JP2015171766A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer which prevents air bubbles from adhering to a gravure roll with a simple structure.SOLUTION: A printer 10 includes: a gravure roll 20 rotatably held; an ink pan 40 which is disposed below the gravure roll and holds an ink to be supplied to the gravure roll; a doctor 30 which scrapes the excessive ink from the gravure roll; and a guide member 50 in which at least a part is disposed in the ink pan, the guide member 50 including an upper surface 51 which recovers the ink scraped from the gravure roll by the doctor. A first end part 51a of an upper surface of the guide member, which is located close to the gravure roll, is positioned higher than a second end part 52b of the upper surface of the guide member, which is separated from the gravure roll, in a vertical direction on a cross section perpendicular to a rotation axis of the gravure roll.

Description

  The present invention relates to a printer having a gravure roll, and more particularly to a printer capable of effectively preventing bubbles from adhering to a gravure roll.

  For example, as disclosed in Patent Document 1, printing presses having gravure rolls are widely used in various fields. This type of printing machine generally includes a gravure roll, an ink pan that holds ink, and a doctor that scrapes off excess ink from the gravure roll. The gravure roll has a cylindrical outer contour, and has a plate surface formed by a recess in a portion corresponding to the side surface of the cylinder. The gravure roll is held rotatably about the center axis of the cylinder, and a part of the plate surface passes through the ink held by the ink pan. At this time, ink is filled in the concave portion of the plate surface, and printing is performed by transferring the ink to the printing material. The doctor scrapes off excess ink on the printing plate and removes it from the printing plate. The ink scraped from the printing plate falls into the ink pan and is reused.

JP 2003-190857 A

  In such a printing machine, bubbles mixed in the ink in the ink pan may enter into the recesses of the plate surface of the gravure roll. In this case, there is a problem that the ink cannot be transferred to a position where the ink is desired to be transferred on the printed material, and there is also a problem that bubbles are transferred onto the printed material and burst on the printed material. As a method for coping with such a problem, it is conceivable that the ink in the ink pan circulates in the circulation path, and a deaeration module or a filter is provided in the circulation path. However, when such a method is used, it is necessary to significantly modify the existing printer. Patent Document 1 proposes ultrasonically vibrating a manifold that holds ink. The method disclosed in Patent Document 1 also requires significant renovation of existing equipment.

  The present invention has been made in consideration of the above points, and an object of the present invention is to provide a printing machine that can prevent bubbles from adhering to a gravure roll with a simple configuration.

  As a result of repeated earnest cases, the inventors of the present invention pay attention to the bubbles generated when the ink is scraped off by the doctor and the ink falls from the gravure roll to the ink pan. It has been found that the occurrence of defects can be effectively prevented. The present invention is based on such knowledge of the present inventors.

The printing press according to the present invention comprises:
A gravure roll held rotatably,
An ink pan disposed below the gravure roll and holding ink to be supplied to the gravure roll; and
A doctor that scrapes off excess ink from the gravure roll;
A guide member at least partially disposed within the ink pan, and
In a cross section orthogonal to the rotation axis of the gravure roll, a first end of the upper surface of the guide member on the side close to the gravure roll is a second end of the upper surface of the guide member on a side away from the gravure roll. It is located above the part in the vertical direction.

  In the printing press according to the present invention, in the cross section orthogonal to the rotation axis of the gravure roll, the upper surface of the guide member is gradually positioned upward from the second end toward the first end. It may be.

  In the printing press according to the present invention, in the cross section orthogonal to the rotation axis of the gravure roll, the upper surface of the guide member is in contact with the gravure roll on the side where the doctor of the gravure roll is provided in the vertical direction. You may make it cross | intersect with the extended straight line.

  In the printing machine according to the present invention, in the cross section orthogonal to the rotation axis of the gravure roll, the upper surface may be inclined at an angle of 10 ° or less with respect to the horizontal direction.

