Heating film, preparation method of heating film and heating glass

Abstract

The invention discloses a heating film, a preparation method of the heating film and heating glass. The heating film comprises a substrate, a metal grid, a first electrode and a second electrode, the substrate comprises a plurality of heating areas arranged along a first direction; the metal grid is located on one side of the substrate, and the metal grid is arranged in the heating area; the first electrode and the second electrode are located on the two opposite sides of the substrate in the second direction respectively, the first electrode and the second electrode are both electrically connected with the metal grid, and the first direction intersects with the second direction; wherein the sheet resistance of the metal grid arranged in the heating area is related to the length of the heating area in the first direction and / or the length of the heating area in the second direction. The heating film provided by the invention is uniform in heating.

Description

Technical Field

[0001] The present invention relates to the technical field of heating films, and in particular to a heating film, a preparation method of the heating film, and a heating glass. Background Art

[0002] With the progress of technology and the improvement of people's living standards, a variety of sensing functional devices are integrated on automobile windows or vehicle lights to monitor the surrounding road conditions, such as radar antennas, sensors, cameras, etc. When there is rain, snow or fog on the window or the light, it will seriously affect the normal operation of the functional devices and endanger driving safety. To avoid the above situation, a heating film is provided on the surface of the automobile window or vehicle light integrated with the functional devices, and then the rain, snow and fog attached to its surface are heated and removed without affecting the visual effect.

[0003] Currently, the material commonly used for the heating film on the window is a metal wire, and a series circuit layout is performed on the metal wire to obtain a heating effect. In order not to affect the visual effect, the distance between the metal wires is relatively large. When heating, the heating is concentrated near the metal wires, resulting in poor heating uniformity. To solve the above problems, it is proposed to use indium tin oxide (ITO) materials, metal nanowires or carbon materials to achieve a transparent and uniform heating effect.

[0004] However, currently, the areas covered by vehicle lights or functional devices are usually irregular shapes, such as ellipses, trapezoids or polygons, etc. The above indium tin oxide (ITO), metal nanowire or carbon material thin films usually can only form a single sheet resistance material (i.e., uniformly conductive on the whole surface) on the substrate surface. When used in irregular areas, the heating uniformity will be very poor due to uneven electric field distribution. Summary of the Invention

[0005] The present invention provides a heating film, a preparation method of the heating film, and a heating glass to solve the problem of poor heating uniformity of the existing heating film.

[0006] In a first aspect, an embodiment of the present invention provides a heating film, including a substrate, a metal grid, a first electrode and a second electrode;

[0007] The substrate includes a plurality of heating regions arranged along a first direction;

[0008] The metal grid is located on one side of the substrate, and the metal grid is disposed in the heating region;

[0009] The first electrode and the second electrode are respectively located on opposite sides of the substrate along a second direction, and both the first electrode and the second electrode are electrically connected to the metal grid, and the first direction intersects with the second direction;

[0010] Among them, the sheet resistance of the metal grid arranged in the heating area is related to the length of the heating area in the first direction and / or the length of the heating area in the second direction.

[0011] Optionally, the sheet resistance of the metal grid arranged in the heating area is positively correlated with the length of the heating area in the first direction.

[0012] Optionally, the sheet resistance of the metal grid arranged in the heating area is negatively correlated with the length of the heating area in the second direction.

[0013] Optionally, the plurality of heating areas include a first heating area and a second heating area, and the metal grid includes a first metal grid arranged in the first heating area and a second metal grid arranged in the second heating area;

[0014] The sheet resistance of the first metal grid is less than that of the second metal grid;

[0015] The grid period of the first metal grid is less than that of the second metal grid, and / or, the resistivity of the first metal grid is less than that of the second metal grid, and / or, the grid line width of the first metal grid is greater than that of the second metal grid, and / or, the thickness of the first metal grid is greater than that of the second metal grid.

[0016] Optionally, the plurality of heating areas include a third heating area and a fourth heating area, and the metal grid includes a third metal grid arranged in the third heating area and a fourth metal grid arranged in the fourth heating area;

[0017] The third metal grid is electrically connected to the fourth metal grid.

