JP2009072994A - Screen printing plate and electric conduction pattern formed thereby - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing plate that suppresses leak of an electric conduction pattern caused by blurring in screen printing. <P>SOLUTION: The screen printing plate is provided with an opening part 1 from which a printing material for forming an intended printing pattern is discharged onto a printing object. This opening part 1 is belt-shaped, wherein the corner of the bent part 4 where the opening part bends with an angle from a parallel direction to a direction vertical to the printing direction is rounded. Also, the screen printing plate is characterized in that the width of the belt-like opening part 1 arranged vertically to the printing direction is narrower than the target printing pattern. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a screen printing plate provided with an opening for discharging a printing material for forming a target printing pattern on a substrate in screen printing.

  In screen printing, a printing material is placed on a screen printing plate composed of an opening and a non-opening, and the printing material is ejected from the opening of the screen printing plate by translating the squeegee on the screen printing plate. In this method, printing is performed by transferring a printing material to a printing surface arranged under a printing plate.

  Printing plates used for screen printing include those in which a mesh-like screen serving as an opening is patterned with an emulsion and a metal mask in which openings are formed by etching a thin metal plate. Conventionally, when a pattern is printed using these screen plates, the area of the target print pattern region is expanded due to bleeding of the printing material from the opening.

  For example, when printing in the direction of arrow 6 using a screen printing plate having openings 5 as shown in FIG. 2 in the same pattern as the print pattern in order to print a belt-like print pattern, the printed pattern after printing is blurred. Arise. FIG. 3 shows a print pattern after printing. The positions of the original openings are dotted lines 13, 14, 15 and 16. In this way, the printed patterns 10, 11, and 12 that are printed with respect to the original opening part generally bleed, but the straight line part 7 in FIG. 2 positioned in the direction perpendicular to the squeegee movement direction is particularly printed The discharge amount of the material is increased, and the material is more likely to bleed as illustrated in part a of FIG.

  FIG. 4A is an enlarged view of part a of FIG. 3, but there are also portions where adjacent print patterns 10 and 11 stick together as shown in FIG. 4A. Further, the printing pattern of the bent portion 9 that bends in a direction perpendicular to the direction parallel to the arrow 6 that is the squeegee moving direction, that is, the printing direction shown in FIG. In FIG. 4B, the print patterns 11 and 12 are stuck together as shown in FIG. 4B.

  Table 1 shows the results of actual printing using a stainless steel mesh with a mesh number of 250 and an emulsion film pressure of 20 μm for the purpose of forming a strip-shaped printing pattern having a width of 100 μm. The design value of the opening of the screen printing plate was set to a width of 100 μm as with the target value.

  The maximum value, minimum value, and median value of the print width were measured for both the print pattern in the parallel direction (parallel straight line) and the print pattern in the vertical direction (vertical straight line) with respect to the squeegee movement direction. As shown in Table 1, it can be seen that the print width is larger than the target value, and the print pattern in the vertical direction is more blurred.

  The causes of this bleeding include a high printing pressure during printing, the intersection of screen printing plate meshes, and the low viscosity of the printing material.

  As a measure for preventing this bleeding, there is a method of providing a narrow partition with a constant height along the periphery of the opening on the side of the screen printing plate that comes into contact with the substrate (Patent Document 1), or a target printing pattern in the opening. A method of printing with a screen printing plate having a reduced uneven pattern shape (Patent Document 2) is disclosed.

Japanese Patent Laid-Open No. 5-270161 (page 3, FIG. 1) JP 2006-347077 (6th page, FIG. 1)

  Although the prior art method can prevent bleeding, the method for producing a screen printing plate is complicated and the production cost is increased. In actual printing, blurring may occur easily depending on the moving direction of the squeegee relative to the print pattern and the print pattern.

  An object of the present invention is to provide a screen printing plate that is easy, low-cost and excellent in printability by changing the printing pattern shape itself, and suppresses bleeding during printing.