  In the printing press according to the present invention, the upper surface of the guide member may be connected to the ink pan at the second end.

  In the printing press according to the present invention, the guide member may further include a pair of side surfaces connected to the upper surface from both sides and extending from the upper surface.

  According to the present invention, it is possible to effectively prevent bubbles from adhering to the gravure roll without complicating the configuration of the printing press.

FIG. 1 is a perspective view showing a printing press for explaining an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the printing machine of FIG. 1 in a cross section orthogonal to the rotation axis of the gravure roll. FIG. 3 is a top view of the printing machine of FIG. 1 with the impression cylinder removed. FIG. 4 is a diagram corresponding to FIG. 2 for explaining a modification of the printing press.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product.

  As shown in FIGS. 1 and 2, the printing machine 10 includes a gravure roll 20, an impression cylinder 25, an ink pan 40, and a doctor 30.

  The gravure roll 20 is formed in a cylindrical shape. The gravure roll 20 has a plate surface 21 at a portion corresponding to the outer peripheral surface of a cylinder having an outer contour. The plate surface 21 is formed with a recess made of a bottomed hole, a groove, or the like. The shape and depth of the recess are appropriately determined in accordance with the pattern (pattern or pattern) to be printed, information (symbol or character, etc.) and the like. As shown in FIGS. 1 to 3, the gravure roll 20 is rotatably held with a central axis of a cylinder forming an outer contour as a rotation axis Ra.

  Similar to the gravure roll 20, the impression cylinder 25 is formed in a cylindrical shape. As shown in FIGS. 1 and 2, the impression cylinder 25 is rotatably held with a central axis of a cylinder having an outer contour as a rotation axis Rb. The rotation axis Rb of the impression cylinder 25 is parallel to the rotation axis Ra of the gravure roll 20. The impression cylinder 25 and the gravure roll 20 are positioned with respect to each other such that the outer peripheral surfaces of the cylinders forming the respective outer contours face each other.

  The ink pan 40 is a container that stores the ink 5, and includes a bottom surface 41 and a side surface 42 that extends from the bottom surface 41. As shown in FIG. 2, the ink pan 40 is disposed below the gravure roll 20. At least a part of the gravure roll 20 is positioned in the ink pan 40, and a part of the plate surface 21 of the gravure roll 20 is immersed in the ink 5 held in the ink pan 40. That is, the ink 5 is supplied to the plate surface 21 of the gravure roll 20 by rotating the gravure roll 20 in a state where the lower part of the gravure roll 20 is immersed in the ink 5 held in the ink pan 40. Note that the rotation axis Ra of the gravure roll 20 generally extends in the horizontal direction. For this reason, the ink 5 is supplied to the plate surface 21 of the gravure roll 20 so as to be substantially uniform at each position along the rotation axis Ra.

  The doctor 30 is a plate-like member extending along the rotation axis Ra of the gravure roll 20. The doctor 30 is supported so that the blade edge 31 is in contact with the plate surface 21 of the gravure roll 20. The doctor 30 scrapes off the excess ink 5 supplied to the plate surface 21 of the gravure roll 20 and removes the excess ink 5 from the gravure roll 20.

  In the printing press 10 having the above configuration, the ink 5 accommodated in the ink pan 40 is supplied to the plate surface 21 of the gravure roll 20 that rotates about the rotation axis Ra. The blade edge 31 of the doctor 30 abuts on the plate surface 21 of the gravure roll 20 and scrapes off excess ink 5 supplied on the plate surface 21. A web-like printed material W is supplied between the gravure roll 20 and the impression cylinder 25, and the ink 5 on the plate surface 21 is supplied to the printed material W. In this way, printing on the substrate W is continuously performed.

  The “printing” used in the present specification includes what are called coating, application, coating, and coating. Therefore, the “printing machine” is not distinguished from a device called a coating machine or a coater only because of a difference in name. The “ink” is not limited to a liquid containing a coloring material such as a pigment or a dye, but means a liquid to be printed such as a resin composition.