[0018] Optionally, the plurality of heating areas include a fifth heating area and a sixth heating area, and the metal grid includes a fifth metal grid arranged in the fifth heating area and a sixth metal grid arranged in the sixth heating area;

[0019] The percentage difference P1 between the resistance of the fifth metal grid and the resistance of the sixth metal grid satisfies 0% ≤ P1 ≤ 10%.

[0020] Optionally, the temperature difference K1 between the heating area with the maximum temperature and the heating area with the minimum temperature satisfies 0°C ≤ K1 ≤ 15°C.

[0021] In a second aspect, an embodiment of the present invention provides a method for preparing a heating film for preparing the heating film as described in the first aspect, and the preparation method includes:

[0022] Prepare a substrate, wherein the substrate includes a plurality of heating regions arranged in a first direction;

[0023] Prepare a metal grid on one side of the substrate, wherein the metal grid is disposed in the heating region, and the sheet resistance of the metal grid is related to the length of the heating region in the first direction and / or the length of the heating region in a second direction, and the first direction intersects with the second direction;

[0024] Prepare a first electrode and a second electrode, wherein the first electrode and the second electrode are respectively located on two opposite sides of the substrate along the second direction, and both the first electrode and the second electrode are electrically connected to the metal grid.

[0025] Optionally, preparing a metal grid on one side of the substrate includes:

[0026] Determine a preset resistance of the heating film according to a preset heating power, a preset heating temperature, a preset driving voltage, and a preset heating uniformity requirement;

[0027] Determine a preset regional resistance of the heating region according to the preset resistance and the preset number of the heating regions;

[0028] Determine theoretical data of the metal grid of each heating region according to the preset regional resistance, the length of the heating region in the first direction, and the length of the heating region in the second direction, where the theoretical data includes at least one of a theoretical grid line width, a theoretical grid period, a theoretical grid thickness, and a theoretical grid resistivity;

[0029] Perform simulation analysis on the heating performance of the heating film according to the theoretical data and a simulation software to obtain a simulation analysis result;

[0030] Adjust the theoretical data according to the simulation analysis result until the simulation analysis result meets the preset requirements, and prepare the metal grid on one side of the substrate according to the adjusted theoretical data.

[0031] In a third aspect, an embodiment of the present invention provides a heating glass, including the heating film as described in the first aspect.

[0032] The technical solution of the embodiment of the present invention is related to the sheet resistance of the metal grid disposed in the heating region being related to the length of the heating region in the first direction and / or the length of the heating region in the second direction, and the sheet resistance of the metal grid of each heating region can be set according to the length of each heating region in the first direction and / or the length of each heating region in the second direction, so that the resistance of the metal grid of each heating region is consistent, which is beneficial to improving the heating uniformity of the heating film.

[0033] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0035] Figure 1 Structural schematic diagram of a substrate provided for an embodiment of the present invention;

[0036] Figure 2 Structural schematic diagram of a heating film provided for an embodiment of the present invention;

[0037] Figure 3 Another structural schematic diagram of a substrate provided for an embodiment of the present invention;

[0038] Figure 4 Another structural schematic diagram of a heating film provided for an embodiment of the present invention;

[0039] Figure 5 Flowchart of a method for preparing a heating film provided for an embodiment of the present invention;

[0040] Figure 6 Flowchart of another method for preparing a heating film provided for an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of the present invention are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices. The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only used to illustrate the relative positional relationship between each component or component part, and does not particularly limit the specific installation orientation of each component or component part.

[0043] Figure 1 It is a schematic structural diagram of a substrate provided by an embodiment of the present invention. Figure 2 It is a schematic structural diagram of a heating film provided by an embodiment of the present invention. Refer to Figure 1 and Figure 2 In the heating film in the embodiment of the present invention, the heating film includes a substrate 10, a metal grid 20, a first electrode 30 and a second electrode 40. The substrate 10 includes a plurality of heating regions 11 arranged along a first direction Y. The metal grid 20 is located on one side of the substrate 10, and the metal grid 20 is disposed in the heating region 11. The first electrode 30 and the second electrode 40 are respectively located on opposite sides of the substrate 10 along a second direction X, and both the first electrode 30 and the second electrode 40 are electrically connected to the metal grid 20, and the first direction Y intersects the second direction X. Wherein, the sheet resistance of the metal grid 20 disposed in the heating region 11 is related to the length of the heating region 11 in the first direction Y and / or the length of the heating region 11 in the second direction X.

