JP3516882B2 - Screen printing plate and its manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a screen printing plate using a metal screen. More specifically, when the cloth is stretched, the tension of the cloth tension is stabilized early and the thickness of the screen is made constant, and when the plate is made, the adhesiveness between the resist film and the screen is improved,
Improves dimensional accuracy, improves ink permeability during printing, increases paste transfer amount, eliminates waste of printing, improves position accuracy of printed matter, and makes printed film thickness uniform. The present invention also relates to a method for producing a screen printing plate that can improve printing durability.

[0002]

2. Description of the Related Art Conventionally, metal screen fabrics used for screen printing plates generally have a diameter of 13 to 160 μm.
Metallic woven screen obtained by weaving stainless steel wire etc. into plain weave, twill weave, etc., and opening many fine pores obtained by electroforming (electroforming) A metal plate-shaped screen is known.

[0003]

However, such metallic woven screens and metallic plate-shaped screens obtained by the electroforming method (electroforming) are not suitable for ordinary polyester woven screens. Since it is more expensive than the above screen, it was used for things that require high dimensional accuracy. However, such metallic woven screens and metallic plate screens have problems such as easy peeling from the photosensitive resin film, early stabilization of the tension of tension, and constant screen thickness. However, there was a problem in making the printed film thickness uniform. In addition, such a woven metal screen or a plate-shaped metal screen obtained by the electroforming method (electroforming) has a fine fiber diameter, but must be stretched with extremely strong tension on the mold. Therefore, if the fiber itself is cut, there will be problems such as deterioration of printing accuracy and distortion of the image, so be careful not to scratch the surface of the fiber in order to stretch the screen on the formwork. It was stretched out. However, the metal screen woven from such wire or the like has a problem in that it has poor adhesiveness to the resin photosensitive film and is peeled off during printing to limit the number of printed sheets.

[0004]

The present inventor has conducted extensive studies in view of the above problems, and as a result, the metal screen is
If you lose the smoothness of the surface and increase the surface area,
The present invention has been completed based on the finding that the adhesiveness to the image layer made of a photosensitive resin can be increased.

That is, in the method for producing a screen printing plate of the present invention, a photosensitive emulsion is applied to the surface of a metal screen stretched on a mold and dried to form a photosensitive resin layer, and then a mask is used. In the production of a screen printing plate in which a latent image is formed by exposure through light and an image layer is formed by development, the metal screen sprays 100 to 2,000 mesh particles on its surface. And / or buffing, the surface of the metal screen is ground.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION [I] Screen printing plate (1) Constituent material (A) Form frame The form frame used in the method for producing the screen printing plate of the present invention is generally from the viewpoint of strength and corrosion resistance. Aluminum pipe joint type and die cast type,
Alternatively, a stainless steel mold can be used. Among these molds, it is preferable to use an aluminum mold.

(B) Metal Screen (a) Type As the metal screen used in the present invention,
Generally, a woven fabric of 40 to 590 mesh generally obtained by weaving a metal wire such as a metal wire made of stainless steel, nickel, brass, adjacent bronze, copper or the like having a diameter of 13 to 160 μm into a woven fabric such as a plain weave or a twill weave. Metal screen, or a foil-shaped or thin plate-shaped nickel sheet having a diameter of preferably 37 to 160 μm and a thickness of 17 to 44 μm, which is formed by electroforming (electroforming) And other metal screens. Among these metal screens, it is preferable to use a screen of preferably 40 to 590 mesh obtained by weaving stainless wire having a diameter of preferably 13 to 160 μm.

(B) Upholstery The metal screen is used by upholstering the mold by a method such as a direct tension method or a combination method. The metal screen is a combination type screen in which the peripheral portion of the metal screen is attached to a woven fabric made of metal or a thermoplastic resin fiber, which is economical in terms of dimensional accuracy. Also, a suitable screen can be used.

