Ultrafine filamentary meshless printing screen
By using a knotless metal wire mesh and a tension adjustment system, the problem of knots affecting printing quality and tensile strength is solved, achieving efficient and stable printing results and reducing screen breakage and production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGSU SHENGSI PRECISION TECH CO LTD
- Filing Date
- 2024-07-04
- Publication Date
- 2026-06-26
AI Technical Summary
In existing technologies, screen knots affect printing quality and tensile strength, laser cutting is difficult, leading to easy screen breakage and high cost, and tension is difficult to adjust, affecting printing efficiency and quality.
The metal wire mesh with a knotless structure is woven by cross-weaving of variable-pitch and equal-pitch wires, combined with tension wire mesh, tension adjusting bolts, soft elastic pads and tension sensors to achieve stable and adjustable mesh tension, avoid knot formation, and ensure tension strength and printing quality.
This technology achieves high ink penetration and stable tension in knot-free printing screens, reducing the risk of screen breakage, improving printing quality and lifespan, and lowering production costs.
Smart Images
Figure CN118636572B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a printing plate for solar photovoltaic cells, and more particularly to a tension-balanced and knot-free printing plate for solar photovoltaic cells. Background Technology
[0002] Solar photovoltaic cells absorb sunlight and convert it into electrical energy. The power generation efficiency of a photovoltaic cell is directly related to the shape and quality of its conductive grid lines, which are printed by a screen printing stencil. The printing quality of the screen is mainly affected by the screen knots and the wire diameter.
[0003] The knots formed by the intersections of warp and weft threads on the screen significantly obstruct ink or paste, reducing the ink permeability of the printing screen. Therefore, the ink or paste needs excellent leveling properties to bypass the knots and fuse together during printing, thus preventing issues like broken grids or rough edges, as seen in solar cells. To minimize the impact of knots, current methods involve removing the upper metal wires in the warp or weft direction of the printed pattern. During pattern creation, the fine grid pattern is arranged within the removed grid. While this improves the printability of the fine grid, removing the wires requires approximately 20-30 minutes of laser cutting to cut them completely. Then, water washing is used to remove any remaining wires, ensuring complete removal. The screen must also be inspected to prevent incomplete removal and screen failure. Furthermore, during laser cutting, issues such as equipment instability, incorrect parameter settings, or irregular grid shapes can cause the laser to cut wires in another direction, leading to screen breakage.
[0004] To ensure the photosensitive area of photovoltaic cells, it is desirable for the printed conductive grid lines to be as thin as possible. Currently, the wire diameter of high-quality, high-precision printing screens has reached below 10μm. Under such precise wire conditions, laser cutting of the steel wires has two main drawbacks. First, the reduced number of steel wires affects the tensile strength of the screen, making it prone to cracking and breaking during repeated printing, leading to screen scrap, shortening screen life, and increasing printing costs. Second, ultra-fine and extremely fine metal wires further increase the difficulty of laser cutting, as well as the risk of accidental cutting and the difficulty of removing broken wires.
[0005] Another important factor affecting screen printing performance is screen printing tension. A screen printing stencil consists of a frame and a screen printing plate stretched under tension and glued to the frame. During use, the squeegee side of the screen printing plate is located inside the frame. A squeegee scrapes and presses the ink on the squeegee side, causing the ink to pass through the printing pattern on the screen printing plate and adhere to the substrate. Due to the continuous scraping and pressing of the squeegee during printing, the screen printing plate undergoes elastic deformation. After a period of use, it also undergoes plastic deformation. This plastic deformation will blur the print, inevitably affecting print quality. Therefore, if the screen printing plate, having become loose due to plastic deformation, cannot regain its tension, the entire screen must be discarded. However, because the screen printing plate is glued to the frame, conventional screen printing structures cannot achieve tension recovery. Summary of the Invention
[0006] In view of the above-mentioned shortcomings of the existing technology, the technical problem to be solved by the present invention is to provide an ultra-micro wire knot-free printing screen, which can not only avoid the appearance of wire cross knots in the printing groove area of the screen, but also ensure the tension strength of the screen and ensure stable tension of the screen.