  By the way, if the air bubbles mixed in the ink 5 enter into the concave portion of the plate surface 21 of the gravure roll 20, a problem that the ink 5 cannot be transferred to the position where the ink 5 on the substrate W is desired to be transferred occurs. In addition, there is a problem that the bubbles are transferred onto the printing material W and burst on the printing material W. If the ink 5 is not transferred to a desired position, the position is visually recognized as a defect. Further, when the bubble bursts on the substrate W, the position becomes dirty.

  On the other hand, when the present inventors have intensively studied, in the printing press 10 described above, when the ink 5 scraped off by the doctor 30 falls on the ink 5 stored in the ink pan 40, the ink 5 It was confirmed that bubbles were generated inside. In addition, the inventors of the present invention have also confirmed that the bubbles are bubbles that have caused the above-described problems. And the guide member 50 is provided in the printing machine 10 demonstrated here. The guiding member 50 effectively restricts bubbles generated by the ink 5 being scraped off by the doctor 30 from approaching the gravure roll 20 in the ink pan 40. Hereinafter, the configuration and operation of the guide member 50 will be described.

  The guide member 50 is supported so that at least a part of the guide member 50 is disposed in the ink pan 40. In the illustrated example, the entire guide member 50 is disposed in the ink pan 40 as well shown in FIG. The guide member 50 is formed from a material having resistance to the ink 5. The guide member 50 can be formed using, for example, a Teflon (registered trademark) sheet. In the illustrated example, the guide member 50 is formed as a plate-like member. The doctor 30 has an upper surface 21 that receives the ink 5 scraped from the gravure roll 20. In the cross section shown in FIG. 2 orthogonal to the rotation axis Ra of the gravure roll 20, the first end portion (base end portion) 51 a on the side close to the gravure roll 20 on the upper surface 51 of the guide member 50 is a guide member. The upper surface 51 of the 50 is positioned above the second end portion (tip portion) 51b on the side away from the gravure roll 20 in the vertical direction.

  In the printing press 10 provided with such a guide member 50, the ink 5 scraped from the plate surface 21 by the doctor 30 falls into the ink stored in the ink pan 40 at a position above the upper surface 51 of the guide member 50. Even if the bubbles are formed, the bubbles are suppressed from approaching the plate surface 21 of the gravure roll 20 by the interposition of the first end portion 51a located above in the vertical direction. Thereby, generation | occurrence | production of the malfunction relevant to the bubble mentioned above can be suppressed effectively.

  Further, in the cross section shown in FIG. 2 orthogonal to the rotation axis Ra of the gravure roll 20, the upper surface 51 of the guide member 50 is gradually positioned upward from the second end 51b toward the first end 51a. It is preferable that Here, “being located gradually” is a concept including not only that the position of the upper surface 51 is always shifted upward, but also the case where the upper surface 51 extends in the horizontal direction in at least a part of the region. That is, the term “upper surface 51 is gradually located above” means that the position of the upper surface 51 does not shift downward in the vertical direction from the second end 51b to the first end 51a. Yes.

  In the printing press 10 provided with such a guide member 50, the ink 5 scraped from the plate surface 21 by the doctor 30 falls into the ink stored in the ink pan 40 at a position above the upper surface 51 of the guide member 50. Even if air bubbles are formed, the air bubbles are guided from the first end portion 51a side to the second end portion 51b side above the upper surface 51. Therefore, bubbles are effectively prevented from adhering to the plate surface 21 of the gravure roll 20. Thereby, generation | occurrence | production of the malfunction relevant to the bubble mentioned above can be suppressed effectively.

