Preparation method of transfer mold, imprinting mold, cover plate, preparation method of cover plate and terminal

Abstract

The invention provides a preparation method of a transfer mold, an imprinting mold, a cover plate, a preparation method and a terminal. The preparation method of the transfer printing mold comprises the steps that a metal plate is provided; performing first anodic oxidation on the metal plate to form a porous structure on the surface of the metal plate; carrying out chemical etching on the metal plate to remove the porous structure, so that a plurality of nano pits which are distributed at intervals are formed in the surface of the metal plate; carrying out second anodic oxidation on the metal plate so as to carry out pore forming; the metal plate is subjected to chambering to obtain a transfer printing mold, the transfer printing mold comprises a plurality of first sunken parts arranged on the surface of the transfer printing mold at intervals, and the range of the arrangement period d1 of the first sunken parts is d1 smaller than or equal to 200 nm. According to the preparation method of the transfer printing mold, the prepared transfer printing mold can be used for preparing a cover plate, and the prepared cover plate has relatively high light transmittance and relatively low reflective rate.

Description

Technical Field

[0001] This application relates to the field of electronics, specifically to a method for preparing a transfer mold, an embossing mold, a cover plate and its preparation method, and a terminal. Background Technology

[0002] To extend the lifespan of displays in mobile phones and other devices, protective covers are typically installed on the display surface to improve the screen's resistance to impacts and drops. However, existing protective covers have high reflectivity and insufficient transmittance, affecting the display quality of the device. Summary of the Invention

[0003] This application provides a method for preparing a transfer mold, which can be used to prepare a cover plate. The prepared cover plate has high light transmittance and low reflectivity.

[0004] In a first aspect, embodiments of this application provide a method for preparing a transfer mold, the method comprising:

[0005] Metal sheets are provided;

[0006] The metal plate is subjected to a first anodizing process to form a porous structure on the surface of the metal plate.

[0007] The metal plate is chemically etched to remove the porous structure, thereby forming multiple nano-pits spaced apart on the surface of the metal plate.

[0008] The metal plate is subjected to a second anodizing to create pores; and

[0009] The metal plate is enlarged to obtain a transfer mold, wherein the transfer mold includes a plurality of first recesses spaced apart on its surface, and the arrangement period d1 of the plurality of first recesses is in the range of d1≤200nm.

[0010] Secondly, embodiments of this application also provide an imprinting mold, which is obtained by two transfers using the method for preparing a transfer mold described in the first aspect of this application. The imprinting mold includes a plurality of second recesses spaced apart on its surface. The plurality of first recesses have the same structure as the plurality of second recesses. The arrangement period d2 of the plurality of second recesses is in the range of d2≤200nm. The width a2 of the second recesses is in the range of 40nm≤a2≤200nm. The depth h2 of the second recesses is in the range of 100nm≤h2≤500nm.

[0011] Thirdly, embodiments of this application also provide a method for preparing a cover plate, the method comprising:

[0012] Provide base materials;

[0013] A photoresist layer is formed on the surface of the substrate;

[0014] A textured structure is imprinted on the surface of the photoresist layer using the imprinting mold described in the second aspect of this application, wherein the textured structure is complementary to the structure of the plurality of second recesses of the imprinting mold; and

[0015] Dry etching is performed to obtain a cover plate, wherein the cover plate includes a plurality of protrusions spaced apart on its surface, the arrangement period d3 of the plurality of protrusions being in the range of d3≤200nm, and the plurality of protrusions being structurally complementary to the plurality of second recesses of the imprinting mold.

[0016] Fourthly, embodiments of this application also provide a cover plate, the cover plate comprising: a plurality of protrusions spaced apart on its surface, wherein the arrangement period d3 of the plurality of protrusions is in the range of: d3≤200nm.

[0017] Fifthly, embodiments of this application also provide a terminal, which includes:

[0018] The display screen has a display surface;

[0019] The cover plate described in the fourth aspect embodiment of this application is stacked on the display surface of the display screen to protect the display screen; and

[0020] A processor, electrically connected to the display screen, is used to control the display screen to perform a display.

[0021] The method for preparing the transfer mold according to this application involves sequentially performing a first anodizing, chemical etching, a second anodizing, and hole enlargement process on a metal plate to obtain the transfer mold. This method is applicable not only to the preparation of small-sized transfer molds but also to the preparation of large-sized transfer molds (e.g., larger than 8 inches). Furthermore, the preparation cost of the transfer mold using this method is low, thereby reducing the preparation cost of the cover plate made using this transfer mold. Moreover, the size of the first recess in the transfer mold prepared by this method is easily adjustable and controlled. By ensuring that the arrangement period of the first recess is less than or equal to 200 nm, the arrangement period of the protrusions in the cover plate made using the transfer mold can also be less than or equal to 200 nm, thereby significantly reducing the reflectivity and increasing the transmittance of the cover plate. When the cover plate is applied to a terminal to protect the terminal's display screen, it can provide the terminal with better display performance. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a cross-sectional structural schematic diagram of a transfer mold according to an embodiment of this application.

[0024] Figure 2 This is a scanning electron microscope image of the transfer mold of Embodiment 6 of this application.

[0025] Figure 3 This is a schematic flowchart of a method for preparing a transfer mold according to an embodiment of this application.

[0026] Figure 4 This is a scanning electron microscope image of a porous metal plate after first anodizing, as described in Embodiment 6 of this application.

[0027] Figure 5 This is another scanning electron microscope image of the porous metal plate after the first anodizing of Embodiment 6 of this application.

[0028] Figure 6 This is a scanning electron microscope image of a metal plate with multiple nano-pits after chemical etching, as described in Example 6 of this application.

[0029] Figure 7 This is a schematic diagram of the structure of an embossing mold according to an embodiment of this application.

[0030] Figure 8 This is a schematic flowchart of a method for preparing a cover plate according to an embodiment of this application.

[0031] Figure 9 This is a schematic diagram of the structure of a cover plate according to an embodiment of this application.

[0032] Figure 10 This is a cover plate edge according to an embodiment of this application. Figure 9 A schematic diagram of the cross-sectional structure along the AA direction.

[0033] Figure 11 This is a schematic diagram of the structure of a terminal according to an embodiment of this application.

[0034] Figure 12 This is a partial exploded structural diagram of a terminal according to an embodiment of this application.

[0035] Figure 13 This is a circuit block diagram of a terminal according to an embodiment of this application.

[0036] Explanation of reference numerals in the attached figures:

[0037] 200-Transfer mold, 210-First recessed part, 300-Imprinting mold, 310-Second recessed part, 500-Cover plate, 510-Protrusion, 520-Cover body part, 600-Terminal, 610-Display screen, 611-Display surface, 620-Middle frame, 630-Processor, 640-Housing, 641-Light-transmitting part, 650-Memory, 670-Camera module. Detailed Implementation

[0038] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0039] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0040] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0041] It should be noted that, for ease of explanation, the same reference numerals denote the same components in the embodiments of this application, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments.

[0042] To extend the lifespan of displays in mobile phones and other devices, protective covers are typically installed on the display surface to improve the screen's resistance to impacts and drops. However, existing protective covers have high reflectivity and insufficient transmittance, affecting the display quality of the device.

[0043] Figure 1 This is a schematic diagram of the structure of a transfer mold 200 according to an embodiment of this application. Figure 2 This is a scanning electron microscope image of the transfer mold 200 of Embodiment 6 of this application. Figure 3 This is a schematic flowchart of a method for preparing a transfer mold 200 according to an embodiment of this application.

[0044] Please see Figures 1 to 3This application provides a method for preparing a transfer mold 200, the method comprising:

[0045] S101, provided with metal sheet;

[0046] Optionally, the metal plate may be, but is not limited to, an aluminum plate or aluminum sheet. For better illustration of the technical solution of this application, the metal plate will be described using aluminum foil as an example in the following description, and should not be construed as a limitation on the metal plate used in this application.

[0047] Optionally, the purity of the metal plate can be, but is not limited to, 99.999% (abbreviated as 5N). In one specific embodiment, the metal plate is an aluminum foil with a purity of 99.999% and a thickness of 0.2 mm.

[0048] Optionally, the thickness of the metal sheet ranges from 0.15 mm to 0.5 mm. Specifically, the thickness of the metal sheet can be, but is not limited to, 0.15 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc.

[0049] S102, the metal plate is subjected to a first anodizing (also known as pre-anodizing) to form a porous structure on the surface of the metal plate;

[0050] S103, chemically etch the metal plate to remove the porous structure, so that multiple nano-pits are formed on the surface of the metal plate.

[0051] S104, the metal plate is subjected to a second anodizing to create holes; and

[0052] S105, the metal plate is enlarged to obtain a transfer mold 200, wherein the transfer mold 200 includes a plurality of first recesses 210 spaced apart on its surface, and the arrangement period d1 of the plurality of first recesses 210 is in the range of d1≤200nm.

[0053] In this application, the term "multiple" means two or more.

[0054] The transfer mold 200 prepared by the method of this application embodiment can be used to prepare a cover plate. Specifically, the transfer mold 200 is transferred twice to obtain an imprinting mold, so that the imprinting mold has a plurality of second recesses with the same structure as the first recesses 210. A photoresist layer is formed on the substrate, and a texture structure is formed on the photoresist layer using the imprinting mold, followed by dry etching to obtain a cover plate. The obtained cover plate has a plurality of protrusions on its surface, and the structures of the plurality of protrusions are complementary to those of the plurality of second recesses. It can be understood that the structures of the plurality of protrusions are also complementary to those of the plurality of first recesses 210. In this application, by directly forming the plurality of protrusions on the cover plate, that is, by making the plurality of protrusions an integral structure with the substrate of the cover plate, the plurality of protrusions are not easily detached. By controlling the size of the first recess 210, the size of the protrusion of the cover plate can be controlled, so that the arrangement period of the protrusion of the cover plate is less than or equal to 200nm, thereby greatly reducing the reflectivity of the cover plate and increasing the transmittance of the cover plate.

[0055] It should be noted that, unless otherwise specified, "reflectivity" in this application refers to visible light reflectivity and "transmittance" refers to visible light transmittance.

