JP4208066B2 - Printing plate for offset printing and printing method for checking printing pressure - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a planographic printing plate for offset printing, and an offset printing method using the printing plate, and more particularly to offset printing capable of confirming a printing pressure for ink transfer between a planographic printing plate and a blanket. The present invention relates to a planographic printing plate and an offset printing method.
[0002]
[Prior art]
[0003]
[Patent Document 1]
Japanese Patent No. 3153033 [Patent Document 2]
JP 2001-138487 A [Non-Patent Document 1]
http // www.art-g.co.jp / art / techniq / lab / la.html
[0004]
Conventionally, there is known an offset printing method in which an ink held on an intaglio or plano-intaglio printing plate on which a desired pattern is formed is received on the surface of a blanket roll and further transferred from the blanket roll surface to a substrate. . The offset printing method has the advantages that the fine pattern formation accuracy is higher than that of the conventional screen printing method and the amount of ink used is smaller than that of the photolithography method. (See Patent Document 1).
[0005]
[Problems to be solved by the invention]
When forming a fine pattern, for example, an electrode pattern on the back plate of a plasma display panel, by mounting a silicone blanket on the surface of the blanket roll and using an intaglio printing plate, a planographic intaglio plate filled with conductive ink It is extremely important to determine the optimum value of the printing pressure between the printing plate and the blanket for receiving the ink when printing a fine pattern with high accuracy.
[0006]
When the printing pressure between the plano-intaglio printing plate and the blanket is excessively set, the ink reception to the blanket is unstable, and defects such as pinhole defects and alignment mark defects occur in the printed matter. When the printing pressure is too low, defects such as waviness occur in the line printed on the substrate. Conventionally, the printing pressure was calculated based on the thickness of the blanket mounted on the blanket roll or the thickness of the printing plate on the plano-intaglio plate . However, setting the printing pressure based on the calculated value eliminates the error due to the thickness. However, when printing was actually performed, the printing pressure between the plano-concave printing plate and the blanket was excessive or insufficient, and it was difficult to eliminate the defects.
[0007]
On the other hand, conventional commercial printing has a method of observing the density with a solid number of steps, or a method of printing a control strip (color mono-sashi) on all sheets and reading this to keep the color change within an allowable range (patent) Document 2, Non-Patent Document 1), this method is not for confirming the printing pressure.
[0008]
Accordingly, an object of the present invention is to provide a plano-concave printing plate and an offset printing method capable of easily confirming an optimum state of the printing pressure between the plano-intaglio printing plate and the blanket in offset printing. To do.
[0009]
[Means for Solving the Problems]
Flat intaglio printing plate of the present invention to solve the problems described above, in the flat intaglio printing plate for use in offset printing using a blanket roll equipped with a silicone blanket, display area printing pattern is formed Is a planographic intaglio printing plate for offset printing, characterized in that one or a plurality of printing pressure confirmation marks having progressively different area ratios are provided at a plurality of locations outside of the printing plate .
[0010]
In the planographic intaglio printing plate of the present invention, "one printing pressure confirmation mark having a gradually different area ratio" means that the area gradually changes in the length direction of one printing pressure confirmation mark. means. In addition, “a plurality of printing pressure confirmation marks with gradually different area ratios” means that a plurality of printing pressure confirmation marks forming one group have a gradually changing area. Since the planographic intaglio printing plate is usually rectangular, it is necessary to provide one or a plurality of printing pressure confirmation marks that form a group at each of the four corners of the printing plate. Desirable to check pressure. If the printing pressure confirmation mark provided on the planographic printing plate is not within the width of the blanket, the printing pressure confirmation mark on the printing plate cannot be transferred to the blanket.
[0011]
Further, the offset printing method of the present invention is the method for performing offset printing using the planographic printing plate of the present invention, wherein the printing pressure confirmation mark transferred from the printing plate to the silicone blanket surface or the blanket from by observing the printing pressure confirmation mark printed on the printing material, so as to determine the degree of printing pressure when the ink is transferred to the blanket from the flat intaglio printing plate, an appropriate printing pressure It is characterized by adjusting.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the present invention will now be exemplified, but the present invention is not limited thereto. FIG. 1 is a top view showing an example of a plano-concave printing plate provided with a printing pressure confirmation mark according to the present invention. The planographic intaglio printing plate 1 in FIG. 1 is an example in which the printing pressure confirmation mark 2 is a circle. In FIG. 1, reference numeral 3 denotes a display area in which a fine print pattern is formed. A plurality of printing pressure confirmation marks 2 having progressively different area ratios are provided around the four corners outside the display area 3 in the printing plate 1. The circle preferably has a minimum diameter of 10 μm and a maximum diameter of 50 mm.
