A printing screen and a method of manufacturing the same, a screen cloth rotation method and apparatus

Abstract

The application discloses a printing screen plate and a manufacturing method thereof, a screen cloth rotating method and equipment. The screen plate comprises a screen frame and a screen cloth fixed on the screen frame. The screen cloth is interwoven by warp and weft and is formed with a plurality of knots. The diameters of the warp and the weft at the knots are respectively reduced and become smaller. The warp and the weft are not perpendicular to each other. At least one predetermined yarn-removing pattern area is arranged on the screen cloth. The predetermined yarn-removing pattern area only comprises the warp or the weft. A polymer material layer is arranged on the screen cloth. At least one opening pattern is arranged in the area corresponding to the predetermined yarn-removing pattern area on the polymer material layer. The opening pattern only comprises the warp or the weft in the predetermined yarn-removing pattern area. The warp and the weft at the knots are thinned, which is beneficial to the relative rotation between the warp and the weft. Only the warp or the weft is left in the opening pattern and has a certain angle with the ink printing direction. The ink resistance is low. The printed pattern has high precision, low ups and downs and can be adapted to various shapes of the opening pattern.

Description

Technical Field

[0001] This invention relates to the field of printing screen technology, and more particularly to a printing screen that can adjust the angle of warp and weft threads according to a graphic, a method for manufacturing the same, and a method and device for rotating the warp or weft threads in the screen fabric. Background Technology

[0002] In existing technologies, screen printing is commonly used to print electrode patterns for solar cells, and the required patterns are becoming increasingly refined. However, the intersections of the warp and weft threads in the screen printing are prone to clogging. Therefore, current technologies employ a knotless design, opening the pattern between two parallel warp or weft threads. This increases ink permeability, but results in uneven lines after printing, which can easily lead to broken lines or excessive impedance.

[0003] On the other hand, such as Figure 1 This schematic illustration illustrates a prior art printing screen structure, in which the printing screen 2 includes a frame 21, a mesh fabric 22, and a polymer material layer 23 formed on the mesh fabric 22, with an opening pattern 231 formed on the polymer material layer 23. In the prior art, the warp threads 221 in the opening pattern 231 are etched away using an etching or laser process to avoid the formation of a knot between the warp and weft threads 221 in the opening pattern 231. However, in this prior art printing screen structure, because the opening pattern 231 is... Figure 1 The solar finger line shown has a straight section on the left side of the L-shaped pattern that is perpendicular to the latitude line 222. This causes the ink to be blocked by the latitude line during printing, resulting in a large unevenness in the printed pattern and making the printed finger line pattern have excessive impedance, leading to low power generation efficiency. Similarly, if the warp line 221 in the opening pattern 231 is removed, only the latitude line 222 will remain in the bottom edge of the L-shape. This will also cause the ink to be blocked by the latitude line 222 during printing, similarly resulting in excessive impedance and low power generation efficiency.

[0004] As can be seen from the existing technology described above, current printing screen structures with mutually perpendicular warp and weft yarns and no knots can print patterns with relatively fine line widths in open patterns, but this does not increase the efficiency of solar finger electrodes, and some patterns are not suitable for screen structures with mutually perpendicular warp and weft yarns. Therefore, there is a need to provide a printing screen with rotating warp and weft yarns that can match the pattern, achieving a knot-free open pattern while also printing lines with lower height differences. Summary of the Invention

[0005] The purpose of this invention is to provide a printing screen and its manufacturing method. By thinning the warp and weft threads at the mesh knots, it is easier to rotate the warp or weft threads, causing them to rotate at an angle and no longer be perpendicular to each other. This creates a printing screen with a slanted mesh, ensuring that only the warp or weft threads included in the opening pattern on the slanted mesh are in a slanted mesh state, i.e., at a certain angle to the ink printing direction. This reduces ink resistance, improves the accuracy of the printed image, reduces unevenness, and allows for the adjustment of the rotation angle between the warp and weft threads to accommodate various opening patterns. The invention also provides a method and apparatus for rotating the warp or weft threads in the mesh.

