JP3890438B2 - Printing plate and manufacturing method thereof - Google Patents

Description

  The present invention relates to a printing plate capable of forming a pattern with high accuracy and a method for producing the same, and in particular, a high-viscosity paste such as solder paste printing, conductive paste printing, conductive bump printing, and underfill dam printing in the field of electronic components. The present invention relates to a printing plate used for printing and a manufacturing method thereof.

  FIG. 6 is a manufacturing process diagram of a conventional printing plate. A resist film 10 is laminated on the surface of the metal sheet 9, and this resist film 10 is exposed and developed with UV light (ultraviolet light) or the like, thereby forming a resist pattern 10a having the same opening pattern as the printing pattern. Then, the metal sheet 9 is etched using the resist film 10 as a mask (FIG. 6A), and then the resist film 10 is removed to form a printing plate 12 in which through holes 11 corresponding to the printing pattern are formed. Is done.

  However, when etching is performed by wet etching using an etchant, the etching holes formed in the metal sheet 1 are not formed perpendicular to the thickness direction of the metal sheet, but as shown in FIG. , It is formed while spreading radially. Then, side etching occurs, and the opening of the etching hole becomes large. In addition, variations occur due to differences in etching conditions (spray pressure variations, temperature, etchant flow, etc.). As described above, it is difficult to control the size of the etching hole because advanced condition management and expensive equipment are required, and a desired print pattern cannot be obtained.

  Further, if a printed pattern is formed on a metal sheet by etching using a laser, the accuracy of the printed pattern can be improved, but only one hole can be formed per shot, and mass production cannot be performed. In addition, there is an electroforming plate by plating instead of etching, but it is expensive.

  In view of the above problems, an object of the present invention is to provide a printing plate that can form a highly accurate printing pattern and can be mass-produced, and a method for manufacturing the same.

  In order to achieve the above object, the present invention is characterized in that the primary resist layer is used as it is as a part of the printing plate. That is, the present invention is a printing plate characterized in that a primary resist layer having a resist pattern, which is laminated on the printing surface side of a metal plate, is used as a printing pattern forming layer at the time of printing. When the metal plate is etched, the etching proceeds radially from the opening of the resist pattern, so that the opening of the etching hole becomes larger than the opening of the resist pattern, but the present invention leaves the primary resist layer as it is. By using it as a print pattern layer, a high-precision print pattern can be formed.

  That is, since the opening peripheral edge portion of the resist pattern of the primary resist layer regulates the width of the printing material, the size of the hole in the resist pattern determines the printing pattern. Since the resist pattern of the primary resist layer has an opening pattern corresponding to the target print pattern, a highly accurate print pattern can be formed as desired. Thus, this invention uses a primary resist layer together as a resist layer and a printing pattern formation layer.

  The printing plate of the present invention can be applied to various printing plates such as solder paste printing, conductive paste printing, conductive bump printing, underfill dam printing, ink printing, etc., and combination type screen printing printing. It can also be applied to a version. In addition, the through hole is not a narrow hole penetrating in a circular shape or a polygonal shape, but a space that penetrates from the printing surface side of the printing plate to the printing material supply surface side, It refers to a hole that can be used to form any printed pattern such as a curve.

  The printing material means a pattern forming material, and examples thereof include solder paste (cream solder), PDP partition molding composition, printing ink, and the like, which are particularly suitable for high viscosity printing materials. is there.

  Etching to the metal plate is preferable if wet etching (chemical etching) using an etching solution is used because mass production can be performed at once.

  Etching may be performed from only one of the printing surface of the metal plate and the printing material supply surface on the opposite side, but from both sides, etching holes made from the printing surface side of the metal plate, It is preferable to form a through hole in the metal plate in communication with an etching hole formed from the printing material supply side. If etching is performed from only one side, the etching holes will expand radially, so there is a risk of merging with adjacent through holes. It does not need to be large. Therefore, it is possible to correspond to a dense print pattern.

  When etching is performed from both sides, etching may be performed from both sides at the same time, but the etching holes made from the printing surface side are made shallower than the etching holes made from the printing material supply side. Is preferred. Making the etching hole shallow means reducing the etching action, and the depth of the etching hole may be adjusted by changing the time of exposure to the etching solution, the concentration of the etching solution, or the like. If the etching hole on the printing surface side is shallow, the hole does not expand in the lateral direction, so that the size of the etching hole on the printing surface side can be reduced. Therefore, it is not necessary to put a burden on the primary resist layer that regulates the opening of the etching hole.

  The thickness of the metal plate is preferably 70 μm to 200 μm. As the thickness of the metal plate increases, the volume of the through hole formed in the metal plate increases. Further, since most of the printing material filled in the through holes is transferred to the printing medium side, the volume of the printing pattern transferred to the printing medium increases as the thickness of the metal plate increases. Therefore, if the thickness of the metal plate is set so as to have the above thickness, a print pattern having a sufficient volume can be obtained particularly during solder paste printing. That is, it becomes possible to thicken the printing material.

