High-low point coating plate roller and diaphragm

Abstract

The utility model relates to the technical field of diaphragm processing, and provides a high-low point coating plate roller, which is used for coating slurry on a diaphragm in a point coating manner, and comprises a roller body and a plate roller layer, the plate roller layer is arranged on the roller body, a plurality of point coating parts are arranged on the plate roller layer, and at least two of the point coating parts are different in height and used for carrying different amounts of coating slurry. The roller body is used for driving the plate roller layer to rotate and enabling the dispensing part to approach the diaphragm. According to the technical scheme, the problem that the bonding effect between the diaphragm and the pole piece is poor due to the fact that the pole piece is uneven in the hot pressing process of the diaphragm and the pole piece in the prior art is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of diaphragm processing, and in particular to a high and low dot coating roller and a diaphragm. Background Art

[0002] As one of the key internal components of lithium batteries, the performance of battery separators plays a decisive role in the battery's interface structure and internal resistance, directly affecting the battery's capacity, cycle and safety performance. It is crucial to improving the battery's overall performance and determines key characteristics such as battery capacity, cycle performance, and charging current density.

[0003] Currently, roller coating and spray coating are the most mature processes for producing separators. Roller coating produces uniform and controllable separator thickness, but it also suffers from high air permeability, which increases the battery's internal resistance and, in turn, affects battery cycle performance. Spray coating offers advantages over roller coating, such as low air permeability, material savings, and cost reduction. However, it also suffers from the drawbacks of random spraying points and uncontrollable size and shape.

[0004] As a new coating process, spot coating has many advantages. During coating, the slurry is transferred to the plate roller through the anilox roller, so that the convex points on the surface of the plate roller are filled with material. The slurry on the convex points is then transferred to the diaphragm through the rotation of the plate roller, forming a uniform and dense dot glue layer on the diaphragm, which is then bonded to the electrode through hot pressing. Spot coating can control the morphology of each convex point and accurately control the coverage of the diaphragm. The thickness of the diaphragm can also be adjusted by parameters such as the plate roller, anilox roller, and vehicle speed, which can better meet the battery's requirements for the diaphragm. The height of the convex points on the traditional plate roller is consistent, so that the diaphragm has the same dot glue layer thickness after coating. However, in the later hot pressing process, due to the unevenness of the electrode electrode, the bonding effect between the diaphragm and the electrode will be poor, thus affecting the performance of the battery.

[0005] The existing technology has not solved the above problems well, which has brought troubles to the normal work in this field. Therefore, there is an urgent need for a high and low dot coating roller and a diaphragm to solve the above problems. Utility Model Content

[0006] The utility model provides a high and low dot coating roller and a diaphragm, which solves the problem in the related art that during the hot pressing process of the diaphragm and the electrode piece, the bonding effect between the diaphragm and the electrode piece is poor due to the unevenness of the electrode piece.

[0007] The technical solution of the utility model is as follows: a high and low dot coating roller, used for dot coating slurry on the diaphragm, comprising a roller body and a plate roller layer, the plate roller layer being arranged on the roller body, the plate roller layer having a plurality of dot coating parts, at least two of the plurality of dot coating parts having different heights, for carrying different amounts of coating slurry, the roller body being used to drive the plate roller layer to rotate and bring the dot coating parts close to the diaphragm.

[0008] Optionally, the inner wall of the plate roller layer has anti-slip grooves, and an angle is formed between the anti-slip grooves and the horizontal plane.

[0009] Optionally, the inner wall of the plate roller layer has bosses, and the roller body has grooves. The bosses and grooves are the same in number and are evenly distributed along the circumference of the roller body. The bosses are used to engage with the grooves.

[0010] Optionally, the inner wall of the plate roller layer is a smooth surface, the interior of the roller body has a cavity, the surface of the roller body is evenly distributed with negative pressure holes, and also includes a negative pressure air pipe, one end of the negative pressure air pipe is connected to the cavity of the roller body, and the other end is used to connect to the negative pressure generating unit.

[0011] Optionally, the roller body is covered with a plurality of the plate roller layers, and the adjacent plate roller layers are spliced together by means of a clamping structure, and the clamping structure includes a clamping portion and a clamping groove, and the clamping portion and the clamping groove are respectively arranged on two adjacent plate roller layers, and the clamping portion and the clamping groove are both trapezoidal.

