Metal screen plate for improving height-width ratio of printing paste

Abstract

The utility model provides a metal screen capable of improving the height-width ratio of printing paste, which is provided with at least two metal thin layers in a laminated manner, each metal thin layer is uniformly provided with a plurality of printing grooves, and the positions of the printing grooves of each metal thin layer correspond to each other. The opening area of the printing groove of the scraper face is larger than that of the printing groove of the printing face, and a first ink storage groove is formed in the outer edge of the metal thin layer printing groove in the scraper face. By means of the mode, the problems that in the printing process of an existing metal screen, slurry is prone to drying, so that fluidity is poor, the printing height-width ratio is low, inking is uneven, and virtual printing is prone to occurring are solved.

Description

Technical Field

[0001] The utility model relates to the field of photovoltaic cell printing, in particular to a metal screen capable of improving the aspect ratio of printing slurry. Background Art

[0002] The silicon substrates in the photovoltaic cells are connected by metal wires. The metal wires are printed on the surface of the silicon substrate with metal slurry through the screen printing process. Specifically, a scraper is used to pass the metal slurry through the printing holes on the surface of the metal screen and print it on the surface of the silicon substrate, eventually forming metal grid lines.

[0003] In actual production, due to the small opening area of ​​the printing hole, the slurry is easy to dry, resulting in poor fluidity, low printing aspect ratio, uneven ink placement, easy to print falsely, etc. As a result, the entire produced cell has a large shading area, small short-circuit current, large open-circuit voltage, and low light efficiency. Utility Model Content

[0004] To solve the above problems, the utility model proposes a metal screen that improves the aspect ratio of printing slurry, which solves the problems of easy drying of slurry during existing metal screen printing, resulting in poor fluidity, low printing aspect ratio, uneven ink application, and easy false printing.

[0005] The main contents of the utility model include: a metal screen for improving the aspect ratio of printing slurry, the metal screen is stacked with at least two metal thin layers, each metal thin layer is evenly provided with a plurality of printing grooves, and the positions of the printing grooves of each metal thin layer are arranged correspondingly, the opening area of ​​the printing grooves on the scraper surface is larger than the opening area of ​​the printing grooves on the printing surface, and a first ink storage groove is provided at the outer edge of the metal thin layer printing groove on the scraper surface.

[0006] Preferably, both ends of the first ink storage tank are arranged as arc-shaped structures protruding outward.

[0007] Preferably, the width W1 of the arc-shaped structure is in the range of 6-100 μm, and the depth H1 is in the range of 1-50 μm.

[0008] Preferably, at least one inwardly protruding boss is provided along both side edges of the first ink storage tank.

[0009] Preferably, the boss is disposed perpendicularly to the end surface of the metal mesh, or is disposed obliquely to the end surface of the metal mesh.

[0010] Preferably, the height of the boss is flush with the end surface of the metal mesh or is arranged beyond the end surface of the metal mesh.

[0011] Preferably, the width W2 of the boss is in the range of 4-50 μm, and the height H2 is in the range of 1-50 μm.

[0012] Preferably, a plurality of second ink storage grooves are provided on the upper surface of the metal screen scraper surface.

[0013] Preferably, the structure of the second ink storage tank is configured such that the shape is configured as a combination of one or more of a circle, a rectangle, a diamond, a trapezoid, a triangle, and a polygon.

[0014] Preferably, the width W3 of the printing holes formed on the printing surface is in the range of 1-40 μm.

[0015] Preferably, the angle α between the center line of the boss and the center line of the printing hole provided on the printing surface is in the range of 5-90°.

[0016] The beneficial effects of the utility model are:

[0017] 1. By adding a first ink storage tank on the surface of the metal screen on the scraper surface, the metal slurry can be scraped into the surface of the silicon substrate more easily, the aspect ratio of the metal slurry is improved, and the ink is applied to the battery cell more evenly;

[0018] 2. Both ends of the first ink storage tank are configured as arc-shaped structures protruding outward, which increases the ink storage capacity, and the ink storage tank with the arc-shaped structure is not easy to have residue after use.