(C) Recessed portion The surface of the metal screen has a roughness of 0.05-2.
It is important that recesses having a size of 0 μm, preferably 0.1 to 10 μm are formed. Since the recesses are fine, a pattern such as a satin pattern or a hairline pattern is generally formed as a whole. It usually looks like this. Measurement of Roughness The roughness of the concave portion is measured by a commercially available surface roughness measuring instrument (a surface shape measuring microscope VF-750 manufactured by Keyence Corporation).
0) allows the roughness of the recess to be measured. If the roughness is less than 0.05 μm, the adhesive strength between the screen and the photosensitive emulsion is not improved, and if it exceeds 20 μm, the strength of the screen is lowered. The total area of the recesses having the roughness of 0.05 to 20 μm occupies 10% or more, preferably 40% or more, and particularly preferably 60 to 100% of the surface excluding the intersections of the metal screens. Is desirable. If the area of the recess is too small, the adhesiveness of the photosensitive resin layer tends to decrease.

(C) Image Layer The image layer is a layer made of a photosensitive resin, on which various images are formed according to the purpose of use. Photosensitivity
Resin As the photosensitive resin, a known photosensitive resin can be used. Specifically, for example, Japanese Patent Publication No. 4-1
JP-A-9543, a partially saponified vinyl acetate polymer containing a water-soluble photocrosslinking agent and having a saponification degree of 70 to 99 mol%, and a saponification containing a photocrosslinkable group having photocrosslinkability by itself. In a dispersion medium composed of a water-soluble polymer selected from partially saponified vinyl acetate polymers having a degree of 70 to 99 mol%,
Photosensitive resin composition obtained by dispersing a water-insoluble or sparingly soluble photoactive compound having one or more ethylenically unsaturated groups containing a dispersoid composed of hydrophobic polymer particles and a photopolymerization initiator. The thing etc. can be mentioned.

(2) Effect The screen printing plate obtained by the method for producing a screen printing plate of the present invention as described above has a rapid tensioning of the tensioning force and a constant screen thickness during tensioning.
Also, during plate making, the adhesiveness between the resist film and the screen can be improved and the dimensional accuracy can be improved. Further, during printing, the ink permeability can be improved, increasing the paste transfer amount and eliminating waste printing. The advantages are that the positional accuracy of printed matter can be improved, the printed film thickness can be made uniform, and printing durability can be improved. As an example of a suitable method for producing the screen printing plate, the production method will be described below.

[II] Manufacture of screen printing plate (1) Manufacture of metal screen stretched on mold (A) Form frame As a mold used in the method for manufacturing a screen printing plate of the present invention, strength and From the viewpoint of corrosion resistance, a pipe joining type or die casting type generally made of aluminum, or a stainless steel form can be mentioned. Among these molds, it is preferable to use an aluminum mold.

(B) Metal Screen As the metal screen stretched on the above-mentioned mold, a metal wire such as a metal wire of stainless steel, nickel, brass, adjacent bronze, copper or the like having a diameter of preferably 13 to 160 μm is plain-woven, Obtained by weaving into a woven fabric such as a twill, preferably 4
A woven metal screen having a mesh size of 0 to 590, or a foil formed by electroforming (electroforming) and having a diameter of preferably 37 to 160 μm, and generally a thickness of 17 to 44 μm. A metal screen such as a flat or thin plate made of nickel can be used. Among these metal screens, it is preferable to use a screen of preferably 40 to 590 mesh, which is obtained by weaving stainless wire having a diameter of preferably 13 to 160 μm.

(C) Tensioning The metal screen can be stretched on the above-mentioned mold by any method known in the art in which a conventional metal screen is stretched on the mold. Specifically, the cloth can be stretched by a method such as a direct method or a combination method. However, after a screen made of a woven fabric woven from thermoplastic resin fibers is stretched on the mold, the metal screen is attached to the metal or thermoplastic resin screen with an adhesive, and the overlapped metal screen is used. Or, by partially cutting off the thermoplastic resin screen, a combination system screen in which the peripheral edge of the metal screen is a thermoplastic resin screen is also suitable in terms of dimensional accuracy and economically. can do.