[0012] Optionally, the cross-sectional shape of the dot coating portion is at least one of a circle, a square, a regular hexagon and a triangle.

[0013] Optionally, the dot coating parts form a group of three, and the heights of the three dot coating parts in a group gradually increase or decrease, and there are multiple groups of the dot coating parts arranged along the axial direction of the plate roller layer.

[0014] Optionally, the dot coating parts are arranged in groups of six, and the six dot coating parts in a group are arranged in pairs of two. The two pairs on both sides of the three pairs of dot coating parts have the same height, and the height of the middle pair is lower than the height of the two pairs on both sides. There are multiple groups of dot coating parts arranged along the axial direction of the plate roller layer.

[0015] Optionally, the dot coating parts are arranged in a group of four, and among the four dot coating parts in a group, the first and the third have the same height, the third and the fourth have the same height, and the first and the third have lower heights than the third and the fourth, and there are multiple groups of the dot coating parts arranged along the axial direction of the plate roller layer.

[0016] A diaphragm is formed by dot coating using a high-low dot coating roller, comprising a base film and a dot coating layer. The dot coating layer has different heights at different locations, and the dot coating layer is formed when the dot coating portion carries a coating slurry and contacts the base film.

[0017] The working principle and beneficial effects of the utility model are as follows:

[0018] The high-low dot coating roller consists of a roller body and a roller layer. The roller layer is tightly wrapped around the roller body and is distributed with multiple dot coating sections of varying heights. In actual operation, the slurry is first transferred to the roller layer via an anilox roller. Due to the different heights of the dot coating sections, the dot coating sections at different heights carry different amounts of coating slurry. The roller body then drives the roller layer to rotate, bringing the dot coating section close to the diaphragm. When the dot coating section contacts the diaphragm, the carried slurry is transferred to the diaphragm, forming a dot coating layer of varying heights on the diaphragm. The diaphragm with the dot coating layer then comes into contact with the uneven surface of the electrode during the hot pressing process. The dot coating layers of varying heights can better adapt to the uneven surface of the electrode, generating adhesion, effectively increasing the effective contact area between the diaphragm and the electrode, and strengthening the adhesion between the two.

[0019] When designing the height of the spot coating part, it is necessary to consider the height of the spot coating layer formed on the diaphragm, which should correspond to the unevenness of various parts on the electrode. In other words, the high and low points of the spot coating layer should correspond to the low and high points of the electrode surface respectively.

[0020] By providing dispensing sections of varying heights, a dispensing layer of varying heights is formed on the diaphragm. During hot pressing with the electrode, this varying coating better conforms to the uneven surface of the electrode, significantly increasing the effective contact area between the diaphragm and the electrode, and improving adhesion. This effectively prevents separation of the electrode and diaphragm due to the diaphragm falling off, thereby improving battery life and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The preferred embodiments will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present invention.

[0022] Figure 1 It is a structural diagram of the plate roller layer;

[0023] Figure 2 Schematic diagram of the structure of the roller body;

[0024] Figure 3 It is a schematic diagram of the structure when the dot coating part adopts a sequential arrangement;

[0025] Figure 4 This is a schematic diagram of the structure when the dot coating part is arranged in another order;

[0026] Figure 5 It is a structural diagram of the coating part when another sequential arrangement is adopted;

[0027] Figure 6 Schematic diagram of the structure of the inner wall of the plate roller layer;

[0028] Figure 7 Schematic diagram of the structure of the negative pressure hole;

[0029] Figure 8 It is a structural diagram of the splicing of the plate roller layers;

[0030] Figure 9 Schematic diagram of the structure when the diaphragm and the electrode are bonded.

[0031] In the figure: 1. Roller body, 2. Plate roller layer, 3. Dot coating part, 4. Anti-slip groove, 5. Boss, 6. Groove, 7. Negative pressure hole, 8. Negative pressure air pipe, 9. Clamping structure, 10. Clamping part, 11. Clamping slot, 12. Base film, 13. Dot coating layer, 14. Pole piece. DETAILED DESCRIPTION

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without inventive work.

[0033] To simplify the drawings, only the parts relevant to the utility model are schematically shown in each figure; they do not represent the actual structure of the product. Furthermore, to simplify the drawings and facilitate understanding, in some figures, only one of the components with the same structure or function is schematically shown or labeled. In this document, "one" not only means "only one" but also "more than one," and "several" includes "two" and "more than two."