[0056] Optionally, the first recess 210 may have a parabolic, triangular, spindle-shaped, serrated, or inverted conical structure. That is, after being cut along a direction perpendicular to the thickness of the transfer mold 200, the first recess 210 may have a parabolic, triangular, spindle-shaped, serrated, or inverted conical structure. Multiple first recesses 210 are spaced apart on the surface of the transfer mold 200.

[0057] Optionally, the arrangement period d1 of the plurality of first recesses 210 is in the range of 50nm ≤ d1 ≤ 200nm. Specifically, the arrangement period d1 of the plurality of first recesses 210 can be, but is not limited to, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, 180nm, 190nm, 200nm, etc. If the arrangement period d1 of the plurality of first recesses 210 on the transfer mold 200 is too small, it increases the difficulty of manufacturing the transfer mold 200; if the arrangement period d1 of the plurality of first recesses 210 on the transfer mold 200 is too large, when the transfer mold 200 is used to manufacture a cover plate, the arrangement period of the protrusions on the cover plate is too large, which easily forms Mie scattering, thereby reducing the transparency of the cover plate.

[0058] The method for preparing the transfer mold 200 according to this application involves sequentially performing a first anodizing, chemical etching, a second anodizing, and hole enlargement process on a metal plate to obtain the transfer mold 200. This method is applicable not only to the preparation of small-sized transfer molds 200 but also to the preparation of large-sized (e.g., larger than 8 inches) transfer molds 200. Furthermore, the preparation cost of the transfer mold 200 using this method is low, thereby reducing the preparation cost of the cover plate made using this transfer mold 200. Moreover, the size of the first recess 210 of the transfer mold 200 prepared by this method is easily adjustable and controlled. By making the arrangement period of the first recess 210 less than or equal to 200 nm, the arrangement period of the protrusions of the cover plate made using the transfer mold 200 can be made less than or equal to 200 nm, thereby significantly reducing the reflectivity and increasing the transmittance of the cover plate. When the cover plate is applied to a terminal to protect the terminal's display screen, the terminal can have a better display effect.

[0059] In some embodiments, in S101, providing the metal plate includes:

[0060] The metal plate is electrochemically polished to reduce its surface roughness to less than or equal to 5 nm. The surface of the metal plate (e.g., aluminum foil) typically forms an oxide film (e.g., aluminum oxide film). Electrochemical polishing of the metal plate before the first anodizing removes surface defects, reduces defects in the resulting transfer mold 200, and thus better reduces defects in the resulting cover plate, improving the appearance yield of the cover plate and giving it better anti-reflective and anti-transparency effects.

[0061] Optionally, a metal plate (e.g., aluminum foil) is immersed in a solution of ethanol and perchloric acid (i.e., an ethanol solution of perchloric acid) and electrochemically polished at a solution temperature of -3°C to 3°C and a voltage of 18V to 22V until the surface roughness of the metal plate is less than or equal to 5nm, for a polishing time of 2min to 6min.

[0062] In the embodiments of this application, when the numerical range a to b is involved, unless otherwise specified, the numerical value can be any value between a and b, including the endpoint value a and the endpoint value b.

[0063] In one specific embodiment, the metal plate is aluminum foil. During electrochemical polishing, the aluminum foil is used as the anode and the lead plate (Pb plate) is used as the cathode. The metal plate is placed in a solution composed of ethanol and perchloric acid to carry out an electrochemical reaction.

[0064] Optionally, the volume ratio of ethanol to perchloric acid in the solution is 3:1 to 6:1. Specifically, the volume ratio of ethanol to perchloric acid in the solution can be, but is not limited to, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, etc. If the volume ratio of ethanol to perchloric acid is too high, the concentration of perchloric acid will be too low, reducing the effect of electrochemical polishing. This results in excessive surface roughness of the metal plate after electrochemical polishing, leading to more defects in the resulting transfer mold 200. These defects can easily transfer to the cover plate, reducing the appearance yield and transparency of the cover plate, and also reducing the precision of the protrusions on the cover plate, affecting the anti-reflective and anti-transparency effects of the cover plate. If the volume ratio of ethanol to perchloric acid is too low, the concentration of perchloric acid will be too high, which can easily lead to an explosion during the electrochemical process, affecting the safety of the preparation of the transfer mold 200.

[0065] Optionally, the voltage for electrochemical polishing can be, but is not limited to, 18V, 19V, 20V, 21V, 22V, etc. If the voltage for electrochemical polishing is too low, the polishing speed will be too low, reducing the preparation efficiency of the transfer mold 200; if the voltage for electrochemical polishing is too high, it will easily affect the polishing quality, resulting in the surface roughness of the metal plate after electrochemical polishing still being too large, increasing the defects of the obtained transfer mold 200.

[0066] Optionally, the electrochemical polishing temperature (i.e., the temperature of the ethanol and perchloric acid solution) can be, but is not limited to, -3℃, -2℃, -1℃, 0℃, 1℃, 2℃, 3℃, etc. If the electrochemical polishing temperature is too low, the polishing speed will be too low, reducing the preparation efficiency of the transfer mold 200; if the electrochemical polishing temperature is too high, it will easily affect the polishing quality, resulting in an excessively rough surface on the metal plate after electrochemical polishing, increasing the defects of the obtained transfer mold 200.

[0067] Optionally, the electrochemical polishing time can be, but is not limited to, 2 min, 3 min, 4 min, 5 min, 6 min, etc. If the electrochemical polishing time is too short, the roughness of the metal plate will be too large, resulting in more defects in the obtained transfer mold 200. These defects are easily transferred to the cover plate, reducing the appearance yield and transparency of the cover plate, and also reducing the precision of the protrusions on the cover plate, affecting the anti-reflection and anti-transparency effects of the cover plate. If the electrochemical polishing time is too long, the metal plate is prone to orange peel phenomenon, which also increases the defects in the obtained transfer mold 200.

[0068] Optionally, before electrochemical polishing, the preparation method further includes: ultrasonically cleaning the metal plate with acetone and deionized water respectively, drying it, and then mechanically polishing it.

[0069] Optionally, the acetone cleaning and deionized water cleaning times are both 2 to 5 minutes (e.g., but not limited to 2 minutes, 3 minutes, 4 minutes, 5 minutes, etc.).

[0070] Mechanical polishing can be done using a wool wheel until the surface is free of scratches and has a glossy finish.

[0071] In some embodiments, S102, the first anodizing of the metal plate to form a porous structure on the surface of the metal plate includes:

[0072] The metal plate is subjected to a first anodic oxidation in a first electrolyte to form a porous structure on the surface of the metal plate. The first electrolyte comprises: 0.015 mol / L to 0.05 mol / L sulfuric acid, 0.1 mol / L to 0.5 mol / L oxalic acid, and 0.1 g / L to 1 g / L aluminum sulfate.

[0073] Optionally, the porous structure is a columnar pore structure. After the first anodizing, the porous structure is relatively disordered. It should be noted that after the first anodizing, the top (i.e., the part near the surface) of the porous structure formed on the surface of the metal plate is disordered, but the root or bottom (i.e., the bottom of the pores) of the porous structure is relatively ordered and has a relatively uniform structure. That is, the size, arrangement period, etc. of the bottom of the porous structure are relatively uniform.

[0074] Optionally, during the first anodizing, aluminum foil is used as the anode and a lead plate (Pb plate) is used as the cathode.

[0075] In this embodiment, a first electrolyte is used to perform the first anodizing on a metal plate (taking aluminum foil as an example). The first electrolyte includes sulfuric acid, oxalic acid, and aluminum sulfate. During the first anodizing of the metal plate, such as aluminum foil, a relatively hard barrier layer (such as a hard γ-alumina layer) first forms on the surface of the aluminum foil. Then, aluminum oxide is dissolved and generated simultaneously, finally forming a porous alumina layer with a porous structure. In this embodiment, sulfuric acid plays a conductive electrolytic role in the first electrolyte, dissolving the aluminum foil at the anode and forming an oxide film at the anode. Oxalic acid inhibits the dissolution of the aluminum anode, thereby allowing a denser oxide film to form on the surface of the aluminum foil. Aluminum sulfate provides aluminum ions (Al... 3+ This makes the first anodizing of the aluminum foil surface more uniform.

[0076] It should be noted that the first electrolyte is an aqueous solution of sulfuric acid, oxalic acid and aluminum sulfate, that is, the solvent is water.

[0077] Specifically, the concentration of sulfuric acid in the first electrolyte can be, but is not limited to, 0.015 mol / L, 0.018 mol / L, 0.02 mol / L, 0.025 mol / L, 0.03 mol / L, 0.035 mol / L, 0.04 mol / L, 0.045 mol / L, 0.05 mol / L, etc. If the concentration of sulfuric acid in the first electrolyte is too low, the dissolution rate of the alumina film on the aluminum foil surface will be too slow, and the pore size of the porous structure formed on the metal plate surface will be too small, resulting in an insignificant anti-reflective and anti-reflective effect on the cover plate made using the transfer mold 200. If the concentration of sulfuric acid in the first electrolyte is too high, the dissolution rate of the alumina film will be too fast, and the pore size of the porous structure formed on the metal plate will be too large, resulting in an excessively large pore size in the transfer mold 200. This will cause the cover plate made using the transfer mold 200 to be prone to fogging or iridescent phenomena, affecting the appearance of the cover plate.

[0078] Specifically, the concentration of oxalic acid in the first electrolyte can be, but is not limited to, 0.1 mol / L, 0.15 mol / L, 0.18 mol / L, 0.2 mol / L, 0.25 mol / L, 0.3 mol / L, 0.35 mol / L, 0.4 mol / L, 0.45 mol / L, 0.5 mol / L, etc. If the concentration of oxalic acid in the first electrolyte is too low, a high-quality oxide film cannot be formed on the surface of the metal plate, resulting in a rough surface of the transfer mold 200 and a tendency for pitting. When this transfer mold 200 is used to prepare a cover plate, it can easily cause pitting on the surface of the cover plate, affecting its appearance. If the concentration of oxalic acid in the first electrolyte is too high, the hardness of the oxide film on the surface of the metal plate decreases, reducing the service life of the transfer mold 200. In addition, if the concentration of oxalic acid in the first electrolyte is too high, it will reduce the stability of the first electrolyte, making it more susceptible to impurities. This will affect the structure of the first recess 210 of the transfer mold 200, thus affecting the anti-reflective and anti-transparency effects of the cover plate made by the transfer mold 200.

