A processing method of a composite printing screen

Abstract

The application provides a processing method of a composite printing screen plate, which reduces the manufacturing cost of the printing screen plate with a metal sheet structure, so that the metal sheet printing screen plate can be applied to the silk screen industry. The method comprises the following steps: S1, manufacturing a full-opening single-layer metal sheet printing plate, cleaning the metal sheet, and then sequentially obtaining an ink storage groove and a slurry outlet groove on the center printing area of the S surface of the metal sheet through an etching process, and then obtaining a raised layer hole groove on the P surface of the metal sheet through the etching process; S2, superimposing the metal sheet and a PI film to form a composite printing plate, and obtaining the composite printing plate by hot pressing the PI film on the S surface of the metal sheet at high temperature; S3, screen stretching, hot melting the composite printing plate obtained in the step S2 on the screen body of a prepared false frame through high-temperature hot melting glue, and removing the overlapped screen body of the false frame and the printing area of the composite printing plate; S4, top screen; and S5, glue removal.

Description

Technical Field

[0001] This invention relates to the field of printing technology, specifically to a method for processing composite printing screens. Background Technology

[0002] With the development of screen printing plates, existing technologies have gradually developed the ability to manufacture metal printing sheets through electroforming. However, obtaining a single-layer metal sheet with full openings through electroforming is costly, and if the slots of a single metal printing sheet are not positioned correctly or the processing fails, the entire metal printing sheet will be scrapped, making the finished product of the metal printing sheet expensive. Therefore, although metal printing sheets have been successfully developed, the existing electroforming manufacturing method is not commercially viable due to its cost. For this reason, there is an urgent need to develop an economically viable processing method for printing screens with metal sheets. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a processing method for a composite printing screen, which reduces the manufacturing cost of printing screens with metal sheet structures, enabling the application of metal sheet printing screens in the screen printing industry.

[0004] A method for processing a composite printing screen, which uses metal sheets and PI film to composite and process a composite printing plate, is characterized by comprising the following steps: The S1 fully open single-layer metal sheet printing board is manufactured by cleaning the metal sheet, and then obtaining the ink storage tank and ink outlet tank in sequence through etching process in the central printing area of ​​the S side of the metal sheet. After that, the padding layer hole groove is obtained through etching process on the P side of the metal sheet. S2, Metal sheet laminated with PI film, composite printing board is obtained by high temperature hot pressing of PI film on the S surface of metal sheet; S3. The composite printing plate obtained in step S2 is glued to the prepared dummy frame's mesh body using high-temperature hot melt adhesive, and the overlapping mesh bodies of the dummy frame's mesh body and the printing area of ​​the composite printing plate are removed. For S4 top screen printing, place the completed dummy frame on the platform of the top screen printing equipment. Fix a metal frame in the middle of the platform, then drive the metal frame to rise so that the upper edges of the metal frame and the mesh body of the dummy frame are tightly attached. After reaching the predetermined tension, use instant adhesive to stick the completed composite printing plate and the outer mesh body to the pre-placed metal frame. After the adhesive is completely dry, cut off the excess screen along the metal frame. S5 adhesive removal is used to remove the portion of the PI film on the S-surface of the metal sheet that is obstructing the printing channel for the parts of the graphic that need to be printed, thus ensuring a smooth and reliable printing channel.

[0005] Its further features are: The PI film and metal sheet are composited with a built-in hot melt adhesive layer. The hot pressing temperature during the composite process is 100-200℃ and the hot pressing time is 30-40min, ensuring reliable composite of the PI film and metal sheet, with the PI film completely covering the central printing area of ​​the metal sheet. The PI film has a pre-formed texture on its exposed surface after lamination, which eliminates the need to process textures on the surface of the metal sheet, thus reducing manufacturing costs. The thickness of the metal sheet is 0.002 mm to 0.4 mm; The metal sheet is made of stainless steel, copper foil, nickel foil, nickel-cobalt alloy, or other metal materials suitable for precision etching. When the thickness of the metal sheet is no greater than 0.02 mm, in step S1, after cleaning the metal sheet, a composite substrate film is required. The substrate film is used to prevent the metal sheet from being bent or scratched during the operation. The substrate film is shrunken relative to the size of the metal sheet, thereby reserving the composite attachment edge for the mesh. When the thickness of the metal sheet is no greater than 0.02 mm, step S1 is as follows: after cleaning the metal sheet, a substrate film is laminated on the P side. Then, an ink storage tank and an ink discharge tank are sequentially obtained on the S side of the metal sheet through an etching process. Afterward, a padding layer clearance hole groove is formed on the substrate film through a laser process. Then, a padding layer hole groove is obtained on the P side of the metal sheet through the padding layer clearance hole groove through an etching process. In step S2, after the PI film and the metal sheet are laminated, the substrate film is removed. In step S1, the ink storage tank and the slurry outlet tank on the S side of the metal sheet are obtained by independent etching processes. Each etching process includes coating, photolithography, development, etching, cleaning and drying. In step S1, the padding layer grooves on the P side of the metal sheet are obtained by etching after flipping the metal sheet. The padding layer grooves are set to expand outward relative to both sides of the slurry outlet, so that there is a fluid channel between the slurry outlet and the substrate to be printed, so that the slurry can be accurately and reliably printed onto the substrate surface. In step S3, the dummy frame is obtained in advance by screen printing. Since the printing area of ​​the PI film needs to be de-adhesive in step S5, and the upper surface of the metal printing sheet is covered by the PI film, it is not necessary to obtain the texture on the S side of the metal sheet by etching process during the production of the metal printing sheet. In step S3, the area of ​​the dummy frame's mesh body is larger than the area of ​​the metal sheet, and the outer periphery of the P-side of the composite printed board's metal sheet is adhered to the dummy frame's mesh body through a PI adhesive layer.