[0006] To achieve the purpose of the invention, the present invention provides a printing screen, which includes a screen frame and a mesh fabric fixed on the screen frame. The mesh fabric includes a plurality of parallel warp threads and a plurality of parallel weft threads. The warp threads and the weft threads interweave to form a plurality of knots. At the knots, the diameter of the warp threads becomes thinner and the diameter of the weft threads becomes thinner. The warp threads and the weft threads are not perpendicular to each other. The mesh fabric has at least one predetermined yarn removal pattern area, which includes only warp threads or weft threads. A polymer material layer is provided on one side of the mesh fabric. At least one opening pattern is provided on the polymer material layer in the area corresponding to the predetermined yarn removal pattern area. The opening pattern includes only the warp threads or weft threads in the predetermined yarn removal pattern area.

[0007] Furthermore, at the knot, the diameter of the warp threads is reduced to 51%-99% of the original diameter, and the diameter of the weft threads is reduced to 51%-99% of the original diameter.

[0008] Furthermore, the original diameter of the meridian is d1, the thinned diameter of the meridian at the corresponding knot is d1', the original diameter of the parallel is d2, the thinned diameter of the parallel at the corresponding knot is d2', and the angle θ between the meridian and the parallel is 90 + arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees or 90 - arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees.

[0009] Furthermore, the mesh fabric includes a polyester mesh fabric and a metal mesh fabric. The polyester mesh fabric is fixedly connected to the mesh frame and has an opening. The metal mesh fabric is fixedly connected to the polyester mesh fabric and covers the opening on the polyester mesh fabric. The polymer material layer and the predetermined yarn removal pattern area are both disposed on the metal mesh fabric.

[0010] Furthermore, the area of ​​the predetermined yarn removal pattern area is 2-20 times the area of ​​the opening pattern.

[0011] Furthermore, the area of ​​the predetermined yarn removal pattern area is 2-4 times the area of ​​the opening pattern.

[0012] Furthermore, the diameters of the meridians and the parallels are 9μm-16μm and the angle θ between the meridians and the parallels is 100 degrees to 130 degrees.

[0013] The present invention also provides a method for preparing a printing screen, which includes the following steps:

[0014] Step S1: Interweave several parallel warp threads and several parallel weft threads to form a mesh fabric. The original diameter of the warp threads is d1, and the original diameter of the weft threads is d2.

[0015] Step S2: Tighten the mesh fabric so that the warp and weft threads interlock and form a knot between the warp and weft threads;

[0016] Step S3: Etch the mesh knot through an etching process, so that at the mesh knot, the diameter of the warp thread is reduced to d1' and the diameter of the weft thread is reduced to d2';

[0017] Step S4: Rotate the meridian or the parallel to make an angle θ between the meridian and the parallel, wherein the angle θ is 90 + arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees or 90 - arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees;

[0018] Step S5: Stretch and fix the mesh fabric formed in step S4 onto the screen frame to form a semi-finished printing screen.

[0019] Step S6: Apply an emulsion to the mesh fabric of the semi-finished screen to form an emulsion layer, set at least one predetermined yarn removal pattern area on the mesh fabric, and perform an exposure and development process on the mesh fabric within the predetermined yarn removal pattern area.

[0020] Step S7: Remove the warp or weft threads of the mesh fabric within the predetermined yarn removal pattern area by an etching process;

[0021] Step S8: Remove the emulsion layer from the mesh fabric;

[0022] Step S9: Coat the mesh fabric with a polymer material to form a polymer material layer;

[0023] Step S10: At least one opening pattern is formed on the polymer material layer in the area corresponding to the predetermined yarn removal pattern area by an etching process to form a finished printing screen.

[0024] Furthermore, step S1 also includes the following steps:

[0025] Step S11: Interweave several parallel Tedron warp threads and several parallel Tedron weft threads to form a Tedron mesh fabric; interweave several parallel metal warp threads and several parallel metal weft threads to form a metal mesh fabric.