[0007] To solve the above-mentioned technical problems, the present invention provides an ultra-micro wire knotless printing screen, comprising a screen frame, a metal wire mesh, and printing plate grooves. The metal wire mesh is stretched onto the screen frame by a tensioning wire mesh. The printing plate grooves are disposed on the metal wire mesh. The metal wire mesh is woven from variable-pitch wires and equidistant wires. The printing plate grooves are located between two adjacent variable-pitch wires, and at least one of the printing plate grooves has two closely spaced variable-pitch wires disposed on one or both sides of the groove.
[0008] The tensioned wire mesh is bonded to the tensioned wire mesh adhesive strip by the arc-shaped edge of the mesh frame. A soft elastic pad is placed between the tensioned wire mesh adhesive strip and the mesh frame. The tensioning adjustment bolt passes through the soft elastic pad and the tensioned wire mesh to connect the tensioned wire mesh adhesive strip to the mesh frame.
[0009] The tensioned wire mesh is also contacted by a wire mesh tension stabilizing strip, which is movably supported on the mesh frame by a thrust spring; a tension sensor is provided between the arc-shaped edge of the mesh frame and the tensioned wire mesh.
[0010] In the above structure, since the printing plate groove is located between two adjacent variable-pitch wires, it ensures that the printing plate groove is always located between two warp or weft wires, forming a knotless printing plate structure. There are no warp or weft wire intersections in the printing plate groove, reducing the printing resistance to the printing ink and ensuring the ink penetration performance and printing quality of the printing screen. Furthermore, two closely spaced variable-pitch wires are set on the side of the printing plate groove, so there is no need to remove the warp or weft wires that form intersections by laser cutting. This avoids the formation of cut wire residues that affect printing quality and prevents screen breakage caused by laser miscutting of adjacent wires. In particular, this structure can offset specific wires of the equidistant woven mesh to form closely spaced variable-pitch wires without reducing the number of wires in the mesh, thus ensuring sufficient tensile strength of the screen surface. It is especially suitable for printing screens with ultra-fine and ultra-fine meshes.
[0011] Furthermore, since the tension adjusting bolt passes through the soft elastic pad and the tensioning wire mesh, connecting the tensioning wire mesh adhesive strip and the tensioning wire mesh to the mesh frame, turning the tension adjusting bolt allows the tensioning wire mesh adhesive strip to move, thereby pulling the tensioning wire mesh to tighten or loosen, achieving the purpose of adjusting the mesh tension. The tensioning wire mesh adhesive strip is pressed against the soft elastic pad; by using the tension adjusting bolt and the tensioning wire mesh adhesive strip to compress or release the soft elastic pad, both the mesh tension can be adjusted, and the mesh tension can be accurately and controlled in a controlled manner.
[0012] Furthermore, a tension stabilizing strip is positioned at the top of the tensioned wire mesh, and this strip is supported on the frame by a thrust spring. On one hand, this structure maintains stable wire mesh tension. Even if the wire mesh undergoes plastic deformation during long-term repeated use, the thrust spring can compensate for the resulting slack, providing excellent wire mesh tension stabilization. On the other hand, while stabilizing the wire mesh tension, the thrust spring also increases the mesh's elasticity, which is beneficial for improving printing quality.
[0013] Also, because a tension sensor is installed between the curved edge of the screen frame and the tension screen, the tension sensor can provide real-time feedback on the screen tension, so as to adjust and maintain the screen in time and ensure high-quality printing of solar photovoltaic cells.
[0014] In a preferred embodiment of the present invention, the two closely spaced variable-pitch wires include a bias wire and a braided wire. The bias wire is formed by offsetting the braided wire, and the braided wires are equidistant from each other. The printing plate grooves are parallel to the variable-pitch wires; the diameter of the variable-pitch wire and the equidistant wire is 6μm-10μm. This structure ensures that there are no knots formed by the intersection of warp and weft threads in the printing plate grooves, and also maintains the tensile strength of the metal mesh; it is particularly suitable for screen printing with extremely fine or ultra-fine wires.
