Color conversion substrate and manufacturing method thereof, and color conversion display device

Abstract

The present invention discloses a color conversion substrate and a manufacturing method thereof, and a color conversion display device. The color conversion substrate comprises a base substrate, a composite coating including a black matrix layer and a reflective coating, a groove array provided on the base substrate surface where the composite coating is located and penetrating the composite coating, and a color conversion film layer filled in the groove array and attached to the base substrate surface. The color conversion substrate has the advantages of high wall thickness, high reflectivity, high light extraction efficiency, and low process and equipment costs.

Description

Technical Field

[0001] The invention belongs to the field of display devices, and in particular relates to a color conversion substrate and a manufacturing method thereof, and also relates to a color conversion display device comprising the color conversion substrate. Background Art

[0002] LED display has the advantages of high brightness, high energy efficiency, high color gamut, and high contrast. Mini-LED and Micro-LED will be the focus of the next generation of display technology. They are both based on tiny LED crystal particles as pixel light-emitting points. The difference is that Micro-LED uses 1-10μm LED chips to achieve display screens with pixel particles of 0.05mm or smaller, while Mini-LED uses LED chips of tens of microns to achieve display screens with pixel particles of 0.5-1.2mm.

[0003] However, there are many difficulties in the mass production of Mini-LED and Micro-LED, such as the well-known high cost of red light chips and the difficulty of mass transfer. Therefore, the current research is more about the technical solution of blue light LED combined with quantum dot color conversion layer to achieve the three primary colors. Among them, the groove solution is generally achieved by using black photoresist material in combination with photolithography. Due to the limitations of photolithography, the film thickness is generally less than 10μm. Under this film thickness, the conversion efficiency of the quantum dot color conversion layer is generally insufficient, and blue light will still leak out, resulting in a reduction in the display color gamut. Therefore, the current Micro-LED color conversion technology on the market requires a traditional color filter layer.

[0004] Several color conversion film solutions are provided in the known technology, but none of them clearly describes the pixelation solution of the patterned substrate and the quantum dot color conversion layer. Furthermore, in Mini / Micro LED direct display devices using quantum dots as light conversion materials, in order to improve the blue light absorption rate of the quantum dot conversion layer (>99%), when a color filter is not used, the thickness of the quantum dot film layer needs to be thicker (>30μm), so the height of the retaining wall needs to be >30μm to ensure that there is no overflow when filling the quantum dot light conversion layer. The commonly used method for preparing retaining walls is photolithography, but when the thickness of the retaining wall exceeds 10μm, the ability to refine the retaining wall will be limited due to insufficient exposure. At this time, the photolithography method for making retaining walls will no longer be applicable. In addition, the retaining wall needs to have high absorbance or reflectivity to avoid light crosstalk between pixels. At present, light-absorbing substances are added when photolithography is used to prepare retaining walls to prevent light crosstalk between pixels. The addition of light-absorbing substances will absorb a large amount of light emitted by the device, reducing the light output efficiency and resulting in an increase in the final energy consumption. Summary of the invention

[0005] In view of this, the present invention is necessary to provide a color conversion substrate and a manufacturing method thereof, wherein a black matrix layer and a reflective coating with reflective properties are sequentially coated on a base substrate, and then a groove array substrate with a target pixel size and shape is obtained by laser etching, and finally a hole is filled by printing or other methods to form a quantum dot color conversion film layer. The color conversion substrate has the advantages of high barrier film thickness, high light extraction efficiency, and low manufacturing cost.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention first provides a color conversion substrate, which includes:

[0008] substrate substrate;

[0009] A composite coating, comprising a black matrix layer and a reflective coating layer, wherein the black matrix layer and the reflective coating layer are sequentially disposed on the surface of the base substrate;

[0010] A groove array is provided on the surface of the substrate where the composite coating is located and penetrates the composite coating;

[0011] A color conversion film layer is filled in the groove array and adhered to the surface of the base substrate.

[0012] Furthermore, the base substrate is selected from a glass substrate with a size of 10×10 cm to 30×30 cm and a thickness of 0.2 mm to 1.0 mm.