[0026] Step S12: Open an opening in the tertrol mesh, cover the opening with the metal mesh, and press the metal mesh and the tertrol mesh together to form a composite mesh.

[0027] The predetermined yarn removal pattern area, the emulsion layer, and the polymer material layer are all disposed on the metal mesh fabric.

[0028] Furthermore, in step S3, at the knot, the diameter of the warp thread is reduced to 51%-99% of the original diameter, and the diameter of the weft thread is reduced to 51%-99% of the original diameter.

[0029] Furthermore, in step S4, the angle θ between the meridian and the parallel is 100 degrees to 130 degrees.

[0030] Furthermore, in step S10, the area of ​​the predetermined yarn removal pattern area is 2-20 times the area of ​​the opening pattern.

[0031] Furthermore, the area of ​​the predetermined yarn removal pattern area is 2-4 times the area of ​​the opening pattern (131).

[0032] Furthermore, the diameter of the meridian and the diameter of the parallel are 9μm-16μm, respectively.

[0033] The present invention also provides a method for rotating a mesh fabric, the method being used to rotate the warp or weft threads in the screen after the etching process, so that there is an included angle θ between the warp and the weft threads, the included angle θ being 90+arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees or 90-arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees.

[0034] The present invention also provides a rotating device for a mesh fabric, the device being configured to rotate the warp or weft threads in the mesh, such that there is an angle θ between the warp and the weft threads, the angle θ being 90+arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees or 90-arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees.

[0035] Compared with the prior art, this application has at least one or more of the following beneficial effects:

[0036] The printing screen, its manufacturing method, screen rotation method, and equipment disclosed in this application involve thinning the warp and weft threads at the mesh knots. This facilitates the rotation of the warp or weft threads, creating a rotation angle between them so they are no longer perpendicular. This produces a printing screen with a slanted mesh, ensuring that only the warp or weft threads within the opening pattern on the slanted mesh are in a slanted mesh state. Even if the remaining warp or weft threads within the opening pattern have a certain angle with the ink printing direction, this reduces resistance to the ink and improves the accuracy of the printed graphics. The mesh can reduce unevenness and can adapt to various shapes of opening patterns by adjusting the rotation angle between the warp and weft threads; the structural strength of the warp and weft threads can be maintained when the diameter of the refined warp or weft threads is not less than 50% of the original diameter; the mesh count of the warp and weft threads per unit area can be increased when the diameter of the refined warp or weft threads is less than 50% of the original diameter, thus maintaining the tension and structural strength of the mesh; a composite mesh of tertrol mesh and metal mesh can be used, which is more conducive to printing finger electrodes and can further save on the production cost of the screen printing plate. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of a printing screen in the prior art;

[0038] Figure 2 This is a schematic diagram of the structure of the printing screen provided in Embodiment 1 of this application;

[0039] Figure 3 This is an enlarged structural diagram of the original mesh junction provided in Embodiment 1 of this application;

[0040] Figure 4 This is an enlarged structural diagram of the etched and refined mesh junction provided in Embodiment 1 of this application;

[0041] Figure 5 This is a schematic diagram of the structure of the printing screen provided in Embodiment 2 of this application;

[0042] Figure 6 This is a schematic diagram of the structure of the printing screen provided in Embodiment 3 of this application;

[0043] Figure 7 A flowchart illustrating the method for manufacturing a printing screen according to Embodiment 4 of this application;

[0044] Figure 8 This is a schematic diagram of the printing screen structure provided in Embodiment 4 of this application.