(2) Grinding of metal screen surface In order to form a recess on the surface of the metal screen, generally, the surface of the metal screen is ground by sandblasting and / or buffing as shown below. By doing so, the recess can be formed. (A) Sandblasting In the sandblasting, the surface is ground by ejecting an abrasive together with a medium onto the surface of the metal screen and colliding the abrasive with the surface of the metal screen. Air or water is generally used as the medium used in the sandblast treatment, and among them, it is preferable to use air as the medium.

(A) Abrasive Material As the powdery or granular material (abrasive material) sprayed in the sandblasting treatment, there may be mentioned plastic, glass, carbon, carborundum, alumina, silica, silica-alumina and the like. Alumina is preferably used among these powders. The particle size of the abrasive is generally 20 to 4,000 mesh, preferably 10
A mesh of 0 to 2,000 mesh is used.

(B) Grinding condition Abrasive jetting pressure The abrasive jetting pressure is generally 0.05 in terms of air pressure.
~ 0.7 MPa , Preferably 0.1 to 0.5 MPa. The sandblast treatment is usually carried out at room temperature, but it may be carried out under heating. Time The sandblasting time is 200m in area.
In the case of m × 200 mm, it is usually performed for about 5 to 300 seconds, preferably about 20 to 150 seconds. In the grinding treatment by the sandblasting treatment, a large number of abrasive particles are blown with air or water together with a medium to grind them, so that it is difficult to specify the place to be blown and the treatment is difficult. Sometimes spraying is repeated. Therefore, the total area to be ground may exceed the total area of the surface of the metal screen excluding the intersections.

(C) Grinding device In the grinding process, a usual sandblasting device can be used. Specific examples include a sand blasting device “Pneumatic Blaster” manufactured by Fuji Seisakusho Co., Ltd. SG type gravity type and SC type fine powder abrasive type.

(D) Shape of Recesses It is important that an infinite number of recesses having a depth of 0.05 to 20 μm are formed on the surface of the metal screen by grinding in this manner. When viewed from the entire surface of the metal screen, it generally looks like a satin pattern is formed.

(B) Buffing Treatment As the above-mentioned buffing treatment, the surface of a metal screen is rubbed against a brush buff made of metal vegetated with steel wire or the like rotating at a high speed, or rotated at a high speed. The surface of the metal screen is ground by pressing the surface of the metal screen against a cloth buff coated with a buff abrasive that is a mixture of an abrasive such as calcined alumina with oil and fat, or by sandpaper and the like. Can form a recess. In order to industrially carry out the buffing treatment, a large number of linear roughnesses of 0.05 to 20 μm can be obtained by slowly passing between rotating metal brushes and cloth buffs.
It is possible to form a hairline-shaped pattern composed of concave portions. However, such a concave portion has a straight or curved hairline pattern different from the satin finish pattern by sandblasting, and can be clearly distinguished from the satin finish pattern.

(3) Formation of Photosensitive Resin Layer (A) Coating of Photosensitive Emulsion The photosensitive emulsion is applied to a metal screen having concave portions formed by applying sandblasting and / or buffing to the above mold. And prevent the photosensitive resin layer from peeling off from the metal screen because the photosensitive resin layer cures when the photosensitive emulsion enters the recesses formed on the metal screen when dried. You can
Examples of the photosensitive emulsion to be coated include the photosensitive resins used in the above image layer.

(B) Exposure The metal screen is placed on a mold, sandblasted and / or buffed, and then coated with a photosensitive emulsion.
PS for screen printing that is dried and has a photosensitive resin layer formed
Laminate a positive or negative film separately photoengraved on the plate,
A latent image is formed by irradiating light rays such as ultraviolet rays from the positive or negative film side to partially cure the photosensitive resin layer.

(4) Image Formation (A) Development / Drying The image layer can be formed by washing the photosensitive resin layer on which the latent image is formed with water or the like and developing it. When an ordinary water-soluble photosensitive resin such as polyvinyl alcohol is used, it can be developed with ordinary water.

(B) Image layer The cured photosensitive resin layer remaining after the uncured photosensitive resin layer has been washed away by the development described above enters the concave portion formed on the surface of the metallic screen and firmly adheres to the metallic screen. Since it is adhered to, the printing durability can be improved.