[0079] Specifically, the concentration of aluminum sulfate in the first electrolyte can be, but is not limited to, 0.1 g / L, 0.2 g / L, 0.3 g / L, 0.4 g / L, 0.5 g / L, 0.6 g / L, 0.7 g / L, 0.8 g / L, 0.9 g / L, 1.0 g / L, etc. If the concentration of aluminum sulfate in the first electrolyte is too low, the thickness of the oxide film on the surface of the metal plate (the thickness of the aluminum oxide film formed on the surface of the aluminum foil is about 0.5 μm to 2 μm) will be too thin, and the first recess 210 of the transfer mold 200 will not be able to achieve the preset size structure. If the concentration of aluminum sulfate in the first electrolyte is too high, it will affect the growth rate and uniformity of the oxide film on the surface of the metal plate. Uneven oxide film growth will affect the uniformity of the porous structure on the metal plate, thereby affecting the size uniformity of the multiple first recesses 210 of the obtained transfer mold 200.

[0080] In some embodiments, S102, the step of performing a first anodic oxidation on the metal plate in a first electrolyte to form a porous structure on the surface of the metal plate includes:

[0081] The metal plate is immersed in a first electrolyte, wherein the first temperature T1 of the first electrolyte is in the range of -3℃ ≤ T1 ≤ 3℃; and

[0082] Under a first voltage U1 of 60V≤U1≤120V, a first anodizing is performed to form a porous structure on the surface of the metal plate.

[0083] Scanning electron microscope (SEM) image of the porous metal plate after the first anodizing process is shown below. Figure 4 and Figure 5 As shown. By Figure 4 and Figure 5 It can be seen that after the first anodizing, the top (i.e., the part near the surface) of the porous structure formed on the surface of the metal plate is disordered, but the root or bottom (i.e., the bottom of the pores) of the porous structure is more ordered and has a relatively uniform structure. That is, the size, arrangement period, etc. of the bottom of the porous structure are relatively uniform.

[0084] Specifically, the first temperature T1 of the first electrolyte (i.e., the temperature of the first anodizing) can be, but is not limited to, -3℃, -2℃, -1℃, 0℃, 1℃, 2℃, 3℃, etc. If the first temperature T1 of the first electrolyte is too low, the pore size of the porous structure formed on the surface of the metal plate will be too small, resulting in an insignificant anti-reflective effect on the cover plate made using the transfer mold 200. If the first temperature T1 of the first electrolyte is too high, the pore size of the porous structure formed on the metal plate will be too large, resulting in an excessively large pore size in the transfer mold 200. This will cause the cover plate made using the transfer mold 200 to be prone to fogging or iridescent phenomena, affecting the appearance of the cover plate. In addition, it will easily cause the size of the porous structure of the metal plate to be uneven, affecting the uniformity of the size of the multiple first recesses 210 on the transfer mold 200.

[0085] Specifically, the first voltage U1 (i.e., the voltage of the first anodizing) can be, but is not limited to, 60V, 70V, 80V, 90V, 100V, 110V, 120V, etc. If the first voltage U1 is too low, the pore size of the porous structure formed on the surface of the metal plate will be too small, resulting in an insignificant anti-reflective effect on the cover plate made using the transfer mold 200. If the first voltage U1 is too high, the pore size of the porous structure formed on the metal plate will be too large, resulting in an excessively large pore size in the transfer mold 200. This will cause the cover plate made using the transfer mold 200 to be prone to fogging or iridescent phenomena, affecting the appearance of the cover plate. In addition, it will easily cause the size of the porous structure of the metal plate to be uneven, affecting the uniformity of the size of the multiple first recesses 210 on the transfer mold 200.

[0086] Optionally, the first anodizing time is 1 hour to 1.5 hours. Specifically, the first anodizing time can be, but is not limited to, 1 hour, 65 minutes, 70 minutes, 75 minutes, 80 minutes, 85 minutes, 90 minutes, etc. If the first anodizing time is too short, the formed porous structure cannot reach the preset size, causing the size of the multiple first recesses 210 on the transfer mold 200 to not reach the expected size; if the first anodizing time is too long, it will affect the uniformity of the porous structure on the metal plate surface, and thus affect the uniformity of the size of the multiple first recesses 210 on the transfer mold 200.

[0087] In some embodiments, in S103, the chemical etching of the metal plate to remove the porous structure, resulting in a plurality of spaced-apart nano-pits on the surface of the metal plate, includes:

[0088] The metal plate is immersed in a first etching solution for chemical etching to remove the porous structure, resulting in multiple nano-pits on the surface of the metal plate. The first etching solution comprises 4% to 10% phosphoric acid, 1% to 3% chromic acid and 3% to 5% nitric acid by mass fraction.

[0089] Optionally, a first etchant is used to chemically etch the metal plate to remove the porous alumina layer on the surface of the aluminum foil, thereby forming multiple spaced nanopits on the surface of the aluminum foil. After chemical etching, the metal plate is cleaned with deionized water and dried with nitrogen gas. A scanning electron microscope image of the metal plate with multiple nanopits after chemical etching to remove the porous structure is shown below. Figure 6 As shown, where, Figure 6 The left image is a lower-resolution scanning electron microscope (SEM) image, while the right image is a higher-resolution SEM image. Figure 6 It can be seen that the size and distribution of the multiple nano-pits are relatively uniform.

[0090] It should be noted that the first etching solution is an aqueous solution of phosphoric acid, chromic acid and nitric acid.

[0091] In this embodiment, the first etching solution includes phosphoric acid, chromic acid, and nitric acid. Phosphoric acid has a high density and can act as a carrier for corrosive substances in the first etching solution, thus corroding the metal plate; simultaneously, phosphoric acid can provide H₂. + The etching process passesivates the formed nano-pits, preventing them from being over-etched. Chromic acid enhances the corrosive effect of the first etching solution, while nitric acid dissolves the alumina film on the metal plate surface, thus removing the porous structure. In this embodiment, chemical etching removes the porous structure (porous oxide film layer) from the metal plate surface, leaving multiple nano-pits spaced apart (e.g., periodically arranged nano-pits) on the surface. After the first anodizing of the metal plate, the top (i.e., the part near the surface) of the porous structure formed on the metal plate surface is disordered, but the root or bottom (i.e., the bottom of the pore) is relatively ordered and uniform. That is, the size and arrangement period of the bottom of the porous structure are relatively uniform. Therefore, after removing the porous structure from the metal plate surface, the multiple nano-pits left on the metal plate surface are relatively uniform and ordered, which can serve as an induction for subsequent pore growth. This allows the next anodizing to re-grow pores based on these nano-pits and constrain them, resulting in more uniform and ordered pore sizes.

[0092] Specifically, the mass fraction of phosphoric acid in the first etching solution can be, but is not limited to, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc. If the mass fraction of phosphoric acid in the first etching solution is too low, the passivation effect of phosphoric acid is reduced, which can easily lead to excessive corrosion of the metal plate, causing changes in the structure and size of the nano-pits used to induce elongated holes, thus affecting the size of the multiple first recesses 210 of the obtained transfer mold 200. If the mass fraction of phosphoric acid in the first etching solution is too high, the viscosity of the first etching solution increases, reducing the fluidity of the first etching solution, which can easily lead to uneven corrosion of the metal plate, resulting in uneven structure and size of the multiple nano-pits, which also affects the size and structure of the multiple first recesses 210 of the obtained transfer mold 200.

[0093] Specifically, the mass fraction of chromic acid in the first etching solution can be, but is not limited to, 1.0%, 1.3%, 1.5%, 1.8%, 2.0%, 2.3%, 2.5%, 2.8%, 3%, etc. If the mass fraction of chromic acid in the first etching solution is too low, the corrosion of the porous oxide film layer with a porous structure on the surface of the metal plate will be too slow or incomplete. Slow corrosion reduces the production efficiency of the transfer mold 200, and incomplete corrosion of the porous structure affects the structure and size of the multiple nano-pits, thereby affecting the structure and size of the multiple first recesses 210 of the obtained transfer mold 200. If the mass fraction of chromic acid in the first etching solution is too high, the corrosion effect of the first etching solution will be too strong. After the metal plate is etched, the surface of the metal plate will be too flat, and the depth of the multiple nano-pits will be too small. This reduces the induction effect on subsequent hole formation and hole expansion, affecting the size of the multiple first recesses 210 on the obtained transfer mold 200.

[0094] Specifically, the mass fraction of nitric acid in the first etching solution can be, but is not limited to, 3.0%, 3.3%, 3.5%, 3.8%, 4.0%, 4.3%, 4.5%, 4.8%, 5%, etc. If the mass fraction of nitric acid in the first etching solution is too low, the corrosion rate of the porous structure will be too slow, reducing the production efficiency of the transfer mold 200. The disordered structure of the porous structure cannot be completely removed, and the transfer mold 200 with the preset size of the first recess 210 cannot be obtained. If the mass fraction of nitric acid in the first etching solution is too high, the porous structure of the metal plate will be corroded too quickly, resulting in excessive thinning of the metal plate, which is not conducive to the subsequent preparation of the imprinting mold. In addition, it is easy to corrode the metal plate too much, removing multiple nano-pits on the surface of the metal plate as well. The surface of the resulting metal plate is too flat, which reduces the induction effect of subsequent hole formation and hole expansion, affecting the size of the multiple first recesses 210 on the obtained transfer mold 200.

[0095] In some embodiments, the arrangement period n of the nano-pits is in the range of n≤200nm, the width w of the nano-pits is in the range of 10nm≤w≤50nm, and the depth h of the nano-pits is in the range of 10nm≤h≤50nm.

[0096] Specifically, the arrangement period n of the nano-pits is in the range of 50nm ≤ n ≤ 200nm. Specifically, the arrangement period n of the nano-pits can be, but is not limited to, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, 180nm, 190nm, 200nm, etc. If the arrangement period n of the nano-pits is too small, the arrangement period d1 of the plurality of first recesses 210 on the transfer mold 200 will be too small, increasing the difficulty of fabricating the transfer mold 200. If the arrangement period n of the nano-pits is too large, the arrangement period d1 of the plurality of first recesses 210 on the transfer mold 200 will be too large. When the transfer mold 200 is used to fabricate a cover plate, the arrangement period of the protrusions on the cover plate will be too large, easily forming Mie scattering, thereby reducing the transparency of the cover plate.