[0045] Among them, 1-printing screen, 11-screen frame, 12-mesh fabric, 121-warp, 122-weft, 123-knot, 124-tertrol mesh fabric, 125-metal mesh fabric, 126-composite edge, 13-polymer material layer, 131-opening pattern, 14-emulsion layer, A-predetermined yarn removal pattern area, d1-original warp diameter, d1'-refined warp diameter, d2-original weft diameter, d2'-refined weft diameter, θ-rotation angle, 2-printing screen, 21-screen frame, 22-mesh fabric, 221-warp, 222-weft, 23-polymer material layer, 231-opening pattern. Detailed Implementation

[0046] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description of the specific implementation methods, structure, features and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0047] Example 1

[0048] like Figure 2 As shown, this embodiment provides a printing screen 1, which includes a screen frame 11 and a screen fabric 12 fixed on the screen frame 11. The screen fabric 12 is obtained by interlacing several parallel warp threads 121 and several parallel weft threads 122. A knot 123 is formed at the intersection of any warp thread 121 and all weft threads 122, thus forming several knots 123 on the screen fabric 12. One side of the screen fabric 12 serves as the squeegee surface, and the other side serves as the printing surface. The original diameter of the warp thread 121 is defined as d1, and the original diameter of the weft thread 122 is defined as d2, as follows... Figure 3 As shown. The mesh 123 is etched using an etching process, causing the diameter of the warp threads 121 at the mesh 123 to become thinner. The thinned diameter of the warp threads 121 is defined as d1', and the diameter of the weft threads 122 is also thinned. The thinned diameter of the weft threads 122 is defined as d2'. Figure 4 As shown. It is important to know that... Figure 4 The positional relationship of the warp 121 and the weft 122 at the refined knot 123 shown is only for illustrative purposes. When the warp 121 and the weft 122 are rotated relative to each other as described below, they can also be tightly engaged together.

[0049] The printing screen 1 of this application can be applied to fine-diameter screens, that is, the diameter of the warp 121 and the weft 122 can be 9μm-16μm, in order to accommodate the production of more delicate patterns.

[0050] In this embodiment, the refined diameter of the warp 121 and the weft 122 is preferably not less than 50% of the original diameter to maintain the structural strength of the warp 121 or the weft 122. For example, the refined diameter d1' of the warp 121 is 51-99% of the original diameter d1 of the warp 121, and the refined diameter d2' of the weft 122 is 51-99% of the original diameter d2 of the weft 122. It should be noted that the above is only a preferred embodiment. If the refined diameter of the warp 121 and the weft 122 is less than 50% of the original diameter, the mesh count of the warp 121 and the weft 122 per unit area of ​​the mesh fabric 12 can be changed, for example, increased to 360-380 mesh or 380-500 mesh, to maintain the tension and structural strength of the mesh fabric 12.

[0051] The warp threads 121 and the weft threads 122 are not perpendicular to each other. That is, the warp threads 121 and weft threads 122, which are perpendicular to each other after weaving, are rotated relative to each other by a set angle θ1, so that an angle θ is formed between the warp threads 121 and the weft threads 122. Figure 2 As shown. The included angle θ is determined by the diameters d1 and d1' of meridian 121 and the diameters d2 and d2' of parallel 122. The included angle θ is 90 + arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees or 90 - arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees. Since there are two included angles between the meridians and parallels, one acute and one obtuse, the ± sign is used in the above formula to represent either of the two included angles between the meridians and parallels.

[0052] In other words, in this embodiment, the warp 121 and weft 122 at the mesh knot 123 are etched and refined, making the warp 121 and weft 122 more sparse at the mesh knot 123. This facilitates the subsequent relative rotation between the warp 121 and weft 122, thereby preventing the warp 121 and weft 122 from being perpendicular. The rotation angle θ1 between the warp 121 and weft 122 is determined based on the difference between the refined wire diameter and the original wire diameter of the warp 121 and weft 122, which is d1-d1' and d2-d2'. The formula for calculating the rotation angle is arctan{((d1-d1'+d2-d2') / 2) / d1'}. The following table lists the rotation angle values ​​corresponding to several wire diameter differences between 2μm and 9μm, as shown in Table 1 below:

[0053]

[0054]

[0055] Table 1

[0056] As shown in Table 1, the rotation angle θ1 can be any angle within the range of 10 degrees to 40 degrees. Therefore, the rotation angle θ1 between the meridian 121 and the parallel 122 is preferably between 10 degrees and 40 degrees, that is, the included angle θ between the meridian 121 and the parallel 122 is preferably between 100 degrees and 130 degrees.