[0013] Furthermore, the thickness of the black matrix layer is controlled to be 0.2-20 μm, and the optical density OD is controlled to be 4.0-4.5;

[0014] The thickness of the reflective coating is 20-150 μm;

[0015] The thickness of the groove array is greater than 20 μm;

[0016] The thickness of the color conversion film layer is 0.2-100 μm.

[0017] Furthermore, the color conversion film layer includes a first quantum dot light-emitting unit and a second quantum dot light-emitting unit, and the first quantum dot light-emitting unit and the second quantum dot light-emitting unit are independently selected from green light quantum dots or red light quantum dots.

[0018] The present invention further provides a method for manufacturing a color conversion substrate as described in any one of the above, comprising the following steps:

[0019] Providing a substrate;

[0020] Forming a composite coating: coating a black matrix material on one side of the substrate to form a black matrix layer, and coating a reflective coating slurry on the surface of the black matrix layer to form a reflective coating;

[0021] Etching the composite coating to form a groove array on the substrate;

[0022] The quantum dot glue is filled in the groove array, and after the glue solvent evaporates, a color conversion film layer is formed.

[0023] Further, the reflective coating slurry is composed of: 1-30%wt reflective component, 4-60%wt polyacrylate, 0.1-3%wt curing agent and the balance of n-butyl ether solvent, the reflective coating slurry has a solid content of 2-80% and a viscosity of 5000-10000 cP, wherein the reflective component is selected from at least one of aluminum powder, silver powder, titanium dioxide and glass beads;

[0024] The preparation steps of the reflective coating slurry are specifically as follows: adding the reflective component to the n-butyl ether solution of polyacrylate according to the proportion, stirring evenly, mixing in the curing agent, stirring evenly again, and preparing the reflective coating slurry.

[0025] Furthermore, the reflective component is aluminum powder, and the particle size of the aluminum powder is less than 6 μm;

[0026] The polyacrylate has hydroxyl groups at both ends of the molecular chain or on the side chain, and the molecular weight is 3000-5000;

[0027] The curing agent is selected from at least one of toluene diisocyanate, hexamethylene diisocyanate and diphenylmethane diisocyanate.

[0028] Furthermore, the reflective coating slurry is coated on the surface of the black matrix layer to form the reflective coating. The specific steps are: coating the reflective coating slurry on the surface of the black matrix layer, controlling the wet film thickness to 30-150 μm, and baking at 160-180° C. for 20-30 min to form the reflective coating.

[0029] Furthermore, the specific steps of etching the composite coating are: etching the composite coating using ultraviolet laser technology, wherein the laser wavelength is 193 to 365 nm, the power is 3 to 20 W, the pulse repetition frequency is 30 to 120 KHz, the laser spot size is selected from 5 to 40 μm, and the size of the etched hole is 20 to 1000 μm.

[0030] The present invention also provides a color conversion display device, which is composed of a color conversion substrate as described in any of the above items bonded to a blue light LED substrate, wherein the blue light LED substrate includes a substrate, a blue light LED chip is bonded to one side of the substrate, a frame sealing glue is provided on the surface of the substrate to which the blue light LED chip is bonded, the blue light LED chip is aligned with the color conversion film layer, and the frame sealing glue is bonded to the reflective coating.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The groove array of the color conversion substrate in the present invention is deep, which can realize a high-thickness retaining wall. The color conversion film layer has a high thickness. A reflective coating is used as the retaining wall material of the color conversion film layer. Due to its good shielding performance for visible light, the problem of light crosstalk between adjacent pixels is effectively solved; in addition, due to the reflection effect of the reflective coating surface on light, the absorption of blue light sources by traditional retaining wall materials is effectively avoided, thereby improving the light output efficiency. In the color conversion substrate, the blue light absorption rate of the color conversion film layer is greater than 99%. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic structural diagram of a color conversion substrate in a preferred embodiment of the present invention;

[0034] Figure 2 for Figure 1 Schematic diagram of the manufacturing process of the medium color conversion substrate;

[0035] Figure 3 FIG. 1 is a schematic diagram of the structure of a color conversion display device in a preferred embodiment of the present invention.