[0044] Exemplarily, by setting different voltages applied to the first electrode 30 and the second electrode 40, current can pass through the metal grid 20 disposed in the heating region 11 and electrically connected to the first electrode 30 and the second electrode 40. When current passes through the metal grid 20, heat will be generated, thereby realizing the electrothermal function of the heating film.

[0045] Exemplarily, the first direction Y and the second direction X in the embodiment of the present invention may be perpendicular to each other. It can be understood that the resistance of the metal grid 20 disposed in the heating region 11, the sheet resistance of the metal grid 20 disposed in the heating region 11, the length of the heating region 11 in the first direction Y, and the length of the heating region 11 in the second direction X satisfy the following corresponding relationship:

[0046]

[0047] Among them, R represents the resistance of the metal grid 20 provided in the heating area 11, and R s represents the sheet resistance of the metal grid 20 provided in the heating area 11, W represents the length of the heating area 11 in the first direction Y, and L represents the length of the heating area 11 in the second direction X.

[0048] From the above corresponding relationship, it can be seen that in the case of different heating areas 11, that is, when the length of the heating area 11 in the first direction Y is different and / or the length of the heating area 11 in the second direction X is different, the sheet resistance of the metal grid 20 provided in the heating area 11 can be set according to the specific correlation between the sheet resistance of the metal grid 20 provided in the heating area 11 and the length of the heating area 11 in the first direction Y and / or the length of the heating area 11 in the second direction X, so as to make the resistances of the metal grids 20 provided in each heating area 11 consistent. It should be noted that the fact that the resistances of the metal grids 20 provided in each heating area 11 are consistent means that the resistances of the metal grids 20 provided in each heating area 11 are equal or substantially equal.

[0049] In the embodiment of the present invention, by setting the sheet resistance of the metal grid 20 located in the heating area 11 to be related to the length of the heating area 11 in the first direction Y and / or the length of the heating area 11 in the second direction X, the sheet resistance of the metal grid 20 in each heating area 11 can be set according to the length of each heating area 11 in the first direction Y and / or the length of each heating area 11 in the second direction X, so as to make the resistances of the metal grids 20 in each heating area 11 consistent, which is beneficial to improving the heating uniformity of the heating film.

[0050] In a feasible embodiment, the sheet resistance of the metal grid 20 provided in the heating area 11 is positively correlated with the length of the heating area 11 in the first direction Y.

[0051] From the above corresponding relationship, it can be seen that when the resistances of the metal grids in each heating area are consistent, the sheet resistance of the metal grid 20 provided in the heating area 11 is positively correlated with the length of the heating area 11 in the first direction Y. Exemplarily, if along the first direction Y, the length of the heating area 11 in the second direction X is increasing, then the sheet resistance of the metal grid 20 in the heating area 11 can be set to increase along the first direction Y to achieve the purpose of making the resistances of the metal grids 20 in each heating area 11 consistent.

[0052] In another feasible embodiment, the sheet resistance of the metal grid 20 provided in the heating area 11 is negatively correlated with the length of the heating area 11 in the second direction X.

[0053] From the above corresponding relationship, it can be seen that when the resistance of the metal grid in each heating area remains the same, the sheet resistance of the metal grid 20 provided in the heating area 11 is negatively correlated with the length of the heating area 11 in the second direction X. Exemplarily, if the length of the heating area 11 in the second direction X increases along the first direction Y, the sheet resistance of the metal grid 20 of the heating area 11 can be set to decrease along the first direction Y to achieve the purpose of keeping the resistance of the metal grid 20 in each heating area 11 the same.

[0054] As a feasible implementation manner, the multiple heating areas include a first heating area and a second heating area, and the metal grid includes a first metal grid provided in the first heating area and a second metal grid provided in the second heating area. The sheet resistance of the first metal grid is less than that of the second metal grid. The grid period of the first metal grid is less than that of the second metal grid, and / or the resistivity of the first metal grid is less than that of the second metal grid, and / or the grid line width of the first metal grid is greater than that of the second metal grid, and / or the thickness of the first metal grid is greater than that of the second metal grid.

