Optical coating film, decorative film, cover plate and electronic equipment

Abstract

The invention provides an optical coating film, a decorative film, a cover plate and electronic equipment. The optical coating film comprises a low-folding layer, the low-folding layer comprises a Si-Me1-O composite material, and the Poisson ratio of oxide of Me1 is larger than that of silicon dioxide; the high-folding layer and the low-folding layer are arranged in a stacked mode, and the refractive index of the high-folding layer is larger than that of the low-folding layer. The optical coating film provided by the embodiment of the invention has relatively high toughness, and is not easy to crack when being subjected to an external force.

Description

Technical Field

[0001] The present application relates to the field of electronics, and in particular to an optical coating, a decorative film, a cover plate and an electronic device. Background Art

[0002] In order to make electronic devices (such as mobile phones, tablet computers, etc.) have a better appearance, optical coatings are usually set on the back cover of the electronic device, so that the back cover has higher brightness or a gorgeous color effect. However, the existing optical coatings have low toughness and high brittleness, and are prone to cracking when subjected to external forces such as bending or stretching. Summary of the invention

[0003] The embodiments of the present application provide an optical coating having high toughness and being less likely to break when subjected to external forces.

[0004] In a first aspect, an embodiment of the present application provides an optical coating, which includes:

[0005] A low-fold layer, the low-fold layer comprising a Si-Me1-O composite material, wherein the Poisson's ratio of the oxide of Me1 is greater than the Poisson's ratio of silicon dioxide; and

[0006] A high fold layer is stacked with the low fold layer, and the refractive index of the high fold layer is greater than the refractive index of the low fold layer.

[0007] In a second aspect, an embodiment of the present application provides a decorative film, the decorative film comprising:

[0008] a substrate layer; and

[0009] The optical coating described in the embodiment of the first aspect of the present application is arranged on one side of the substrate layer.

[0010] In a third aspect, an embodiment of the present application provides a cover plate, wherein the cover plate comprises:

[0011] Cover body;

[0012] an adhesive layer disposed on a surface of the cover body; and

[0013] The decorative film described in the second embodiment of the present application is arranged on the surface of the adhesive layer away from the cover body, and the substrate layer is located between the cover body and the optical coating.

[0014] In a fourth aspect, an embodiment of the present application provides an electronic device, comprising:

[0015] Display screen;

[0016] The cover plate according to the third aspect of the present application is arranged opposite to the display screen; and

[0017] A processor is located between the cover plate and the display screen, and the processor is electrically connected to the display screen to control the display screen to display.

[0018] The optical coating of the embodiment of the present application includes a low-fold layer and a high-fold layer. The low-fold layer includes a Si-Me1-O composite material, wherein the Poisson's ratio of the oxide of Me1 is greater than the Poisson's ratio of silicon dioxide; the high-fold layer is stacked with the low-fold layer, and the refractive index of the high-fold layer is greater than the refractive index of the low-fold layer. By using the Si-Me1-O composite material as the material of the low-fold layer, and making the Poisson's ratio of the oxide of Me1 greater than the Poisson's ratio of silicon dioxide, the low-fold layer has a higher Poisson's ratio compared to silicon dioxide, thereby having better toughness, higher bending resistance and tensile resistance, and the optical coating is less likely to break when subjected to external forces such as bending and stretching. In addition, when the optical coating is formed, the high-energy deposited particles cool instantly on the surface of the substrate layer. Due to differences in thermal expansion coefficients, optical coating growth defects, and changes in atomic gaps, stress is easily accumulated inside the optical coating, usually compressive stress. As the thickness of the optical coating deposition increases, the compressive stress gradually accumulates and increases. Excessive compressive stress leads to easy rupture during the bonding process of the optical coating. The low-fold layer of the present application has better toughness, so that the internal stress generated by the optical coating during the preparation process can be better reduced, so that the optical coating can be made thicker or have more layers, thereby achieving higher brightness, richer colors and better texture, and better meeting the requirements for differentiated appearance of electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a schematic diagram of the planar structure of an optical coating according to an embodiment of the present application.

[0021] Figure 2 It is the optical coating of the first embodiment of the present application. Figure 1 Schematic diagram of the cross-sectional structure in the AA direction.

[0022] Figure 3 The optical coating of the second embodiment of the present application is Figure 1 Schematic diagram of the cross-sectional structure in the AA direction.

[0023] Figure 4 The optical coating of the third embodiment of the present application is Figure 1 Schematic diagram of the cross-sectional structure in the AA direction.

[0024] Figure 5 The optical coating of the fourth embodiment of the present application is Figure 1 Schematic diagram of the cross-sectional structure in the AA direction.

[0025] Figure 6 It is a schematic diagram of the cross-sectional structure of the decorative film of the first embodiment of the present application.

[0026] Figure 7 It is a schematic diagram of the cross-sectional structure of the decorative film of the second embodiment of the present application.

[0027] Figure 8 It is a schematic cross-sectional structural diagram of a cover plate according to an embodiment of the present application.

[0028] Fig. 9 It is a schematic diagram of a process for preparing a cover plate according to an embodiment of the present application.

[0029] Fig.10 It is a schematic diagram of the cross-sectional structure of the cover plate of Example 1 and Example 2 of the present application.

[0030] Fig.11 It is a schematic diagram of the cross-sectional structure of the cover plate of Example 2 of the present application.

[0031] Fig.12 This is a picture of the cover plate of Example 1 of the present application after the bending resistance test.

[0032] Fig.13 This is a picture of the cover plate of Example 2 of the present application after the bending resistance test.

[0033] Fig.14 This is a picture of the cover plate of Example 3 of the present application after the bending resistance test.

[0034] Fig.15 This is a picture of the cover plate of Example 2 of the present application after the bending resistance test.

[0035] Fig.16 It is a schematic diagram of the structure of an electronic device according to an embodiment of the present application.

[0036] Fig.17 It is a schematic diagram of a partial exploded structure of an electronic device according to an embodiment of the present application.

[0037] Fig.18 It is a circuit block diagram of an electronic device according to an embodiment of the present application.

[0038] Description of reference numerals:

[0039] 100-optical coating, 10-low folding layer, 20-high folding layer, 30-buffer layer, 200-decorative film, 210-base material layer, 220-texture layer, 230-cover bottom layer, 300-cover plate, 310-cover body, 320-adhesive layer, 301-light-transmitting part, 500-electronic device, 510-display screen, 520-middle frame, 530-processor, 550-memory, 570-camera module. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0041] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0042] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0043] It should be noted that, for the convenience of explanation, in the embodiments of the present application, the same figure marks represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments.

[0044] In order to make electronic devices (such as mobile phones, tablets, etc.) have a better appearance, an optical coating is usually set on the back cover of the electronic device, so that the back cover has at least one of higher brightness, brilliant color effects, better texture, etc. However, the existing optical coating has low toughness and high brittleness, and is prone to cracking when subjected to external forces such as bending or stretching. Specifically, the optical coating is usually deposited on a substrate such as PET first, and then the substrate with the optical coating is bonded to the cover by an adhesive such as glue. When the cover is a 3D structure, the optical coating is subjected to bending or stretching during the bonding process, which makes the optical coating prone to cracking, reducing the preparation yield of the optical coating and the cover.

[0045] Figure 1 Schematic diagram of the planar structure of an optical coating 100 according to an embodiment of the present application. Figure 2 The optical coating 100 of the first embodiment of the present application is Figure 1 Schematic diagram of the cross-sectional structure in the AA direction. Figure 3 The optical coating 100 of the second embodiment of the present application is Figure 1 Schematic diagram of the cross-sectional structure in the AA direction.

[0046] See also Figures 1 to 3 The embodiment of the present application provides an optical coating 100, which includes a low-fold layer 10 and a high-fold layer 20. The low-fold layer 10 includes a Si-Me1-O composite material, wherein the Poisson's ratio of the oxide of Me1 is greater than the Poisson's ratio of silicon dioxide; the high-fold layer 20 is stacked with the low-fold layer 10, and the refractive index of the high-fold layer 20 is greater than the refractive index of the low-fold layer 10.

[0047] The term "Poisson's ratio" refers to the ratio of the absolute value of the transverse normal strain to the axial normal strain when the material is subjected to unidirectional tension or compression. It is also called the transverse deformation coefficient. It is an elastic constant that reflects the transverse deformation of the material.