[0036] In the figure: a base substrate 10, a black matrix layer 101, a reflective coating 102, a groove array 103, a color conversion film layer 104, a green light quantum dot solution 1041, a red light quantum dot solution 1042, and a diffusion particle solution 1043;

[0037] Substrate 20, blue LED chip 201, frame sealant 202;

[0038] Quantum dot glue filling device 30. DETAILED DESCRIPTION

[0039] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0041] The first aspect of the present invention discloses a color conversion substrate, which comprises:

[0042] substrate substrate;

[0043] A composite coating, comprising a black matrix layer and a reflective coating layer, wherein the black matrix layer and the reflective coating layer are sequentially disposed on the surface of the base substrate;

[0044] A groove array is provided on the surface of the substrate where the composite coating is located and penetrates the composite coating;

[0045] A color conversion film layer is filled in the groove array and adhered to the surface of the base substrate.

[0046] The color conversion substrate uses a reflective coating as a retaining wall material, and uses a reflective coating and a black matrix layer as a pixelated retaining wall solution. The reflective coating has a high reflectivity to prevent light crosstalk between pixels, and the light in the pixel can still be emitted from the front after being reflected multiple times on the side, without causing a reduction in the amount of light emitted, thereby effectively improving the light efficiency. Its blue light absorption rate can reach more than 99%, and the blue light can be basically absorbed and converted.

[0047] Furthermore, the base substrate described in the present invention can be a conventional choice in the art. Preferably, in some specific embodiments of the present invention, the base substrate is selected from a glass substrate. Since the color conversion substrate in the present invention is mainly used for the preparation of Mini / Micro LED, the size is adjusted according to the size of Mini / Micro LED without special limitation. In some specific embodiments of the present invention, the base substrate has a size of 10×10cm to 30×30cm and a thickness of 0.2mm to 1.0mm.

[0048] Further, the black matrix layer refers to the black matrix material (BM) used in conventional liquid crystal color films. For example, in some embodiments of the present invention, the preparation process of the black matrix layer can be: the black matrix glue is applied to the surface of the white glass by spin coating or slit coating, more than 95% of the solvent is removed by vacuum, the pre-baking is 90°C / 1min, and finally the post-baking is 230°C / 20min to complete the preparation of the black matrix layer, and the dry film thickness is controlled at 0.2μm to 3μm. Among them, the black matrix glue can be prepared from 4 to 7wt% of acrylic resin, 5 to 7wt% of multifunctional monomer, 3 to 5wt% of carbon black, 1 to 3wt% of dispersant and the remainder of propylene glycol methyl ether acetate solvent, wherein the multifunctional monomer can be selected from glycerol 1,3-diglycerol alcohol diacrylate or bisphenol A propylene glycol dimethacrylate, and the dispersant can be selected from amino-β-cyclodextrin modified polymethacrylate, etc. It should be noted that the preparation of the above black matrix layer and the components of the black matrix glue are only used as examples to make the technical solution of the present invention clearer, and do not mean that only the above methods or compositions can be used. Conventional black matrix material preparation methods in the art are all acceptable. Further, in some specific embodiments of the present invention, the film thickness of the black matrix layer is controlled at 0.2 to 20 μm (dry film thickness), preferably at 0.2 to 3 μm, and the optical density OD is controlled at 4.0 to 4.5 (@450nm wavelength light). The function of the black matrix layer is mainly to avoid the reflection of ambient light by the reflective coating when the display device is working, thereby improving the contrast of the display device.

[0049] Furthermore, in order to increase the thickness of the color conversion film layer, thereby increasing the blue light absorption rate of the color conversion film layer (>99%), the thickness of the retaining wall material needs to be relatively high. Preferably, the height of the retaining wall material is >20 μm to ensure that the color conversion film layer does not overflow when being filled. Preferably, in some specific embodiments of the present invention, the thickness of the reflective coating is 20 to 150 μm, and more preferably, 40 to 70 μm.