[0057] The mesh fabric 12 has at least one predetermined yarn removal pattern area A, which contains only warp threads 121 or weft threads 122. The mesh fabric 12 is covered with a polymer material layer 13. At least one opening pattern 131 is provided on the polymer material layer 13 corresponding to the predetermined yarn removal pattern area A. It should be noted that the opening pattern 131 can be located anywhere within the area corresponding to the predetermined yarn removal pattern area A, for example, it can be at the center of the area, or at other non-central locations. Since the predetermined yarn removal pattern area A contains only warp threads 121 or weft threads 122, the corresponding opening pattern 131 also contains only warp threads 121 or weft threads 122. Figure 2 As shown in the figure, this is only a schematic illustration of a printing screen 1 structure that includes only the weft yarn 122. Preferably, the area of ​​the predetermined yarn removal pattern area A is 2-20 times the area of ​​the opening pattern 131, more preferably 2-4 times, to facilitate the formation of the opening pattern 131. Furthermore, in this embodiment, the warp yarn 121 or the weft yarn 122 can be made of metal, such as stainless steel or tungsten carbide. It should be noted that... Figure 2 The L-shaped opening pattern 131 shown is only an adjustment of the setting position for the convenience of illustration. In actual implementation, the opening pattern 131 can be located at the center of the corresponding predetermined yarn removal pattern area A or other positions.

[0058] Therefore, although in this embodiment, the opening pattern 131 also includes only warp threads 121 or weft threads 122, because the warp threads 121 or weft threads 122 in the opening pattern 131 are in a diagonal mesh state, forming a certain angle with the printing direction of the ink, the resistance of the warp threads 121 or weft threads 122 to the ink is small during printing, and the printed pattern is more accurate and has less undulation. In particular, the technical solution of this embodiment can be applied to opening patterns 131 of various shapes.

[0059] Example 2

[0060] like Figure 5As shown, in this embodiment, the warp 121 is woven parallel to the Y-axis in space, while the weft 122 is woven at an angle. Similar to Embodiment 1, at the knots 123 formed by the interlacing of the warp 121 and weft 122, each warp 121 and each weft 122 is also thinned, and there is an angle θ between the warp 121 and the weft 122. Figure 5 The opening pattern 131 shown has several spaced strip rectangles, and the length direction of the opening pattern 131 is consistent with the direction of the warp 121. Therefore, the weft 122 in the opening pattern 131 is inclined, which is more conducive to printing finger electrodes.

[0061] Example 3

[0062] This embodiment differs from the other two embodiments one and two in that the mesh fabric 12 is a composite mesh fabric. For example... Figure 6 As shown, the mesh fabric 12 includes a polyester mesh fabric 124 and a metal mesh fabric 125. The polyester mesh fabric 124 is fixedly connected to the mesh frame 11. The polyester mesh fabric 124 has an opening, and the metal mesh fabric 125 is fixedly connected to it, covering the opening on the polyester mesh fabric 124. Therefore, a composite edge 126 is formed between the polyester mesh fabric 124 and the metal mesh fabric 125. The polymer material layer 13 and the predetermined yarn removal pattern area A are both disposed on the metal mesh fabric 125. The structure of the metal mesh fabric 125 is the same as that of the mesh fabric 12 in Embodiment 2. Using this composite mesh fabric and the opening pattern 131 is more conducive to printing finger electrodes while further saving the production cost of the printing screen 1.

[0063] Example 4

[0064] This embodiment provides a method for producing a printing screen, such as... Figure 7 As shown, the specific steps are as follows:

[0065] Step S1: Several parallel warp threads 121 and several parallel weft threads 122 are interwoven in an alternating manner to form a mesh 12, wherein the diameter of the warp thread 121 is d1, that is, the original diameter of the warp thread 121, and the diameter of the weft thread 122 is d2, that is, the original diameter of the weft thread 122.