[0048] The optical coating 100 of the present application can be used as a decorative film for the cover of an electronic device to increase the brightness of the cover of the electronic device, or to make the cover of the electronic device have a colorful effect, thereby improving the appearance of the electronic device. The cover of the present application may be, but is not limited to, at least one of the back cover, decorative parts, etc. of the electronic device. In the embodiments of the present application, the cover of the electronic device is illustrated and described by taking the back cover of the electronic device, such as the back cover of the battery, as an example, and should not be understood as a limitation on the optical coating 100 and the cover of the embodiment of the present application. Optionally, the cover may be, but is not limited to, at least one of a 2D structure, a 2.5D structure, a 3D structure, etc. The electronic device may be, but is not limited to, a portable electronic device such as a mobile phone, a tablet computer, a laptop computer, a desktop computer, a smart bracelet, a smart watch, an e-reader, a game console, etc.

[0049] Optionally, the number of the low fold layers 10 may be one or more. When the number of the low fold layers 10 is multiple, the multiple low fold layers 10 are arranged in sequence and at intervals, and a high fold layer 20 is arranged between any two adjacent low fold layers 10 .

[0050] The term "plurality" means greater than or equal to two.

[0051] Optionally, the number of the high fold layers 20 may be one or more. When the number of the high fold layers 20 is multiple, the multiple high fold layers 20 are sequentially arranged at intervals, and a low fold layer 10 is arranged between any two adjacent high fold layers 20 .

[0052] Understandably, if Figure 3As shown, when the number of the high folding layers 20 and the number of the low folding layers 10 are both multiple layers, the high folding layers 20 and the low folding layers 10 are alternately stacked in sequence.

[0053] The optical coating 100 of the embodiment of the present application includes a low-fold layer 10 and a high-fold layer 20. The low-fold layer 10 includes a Si-Me1-O composite material, wherein the Poisson's ratio of the oxide of Me1 is greater than the Poisson's ratio of silicon dioxide; the high-fold layer 20 is stacked with the low-fold layer 10, and the refractive index of the high-fold layer 20 is greater than the refractive index of the low-fold layer 10. By using the Si-Me1-O composite material as the material of the low-fold layer 10, and making the Poisson's ratio of the oxide of Me1 greater than the Poisson's ratio of silicon dioxide, the low-fold layer 10 has a higher Poisson's ratio compared to silicon dioxide, and thus has better toughness, higher bending resistance and tensile resistance, and the optical coating 100 is less likely to break when subjected to external forces such as bending and stretching. In addition, when the optical coating 100 is formed, the high-energy deposited particles are instantly cooled on the surface of the substrate layer. Due to differences in thermal expansion coefficients, growth defects of the optical coating 100, and changes in atomic spacing, stress is easily accumulated inside the optical coating 100, usually compressive stress. As the deposition thickness of the optical coating 100 increases, the compressive stress gradually accumulates and increases. Excessive compressive stress causes the optical coating 100 to easily break during the bonding process. The low-fold layer 10 of the present application has better toughness, so that the internal stress generated by the optical coating 100 during the preparation process can be better reduced, so that the optical coating 100 can be made thicker or have more layers, so as to achieve higher brightness, richer colors and better texture, and better meet the requirements of appearance differentiation of electronic devices.

[0054] Optionally, the thickness of the optical coating 100 ranges from 200nm to 900nm. Specifically, the thickness of the optical coating 100 may be, but is not limited to, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, 550nm, 600nm, 650nm, 700nm, 750nm, 800nm, 850nm, 900nm, etc. If the thickness of the optical coating 100 is too thin, it is not conducive to the realization of the functions of the optical coating 100 such as highlight, color, and dazzling; if the thickness of the optical coating 100 is too thick, the optical coating 100 is prone to accumulate stress, thereby reducing the bending resistance of the optical coating 100, and it is easy to break when subjected to bending or tensile force.

[0055] In the embodiments of the present application, when a numerical value range from a to b is involved, unless otherwise specified, it means that the numerical value can be any numerical value between a and b, including the endpoint numerical value a and the endpoint numerical value b.

[0056] In some embodiments, the Poisson's ratio v1 of the oxide of Me1 is in the range of: v1 ≥ 0.2.

[0057] Furthermore, the Poisson's ratio v1 of the oxide of Me1 is in the range of 0.2≤v1≤0.45.

[0058] Specifically, the Poisson's ratio v1 of the oxide of Me1 may be, but is not limited to, 0.2, 0.22, 0.24, 0.26, 0.28, 0.3, 0.32, 0.34, 0.35, 0.36, 0.37, 0.38, 0.40, 0.42, 0.44, 0.45, etc.

[0059] In this embodiment, if the Poisson's ratio v1 of the oxide of Me1 is too small, the improvement of the toughness, bending resistance and tensile strength of the low-folding layer 10 is limited; if the Poisson's ratio v1 of the oxide of Me1 is too large, the preparation cost of the low-folding layer 10 is increased.

[0060] In some embodiments, in the Si-Me1-O composite material, the mass fraction of the Me1 element ranges from 5% to 40%.

[0061] Specifically, in the Si-Me1-O composite material, the mass fraction of the Me1 element can be, but is not limited to, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, etc.

[0062] In this embodiment, if the mass fraction of the Me1 element in the Si-Me1-O composite material is too low, the improvement of the Poisson's ratio of the low-fold layer 10 is limited, and it is difficult to effectively improve the toughness of the low-fold layer 10, and the improvement of the bending resistance and tensile resistance of the optical coating 100 is limited; if the mass fraction of the Me1 element in the Si-Me1-O composite material is too high, then since the oxide of Me1 has a higher refractive index than silicon dioxide, the mass fraction of the Me1 element is too high, which will make the refractive index of the low-fold layer 10 too high, and the refractive index difference between the low-fold layer 10 and the high-fold layer 20 is too small, which is not conducive to the realization of the function of the optical coating 100.

[0063] In some embodiments, in the Si-Me1-O composite material, the mass fraction of the Si element (ie, silicon element) ranges from 19% to 42%.

[0064] Specifically, in the Si-Me1-O composite material, the mass fraction of Si element can be but is not limited to 19%, 20%, 23%, 25%, 28%, 30%, 33%, 35%, 38%, 40%, 42%, etc.

[0065] In this embodiment, if the mass fraction of Si element in the Si-Me1-O composite material is too low, the refractive index of the low-fold layer 10 is increased, so that the refractive index difference between the low-fold layer 10 and the high-fold layer 20 is too small, which is not conducive to the realization of the function of the optical coating 100; if the mass fraction of Si element in the Si-Me1-O composite material is too high, the toughness of the low-fold layer 10 is reduced, which is not conducive to the improvement of the bending resistance and tensile resistance of the optical coating 100.

[0066] Optionally, the Si—Me1-O composite material includes, by mass fraction, 5% to 40% of Me1 element, 19% to 42% of Si element, and the balance of oxygen element.

[0067] In some embodiments, Me1 is a first metal element, and the first metal element includes at least one of niobium (Nb), aluminum (Al), titanium (Ti), zirconium (Zr), zinc (Zn), cerium (Ce), chromium (Cr), gallium (Ga), tin (Sn), indium (In), tantalum (Ta), yttrium (Y), etc. The oxides of these metal elements have a higher Poisson's ratio, and when added to the low-fold layer 10, the Poisson's ratio of the low-fold layer 10 can be better improved, thereby improving the toughness, bending resistance and tensile strength of the low-fold layer 10, so that the optical coating 100 is less likely to break when subjected to external forces such as bending and stretching. In addition, the oxides of these metal elements have good chemical stability and good resistance to high temperature, high humidity, and acid and alkali.

[0068] Optionally, the refractive index n1 of the low-fold layer 10 is in the range of 1.46≤n1≤1.9. Specifically, the refractive index n1 of the low-fold layer 10 may be, but is not limited to, 1.46, 1.48, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75, 1.80, 1.85, 1.9, etc. If the refractive index of the low-fold layer 10 is too low, the content of Me1 in the low-fold layer 10 is too small, which is not conducive to improving the toughness of the low-fold layer 10 and reducing the bending resistance and tensile resistance of the optical coating 100; if the refractive index of the low-fold layer 10 is too high, the refractive index difference between the low-fold layer 10 and the high-fold layer 20 is too small, which is not conducive to the realization of the function of the optical coating 100.

[0069] Optionally, the refractive index of the low-fold layer 10 for light with a wavelength of 550 nm is in a range of 1.46 to 1.9.

[0070] Optionally, the thickness of the low-fold layer 10 ranges from 3nm to 200nm. Specifically, the thickness of the low-fold layer 10 may be, but is not limited to, 3nm, 5nm, 10nm, 20nm, 30nm, 50nm, 80nm, 100nm, 130nm, 150nm, 180nm, 200nm, etc. If the thickness of the low-fold layer 10 is too thin, it is not conducive to the precise control of the thickness of the low-fold layer 10, and the uniformity of the thickness of the low-fold layer 10 is reduced, thereby affecting the uniformity of the reflection and color effects of the optical coating 100; if the thickness of the low-fold layer 10 is too thick, the low-fold layer 10 is prone to accumulate stress during the preparation process, so that the optical coating 100 is prone to rupture when subjected to force.

