Composite fine screen

Abstract

The utility model relates to printing screen technology field especially relates to a kind of composite fine screen, including the fixed connection of graphic layer and screen gauze layer, the graphic layer is provided with several first grid holes consisting of first grid line, and there is no connecting structure in first grid hole;The screen gauze layer includes the warp and weft of staggered arrangement, and the weft in screen gauze layer is perpendicular to the length direction of above-mentioned first grid hole, and screen gauze layer is provided with corresponding no warp area with first grid hole.The utility model is compounded screen gauze on electroforming graphic layer or ink storage layer, and then effectively restricts the opening of grid line on graphic layer, ensures that opening maintains inherent shape in printing process, avoids that silver paste grid line is locally or overall thick, while significantly improves the overall strength of screen, prolongs screen service life.

Description

Technical Field

[0001] This utility model relates to the field of printing screen technology, and in particular to a composite fine grid screen. Background Technology

[0002] In the production process of solar cells, the fine grid plate is the core component for silver paste printing. Its structural design directly affects the printing quality of the silver paste grid lines, the cell conversion efficiency, and the production cost.

[0003] Currently, commonly used fine grid screens are mainly divided into two categories: one is the woven mesh fine grid screen, which uses a mesh composite PI film structure. The PI film forms the fine grid openings, and the mesh plays the role of supporting the screen and providing structural strength. However, due to the presence of yarns and knots, as well as the soft and thin characteristics of the PI film, the silver paste will be blocked by the yarns during the falling process, resulting in low efficiency of the printed silver paste grid lines and high silver paste consumption per unit.

[0004] Another type is the electroformed, fully-opening fine grid screen, where there are no connecting structures within the openings to obstruct the silver paste flow. The rigid, electroformed metal openings effectively constrain the shape of the falling silver paste, resulting in high printing efficiency and low silver paste consumption. However, the lack of any connecting structures within the openings of this type of screen leads to lower opening strength. During printing, the openings are prone to deformation, causing the printed silver paste grid lines to thicken locally or even entirely, resulting in unstable printing performance. Furthermore, the lack of constraint from the slender openings leads to insufficient overall grid strength and a shorter screen lifespan. Therefore, we propose a composite fine grid screen to address these issues. Utility Model Content

[0005] This invention addresses the shortcomings of existing electroformed full-opening fine grid stencils, which lack any connecting structures within the opening, resulting in low opening strength and easy deformation of the opening during printing. It provides a composite fine grid stencil.

[0006] This utility model is achieved through the following technical solution:

[0007] A composite fine grid plate includes a pattern layer and a mesh layer fixedly connected. The pattern layer is provided with a plurality of first grid holes composed of first grid lines, and there are no connecting structures inside the first grid holes.

[0008] The mesh layer includes interlaced warp and weft threads, and the weft threads in the mesh layer are perpendicular to the length direction of the first grid hole. The mesh layer also has warp-free areas corresponding to the first grid hole. By eliminating the yarn obstruction as much as possible through the warp-free areas, the printing smoothness is ensured, efficiency is improved, and unit consumption is reduced.

[0009] In a preferred embodiment of this utility model, a film layer is provided on the mesh layer, and the film layer is provided with through holes corresponding to the first grid holes one by one. The width of the through holes is not less than the width of the first grid holes, and the length of the through holes is not less than the length of the first grid holes. The film layer assists in accurate printing, protects the mesh layer, and maintains the stability of the screen printing structure.

[0010] In a preferred embodiment of this utility model, an ink storage layer is provided between the pattern layer and the mesh layer. The ink storage layer is provided with a plurality of second grid holes composed of second grid lines. The second grid holes correspond one-to-one with the first grid holes and are connected. The width of the second grid hole is greater than the width of the first grid hole, and the length of the second grid hole is not less than the length of the first grid hole. There is no connecting structure inside the second grid hole.

[0011] In a preferred embodiment of this utility model, the first grid hole corresponds one-to-one with the entire fine grid electrode on the solar cell.

[0012] In a preferred embodiment of this utility model, the mesh layer is a woven mesh or an electroformed mesh.

[0013] In a preferred embodiment of this utility model, the woven mesh is stainless steel mesh or tungsten wire mesh.

[0014] In a preferred embodiment of this utility model, the mesh layer is fixed between two adjacent upper and lower layers by adhesive bonding, thereby improving the bonding strength between the mesh layer and the two adjacent upper and lower layers.

[0015] In a preferred embodiment of this utility model, the width of the first gate hole is less than 20 μm, and the thickness of the pattern layer is less than 20 μm.

[0016] In a preferred embodiment of this utility model, both the pattern layer and the ink storage layer are electroformed, and the materials of the pattern layer and the ink storage layer are nickel or nickel alloy.

[0017] In a preferred embodiment of this utility model, the material of the film layer is a PI film.