[0066] Step S2: Tighten the mesh fabric 12 so that the warp threads 121 and the weft threads 122 interlock with each other, and form a knot 123 between the warp threads 121 and the weft threads 122;

[0067] Step S3: The mesh knot 123 is etched by an etching process, so that the diameter of the warp 121 corresponding to the position of the mesh knot 123 is reduced to d1', and the diameter of the weft 122 corresponding to the position of the mesh knot 123 is reduced to d2'.

[0068] Step S4: Use a rotating device to rotate the warp 121 or the weft 122. That is, keep the direction of the warp 121 stationary and move the two ends of the mesh fabric 12 in the direction of the weft 122 in a staggered manner in the direction of the warp 121; or keep the direction of the weft 122 stationary and move the two ends of the mesh fabric 12 in the direction of the warp 121 in a staggered manner in the direction of the weft 122, so that there is an angle θ between the warp 121 and the weft 122. The angle θ is 90 + arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees or 90 - arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees. That is, the rotation angle θ1 between the warp 121 and the weft 122 is arctan{((d1-d1'+d2-d2') / 2) / d1'} degrees.

[0069] Step S5: Stretch and fix the mesh fabric 12 formed in step S4 onto the mesh frame 11 to form a semi-finished printing screen.

[0070] Step S6: Apply an emulsion to the mesh fabric 12 of the semi-finished screen to form an emulsion layer 14, set at least one predetermined yarn removal pattern area A on the mesh fabric 12, and perform an exposure and development process on the mesh fabric 12 in the predetermined yarn removal pattern area A.

[0071] Step S7: Remove the warp threads 121 or weft threads 122 of the mesh fabric 12 within the predetermined yarn removal pattern area A using an etching process. The structure after removal is as follows: Figure 8 As shown;

[0072] Step S8: Remove the emulsion layer 14 from the mesh fabric 12;

[0073] Step S9: Coat the mesh 12 with a polymer material to form a polymer material layer 13;

[0074] Step S10: At least one opening pattern 131 is formed on the polymer material layer 13 in the area corresponding to the predetermined yarn removal pattern area A by an etching process, forming a finished printing screen.

[0075] Preferably, in step S1, the original diameters d1 and d2 of the warp 121 and weft 122 can be any value within the range of 9μm-16μm. In step S3, at the knot, the diameter of the warp is reduced to 51%-99% of its original diameter, and the diameter of the weft is reduced to 51%-99% of its original diameter. In step S4, the angle θ between the warp 121 and the weft 122 is 100 degrees to 130 degrees, that is, the rotation angle θ1 between the warp 121 and the weft 122 is 10 degrees to 40 degrees. In step S10, the area of ​​the predetermined yarn removal pattern area A is 2-20 times the area of ​​the opening pattern 131, more preferably 2-4 times. The etching process in steps S7 and S10 can be dry etching, such as laser etching, or wet etching, such as acid / alkali solution etching.

[0076] In another embodiment, the mesh fabric 12 can also be as follows: Figure 6 The composite mesh fabric shown above, corresponding to step S1, also includes the following steps:

[0077] Step S11: Interweave several parallel Tedron warp threads and several parallel Tedron weft threads to form a Tedron mesh 124, and interweave several parallel metal warp threads and several parallel metal weft threads to form a metal mesh 125.

[0078] Step S12: An opening is made in the tertrol mesh 124, the metal mesh 125 is covered in the opening, and the metal mesh 125 and the tertrol mesh 124 are pressed together to form a composite mesh. In subsequent process steps, the predetermined yarn removal pattern area A, the emulsion layer 14, and the polymer material layer 13 are all disposed on the metal mesh 125.