[0071] In some embodiments, the high-fold layer 20 includes an R-Me2-O composite material, wherein the R element includes at least one of niobium, titanium, and tantalum, and the R element is different from the Me2 element.

[0072] In this embodiment, the high-fold layer 20 includes an R-Me2-O composite material, and the R element includes at least one of niobium, titanium, and tantalum. The use of these metal elements can make the high-fold layer 20 have a higher refractive index, so that the function of the optical coating 100 can be better realized; in addition, the high-fold layer 20 has a higher Poisson's ratio, so it has better toughness, higher bending resistance and tensile resistance, and the optical coating 100 is less likely to break when subjected to external forces such as bending and stretching.

[0073] Optionally, the Poisson's ratio of the oxide of Me2 is greater than the Poisson's ratio of the oxide of R. In this embodiment, the Poisson's ratio of the oxide of Me2 is greater than the Poisson's ratio of the oxide of R, which can better improve the Poisson's ratio of the high-fold layer 20, so that the high-fold layer 20 has better toughness, higher bending resistance and tensile resistance, and the optical coating 100 is less likely to break when subjected to external forces such as bending and stretching.

[0074] In some embodiments, the Poisson's ratio v2 of the oxide of Me2 is in the range of: v2 ≥ 0.25.

[0075] Furthermore, the Poisson's ratio v2 of the oxide of Me2 is in the range of 0.25≤v2≤0.45.

[0076] Specifically, the Poisson's ratio v2 of the oxide of Me2 can be, but is not limited to, 0.25, 0.26, 0.28, 0.3, 0.32, 0.34, 0.35, 0.36, 0.37, 0.38, 0.40, 0.42, 0.44, 0.45, etc.

[0077] In this embodiment, if the Poisson's ratio v2 of the oxide of Me2 is too small, the improvement of the toughness, bending resistance and tensile strength of the high folding layer 20 is limited; if the Poisson's ratio v2 of the oxide of Me2 is too large, the preparation cost of the high folding layer 20 is increased.

[0078] In some embodiments, in the R-Me2-O composite material, the mass fraction of Me2 element ranges from 2% to 25%.

[0079] Specifically, in the R-Me2-O composite material, the mass fraction of the Me2 element can be but is not limited to 2%, 5%, 8%, 10%, 13%, 15%, 18%, 20%, 23%, 25%, etc.

[0080] In this embodiment, if the mass fraction of the Me2 element in the R-Me2-O composite material is too low, the improvement of the Poisson's ratio of the high-fold layer 20 is limited, and it is difficult to effectively improve the toughness of the high-fold layer 20, and the improvement of the bending resistance and tensile resistance of the optical coating 100 is limited; as the mass fraction of the Me2 element in the R-Me2-O composite material increases, the Poisson's ratio of the high-fold layer 20 can be improved, but when the mass fraction of the Me2 element in the R-Me2-O composite material is too high, the refractive index of the high-fold layer 20 decreases, so that the refractive index difference between the low-fold layer 10 and the high-fold layer 20 is too small, which is not conducive to the realization of the function of the optical coating 100.

[0081] In some embodiments, in the R-Me2-O composite material, the mass fraction of the R element ranges from 48% to 70%.

[0082] Specifically, in the R-Me2-O composite material, the mass fraction of the R element can be but is not limited to 48%, 50%, 52%, 54%, 56%, 58%, 60%, 62%, 64%, 66%, 68%, 70%, etc.

[0083] In this embodiment, if the mass fraction of the R element in the R-Me2-O composite material is too low, the refractive index of the high-fold layer 20 is reduced, so that the refractive index difference between the low-fold layer 10 and the high-fold layer 20 is too small, which is not conducive to the realization of the function of the optical coating 100; if the mass fraction of the R element in the R-Me2-O composite material is too high, it is not conducive to the improvement of the Poisson's ratio of the high-fold layer 20, and it is difficult to effectively improve the toughness of the high-fold layer 20, which is not conducive to the improvement of the bending resistance and tensile resistance of the optical coating 100.

[0084] Optionally, the R-Me2-O composite material includes, by mass fraction, 2% to 25% of the Me1 element, 48% to 70% of the R element, and the balance of oxygen element.

[0085] In some embodiments, Me2 is a second metal element, and the second metal element includes at least one of zirconium (Zr), zinc (Zn), cerium (Ce), chromium (Cr), gallium (Ga), tin (Sn), indium (In), tantalum (Ta), yttrium (Y), etc. The oxides of these metal elements have a higher Poisson's ratio, and when added to the high-folding layer 20, the Poisson's ratio of the high-folding layer 20 can be better improved, thereby improving the toughness, bending resistance and tensile strength of the high-folding layer 20, so that the optical coating 100 is less likely to break when subjected to external forces such as bending and stretching. In addition, the oxides of these metal elements have good chemical stability and good resistance to high temperature, high humidity, and acid and alkali.

[0086] Optionally, the refractive index n2 of the high fold layer 20 is in the range of 1.95≤n2≤2.40. Specifically, the refractive index n2 of the high fold layer 20 may be, but is not limited to, 1.95, 2.00, 2.05, 2.10, 2.15, 2.20, 2.25, 2.30, 2.35, 2.40, etc. If the refractive index of the high fold layer 20 is too low, the refractive index difference between the high fold layer 20 and the low fold layer 10 is too small, which is not conducive to the realization of the function of the optical coating 100; if the refractive index of the high fold layer 20 is too high, the content of Me2 in the high fold layer 20 is too small, which is not conducive to improving the toughness of the high fold layer 20, and reduces the bending resistance and tensile resistance of the optical coating 100.

[0087] Optionally, the refractive index of the high-fold layer 20 for light with a wavelength of 550 nm is in a range of 1.95 to 2.40.

[0088] Optionally, the thickness of the high fold layer 20 ranges from 3nm to 200nm. Specifically, the thickness of the high fold layer 20 may be, but is not limited to, 3nm, 5nm, 10nm, 20nm, 30nm, 50nm, 80nm, 100nm, 130nm, 150nm, 180nm, 200nm, etc. If the thickness of the high fold layer 20 is too thin, it is not conducive to the precise control of the thickness of the high fold layer 20, and the uniformity of the thickness of the high fold layer 20 is reduced, thereby affecting the uniformity of the reflection and color effects of the optical coating 100; if the thickness of the high fold layer 20 is too thick, the high fold layer 20 is prone to accumulate stress during the preparation process, so that the optical coating 100 is prone to rupture when subjected to force.

[0089] Figure 4 The optical coating 100 of the third embodiment of the present application is Figure 1 Schematic diagram of the cross-sectional structure in the AA direction. Figure 5 The optical coating 100 of the fourth embodiment of the present application is Figure 1 Schematic diagram of the cross-sectional structure in the AA direction.

[0090] See also Figure 4 and Figure 5 In some embodiments, the optical coating 100 further includes a buffer layer 30, wherein the buffer layer 30 is located between the high fold layer 20 and the low fold layer 10, and the buffer layer 30 includes Si element or Si-Me3 composite material, and the Poisson's ratio of the Me3 element is greater than the Poisson's ratio of the Si element.

[0091] Optionally, the number of the buffer layer 30 may be one or more layers. When the number of either the high fold layer 20 or the low fold layer 10 is multiple layers, the number of the buffer layer 30 is multiple layers, the multiple buffer layers 30 are arranged at intervals, and two adjacent buffer layers 30 are separated by the high fold layer 20 or the low fold layer 10. In other words, a high fold layer 20 or a low fold layer 10 is provided between two adjacent buffer layers 30.

[0092] It is understandable that the buffer layer 30 may only include silicon. In other words, the buffer layer 30 may not contain Me3 elements.

[0093] It should be noted that when the buffer layer 30 only includes silicon, the silicon is α-Si (ie, amorphous silicon).

[0094] In this embodiment, by arranging the buffer layer 30 between the high fold layer 20 and the low fold layer 10, the interlayer stress between the high fold layer 20 and the low fold layer 10 can be well buffered, thereby reducing the overall stress of the optical coating 100, so that the optical coating 100 can be made thicker (or have more layers, so as to achieve higher brightness, richer colors and better texture, and better meet the requirements of appearance differentiation of electronic equipment; in addition, the optical coating 100 is not easy to break when subjected to external force. Furthermore, the buffer layer 30 includes Si element or Si-Me3 composite material, Si element can improve the bonding force between the buffer layer 30 and the low fold layer 10, and Me3 element can improve the bonding force between the buffer layer 30 and the high fold layer 20 and the low fold layer 10, so that the high fold layer 20, the buffer layer 30 and the low fold layer 10 have good bonding force. Furthermore, the Poisson's ratio of the Me3 element is greater than the Poisson's ratio of the silicon element, so that the buffer layer 30 has a higher Poisson's ratio, thereby having better toughness, and can play a better role in buffering and absorbing stress.

