated near the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2 is formed. The circulation cycle of the ink 8 can be advanced, and the amount of the liquid pool R1 tends to be more uniform in the direction of the rotation axis of the plate cylinder 2.

  In addition, since the first doctor blade 7a is formed of a resin material and the second doctor blade 7b is formed of a metal material, the first and second doctor blades 7a and 7b are brought into contact with the outer peripheral surface 2a of the plate cylinder 2. In this case, the space S1 formed between the first and second doctor blades 7a and 7b and the outer peripheral surface 2a of the plate cylinder 2 is near the contact portion T1 of the second doctor blade 7b with the outer peripheral surface 2a of the plate cylinder 2. In this case, the ink 8 is easily circulated in the liquid pool R1 generated during the printing, and the amount of the liquid pool R1 in the direction of the rotation axis of the plate cylinder 2 can be made uniform.

  In the embodiment of the present invention, the first doctor blade 7a is formed of a resin material, and the second doctor blade 7b is formed of a metal material. However, the present invention is not limited to this. 7b may be formed of other materials as long as it can bend.

  Further, in the embodiment of the present invention, the holding plate 7d is overlapped on the second doctor blade 7b, but it is not essential to overlap the holding plate 7d.

  In addition, the ink removing unit 7 applied to the gravure printing apparatus 1 in the embodiment of the present invention can be used as a coating liquid removing unit in a coating apparatus for coating the web 10.

  INDUSTRIAL APPLICABILITY The present invention is suitable for a gravure printing coating apparatus for printing or coating a transfer liquid on a web.

1 Gravure printing equipment (gravure printing coating equipment)
2 Plate cylinder 2a Outer peripheral surface 7 Ink removing unit (transfer liquid removing means)
7a first doctor blade 7b second doctor blade 7c blade holder (blade holding means)
7d Holding plate 7e Holding member 8 Ink (transfer liquid)
9 Liquid reservoir (liquid reservoir means)
10 Web

Claims (3)

Liquid storage means for storing a transfer liquid;
A plate cylinder that rotates with a part of the outer peripheral surface immersed in the transfer liquid,
Transfer liquid removing means for scraping and removing excess transfer liquid adhering to the outer peripheral surface by contacting the outer peripheral surface of the plate cylinder by rotating the plate cylinder;
A gravure printing coating apparatus that transfers the transfer liquid adhering to the outer peripheral surface of the plate cylinder to a continuously conveyed web after being removed by the transfer liquid removing means,
The transfer liquid removing means,
A first doctor blade and a second doctor blade each having flexibility;
Blade holding means for holding the base sides of the first doctor blade and the second doctor blade in an overlapping state,
Has,
The second doctor blade is disposed downstream of the first doctor blade in the rotation direction of the plate cylinder with respect to the first doctor blade so that the tip of the second doctor blade protrudes from the tip of the first doctor blade. In a state where both ends of the first doctor blade and the second doctor blade are in contact with the outer peripheral surface of the plate cylinder, and the second doctor blade is more bent than the first doctor blade, A gravure printing coating apparatus for scraping off excess transfer liquid adhering to the outer peripheral surface of a plate cylinder . The gravure printing coating device according to claim 1,
The blade holding means,
A holding plate having flexibility that does not bend more than the second doctor blade ;
A pair of holding members,
With
The holding plate is superimposed on a surface of the second doctor blade opposite to the first doctor blade so that a tip of the holding plate does not protrude from a tip of the first doctor blade. A gravure printing coating apparatus , wherein the holding members hold the base ends of the first doctor blade and the second doctor blade together with the holding plate . The gravure printing coating device according to claim 1 or 2,
The first doctor blade is made of a resin material,
The second doctor blade is made of a metal material.

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