[0097] Specifically, the width w of the nano-pits can be, but is not limited to, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc. If the width w of the nano-pits is too small, it reduces the inducing effect of the nano-pits on subsequent pore formation and expansion, reduces the uniformity of the distribution of the multiple first recesses 210 of the obtained transfer mold 200, and reduces the width of the multiple first recesses 210, thereby reducing the anti-reflective and anti-transparency effect of the cover plate made using the transfer mold 200. If the width w of the nano-pits is too wide, the width of the multiple first recesses 210 of the obtained transfer mold 200 will be too wide, and the width of the protrusion of the cover plate made using the transfer mold 200 will be too wide, which will easily cause interference and reduce the anti-reflective and anti-transparency effect of the cover plate.

[0098] Specifically, the depth h of the nano-pits can be, but is not limited to, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc. If the depth h of the nano-pits is too shallow, the inducing effect of the nano-pits on subsequent pore formation and expansion will be reduced, the uniformity of the distribution of the multiple first recesses 210 of the obtained transfer mold 200 will be reduced, and the depth of the multiple first recesses 210 will be reduced, thereby reducing the anti-reflective and anti-transparency effect of the cover plate made using the transfer mold 200. If the depth h of the nano-pits is too deep, the depth of the multiple first recesses 210 of the obtained transfer mold 200 and the height of the protrusions of the cover plate made using the transfer mold 200 will be too high, which will easily cause interference and reduce the anti-reflective and anti-transparency effect of the cover plate.

[0099] In some embodiments, immersing the metal plate in a first etching solution for chemical etching to remove the porous structure, thereby creating multiple nano-pits on the surface of the metal plate, includes:

[0100] The metal plate is immersed in a first etching solution and chemically etched at a second temperature T2 of 50℃≤T2≤80℃ to remove the porous structure, resulting in multiple nano-pits on the surface of the metal plate.

[0101] Specifically, the second temperature T2 (i.e., the temperature of the first etching solution) can be, but is not limited to, 50℃, 55℃, 60℃, 65℃, 70℃, 75℃, 80℃, etc. If the temperature of the first etching solution is too low, the disordered porous structure on the surface of the metal plate will be difficult to remove completely, affecting the size and uniformity of the multiple first recesses 210 on the obtained transfer mold 200; if the temperature of the first etching solution is too high, the first etching solution will corrode the metal plate too strongly, and may also remove the multiple nano-pits on the surface of the metal plate used for induction, making the surface of the metal plate too flat, reducing the induction effect of the multiple nano-pits, and affecting the structure and size of the multiple first recesses 210 on the obtained transfer mold 200.

[0102] Optionally, the chemical etching time can be 2 to 4 hours. Specifically, the chemical etching time can be, but is not limited to, 2 hours, 2.5 hours, 3 hours, 3.5 hours, and 4 hours. If the chemical etching time is too short, the disordered porous structure on the surface of the metal plate will be difficult to remove completely, affecting the size and uniformity of the multiple first recesses 210 on the resulting transfer mold 200. If the chemical etching time is too long, it is easy to cause excessive corrosion of the metal plate, which will also remove the multiple nano-pits used for induction on the surface of the metal plate, making the surface of the metal plate too flat, reducing the induction effect of the multiple nano-pits, and affecting the structure and size of the multiple first recesses 210 on the resulting transfer mold 200.

[0103] In some embodiments, S104, the second anodizing of the metal plate includes:

[0104] The metal plate is subjected to a second anodic oxidation in a second electrolyte, wherein the second electrolyte comprises: 0.01 mol / L to 0.05 mol / L sulfuric acid, 0.2 mol / L to 0.5 mol / L phosphoric acid, and 0.1 g / L to 1 g / L aluminum sulfate.

[0105] Optionally, the metal plate is subjected to a second anodic oxidation in the second electrolyte, using the nano-pits on the metal plate as inducing holes, and pores are uniformly grown on the basis of the nano-pits on the metal plate to create holes in the metal plate.

[0106] In this embodiment, the second electrolyte includes sulfuric acid, phosphoric acid, and aluminum sulfate. Compared to the first electrolyte, the second electrolyte, phosphoric acid, replaces the oxalic acid in the first electrolyte. Phosphoric acid can form a film layer on the surface of the aluminum foil, which can smooth the surface, making the structure of the first recess 210 on the transfer mold 200 smoother. Sulfuric acid plays a conductive electrolytic role in the second electrolyte, dissolving the aluminum foil at the anode and forming an oxide film at the anode. Aluminum sulfate can provide aluminum ions (Al... 3+ This makes the second anodizing of the aluminum foil surface more uniform.

[0107] Specifically, the concentration of sulfuric acid in the second electrolyte can be, but is not limited to, 0.01 mol / L, 0.012 mol / L, 0.015 mol / L, 0.018 mol / L, 0.02 mol / L, 0.025 mol / L, 0.03 mol / L, 0.035 mol / L, 0.04 mol / L, 0.045 mol / L, 0.05 mol / L, etc. If the concentration of sulfuric acid in the second electrolyte is too low, the dissolution rate of the alumina film on the aluminum foil surface will be too slow, and the aperture of the first recess 210 on the transfer mold 200 will be too small, resulting in an insignificant anti-reflective effect on the cover plate made using the transfer mold 200. If the concentration of sulfuric acid in the second electrolyte is too high, the dissolution rate of the alumina film will be too fast, and the aperture of the first recess 210 on the transfer mold 200 will be too large, resulting in a cover plate made using the transfer mold 200 being prone to fogging or iridescent phenomena, affecting the appearance of the cover plate.

[0108] Specifically, the concentration of phosphoric acid in the second electrolyte can be, but is not limited to, 0.2 mol / L, 0.25 mol / L, 0.3 mol / L, 0.35 mol / L, 0.4 mol / L, 0.45 mol / L, 0.5 mol / L, etc. If the concentration of phosphoric acid in the second electrolyte is too low, the smoothing effect of phosphoric acid is reduced, resulting in excessive surface roughness of the transfer mold 200, which is prone to pitting. The cover plate made using this transfer mold 200 is also prone to pitting and other defects, affecting the appearance of the cover plate. If the concentration of phosphoric acid in the second electrolyte is too high, the hardness of the oxide film on the surface of the metal plate decreases, reducing the service life of the transfer mold 200. Furthermore, if the concentration of phosphoric acid in the second electrolyte is too high, the viscosity of the second electrolyte is too high, reducing the reaction rate of the second anodizing, limiting the growth of the pores, and making it difficult to obtain the predetermined structure and size of the first recess 210 on the transfer mold 200.

[0109] Specifically, the concentration of aluminum sulfate in the second electrolyte can be, but is not limited to, 0.1 g / L, 0.2 g / L, 0.3 g / L, 0.4 g / L, 0.5 g / L, 0.6 g / L, 0.7 g / L, 0.8 g / L, 0.9 g / L, 1.0 g / L, etc. If the concentration of aluminum sulfate in the second electrolyte is too low, the oxide film on the surface of the metal plate will be too thin, and the first recess 210 of the transfer mold 200 will not achieve the preset size and structure. If the concentration of aluminum sulfate in the second electrolyte is too high, it will affect the growth rate and uniformity of the oxide film on the surface of the metal plate. Uneven oxide film growth will affect the uniformity of the porous structure on the metal plate, thereby affecting the size uniformity of the multiple first recesses 210 of the obtained transfer mold 200.

[0110] In some embodiments, the second anodic oxidation of the metal plate in a second electrolyte includes:

[0111] The metal plate is immersed in a second electrolyte, wherein the third temperature T3 of the second electrolyte is in the range of 16℃ ≤ T3 ≤ 24℃; and

[0112] The second anodizing is performed at a second voltage U2 of 60V≤U2≤100V.

[0113] Specifically, the third temperature T3 of the second electrolyte can be, but is not limited to, 16℃, 17℃, 18℃, 19℃, 20℃, 21℃, 22℃, 23℃, 24℃, etc. If the third temperature T3 of the second electrolyte is too low, the aperture of the multiple first recesses 210 on the transfer mold 200 will be too small, resulting in an insignificant anti-reflective and anti-transparency effect on the cover plate made using the transfer mold 200. If the third temperature T3 of the second electrolyte is too high, the aperture of the multiple first recesses 210 on the transfer mold 200 will be too large, making the cover plate made using the transfer mold 200 prone to fogging or iridescent phenomena, affecting the appearance of the cover plate. In addition, it is easy to make the size of the multiple first recesses 210 on the transfer mold 200 uneven.

[0114] Specifically, the second voltage U2 (i.e., the voltage of the second anodizing) can be, but is not limited to, 60V, 70V, 80V, 90V, 100V, etc. If the second voltage U2 is too low, the aperture of the multiple first recesses 210 on the transfer mold 200 will be too small, making the anti-reflective and anti-transparency effect of the cover plate made using the transfer mold 200 not obvious; if the second voltage U2 is too high, the aperture of the multiple first recesses 210 on the transfer mold 200 will be too large, making the cover plate made using the transfer mold 200 prone to fogging or iridescent phenomena, affecting the appearance of the cover plate; in addition, it is easy to reduce the uniformity of the size of the multiple first recesses 210 on the transfer mold 200.

[0115] Optionally, the second anodizing time is 2 to 6 minutes. Specifically, the second anodizing time can be, but is not limited to, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, etc. If the second anodizing time is too short, the holes will not be formed sufficiently, and the size of the multiple first recesses 210 on the resulting transfer mold 200 will not meet the expected size; if the second anodizing time is too long, the uniformity of the multiple first recesses 210 on the resulting transfer mold 200 will be reduced.

[0116] In some embodiments, S105, enlarging the hole in the metal plate includes:

[0117] The metal plate is immersed in a second etching solution to enlarge the holes, wherein the second etching solution comprises: 0.4 mol / L to 0.8 mol / L phosphoric acid and 0.1 mol / L to 0.5 mol / L nitric acid.

[0118] In this embodiment, the second etching solution does not contain chromic acid, unlike the first etching solution, because chromic acid is too corrosive and can easily remove the pore structure formed during the pore-forming stage. The second etching solution can better avoid removing the pores formed by the second anodizing and can also effectively enlarge the pores formed by the second anodizing, resulting in a transfer mold 200 with a first recess 210 having a preset structure and size.