[0095] In a specific embodiment, by adopting the technical solution of the application, the upper limit of the thickness of the optical coating 100 can be increased from 500 nm to more than 700 nm.

[0096] In some embodiments, the Poisson's ratio v3 of the Si-Me3 composite material is in the range of 0.25≤v3≤0.4.

[0097] Specifically, the Poisson's ratio v3 of the Si-Me3 composite material may be, but is not limited to, 0.25, 0.26, 0.28, 0.3, 0.32, 0.34, 0.36, 0.38, 0.4, etc.

[0098] In this embodiment, if the Poisson's ratio v3 of the Si-Me3 composite material is too low, it is not conducive to buffering the interlayer stress between the high fold layer 20 and the low fold layer 10; if the Poisson's ratio v3 of the Si-Me3 composite material is too high, the preparation cost of the buffer layer 30 is increased.

[0099] Optionally, the range of the Poisson's ratio v4 of the Me3 element is: 0.25≤v4≤0.45. Specifically, the Poisson's ratio v4 of the Me3 element may be, but is not limited to, 0.25, 0.26, 0.28, 0.3, 0.32, 0.34, 0.36, 0.38, 0.4, 0.42, 0.45, etc. In this embodiment, if the Poisson's ratio v4 of the Me3 element is too low, it is not conducive to buffering the interlayer stress between the high fold layer 20 and the low fold layer 10; if the Poisson's ratio v4 of the Me3 element is too high, the preparation cost of the buffer layer 30 is increased.

[0100] In some embodiments, in the buffer layer 30 , the mass fraction of the Me3 element ranges from 0% to 50%, and the mass fraction of the Si element ranges from 50% to 100%.

[0101] Specifically, the mass fraction of the Me3 element in the buffer layer 30 may be, but is not limited to, 0%, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc. If the mass fraction of the Me3 element in the buffer layer 30 is too low, the toughness of the buffer layer 30 is low, which is not conducive to buffering the stress between the high fold layer 20 and the low fold layer 10; if the mass fraction of the Me3 element in the buffer layer 30 is too high, the buffer layer 30 has a higher Poisson's ratio and better buffering effect, but the cost of the buffer layer 30 is increased.

[0102] Specifically, the mass fraction of the Si element in the buffer layer 30 may be, but is not limited to, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, etc. If the mass fraction of the Si element in the buffer layer 30 is too low, the buffer layer 30 has a higher Poisson's ratio and better buffering effect, but the cost of the buffer layer 30 is increased.

[0103] In some embodiments, the thickness of the buffer layer 30 is less than or equal to 2 nm. Specifically, the thickness of the buffer layer 30 may be, but is not limited to, 0.1 nm, 0.2 nm, 0.3 nm, 0.5 nm, 0.8 nm, 1.0 nm, 1.2 nm, 1.4 nm, 1.6 nm, 1.8 nm, 2 nm, etc. If the thickness of the buffer layer 30 is too thin, the buffering between the high fold layer 20 and the low fold layer 10 may be uneven; Si-Me3 is an absorbing material, and if the thickness of the buffer layer 30 is too thick, the absorption of the optical coating 100 may be too large, making the optical coating 100 have the risk of being conductive. In addition, if the thickness of the buffer layer 30 is too thick, it may affect the performance of the optical coating 100 and increase the complexity of the design of the optical coating 100.

[0104] Furthermore, the thickness of the buffer layer 30 is in the range of 0.3 nm to 2 nm, which can make the thickness of the buffer layer 30 more uniform and reduce the risk of electrical conduction.

[0105] In some embodiments, Me3 is a third metal element, and the third metal element includes at least one of niobium (Nb), zirconium (Zr), zinc (Zn), gallium (Ga), tin (Sn), indium (In), tantalum (Ta), yttrium (Y), aluminum (Al), titanium (Ti), chromium (Cr), etc.

[0106] It should be noted that Me3 and Me1 may be the same or different. When Me3 and Me1 are the same, the bonding force between the buffer layer 30 and the low fold layer 10 can be better improved. Me3 and Me2 may be the same or different. When Me3 and Me2 are the same, the bonding force between the buffer layer 30 and the high fold layer 20 can be better improved.

[0107] In this embodiment, these metal elements are used as Me3, and these metal elements are commonly used metal elements in the high fold layer 20 and the low fold layer 10, so that the bonding force between the buffer layer 30 and the high fold layer 20 and the low fold layer 10 can be improved. In addition, the oxides of these metal elements have a higher Poisson's ratio, and adding them to the buffer layer 30 can better improve the Poisson's ratio of the buffer layer 30, thereby improving the buffer stress capacity of the buffer layer 30. Furthermore, the oxides of these metal elements have good chemical stability, and have good resistance to high temperature, high humidity, acid and alkali.

[0108] Optionally, the refractive index n3 of the buffer layer 30 is in the range of 1.8≤n3≤3.45. Specifically, the refractive index n3 of the buffer layer 30 may be, but is not limited to, 1.8, 1.9, 1.95, 2.00, 2.05, 2.10, 2.15, 2.20, 2.25, 2.30, 2.35, 2.40, 2.5, 2.6, 2.7, 2.8, 2.9, 3.1, 3.2, 3.3, 3.4, 3.45, etc.

[0109] Optionally, the refractive index of the buffer layer 30 for light with a wavelength of 550 nm is in a range of 1.8 to 3.45.

[0110] Figure 6 Schematic diagram of the cross-sectional structure of the decorative film 200 according to the first embodiment of the present application.

[0111] See also Figure 6 The embodiment of the present application further provides a decorative film 200 , which includes a substrate layer 210 and the optical coating 100 described in the embodiment of the present application, and the optical coating 100 is disposed on one side of the substrate layer 210 .

[0112] For detailed description of other aspects of the optical coating 100 , please refer to the description of the corresponding parts of the above embodiments, which will not be repeated here.

[0113] It should be noted that, in the present application, “arranged on one side of a certain element” can mean arranged on the surface of the element; or arranged opposite to the element and spaced apart, with other elements arranged between the element.

[0114] The decorative film 200 of the embodiment of the present application includes a substrate layer 210 and an optical coating 100, and the optical coating 100 includes a low-fold layer 10 and a high-fold layer 20. The low-fold layer 10 includes a Si-Me1-O composite material, wherein the Poisson's ratio of the oxide of Me1 is greater than the Poisson's ratio of silicon dioxide; the high-fold layer 20 is stacked with the low-fold layer 10, and the refractive index of the high-fold layer 20 is greater than the refractive index of the low-fold layer 10. By using the Si-Me1-O composite material as the material of the low-fold layer 10, and making the Poisson's ratio of the oxide of Me1 greater than the Poisson's ratio of silicon dioxide, the low-fold layer 10 has a higher Poisson's ratio compared to silicon dioxide, and thus has better toughness, higher bending resistance and tensile resistance, and the optical coating 100 is less likely to break when subjected to external forces such as bending and stretching. In addition, when the optical coating 100 is formed, the high-energy deposited particles are instantly cooled on the surface of the substrate layer. Due to differences in thermal expansion coefficients, growth defects of the optical coating 100, and changes in atomic spacing, stress is easily accumulated inside the optical coating 100, usually compressive stress. As the deposition thickness of the optical coating 100 increases, the compressive stress gradually accumulates and increases. Excessive compressive stress causes the optical coating 100 to easily break during the bonding process. The low-fold layer 10 of the present application has better toughness, so that the internal stress generated by the optical coating 100 during the preparation process can be better reduced, so that the optical coating 100 can be made thicker or have more layers, so as to achieve higher brightness, richer colors and better texture, and better meet the requirements of appearance differentiation of electronic devices.

[0115] Optionally, the material of the substrate layer 210 may be, but is not limited to, at least one of polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), and the like.

[0116] Figure 7 Schematic diagram of the cross-sectional structure of the decorative film 200 according to the second embodiment of the present application.

[0117] See also Figure 7 Optionally, the decorative film 200 further includes a texture layer 220 and a cover bottom layer 230, wherein the texture layer 220 is located between the substrate layer 210 and the optical coating 100, and is used to make the decorative film 200 have a texture effect; the cover bottom layer 230 is arranged on the surface of the optical coating 100 away from the substrate layer 210, and is used to shield the electronic components on the side of the cover bottom layer 230 away from the substrate layer 210.