[0013]
In order to adjust the printing pressure for transferring ink between the printing plate 1 and the blanket, a printing pressure adjusting mechanism 4 capable of adjusting the vertical position of the printing plate 1 is provided on the base of the offset printing machine. In the printing pressure adjusting mechanism 4, for example, printing pressure adjusting bolts or the like can be arranged at the four corners of the printing plate or at the four corners of the printing plate 24 (FIG. 5). The printing pressure is adjusted by raising and lowering the printing plate 1 or the printing plate 24 (FIG. 5). It is good also as a member which can adjust the up-and-down position of the printing plate 1 or the printing plate board 24 (FIG. 5) integrally.
[0014]
The printing pressure confirmation mark 2 shown in FIG. 1 has a plurality of circles with progressively different area ratios, but in addition to the circle, as shown in FIG. 2, a square (FIG. 2 (a)) and a rectangle (FIG. 2 (b)). ), A donut shape (FIG. 2C), a cross shape (FIG. 2D), a deformed cross shape (FIG. 2E), etc. One pattern shape with gradually different area ratios may be used, and Fig. 3 shows an example of the pattern shape in the case of one printing pressure confirmation mark 2. Fig. 3 (a) shows the printing pressure confirmation mark 2. Is a right triangle, and FIG. 3B is an isosceles triangle.
[0015]
Next, the entire process of offset printing will be described.
[0016]
FIG. 4 is a side view showing an example of an offset printing machine used in the present invention. FIG. 5 is a top view of the offset printing press shown in FIG. 4 and 5, the offset printing machine 21 includes a printing platen 24 on which a planographic intaglio printing plate 32 is mounted and a printing platen 23 on which a base material 31 as a substrate is placed at a predetermined interval. A base 22 on which two guide rails 25, 25 are laid in parallel, and a print head 26 that can freely move on the guide rails 25, 25 by a moving mechanism (not shown) are provided. Reference numeral 33 denotes a display area where a printing pattern is formed on the printing plate 32, and reference numeral 34 denotes a printing area where a target pattern is printed on the substrate 31.
[0017]
The print head 26 is provided with an up and down blanket roll 27 and a first inking roll group 28. The first inking roll group 28 includes a kneading roller that swings in the direction of the rotation axis of the roll, and an inking roll that applies ink to the printing plate. The base 22 is provided with a second inking roll group 29 and an ink blade 30 for storing ink. The second inking roll group 29 is composed of an ink discharge roll that ejects ink from the ink blade 30 and a kneading roller that swings in the rotation axis direction of the roll.
[0018]
In the offset printing machine 21, a substrate 31 that is a printed pattern forming body is placed on a printing surface plate 23, and a printing plate 32 is mounted on the printing plate 24. The print head 26 first moves on the guide rails 25, 25 onto the second inking roll group 29. Here, the ink kneaded and uniformed by the second inking roll group 29 is transferred to the first inking roll group 28 of the print head 26. Next, the printing head 26 moves on the guide rails 25, 25 toward the printing platen 24, and applies the conductive ink to the printing plate 32 by the inking roll of the first inking roll group 28. Thereafter, the print head 26 returns to the second inking roll group 29 side on the guide rails 25, 25, and the conductive ink kneaded and uniformed by the second inking roll group 29 again becomes the print head. Transferred to 26 first inking roll groups 28. During this time, the blanket roll 27 is raised to a position where it does not contact the printing plate 32. This ink application operation may be performed a plurality of times.
[0019]
Next, the print head 26 moves toward the printing surface plate 23 with the blanket roll 27 lowered to the printing position. When the print head 26 passes through the printing plate 24, the conductor ink on the image line portion of the printing plate 32 is transferred to the blanket roll 27, and at the same time, by the inking roll of the first inking roll group 28. Ink is newly applied to the printing plate 32. The print head 26 further moves toward the printing surface plate 23, and ink is printed from the blanket roll 27 onto the base material 31 placed on the printing surface plate 23. Thereafter, the print head 26 returns to the second inking roll group 29 side.