[0055] It can be understood that the sheet resistance of the metal grid 20, the grid period of the metal grid 20, the resistivity of the metal grid 20, the grid line width of the metal grid 20, and the thickness of the metal grid 20 satisfy the following corresponding relationship:

[0056]

[0057] Among them, R s represents the sheet resistance of the metal grid 20 provided in the heating area 11, ρ represents the resistivity of the metal grid 20, p represents the grid period of the metal grid 20, t represents the thickness of the metal grid 20, and d represents the grid line width of the metal grid 20. From the above corresponding relationship, it can be seen that the sheet resistance of the metal grid 20 is positively correlated with the grid period of the metal grid 20, the sheet resistance of the metal grid 20 is positively correlated with the resistivity of the metal grid 20, the sheet resistance of the metal grid 20 is negatively correlated with the grid line width of the metal grid 20, and the sheet resistance of the metal grid 20 is negatively correlated with the thickness of the metal grid 20.

[0058] Exemplarily, to make the sheet resistance of the first metal grid less than that of the second metal grid. It can be achieved by setting the grid period of the first metal grid to be less than that of the second metal grid, and / or the resistivity of the first metal grid to be less than that of the second metal grid, and / or the grid line width of the first metal grid to be greater than that of the second metal grid, and / or the thickness of the first metal grid to be greater than that of the second metal grid.

[0059] Exemplarily, in Figure 1 and Figure 2In the illustrated embodiment, along the first direction Y, the length of the heating region 11 in the second direction X increases gradually. To ensure that the resistances of the metal meshes 20 in each heating region 11 are consistent, the sheet resistance of the metal mesh 20 in the heating region 11 can be set to decrease gradually along the first direction Y. To achieve a gradual decrease in the sheet resistance of the metal mesh 20 in the heating region 11 along the first direction Y, the mesh period of the metal mesh 20 in the heating region 11 can be set to decrease gradually along the first direction Y.

[0060] Figure 3 FIG. [ID] is a schematic structural view of another substrate provided by an embodiment of the present invention. Figure 4 FIG. [ID] is a schematic structural view of another heating film provided by an embodiment of the present invention. In Figure 3 and Figure 4 In the illustrated embodiment, along the first direction Y, the length of the heating region 11 in the second direction X first increases and then decreases. To ensure that the resistances of the metal meshes 20 in each heating region 11 are consistent, the sheet resistance of the metal mesh 20 in the heating region 11 can be set to first decrease and then increase along the first direction Y. To achieve a first decrease and then increase in the sheet resistance of the metal mesh 20 in the heating region 11 along the first direction Y, the mesh period of the metal mesh 20 in the heating region 11 can be set to first decrease and then increase along the first direction Y.

[0061] Based on the above embodiments, the plurality of heating regions 11 include a third heating region and a fourth heating region. The metal mesh 20 includes a third metal mesh disposed in the third heating region and a fourth metal mesh disposed in the fourth heating region. The third metal mesh is electrically connected to the fourth metal mesh.

[0062] It should be noted that the metal meshes 20 of the heating regions 11 in the embodiments of the present invention may be insulated from each other along the first direction Y, that is, along the first direction Y, any two adjacent metal meshes are insulated from each other and not electrically connected.

[0063] To reduce the difficulty of the manufacturing process, in the embodiments of the present invention, it may be set that the metal meshes 20 of two adjacent heating regions 11 are electrically connected, or the metal meshes 20 of any two heating regions 11 are electrically connected (as shown in Figure 2 ). Exemplarily, the above-mentioned third heating region and fourth heating region may represent two specific and adjacent heating regions 11, or may represent any two heating regions 11.

[0064] Based on the above embodiments, the plurality of heating regions 11 include a fifth heating region and a sixth heating region. The metal mesh 20 includes a fifth metal mesh disposed in the fifth heating region and a sixth metal mesh disposed in the sixth heating region. The percentage difference P1 between the resistance of the fifth metal mesh and the resistance of the sixth metal mesh satisfies 0% ≤ P1 ≤ 10%.