[0119] Specifically, the concentration of phosphoric acid in the second etching solution can be, but is not limited to, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, etc. If the concentration of phosphoric acid in the second etching solution is too low, the passivation effect of phosphoric acid is reduced, which can easily lead to excessive corrosion of the holes on the metal plate, affecting the size of the multiple first recesses 210 of the transfer mold 200. If the concentration of phosphoric acid in the second etching solution is too high, the viscosity of the second etching solution increases, reducing the fluidity of the second etching solution, which can easily lead to uneven corrosion of the metal plate, resulting in uneven size and structure of the multiple first recesses 210 of the transfer mold 200.

[0120] Specifically, the concentration of nitric acid in the second etching solution can be, but is not limited to, 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, etc. If the concentration of nitric acid in the second etching solution is too low, the hole-forming corrosion rate of the metal plate will be too slow, reducing the production efficiency of the transfer mold 200, and it may even be impossible to obtain a transfer mold 200 with the preset size of the first recess 210. If the concentration of nitric acid in the second etching solution is too high, the hole-forming of the metal plate will be corroded too quickly, and the size of the first recess 210 of the obtained transfer mold 200 will be too large, reducing the anti-reflection and anti-reflection effect of the cover plate made using the transfer mold 200.

[0121] In some embodiments, immersing the metal plate in a second etching solution to enlarge the holes includes:

[0122] The metal plate is immersed in the second etching solution, and the hole is enlarged at a fourth temperature T4 of 60℃≤T4≤80℃.

[0123] Specifically, the fourth temperature T4 (i.e., the temperature of the second etching solution) can be, but is not limited to, 60℃, 65℃, 70℃, 75℃, 80℃, etc. If the temperature of the second etching solution is too low, the hole enlargement of the metal plate will be insufficient, and the size of the multiple first recesses 210 of the transfer mold 200 will not reach the preset size, thus reducing the anti-reflection and anti-reflection effect of the cover plate made using the transfer mold 200. If the temperature of the second etching solution is too high, the second etching solution will corrode the metal plate too strongly, easily removing too many holes on the surface of the metal plate, so that the structure and size of the first recesses 210 of the transfer mold 200 cannot reach the preset size, thus reducing the anti-reflection and anti-reflection effect of the cover plate made using the transfer mold 200.

[0124] Optionally, the hole-expanding time can be 2 to 10 minutes. Specifically, the hole-expanding time can be, but is not limited to, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, and 10 minutes. If the hole-expanding time is too long, the second etching solution will corrode the metal plate too strongly, easily removing too many holes on the surface of the metal plate. This will prevent the structure and size of the first recessed portion 210 of the transfer mold 200 from reaching the preset size, reducing the anti-reflection and anti-transparency effect of the cover plate made using the transfer mold 200. If the hole-expanding time is too short, the hole-expanding of the metal plate will be insufficient, and the size of the multiple first recessed portions 210 of the transfer mold 200 will not reach the preset size, reducing the anti-reflection and anti-transparency effect of the cover plate made using the transfer mold 200.

[0125] In some embodiments, the metal plate is subjected to a second anodizing and hole enlargement processes alternately multiple times.

[0126] Optionally, the second anodizing and hole-expanding are alternated 3 to 10 times. In other words, the hole-forming and hole-expanding are alternated 3 to 10 times. Specifically, it can be, but is not limited to, 3, 4, 5, 6, 7, 8, 9, 10 times, etc. If the number of alternations between the second anodizing and hole-expanding is too small, the sidewall of the first recess 210 on the transfer mold 200 cannot have a gradient structure, reducing the anti-reflective and anti-transparency effect of the cover plate made using the transfer mold 200. If the number of alternations between the second anodizing and hole-expanding is too large, the preparation efficiency of the transfer mold 200 is reduced, and the preparation cost of the transfer mold 200 is increased.

[0127] In this embodiment, by alternating between the second anodizing and the hole enlargement multiple times, the sidewall of the first recess 210 of the transfer mold 200 can have a parabolic gradient structure, and the cover plate made by the transfer mold 200 has a better anti-reflective and anti-transparency effect.

[0128] Please see again Figure 1 and Figure 2 In some embodiments, the width a1 of the first recess 210 is in the range of 40nm≤a1≤200nm; the depth h1 of the first recess 210 is in the range of 100nm≤h1≤500nm.

[0129] Specifically, the width a1 of the first recessed portion 210 can be, but is not limited to, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm, 200nm, etc. If the width a1 of the first recessed portion 210 is too small, it reduces the anti-reflective and anti-transparency effect of the cover plate made using the transfer mold 200; if the width a1 of the first recessed portion 210 is too large, the width of the protrusion of the cover plate made using the transfer mold 200 will be too wide, which is prone to interference and reduces the anti-reflective and anti-transparency effect of the cover plate.

[0130] Furthermore, the width a1 of the first recess 210 is in the range of 100nm ≤ a1 ≤ 200nm. This allows the cover plate made using the transfer mold 200 to have better anti-reflective and anti-transparency effects.

[0131] Specifically, the depth h1 of the first recess 210 can be, but is not limited to, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, etc. If the depth h1 of the first recess 210 is too shallow, the anti-reflective and anti-transparency effect of the cover plate made using the transfer mold 200 will be reduced; if the depth h1 of the first recess 210 is too deep, the height of the protrusion of the cover plate made using the transfer mold 200 will be too high, which will easily cause interference and reduce the anti-reflective and anti-transparency effect of the cover plate.

[0132] Furthermore, the depth h1 of the first recess 210 is in the range of 200nm ≤ h1 ≤ 300nm. Specifically, the depth h1 of the first recess 210 can be, but is not limited to, 200nm, 220nm, 240nm, 260nm, 280nm, 300nm, etc. This allows the cover plate made using the transfer mold 200 to have better anti-reflective and anti-transparency effects.

[0133] Please see again Figure 1 and Figure 2This application also provides a transfer mold 200, which is prepared using the preparation method of the transfer mold 200 of this application.

[0134] Optionally, the transfer mold 200 includes a plurality of first recesses 210 spaced apart on its surface. The arrangement period d1 of the plurality of first recesses 210 is in the range of d1≤200nm, the width of the first recesses 210 is in the range of 40nm≤a1≤200nm, and the depth h1 of the first recesses 210 is in the range of 100nm≤h1≤500nm.

[0135] Optionally, when the metal plate is aluminum foil, the surface of the transfer mold 200 has a layer of porous alumina film (AAO). The holes in the porous alumina film of the transfer mold 200 are the first recessed portion 210.

[0136] For a detailed description of other aspects of the transfer mold 200 and the first recess 210, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here.

[0137] The transfer mold 200 of this application is prepared using the above-described method. The transfer mold 200 is obtained by sequentially performing a first anodizing, chemical etching, a second anodizing, and hole enlargement processes on a metal plate. This preparation method is applicable not only to the preparation of small-sized transfer molds 200, but also to the preparation of large-sized (e.g., larger than 8 inches) transfer molds 200. Furthermore, the preparation method of the transfer mold 200 of this application has low preparation cost, thereby reducing the preparation cost of the cover plate prepared using the transfer mold 200. Furthermore, the size of the first recess 210 of the transfer mold 200 prepared by the method of this application is easy to adjust and control. By making the arrangement period of the first recess 210 less than or equal to 200 nm, the arrangement period of the protrusion of the cover plate prepared by the transfer mold 200 can be less than or equal to 200 nm, thereby greatly reducing the reflectivity of the cover plate and increasing the transmittance of the cover plate. When the cover plate is applied to the terminal to protect the display screen of the terminal, the terminal can have a better display effect.

[0138] Figure 7 This is a schematic diagram of the structure of an embossing mold 300 according to an embodiment of this application.

[0139] Please see Figure 7This application embodiment also provides an embossing mold 300, which is obtained by two transfers using the transfer mold 200 of this application embodiment. The embossing mold 300 includes a plurality of second recesses 310 spaced apart on its surface. The plurality of first recesses 210 have the same structure as the plurality of second recesses 310. The arrangement period d2 of the plurality of second recesses 310 is in the range of d2≤200nm. The width a2 of the second recesses 310 is in the range of 40nm≤a2≤200nm. The depth h2 of the second recesses 310 is in the range of 100nm≤h2≤500nm.

[0140] Optionally, the embossing mold 300 may be made of, but is not limited to, materials with a certain degree of hardness and toughness, such as polydimethylsiloxane (PDMS).

[0141] Specifically, by using the transfer mold 200 for two pressing and copying processes, an impression mold 300 (also called a sub-mold) with the same structure as the transfer mold 200 is obtained. For example, a layer of polydimethylsiloxane adhesive is coated on the surface of the transfer mold having the first recess 210, the polydimethylsiloxane adhesive is cured, and demolding is performed to obtain an intermediate sub-mold with multiple protrusions; polydimethylsiloxane adhesive is coated on the surface of the intermediate sub-mold having multiple protrusions, the polydimethylsiloxane adhesive is cured, and demolding is performed to obtain an impression mold 300 with multiple second recesses 310.

[0142] In this embodiment, the transfer mold 200 is used to form the imprinting mold 300 through two transfers or imprints. The imprinting mold 300 is then used to prepare the cover plate. Since the transfer mold 200 is made of metal and is relatively hard, directly using the transfer mold 200 to form a textured structure on the photoresist layer can easily result in incomplete transfer or defects in the structure of the multiple first recesses 210 on the transfer mold 200. Because the imprinting mold 300 is made of a relatively soft material with a certain degree of hardness, after the transfer mold 200 is formed into the imprinting mold 300 through two transfers, the imprinting mold 300 is then used to form a textured structure on the photoresist layer. This allows for a better transfer of the structure from the transfer mold 200 to the photoresist layer, resulting in a more precise structure of the protrusions on the surface of the cover plate and a better anti-reflective and anti-transparency effect.