[0018] The beneficial effects of this utility model are:

[0019] 1. This utility model effectively constrains the opening of the grid lines on the graphic layer or ink storage layer by laminating mesh on the electroformed graphic layer, ensuring that the opening maintains its inherent shape during the printing process, avoiding local or overall thickening of the silver paste grid lines, and significantly improving the overall strength of the screen and extending the service life of the screen.

[0020] 2. In this invention, the thickness of the pattern layer and the ink storage layer can be freely adjusted due to the electroforming process. This results in the yarn of the mesh being suspended above the pattern layer or the ink storage layer, creating a pattern layer or ink storage layer of adjustable thickness between the mesh and the silicon wafer. Compared to traditional woven mesh, the problem of silver paste being blocked by the weft yarn of the mesh is greatly alleviated. At the same time, the additional ink storage layer can store silver paste, further reducing the impact of the weft yarn on the silver paste falling. Combined with the open design of the electroformed pattern layer without connecting structure, printing efficiency is greatly improved and silver paste consumption is reduced.

[0021] In summary, this utility model integrates the structural strength advantages of woven mesh fine grid screen and the high efficiency and low consumption advantages of electroformed fully open fine grid screen, achieving a synergistic effect of stable printing performance, high efficiency, and low unit consumption. Attached Figure Description

[0022] Figure 1 This is an exploded view of a composite fine grid plate according to the first embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the graphic layer in a composite fine grid plate according to the present invention;

[0024] Figure 3 This is a schematic diagram of the mesh layer in a composite fine grid screen according to the present invention;

[0025] Figure 4 This is a schematic diagram of the film layer in a composite fine grid plate according to the present invention;

[0026] Figure 5 This is a partial cross-sectional view of a composite fine grid plate according to the first embodiment of the present invention;

[0027] Figure 6 This is an exploded view of a composite fine grid plate according to the second embodiment of the present invention;

[0028] Figure 7 This is a schematic diagram of the ink storage layer in the second embodiment of the present invention;

[0029] Figure 8 This is a partial cross-sectional view of a composite fine grid plate according to the second embodiment of this utility model.

[0030] In the diagram: 1. Pattern layer; 11. First grid hole; 2. Mesh layer; 21. Warpless area; 3. Ink storage layer; 31. Second grid hole; 4. Film layer; 41. Through-hole. Detailed Implementation

[0031] The preferred embodiments of this utility model will now be described in detail with reference to the accompanying drawings, so that the advantages and features of this utility model can be more easily understood by those skilled in the art, thereby providing a clearer and more definite definition of the scope of protection of this utility model. The directional terms mentioned in this utility model, such as "up," "down," "front," "back," "left," "right," "top," and "bottom," are only for reference to the accompanying drawings. Therefore, the directional terms used are for the purpose of explaining and understanding this utility model, and not for limiting this utility model.

[0032] Example 1:

[0033] like Figure 1-5 The composite fine grid plate shown includes a pattern layer 1 and a mesh layer 2 bonded together with adhesive. The thickness of the pattern layer 1 is less than 20 μm. The pattern layer 1 is provided with a plurality of first grid holes 11 composed of first grid lines. There is no connecting structure inside the first grid hole 11. The width of the first grid hole 11 is less than 20 μm, and the first grid hole 11 corresponds one-to-one with the entire fine grid electrode on the solar cell.

[0034] The mesh layer 2 is a woven mesh or an electroformed mesh. The woven mesh is made of stainless steel mesh or tungsten wire mesh. The mesh layer 2 includes interlaced warp and weft threads, and the weft threads in the mesh layer 2 are perpendicular to the length direction of the first grid hole 11. The mesh layer 2 is provided with a warp-free area 21 corresponding to the first grid hole 11. The warp-free area 21 is used to eliminate yarn obstruction as much as possible, ensuring smooth printing, improving efficiency and reducing unit consumption.

[0035] Secondly, a film layer 4 is provided on the mesh layer 2. The material of the film layer 4 is PI film, and the film layer 4 is provided with through holes 41 that correspond one-to-one with the first grid holes 11. The width of the through holes 41 is not less than the width of the first grid holes 11, and the length of the through holes 41 is not less than the length of the first grid holes 11. The film layer 4 assists in accurate printing, protects the mesh layer 2, and maintains the stability of the screen structure.

[0036] Example 2:

[0037] Reference Figure 2-4 The difference between this embodiment and 6-8, and between this embodiment and 1, is that an ink storage layer 3 is provided between the pattern layer 1 and the mesh layer 2. The ink storage layer 3 is provided with a plurality of second grid holes 31 composed of second grid lines. The second grid holes 31 correspond one-to-one with the first grid holes 11 and are connected. The width of the second grid holes 31 is greater than the width of the first grid holes 11, and the length of the second grid holes 31 is not less than the length of the first grid holes 11. There are no connecting structures inside the second grid holes 31.