[0019] 3. A number of second ink storage grooves are provided on the upper surface of the metal screen scraper surface to ensure the wettability of the slurry on the scraper surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of a first metal screen;

[0021] Figure 2 is a schematic structural diagram of a second metal screen;

[0022] Figure 3 This is a schematic diagram of the structure when the first metal screen and the second metal screen are superimposed in Example 1;

[0023] Figure 4 for Figure 3 A partial enlarged schematic diagram of part B in the middle;

[0024] Figure 5 for Figure 3 Schematic diagram of the middle AA section;

[0025] Figure 6 It is a structural schematic diagram of Example 2;

[0026] Figure 7 It is a structural schematic diagram of Example 3;

[0027] Figure 8 It is a structural schematic diagram of Example 4;

[0028] Reference numerals:

[0029] 1. a first metal thin layer, 11. a first printing groove;

[0030] 2. second metal thin layer, 21. first ink storage tank, 22. second ink storage tank, 211. arc-shaped structure, 212. boss. DETAILED DESCRIPTION

[0031] The technical solution protected by the utility model is described in detail below with reference to the accompanying drawings.

[0032] Example 1

[0033] like Figure 1-3 As shown, a metal screen for improving the aspect ratio of printing paste comprises: at least two metal screens arranged in a stacked manner. In this embodiment, two metal thin layers are used, and each metal thin layer is evenly provided with a plurality of printing grooves, such as Figure 1 The first printing slot 11 and Figure 2 The first ink storage tank 21 in the embodiment is a printing tank for metal slurry. The position of each metal thin layer printing tank is correspondingly arranged (such as Figure 3 As shown in the figure, the opening area of ​​the printing groove on the scraper surface is larger than the opening area of ​​the printing groove on the printing surface. A first ink storage groove 21 is provided at the outer edge of the metal thin layer printing groove on the scraper surface. In this embodiment, the first ink storage groove 21 is the printing groove of the second metal thin layer 2, and its opening size is larger than the first printing groove 11 of the first metal thin layer 1 on the printing surface. When printing, the metal slurry first enters the first ink storage groove 21, then enters the first printing groove 11, and finally reaches the surface of the photovoltaic cell to form a metal grid line.

[0034] like Figure 4 As shown, in order to prevent the metal slurry from drying out and causing poor fluidity during the printing process, and being directly scraped away by the scraper without entering the surface of the silicon substrate, the two ends of the first ink storage tank 21 are set as arc-shaped structures 211 protruding outward. The width W1 of the arc-shaped structure 211 ranges from 6 to 100 μm, and the depth H1 ranges from 1 to 50 μm. Since the opening area of ​​the first ink storage tank 21 is relatively larger than the opening area of ​​the first printing tank 11, the metal slurry is more likely to enter the first ink storage tank 21 and be stored therein. When the metal slurry is hung here by the scraper again, the metal slurry is more likely to combine with the metal slurry in the first ink storage tank 21, and finally it is easier to be scraped into the surface of the silicon substrate. The transmittance of the metal slurry is improved, the aspect ratio of the slurry printing is improved, and the metal grid lines on the battery cell are more uniform.

[0035] like Figure 4 , Figure 5As shown, at least one boss 212 protruding inward is provided along both sides of the first ink storage tank 21. The width W2 of the boss 212 is in the range of 4-50 μm, and the height H2 is in the range of 1-50 μm. The design of the boss 212 can increase the strength of the second metal thin layer 2, and at the same time, it is more conducive to the slurry falling into the first metal thin layer printing hole 11. In this embodiment, the boss 212 is arranged perpendicular to the end face of the second metal thin layer 2, and the height of the boss 212 is flush with the end face of the second metal thin layer 2.

[0036] Furthermore, in order to further increase the utilization rate of the metal slurry of the entire second metal thin layer 2 and ensure the wettability of the slurry during printing, a plurality of second ink storage grooves 22 are provided on the upper surface of the second metal thin layer 2. The structure of the second ink storage grooves 22 is set to be a combination of one or more of a circle, a rectangle, a diamond, a trapezoid, a triangle, and a polygon. In this embodiment, the second ink storage groove 22 is provided as a circular structure.

[0037] Furthermore, the width W3 of the printing hole of the printing surface is in the range of 1-40 μm, which is convenient for blanking and printing of metal paste.