[0143] Furthermore, the embossing mold 300 of this application is obtained by two transfers using a transfer mold 200. The transfer mold 200 is made by sequentially performing a first anodizing, chemical etching, a second anodizing, and hole enlargement processes on a metal plate. This method of preparing the transfer mold 200 is applicable not only to the preparation of small-sized transfer molds 200, but also to the preparation of large-sized (e.g., larger than 8 inches) transfer molds 200. In addition, the preparation method of the transfer mold 200 of this application has low preparation cost, thereby reducing the preparation cost of the embossing mold 300 and the cover plate prepared using the transfer mold 200. Furthermore, the size of the first recess 210 of the transfer mold 200 prepared by the method of this application is easy to adjust and control. By making the arrangement period of the first recess 210 less than or equal to 200 nm, the arrangement period of the protrusion of the cover plate prepared by the transfer mold 200 can be less than or equal to 200 nm, thereby greatly reducing the reflectivity of the cover plate and increasing the transmittance of the cover plate. When the cover plate is applied to the terminal to protect the display screen of the terminal, the terminal can have a better display effect.

[0144] Optionally, the arrangement period d2 of the plurality of second recesses 310 is in the range of 50nm ≤ d2 ≤ 200nm. Specifically, the arrangement period d2 of the plurality of second recesses 310 can be, but is not limited to, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, 180nm, 190nm, 200nm, etc. If the arrangement period d2 of the plurality of second recesses 310 is too small, it increases the difficulty of manufacturing the transfer mold 200; if the arrangement period d2 of the plurality of second recesses 310 is too large, when the imprinting mold 300 is used to manufacture the cover plate, the arrangement period of the protrusions on the cover plate is too large, which easily forms Mie scattering, thereby reducing the transparency of the cover plate.

[0145] Specifically, the width a2 of the second recessed portion 310 can be, but is not limited to, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm, 200nm, etc. If the width a2 of the second recessed portion 310 is too small, it reduces the anti-reflective and anti-transparency effect of the cover plate made using the embossing mold 300; if the width a2 of the second recessed portion 310 is too large, the width of the protrusion of the cover plate made using the embossing mold 300 will be too wide, which is prone to interference and reduces the anti-reflective and anti-transparency effect of the cover plate.

[0146] Furthermore, the width a2 of the second recess 310 is in the range of 100nm ≤ a2 ≤ 200nm. This allows the cover plate made using the embossing mold 300 to have better anti-reflective and anti-transparency effects.

[0147] Specifically, the depth h2 of the second recess 310 can be, but is not limited to, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, etc. If the depth h2 of the second recess 310 is too shallow, the anti-reflective and anti-transparency effect of the cover plate made using the embossing mold 300 will be reduced; if the depth h2 of the second recess 310 is too deep, the height of the protrusion of the cover plate made using the embossing mold 300 will be too high, which will easily cause interference and reduce the anti-reflective and anti-transparency effect of the cover plate.

[0148] Furthermore, the depth h2 of the second recessed portion 310 is in the range of 200nm ≤ h2 ≤ 300nm. Specifically, the depth h2 of the second recessed portion 310 can be, but is not limited to, 200nm, 220nm, 240nm, 260nm, 280nm, 300nm, etc. This allows the cover plate made using the embossing mold 300 to have better anti-reflective and anti-transparency effects.

[0149] Figure 8 This is a schematic flowchart of a method for preparing a cover plate 500 according to an embodiment of this application. Figure 9 This is a schematic diagram of the structure of a cover plate 500 according to an embodiment of this application. Figure 10 The cover plate 500 of one embodiment of this application is along Figure 9 A schematic diagram of the cross-sectional structure along the AA direction.

[0150] Please see Figures 8 to 10 This application also provides a method for preparing a cover plate 500, the method comprising:

[0151] S401 provides a substrate;

[0152] Optionally, the substrate may be, but is not limited to, a glass substrate, a resin substrate (e.g., polyethylene terephthalate, or PET for short), etc.

[0153] S402, a photoresist layer is formed on the surface of the substrate;

[0154] Optionally, a photoresist solution is applied to a substrate, and the solvent in the photoresist solution is removed to form a photoresist layer.

[0155] S403, a textured structure is imprinted on the surface of the photoresist layer using the imprinting mold 300 described in this application, wherein the textured structure is complementary to the structure of the plurality of second recesses 310 of the imprinting mold 300; and

[0156] Optionally, an imprinting mold 300 is stacked on a photoresist layer, with the second recess 310 facing the photoresist layer. A certain pressure is applied to transfer the structure of the second recess 310 on the imprinting mold 300 to the photoresist layer. The photoresist layer is then cured to obtain a photoresist layer with a textured structure. The imprinting mold 300 is then removed to obtain a stacked substrate / photoresist layer, wherein the second recess 310 faces away from the substrate.

[0157] S404, dry etching is performed to obtain a cover plate 500, wherein the cover plate 500 includes a plurality of protrusions 510 spaced apart on its surface, the arrangement period d3 of the plurality of protrusions 510 is in the range of d3≤200nm, and the plurality of protrusions 510 are structurally complementary to the plurality of second recesses 310 of the imprinting mold 300.

[0158] Optionally, the dry etching can be, but is not limited to, plasma etching.

[0159] Optionally, the stacked substrate / photoresist layers are placed within the dry etching chamber of the plasma etching machine. An inductively coupled plasma (ICP) power supply with a power of 700W to 2000W and a frequency of 13.56MHz is used to control the plasma density and composition. The lower electrode of the plasma etching machine uses a 2MHz capacitively coupled plasma (CCP) power supply with a power of 300W to 1500W to control the ion energy and direction. Dry etching is performed using an etching gas (e.g., a mixture of BCl3, C4F6, and O2 in a volume ratio of 10:3:1), with the temperature controlled between 60°C and 130°C, the He pressure between 2T and 7T, and the pressure of the dry etching chamber between 1.0mT and 4.0mT, to etch the photoresist layer and the substrate, thereby forming a cover plate 500 after the substrate is etched. The cover plate 500 has a plurality of protrusions 510 that are complementary to the plurality of second recesses 310 of the imprinting mold 300.

[0160] Optionally, during plasma etching, the photoresist layer is etched proportionally to the substrate, so that the structure of the protrusion 510 formed on the cover plate 500 is the same as the texture structure.

[0161] Understandably, the etching rates of the photoresist layer and the substrate are equal or nearly equal. That is, during plasma etching, the ratio of photoresist layer to substrate is 1.

[0162] For a detailed description of the same features as described above, such as the embossing mold 300 and the second recess 310, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0163] The method for fabricating the cover plate 500 in this embodiment first forms a photoresist layer on a substrate, then uses an imprinting mold 300 to imprint a textured structure on the surface of the photoresist layer. Next, plasma etching is performed on the photoresist layer and the substrate, resulting in a complementary structure between the protrusion 510 on the cover plate 500 and the second recess 310 on the imprinting mold 300. The cover plate 500 fabricated using this method can more accurately and completely replicate the structure on the imprinting mold 300, allowing for more precise design of the protrusion 510. This results in higher light transmittance and lower reflectivity for the cover plate 500, achieving better anti-reflection and anti-transmittance effects. Furthermore, this method is easy to implement and has low fabrication costs, further reducing the fabrication cost of the cover plate 500.

[0164] Please see Figure 9 and Figure 10 This application embodiment also provides a cover plate 500, the cover plate 500 including: a plurality of protrusions 510 spaced apart on its surface, the arrangement period d3 of the plurality of protrusions 510 being in the range of: d3≤200nm.

[0165] The cover plate 500 of this application embodiment can be applied to terminals such as mobile phones, tablets, laptops, desktop computers, smart bracelets, smartwatches, e-readers, and game consoles. The cover plate 500 of this application embodiment can serve as a protective cover 500 for the terminal's display screen, or as a protective cover for the terminal's camera module. In the following embodiments of this application, the cover plate 500 is described as an example of being used as a protective cover 500 for the terminal's display screen, and should not be construed as limiting the cover plate 500 of this application embodiment.

[0166] It should be noted that when the cover plate 500 is applied to the display screen of the terminal, the plurality of micro-nano structures are positioned away from the display screen.

[0167] Optionally, the arrangement period d3 of the plurality of protrusions 510 is in the range of 50nm ≤ d3 ≤ 200nm. Specifically, the arrangement period d3 of the plurality of protrusions 510 can be, but is not limited to, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, 180nm, 190nm, 200nm, etc. If the arrangement period d3 of the plurality of protrusions 510 on the cover plate 500 is too small, it increases the difficulty of manufacturing the cover plate 500; if the arrangement period d3 of the plurality of protrusions 510 on the cover plate 500 is too large, it makes the cover plate 500 prone to Mie scattering, thereby reducing the transparency of the cover plate 500.

[0168] Optionally, the cover plate 500 further includes a cover body portion 520, and the plurality of protrusions 510 are spaced apart from the surface of the cover body portion 520. The cover body portion 520 and the plurality of protrusions 510 are an integral structure.

[0169] Optionally, the cover plate 500 may be made of glass or resin. The resin may be, but is not limited to, polyethylene terephthalate (PET).

[0170] The anti-reflection principle of the cover plate 500 in this application is based on the diffraction and interference phenomena of light. Coherent light waves at discontinuous media will interfere with each other and superimpose, thereby causing the reflected light and transmitted light to be redistributed, which reduces the intensity of the reflected light and achieves the anti-reflection effect.

[0171] The cover plate 500 of this application embodiment includes a plurality of protrusions 510 spaced apart on its surface, wherein the arrangement period d3 of the plurality of protrusions 510 is in the range of d3≤200nm. By designing the dimensions of the protrusions 510 on the surface of the cover plate 500, the cover plate 500 can have a low reflectivity and a high light transmittance, thus enabling the display screen to have a better display effect when used as a protective cover plate 500 for the display screen. In addition, the protrusions 510 are directly formed on the cover plate 500, that is, the cover body 520 and the protrusions 510 are an integral structure, which makes the protrusions 510 less likely to fall off after long-term use, thereby giving the cover plate 500 a longer service life.

[0172] In some embodiments, the width a3 of the protrusion 510 is in the range of 40nm≤a3≤200nm.

[0173] Specifically, the width a3 of the protrusion 510 can be, but is not limited to, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm, 200nm, etc. If the width a3 of the protrusion 510 is too small, it reduces the anti-reflection and anti-reflection effect of the cover plate 500; if the width a3 of the protrusion 510 is too large, interference is likely to occur, reducing the anti-reflection and anti-reflection effect of the cover plate 500.

[0174] Furthermore, the width a3 of the protrusion 510 is in the range of 100nm ≤ a3 ≤ 200nm. This allows the cover plate 500 to have a better anti-reflective and anti-transparency effect.