[0006] Using this invention, the metal sheet is etched twice on the S-side to obtain the ink reservoir and the paste outlet, and etched on the P-side to obtain the padding layer perforations. Then, a composite printing plate is formed by laminating a PI film onto the S-side of the metal sheet. A dummy frame is then used to stretch the composite printing plate, and the metal frame and dummy frame are assembled to complete the top screen. Finally, the PI film covering the surface of the ink reservoir is removed through a descaling process, allowing the paste to flow into the ink reservoir through the perforations of the PI film and then fall through the padding layer perforations along the paste outlet to the substrate surface. The finished metal coil is then punched to obtain a metal sheet of the desired shape. The sheet metal is then etched to obtain the corresponding ink reservoir, paste outlet, and padding layer slots. Etching is a mature and cost-effective process that significantly reduces the manufacturing cost of the metal sheet. By laminating a PI film onto the S-side of the etched metal sheet, and using the exposed surface of the PI film to guide the rapid flow of the paste, the ink reservoir, paste outlet, and padding layer slots can be pre-designed according to the shape to be screen printed during the processing. This reduces the overall manufacturing cost of the printing screen and allows metal sheet printing screens to be used in the screen printing industry. Attached Figure Description

[0007] Figure 1 This is a longitudinal cross-sectional view of the metal sheet of the present invention; Figure 2 This is a schematic diagram of the substrate film composite process in step S1 of a specific embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the composite printing plate of the present invention; Figure 4 This is a top view schematic diagram of a printing screen plate obtained according to a specific embodiment of the present invention; The names corresponding to the serial numbers in the diagram are as follows: Metal sheet 10, ink storage tank 101, ink discharge tank 102, padding layer hole groove 103, PI film 20, hot melt adhesive layer 21, flow channel 201, mesh body 30, metal frame 40, substrate film 50. Detailed Implementation

[0008] A method for processing a composite printing screen involves using metal sheet 10 and PI film 20 to fabricate a composite printing plate. (See attached image.) Figures 1-4 It includes the following steps: S1 Fully Open Single-Layer Metal Sheet Printing Board is made by cleaning the metal sheet 10, and then obtaining the ink storage tank 101 and the ink discharge tank 102 in sequence through etching process in the central printing area of ​​the S side of the metal sheet 10. Then, the pad layer hole groove 103 is obtained through etching process on the P side of the metal sheet 10. S2, Metal sheet 10 is laminated with PI film 20, and composite printing plate is obtained by hot pressing PI film 20 on S surface of metal sheet 10 at high temperature; S3. The composite printing plate obtained in step S2 is glued to the prepared dummy frame mesh body 30 using high-temperature hot melt adhesive, and the overlapping part of the dummy frame mesh body and the printing area of ​​the composite printing plate is removed. For S4 top screen printing, the completed dummy frame is placed on the platform of the top screen printing equipment. A metal frame 40 is fixed in the center of the platform. Then, the metal frame 40 is driven to rise, so that the upper edges of the metal frame 40 and the mesh body 30 of the dummy frame are tightly attached. After reaching the predetermined tension, the completed composite printing plate and metal mesh are glued to the pre-placed metal frame using instant adhesive. After the adhesive is completely dry, the excess mesh is cut off along the metal frame. S5 adhesive removal uses a laser to remove the portion of the PI film 20 that obstructs the printing channel, ensuring a smooth and reliable printing process for the areas within the graphic that require printing.