  In order to achieve the above object, in the present invention, a screen printing plate provided with an opening for discharging a printing material for forming a target printing pattern on a substrate, the opening is in a strip shape, The corner of the bent portion where the opening bends at an angle in a direction perpendicular to a direction parallel to the printing direction has a rounded shape.

  In addition, the width of the band-shaped opening arranged in a direction perpendicular to the printing direction is narrower than the target printing pattern. Moreover, this invention is the conductive pattern formed with this screen printing plate.

  According to the present invention, by producing a screen printing plate having an opening in consideration of the squeegee moving direction, screen printing excellent in printability at low cost and without causing bleeding in the printing pattern regardless of the printing direction. A plate can be provided, and a more detailed drawing pattern or the like can be printed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to this.

  As shown in FIG. 1, the straight line portion 3 in which the print pattern is provided in the direction parallel to the arrow 2 which is the squeegee movement direction, that is, the print direction, in the opening 1 of the screen printing plate is the target print pattern. The bent portion 4 that is bent at an angle from a parallel direction to a perpendicular direction has a rounded shape.

  As the screen printing plate, a printing plate having a mesh number of 250 using a stainless mesh and an emulsion film pressure of 20 μm was prepared. The line width of the target belt-shaped printed pattern is set to 100 μm, the opening is designed based on the conventional value, and the band-shaped opening arranged in the vertical direction is made smaller than the target 100 μm to actually Was 75 μm.

  When printing was performed using such a screen printing plate, the results shown in Table 2 were obtained. With respect to both the print pattern in the parallel direction (parallel straight line) and the print pattern in the vertical direction (vertical straight line) with respect to the squeegee moving direction, the respective print widths were measured. As shown in Table 2, the line width of the print pattern in the vertical direction was almost 100 μm, and the target print pattern could be formed.

Next, using this screen printing plate, a conductive paste was printed on a glass substrate with ITO to obtain a conductive pattern. The conductive paste used has a viscosity of 25 Pa · s. Prior to printing, the mixture was sufficiently stirred with a stirrer. As printing conditions, a squeegee with a hardness of 80 ° was set at an angle of 70 ° with respect to the printing surface, and the squeegee speed was 200 mm / s.

  After printing, firing was performed in a firing furnace, and the printed state after printing and the printed width of the conductive paste were observed with an optical microscope. The printing width was almost the same as in Table 2. Moreover, the printing state is shown in FIG.

  As shown in FIG. 5, the printed state of the conductive paste is the same as that of the conventional FIG. 3, but the bleeding of the conductive pattern in the direction parallel to the squeegee movement direction is the same, but the strips are arranged in the vertical direction. Since the design value of the opening is thin, the adjacent conductive patterns 17 and 18 do not stick together. In addition, even if the bent portion 19 where the straight lines parallel to the vertical line have the same bleeding, the patterns do not stick to each other because the corner 19 is rounded. Also, the line width of the conductive pattern after printing is closer to the target printing width than the conventional printing pattern.

It is the top view which showed the opening part of the screen printing plate of this invention. It is the top view which showed the opening part of the conventional screen printing plate. It is the top view which showed the conventional printing pattern. It is the enlarged view which showed the conventional printing pattern. It is a top view of the conductive pattern printed with the screen printing plate in this invention.

Explanation of symbols

1, 5 Opening 3, 7 Linear part 4, 9, 19 Bent part 10, 11, 12 Print pattern 17, 18 Conductive pattern

Claims (3)

A screen printing plate provided with an opening for discharging a printing material for forming a target printing pattern on a substrate,
The screen printing plate characterized in that the opening has a belt-like shape, and the corner of the bent portion where the opening bends at an angle in a direction perpendicular to a direction parallel to the printing direction has a rounded shape. .   2. The screen printing plate according to claim 1, wherein a width of the band-shaped opening arranged in a direction perpendicular to a printing direction is narrower than the target printing pattern.   A conductive pattern formed of the screen printing plate according to claim 1.

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