[0025]

EXAMPLES The present invention will be described in more detail with reference to the following examples and comparative examples. Example 1 and Comparative Example 1 (1) Gauze step 320 × 320 mm size aluminum die cast frame,
A woven stainless steel screen having a thickness of 64.0 μm and 325 mesh was stretched by a mechanical stretching machine to produce two plates in which the stainless steel screen was stretched on an aluminum frame.

(2) Sandblasting step One of the above two plates is sandblasted for 60 seconds on the printing surface side with a sandblasting machine SC type manufactured by Fuji Seisakusho using sandblasting material No. 800 (alumina). went. On the other hand, the other of the two plates was not subjected to the sandblast treatment. As a result, the surface of the sandblasted stainless steel screen was measured with a surface roughness measuring instrument (a surface shape measuring microscope VF-7500 manufactured by Keyence Co., Ltd.) to find that the roughness was about 3 μm. A large number of marks (ratio of concave portions: 60%) were confirmed, and a satin pattern was formed on the entire surface of the stainless screen (Example 1).

On the other hand, no recesses were confirmed and no satin finish was formed on the surface of the stainless steel screen which was not sandblasted (Comparative Example 1). Further, the thicknesses of the both and the error range (3σ) thereof were measured by a thickness measuring instrument MG500CT manufactured by Topro Tech. The results are shown in Table 1.

[0028]

[Table 1]

(3) Production of photosensitive resin film A styrylpyridinium-based one-pack type photosensitive emulsion MSP manufactured by Murakami Co., Ltd. was formed on a polyester film having a thickness of 75 μm.
-2 was applied and dried using a wire bar coater to form a photosensitive resin film having a thickness of 25 μm.

(4) Production of screen printing plate (A) Formation of photosensitive resin film layer 2 produced in the above "(2) Sandblasting step"
The photosensitive resin film obtained in the above “(3) Production of photosensitive resin film” is attached to various kinds of cloth plates using water, dried, and then the polyester film is peeled off from the photosensitive resin film. This photosensitive resin film was formed on a stainless steel screen to form a photosensitive resin film layer having a film thickness of 10 μm.

(B) Exposure / Development / Drying Next, a positive film having 30 lines and 30% halftone dot image made of polyester is prepared, and the film surface of the positive film is brought into close contact with the film surface of the above-mentioned photosensitive film layer and 3 kw. Using a metal halide lamp as a light source, UV exposure was performed for 60 seconds from a distance of 80 cm. The exposed plate was developed with a water spray gun, and after drying with warm air, a screen printing plate with halftone dots was obtained.

(5) Evaluation A cellophane tape was attached to the film surface of this screen printing plate, and the nail was rubbed back and forth 10 times with the nail, holding both ends of the cellophane tape, and peeled off all at once and attached to the cellophane tape. I counted the number. The results are shown in the screen and photosensitive emulsion adhesion test in Table 2 below.

[0033]

[Table 2]

Example 2 and Comparative Example 2 (1) Screening process 320 × 320 mm size aluminum die cast frame,
Using a mechanical stretcher, stretches the woven polyester screen with a thickness of 73 μm and 225 mesh,
I made two editions. Next, 360 mesh (wire diameter 16
(μm) woven high-tensile stainless screen was superposed on the inner side of the center of the polyester screen and adhered with an adhesive to make a superposition. Then, the polyester screen in the overlapping portion was removed, and two plates having a combination type upholstery frame were manufactured.

(2) Sandblasting process step One of the above two plates was treated for 30 seconds with a sandblasting machine No. 1000 (alumina) on the printing surface side using a sandblasting machine SC type manufactured by Fuji Manufacturing Co., Ltd. .