[0065] Exemplarily, the percentage difference P1 between the resistance of the fifth metal grid and the resistance of the sixth metal grid satisfies the following corresponding relationship:

[0066]

[0067] wherein, R5 is the resistance of the fifth metal grid and R6 is the resistance of the sixth metal grid.

[0068] It should be noted that the fifth heating region and the sixth heating region in the embodiments of the present invention may be two specific heating regions 11. For example, along the first direction Y, the uppermost heating region 11 and the lowermost heating region 11, or any two heating regions 11.

[0069] Based on the above embodiments, the temperature difference K1 between the heating region with the maximum temperature and the heating region with the minimum temperature in the heating film can satisfy 0°C ≤ K1 ≤ 15°C, and the heating uniformity is good.

[0070] Optionally, the grid structure of the metal grid 20 in the embodiments of the present invention may include a square grid, a rhombic grid or a hexagonal grid. The material of the metal grid 20 includes at least one of copper, gold, silver, aluminum and molybdenum. It should be noted that the material of the metal grid 20 will directly affect the grid resistivity of the metal grid 20. Different materials of the metal grid 20 will result in different grid resistivities of the metal grid 20.

[0071] The embodiments of the present invention also provide a preparation method of a heating film for preparing the heating film shown in any of the above embodiments of the present invention. Figure 5 It is a flowchart of a preparation method of a heating film provided by the embodiments of the present invention. Refer to Figure 5 , the preparation method of the heating film in the embodiments of the present invention includes:

[0072] S110. Prepare a substrate, wherein the substrate includes a plurality of heating regions arranged along the first direction.

[0073] Exemplarily, the substrate 10 in the embodiments of the present invention may be a trapezoidal substrate as shown in Figure 1 , or an irregular elliptical substrate as shown in Figure 3 , or other special-shaped substrates. It should be noted that the shape of the substrate 10 in the embodiments of the present invention is not limited and can be set according to the application scenario of the heating film.

[0074] S120. Prepare a metal grid on one side of the substrate, wherein the metal grid is arranged in the heating region, and the sheet resistance of the metal grid is related to the length of the heating region in the first direction and / or the length of the heating region in the second direction, and the first direction intersects with the second direction.

[0075] Exemplarily, the first direction and the second direction may be perpendicular to each other. Refer to Figure 2 and Figure 4 , one of screen printing, imprinting and scraping coating, inkjet printing, electrohydrodynamic printing, photolithography, and metal etching process technologies can be used to prepare the metal grid 20 on one side of the substrate 10. By setting different voltages applied to the first electrode 30 and the second electrode 40, a current can pass through the metal grid 20 disposed in the heating region 11 and electrically connected to the first electrode 30 and the second electrode 40. When the current passes through the metal grid 20, heat is generated, thereby realizing the electrothermal function of the heating film.

[0076] S130. Prepare the first electrode and the second electrode, wherein the first electrode and the second electrode are respectively located on two opposite sides of the substrate along the second direction, and both the first electrode and the second electrode are electrically connected to the metal grid.

[0077] Exemplarily, refer to Figure 2 and Figure 4 , sputtering, evaporation, electroplating, etc. can be used to prepare the first electrode 30 and the second electrode 40. By setting different voltages applied to the first electrode 30 and the second electrode 40, a current can pass through the metal grid 20 disposed in the heating region 11 and electrically connected to the first electrode 30 and the second electrode 40. When the current passes through the metal grid 20, heat is generated, thereby realizing the electrothermal function of the heating film.

[0078] In the heating film prepared by the above preparation method according to the embodiment of the present invention, the sheet resistance of the metal grid 20 located in the heating region 11 is related to the length of the heating region 11 in the first direction Y and / or the length of the heating region 11 in the second direction X. The sheet resistance of the metal grid 20 in each heating region 11 can be set according to the length of each heating region 11 in the first direction Y and / or the length of each heating region 11 in the second direction X, so as to make the resistances of the metal grids 20 in each heating region 11 consistent, which is beneficial to improving the heating uniformity of the heating film.