[0050] The thickness of the groove array and the color conversion film layer can be designed according to the thickness of the retaining wall material. In some specific embodiments of the present invention, the thickness of the groove array is greater than 20 μm. It should be noted that the size of the groove array is designed according to the actual required pixel pattern size and is not particularly limited.

[0051] The thickness of the color conversion film layer is 0.2-100 μm, preferably 2-50 μm, and more preferably 30-40 μm.

[0052] Furthermore, the color conversion film layer includes a first quantum dot light-emitting unit and a second quantum dot light-emitting unit, the first quantum dot light-emitting unit and the second quantum dot light-emitting unit are independently selected from green light quantum dots or red light quantum dots, and the filling positions of the first quantum dot light-emitting unit and the second quantum dot light-emitting unit are adjusted according to the needs of designing the pixel pattern without any special limitation.

[0053] The second aspect of the present invention discloses a method for manufacturing the color conversion substrate as described in the first aspect of the present invention, comprising the following steps:

[0054] Providing a substrate;

[0055] Forming a composite coating: coating a black matrix material on one side of the substrate to form a black matrix layer, and coating a reflective coating slurry on the surface of the black matrix layer to form a reflective coating. The coating methods of the black matrix material and the reflective coating are not particularly limited. Conventional coating processes in the art can be used in the present invention. In some specific embodiments of the present invention, preferably, the black matrix material is coated by spin coating or slit coating, and the reflective coating is coated by spin coating, scraping or slit coating.

[0056] Etching the composite coating to form a groove array on the substrate;

[0057] The quantum dot glue is filled in the groove array, and after the glue solvent evaporates, a color conversion film layer is formed.

[0058] The color conversion film substrate is manufactured by this manufacturing method, because the traditional photolithography process (exposure, development, etc.) is avoided, thereby significantly reducing the process and equipment costs.

[0059] Furthermore, the composition of the reflective coating slurry in the present invention is: 1-30%wt reflective component, 4-60%wt polyacrylate, 0.1-3%wt curing agent and the balance of n-butyl ether solvent, the solid content of the reflective coating slurry is 2-80%, and the viscosity is 5000-10000 cP. The reflective component is selected from at least one of aluminum powder, silver powder, titanium dioxide, and glass microbeads. It is understood that the selection of reflective components is not limited to the above-mentioned ones, and conventional powders and particles with reflective properties in the field can be used in the scheme of the present invention;

[0060] The preparation steps of the reflective coating slurry are as follows: according to the ratio, add the reflective component to the n-butyl ether solution of polyacrylate, stir evenly, mix in the curing agent, stir evenly again, and prepare the reflective coating slurry. It should be noted that the reflective coating slurry needs to be stored at low temperature (2-8°C) and away from light.

[0061] Preferably, the reflective component is aluminum powder, and the particle size of the aluminum powder is less than 6 μm;

[0062] The polyacrylate has hydroxyl groups at both ends of the molecular chain or on the side chain, and the molecular weight is 3000-5000;

[0063] The curing agent can be selected from at least one of toluene diisocyanate, hexamethylene diisocyanate, and diphenylmethane diisocyanate. It can be understood that through the above preference, the properties of the reflective coating are better, but other types of polyacrylates and curing agents conventionally used in the art can be used in the present invention.

[0064] Furthermore, the reflective coating slurry is coated on the surface of the black matrix layer to form the reflective coating. The specific steps are as follows: coating the reflective coating slurry on the surface of the black matrix layer, controlling the wet film thickness to be 40 to 300 μm, pre-baking at 70 to 90°C for 2 to 4 minutes, and then baking at 160 to 180°C for 20 to 30 minutes to form the reflective coating, and controlling the dry film thickness to be 20 to 150 μm.