[0118] Optionally, the texture layer 220 has a texture structure. The texture layer 220 is a photocurable texture layer 220, such as an ultraviolet light-curable texture layer 220 (UV texture layer 220). Optionally, the texture layer 220 is formed by transferring a photocurable glue (such as UV glue) and then photocuring, for example, after UV glue is transferred to the surface of the substrate layer 210, the photocurable texture layer 220 is formed by photocuring. Optionally, the thickness of the texture layer 220 is 5 μm to 15 μm, specifically, it can be but not limited to 5 μm, 6 μm, 8 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, etc. When the thickness of the texture layer 220 is too thin, it is not conducive to the formation of the texture structure on the texture layer 220. When the thickness of the texture layer 220 is too thick, the thickness of the decorative film 200 is increased. When applied to electronic devices, the thickness and weight of the electronic devices are increased, affecting the feel and the user experience is not good.

[0119] Optionally, the cover bottom layer 230 may be, but is not limited to, a light-shielding ink that absorbs or reflects light. Optionally, the cover bottom layer 230 may be black, white or gray. The cover bottom layer 230 is used to prevent the hardened layer side of the cover plate from exposing the components inside the electronic device when the cover plate is applied to the electronic device. Optionally, the thickness of the cover bottom layer 230 is 5 μm to 20 μm, specifically, the thickness of the cover bottom layer 230 may be, but is not limited to, 5 μm, 8 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, etc. Optionally, the cover bottom layer 230 may be a layer or a plurality of layers, for example, 2 layers, 3 layers, 4 layers, or 5 layers are stacked. When the cover bottom layer 230 is a plurality of layers, it has a better shielding effect than a layer.

[0120] Figure 8 Schematic diagram of the cross-sectional structure of the cover plate 300 according to an embodiment of the present application.

[0121] See also Figure 8 The embodiment of the present application further provides a cover plate 300, the cover plate 300 comprises a cover body 310, an adhesive layer 320 and the decorative film 200 described in the embodiment of the present application. The adhesive layer 320 is disposed on the surface of the cover body 310; the decorative film 200 is disposed on the surface of the adhesive layer 320 away from the cover body 310, and the substrate layer 210 is located between the cover body 310 and the optical coating 100.

[0122] It can be understood that the adhesive layer 320 is used to adhere the decoration film 200 to the cover body 310 .

[0123] Optionally, the adhesive layer 320 may be, but is not limited to, optical adhesive (OCA adhesive for short).

[0124] For detailed description of other aspects of the decorative film 200 , please refer to the description of the corresponding parts of the above embodiment, which will not be repeated here.

[0125] The cover plate 300 of the embodiment of the present application may be a rear cover plate 300 of an electronic device, a decorative piece, etc. Optionally, the electronic device may be, but is not limited to, a portable electronic device such as a mobile phone, a tablet computer, a laptop computer, a desktop computer, a smart bracelet, a smart watch, an e-reader, a game console, etc.

[0126] It should be noted that the cover body 310 and the optical coating film 100 are stacked.

[0127] The cover plate 300 of the embodiment of the present application includes a cover body 310 and an optical coating 100, and the optical coating 100 includes a low-fold layer 10 and a high-fold layer 20. The low-fold layer 10 includes a Si-Me1-O composite material, wherein the Poisson's ratio of the oxide of Me1 is greater than the Poisson's ratio of silicon dioxide; the high-fold layer 20 is stacked with the low-fold layer 10, and the refractive index of the high-fold layer 20 is greater than the refractive index of the low-fold layer 10. By using the Si-Me1-O composite material as the material of the low-fold layer 10, and making the Poisson's ratio of the oxide of Me1 greater than the Poisson's ratio of silicon dioxide, the low-fold layer 10 has a higher Poisson's ratio compared to silicon dioxide, and thus has better toughness, higher bending resistance and tensile resistance, and the optical coating 100 is less likely to break when subjected to external forces such as bending and stretching. In addition, when the optical coating 100 is formed, the high-energy deposited particles are instantly cooled on the surface of the substrate layer. Due to differences in thermal expansion coefficients, growth defects of the optical coating 100, and changes in atomic spacing, stress is easily accumulated inside the optical coating 100, usually compressive stress. As the deposition thickness of the optical coating 100 increases, the compressive stress gradually accumulates and increases. Excessive compressive stress causes the optical coating 100 to easily break during the bonding process. The low-fold layer 10 of the present application has better toughness, so that the internal stress generated by the optical coating 100 during the preparation process can be better reduced, so that the optical coating 100 can be made thicker or have more layers, so as to achieve higher brightness, richer colors and better texture, and better meet the requirements of appearance differentiation of electronic devices.

[0128] Optionally, the material of the cover body 310 may be but is not limited to at least one of glass, sapphire, ceramic, resin, fiberglass board, etc.

[0129] Optionally, the thickness of the cover body 310 is 0.3 mm to 1 mm. Specifically, the thickness of the cover body 310 may be, but is not limited to, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc. When the cover body 310 is too thin, it cannot play a good supporting and protective role, and the mechanical strength cannot meet the requirements of the electronic device cover 300. When the cover body 310 is too thick, the weight of the electronic device is increased, the feel of the electronic device is affected, and the user experience is not good.

[0130] The cover plate 300 of the embodiment of the present application can be prepared by the method described in the following embodiments of the present application. In addition, it can also be prepared by other methods. The preparation method of the embodiment of the present application is only one or more preparation methods of the cover plate 300 of the present application and should not be understood as a limitation on the cover plate 300 provided by the embodiment of the present application.

[0131] Fig. 9 3 is a schematic flow chart of a method for preparing a cover plate 300 according to an embodiment of the present application.

[0132] See also Fig. 9 The present application also provides a method for preparing a cover plate 300, the method comprising:

[0133] S401, providing a substrate layer 210;

[0134] Optionally, the substrate layer 210 may be, but is not limited to, at least one of a PET layer, a PC layer, a PMMA layer, and the like.

[0135] S402, forming a texture layer 220 on the substrate layer 210;

[0136] Optionally, UV glue is coated on the surface of the substrate layer 210 and light-cured to form a stacked substrate layer 210 / texture layer 220 .

[0137] S403, forming an optical coating 100 on the surface of the texture layer 220 away from the substrate layer 210;

[0138] Optionally, the substrate layer 210 with the texture layer 220 is placed in a sputtering coating device and evacuated to a pressure lower than 0.003 Pa. A low-energy plasma is used to clean the surface of the texture layer 220 away from the substrate layer 210 to improve the activity of the surface of the texture layer 220 away from the substrate layer 210, thereby improving the adhesion of the optical coating 100 on the texture layer 220; optionally, the cleaning time can be 2 minutes to 5 minutes, for example, but not limited to 2 minutes, 3 minutes, 4 minutes, 5 minutes, etc. A target material is provided, and the optical coating 100 is plated on the surface of the texture layer 220 away from the substrate layer 210. After the coating is completed, the sputtering coating device breaks the vacuum and removes the decorative film 200.

[0139] Optionally, the coating process may be, but is not limited to, at least one of an electron beam thermal evaporation coating process, a sputtering coating process, and the like.

[0140] Optionally, before coating, the substrate layer 210 having the texture layer 220 and the carrier are baked at a temperature of 60°C to 80°C (e.g., 60°C, 65°C, 70°C, 75°C, 80°C) for 20 min to 40 min to remove moisture on the substrate layer 210 having the texture layer 220 and the carrier.

[0141] Optionally, the target material of the low-fold layer 10 may be a Si-Me1 target material. For detailed description of other aspects of Me1, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here.

[0142] Optionally, the Si-Me1 target can be but is not limited to at least one of a Si-Nb-Zn target, a Si-Nb-Y target, a Si-Nb target, a Si-Zn target, a Si-Al target, a Si-Ti target, a Si-Zr target, a Si-Ce target, a Si-Cr target, a Si-Ga target, a Si-Sn target, a Si-In target, a Si-Ta target, a Si-Y target, etc.

[0143] In a specific embodiment, the Si—Nb—Zn target includes 80% Si, 10% Nb, and 10% Zn by mass.

[0144] In another specific embodiment, the Si—Nb—Y target includes 80% Si, 10% Nb, and 10% Y by mass.

[0145] Optionally, the target material of the high folding layer 20 may be an R-Me2 target material. For detailed description of other aspects of Me2, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here.