[0009] In practice, the thickness of the metal sheet 10 is 0.002mm to 0.4mm; the shape of the metal sheet 10 is obtained according to actual needs. The metal sheet 10 is made of stainless steel, copper foil, nickel foil, nickel-cobalt alloy, or other metal materials suitable for precision etching. When the thickness of the metal sheet 10 is not greater than 0.02mm, in step S1, after cleaning the metal sheet, a composite substrate film 50 is required. The substrate film 50 is used to prevent the metal sheet from being bent or scratched during the operation. The substrate film 50 is shrunken relative to the size of the metal sheet 10, thereby reserving the composite attachment edge for the mesh. When the thickness of the metal sheet 10 is not greater than 0.02 mm, step S1 is to clean the metal sheet 10 and then laminate the substrate film 50 on the P side. Then, on the S side of the metal sheet 10, an ink storage tank 101 and an ink discharge tank 102 are sequentially obtained through an etching process. After that, a padding layer clearance hole groove is formed on the substrate film 50 through a laser process. Then, a padding layer hole groove 103 is obtained through an etching process on the P side of the metal sheet 10 through the padding layer clearance hole groove. In step S2, after the PI film 20 and the metal sheet 10 are laminated, the substrate film 50 is removed.

[0010] In practical implementation, it is used for photovoltaic cell printing. The metal sheet 10 is made of 0.02mm 301B stainless steel. The metal sheet 10 is pre-processed to obtain a corresponding 30cm*30cm square shape, which includes the following steps: S1 fully open single-layer metal sheet printing plate fabrication; S101 cleaning uses a fully automatic tunnel cleaning machine to degrease and clean the surface of the metal sheet 10. The first cleaning uses a weak alkaline cleaning agent spraying method, the second cleaning uses pure water rinsing, the third process is to dry the metal sheet, and the fourth process is to collect the material. S102, A PET material substrate film 50 is laminated on the P side of the metal sheet 10. The substrate film 50 is applied at room temperature and the size of the substrate film 50 is not larger than the metal sheet 10. S103, the ink storage tank 101 is processed by the first etching process; S1031, First coating: The coating material is precision photoresist. The coating is carried out by a fully automatic roller coating method. A precision photoresist with a thickness of 0.04mm is coated on the S side of the metal sheet through a tunnel coating and baking integrated machine. The coating speed is 0.4m / min and the baking temperature is 50℃. S1032, the first photolithography, uses LDI photolithography equipment with a precision of 0.001mm. The ink reservoir is photolithographically etched on the metal surface covered with photoresist. The width of the ink reservoir is 0.06mm-0.3mm. The photolithography of the ink reservoir is performed by expanding the pattern outward on one side. S1033, first development, the development adopts a fully automatic tunnel development line; the development sequence includes the first pure water rinse, the second developer rinse, the third pure water cleaning, and the fourth drying. S1034, first etching, ink reservoir depth etched 0.008-0.01mm; S1035, washing and drying, using a tunnel-type automatic washing machine for rinsing, drying temperature 45±5℃, and circulating air drying; S104, the second etching process produces the slurry tank 102; S1041, Second coating: The coating material is precision photoresist. The coating is carried out by a fully automatic roller coating method. A precision photoresist with a thickness of 0.04mm is coated on the S side of the metal sheet through a tunnel coating and baking integrated machine. The coating speed is 0.4m / min and the baking temperature is 50℃. S1042, the second photolithography, uses LDI photolithography equipment with a precision of 0.001mm. The photoresist-covered ink reservoir is photolithographically etched with a paste-out groove width of 0.008-0.01mm. S1043, second development, the development adopts a fully automatic tunnel development line; the development sequence includes the first pure water rinse, the second developer rinse, the third pure water cleaning, and the fourth drying. S1044, second etching, slurry outlet depth 0.008-0.01mm, the bottom of the slurry outlet and the P surface are left with a distance L, L is 0.001-0.002mm; S1045, washing and drying, using a tunnel-type automatic washing machine for rinsing, drying temperature 45±5℃, and circulating air drying; S105, forming a pad layer clearance groove on the substrate film 50; S1051 flips the metal sheet 10 so that the substrate film 50 is arranged facing upwards; S1052, a padding layer clearance groove is obtained on the substrate film 50 through a preset laser processing path. The laser power will not affect the metal sheet 10. The padding layer clearance groove is set according to the shape of the padding layer clearance groove. In order to prevent shading and offset, the pattern of the padding layer clearance groove is expanded outward on one side. The specific processing laser parameters are shown in Table 1 and Table 2.