[0034] It should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances.

[0035] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0036] Reference Figures 1 to 9, which is the first embodiment of the utility model, proposes a high and low dot coating roller for dot coating slurry on the diaphragm, including a roller body 1 and a plate roller layer 2, the plate roller layer 2 is arranged on the roller body 1, and the plate roller layer 2 has a plurality of dot coating parts 3, at least two of the plurality of dot coating parts 3 have different heights and are used to carry different amounts of coating slurry, the roller body 1 is used to drive the plate roller layer 2 to rotate and make the dot coating part 3 close to the diaphragm.

[0037] In this embodiment, the high-low dot coating roller includes a roller body 1 and a roller layer 2. The roller layer 2 is tightly wrapped on the roller body 1, and multiple dot coating parts 3 of different heights are distributed on the roller layer 2. In actual operation, the slurry is first transferred to the roller layer 2 through the anilox roller. Since the dot coating parts 3 are of different heights, the dot coating parts 3 of different heights will carry different amounts of coating slurry. Then the roller body 1 drives the roller layer 2 to rotate, so that the dot coating parts 3 are close to the diaphragm. When the dot coating parts 3 come into contact with the diaphragm, the slurry carried is transferred to the diaphragm, thereby forming a dot glue layer 13 of different heights on the diaphragm. Afterwards, the diaphragm with the dot glue layer 13 comes into contact with the uneven surface of the electrode 14 during the hot pressing process. The dot glue layers 13 of different heights can better adapt to the uneven surface of the electrode 14, generate bonding force, effectively increase the effective contact area between the diaphragm and the electrode 14, and enhance the bonding force between the two.

[0038] When designing the height of the dot-coated portion 3, the height of the dot-coated glue layer formed on the diaphragm must be taken into consideration, and should correspond to the unevenness of various locations on the electrode 14. In other words, the high points and low points of the dot-coated glue layer should correspond to the low points and high points on the surface of the electrode 14 as much as possible.

[0039] By providing the dot coating portions 3 at varying heights, a dot coating layer 13 of varying heights can be formed on the diaphragm. During hot pressing with the electrode 14, this varying coating can better conform to the uneven surface of the electrode 14, significantly increasing the effective contact area between the diaphragm and the electrode 14 and improving the bonding strength. This effectively prevents the diaphragm from falling off the electrode 14 and causing separation between the electrode 14 and the diaphragm, thereby improving the battery life and safety.

[0040] Furthermore, the inner wall of the plate roller layer 2 has anti-slip grooves 4, and an angle is formed between the anti-slip grooves 4 and the horizontal plane.

[0041] Furthermore, the inner wall of the plate roller layer 2 has bosses 5, and the roller body 1 has grooves 6. The bosses 5 and the grooves 6 are the same in number and are evenly distributed along the circumference of the roller body 1. The bosses 5 are used to engage with the grooves 6.

[0042] In this embodiment, the inner wall of the roller layer 2 of the high-low dot coating roller is provided with anti-slip grooves 4, which are arranged at an angle with the horizontal plane. The inner wall of the roller layer 2 also has bosses 5, and the roller body 1 has corresponding grooves 6. When installing the roller layer 2, the roller layer 2 is placed on the roller body 1 so that the bosses 5 on the inner wall of the roller layer 2 engage with the grooves 6 on the roller body 1. During operation, the roller body 1 drives the roller layer 2 to rotate. When the dot coating portion 3 on the roller layer 2 contacts the diaphragm for dot coating, friction is generated between the anti-slip grooves 4 and the diaphragm. Because the anti-slip grooves 4 have a specific angle, they effectively prevent the roller layer 2 from slipping during rotation. The clamping structure 9 of the boss 5 and the groove 6 ensures that the plate roller layer 2 always maintains a stable connection with the roller body 1 during high-speed rotation, and no relative sliding occurs, thereby enhancing the connection stability between the plate roller layer 2 and the roller body 1, ensuring the overall stability of the plate roller during high-speed rotation and dot coating, and improving the dot coating quality and production efficiency.

[0043] Furthermore, the inner wall of the plate roller layer 2 is a smooth surface, the roller body 1 has a cavity inside, the surface of the roller body 1 is evenly distributed with negative pressure holes 7, and also includes a negative pressure air pipe 8, one end of the negative pressure air pipe 8 is connected to the cavity of the roller body 1, and the other end is used to connect to the negative pressure generating unit.