[0146] Optionally, the target material of the R-Me2 target can be but is not limited to at least one of Nb-Zn target, Nb-Zr target, Nb-Ce target, Nb-Cr target, Nb-Ga target, Nb-Sn target, Nb-In target, Nb-Ta target, Nb-Y target, Ti-Zn target, Ti-Zr target, Ti-Ce target, Ti-Cr target, Ti-Ga target, Ti-Sn target, Ti-In target, Ti-Ta target, Ti-Y target, Ta-Zn target, Ta-Zr target, Ta-Ce target, Ta-Cr target, Ta-Ga target, Ta-Sn target, Ta-In target, Ta-Y target and the like.

[0147] In a specific embodiment, the Nb—Zn target includes 85% Nb and 15% Zn by mass.

[0148] In yet another specific embodiment, the Nb—Y target includes 85% Nb and 15% Y by mass.

[0149] Optionally, the target material of the buffer layer 30 may be a Si-Me3 target material. For detailed description of other aspects of Me3, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here.

[0150] Optionally, the Si-Me3 target may be but is not limited to at least one of a Si-Nb-Zn target, a Si-Nb target, a Si-Zr target, a Si-Zn target, a Si-Ga target, a Si-Sn target, a Si-In target, a Si-Ta target, a Si-Y target, a Si-Al target, a Si-Ti target, a Si-Cr target, etc.

[0151] In a specific embodiment, the Si—Nb—Zn target includes 80% Si, 10% Nb, and 10% Zn by mass.

[0152] S404, forming a cover layer 230 on the surface of the optical coating 100 away from the texture layer 220 to obtain a decorative film 200;

[0153] Optionally, a light-shielding ink is used to spray a layer of ink on the surface of the optical coating 100 away from the texture layer 220 , and then cured to form the cover layer 230 .

[0154] S405, providing a cover body 310 and an adhesive; and

[0155] For detailed description of other aspects of the cover body 310, please refer to the description of the corresponding parts of the above embodiment, which will not be repeated here.

[0156] Optionally, the adhesive may be, but is not limited to, optical adhesive.

[0157] S406 , the decorative film 200 is bonded to the surface of the cover body 310 by an adhesive, and the adhesive is cured to form an adhesive layer 320 , thereby obtaining the cover plate 300 .

[0158] Optionally, the decorative film 200 is cut and subjected to processes such as lamination, degassing, and edge filling to obtain the cover plate 300 .

[0159] For detailed description of the features that are the same between this embodiment and the above embodiment, please refer to the above embodiment, which will not be repeated here.

[0160] The optical coating 100 and the cover plate 300 of the present application are further described below through specific embodiments.

[0161] Example 1

[0162] The cover plate 300 of this embodiment is prepared by the following steps:

[0163] (1) providing a PET substrate (substrate layer 210) having a texture layer 220, placing it in a sputtering coating device, and evacuating the device to a pressure lower than 0.003 Pa;

[0164] (2) Before coating, the PET substrate with the texture layer 220 and the carrier are baked at a temperature of 70° C. for 30 minutes to remove moisture from the PET substrate with the texture layer 220 and the carrier;

[0165] (3) Using low-energy plasma to clean the surface of the texture layer 220 to improve the surface activity, the cleaning time is 3 minutes;

[0166] (4) providing a Si-Nb-Zn target (target of the low-folding layer 10) and a Nb-Zn target (target of the high-folding layer 20), wherein the Si-Nb-Zn target comprises 80% Si, 10% Nb and 10% Zn by mass; and the Nb-Zn target comprises 85% Nb and 15% Zn by mass;

[0167] (5) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 118 nm as the first high-fold layer 20;

[0168] (6) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 40 nm as the first low-fold layer 10;

[0169] (7) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 8 nm as the second high-fold layer 20;

[0170] (8) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 28 nm as the second low-fold layer 10;

[0171] (9) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 15 nm as the third high-fold layer 20;

[0172] (10) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 22 nm as the third low-fold layer 10;

[0173] (11) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 81 nm as the fourth high-fold layer 20;

[0174] (12) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 167 nm as the fourth low-fold layer 10;

[0175] (13) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 50 nm as the fifth high-fold layer 20;

[0176] (14) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 88 nm as the fifth low-fold layer 10;

[0177] (15) Using Nb-Zn target material for deposition and oxidation to form Nb-Zn-O, the deposition thickness is 53 nm, as the sixth high-folding layer 20. After the coating is completed, the coating equipment is broken to remove the film product;

[0178] (16) forming a cover bottom layer 230 on the surface of the sixth high fold layer 20 to obtain a decorative film 200; and

[0179] (17) A glass plate (cover body 310 ) is provided, and the decorative film 200 is bonded to the surface of the glass plate to obtain the cover plate 300 .

[0180] The structural diagram of the cover plate 300 of this embodiment is as follows Fig.10 shown.

[0181] Example 2

[0182] The cover plate 300 of this embodiment is prepared by the following steps:

[0183] (1) providing a PET substrate (substrate layer 210) having a texture layer 220, placing it in a sputtering coating device, and evacuating the device to a pressure lower than 0.003 Pa;

[0184] (2) Before coating, the PET substrate with the texture layer 220 and the carrier are baked at a temperature of 70° C. for 30 minutes to remove moisture from the PET substrate with the texture layer 220 and the carrier;

[0185] (3) Using low-energy plasma to clean the surface of the texture layer 220 to improve the surface activity, the cleaning time is 3 minutes;

[0186] (4) providing a Si-Nb-Y target (target of the low-folding layer 10) and a Nb-Y target (target of the high-folding layer 20), wherein the Si-Nb-Y target comprises 80% Si, 10% Nb and 10% Y by mass; and the Nb-Y target comprises 85% Nb and 15% Y by mass;

[0187] (5) using a Nb-Y target material to deposit and oxidize to form Nb-YO with a deposition thickness of 118 nm as the first high-fold layer 20;

[0188] (6) using a Si-Nb-Y target material to deposit and oxidize to form Si-Nb-YO with a deposition thickness of 40 nm as the first low-fold layer 10;

[0189] (7) using a Nb-Y target material to deposit and oxidize to form Nb-YO with a deposition thickness of 8 nm as the second high-fold layer 20;

[0190] (8) using a Si-Nb-Y target material to deposit and oxidize to form Si-Nb-YO with a deposition thickness of 28 nm as the second low-fold layer 10;

[0191] (9) using a Nb-Y target material to deposit and oxidize to form Nb-YO with a deposition thickness of 15 nm as the third high-fold layer 20;

[0192] (10) using a Si-Nb-Y target material to deposit and oxidize to form Si-Nb-YO with a deposition thickness of 22 nm as the third low-fold layer 10;

[0193] (11) using a Nb-Y target material to deposit and oxidize to form Nb-YO with a deposition thickness of 81 nm as the fourth high-fold layer 20;

[0194] (12) using a Si-Nb-Y target material to deposit and oxidize to form Si-Nb-YO with a deposition thickness of 167 nm as the fourth low-fold layer 10;

[0195] (13) using a Nb-Y target material to deposit and oxidize to form Nb-YO with a deposition thickness of 50 nm as the fifth high-fold layer 20;

[0196] (14) using a Si-Nb-Y target material to deposit and oxidize to form Si-Nb-YO with a deposition thickness of 88 nm as the fifth low-fold layer 10;

[0197] (15) Using Nb-Y target material to deposit and oxidize to form Nb-YO, the deposition thickness is 53nm, as the sixth high-folding layer 20. After the coating is completed, the coating equipment is broken to remove the film product;

[0198] (16) forming a cover bottom layer 230 on the surface of the sixth high fold layer 20 to obtain a decorative film 200; and

[0199] (17) A glass plate (cover body 310 ) is provided, and the decorative film 200 is bonded to the surface of the glass plate to obtain the cover plate 300 .

[0200] The structural diagram of the cover plate 300 of this embodiment is as follows Fig.10 shown.