[0065] Furthermore, the composite coating is etched to form a groove array on the composite coating, and its specific etching range and size are not specifically limited. Etching is performed according to the patterning scheme required for processing. Preferably, etching using ultraviolet laser technology can reduce manufacturing costs. In some specific embodiments of the present invention, the specific steps of etching the composite coating are: etching on the composite coating using ultraviolet laser technology, wherein the wavelength of the ultraviolet laser is 193-365nm, the power is 3-20W, the pulse repetition frequency is 30-120KHz, the spot size of the laser is selected from 5-40μm, and the plane aperture size of the laser-etched groove is 20-1000μm. Preferably, the wavelength of the ultraviolet laser is selected from 355nm, the power is 15W, the pulse repetition frequency is 100KHz, and the spot size of the laser is 20μm.

[0066] Furthermore, the quantum dot glue liquid is prepared according to the design requirements of the pixelation scheme, and quantum dot materials of appropriate sizes are selected and dispersed in the adhesive in combination with diffusion particles to obtain green quantum dot glue liquid and red quantum dot glue liquid. It can be understood that the quantum dots described in the present invention are chromium selenide (CdSe) quantum dots, indium phosphide (InP) quantum dots or perovskite quantum dots conventionally used in the art, and their specific types are not particularly limited. The diffusion particles are conventionally used in the art and will not be elaborated here.

[0067] Furthermore, the quantum dot liquid is filled in the groove array. The methods that can be used include but are not limited to inkjet printing technology, dispensing technology, photolithography technology or screen printing technology. Any conventional method for filling quantum dot liquid in the art can be used. In some specific embodiments of the present invention, preferably, inkjet printing technology or dispensing technology is used.

[0068] The third aspect of the present invention discloses a color conversion display device, which is composed of a color conversion substrate as described in the first aspect of the present invention bonded to a blue light LED substrate, wherein the blue light LED substrate includes a substrate, and the substrate here mainly includes a blue light Mini LED substrate or a Micro LED substrate, a blue light LED chip is bonded to one side of the substrate, and a frame sealing glue is provided on the surface of the substrate to which the blue light LED chip is bonded, the blue light LED chip is aligned with the color conversion film layer, and the frame sealing glue is bonded to the reflective coating.

[0069] It is understandable that, since the blue LED chip is aligned with the color conversion film layer, the type of sealant, and the bonding process of the sealant and the reflective coating can all adopt known technologies in the art, so they are not elaborated here. The color conversion device can achieve full-color display function, avoiding the color conversion technology that appears on the market with the traditional LCD color film solution, and reducing the cost of materials and processes.

[0070] The technical solution of the present invention will be described more clearly and completely below in conjunction with the accompanying drawings and specific embodiments.

[0071] Figure 1 1 shows the structure of a color conversion substrate in a preferred embodiment of the present invention, which includes a base substrate 10, on which a black matrix layer 101 and a reflective coating layer 102 are sequentially formed, and the black matrix layer 101 and the reflective coating layer 102 constitute a composite coating on the surface of the base substrate 10; further, a groove array 103 is provided on the surface of the base substrate 10, and the groove array 103 penetrates the composite coating. Furthermore, a color conversion film layer 104 is also provided on the surface of the base substrate 10, and the color conversion film layer 104 is filled between the groove array 103.

[0072] Specifically, the material of the base substrate 10 is not particularly limited, and any conventional base substrate in the art can be used. In the present embodiment, the base substrate 10 is a glass substrate with a size of 10×10cm to 30×30cm and a thickness of 0.2mm to 1.0mm. Furthermore, the dry film thickness of the black matrix layer 101 is controlled at 0.2 to 3μm, the optical density OD is controlled at 4.0 to 4.5, the thickness of the reflective coating 102 is 20 to 150μm, the thickness of the groove array 103 is greater than 20μm, and the thickness of the color conversion film layer 104 is 2 to 50μm. For details, please continue to refer to Figure 1The color conversion film layer 104 is formed by filling the groove array with green light quantum dot solution 1041, red light quantum dot solution 1042 and diffusion particle solution 1043.