  Moreover, it is preferable that the thickness of a primary resist layer shall be 25 micrometers-100 micrometers. If the thickness is less than 25 μm, the printing material cannot be sufficiently regulated, and the primary resist layer is bent, so that a highly accurate resist pattern cannot be formed. Further, a thickness of 100 μm is sufficient, and no further thickness is necessary. If it is in the range of 25 μm to 100 μm, the printing material can be sufficiently regulated to form a highly accurate printing pattern.

  According to the present invention, the primary resist layer laminated on the printing surface side of the metal plate is used as a printing pattern forming layer at the time of printing, so that the primary resist layer regulates the width when the printing material is discharged to the printing medium. Therefore, a highly accurate printing pattern can be formed. Moreover, since it can etch using the wet etching by an etching liquid, mass production is possible.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1A is a plan view of the printing plate of the present embodiment, FIG. 1B is a cross-sectional view thereof, FIG. 2 is a cross-sectional view illustrating the manufacturing process of the printing plate main body of the present embodiment, and FIG. FIG. 3B is a sectional view thereof, FIG. 4A is a plan view of a printing plate of another embodiment, FIG. 4B is a sectional view thereof, and FIG. FIG. 3 is a diagram showing an outline of a printing process of a printing plate of the present embodiment. 1B, FIG. 2, FIG. 3B, FIG. 4B, and FIG. 5, the lower surface is the “printing surface side” and the upper surface is the “printing material supply surface side”.

  As shown in FIG. 1 and FIG. 2A, the present printing plate is made of a printing plate main body 3 in which a primary resist layer 2 is laminated on the printing surface side of a metal plate 1 and a mesh stretched on a frame 4. This is a combination type screen printing plate comprising the support screen 5. The printing plate body 3 is stretched in an opening formed in the center of the support screen 5. In the present embodiment, the combination type screen printing plate is exemplified. However, as shown in FIG. 3, the printing plate may be composed of the printing plate body 3 and the frame body 4 on which the printing plate body 3 is stretched. Alternatively, as shown in FIG. 4, the printing plate may be configured by only the printing plate main body 3. When the printing plate is constituted only by the printing plate main body 3, it may be used by being stretched on a frame (not shown) provided in a printing machine (not shown).

  Examples of the metal plate 1 include, but are not limited to, iron, copper, aluminum, and stainless steel. Moreover, although the thickness shall be 70 micrometers-200 micrometers, it is not limited to this. The metal plate 1 is formed with through holes 6 that can be filled with a printing material in the thickness direction by etching. If a release agent is applied to the inner surface of the through hole 6 or a smooth surface process such as a coating process with a lubricating material such as molybdenum is applied, the printing plate is separated from the printing medium a. In this case, it is preferable because the printing material can hardly adhere to the printing plate.

  The primary resist layer 2 uses a polymer film, but is not limited to this as long as it is a material that is not etched by the etchant and is a photosensitive material. Moreover, the thickness shall be 25 micrometers-100 micrometers. A resist pattern corresponding to the target print pattern is formed on the primary resist layer 2 by exposure and development. Note that the resist pattern may be formed by laser processing. The primary resist layer 2 having this resist pattern is left without being removed after the etching of the metal plate 1 and functions as a printed pattern forming layer at the time of printing.

  Next, a method for producing a printing plate will be described. First, a primary resist layer 2 is formed by laminating a resist film made of a photosensitive material on the printing surface side of the metal plate 1 (FIG. 2A), and the primary resist layer 2 is exposed and developed to obtain a desired value. A resist pattern of the shape is formed (FIG. 2B).

  Then, a secondary resist layer 7 is formed by laminating a resist film on the printing material supply surface side of the metal plate 1, and the printing surface side of the metal plate 1 is etched (FIG. 2C). The non-existing portion 2 a of the primary resist layer 2 is etched to form a hole 6 a from the printing surface side of the metal plate 1. Etching is performed by wet etching, and a hydrogen fluoride-based liquid or the like is used as the etching liquid. At this time, since the resist pattern is not formed in the secondary resist layer 7, the printing material supply surface side of the metal plate 1 is not etched. The secondary resist layer 7 uses a polymer film, but is not limited to this as long as it is a material that is not etched by the etchant and is a photosensitive material.

  Next, in order to cover the surface of the primary resist layer 2, a tertiary film layer 8 is laminated on the surface, and a resist pattern 7a having the same pattern as the primary resist layer 2 is formed on the secondary resist layer 7 (FIG. 2D). )). Then, the metal plate 1 is etched from the printing material supply surface side. At this time, since the resist pattern is not formed on the tertiary film layer 8, the etching from the printing surface side of the metal plate 1 does not proceed. Then, etching is performed from the non-existing portion 7a of the secondary resist layer 7 to form a hole 6b in the metal plate 1, which communicates with the etching hole 6a formed from the printed surface side, and passes through the metal plate 1 6 is formed. In addition, although the polymer film is used for the tertiary resist layer 8, if it is a raw material which is not etched with an etching liquid, it will not be limited to this.