[0079] Figure 6 It is a flowchart of another preparation method of the heating film provided by the embodiment of the present invention. Figure 6 The illustrated embodiment details how to prepare the metal grid on one side of the substrate. Refer to Figure 6 , the preparation method of the heating film in the embodiment of the present invention includes:

[0080] S210. Prepare the substrate, wherein the substrate includes a plurality of heating regions arranged along the first direction.

[0081] S220. Determine the preset resistance of the heating film according to the preset heating power, preset heating temperature, preset driving voltage, and preset heating uniformity requirement.

[0082] It should be noted that with reference to Figure 2 and Figure 4 , in the embodiments of the present invention, it is exemplified that the metal grids 20 of any two heating regions 11 in the heating film are electrically connected, that is, the metal grids 20 in the heating film are integrally arranged. At this time, the preset resistance of the heating film obtained according to the above step S220 refers to the resistance of the integrally arranged metal grids 20 in the heating film.

[0083] S230. Determine the preset regional resistance of the heating region according to the preset resistance and the preset number of heating regions.

[0084] Exemplarily, with reference to Figure 2 and Figure 4 , in order to improve the heating uniformity of the heating film, the resistances of the metal grids of each heating region in the embodiments of the present invention need to be kept consistent. When the resistances of the metal grids 20 arranged in each heating region 11 are equal, the preset regional resistance of the heating region can be determined according to the following corresponding relationship:

[0085] R y = R z × m.

[0086] Wherein, R z is the preset resistance of the heating film, R y is the preset regional resistance of the heating region, and m is the preset number of heating regions.

[0087] When the preset number of heating regions 11 is determined, the distribution of the heating regions 11 can be determined, and the lengths of the heating regions 11 in the first direction Y can be set to be the same, as shown in Figure 1 and Figure 3 .

[0088] It should be noted that the embodiments of the present invention do not limit the preset number of heating regions 11, and those skilled in the art can set it according to actual situations. It can be understood that the larger the preset number of heating regions 11, the more beneficial it is to the heating uniformity of the entire heating film, and the preset number of heating regions 11 is generally greater than or equal to 7.

[0089] S240. Determine the theoretical data of the metal grids of each heating region according to the preset regional resistance, the length of the heating region in the first direction, and the length of the heating region in the second direction. The theoretical data includes at least one of the theoretical grid line width, the theoretical grid period, the theoretical grid thickness, and the theoretical grid resistivity.

[0090] Exemplarily, with reference to Figure 2 and Figure 4, after determining the preset regional resistance of the heating region 11, the theoretical data of the metal grid 20 of each heating region 11 can be determined according to the preset regional resistance, the length of the heating region 11 in the first direction Y, and the length of the heating region 11 in the second direction X, so that the resistance of the metal grid 20 of each heating region 11 is consistent.

[0091] S250. Simulate and analyze the heating performance of the heating film according to the theoretical data and the simulation software to obtain the simulation analysis result.

[0092] Exemplarily, referring to Figure 2 and Figure 4 , the theoretical data of the metal grid 20 of each heating region 11 in the embodiments of the present invention may include the theoretical grid line width, theoretical grid period, theoretical grid thickness, and theoretical grid resistivity of the metal grid 20 of each heating region 11. The theoretical grid line width, theoretical grid period, theoretical grid thickness, and theoretical grid resistivity of the metal grid 20 of each heating region 11 can be input into the comsol simulation software to simulate and analyze the electric field distribution and heating performance of the heating region 11. To further improve the accuracy of the simulation analysis, the grid structure of the metal grid 20 of each heating region 11 can also be added to the comsol simulation software. The grid structure of the metal grid 20 may include a square grid, a rhombic grid, or a hexagonal grid. The simulation analysis result in the embodiments of the present invention may include temperature distribution information and electric field distribution information.

[0093] S260. Adjust the theoretical data according to the simulation analysis result until the simulation analysis result meets the preset requirements, and prepare a metal grid on one side of the substrate according to the adjusted theoretical data, wherein the metal grid is arranged in the heating region, and the sheet resistance of the metal grid is related to the length of the heating region in the first direction and / or the length of the heating region in the second direction, and the first direction intersects with the second direction.