[0044] In this embodiment, the inner wall of the roller layer 2 of the high-low dot coating roller is smooth, and the interior of the roller body 1 is hollow. Negative pressure holes 7 are evenly distributed on the surface of the roller body 1. A negative pressure air pipe 8 is also provided. One end of the negative pressure air pipe 8 is connected to the roller body 1 via a rotary joint to ensure that it does not affect the rotation of the roller body 1. The other end is used to connect to a negative pressure generating unit. During operation, the negative pressure generating unit is activated, and negative pressure is generated inside the roller body 1 through the negative pressure air pipe 8. Because the negative pressure holes 7 are connected to the interior of the roller body 1, the negative pressure causes the roller layer 2 to be tightly attached to the roller body 1. Since the inner wall of the roller layer 2 is smooth, it can ensure sufficient contact with the roller body 1. During the rotation of the roller body 1, the roller layer 2 can rotate stably with the roller body 1 without relative sliding or falling off.

[0045] By providing a negative pressure air pipe 8 connected to the negative pressure generating unit, the negative pressure hole 7 is used to adsorb the roller layer 2 onto the roller body 1, ensuring the stability of the roller layer 2 during operation. The smooth surface of the inner wall of the roller layer 2 ensures sufficient contact with the roller body 1, further enhancing the adsorption effect. This structural design ensures that the roller layer 2 can always be firmly fixed to the roller body 1 during high-speed rotation and the spot coating process, improving the accuracy and quality of the spot coating.

[0046] Furthermore, the roller body 1 is covered with a plurality of the plate roller layers 2, and the adjacent plate roller layers 2 are spliced with the help of a clamping structure 9, and the clamping structure 9 includes a clamping portion 10 and a clamping groove 11, and the clamping portion 10 and the clamping groove 11 are respectively arranged on two adjacent plate roller layers 2, and the clamping portion 10 and the clamping groove 11 are both trapezoidal.

[0047] In this embodiment, the roller body 1 of the high and low dot coating roller is coated with multiple roller layers 2, and adjacent roller layers 2 are spliced together with the help of a clamping structure 9. The clamping structure 9 includes a clamping portion 10 and a clamping groove 11. The clamping portion 10 is arranged on one of the roller layers 2, and the clamping groove 11 is arranged on another adjacent roller layer 2. When the roller needs to be assembled, the clamping portion 10 of one roller layer 2 is aligned with the clamping groove 11 of another roller layer 2, and then the splicing and installation are carried out. Since the clamping portion 10 and the clamping groove 11 are both trapezoidal, a tight fit can be achieved during the splicing process. During operation, the roller body 1 rotates, driving the multiple roller layers 2 to rotate synchronously. When the dot coating operation is performed, the dot coating portion 3 on each roller layer 2 carries the slurry to contact the diaphragm and transfers the slurry to the diaphragm. If diaphragms of different widths need to be coated, an appropriate number of roller layers 2 can be selected for splicing according to actual needs to meet different production requirements.

[0048] Multiple separate stencil roller layers 2 are arranged on the roller body 1, allowing the roller to adapt to the coating requirements of membranes of varying widths, improving the versatility and flexibility of the equipment. Adjacent stencil roller layers 2 are connected by a snap-fit structure 9, ensuring synchronous rotation of the multiple layers and improving the stability and consistency of the dot coating. The snap-fit structure 9 utilizes a trapezoidal clamping portion 10 and a slot 11, ensuring a tight connection between adjacent stencil roller layers 2, reducing the possibility of loosening or misalignment during rotation and improving the reliability and service life of the equipment.

[0049] Furthermore, the cross-sectional shape of the dot-coating portion 3 is at least one of a circle, a square, a regular hexagon and a triangle.

[0050] In this embodiment, the high-low dot coating roller has multiple dot coating sections 3 on its roller layer 2. The cross-sectional shape of these dot coating sections 3 can be one or a combination of circular, square, regular hexagonal, and triangular. For example, to meet specific coating requirements, some dot coating sections 3 can be designed as circular to achieve a more uniform coating effect; in other cases, some dot coating sections 3 can be designed as square or regular hexagonal to meet different requirements for the dispensing layer 13. In actual production, the cross-sectional shape of the dot coating sections 3 can be flexibly selected and adjusted according to the specific requirements of the battery separator and the characteristics of the production process to achieve the optimal coating effect.