  In the etching step, the etching hole 6a from the printing surface side is made from the printing material supply side by making the etching time from the printing surface side shorter than the etching time from the printing material supply side. It is made shallower than the etching hole 6b. The depth of the etching hole may be adjusted by making the concentration of the etching solution at the time of etching from the printing surface side smaller than the concentration of the etching solution at the time of etching from the printing material supply side. Good.

  Then, by removing the secondary resist film and the tertiary film layer 8 and leaving the primary resist layer 2, the printing plate main body 3 is completed (FIG. 2E). If this printing plate body 3 is stretched in the opening formed in the center of the mesh support screen 5 stretched on the frame 4, a combination type screen printing plate is completed.

  A printing process using this printing plate will be described with reference to FIG. First, the printing material c is placed on the printing material supply surface of the metal plate 1, and the through-hole 6 is filled by moving the printing plate body 3 while bending the printing plate body 3 by pressing the printing plate body 3 with a squeegee b or the like. The printed material c is extruded from the opening of the through hole 6 to the printing surface side. Although the opening of the through hole 6 on the printing surface side of the metal plate 1 is larger than the desired size due to the occurrence of side etching, the primary having an opening pattern corresponding to the desired printing pattern on the printing surface side. Since the resist layer 2 is laminated, the width W of the print pattern d can be regulated by the primary resist layer 2.

  That is, the opening 2a of the primary resist layer 2 exhibits the function of a squeeze port, and a desired print pattern d can be formed on the printing medium a. Therefore, the primary resist layer 2 functions as a print pattern forming layer at the time of printing, and can form a highly accurate print pattern d. Thus, the primary resist layer 2 functions as an etching resist layer during etching and functions as a printed pattern forming layer during printing. Furthermore, since the primary resist layer 2 has flexibility, it can follow the unevenness of the surface of the substrate a to be printed, so that the accuracy of the printing pattern d is further improved.

  Further, since the etching process is performed by wet etching, a large number of through holes 6 can be formed at one time, and mass production is also possible.

  Furthermore, since the etching hole 6a formed from the printing surface side is shallower than the etching hole 6b formed from the printing material supply side, it is possible to form a printing pattern d with higher accuracy. That is, if the etching hole 6a on the printing surface side is made shallow, the size of the etching opening from the printing surface side does not need to be increased, so the area of the portion 2b of the primary resist layer 2 that regulates the opening is also large. I don't have to. Accordingly, the burden on the primary resist layer 2 is reduced, and a highly accurate printed pattern can be formed.

  Further, most of the printing material c filled in the through hole 6 of the printing plate body 3 and the non-existing portion 2a of the primary resist layer 2 is extruded onto the printing medium a. Therefore, the sum of the volumes of the printing material c filled in the through holes 6 of the printing plate body 3 and the non-existing portions 2a of the primary resist layer 2 is substantially equal to the volume of the printing pattern d formed on the printing medium a. It will be the same. Therefore, the volume of the printing pattern d may be adjusted by adjusting the volume of the through hole 6 of the printing plate body 3. The volume of the through hole 6 may be adjusted by adjusting the etching time.

(A) is a plan view of the printing plate of this embodiment, (b) is a cross-sectional view thereof Sectional drawing which shows the manufacturing process of the printing plate main body of this embodiment (A) is a plan view of a printing plate of another embodiment, (b) is a cross-sectional view thereof (A) is a plan view of a printing plate of another embodiment, (b) is a cross-sectional view thereof The figure which shows the outline of the printing process of the printing plate of this embodiment Sectional drawing which shows the manufacturing process of the conventional printing plate

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal plate 2 Primary resist layer 3 Printing plate main body 4 Frame body 5 Support body screen 6 Through-hole 7 Secondary resist layer 8 Tertiary film layer a Printed object b Squeegee c Printing material d Printing pattern

Claims (2)

A primary resist layer is laminated on the printing surface side of the metal plate, a secondary resist layer is laminated on the printing material supply surface side of the metal plate, etching is performed from both sides, etching holes from the printing surface side, and printing material A printing plate manufacturing method for forming a through hole for filling a printing material by communicating with an etching hole from the supply surface side, comprising: etching from the printing surface side; etching from the printing material supply surface side; Are formed separately so that the etching hole formed on the printing surface side is shallower than the etching hole formed on the printing material supply surface side, and the primary resist layer is left as a printed pattern forming layer. A method for producing a printing plate. After etching the metal plate from the printing surface side, a tertiary film layer is laminated on the surface side of the primary resist layer, and then the metal plate is etched from the printing material supply surface side, thereby etching from the printing surface side. The method for producing a printing plate according to claim 1, wherein etching from the printing material supply surface side is performed separately.

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