  In the illustrated example, in the cross section shown in FIG. 2 orthogonal to the rotation axis Ra of the gravure roll 20, the upper surface 51 of the guide member 50 is formed as a flat surface. Therefore, the upper surface 51 of the guide member 50 is continuously shifted upward from the second end portion 51b toward the first end portion 51a. Therefore, the bubbles are stably guided so as to be separated from the plate surface 21 of the gravure roll 20 above the upper surface 51 of the guiding member 50. This effectively prevents bubbles from adhering to the plate surface 21 of the gravure roll 20.

  In addition, as a result of confirmation by the inventors of the present invention, from the viewpoint of inducing the bubbles in the ink pan 40 to approach the plate surface 21 of the gravure roll 20 as described above, and further guiding the bubbles away from the plate surface 21. In the cross section shown in FIG. 2 orthogonal to the rotation axis Ra of the gravure roll 20, it is effective that the inclination angle of the upper surface 51 with respect to the horizontal direction is larger than 0 ° and not larger than 10 °.

  In the illustrated example, in the cross section shown in FIG. 2 orthogonal to the rotation axis Ra of the gravure roll 20, the upper surface 51 of the guide member 50 is on the side where the doctor 30 of the gravure roll 20 is provided. Intersects with an imaginary straight line la extending in the vertical direction. That is, in the cross section shown in FIG. 2, the first end 51 a of the upper surface 51 extends to a position closer to the gravure roll 20 than the virtual straight line la. According to such an example, the ink 5 scraped off from the plate surface 21 of the gravure roll 20 by the doctor 30 falls to a position above the upper surface 51 of the guide member 50 with a high probability. As a result, bubbles are generated in a region above the upper surface 51 of the guide member 50. As described above, the bubbles generated in this way are restricted from approaching the plate surface 21 of the gravure roll 20 and are further guided away from the plate surface 21. Thereby, it is possible to effectively prevent bubbles from adhering to the plate surface 21 of the gravure roll 20, and it is possible to effectively suppress the occurrence of defects related to the bubbles.

  Furthermore, from the viewpoint of collecting the ink 5 scraped off by the doctor above the guide member 50, the rotation axis Ra of the gravure roll 20 at the end of the guide member 50 on the side close to the gravure roll 20 is used. The along length lg is preferably longer than the length ld of the doctor 30 along the rotation axis Ra of the gravure roll 20.

  Further, in the illustrated example, the second end portion 51 b of the upper surface 51 of the guide member 50 is connected to the ink pan 40. Therefore, the bubbles on the upper surface 51 can be guided to a region far away from the plate surface 21 of the gravure roll 20. Thereby, it is possible to effectively prevent bubbles from adhering to the plate surface 21 of the gravure roll 20, and it is possible to effectively suppress the occurrence of defects related to the bubbles.

  Further, in the illustrated example, the guide member 50 further includes a pair of side surfaces 53, 53 connected to the upper surface 51 from both sides and extending from the upper surface 51. According to such a guiding member 50, it is possible to more effectively regulate the bubbles located above the guiding member 50 from approaching the plate surface 21 of the gravure roll 20. Thereby, it is possible to effectively prevent bubbles from adhering to the plate surface 21 of the gravure roll 20, and it is possible to effectively suppress the occurrence of defects related to the bubbles.

  In the illustrated example, as shown in FIG. 2, the upper end portion 53 a of the side surface 53 is located above the ink 5 accommodated in the ink pan 40. For this reason, it is possible to more effectively regulate the bubbles located above the guide member 50 from approaching the plate surface 21 of the gravure roll 20.

  In addition, it is preferable that the region surrounded by the guide member 50 and the side surface 42 of the ink pan 40 is not blocked from other portions in the ink pan 40. For example, in the illustrated example, as illustrated in FIG. 2, a gap is formed between the side surface 53 of the guide member 50 and the side surface 42 of the ink pan 40. Therefore, the ink 5 can stably flow out from the gap. Thereby, it is possible to prevent the supernatant portion of the ink 5 containing more bubbles from overflowing intensively from the region surrounded by the guide member 50 and the side surface 42 of the ink pan 40.