[0073] Figure 2 It is shown in Figure 1 The processing flow of the neutral color conversion substrate is specifically as follows: providing a base substrate 10; coating a black matrix material on one side of the base substrate 10 by spin coating or slit coating to form a black matrix layer 101; coating a reflective coating slurry on the surface of the black matrix layer 101 by spin coating, scraping or slit coating to form a reflective coating 102; etching the composite coating to form a groove array 103 on the base substrate 10;

[0074] The quantum dot glue liquid is injected into the groove array using a quantum dot glue liquid filling device 30 , and after the glue liquid solvent evaporates, a color conversion film layer 104 is formed. The quantum dot glue liquid filling device 30 is an inkjet head of an inkjet printing device.

[0075] Example 1

[0076] The method for making the color conversion substrate in this embodiment is as follows: Figure 2 :

[0077] Provide a glass substrate with a size of 100 mm*100 mm in length and width and a thickness of 0.5 mm;

[0078] A black matrix material is coated on one surface of a glass substrate by a spin coating method, with a film thickness controlled at 0.9 μm and an optical density (OD) controlled at 4.0;

[0079] Aluminum-silver paste was coated on the surface of the black matrix layer by a spin coating method, and the wet film thickness was controlled at 100 μm. The wet film sample was pre-baked at 90°C for 2 min and then post-baked at 160°C for 20 min to obtain an aluminum-silver paste layer with a thickness of 40 μm. The aluminum-silver paste was composed of aluminum powder with a particle size of less than 6 μm (10% wt), polyacrylate with a molecular weight of 3000 (60% wt), TDI (3% wt), and the remainder was n-butyl ether solvent. After stirring evenly, a coatable aluminum-silver paste was obtained, with a solid content of 30% and a viscosity of 5000 cP.

[0080] An ultraviolet laser marking machine is used to etch the composite coating on the surface of the substrate as needed to obtain a groove array, wherein the ultraviolet wavelength is preferably 355nm, the power is 3W, the pulse repetition frequency is 100KHz, and the laser spot size is selected to be 20μm.

[0081] The quantum dot glue liquid is injected into the groove array of the glass substrate using a dot glue device to obtain a color conversion film layer with a thickness of 2 to 50 μm.

[0082] Example 2

[0083] The method for making the color conversion substrate in this embodiment is as follows: Figure 2 :

[0084] Provide a glass substrate with a size of 100 mm*100 mm and a thickness of 0.5 mm;

[0085] A black matrix material is coated on one surface of a glass substrate using a slit coating method, with a film thickness controlled at 1.1 μm and an optical density (OD) controlled at 4.5;

[0086] Aluminum-silver paste was coated on the surface of the black matrix layer by a spin coating method, and the wet film thickness was controlled at 120 μm. The wet film sample was pre-baked at 70°C for 3 min and then post-baked at 170°C for 25 min to obtain an aluminum-silver paste layer with a thickness of 54 μm. The aluminum-silver paste was composed of aluminum powder (20% wt), polyacrylate with a molecular weight of 4000 (50% wt), HDI (2% wt), and the remainder was n-butyl ether solvent. After stirring evenly, a coatable aluminum-silver paste was obtained, with a solid content of 35% and a viscosity of 70,000 cP.

[0087] An ultraviolet laser marking machine is used to etch the composite coating on the surface of the substrate as needed to obtain a groove array, wherein the ultraviolet wavelength is preferably 355nm, the power is 10W, the pulse repetition frequency is 100KHz, and the laser spot size can be selected within a range of 30μm.

[0088] The quantum dot glue liquid is injected into the groove array of the glass substrate using a dot glue device to obtain a color conversion film layer with a thickness of 2 to 50 μm.

[0089] Example 3

[0090] The method for making the color conversion substrate in this embodiment is as follows: Figure 2 :

[0091] Provide a glass substrate with a size of 100 mm*100 mm and a thickness of 0.5 mm;

[0092] A black matrix material is coated on one surface of a glass substrate by a spin coating method, with a film thickness controlled at 1.0 μm and an optical density (OD) controlled at 4.2;

[0093] Aluminum-silver paste is coated on the surface of the black matrix layer by a scraping method, and the wet film thickness is controlled at 150 μm. The wet film sample is pre-baked at 70°C for 4 min and then post-baked at 180°C for 30 min to obtain an aluminum-silver paste layer with a thickness of 70 μm. The aluminum-silver paste is composed of aluminum powder (30% wt), polyacrylate with a molecular weight of 5000 (45% wt), MDI (3% wt), and the remainder is n-butyl ether solvent. After stirring evenly, a coatable aluminum-silver paste is obtained, with a solid content of 40% and a viscosity of 10000 cP.