[0015] In a preferred embodiment of the present invention, the adhesive end of the tensioned wire mesh is bonded to the tensioned wire mesh adhesive strip using adhesive. The length of the strip is greater than or equal to the corresponding side length of the tensioned wire mesh, and two rows of screw holes are provided on the adhesive strip. The soft elastic pad and the tensioned wire mesh adhesive strip are disposed in the corresponding groove of the mesh frame. The tension adjusting bolt can pull the tensioned wire mesh through the tensioned wire mesh adhesive strip, which is pressed tightly against the soft elastic pad. The soft elastic pad is a strip-shaped silicone pad or rubber pad. This allows for convenient and precise adjustment of the mesh tension.
[0016] In a preferred embodiment of the present invention, the screen tensioning and stabilizing strip abuts against the inner side of the tensioned screen, and this strip can support the tensioned screen. The screen tensioning and stabilizing strip is disposed in a corresponding mounting groove of the screen frame, and the thrust spring is supported on the screen tensioning and stabilizing strip by guide posts; the thrust spring is a helical compression spring. The length of the strip-shaped screen tensioning and stabilizing strip is greater than or equal to the corresponding side length of the tensioned screen; at least two guide posts are installed on the screen tensioning and stabilizing strip, and a corresponding thrust spring is fitted on each guide post. This effectively maintains and stabilizes the screen tension, effectively improving the printing quality of the screen.
[0017] In a preferred embodiment of the present invention, the tension sensor is a thin-film pressure sensor with an installation angle α = 45°. The tension sensor is mounted on the arcuate edge of the mesh frame, and at least one force sensor is mounted on each arcuate edge of the mesh frame. This structure can accurately and timely monitor the mesh surface tension, ensuring tension stability. Attached Figure Description
[0018] The present invention’s ultra-micro fiber knotless printing screen will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0019] Figure 1 This is a schematic diagram of a specific embodiment of the ultra-micro filament knotless printing screen of the present invention;
[0020] Figure 2 yes Figure 1 A-A cross-sectional structural diagram;
[0021] Figure 3 yes Figure 1 Enlarged structural diagram of the B-B cross section;
[0022] Figure 4 yes Figure 1 A magnified view of a portion of the surface of a medium-sized metal wire mesh;
[0023] Figure 5 yes Figure 3 Structural diagram of the assembly of the medium wire mesh tension stabilizing strip and spring guide post;
[0024] Figure 6 yes Figure 5 C-C cross-sectional structural diagram;
[0025] Figure 7 yes Figure 6 Front view of the spring guide post;
[0026] Figure 8 yes Figure 7 The left view;
[0027] Figure 9 yes Figure 6 Front view of the tension stabilizing strip for medium wire mesh;
[0028] Figure 10 yes Figure 9 Top view;
[0029] Figure 11 yes Figure 3 Structural diagram of a soft elastic pad;
[0030] Figure 12 yes Figure 11 D-D cross-sectional structural diagram;
[0031] Figure 13 yes Figure 3 Diagram of the bonding strip structure of the medium-tensioned wire mesh;
[0032] Figure 14 yes Figure 13 E-E cross-sectional structural diagram;
[0033] Figure 15 yes Figure 1 A magnified view of a structure of a metal wire mesh surface;
[0034] Figure 16 yes Figure 1 An enlarged view of another structure of the metal wire mesh surface.