[0175] In some embodiments, the height h3 of the protrusion 510 is in the range of 100nm≤h3≤500nm.

[0176] Specifically, the height h3 of the protrusion 510 can be, but is not limited to, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, etc. If the height h3 of the protrusion 510 is too small, the anti-reflection and anti-transparency effect of the cover plate 500 will be reduced; if the height h3 of the protrusion 510 is too deep and large, interference is likely to occur, reducing the anti-reflection and anti-transparency effect of the cover plate 500.

[0177] Furthermore, the height h3 of the protrusion 510 is in the range of 200nm ≤ h3 ≤ 300nm. Specifically, the height h3 of the protrusion 510 can be, but is not limited to, 200nm, 220nm, 240nm, 260nm, 280nm, 300nm, etc. This allows the cover plate 500 to have a better anti-reflective and anti-transparency effect.

[0178] Optionally, the ratio of the height to the width of the protrusion 510 ranges from 1 to 2. Specifically, the ratio of the height to the width of the protrusion 510 can be, but is not limited to, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, etc. A ratio that is too large or too small will reduce the anti-reflective and anti-transparency effect of the cover plate 500. When the ratio of the height to the width of the protrusion 510 is between 1 and 2, the cover plate 500 has a better anti-reflective and anti-transparency effect.

[0179] Furthermore, the ratio of the height to the width of the protrusion 510 ranges from 1.3 to 1.7. This gives the cover plate 500 a better anti-reflective and anti-transparency effect.

[0180] The cover plate 500 and its preparation method of this application will be further described below through specific embodiments.

[0181] Examples 1 to 24

[0182] The preparation methods of the cover plate 500 in Examples 1 to 24 include:

[0183] (1) Preparation of transfer mold 200, including:

[0184] (i) Provide aluminum foil with a purity of 99.999%, which can be easily electrochemically polished (voltage of 20V) with ethanol perchloric acid at a volume ratio of 4:1 (temperature of 0°C) to a surface roughness of less than or equal to 5nm.

[0185] (ii) The metal plate is subjected to a first anodic oxidation in a first electrolyte to form a porous structure on the surface of the metal plate. The first electrolyte comprises 0.03 mol / L sulfuric acid, 0.3 mol / L oxalic acid and 0.5 g / L aluminum sulfate. The temperature of the first electrolyte is 0°C, the first voltage U1 of the first anodic oxidation is 80 V, and the time of the first anodic oxidation is 70 min.

[0186] (iii) The metal plate is chemically etched to remove the porous structure, thereby forming a plurality of spaced nano-pits on the surface of the metal plate; wherein the first etching solution comprises 7% phosphoric acid, 2% chromic acid and 4% nitric acid by mass fraction, and the second temperature T2 of the first etching solution is 65°C.

[0187] (iv) The metal plate is subjected to a second anodic oxidation in a second electrolyte to create pores, wherein the temperature of the second electrolyte T3 is 20°C and the second voltage U2 for the second anodic oxidation is 80V; and

[0188] (v) The metal plate is immersed in a second etching solution to enlarge the hole, wherein the temperature of the second etching solution T4 is 70°C; the second anodizing and hole enlargement are repeated multiple times to obtain the transfer mold 200.

[0189] For parameters such as the second electrolyte and the second etching solution in each embodiment, please refer to Table 1 below.

[0190] (2) Preparation of embossing mold 300: Using transfer mold 200, polydimethylsiloxane is transferred from both sides to obtain embossing mold 300. Embossing mold 300 has a plurality of second recesses 310 spaced apart.

[0191] (3) Provide a glass substrate and form a photoresist layer on the glass substrate;

[0192] (4) A textured structure is imprinted on the surface of the photoresist layer using an imprinting mold 300, the textured structure being complementary to the structure of the second recess 310; and

[0193] (5) A mixture of BCl3, C4F6 and O2 in a volume ratio of 10:3:1 is used as an etching gas to perform plasma to obtain a cover plate 500, wherein the cover plate 500 has a plurality of protrusions 510 spaced apart.

[0194] Comparative Example 1

[0195] A glass substrate was used as the cover plate 500 for this comparative example.

[0196] Comparative Example 2

[0197] The difference between this comparative example and Example 5 is that only one second anodizing and pore-expanding process is performed, with the second anodizing time being 20 minutes and the pore-expanding time being 16 minutes.

[0198] The visible light transmittance of the cover plates of Examples 1 to 24 was tested at 500°C. The number of test cycles is shown in Table 2 below.

[0199] Table 1. Parameter information of the preparation process of cover plate 500 in Examples 1 to 24.

[0200]

[0201]

[0202] Table 2 Performance parameters of cover plate 500 in Examples 1 to 24

[0203] Example Number of loops (times) The period d3 of the protrusion The width a3 of the protrusion The height h3 of the protrusion Light transmittance Example 1 4 100nm 100nm 80nm 94.10％ Example 2 4 130nm 120nm 80nm 94.50％ Example 3 4 180nm 160nm 80nm 94.30％ Example 4 4 110nm 110nm 230nm 95.60％ Example 5 4 140nm 125nm 235nm 95.00％ Example 6 4 190nm 182nm 232nm 95.90％ Example 7 3 70nm 70nm 60nm 93.70％ Example 8 5 120nm 110nm 98nm 94.60％ Example 9 4 60nm 50nm 225nm 93.10％ Example 10 4 100nm 80nm 232nm 93.50％ Example 11 4 160nm 140nm 238nm 95.10％ Example 12 4 200nm 180nm 242nm 95.50％ Example 13 4 100nm 80nm 227nm 95.80％ Example 14 4 120nm 960nm 230nm 95.60％ Example 15 4 160nm 1380nm 238nm 95.30％ Example 16 4 180nm 1450nm 240nm 95.00％ Example 17 4 125nm 102nm 230nm 94.70％ Example 18 4 132nm 113nm 231nm 94.70％ Example 19 4 148nm 136nm 236nm 95.70％ Example 20 4 162nm 143nm 238nm 95.70％ Example 21 4 70nm 50nm 230nm 95.70％ Example 22 4 100nm 85nm 232nm 95.50％ Example 23 4 180nm 140nm 236nm 95.56％ Example 24 4 200nm 150nm 238nm 95.70％ Comparative Example 1 / / / / 92％ Comparative Example 2 1 200nm 120nm 230nm 92.50％

[0204] As can be seen from the test results of Examples 1 to 24 and Comparative Example 1 in Tables 1 and 2, compared with the 92% light transmittance of the glass substrate, the light transmittance of the cover plate 500 made by the method of this application using the glass plate is greatly improved, and the light transmittance of the cover plate 500 is greater than or equal to 93.1%, that is, the light transmittance is improved by at least 1.1%.

[0205] As can be seen from the test results of Examples 1 to 3 in Tables 1 and 2, under the condition that other conditions remain unchanged, as the hole expansion time increases each time, the period and width of the protrusion 510 of the cover plate 500 also increase, and the light transmittance of the cover plate 500 first gradually increases and then gradually decreases.

[0206] As can be seen from the test results of Examples 1 and 4, Examples 2 and 5, Examples 3 and 6 in Tables 1 and 2, under the condition that other conditions remain unchanged, increasing the time of each second anodizing will increase the period, width and height of the protrusion 510 of the cover plate 500, and the light transmittance of the cover plate 500 will also increase.

[0207] As can be seen from the test results of Examples 1, 7 and 8, when the conditions of the first anodizing, chemical timing, second anodizing and hole expansion, the first electrolyte, the first etching solution, the second electrolyte, the second etching solution, etc. are all controlled within a certain range, and when the number of cycles is within a certain range, as the number of cycles increases, the period, width and height of the protrusion 510 of the cover plate 500 gradually increase, and the light transmittance of the cover plate 500 also gradually increases.

[0208] As can be seen from the test results of Example 5 and Comparative Example 2, compared with the comparative example 2 which uses a longer second anodizing hole formation time and a longer hole expansion time, the cover plate 500 prepared in Example 5 has a higher light transmittance.

[0209] The test results from Examples 5, 9 to 12 show that, when other conditions remain unchanged, as the concentration of sulfuric acid in the second electrolyte increases, the period of the protrusion 510 of the prepared cover plate 500 gradually increases, as do the width and height of the protrusion 510. However, the change in the sulfuric acid concentration in the second electrolyte has a greater impact on the period and width of the protrusion 510 than on its height. The prepared cover plates 500 all exhibit high light transmittance.

[0210] The test results from Examples 5 and 13 to 16 show that, when other conditions remain unchanged, as the concentration of phosphoric acid in the second electrolyte increases, the period of the protrusion 510 of the cover plate 500 gradually increases, as do the width and height of the protrusion 510. However, the change in phosphoric acid concentration in the second electrolyte has a greater impact on the period and width of the protrusion 510 than on its height. The resulting cover plates 500 all exhibit high light transmittance. Furthermore, the test results from Examples 9 to 12 and 13 to 16 show that the change in sulfuric acid concentration in the second electrolyte has a greater impact on the size of the protrusion 510 than the change in phosphoric acid concentration.

[0211] The test results from Examples 5, 17 to 20 show that, when other conditions remain unchanged, as the concentration of phosphoric acid in the second etching solution increases, the period of the protrusion 510 of the cover plate 500 gradually increases, as do the width and height of the protrusion 510. However, the change in the phosphoric acid concentration in the second etching solution has a greater impact on the period and width of the protrusion 510 than on its height. The resulting cover plates 500 all exhibit high light transmittance.

[0212] The test results from Examples 5 and 21 to 24 show that, when other conditions remain unchanged, as the concentration of nitric acid in the second etching solution increases, the period of the protrusion 510 of the cover plate 500 gradually increases, as do the width and height of the protrusion 510. However, the change in the phosphoric acid concentration in the second etching solution has a greater impact on the period and width of the protrusion 510 than on its height. The resulting cover plates 500 all exhibit high light transmittance. Furthermore, the test results from Examples 17 to 20 and 21 to 24 show that the change in the concentration of nitric acid in the second etching solution has a greater impact on the size of the protrusion 510 than the change in the concentration of phosphoric acid.

[0213] Figure 11 This is a schematic diagram of the structure of a terminal 600 according to an embodiment of this application. Figure 12 This is a partial exploded structural diagram of a terminal 600 according to an embodiment of this application. Figure 13 This is a circuit block diagram of a terminal 600 according to an embodiment of this application.