[0094] An ultraviolet laser marking machine is used to etch the composite coating on the surface of the substrate as needed to obtain a groove array, wherein the ultraviolet wavelength is preferably 355nm, the power is 3W, the pulse repetition frequency is 100KHz, and the laser spot size can be selected in the range of 40μm.

[0095] The quantum dot glue liquid is injected into the groove array of the glass substrate by using an inkjet printing device to obtain a color conversion film layer with a thickness of 2 to 50 μm.

[0096] Example 4

[0097] The method for making the color conversion substrate in this embodiment is as follows: Figure 2 :

[0098] Provide a glass substrate with a size of 200 mm*200 mm and a thickness of 0.2 mm;

[0099] A black matrix material is coated on one surface of a glass substrate by a spin coating method, with a film thickness controlled at 0.2 μm and an optical density (OD) controlled at 4.0;

[0100] Titanium dioxide slurry is coated on the surface of the black matrix layer by a scraping method, and the wet film sample is pre-baked at 90°C for 2 minutes and then post-baked at 170°C for 25 minutes to obtain a titanium dioxide slurry layer with a thickness of 20 μm. The titanium dioxide slurry is composed of titanium dioxide powder (10% wt), polyacrylate with a molecular weight of 4000 (40% wt), MDI (0.1% wt), and the remainder is n-butyl ether solvent. After stirring evenly, a coatable titanium dioxide slurry is obtained, with a solid content of 30% and a viscosity of 5000 cP.

[0101] An ultraviolet laser marking machine is used to etch the composite coating on the surface of the substrate as needed to obtain a groove array, wherein the ultraviolet wavelength is preferably 193nm, the power is 3W, the pulse repetition frequency is 30KHz, and the laser spot size can be selected within a range of 20μm.

[0102] The quantum dot glue liquid is injected into the groove array of the glass substrate by using an inkjet printing device to obtain a color conversion film layer with a thickness of 0.2 to 100 μm.

[0103] Example 5

[0104] The method for making the color conversion substrate in this embodiment is as follows: Figure 2 :

[0105] Provide a glass substrate with a size of 300 mm*300 mm and a thickness of 1.0 mm;

[0106] A black matrix material is coated on one surface of a glass substrate by a spin coating method, with a film thickness controlled at 3 μm and an optical density (OD) controlled at 4.5;

[0107] Glass bead slurry was coated on the surface of the black matrix layer by a scraping method, and the wet film sample was pre-baked at 90°C for 2 min and post-baked at 160°C for 30 min to obtain a glass bead slurry layer with a thickness of 150 μm, wherein the glass bead slurry was composed of glass beads (20% wt), polyacrylate with a molecular weight of 3000 (60% wt), MDI (3% wt), and the remainder of n-butyl ether solvent. After stirring evenly, a coatable glass bead slurry was obtained, with a solid content of 35% and a viscosity of 8000 cP.

[0108] An ultraviolet laser marking machine is used to etch the composite coating on the surface of the substrate as needed to obtain a groove array, wherein the ultraviolet wavelength is preferably 365nm, the power is 20W, the pulse repetition frequency is 120KHz, and the laser spot size can be selected within a range of 20μm.

[0109] The quantum dot glue liquid is injected into the groove array of the glass substrate by using an inkjet printing device to obtain a color conversion film layer with a thickness of 0.2 to 100 μm.