[0035] In the diagram, 1—frame, 2—tensioned wire mesh, 3—metal wire mesh, 31—variable pitch wire, 32—equidistant wire, 33—printing plate groove, 34—offset wire, 35—braided wire, 4—tension adjusting bolt, 5—soft elastic pad, 6—adhesive layer, 7—tensioned wire mesh bonding strip, 8—wire mesh tension stabilizing strip, 9—spring guide post, 10—thrust spring, 11—tension sensor, 12—aperture hole, 13—screw hole, 14—scraper side film layer, 15—adhesive side film layer, 16—scraper side groove, 17—adhesive side groove, 18—intermediate film layer, 19—intermediate film layer groove. Detailed Implementation
[0036] like Figure 1 , Figure 2 and Figure 3The ultra-micro wire knotless printing screen shown includes a frame 1, which is a U-shaped aluminum square frame. A stainless steel wire mesh 3 is stretched at the center of the frame 1. Tensioned wire mesh 2, made of polyester mesh, is bonded to the four perimeter of the wire mesh 3. The extended adhesive ends of the tensioned wire mesh 2 wrap around the bottom arc-shaped edges of the corresponding sides of the frame wall of the frame 1 and continue to the tensioned mesh adhesive strip 7. The tensioned wire mesh 2 is bonded to the tensioned mesh adhesive strip 7 via an adhesive layer 6, which is formed using a commonly used adhesive for printing screens. The tensioned mesh adhesive strip 7 and the soft elastic pad 5 are located in grooves on the outer side of the frame wall of the frame 1, and these grooves surround the outer perimeter of the four sides of the frame 1. The tension mesh adhesive strip 7 is installed on the groove wall of the mesh frame 1 through the soft elastic pad 5. The tension wire mesh 2, which is adhered to the tension mesh adhesive strip 7, is located between the tension mesh adhesive strip 7 and the soft elastic pad 5. Two rows of bolt holes are provided on the upper frame surface of the mesh frame 1. The tension adjusting bolt 4 passes through the groove wall of the mesh frame, the soft elastic pad 5, the tension wire mesh 2, and the adhesive layer 6 and is screwed onto the tension mesh adhesive strip 7.
[0037] A tension stabilizing strip 8 is attached to the inner side of the outer frame wall of the mesh frame 1 and abuts against it on the tension mesh 2. A thrust spring 10 is supported on the tension stabilizing strip 8. The tension stabilizing strip 8 is supported in a corresponding groove of the mesh frame 1 by several thrust springs 10. Each thrust spring 10 is supported on the tension stabilizing strip 8 by a corresponding spring guide post 9. The thrust spring 10 is a helical compression spring. The groove accommodating the tension stabilizing strip 8 and the groove accommodating the soft elastic pad 5 and the tension mesh adhesive strip 7 are both arranged around the outer mesh wall of the mesh frame 1, and the two grooves are parallel to each other.
[0038] A tension sensor 11 is installed between the curved edge of the frame wall around which the tensioned wire mesh 2 passes and the tensioned wire mesh 2. The curved edge of the frame wall is a quarter-cylindrical surface, and the radius R of the cylinder containing this cylindrical surface is one-third of the thickness of the frame wall. The installation angle α of the tension sensor 11 is 45°, which is the angle between the installation center line of the tension sensor 11 and the bottom (or top) surface of the wire mesh frame 1. The tension sensor 11 is embedded in the wire mesh frame 1 and is a thin-film pressure sensor. This thin-film pressure sensor has a simple structure, high measurement accuracy, and fast response speed, which is beneficial for the installation of the tension sensor 11 and the monitoring of the wire mesh tension.
[0039] like Figure 1 , Figure 4 As shown, the metal wire mesh 3 is woven from variable-pitch wires 31 and equidistant wires 32, which are perpendicularly interwoven. The variable-pitch wires 31 and equidistant wires 32 are stainless steel wires with a diameter between 6μm and 10μm, or they can be nickel wires. Figure 4In the screen printing, the weft threads are equidistant threads 32, and the warp threads are variable-pitch threads 31. The variable-pitch threads 31 include braiding threads 35 and offset threads 34, with the offset threads 34 formed by offsetting and shifting the braiding threads 35. When a warp thread (as shown by the dotted line in the figure) happens to be located at the position of the printing plate groove 33 and intersects with the equidistant weft thread 32 to form a mesh, an offset comb with several pins is used to move and shift the warp thread closer to another warp thread to form a parallel thread structure. These two closely spaced variable-pitch threads 31 include one offset thread 34 formed by shifting and shifting, and the other is the braiding thread 35 used in screen weaving, which is equidistantly spaced. Therefore, the printing plate groove 33 is parallel to the variable-pitch threads 31.