[0011] Table 1

[0012] Table 2 S1053, Cleaning: After laser cutting, gently wipe with an alcohol-moistened dust-free sponge to remove carbonized dust from the surface. After wiping, rinse with a tunnel-type fully automatic cleaning machine and dry. S106, the third etching process is used to process the high-layer hole groove 103 of the pad; S1061, Third coating: The coating material is precision photoresist. The coating is carried out by a fully automatic roller coating method. A precision photoresist with a thickness of 0.04mm is coated on the P-side substrate film of the metal sheet 10 through a tunnel coating and baking integrated machine. The coating speed is 0.4m / min and the baking temperature is 50℃. S1062, the third photolithography, uses LDI photolithography equipment with a precision of 0.001mm. Photolithography is performed on the substrate film surface covered with photoresist to form pad high layer holes. The pad high layer holes are set to be extended outward relative to the ink storage tank. S1063, third development, the development adopts a fully automatic tunnel development line; the development sequence includes the first pure water rinse, the second developer rinse, the third pure water cleaning, and the fourth drying. S1064, third etching, depth L of pad layer hole groove, pad layer hole groove penetrates the corresponding position of slurry outlet groove 102. S1065, washing and drying, using a tunnel-type automatic washing machine for rinsing, drying temperature 45±5℃, and circulating air drying; S2 metal sheet 10 is laminated with PI film 20 to obtain a composite printing board. The surface of the composite of PI film 20 and metal sheet 10 has a hot melt adhesive layer 21. The hot pressing temperature of PI film 20 and metal sheet is 100-200℃ and the hot pressing time is 30-40min to ensure reliable composite of PI film 20 and metal sheet 10. PI film 20 completely covers the central printing area of ​​metal sheet, and the exposed surface of PI film 20 has a pre-set texture. After the composite is completed, the substrate film 50 is removed. S3. The composite printing plate obtained in step S2 is glued to the prepared dummy frame mesh body 30 using high-temperature hot melt adhesive, and the overlapping part of the dummy frame mesh body 30 and the printing area of ​​the composite printing plate is removed. In step S3, the dummy frame is obtained in advance by stretching a wire mesh; In step S3, the area of ​​the screen of the dummy frame is larger than the area of ​​the metal frame, and the outer periphery of the P side of the metal sheet of the composite printing plate is adhered to the screen body of the dummy frame through the PI adhesive layer. For the S4 top net, the composited dummy frame is placed on the platform of the top net equipment. A metal frame 40 is fixed in the middle of the platform. Then, the metal frame 40 is driven to rise, so that the upper edges of the metal frame 40 and the net body 30 of the dummy frame are tightly attached. After reaching the predetermined tension, the composited metal sheet 10 and PI film 20 are transferred and glued to the pre-placed metal frame 40 through the outer perimeter net body 30 using instant adhesive. After the adhesive is completely dry, the excess net body 30 is cut off along the metal frame 40. The metal frame 40 is a 45cm*45cm electroformed aluminum frame. In specific implementation, the tension can be adjusted according to customer needs. It is also possible to choose to have force in any of the X and Y directions, with no tension or slight tension in the other direction. Metal sheet 10 can be placed in the center or off-center according to customer needs; S5 adhesive removal targets the areas within the graphic that require printing. It uses a laser to remove the area of ​​the upper PI film 20 corresponding to the area above the ink reservoir 101, ensuring a smooth and reliable printing channel. The laser adhesive removal process does not affect the adhesion of the hot melt adhesive on the remaining parts of the PI film 20. S501, The graphic of the ink storage tank 101 etched on the metal sheet is generated into a CAD format drawing by scanning equipment; S502 Cutting: Using the scanned CAD format drawing, the PI film 20 corresponding to the shape of the ink reservoir 101 is removed from the S side of the screen using a P-second ultraviolet laser to obtain the flow channel 201. To prevent omissions or misalignments, the removal range is extended outward by 0.1mm on each side of the graphic. The laser parameters used for removal are shown in Table 3.

[0013] Table 3 After S503 cleaning and cutting, gently wipe the surface with a dust-free sponge dampened with alcohol to remove carbonized dust from the cutting process. After wiping, rinse with a tunnel-type fully automatic cleaning machine using two stages of pure water at normal water pressure. Then, perform a drying process. After drying, the metal surface must be free of water stains, dirt, or other foreign matter.