[0110] Figure 3 A schematic diagram of the structure of a color conversion display device is shown. Figure 1 The color conversion substrate shown in the figure is bonded to a blue light LED substrate. Specifically, the blue light LED substrate includes a substrate 20, on one side of which a blue light LED chip 201 is bonded, and a sealing glue 202 is provided on the surface of the substrate 20 on which the blue light LED chip 201 is bonded. The sealing glue 202 is provided on the outer edge of the substrate 20, the blue light LED chip 201 is aligned with the color conversion film layer 104, and the sealing glue 202 is bonded to the reflective coating 102.

[0111] The color conversion device can realize full-color display function, avoiding the color conversion technology available on the market combined with traditional LCD color film solutions, and reducing the cost of materials and processes.

[0112] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0113] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for manufacturing a color conversion substrate, characterized in that: The following steps are involved: Providing a substrate; Forming a composite coating: coating a black matrix material on one side of the substrate to form a black matrix layer, and coating a reflective coating slurry on the surface of the black matrix layer to form a reflective coating; The composite coating is etched by ultraviolet laser technology to form a groove array on the substrate. The specific parameters of the ultraviolet laser are: the laser wavelength is 193-365nm, the power is 3-20W, the pulse repetition frequency is 30-120KHz, the laser spot size is selected from 5-40μm, and the size of the etched hole is 20-1000μm; Filling the groove array with quantum dot glue, and forming a color conversion film layer after the glue solvent evaporates; Wherein, the thickness of the reflective coating is 20-150 μm; the thickness of the groove array is greater than 20 μm.

2. The method for manufacturing a color conversion substrate according to claim 1, wherein: The substrate is a glass substrate with a size of 10×10 cm to 30×30 cm and a thickness of 0.2 mm to 1.0 mm.

3. The method for manufacturing a color conversion substrate according to claim 1, wherein: The thickness of the black matrix layer is controlled to be 0.2-20 μm, and the optical density OD is controlled to be 4.0-4.5; The thickness of the color conversion film layer is 0.2-100 μm.

4. The method for manufacturing a color conversion substrate according to claim 1, wherein: The color conversion film layer includes a first quantum dot light-emitting unit and a second quantum dot light-emitting unit, and the first quantum dot light-emitting unit and the second quantum dot light-emitting unit are independently selected from green light quantum dots or red light quantum dots.

5. The method for manufacturing a color conversion substrate according to claim 1, wherein: The reflective coating slurry is composed of: 1-30%wt reflective component, 4-60%wt polyacrylate, 0.1-3%wt curing agent and the balance of n-butyl ether solvent, the reflective coating slurry has a solid content of 2-80% and a viscosity of 5000-10000 cP, wherein the reflective component is selected from at least one of aluminum powder, silver powder, titanium dioxide and glass beads; The preparation steps of the reflective coating slurry are specifically as follows: adding the reflective component to the n-butyl ether solution of polyacrylate according to the proportion, stirring evenly, mixing in the curing agent, stirring evenly again, and preparing the reflective coating slurry.

6. The method for manufacturing a color conversion substrate according to claim 5, wherein: The reflective component is aluminum powder, and the particle size of the aluminum powder is less than 6 μm; The polyacrylate has hydroxyl groups at both ends of the molecular chain or on the side chain, and the molecular weight is 3000-5000; The curing agent is selected from at least one of toluene diisocyanate, hexamethylene diisocyanate and diphenylmethane diisocyanate.

7. The method for manufacturing a color conversion substrate according to claim 1, wherein: The specific steps of coating the reflective coating slurry on the surface of the black matrix layer to form the reflective coating are: coating the reflective coating slurry on the surface of the black matrix layer, controlling the wet film thickness to 40-300 μm, pre-baking at 70-90° C. for 2-4 minutes, and then baking at 160-180° C. for 20-30 minutes to form the reflective coating.

8. A color conversion display device, characterized in that: It is composed of a color conversion substrate obtained by the manufacturing method according to any one of claims 1 to 7 and bonded to a blue light LED substrate, wherein the blue light LED substrate comprises a substrate, a blue light LED chip is bonded to one side of the substrate, a frame sealing glue is provided on the surface of the substrate to which the blue light LED chip is bonded, the blue light LED chip is aligned with the color conversion film layer, and the frame sealing glue is bonded to the reflective coating.

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