[0094] Exemplarily, referring to Figure 2 and Figure 4 , if it is determined according to the temperature distribution information that the electric field distribution uniformity of the heating film does not meet the first preset requirement, or it is determined according to the electric field distribution information that the heating uniformity of the heating film does not meet the second preset requirement, it is necessary to adjust the theoretical data of the metal grid 20 of each heating region 11, or adjust the grid structure of the metal grid 20 of each heating region 11 until the electric field distribution uniformity of the heating film meets the first preset requirement and the heating uniformity of the heating film meets the second preset requirement.

[0095] For example Figure 1 and Figure 2 As shown in Figure 1The trapezoidal structure shown (upper base 11 cm, lower base 17 cm, height 9 cm). Then, according to heating requirements such as a preset heating power (e.g., power density ≤ 1000 W / m2), a preset heating temperature, a preset driving voltage (e.g., 10 V), and a preset heating uniformity (e.g., heating uniformity below 10 °C), the trapezoidal region is divided into 7 heating regions 11. Each heating region 11 is filled with a square structure. The mesh period of the metal mesh 20 of the heating regions 11 is set to gradually decrease along the first direction Y, decreasing by 0.55 times from the uppermost heating region 11 to the lowermost heating region 11. The line width is set to 3 μm, so that the resistance of the metal mesh 20 set in each heating region 11 remains consistent. Then, the electric field distribution and heating performance of the heating film shown in Figure 2 are simulated using Comsol simulation software to achieve a heating effect that meets the requirements. Finally, a grid structure of the required heating pattern is formed on a PET (polyethylene terephthalate) flexible substrate using imprinting and scraping coating methods, obtaining a highly transparent and uniform heating effect, with a light transmittance greater than 85% and a temperature difference in the heating region less than 10 °C.

[0096] As Figure 3 and Figure 4 shown, taking an irregular elliptical substrate as an example, first determine the heating region according to the position of the automotive window radar antenna, which is an elliptical structure shown in Figure 3 (the diameter of the semi-circle at the edge is 10 cm, and the side length of the middle rectangle is 10 cm). Then, according to heating requirements such as a preset heating power (e.g., power density ≤ 1000 W / m2), a preset heating temperature, a preset driving voltage (e.g., 20 V), and a preset heating uniformity (e.g., heating uniformity below 10 °C), the trapezoidal region is divided into 12 heating regions 11. Each heating region 11 is filled with a square structure. The mesh period of the metal mesh 20 of the first heating region to the twelfth heating region set along the first direction Y first gradually decreases and then gradually increases. Specifically, the mesh period of the metal mesh 20 from the uppermost first heating region to the sixth heating region decreases by 0.17 times step by step, and the line width is set to 3 μm; the mesh period of the metal mesh 20 from the lowermost twelfth heating region to the seventh heating region decreases by 0.17 times step by step, and the line width is set to 3 μm. The mesh period of the metal mesh 20 of the uppermost first heating region is the same as that of the lowermost twelfth heating region, so that the resistance of the metal mesh 20 set in each heating region 11 remains consistent. Then, the electric field distribution and heating performance of the heating film shown in Figure 4 are simulated using Comsol simulation software to achieve a heating effect that meets the requirements. Finally, a grid structure of the required heating pattern is formed on a PMMA (polymethyl methacrylate) flexible substrate using lithography and metal etching techniques, obtaining a highly transparent and uniform heating effect, with a light transmittance greater than 82% and a temperature in the heating region less than 8 °C.

[0097] S270. Prepare a first electrode and a second electrode, wherein the first electrode and the second electrode are respectively located on two opposite sides of the substrate along a second direction, and both the first electrode and the second electrode are electrically connected to a metal grid.

[0098] Based on the same inventive concept, an embodiment of the present invention further provides a heating glass, which includes the heating film shown in any one of the above embodiments of the present invention.

[0099] The heating glass in the embodiment of the present invention includes the heating film provided in any one of the above embodiments of the present invention. Therefore, the heating glass includes the technical features of the heating film and has the beneficial effects of the heating film. The same parts can be referred to the above description.