[0201] Example 3

[0202] The cover plate 300 of this embodiment is prepared by the following steps:

[0203] (1) providing a PET substrate (substrate layer 210) having a texture layer 220, placing it in a sputtering coating device, and evacuating the device to a pressure lower than 0.003 Pa;

[0204] (2) Before coating, the PET substrate with the texture layer 220 and the carrier are baked at a temperature of 70° C. for 30 minutes to remove moisture from the PET substrate with the texture layer 220 and the carrier;

[0205] (3) Using low-energy plasma to clean the surface of the texture layer 220 to improve the surface activity, the cleaning time is 3 minutes;

[0206] (4) providing a Si-Nb-Zn target (a target for the low-folding layer 10 and a target for the buffer layer 30) and a Nb-Zn target (a target for the high-folding layer 20), wherein the Si-Nb-Zn target comprises 80% Si, 10% Nb and 10% Zn by mass; and the Nb-Zn target comprises 85% Nb and 15% Zn by mass;

[0207] (5) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 117 nm as the first high-fold layer 20;

[0208] (6) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the first buffer layer 30;

[0209] (7) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 40 nm as the first low-fold layer 10;

[0210] (8) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the second buffer layer 30;

[0211] (9) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 6 nm as the second high-folding layer 20;

[0212] (10) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the third buffer layer 30;

[0213] (11) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 28 nm as the second low-fold layer 10;

[0214] (12) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the fourth buffer layer 30;

[0215] (13) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 13 nm as the third high-fold layer 20;

[0216] (14) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the fifth buffer layer 30;

[0217] (15) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 22 nm as the third low-fold layer 10;

[0218] (16) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the sixth buffer layer 30;

[0219] (17) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 79 nm as the fourth high-fold layer 20;

[0220] (18) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the seventh buffer layer 30;

[0221] (19) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 167 nm as the fourth low-fold layer 10;

[0222] (20) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the eighth buffer layer 30;

[0223] (21) using a Nb-Zn target material to deposit and oxidize to form Nb-Zn-O with a deposition thickness of 48 nm as the fifth high-fold layer 20;

[0224] (22) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the ninth buffer layer 30;

[0225] (23) using a Si-Nb-Zn target material to deposit and oxidize to form Si-Nb-Zn-O with a deposition thickness of 88 nm as the fifth low-fold layer 10;

[0226] (24) using a Si-Nb-Zn target to deposit Si-Nb-Zn with a thickness of 1 nm as the tenth buffer layer 30;

[0227] (25) Using Nb-Zn target material for deposition and oxidation to form Nb-Zn-O, the deposition thickness is 52 nm, as the sixth high-folding layer 20. After the coating is completed, the coating equipment is broken to remove the film product;

[0228] (26) forming a cover bottom layer 230 on the surface of the sixth high fold layer 20 to obtain a decorative film 200; and

[0229] (27) A glass plate (cover body 310 ) is provided, and the decorative film 200 is bonded to the surface of the glass plate to obtain the cover plate 300 .

[0230] It should be noted that, since the refractive index of the buffer layer 30 is close to that of the high refractive index layer 20 , compared with Example 1, after inserting a 1 nm thick buffer layer 30 , the deposition thickness of the high refractive index layer adjacent to the buffer layer 30 is reduced by 1 nm as a compensation correction.

[0231] The structural diagram of the cover plate 300 of this embodiment is as follows Fig.11 shown.

[0232] Comparative Example 1

[0233] In this comparative example, the glass plate of Example 1 is used as the cover plate 300 .

[0234] Comparative Example 2

[0235] The cover plate 300 of this comparative example is prepared by the following steps:

[0236] (1) providing a PET substrate (substrate layer 210) having a texture layer 220, placing it in a sputtering coating device, and evacuating the device to a pressure lower than 0.003 Pa;

[0237] (2) Before coating, the PET substrate with the texture layer 220 and the carrier are baked at a temperature of 70° C. for 30 minutes to remove moisture from the PET substrate with the texture layer 220 and the carrier;

[0238] (3) Using low-energy plasma to clean the surface of the texture layer 220 to improve the surface activity, the cleaning time is 3 minutes;

[0239] (4) Providing Si target (target of low fold layer 10) and Nb target (target of high fold layer 20);

[0240] (5) using a Nb target material to deposit and oxidize to form Nb2O5 with a deposition thickness of 118 nm as the first high-fold layer 20;

[0241] (6) using a Si-target material to deposit and oxidize to form SiO2 with a deposition thickness of 40 nm as the first low-fold layer 10;

[0242] (7) using a Nb target material to deposit and oxidize to form Nb2O5 with a deposition thickness of 8 nm as the second high-fold layer 20;

[0243] (8) using a Si target to deposit and oxidize SiO2 to a thickness of 28 nm as the second low-fold layer 10;

[0244] (9) using a Nb target material to deposit and oxidize to form Nb2O5 with a deposition thickness of 15 nm as the third high-fold layer 20;

[0245] (10) using a Si target to deposit and oxidize to form SiO2 with a deposition thickness of 22 nm as the third low-fold layer 10;

[0246] (11) using a Nb target material to deposit and oxidize to form Nb2O5 with a deposition thickness of 81 nm as the fourth high-fold layer 20;

[0247] (12) using a Si target to deposit and oxidize SiO2 with a deposition thickness of 167 nm as the fourth low-fold layer 10;

[0248] (13) using a Nb target material to deposit and oxidize to form Nb2O5 with a deposition thickness of 50 nm as the fifth high-fold layer 20;

[0249] (14) using a Si target to deposit and oxidize to form SiO2 with a deposition thickness of 88 nm as the fifth low-fold layer 10;

[0250] (15) Using Nb target material to deposit and oxidize to form Nb2O5, the deposition thickness is 53nm, as the sixth high-folding layer 20. After the coating is completed, the coating equipment is broken to remove the film product;

[0251] (16) forming a cover bottom layer 230 on the surface of the sixth high fold layer 20 to obtain a decorative film 200; and

[0252] (17) A glass plate (cover body 310 ) is provided, and the decorative film 200 is bonded to the surface of the glass plate to obtain the cover plate 300 .

[0253] Various performance tests were performed on the cover plate 300 of each embodiment and comparative example.

[0254] (1) Average reflectivity: The average reflectivity of the cover plate 300 was measured using an ultraviolet spectrophotometer with light having a wavelength of 550 nm and an incident angle of 10°.

[0255] (2) Brightness test: measured using a Konica Minolta CM-700D colorimeter.

[0256] Table 1 Reflectivity and brightness of the cover plate 300 of Examples 1 to 3 and Comparative Example 1

[0257] Example Average reflectivity (%) brightness Example 1 60％ 80 Example 2 60％ 80 Example 3 60％ 80 Comparative Example 1 8％ 34

[0258] From the test results of Examples 1 to 3 and Comparative Example 1, it can be seen that, compared with ordinary glass plates, the cover plate 300 of the present embodiment has higher visible light reflectivity and brightness, and has a ceramic texture. In addition, the cover plate 300 prepared in Examples 1 to 3 of the present application is nearly colorless when viewed from different incident angles.

[0259] (3) Stress test method: A quartz glass sheet with a diameter of 30 mm and a thickness of 0.5 mm was used to directly coat the optical coating 100 on the surface of the quartz glass sheet in a furnace according to the preparation steps of the respective embodiments and comparative examples. The overall stress value of the optical coating 100 of each embodiment and comparative example was calculated based on the profile change of the quartz glass sheet before and after coating.

[0260] Table 2 Compressive stress of the optical coating 100 of Examples 1 to 3 and Comparative Example 2

[0261] Example Compressive stress of sample 1 Compressive stress of sample 2 Compressive stress of sample 3 Average compressive stress Example 1 112MPa 94MPa 106MPa 104MPa Example 2 101MPa 107MPa 99MPa 102.3MPa Example 3 87MPa 81MPa 65MPa 77.7MPa Comparative Example 2 158MPa 175MPa 167MPa 166.7MPa

[0262] It can be seen from the test results of Examples 1 to 3 and Comparative Example 2 that, compared with the solution of Comparative Example 2, the optical coating 100 (Examples 1 and 2) prepared from the materials of the high fold layer 20 and the low fold layer 10 of the embodiment of the present application has lower compressive stress when the thickness of the optical coating 100 is equal. In addition, it can be seen from the test results of Examples 1 to 3 that, compared with the optical coating 100 of Examples 1 and 2, after the buffer layer 30 is added between the high fold layer 20 and the low fold layer 10, the compressive stress of the optical coating 100 with the buffer layer 30 in Example 3 is smaller when the thickness is equal.

[0263] (4) Bending resistance test: After the cover plate 300 of each embodiment and comparative example is made into a 3D glass cover plate 300 product, it is stored under constant temperature and humidity conditions (temperature 65±1°C, humidity 91% to 95% RH) for 14 days. After being taken out, the 3D arc edge position is observed for coating shedding and microcracks.

[0264] Fig.12 This is a picture of the cover plate 300 of Example 1 of the present application after undergoing a bending resistance test. Fig.13 This is a picture of the cover plate 300 of Example 2 of the present application after undergoing a bending resistance test. Fig.14 This is a picture of the cover plate 300 of Example 3 of the present application after undergoing a bending resistance test. Fig.15 This is a picture of the cover plate 300 of comparative example 2 of the present application after the bending resistance test.

[0265] Depend on Figures 12 to 15 The bending resistance test of Examples 1 to 3 and Comparative Example 2 shows that the optical coating 100 of the cover plate 300 of Examples 1 to 3 and Comparative Example 2 has no falling off phenomenon. The optical coating 100 of the cover plate 300 of Examples 1 to 3 has no microcracks, while the optical coating 100 of the cover plate 300 of Comparative Example 2 has microcracks.