On the other hand, the other of the two plates was not sandblasted. As a result, many roughened marks having a roughness of about 1 μm were confirmed on the surface of the stainless steel screen of the sandblasted plate, and it was confirmed that a satin pattern was formed (Example 2). . On the other hand, not sandblasted 3
The 60-mesh stainless screen had a glossy surface, and no satin finish was formed (Comparative Example 2). Also, the thickness of both and the error range (3σ)
Was measured with a thickness measuring device MG500CT manufactured by Topro Tech. The results are shown in Table 3.

[0037]

[Table 3]

(3) Photosensitive emulsion coating step A styrylpyridinium-based 1-pack type photosensitive emulsion MSP-2 manufactured by Murakami Co., Ltd. was applied to the above two plates to repeat coating and drying using a bucket to give a thickness of 10 μm. A photosensitive resin film layer was formed. Next, a silver salt type positive film having a 50 μm line was prepared, the film surfaces were brought into close contact with each other, and a 3 kw metal halide lamp was used as a light source, and 80 c
UV exposure was performed for 40 seconds from a distance of m. The exposed plate was developed with a water spray gun and dried with warm air to obtain a screen printing plate.

Evaluation Results The screen printing plate obtained was a clear plate-making plate having a resolution of 50 μm lines. Next, a screen printing plate that has been sandblasted (Example 2) and a screen printing plate that has not been sandblasted (Comparative Example 2)
The conductor paste was printed on the ceramic substrate using the two plates. As a result, in the sandblasted screen printing plate (Example 2), a stable paste transfer was confirmed from the beginning, and the printing durability was better than that of the unblasted screen printing plate (Comparative Example 2). Met.

[0040]

[Table 4]

Example 3 Example 3 was carried out in the same manner as Example 1 except that the following “grinding process” was carried out in place of the “(2) sandblasting step” of Example 1 above. The evaluation results are shown in Table 5. Grinding process by buffing Non-woven buff material CP wheel 7A made by 3M which rotates
By slowly passing the underside of the VF, a hairline-like pattern composed of a large number of linear concave portions having a roughness of 4 μm was formed. Evaluation results

[0042]

[Table 5]

Example 4 Example 1 was repeated except that in the “(1) gauze step” of Example 1 described above, the following “metal screen formed by electro forming method (electroforming)” was used.
It carried out similarly to. The evaluation results are shown in Table 6. Formed by electroforming (electroforming)
Metal screen material: Electroformed thin plate nickel screen Thickness: 20 μm Pore diameter: 37 μm Evaluation result

[0044]

[Table 6]

[0045]

The screen printing plate obtained by the method for producing a screen printing plate of the present invention as described above has an early stabilization of the cloth tension and a constant screen thickness when the cloth is stretched. In some cases, the adhesiveness between the resist film and the screen may be improved and the dimensional accuracy may be improved, and in printing, the ink permeability may be improved, increasing the paste transfer amount and eliminating waste printing, There are effects that the positional accuracy can be improved, the printed film thickness can be made uniform, and the printing durability can be improved.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Keiji Mase, 5-2-24 Matsue 5-chome, Edogawa-ku, Tokyo Inside the Fuji Manufacturing Co., Ltd. (72) Inventor Yasushi Murakami 5-chome Yokokawa, Sumida-ku, Tokyo No. 3-10 Murakami Co., Ltd. (72) Inventor Fumitaka Obi 5-3 Yokokawa, Sumida-ku, Tokyo No. 3-10 Murakami Co., Ltd. (72) Kazuo Inoue 5-chome, Yokokawa Sumida-ku, Tokyo No. 10 Murakami Co., Ltd. (56) Reference JP-A-6-219071 (JP, A) JP-A-59-220397 (JP, A) JP-A-5-309966 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41N 1/24 G03F 7/12

Claims (2)

(57) [Claims] 1. A latent image is formed by coating a photosensitive emulsion on a surface of a metal screen stretched on a mold and drying it to form a photosensitive resin layer, which is then exposed through a mask. In the production of a screen printing plate for forming an image layer by development, the metal screen is formed by spraying a powder of 100 to 2,000 mesh on its surface and / or buffing. A method for producing a screen printing plate, the surface of which is ground. 2. The method for producing a screen printing plate according to claim 1, wherein the powdery particles are alumina.