[0040] like Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10 As shown, the wire mesh tension stabilizing strip 8 is a long strip of aluminum. One surface of this strip is the top contact surface that contacts the tensioned wire mesh 2, and the other surface has several circular blind holes evenly spaced for fixing and installing spring guide posts 9. A thrust spring 10 can be fitted onto each spring guide post 9. The spring guide post 9 can be a stepped short cylinder, or it can be a short cylinder. The length of the wire mesh tension stabilizing strip 8 is equal to the corresponding side length of the tensioned wire mesh 2, or it can be slightly longer than its corresponding side length.
[0041] like Figure 11 , Figure 12 As shown, the soft elastic pad 5 is a long strip of silicone pad, or it can be a rubber pad or other soft elastic pad. Two rows of through holes 12 are provided on the soft elastic pad 5. The holes 12 are used to pass through the tension adjusting bolt 4.
[0042] like Figure 13 , Figure 14 As shown, the tension mesh adhesive strip 7 is a long strip of aluminum plate. Two rows of screw holes 13 are provided on the tension mesh adhesive strip 7 for screwing the tension adjustment bolts 4. The length of the tension mesh adhesive strip 7 and the soft elastic pad 5 is equal to the corresponding side length of the tension mesh 2, or slightly longer than the corresponding side length of the tension mesh 2.
[0043] like Figure 15The illustrated screen printing metal mesh structure includes a squeegee-side film layer 14 coated on the squeegee-side G surface of the metal mesh 3. This squeegee-side film layer 14 is formed by coating and photosensitive emulsion. The outer surface of the squeegee-side film layer 14 is the squeegee surface, where the squeegee directly contacts the squeegee surface during printing. Several squeegee-side grooves 16 are designed on the squeegee-side film layer 14 according to the printing pattern, and the cross-section of each groove is a rectangular through groove. An adhesive-side film layer 15 is coated on the lower surface of the printing side T of the metal mesh 3. The adhesive-side film layer 15 is made of polymer films such as PET, PE, PI, PU, PVC, and PS. Similarly, several adhesive-side grooves 17 are designed on the adhesive-side film layer 15 according to the printing pattern. The center lines of the corresponding squeegee side groove 16 and the adhesive side groove 17 are located on the same straight line, and the groove width of the squeegee side groove 16 is greater than the groove width of the adhesive side groove 17, thus forming a stepped cross-section printing plate groove 33, which is beneficial to improve the ink penetration performance of printing, improve printing quality, and is more conducive to improving the aspect ratio of the printing electrode paste. It is also beneficial to reduce the light-blocking area of the printing grid lines and effectively reduce the consumption of printing paste.
[0044] like Figure 16 The diagram illustrates a screen printing mesh structure. An intermediate film layer 18 is coated on the printing side (T) of the metal mesh 3. This intermediate film layer 18 is formed by coating and photosensitive emulsion. Several intermediate film layer grooves 19 are designed on the intermediate film layer 18 according to the printing pattern, and the cross-section of each groove 19 is a rectangular through slot. A printing side film layer 15 is coated on the intermediate film layer 18. The printing side film layer 15 is made of polymer films such as PET, PE, PI, PU, PVC, and PS. Several printing side grooves 17 are provided on the printing side film layer 15, and the width of the groove openings of the intermediate film layer grooves 19 is greater than the width of the groove openings of the printing side grooves 17. The intermediate film layer 18 and the printing side film layer 15 can be polymer film adhesive layers or photosensitive emulsion coating layers.