[0038] Example 2

[0039] like Figure 1-4 As shown, a metal screen for improving the aspect ratio of printing paste comprises: at least two metal thin layers stacked in layers. In this embodiment, two metal thin layers are used, and each metal thin layer is evenly provided with a plurality of printing grooves, such as Figure 1 The first printing slot 11 and Figure 2 The first ink storage tank 21 in the embodiment is a printing tank for metal slurry. The position of each metal thin layer printing tank is correspondingly arranged (such as Figure 3 As shown in the figure, the opening area of ​​the printing groove on the scraper surface is larger than the opening area of ​​the printing groove on the printing surface. A first ink storage groove 21 is provided at the outer edge of the printing groove of the metal thin layer on the scraper surface. In this embodiment, the first ink storage groove 21 is the printing groove of the second metal thin layer 2, and its opening size is larger than the first printing groove 11 of the first metal thin layer 1 on the printing surface. When printing, the metal slurry first enters the first ink storage groove 21, then enters the first printing groove 11, and finally reaches the surface of the photovoltaic cell to form a metal grid line.

[0040] like Figure 4As shown, in order to prevent the metal slurry from drying out and causing poor fluidity during the printing process, and being directly scraped away by the scraper without entering the surface of the silicon substrate, the two ends of the first ink storage tank 21 are set as arc-shaped structures 211 protruding outward. The width W1 of the arc-shaped structure 211 ranges from 6 to 100 μm, and the depth H1 ranges from 1 to 50 μm. Since the opening area of ​​the first ink storage tank 21 is relatively larger than the opening area of ​​the first printing tank 11, the metal slurry is more likely to enter the first ink storage tank 21 and be stored therein. When the metal slurry is hung here by the scraper again, the metal slurry is more likely to combine with the metal slurry in the first ink storage tank 21, and finally it is easier to be scraped into the surface of the silicon substrate. The transmittance of the metal slurry is improved, the aspect ratio of the slurry printing is improved, and the metal grid lines on the battery cell are more uniform.

[0041] like Figure 4 , Figure 6 As shown, at least one inwardly protruding boss 212 is provided along both side edges of the first ink storage tank 21. The width W2 of the boss 212 is in the range of 4-50μm, and the height H2 is in the range of 1-50μm. Through the design of the boss 212, it is possible to increase the strength of the second metal thin layer 2, and at the same time, it is more conducive to the slurry falling into the first metal thin layer printing hole 11. In this embodiment, the boss 212 is inclined between the end surface of the second metal thin layer 2, and the height of the boss 212 is flush with the end surface of the second metal thin layer 2. In this embodiment, the boss 212 is inclined between the end surface of the second metal thin layer 2, and the structure with a wide lower part and a narrow upper part can increase the overall strength of the boss 212.

[0042] Furthermore, in order to further increase the utilization rate of the metal slurry of the entire second metal thin layer 2 and ensure the wettability of the slurry during printing, a plurality of second ink storage grooves 22 are provided on the upper surface of the second metal thin layer 2. The structure of the second ink storage grooves 22 is set to be a combination of one or more of a circle, a rectangle, a diamond, a trapezoid, a triangle, and a polygon. In this embodiment, the second ink storage groove 22 is provided as a circular structure.

[0043] Furthermore, the width W3 of the bottom printing hole is in the range of 1-40 μm, which is convenient for the blanking and printing of the metal paste.

[0044] Example 3

[0045] like Figure 1-4 As shown, a metal screen for improving the aspect ratio of printing paste comprises: at least two metal thin layers stacked in layers. In this embodiment, two metal thin layers are used, and each metal thin layer is evenly provided with a plurality of printing grooves, such as Figure 1 The first printing slot 11 and Figure 2 The first ink storage tank 21 in the embodiment is a printing tank for metal slurry. The position of each metal thin layer printing tank is correspondingly arranged (such as Figure 3As shown in the figure, the opening area of ​​the printing groove on the scraper surface is larger than the opening area of ​​the printing groove on the printing surface. A first ink storage groove 21 is provided at the outer edge of the metal thin layer printing groove on the scraper surface. In this embodiment, the first ink storage groove 21 is the printing groove of the second metal thin layer 2, and its opening size is larger than the first printing groove 11 of the first metal thin layer 1 on the printing surface. When printing, the metal slurry first enters the first ink storage groove 21, then enters the first printing groove 11, and finally reaches the surface of the photovoltaic cell to form a metal grid line.