[0214] Please see Figures 11 to 13 This application also provides a terminal 600, which includes a display screen 610, a cover plate 500 as described in this application embodiment, and a processor 630. The display screen 610 has a display surface 611; the cover plate 500 is stacked on the display surface 611 of the display screen 610 to protect the display screen 610; the processor 630 is electrically connected to the display screen 610 and is used to control the display screen 610 to display.

[0215] The terminal 600 in this application embodiment can be, but is not limited to, a mobile phone, tablet computer, laptop computer, desktop computer, smart bracelet, smartwatch, e-reader, game console, or other portable terminal 600.

[0216] For a detailed description of the cover plate 500, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here.

[0217] Optionally, the display screen 610 may be, but is not limited to, one or more of the following: liquid crystal display screen, light-emitting diode display screen (LED display screen), micro light-emitting diode display screen (Micro LED display screen), mini LED display screen, organic light-emitting diode display screen (OLED display screen).

[0218] Optionally, processor 630 includes one or more general-purpose processors, wherein the general-purpose processor can be any type of device capable of processing electronic instructions, including a central processing unit (CPU), microprocessor, microcontroller, main processor, controller, and ASIC, etc. Processor 630 is used to execute various types of digital storage instructions, such as software or firmware programs stored in memory, which enables the computing device to provide a wide range of services.

[0219] Optionally, the terminal 600 of this application further includes a memory 650. The memory 650 is electrically connected to the processor 630 and is used to store the program code required for the processor 630 to run, the program code required to control the display screen 610, the display content of the display screen 610, etc.

[0220] Optionally, memory 650 may include volatile memory, such as random access memory (RAM); memory 650 may also include non-volatile memory (NVM), such as read-only memory (ROM), flash memory (FM), hard disk drive (HDD), or solid-state drive (SSD). Memory 650 may also include combinations of the above types of memory.

[0221] In some embodiments, the terminal 600 of this application further includes a mid-frame 620, a camera module 670, and a housing 640. The mid-frame 620 is disposed between the display screen 610 and the housing 640, and the side of the mid-frame 620 is exposed between the housing 640 and the display screen 610. The mid-frame 620 and the housing 640 enclose an accommodating space (not shown), which is used to accommodate the processor 630, the memory 650, and the camera module 670. The camera module 670 is electrically connected to the processor 630 and is used to take pictures under the control of the processor 630. Understandably, the display surface 611 is disposed away from the mid-frame 620 and the housing 640.

[0222] Optionally, the housing 640 includes a light-transmitting portion 641, through which the camera module 670 can capture images; that is, in this embodiment, the camera module 670 is a rear-facing camera module. It is understood that in other embodiments, the light-transmitting portion 641 may be disposed on the display screen 610; that is, the camera module 670 is a front-facing camera module. In the schematic diagram of this embodiment, the light-transmitting portion 641 is shown as an opening. In other embodiments, the light-transmitting portion 641 may not be an opening, but may be made of a light-transmitting material, such as plastic or glass. In some embodiments, the light-transmitting portion 641 is the cover plate 500 of this application embodiment.

[0223] It is understood that the terminal 600 described in this embodiment is merely one form of the terminal 600 used by the cover plate 500, and should not be construed as a limitation on the terminal 600 provided in this application, nor should it be construed as a limitation on the cover plate 500 provided in various embodiments of this application.

[0224] In this application, the terms "embodiment" and "implementation" mean that a specific feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of this application. The appearance of these phrases in various locations throughout the specification does not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this application can be combined with other embodiments. Furthermore, it should be understood that the features, structures, or characteristics described in the various embodiments of this application can be arbitrarily combined to form yet another embodiment that does not depart from the spirit and scope of the technical solution of this application, provided there is no contradiction between them.

[0225] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application should not depart from the spirit and scope of the technical solutions of this application.

Claims

1. A method for preparing a transfer mold, characterized in that, The preparation method includes: Metal sheets are provided; The metal plate is subjected to a first anodizing process to form a porous structure on the surface of the metal plate. The metal plate is chemically etched to remove the porous structure, thereby forming multiple nano-pits spaced apart on the surface of the metal plate. The metal plate is subjected to a second anodizing to create pores; and The metal plate is enlarged to obtain a transfer mold, wherein the transfer mold includes a plurality of first recesses spaced apart on its surface, and the arrangement period d1 of the plurality of first recesses is in the range of d1≤200nm.

2. The method for preparing a transfer mold according to claim 1, characterized in that, The provided metal plate includes: The metal plate is electrochemically polished to reduce the surface roughness of the metal plate to less than or equal to 5 nm.

3. The method for preparing a transfer mold according to claim 1, characterized in that, The first anodizing of the metal plate to form a porous structure on the surface of the metal plate includes: The metal plate is subjected to a first anodic oxidation in a first electrolyte to form a porous structure on the surface of the metal plate. The first electrolyte comprises: 0.015 mol / L to 0.05 mol / L sulfuric acid, 0.1 mol / L to 0.5 mol / L oxalic acid, and 0.1 g / L to 1 g / L aluminum sulfate.

4. The method for preparing a transfer mold according to claim 3, characterized in that, The step of performing a first anodic oxidation on the metal plate in a first electrolyte to form a porous structure on the surface of the metal plate includes: The metal plate is immersed in a first electrolyte, wherein the first temperature T1 of the first electrolyte is in the range of -3℃ ≤ T1 ≤ 3℃; and Under a first voltage U1 of 60V≤U1≤120V, a first anodizing is performed to form a porous structure on the surface of the metal plate.

5. The method for preparing a transfer mold according to claim 1, characterized in that, The metal plate is chemically etched to remove the porous structure, resulting in multiple nano-pits on the surface of the metal plate, including: The metal plate is immersed in a first etching solution for chemical etching to remove the porous structure, resulting in multiple nano-pits on the surface of the metal plate. The first etching solution comprises 4% to 10% phosphoric acid, 1% to 3% chromic acid and 3% to 5% nitric acid by mass fraction.

6. The method for preparing a transfer mold according to claim 5, characterized in that, The arrangement period n of the nano-pits is in the range of n≤200nm, the width w of the nano-pits is in the range of 10nm≤w≤50nm, and the depth h of the nano-pits is in the range of 10nm≤h≤50nm.

7. The method for preparing a transfer mold according to claim 5, characterized in that, The step of immersing the metal plate in a first etching solution for chemical etching to remove the porous structure and create multiple nano-pits on the surface of the metal plate includes: The metal plate is immersed in a first etching solution and chemically etched at a second temperature T2 of 50℃≤T2≤80℃ to remove the porous structure, resulting in multiple nano-pits on the surface of the metal plate.

8. The method for preparing a transfer mold according to claim 1, characterized in that, The second anodizing of the metal plate includes: The metal plate is subjected to a second anodic oxidation in a second electrolyte, wherein the second electrolyte comprises: 0.01 mol / L to 0.05 mol / L sulfuric acid, 0.2 mol / L to 0.5 mol / L phosphoric acid, and 0.1 g / L to 1 g / L aluminum sulfate.

9. The method for preparing a transfer mold according to claim 8, characterized in that, The step of performing a second anodic oxidation on the metal plate in a second electrolyte includes: The metal plate is immersed in a second electrolyte, wherein the third temperature T3 of the second electrolyte is in the range of 16℃ ≤ T3 ≤ 24℃; and The second anodizing is performed at a second voltage U2 of 60V≤U2≤100V.

10. The method for preparing a transfer mold according to claim 1, characterized in that, The process of enlarging the hole in the metal plate includes: The metal plate is immersed in a second etching solution to enlarge the holes, wherein the second etching solution comprises: 0.4 mol / L to 0.8 mol / L phosphoric acid and 0.1 mol / L to 0.5 mol / L nitric acid.

11. The method for preparing a transfer mold according to claim 10, characterized in that, Immersing the metal plate in a second etching solution to enlarge the holes includes: The metal plate is immersed in the second etching solution, and the hole is enlarged at a fourth temperature T4 of 60℃≤T4≤80℃.

12. The method for preparing a transfer mold according to claim 1, characterized in that, The metal plate is subjected to a second anodizing and hole enlargement process repeatedly.

13. The method for preparing a transfer mold according to any one of claims 1-12, characterized in that, The width of the first recessed portion is in the range of 40nm≤a1≤200nm; the depth h1 of the first recessed portion is in the range of 100nm≤h1≤500nm.

14. An embossing mold, characterized in that, The embossing mold is prepared by the method of preparing the transfer mold according to any one of claims 1-13, and is obtained by two transfers. The embossing mold includes a plurality of second recesses spaced apart on its surface. The plurality of first recesses have the same structure as the plurality of second recesses. The arrangement period d2 of the plurality of second recesses is in the range of d2≤200nm. The width a2 of the second recess is in the range of 40nm≤a2≤200nm. The depth h2 of the second recess is in the range of 100nm≤h2≤500nm.

15. A method for preparing a cover plate, characterized in that, The preparation method includes: Provide base materials; A photoresist layer is formed on the surface of the substrate; A textured structure is imprinted on the surface of the photoresist layer using the imprinting mold of claim 14, wherein the textured structure is complementary to the structure of the plurality of second recesses of the imprinting mold; and Dry etching is performed to obtain a cover plate, wherein the cover plate includes a plurality of protrusions spaced apart on its surface, the arrangement period d3 of the plurality of protrusions being in the range of d3≤200nm, and the plurality of protrusions being structurally complementary to the plurality of second recesses of the imprinting mold.

16. A cover plate, characterized in that, The cover plate includes a plurality of protrusions spaced apart on its surface, wherein the arrangement period d3 of the plurality of protrusions is in the range of d3≤200nm.

17. The cover plate according to claim 16, characterized in that, The width a3 of the protrusion is in the range of 40nm≤a3≤200nm.

18. The cover plate according to claim 16 or 17, characterized in that, The height h3 of the protrusion is in the range of 100nm≤h3≤500nm.

19. A terminal, characterized in that, include: The display screen has a display surface; The cover plate according to any one of claims 16-18, wherein the cover plate is stacked on the display surface of the display screen for protecting the display screen; as well as A processor, electrically connected to the display screen, is used to control the display screen to perform a display.

Images