[0266] Fig.16 It is a structural diagram of an electronic device 500 according to an embodiment of the present application. Fig.17 It is a schematic diagram of a partial exploded structure of an electronic device 500 according to an embodiment of the present application. Fig.18 It is a circuit block diagram of an electronic device 500 according to an embodiment of the present application.

[0267] See also Figures 16 to 18The embodiment of the present application further provides an electronic device 500, which includes a display screen 510, a cover plate 300 described in the embodiment of the present application, and a processor 530. The cover plate 300 is disposed opposite to the display screen 510; the processor 530 is located between the cover plate 300 and the display screen 510, and the processor 530 is electrically connected to the display screen 510 for controlling the display screen 510 to display.

[0268] It should be noted that the cover body 310 is closer to the outer surface of the electronic device 500 than the cover bottom layer 230. It can be understood that the cover bottom layer 230 faces the inside of the electronic device 500, and the cover body 310 faces the outside of the electronic device 500. The cover bottom layer 230 is farther away from the user contact surface, and the cover body 310 is closer to the user contact surface.

[0269] The electronic device 500 of the embodiment of the present application may be, but is not limited to, a portable electronic device 500 such as a mobile phone, a tablet computer, a laptop computer, a desktop computer, a smart bracelet, a smart watch, an e-reader, a game console, etc.

[0270] For a detailed description of the cover plate 300, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here. The cover plate 300 of the present application can be, but is not limited to, at least one of the rear cover plate 300 of an electronic device, a decorative piece, etc. In the embodiment of the present application, the cover plate 300 of the electronic device is illustrated and described by taking the rear cover plate of the electronic device 500, that is, the battery rear cover, as an example, which should not be understood as a limitation on the optical coating 100 and the cover plate 300 of the embodiment of the present application.

[0271] Optionally, the display screen 510 may be, but is not limited to, one or more of a liquid crystal display screen, a light emitting diode display screen (LED display screen), a micro light emitting diode display screen (Micro LED display screen), a sub-millimeter light emitting diode display screen (Mini LED display screen), an organic light emitting diode display screen (OLED display screen), etc.

[0272] Optionally, the processor 530 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), a microprocessor, a microcontroller, a main processor, a controller, and an ASIC, etc. The processor 530 is used to execute various types of digital storage instructions, such as software or firmware programs stored in a memory, which enables the computing device to provide a wide variety of services.

[0273] Optionally, the electronic device 500 of the present application further includes a memory 550. The memory 550 is electrically connected to the processor 530 and is used to store program codes required for the processor 530 to run, program codes required for controlling the display screen 510, display content of the display screen 510, and the like.

[0274] Optionally, the memory 550 may include a volatile memory (Volatile Memory), such as a random access memory (Random Access Memory, RAM); the memory 550 may also include a non-volatile memory (NVM), such as a read-only memory (Read-Only Memory, ROM), a flash memory (Flash Memory, FM), a hard disk drive (Hard Disk Drive, HDD) or a solid-state drive (SSD). The memory 550 may also include a combination of the above-mentioned types of memory.

[0275] In some embodiments, the electronic device 500 of the embodiment of the present application further includes a middle frame 520 and a camera module 570, wherein the middle frame 520 is disposed between the display screen 510 and the cover plate 300, and the side of the middle frame 520 is exposed to the cover plate 300 and the display screen 510. The middle frame 520 and the cover plate 300 enclose a housing space (not shown), and the housing space is used to accommodate the processor 530, the memory 550 and the camera module 570. The camera module 570 is electrically connected to the processor 530, and is used to shoot under the control of the processor 530.

[0276] Optionally, the cover plate 300 has a light-transmitting portion 301, and the camera module 570 can shoot through the light-transmitting portion 301 on the cover plate 300, that is, the camera module 570 in this embodiment is a rear camera module 570. It can be understood that in other embodiments, the light-transmitting portion 301 can be set on the display screen 510, that is, the camera module 570 is a front camera module 570. In the schematic diagram of this embodiment, the light-transmitting portion 301 is illustrated as an opening. In other embodiments, the light-transmitting portion 301 may not be an opening, but a light-transmitting material, such as plastic, glass, etc.

[0277] It can be understood that the electronic device 500 described in this embodiment is merely a form of the electronic device 500 used by the cover 300, and should not be understood as a limitation on the electronic device 500 provided in this application, nor should it be understood as a limitation on the cover 300 provided in each embodiment of this application.

[0278] Mentioning "embodiment" and "implementation method" in this application means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrases in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments. In addition, it should also be understood that the features, structures or characteristics described in the various embodiments of the present application can be arbitrarily combined to form another embodiment that does not deviate from the spirit and scope of the technical solution of the present application, if there is no contradiction between them.

[0279] Finally, it should be noted that the above implementation modes are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application has been described in detail with reference to the above preferred implementation modes, a person of ordinary skill in the art should understand that the technical solution of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present application.

Claims

1. An optical coating, characterized in that: include: A low-fold layer, the low-fold layer comprising a Si-Me1-O composite material, wherein the Poisson's ratio of the oxide of Me1 is greater than the Poisson's ratio of silicon dioxide; as well as A high fold layer is stacked with the low fold layer, and the refractive index of the high fold layer is greater than the refractive index of the low fold layer.

2. The optical coating according to claim 1, characterized in that: The range of the Poisson's ratio v1 of the oxide of Me1 is: v1≥0.

2.

3. The optical coating according to claim 1, characterized in that: In the Si-Me1-O composite materials, the mass fraction of Me1 element ranges from 5% to 40%.

4. The optical coating according to claim 3, characterized in that: The mass fraction of Si element in Si-Me1-O composite materials ranges from 19% to 42%.

5. The optical coating according to any one of claims 1 to 4, characterized in that: Me1 is a first metal element, and the first metal element includes at least one of niobium, aluminum, titanium, zirconium, zinc, cerium, chromium, gallium, tin, indium, tantalum, and yttrium.

6. The optical coating according to claim 1, characterized in that: The high-fold layer includes an R-Me2-O composite material, wherein the R element includes at least one of niobium, titanium, and tantalum, and the R element is different from the Me2 element; the Poisson's ratio of the Me2 oxide is greater than the Poisson's ratio of the R oxide.

7. The optical coating according to claim 6, characterized in that: The range of the Poisson's ratio v2 of the oxide of Me2 is: v2≥0.

25.

8. The optical coating according to claim 6, characterized in that: In the R-Me2-O composites, the mass fraction of Me2 element ranges from 2% to 25%.

9. The optical coating according to claim 8, characterized in that: In the R-Me2-O composites, the mass fraction of the R element ranges from 48% to 70%.

10. The optical coating according to any one of claims 6 to 9, characterized in that: Me2 is a second metal element, and the second metal element includes at least one of zirconium, zinc, cerium, chromium, gallium, tin, indium, tantalum, and yttrium.

11. The optical coating according to any one of claims 1-4, 6-9, characterized in that: The optical coating also includes a buffer layer, which is located between the high fold layer and the low fold layer. The buffer layer includes Si element or Si-Me3 composite material, and the Poisson's ratio of the Me3 element is greater than the Poisson's ratio of the Si element.

12. The optical coating according to claim 11, characterized in that: The range of the Poisson's ratio v3 of the Si-Me3 composite material is: 0.25≤v3≤0.

4.

13. The optical coating according to claim 11, characterized in that: The mass fraction of the Me3 element in the buffer layer ranges from 0% to 50%, and the mass fraction of the Si element ranges from 50% to 100%.

14. The optical coating according to claim 11, characterized in that: The thickness of the buffer layer is less than or equal to 2 nm.

15. The optical coating according to claim 11, characterized in that: Me3 is a third metal element, and the third metal element includes at least one of niobium, zirconium, zinc, gallium, tin, indium, tantalum, yttrium, aluminum, titanium, and chromium.

16. A decorative film, characterized in that: The decorative film comprises: a substrate layer; and The optical coating according to any one of claims 1 to 15, wherein the optical coating is disposed on one side of the substrate layer.

17. A cover plate, characterized in that: The cover plate comprises: Cover body; an adhesive layer disposed on a surface of the cover body; and The decorative film as described in claim 16 is arranged on the surface of the adhesive layer facing away from the cover body, and the substrate layer is located between the cover body and the optical coating.

18. An electronic device, characterized in that: include: Display screen; The cover plate of claim 17, wherein the cover plate is disposed opposite to the display screen; as well as A processor is located between the cover plate and the display screen, and the processor is electrically connected to the display screen to control the display screen to display.

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