[0051] Furthermore, the dot coating parts 3 form a group of three, and the heights of the three dot coating parts 3 in a group gradually increase or decrease. There are multiple groups of the dot coating parts 3 arranged along the axial direction of the plate roller layer 2.

[0052] Furthermore, the dot coating parts 3 are arranged in groups of six, and the six dot coating parts 3 in a group are arranged in pairs of two. The two pairs on both sides of the three pairs of dot coating parts 3 have the same height, and the height of the middle pair is lower than the height of the two pairs on both sides. There are multiple groups of dot coating parts 3 arranged along the axial direction of the plate roller layer 2.

[0053] Furthermore, the dot coating parts 3 are grouped into four, and among the four dot coating parts 3 in a group, the first and the third have the same height, the third and the fourth have the same height, and the first and the third have lower heights than the third and the fourth. There are multiple groups of the dot coating parts 3 arranged along the axial direction of the plate roller layer 2.

[0054] In this embodiment, a plurality of dot coating portions 3 are distributed on the plate roller layer 2 of the high and low dot coating roller. These dot coating portions 3 are arranged in groups in a sequence of various height changes, and multiple groups are provided, for example:

[0055] The dot coating portions 3 are arranged in groups of three, and in the same group, the heights of the three dot coating portions 3 are gradually increased or decreased. In addition, there are multiple groups of such dot coating portions 3 arranged along the axial direction of the plate roller layer 2.

[0056] Alternatively, they are arranged in groups of six, with two pairs forming a pair within the same group. The two pairs on either side of the three pairs of dot coating portions 3 are designed to be the same height, while the pair in the middle is designed to be lower than the height of the two pairs. Furthermore, multiple groups of such dot coating portions 3 are arranged along the axial direction of the plate roller layer 2.

[0057] Alternatively, the dot coating portions 3 may be arranged in groups of four, wherein the first and third dot coating portions 3 in a group have the same height, the second and fourth dot coating portions 3 have the same height, and the first and third dot coating portions 3 have lower heights than the second and fourth dot coating portions 3. There may be multiple groups of such dot coating portions 3 arranged along the axial direction of the plate roller layer 2.

[0058] During operation, as the plate roller layer 2 rotates with the roller body 1 and the dot coating portion 3 approaches and contacts the diaphragm, the varying heights of the dot coating portions 3 within a group form a dotted adhesive layer 13 of varying heights on the diaphragm. When the diaphragm with this dotted adhesive layer 13 is hot-pressed against the uneven surface of the electrode 14, the dotted adhesive at varying heights better adapts to the uneven surface of the electrode 14, ensuring a larger contact area. This varying height design ensures a tighter fit between the dotted adhesive layer 13 and the electrode 14, significantly improving the bond strength.

[0059] By designing the dot coating parts 3 as a group with varying heights, the dot coating layer 13 formed on the diaphragm has a characteristic of varying height. This feature can significantly increase the contact area during hot pressing with the uneven electrode 14, thereby effectively improving the bonding strength. This design improves the connection stability between the battery diaphragm and the electrode 14, reduces battery performance issues caused by poor bonding, and helps to improve the battery life and safety. At the same time, the arrangement of multiple groups of such dot coating parts 3 ensures the uniformity and consistency of the dot coating, providing a reliable guarantee for the high-quality production of batteries.

[0060] A diaphragm is formed by dot coating using a high-low dot coating roller, comprising a base film 12 and a dot coating layer 13. The dot coating layer 13 has different heights at different locations. The dot coating layer 13 is formed when the dot coating part 3 carries the coating slurry and contacts the base film 12.

[0061] In this embodiment, the high and low dot coating roller includes a roller body 1 and a roller layer 2, and the roller layer 2 is provided with a plurality of dot coating parts 3 of different heights. During the dot coating process, the slurry is transferred to the roller layer 2 through the anilox roller, and the dot coating parts 3 of different heights carry different amounts of coating slurry. The roller body 1 drives the roller layer 2 to rotate so that the dot coating part 3 is close to the base film 12. When the dot coating part 3 contacts the base film 12, the carried slurry is transferred to the base film 12 to form a dot coating layer 13. Since the dot coating parts 3 have different heights, the heights of the dot coating layer 13 are also different at different places. In the subsequent hot pressing process, the diaphragm with the dot coating layer 13 of different heights contacts the electrode 14 with an uneven surface. The dot coating layer 13 can better adapt to the uneven surface of the electrode 14, thereby obtaining a larger contact area and ensuring good bonding strength.