[0038] Among them, the mesh layer 2 is fixed between the two adjacent layers by adhesive, which improves the bonding strength between the mesh layer 2 and the two adjacent layers. The adhesive can firmly bond to the graphic layer 1 or the ink storage layer 3, constrain the opening of the grid lines of the graphic layer 1, and ensure that the opening of the screen can maintain its inherent shape during the printing process, so that the ink will not become thicker in some areas or even the whole. In addition, the composite mesh can also significantly improve the overall strength of the screen.

[0039] Furthermore, both the pattern layer 1 and the ink storage layer 3 are electroformed, and the materials of the pattern layer 1 and the ink storage layer 3 are nickel or nickel alloy.

[0040] In this application, by composite mesh layer 2 on the electroformed graphic layer 1 or ink storage layer 3, the overall strength of the fine grid screen is improved, thus solving the problem that the openings in the current electroformed fine grid screen are prone to deformation.

[0041] Meanwhile, since the electroforming process can freely adjust the thickness of the pattern layer 1 and the ink storage layer 3, when the yarn in the mesh layer 2 is suspended on the pattern layer 1, it is separated from the silicon wafer by an adjustable thickness of the pattern layer 1. Therefore, compared with the traditional woven mesh, the low efficiency and high unit consumption of silver paste caused by the weft of the mesh can be greatly alleviated.

[0042] In addition, the extra ink storage layer 3 can store the silver paste, which can further reduce the impact of the mesh weft on the silver paste falling.

[0043] In this application, the electroformed pattern layer 1 not only has the advantage of controllable thickness, but also the electroformed metal opening can effectively constrain the molding shape of the silver paste, enabling the printing of fine grid electrodes with higher aspect ratios.

[0044] This invention combines the advantages of woven mesh fine grid stencils and fully open fine grid stencils, thus possessing the advantages of stable printing performance, high efficiency, and low unit consumption.

[0045] It should be noted that the parts not covered in this utility model are the same as or can be implemented using existing technology; the various drives in this utility model can be implemented by corresponding power structures such as cylinders, oil cylinders, electric cylinders, and motors in conjunction with connecting rods, guide rods, etc., and are not limited to the structures described in the specification and the drawings.

[0046] In the description of the embodiments of this utility model, unless otherwise expressly specified and limited, the terms "installed," "connected," "linked," "set up," "equipped with," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0047] The embodiments described above are merely examples of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A composite fine mesh screen, comprising a pattern layer (1) and a mesh layer (2) fixedly connected, characterized in that: The graphic layer (1) is provided with a plurality of first grid holes (11) composed of first grid lines, and there is no connecting structure inside the first grid holes (11); The mesh layer (2) includes warp and weft threads arranged in an alternating manner, and the weft threads in the mesh layer (2) are perpendicular to the length direction of the first grid hole (11) and the mesh layer (2) is provided with a warp-free area (21) corresponding to the first grid hole (11).

2. The composite fine grid plate according to claim 1, characterized in that: A membrane layer (4) is provided on the mesh layer (2), and a through-hole (41) corresponding to the first grid hole (11) is provided on the membrane layer (4). The width of the through-hole (41) is not less than the width of the first grid hole (11), and the length of the through-hole (41) is not less than the length of the first grid hole (11).

3. The composite fine grid plate according to claim 2, characterized in that: An ink storage layer (3) is provided between the graphic layer (1) and the mesh layer (2). The ink storage layer (3) is provided with a plurality of second grid holes (31) composed of second grid lines. The second grid holes (31) correspond one-to-one with the first grid holes (11) and are connected. The width of the second grid hole (31) is greater than the width of the first grid hole (11), and the length of the second grid hole (31) is not less than the length of the first grid hole (11). There is no connecting structure inside the second grid hole (31).

4. The composite fine grid plate according to claim 3, characterized in that: The first grid hole (11) corresponds one-to-one with the entire fine grid electrode on the solar cell.

5. A composite fine grid plate according to claim 3, characterized in that: The mesh layer (2) is a woven mesh or an electroformed mesh.

6. A composite fine grid plate according to claim 5, characterized in that: The woven mesh is made of stainless steel or tungsten wire.

7. A composite fine grid plate according to claim 5, characterized in that: The mesh layer (2) is fixed between two adjacent layers by adhesive.

8. A composite fine grid plate according to claim 3, characterized in that: The width of the first gate hole (11) is less than 20 μm, and the thickness of the pattern layer (1) is less than 20 μm.

9. A composite fine grid plate according to claim 8, characterized in that: The pattern layer (1) and the ink storage layer (3) are both formed by electroforming, and the materials of the pattern layer (1) and the ink storage layer (3) are nickel or nickel alloy.

10. A composite fine grid plate according to claim 2, characterized in that: The material of the film layer (4) is a PI film.

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