[0045] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. Many modifications and variations can be made based on the content of this specification. The selection and detailed description of these embodiments are intended to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize it. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
Claims
1. A micro-wire knotless printing screen, comprising a frame (1), a wire mesh (3), and printing plate grooves (33), wherein the wire mesh (3) is stretched onto the frame (1) by a tensioning wire mesh (2), and the printing plate grooves (33) are disposed on the wire mesh (3), characterized in that: The metal mesh (3) is woven from variable-pitch wires (31) and equidistant wires (32). The printing plate groove (33) is located between two adjacent variable-pitch wires (31), and at least one printing plate groove (33) has two closely spaced variable-pitch wires (31) on one or both sides of the groove. The two closely spaced variable-pitch wires (31) include offset wires (34) and braided wires (35). The offset wires (34) are formed by offsetting the braided wires, and the braided wires (35) are equidistant from each other. The tensioned wire mesh (2) is bonded to the tensioned wire mesh adhesive strip (7) by the arc-shaped edge of the wire mesh frame (1). A soft elastic pad (5) is placed between the tensioned wire mesh adhesive strip (7) and the wire mesh frame (1). The tension adjusting bolt (4) passes through the soft elastic pad (5) and the tensioned wire mesh (2) to connect the tensioned wire mesh adhesive strip (7) to the wire mesh frame (1). The tension adjusting bolt (4) can pull the tensioned wire mesh (2) through the tensioned wire mesh adhesive strip (7). Tightening the tension adjusting bolt (4) can move the tensioned wire mesh adhesive strip (7) and then drag the tensioned wire mesh (2) to tighten or loosen. The tensioned wire mesh adhesive strip (7) is pressed against the soft elastic pad (5). The tensioned wire mesh (2) is also contacted by a wire mesh tension stabilizing strip (8), which is movably supported on the wire mesh frame (1) by a thrust spring (10); the wire mesh tension stabilizing strip (8) is in contact with the inner side of the tensioned wire mesh (2), and the wire mesh tension stabilizing strip (8) can support the tensioned wire mesh (2). A tension sensor (11) is provided between the arc-shaped edge of the mesh frame (1) and the tensioned wire mesh (2), and the installation angle of the tension sensor (11) is α=45°.
2. The ultra-micro fiber knotless printing screen according to claim 1, characterized in that: The printing plate groove (33) is parallel to the variable pitch wire (31); the wire diameter of the variable pitch wire (31) and the equidistant wire (32) is 6μm-10μm.
3. The ultra-micro fiber knotless printing screen according to claim 1, characterized in that: The bonding end of the tension wire mesh (2) is bonded to the tension wire mesh bonding strip (7) by adhesive. The length of the tension wire mesh bonding strip (7) is greater than or equal to the corresponding side length of the tension wire mesh (2). Two rows of screw holes (13) are provided on the tension wire mesh bonding strip (7).
4. The ultra-micro fiber knotless printing screen according to claim 1 or 3, characterized in that: The soft elastic pad (5) and the tension mesh adhesive strip (7) are set in the corresponding groove of the mesh frame (1). The soft elastic pad (5) is a strip-shaped silicone pad or rubber pad.
5. The ultra-micro fiber knotless printing screen according to claim 1, characterized in that: The wire mesh tension stabilizing strip (8) is set in the corresponding mounting groove of the wire mesh frame (1), and the thrust spring (10) is supported on the wire mesh tension stabilizing strip (8) by the guide post (9). The thrust spring (10) is a helical compression spring.
6. The ultra-micro fiber knotless printing screen according to claim 1 or 5, characterized in that: The length of the strip-shaped wire mesh tension stabilizing strip (8) is greater than or equal to the corresponding side length of the tensioned wire mesh (2); at least two guide posts (9) are installed on the wire mesh tension stabilizing strip (8), and a corresponding thrust spring (10) is fitted on each guide post (9).
7. The ultra-micro fiber knotless printing screen according to claim 1, characterized in that: The tension sensor (11) is a thin-film pressure sensor.
8. The ultra-micro fiber knotless printing screen according to claim 1, characterized in that: The tension sensor (11) is installed on the arc frame edge of the mesh frame (1), and at least one force sensor (11) is installed on each side arc frame edge of the mesh frame (1).