[0079] As can be seen from the above content of this application, this application refines the warp and weft threads at the mesh knots by etching, facilitating relative rotation between the warp and weft threads to create a rotation angle, thereby producing a printing screen with a slanted mesh. An opening pattern can also be formed on the slanted printing screen, and the rotation angle can be adjusted according to actual needs. This application includes only warp or weft threads in the opening pattern, and because the warp or weft threads in the opening pattern are in a slanted mesh state, there is less resistance to ink during printing, resulting in more accurate graphics with less unevenness, lower impedance, and higher power generation efficiency. Furthermore, the printing screen, by adjusting the rotation angle between the warp and weft threads, can be applied to opening patterns of various shapes. Moreover, the printing screen of this application is suitable for fine-diameter screens, such as those with a diameter of 9-16μm, to accommodate more intricate pattern production. Therefore, the technical solution of this application is applicable to the printing screen industry.

[0080] In this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0081] In this document, the directional terms such as front, back, top, and bottom are defined based on the location of the components in the accompanying drawings and their relative positions to each other, solely for the purpose of clarity and convenience in expressing the technical solution. It should be understood that the use of these directional terms should not limit the scope of protection claimed in this application.

[0082] Where there is no conflict, the above embodiments and features described herein can be combined with each other.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A printing screen, characterized in that, It includes a frame (11) and a mesh fabric (12) fixed on the frame (11). The mesh fabric (12) includes several parallel warp threads (121) and several parallel weft threads (122). The warp threads (121) and the weft threads (122) interweave to form several knots (123). At the knots (123), the diameter of the warp threads (121) and the diameter of the weft threads (122) decrease. 22) are not perpendicular to each other. The mesh fabric (12) is provided with at least one predetermined yarn removal pattern area. The predetermined yarn removal pattern area includes only warp (121) or weft (122). The mesh fabric (12) is covered with a polymer material layer (13). The polymer material layer (13) is provided with at least one opening pattern (131) in the area corresponding to the predetermined yarn removal pattern area. The opening pattern (131) includes only warp (121) or weft (122) in the predetermined yarn removal pattern area. At the knot, the diameter of the warp (121) is reduced to 51%-99% of its original diameter, and the diameter of the weft (122) is reduced to 51%-99% of its original diameter. The original diameter of the meridian (121) is d1, and the thinned diameter of the meridian (121) at the corresponding knot (123) is d1'. The original diameter of the parallel (122) is d2, and the thinned diameter of the parallel (122) at the corresponding knot (123) is d2'. The angle θ between the meridian (121) and the parallel (122) is 90 + arctan{(d1-d1'+d2-d2') / 2) / d1'} degrees or 90-arctan{ ((d1-d1'+d2-d2') / 2) / d1'} degrees.

2. The printing screen according to claim 1, characterized in that, The mesh fabric (12) includes a polyester mesh fabric (124) and a metal mesh fabric (125). The polyester mesh fabric (124) is fixedly connected to the mesh frame (11). An opening is provided on the polyester mesh fabric (124). The metal mesh fabric (125) is fixedly connected to the polyester mesh fabric (124). The metal mesh fabric (125) covers the opening on the polyester mesh fabric (124). The polymer material layer (13) and the predetermined yarn removal pattern area are both disposed on the metal mesh fabric (125).

3. The printing screen according to claim 1, characterized in that, The area of ​​the predetermined yarn removal pattern area is 2-20 times the area of ​​the opening pattern (131).

4. The printing screen according to claim 1, characterized in that, The area of ​​the predetermined yarn removal pattern area is 2-4 times the area of ​​the opening pattern (131).

5. The printing screen according to claim 1, characterized in that, The diameter of the meridian (121) and the diameter of the parallel (122) are 9µm-16µm respectively; The angle θ between the meridian (121) and the parallel (122) is 100 to 130 degrees.