  According to the present embodiment as described above, the guide member 50 including the upper surface 51 for collecting the ink 5 scraped from the gravure roll 20 by the doctor 30 is at least partially positioned in the ink pan 40. , Provided. In the cross section shown in FIG. 2 orthogonal to the rotation axis Ra of the gravure roll 20, the first end 51 a on the side close to the gravure roll 20 on the upper surface 51 of the guide member 50 is the gravure roll on the upper surface 51 of the guide member 50. It is located above the second end portion 51b on the side away from 20 in the vertical direction. In the printing press 10 provided with such a guide member 50, the ink 5 scraped from the plate surface 21 by the doctor 30 is stored in the ink pan 40 at a position above the upper surface 51 of the guide member 50. Even if bubbles are formed by dropping, the bubbles are suppressed from approaching the plate surface 21 of the gravure roll 20 by the interposition of the first end 51a located above in the vertical direction. Thereby, generation | occurrence | production of the malfunction relevant to the bubble mentioned above can be suppressed effectively.

  As mentioned above, although this invention was demonstrated based on one embodiment illustrated, this invention is not limited to these embodiment, In addition, it can implement in a various aspect. For example, in the embodiment described above, an example in which a part of the gravure roll 20 is immersed in the ink 5 in the ink pan 40 and the ink 5 in the ink pan 40 is directly supplied to the gravure roll 20 has been described. I can't. For example, as shown in FIG. 4, the printing press 10 may further include a finisher roll 28.

  In the example shown in FIG. 4, the finisher roll 28 has a cylindrical outer contour, and is arranged so that the outer peripheral surface thereof faces the plate surface 21 of the gravure roll 20. The finisher roll 28 is rotatably supported with its central axis as a rotation axis Rc, and at least a part of the outer peripheral surface of the finisher roll 28 is immersed in the ink pan 40. Ink 5 is stored. The furnisher roll 28 rotates with the rotation of the gravure roll 20, whereby the ink 5 in the ink pan 40 is supplied to the plate surface 21 of the gravure roll 20 through the outer peripheral surface of the furnisher roll 28. Become so.

W Substrate 5 Ink 10 Printing machine 20 Gravure roll 21 Plate surface 25 Impression cylinder 28 Furnisher roll 30 Doctor 31 Cutting edge 40 Ink pan 41 Bottom surface 42 Side surface 50 Guide member 51 Upper surface 51a First end portion 51b Second end portion 53 Side surface 53a Upper end

Claims (6)

A gravure roll held rotatably,
An ink pan disposed below the gravure roll and holding ink to be supplied to the gravure roll; and
A doctor that scrapes off excess ink from the gravure roll;
A guide member at least partially disposed within the ink pan, and
In a cross section orthogonal to the rotation axis of the gravure roll, a first end of the upper surface of the guide member on the side close to the gravure roll is a second end of the upper surface of the guide member on a side away from the gravure roll. The printing press is located above in the vertical direction than the printing unit.   2. The cross-section perpendicular to the rotation axis of the gravure roll, the upper surface of the guide member is gradually positioned upward from the second end toward the first end. Printer.   In a cross section orthogonal to the rotation axis of the gravure roll, the upper surface of the guide member intersects with a straight line extending in a vertical direction in contact with the gravure roll on a side where the doctor of the gravure roll is provided. Item 3. A printing machine according to item 1 or 2.   The printing machine according to any one of claims 1 to 3, wherein the upper surface is inclined at an angle of 10 ° or less with respect to a horizontal direction in a cross section orthogonal to a rotation axis of the gravure roll.   The printing machine according to any one of claims 1 to 4, wherein the upper surface of the guide member is connected to the ink pan at the second end portion.   The printing machine according to any one of claims 1 to 5, wherein the guide member further includes a pair of side surfaces connected to the upper surface from both sides and extending from the upper surface.

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