[0062] This type of separator is produced using a high-low dot coating roller, with the dotted adhesive layer 13 having varying heights. During hot pressing with the electrode 14, it can better adapt to the uneven surface of the electrode 14, increasing the contact area and improving the bonding strength. This helps improve the overall performance and stability of the battery and reduces battery failures caused by poor bonding.

[0063] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, and all of these should be included in the scope of the claims of the present invention.

Claims

1. A high and low dot coating roller, characterized in that: The invention relates to a device for spot-coating a coating slurry onto a diaphragm, comprising a roller body (1) and a plate roller layer (2), wherein the plate roller layer (2) is arranged on the roller body (1), and the plate roller layer (2) has a plurality of spot coating portions (3), at least two of the plurality of spot coating portions (3) having different heights and being used to carry different amounts of coating slurry, and the roller body (1) is used to drive the plate roller layer (2) to rotate and to bring the spot coating portions (3) close to the diaphragm.

2. A high and low dot coating roller according to claim 1, characterized in that: The inner wall of the plate roller layer (2) has anti-skid patterns (4), and an angle is formed between the anti-skid patterns (4) and the horizontal plane.

3. A high and low dot coating roller according to claim 2, characterized in that: The inner wall of the plate roller layer (2) has a boss (5), and the roller body (1) has a groove (6). The bosses (5) and the grooves (6) are the same in number and are evenly distributed along the circumference of the roller body (1). The bosses (5) are used to engage with the grooves (6).

4. The high-low dot coating roller according to claim 1, characterized in that: The inner wall of the plate roller layer (2) is a smooth surface, the roller body (1) has a cavity inside, the surface of the roller body (1) is uniformly distributed with negative pressure holes (7), and also includes a negative pressure air pipe (8), one end of the negative pressure air pipe (8) is connected to the cavity of the roller body (1), and the other end is used to connect to a negative pressure generating unit.

5. The high-low dot coating roller according to claim 1, characterized in that: The roller body (1) is covered with a plurality of plate roller layers (2), and adjacent plate roller layers (2) are spliced together by means of a clamping structure (9). The clamping structure (9) comprises a clamping portion (10) and a clamping groove (11). The clamping portion (10) and the clamping groove (11) are respectively provided on two adjacent plate roller layers (2), and both the clamping portion (10) and the clamping groove (11) are trapezoidal.

6. The high-low dot coating roller according to claim 1, characterized in that: The cross-sectional shape of the dot coating portion (3) is at least one of a circle, a square, a regular hexagon and a triangle.

7. The high-low dot coating roller according to claim 1, characterized in that: The dot coating parts (3) form a group of three, and the heights of the three dot coating parts (3) in a group gradually increase or decrease. The dot coating parts (3) are arranged in multiple groups along the axial direction of the plate roller layer (2).

8. The high-low dot coating roller according to claim 1, characterized in that: The dot coating parts (3) are arranged in groups of six, and the six dot coating parts (3) in a group are arranged in pairs of two. The two pairs on both sides of the three pairs of dot coating parts (3) have the same height, and the height of the middle pair is lower than the height of the two pairs on both sides. The dot coating parts (3) are arranged in multiple groups along the axial direction of the plate roller layer (2).

9. The high-low dot coating roller according to claim 1, characterized in that: The dot coating parts (3) are arranged in groups of four. Among the four dot coating parts (3) in a group, the first and third ones have the same height, the third and fourth ones have the same height, and the first and third ones have lower heights than the third and fourth ones. The dot coating parts (3) are arranged in multiple groups along the axial direction of the plate roller layer (2).

10. A diaphragm, produced by dot coating using a high-low dot coating roller according to any one of claims 1 to 9, characterized in that: The invention comprises a base film (12) and a glue dot layer (13), wherein the height of each part of the glue dot layer (13) is different, and the glue dot layer (13) is formed after the coating slurry is brought into contact with the base film (12) by the coating portion (3).

Images