6. A method for preparing a printing screen, characterized in that, The preparation method is used to prepare the printing screen as described in any one of claims 1-5, and includes the following steps: Step S1: Interweave several parallel warp threads (121) and several parallel weft threads (122) to form a mesh (12), wherein the original diameter of the warp threads (121) is d1 and the original diameter of the weft threads (122) is d2. Step S2: Tighten the net fabric (12) so that the warp threads (121) and the weft threads (122) interlock and form a knot (123) between the warp threads (121) and the weft threads (122). Step S3: Etch the mesh knot (123) through an etching process, so that at the mesh knot (123), the diameter of the warp (121) is reduced to d1' and the diameter of the weft (122) is reduced to d2'. Step S4: Rotate the meridian (121) or the parallel (122) so that there is an angle θ between the meridian (121) and the parallel (122), wherein the angle θ is... 90 + arctan{ ((d1-d1'+d2-d2') / 2) / d1'} degrees or 90-arctan{ ((d1-d1'+d2-d2') / 2) / d1'} degrees; Step S5: Stretch and fix the mesh fabric (12) formed in step S4 onto the mesh frame (11) to form a semi-finished printing screen; Step S6: Apply an emulsion to the mesh fabric (12) of the semi-finished screen to form an emulsion layer (14), set at least one predetermined yarn removal pattern area on the mesh fabric (12), and perform an exposure and development process on the mesh fabric (12) in the predetermined yarn removal pattern area. Step S7: Remove the warp (121) or weft (122) of the mesh fabric (12) within the predetermined yarn removal pattern area by an etching process; Step S8: Remove the emulsion layer (14) on the mesh fabric (12); Step S9: Coat the mesh (12) with a polymer material to form a polymer material layer (13); Step S10: At least one opening pattern (131) is formed in the region corresponding to the predetermined yarn removal pattern area on the polymer material layer (13) by an etching process to form a finished printing screen.

7. The method for preparing a printing screen according to claim 6, characterized in that, Step S1 also includes the following steps: Step S11: Interweave several parallel Tedron warp threads and several parallel Tedron weft threads to form a Tedron mesh (124), and interweave several parallel metal warp threads and several parallel metal weft threads to form a metal mesh (125). Step S12: Open an opening in the tertrol mesh (124), cover the opening with the metal mesh (125), and press the metal mesh (125) and the tertrol mesh (124) together to form a composite mesh. The predetermined yarn removal pattern area, the emulsion layer (14), and the polymer material layer (13) are all disposed on the metal mesh fabric (125).

8. The method for preparing a printing screen according to claim 6, characterized in that, In step S3, at the knot, the diameter of the warp (121) is reduced to 51%-99% of the original diameter, and the diameter of the weft (122) is reduced to 51%-99% of the original diameter.

9. The method for preparing a printing screen according to claim 6, characterized in that, In step S4, the angle θ between the meridian (121) and the parallel (122) is 100 to 130 degrees.

10. The method for preparing a printing screen according to claim 6, characterized in that, In step S10, the area of ​​the predetermined yarn removal pattern area is 2-20 times the area of ​​the opening pattern (131).

11. The method for preparing a printing screen according to claim 10, characterized in that, The area of ​​the predetermined yarn removal pattern area is 2-4 times the area of ​​the opening pattern (131).

12. The method for preparing a printing screen according to claim 6, characterized in that, The diameter of the meridian (121) and the diameter of the parallel (122) are 9µm-16µm, respectively.

13. A method for rotating a mesh fabric, characterized in that, The method is used to rotate the mesh fabric according to any one of claims 1-5. The method is used to rotate the warp (121) or weft (122) in the screen after the etching process, so that there is an angle θ between the warp (121) and the weft (122), wherein the angle θ is 90 + arctan{(d1-d1'+d2-d2') / 2) / d1'} degrees or 90-arctan{ ((d1-d1'+d2-d2') / 2) / d1'} degrees.

14. A rotating device for a mesh fabric, characterized in that, The rotating device is applied to the mesh fabric according to any one of claims 1-5, the device being configured to rotate the warp (121) or weft (122) in the mesh, such that there is an included angle θ between the warp (121) and the weft (122), the included angle θ being 90 + arctan{(d1-d1'+d2-d2') / 2) / d1'} degrees or 90-arctan{ ((d1-d1'+d2-d2') / 2) / d1'} degrees.

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