[0100] It should be noted that such a design method is applicable to the heating and defogging of the lidar antenna area of the car window, also applicable to the heating and defogging of the car headlight, and simultaneously applicable to the heating and defogging of the aircraft windshield.

[0101] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub - combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A heating film, characterized in that, It includes a substrate, a metal grid, a first electrode, and a second electrode; The substrate includes a plurality of heating regions arranged in a first direction; The metal grid is located on one side of the substrate, and the metal grid is disposed in the heating regions; The first electrode and the second electrode are respectively located on two opposite sides of the substrate along a second direction, and both the first electrode and the second electrode are electrically connected to the metal grid, and the first direction intersects with the second direction; Wherein, the sheet resistance of the metal grid disposed in the heating region is related to the length of the heating region in the first direction and / or the length of the heating region in the second direction.

2. The heating film according to claim 1, wherein The sheet resistance of the metal grid disposed in the heating region is positively correlated with the length of the heating region in the first direction.

3. The heating film according to claim 1, characterized in that, The sheet resistance of the metal grid disposed in the heating region is negatively correlated with the length of the heating region in the second direction.

4. The heating film according to claim 1, wherein The plurality of heating regions include a first heating region and a second heating region, and the metal grid includes a first metal grid disposed in the first heating region and a second metal grid disposed in the second heating region; The sheet resistance of the first metal grid is less than that of the second metal grid; The grid period of the first metal grid is less than that of the second metal grid, and / or, the resistivity of the first metal grid is less than that of the second metal grid, and / or, the grid line width of the first metal grid is greater than that of the second metal grid, and / or, the thickness of the first metal grid is greater than that of the second metal grid.

5. The heating film according to claim 1, characterized in that, The plurality of heating regions include a third heating region and a fourth heating region, and the metal grid includes a third metal grid disposed in the third heating region and a fourth metal grid disposed in the fourth heating region; The third metal grid is electrically connected to the fourth metal grid.

6. The heating film according to claim 1, wherein The plurality of heating regions include a fifth heating region and a sixth heating region, and the metal grid includes a fifth metal grid disposed in the fifth heating region and a sixth metal grid disposed in the sixth heating region; The percentage difference P1 between the resistance of the fifth metal grid and the resistance of the sixth metal grid satisfies 0% ≤ P1 ≤ 10%.

7. The heating film according to claim 1, characterized in that, The temperature difference K1 between the heating region with the maximum temperature and the heating region with the minimum temperature satisfies 0°C ≤ K1 ≤ 15°C.

8. A method for preparing a heating film, which is used to prepare the heating film according to any one of claims 1-7, characterized in that, The preparation method includes: Preparing a substrate, wherein the substrate includes a plurality of heating regions arranged in a first direction; Preparing a metal grid on one side of the substrate, wherein the metal grid is disposed in the heating regions, the sheet resistance of the metal grid is related to the length of the heating region in the first direction and / or the length of the heating region in the second direction, and the first direction intersects with the second direction; Preparing a first electrode and a second electrode, wherein the first electrode and the second electrode are respectively located on two opposite sides of the substrate along the second direction, and both the first electrode and the second electrode are electrically connected to the metal grid.

9. The preparation method according to claim 8, characterized in that, Preparing a metal grid on one side of the substrate includes: Determine the preset resistance of the heating film according to the preset heating power, preset heating temperature, preset driving voltage, and preset heating uniformity requirement; Determine the preset regional resistance of the heating region according to the preset resistance and the preset number of the heating regions; Determine the theoretical data of the metal grid of each heating region according to the preset regional resistance, the length of the heating region in the first direction, and the length of the heating region in the second direction, where the theoretical data includes at least one of theoretical grid line width, theoretical grid period, theoretical grid thickness, and theoretical grid resistivity; Conduct simulation analysis on the heating performance of the heating film according to the theoretical data and simulation software to obtain a simulation analysis result; Adjust the theoretical data according to the simulation analysis result until the simulation analysis result meets the preset requirements, and fabricate the metal grid on one side of the substrate according to the adjusted theoretical data.

10. A heated glass, characterized in that, Include the heating film according to any one of claims 1-7.

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