[0046] like Figure 4 As shown, in order to prevent the metal slurry from drying out and causing poor fluidity during the printing process, and being directly scraped away by the scraper without entering the surface of the silicon substrate, the two ends of the first ink storage tank 21 are set as arc-shaped structures 211 protruding outward. The width W1 of the arc-shaped structure 211 ranges from 6 to 100 μm, and the depth H1 ranges from 1 to 50 μm. Since the opening area of ​​the first ink storage tank 21 is relatively larger than the opening area of ​​the first printing tank 11, the metal slurry is more likely to enter the first ink storage tank 21 and be stored therein. When the metal slurry is hung here by the scraper again, the metal slurry is more likely to combine with the metal slurry in the first ink storage tank 21, and finally it is easier to be scraped into the surface of the silicon substrate. The transmittance of the metal slurry is improved, the aspect ratio of the slurry printing is improved, and the metal grid lines on the battery cell are more uniform.

[0047] like Figure 4 , Figure 6 As shown, at least one boss 212 protruding inward is provided along both side edges of the first ink storage tank 21. The width W2 of the boss 212 is in the range of 4-50μm, and the height H2 is in the range of 1-50μm. The design of the boss 212 can increase the strength of the second metal thin layer 2. In this embodiment, the boss 212 is arranged perpendicular to the end face of the second metal thin layer 2, and the height of the boss 212 exceeds the end face of the second metal thin layer 2. The protruding part of the boss 212 is slightly higher than the upper surface of the second metal thin layer 2, which can form a certain blocking effect on the metal slurry, preventing the metal slurry from being directly scraped away by the scraper during printing. Through the blocking of the boss 212, the metal slurry can more easily enter the first ink storage tank 21.

[0048] Furthermore, in order to further increase the utilization rate of the metal slurry of the entire second metal thin layer 2 and ensure the wettability of the slurry during printing, a plurality of second ink storage grooves 22 are provided on the upper surface of the second metal thin layer 2. The structure of the second ink storage grooves 22 is set to be a combination of one or more of a circle, a rectangle, a diamond, a trapezoid, a triangle, and a polygon. In this embodiment, the second ink storage groove 22 is provided as a circular structure.

[0049] Furthermore, the width W3 of the printing hole of the printing surface is in the range of 1-40 μm, which is convenient for blanking and printing of metal paste.

[0050] Example 4

[0051] like Figure 1-4 As shown, a metal screen for improving the aspect ratio of printing paste comprises: at least two metal thin layers stacked in layers. In this embodiment, two metal thin layers are used, and each metal thin layer is evenly provided with a plurality of printing grooves, such as Figure 1 The first printing slot 11 and Figure 2 The first ink storage tank 21 in the embodiment is a printing tank for metal slurry. The position of each metal thin layer printing tank is correspondingly arranged (such as Figure 3 As shown in the figure, the opening area of ​​the printing groove on the scraper surface is larger than the opening area of ​​the printing groove on the printing surface. A first ink storage groove 21 is provided at the outer edge of the printing groove of the metal thin layer on the scraper surface. In this embodiment, the first ink storage groove 21 is the printing groove of the second metal thin layer 2, and its opening size is larger than the first printing groove 11 of the first metal thin layer 1 on the printing surface. When printing, the metal slurry first enters the first ink storage groove 21, then enters the first printing groove 11, and finally reaches the surface of the photovoltaic cell to form a metal grid line.

[0052] like Figure 4 As shown, in order to prevent the metal slurry from drying out and causing poor fluidity during the printing process, and being directly scraped away by the scraper without entering the surface of the silicon substrate, the two ends of the first ink storage tank 21 are set as arc-shaped structures 211 protruding outward. The width W1 of the arc-shaped structure 211 ranges from 6 to 100 μm, and the depth H1 ranges from 1 to 50 μm. Since the opening area of ​​the first ink storage tank 21 is relatively larger than the opening area of ​​the first printing tank 11, the metal slurry is more likely to enter the first ink storage tank 21 and be stored therein. When the metal slurry is hung here by the scraper again, the metal slurry is more likely to combine with the metal slurry in the first ink storage tank 21, and finally it is easier to be scraped into the surface of the silicon substrate. The transmittance of the metal slurry is improved, the aspect ratio of the slurry printing is improved, and the metal grid lines on the battery cell are more uniform.