[0014] In a specific embodiment, the main component of the etching solution in each etching process is ferric chloride (FeCl3). The additives include corrosion inhibitors to prevent seepage, surfactants as wetting agents, and stabilizers to prevent sedimentation. The etching rate for 301B stainless steel in an environment of 40-50℃ is 0.02-0.08 mm / min. The etching time is determined according to the etching thickness, and the etching operation is carried out by spraying the etching solution.

[0015] In the text, S side refers to the squeegee side surface, and P side refers to the printing substrate side surface.

[0016] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0017] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for processing a composite printing screen, comprising fabricating a composite printing plate using metal sheets and PI film, characterized in that, It includes the following steps: The S1 fully open single-layer metal sheet printing board is made by cleaning the metal sheet, and then obtaining the ink storage tank and ink outlet tank in sequence through etching process in the central printing area of ​​the S side of the metal sheet. Then, the padding layer hole groove is obtained through etching process on the P side of the metal sheet. S2, Metal sheet laminated with PI film, composite printing board is obtained by high temperature hot pressing of PI film on the S surface of metal sheet; S3. The composite printing plate obtained in step S2 is glued to the prepared dummy frame mesh body using high-temperature hot melt adhesive, and the overlapping mesh body of the dummy frame mesh body and the printing area of ​​the composite printing plate is removed. For S4 top screen printing, place the completed dummy frame on the platform of the top screen printing equipment. Fix a metal frame in the middle of the platform, then drive the metal frame to rise so that the upper edges of the metal frame and the mesh body of the dummy frame are tightly attached. After reaching the predetermined tension, use instant adhesive to stick the completed composite printing plate and the outer mesh body to the pre-placed metal frame. After the adhesive is completely dry, cut off the excess screen along the metal frame. S5 adhesive removal is a laser-based method used to remove the portion of the PI film on the S-surface of a metal sheet that is obstructing the printing channels for areas within a graphic that require printing.

2. The processing method of a composite printing screen according to claim 1, characterized in that: The PI film and metal sheet are composited with a built-in hot melt adhesive layer. The hot pressing temperature during the composite process is 100-200℃ and the hot pressing time is 30-40 minutes to ensure reliable composite of the PI film and metal sheet. The PI film completely covers the central printing area of ​​the metal sheet.

3. The processing method of a composite printing screen according to claim 1, characterized in that: The PI film has a textured surface pre-formed on its exposed surface after lamination.

4. The processing method of a composite printing screen according to claim 1, characterized in that: The thickness of the metal sheet is 0.002 mm to 0.4 mm.

5. The processing method of a composite printing screen according to claim 1, characterized in that: When the thickness of the metal sheet is no more than 0.02 mm, in step S1, after cleaning the metal sheet, a composite substrate film is required. The substrate film is used to prevent the metal sheet from being bent or scratched during the operation. The substrate film is shrunken relative to the size of the metal sheet, thereby reserving the composite attachment edge for the mesh.

6. The processing method of a composite printing screen according to claim 1, characterized in that: When the thickness of the metal sheet is no more than 0.02 mm, step S1 is to clean the metal sheet and then laminate a substrate film on the P side. Then, on the S side of the metal sheet, an ink storage tank and an ink discharge tank are sequentially obtained through an etching process. After that, a padding layer clearance hole groove is formed on the substrate film through a laser process. Then, a padding layer hole groove is obtained on the P side of the metal sheet through an etching process. In step S2, after the PI film and the metal sheet are laminated, the substrate film is removed.

7. The processing method of a composite printing screen according to claim 1, characterized in that: In step S1, the ink storage tank and ink discharge tank on the S side of the metal sheet are obtained by independent etching processes. Each etching process includes coating, photolithography, development, etching, cleaning and drying.

8. The processing method of a composite printing screen according to claim 1, characterized in that: In step S1, the padding high-level hole groove on the P side of the metal sheet is obtained by turning the metal sheet over and then etching it. The padding high-level hole groove is set outward relative to the two sides of the slurry outlet, so that there is a fluid channel between the slurry outlet and the substrate to be printed, so that the slurry can be accurately and reliably printed onto the substrate surface.

9. The processing method of a composite printing screen according to claim 1, characterized in that: In step S3, the dummy frame is obtained in advance by screen printing. Since the printing area of ​​the PI film needs to be de-adhesive in step S5, and the upper surface of the metal printing sheet is covered by the PI film, it is not necessary to obtain the texture on the S side of the metal sheet by etching process during the production of the metal printing sheet.

10. The processing method of a composite printing screen according to claim 1, characterized in that: In step S3, the area of ​​the dummy frame's mesh body is larger than the area of ​​the metal sheet, and the outer periphery of the P-side of the composite printed board's metal sheet is adhered to the dummy frame's mesh body through a PI adhesive layer.

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