[0020]
In order to determine the degree of printing pressure when ink is transferred from the printing plate 32 to the blanket, the printing pressure confirmation mark transferred to the blanket surface of the blanket roll 27 or printed outside the printing area of the substrate 31 is printed. Observe the printing pressure confirmation mark. A printing defect in the mark for confirming the printing pressure is likely to occur in a portion corresponding to the latter half when ink is transferred from the printing plate to the blanket. Also, a mark with a larger area ratio is more likely to cause a printing defect. The printing plate 1 (or the printing plate 1 (or the printing plate 1 or the correlation is determined in advance) by adjusting the printing pressure adjustment mechanism 4 so that the printing pressure is best based on this correlation. 32), the printing pressure is adjusted by adjusting the vertical position, or the printing pressure is adjusted by adjusting the lower limit position of the lowering of the blanket roll 27.
[0021]
【Example】
In the offset printing press shown in FIGS. 4 and 5, the printing plate adopting the square shown in FIG. 2 (a) is used as the printing pressure confirmation marks formed at the four corners outside the display area of the plano-intaglio printing plate . It was. The square size of the mark for confirming the printing pressure was set to four types with one side of 0.5 mm, 1 mm, 1.5 mm, and 2.0 mm.
[0022]
In this offset printing machine, an ink having a viscosity of 7000 p (10 s-1) is used, and the ink filled in the concave portion of the planographic intaglio printing plate is transferred to a blanket roll having a silicone rubber blanket as the outermost surface. The ink was transferred in seconds, and ink was received in the blanket. When the printing pressure confirmation marks provided at the four corners of the plano-concave printing plate were printed on the substrate, it was confirmed that a square larger than 1 mm side was not printed accurately. Next, the printing pressure adjustment bolt is adjusted until it is printed until a square of 1 mm side of the printing pressure confirmation mark printed at the four corners of the substrate is printed, and then normal printing is performed. Started. Here, a plano-concave plate having a plate depth of 4 μm was used as a printing plate for offset printing .
[0023]
【The invention's effect】
According to the present invention, by visually confirming the degree of printing pressure when ink is transferred from a printing plate to a blanket, it is possible to prevent the occurrence of defects such as pinhole defects and poor alignment in printed matter. .
[Brief description of the drawings]
FIG. 1 is a top view showing an example of a printing plate provided with a printing pressure confirmation mark according to the present invention.
FIG. 2 shows an example of a printing pressure confirmation mark having a shape other than a circle.
FIG. 3 shows an example of a pattern shape when there is one printing pressure confirmation mark.
FIG. 4 is a side view showing an example of an offset printing machine used in the present invention.
FIG. 5 is a top view of the offset printing machine shown in FIG. 4;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Printing plate 2 Printing pressure confirmation mark 3 Display area 4 Printing pressure adjustment mechanism 21 Offset printing machine 22 Base 23 Printing surface plate 24 Printing plate plate 25 Guide rail 26 Print head 27 Blanket roll 28 First inking roll group 29 Second inking roll group 30 Ink blade 31 Base material 32 Printing plate 33 Display area 34 Printing area

Claims (6)

In a planographic intaglio printing plate used for offset printing using a blanket roll equipped with a silicone blanket, one or a plurality of progressively different area ratios are provided at a plurality of locations outside a display area where a printing pattern is formed. A planographic printing plate for offset printing, which is provided with a mark for confirming printing pressure. 2. The planographic printing plate for offset printing according to claim 1, wherein the planographic printing plate for offset printing is used for forming an electrode pattern on a back plate of a plasma display panel. 3. The planographic printing plate for offset printing according to claim 1 or 2, wherein the printing pressure confirmation marks are respectively provided at four corners of the planographic printing plate . The planographic intaglio printing plate for offset printing according to any one of claims 1 to 3, wherein the printing pressure confirmation mark is within a range of a width of a blanket used for offset printing. In the method of performing offset printing using the plano-intaglio printing plate according to any one of claims 1 to 4, a printing pressure confirmation mark transferred from the printing plate to a silicone blanket surface, or from the blanket By observing the mark for confirming the printing pressure printed on the substrate, the degree of printing pressure when the ink is transferred from the planographic intaglio printing plate to the blanket is determined and adjusted to obtain an appropriate printing pressure. An offset printing method characterized by: The offset printing method according to claim 5, wherein the offset printing method is applied to printing of an electrode pattern on a plasma display panel back plate.

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