[0053] like Figure 8 As shown, at least one boss 212 is provided along both sides of the first ink storage tank 21. The width W2 of the boss 212 is in the range of 4-50 μm, and the height H2 is in the range of 1-50 μm. The design of the boss 212 can increase the strength of the second metal thin layer 2. Figure 8 As shown in a, the angle α between the center line of the boss 212 and the center line of the printing hole on the printing surface is in the range of 5-90°, preferably 22.5°. This angle design is also more conducive to the slurry falling into the first metal thin layer printing hole 11. Figure 8As shown in FIG. 8b and FIG. 8c, a gap may be left between the boss 212 and the first metal thin layer printing hole 11, or the edge of the boss 212 may be in an arc shape, so as to facilitate the slurry to fall into the first metal thin layer printing hole 11. In this embodiment, the boss 212 is arranged obliquely to the end surface of the second metal thin layer 2, and the height of the boss 212 is flush with the end surface of the second metal thin layer 2. In this embodiment, the boss 212 is arranged obliquely to the end surface of the second metal thin layer 2, and the structure of the lower part being wide and the upper part being narrow can increase the overall strength of the boss 212.

[0054] Furthermore, in order to further increase the utilization rate of the metal slurry of the entire second metal thin layer 2 and ensure the wettability of the slurry during printing, a plurality of second ink storage grooves 22 are provided on the upper surface of the second metal thin layer 2. The structure of the second ink storage grooves 22 is set to be a combination of one or more of a circle, a rectangle, a diamond, a trapezoid, a triangle, and a polygon. In this embodiment, the second ink storage groove 22 is provided as a circular structure.

[0055] Furthermore, the width W3 of the bottom printing hole is in the range of 1-40 μm, which is convenient for the blanking and printing of the metal paste.

[0056] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A metal screen for improving the aspect ratio of printing paste, characterized in that: The metal screen stack is provided with at least two metal thin layers, each metal thin layer is evenly provided with a plurality of printing grooves, and the positions of the printing grooves of each metal thin layer are arranged correspondingly, the opening area of ​​the printing grooves on the scraper surface is larger than the opening area of ​​the printing grooves on the printing surface, and a first ink storage groove is provided at the outer edge of the metal thin layer printing grooves on the scraper surface.

2. A metal screen for improving the aspect ratio of printing paste according to claim 1, characterized in that: Both ends of the first ink storage tank are configured as arc-shaped structures protruding outward.

3. A metal screen for improving the aspect ratio of printing paste according to claim 2, characterized in that: The arc-shaped structure has a width W1 ranging from 6 to 100 μm, and a depth H1 ranging from 1 to 50 μm.

4. The metal screen for improving the aspect ratio of printing paste according to claim 1, characterized in that: At least one inwardly protruding boss is arranged along both side edges of the first ink storage groove.

5. The metal screen for improving the aspect ratio of printing paste according to claim 4, characterized in that: The boss is arranged perpendicular to the end surface of the metal screen, or is arranged obliquely to the end surface of the metal screen.

6. A metal screen for improving the aspect ratio of printing paste according to claim 4 or 5, characterized in that: The height of the boss is flush with the end surface of the metal screen or is arranged beyond the end surface of the metal screen.

7. A metal screen for improving the aspect ratio of printing paste according to claim 6, characterized in that: The width W2 of the boss is in the range of 4-50 μm, and the height H2 is in the range of 1-50 μm.

8. The metal screen for improving the aspect ratio of printing paste according to claim 1, characterized in that: A plurality of second ink storage grooves are arranged on the upper surface of the metal screen scraper surface.

9. The metal screen for improving the aspect ratio of printing paste according to claim 8, characterized in that: The structure of the second ink storage tank is set to a shape that is a combination of one or more of a circle, a rectangle, a diamond, a trapezoid, a triangle, and a polygon.

10. The metal screen for improving the aspect ratio of printing paste according to claim 1, characterized in that: The width W3 of the printing holes opened on the printing surface is in the range of 1-40 μm.

11. A metal screen for improving the aspect ratio of printing paste according to claim 4 or 5, characterized in that: The included angle α between the center line of the boss and the center line of the printing hole provided on the printing surface is in the range of 5-90°.

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