A blue light cut-off filter film and its application

Abstract

The present application discloses a blue light cut-off filter film, comprising perovskite quantum dots and a matrix; the central wavelength of the blue light cut-off filter film is between 400 and 480 nm. The cut-off depth T of the cut-off filter film is less than 0.1%, and the peak transmittance is high. By adjusting the crystal form and size of the perovskite crystal quantum dots, the absorption center wavelength of the filter film can be adjusted within the range of 400nm-480nm. The cut-off filter film is used to filter out the harmful blue light part (<455nm) without reducing the intensity of healthy blue light, thereby achieving healthy and high color rendering display at the same time.

Description

Technical Field

[0001] The present application relates to a blue light cut-off filter film based on perovskite quantum dots, belonging to the field of materials. Background Art

[0002] Liquid crystal display technology (LCD) began to replace cathode ray tube technology in the 1990s and entered the display field. With the development of technology and the advancement of LCD panel manufacturing process technology, the application scenarios of LCD products have gradually developed from small-size screens to large-size screen displays. In the process of LCD technology development, the technical change of backlight source is an important milestone. In 2003, the European Union announced the implementation of the "Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS)" directive from 2006, and cold cathode lamp (CCFL) backlight technology began to withdraw from the market, replaced by light-emitting diode (LED) backlight display technology. LED has a high energy consumption ratio and good color expression. The current LED backlight is mainly obtained by blue light LED chips to excite yellow phosphors to obtain white backlight, so the proportion of blue light in LCD backlight is relatively high. Studies have shown that the high proportion of blue light in LEDs is easy to cause harm to the eyes, and this problem has attracted the attention of the country and consumers. First of all, harmful blue light has extremely high energy and can penetrate the lens directly to the retina, causing atrophy or even death of retinal pigment epithelial cells. The death of light-sensitive cells will lead to decreased or even complete loss of vision, and this damage is irreversible. Blue light can also cause macular degeneration. The lens in the human eye absorbs some blue light and gradually becomes cloudy to form cataracts, while most of the blue light will penetrate the lens. In particular, the lens of children is clearer and cannot effectively resist blue light, which makes it more likely to cause macular degeneration and cataracts. Secondly, due to the short wavelength of blue light, the focal point does not fall on the center of the retina, but a little closer to the retina. In order to see clearly, the eyeball will be in a state of tension for a long time, causing visual fatigue. Long-term visual fatigue may cause people to have symptoms such as deepening myopia, double vision, easy serialization when reading, and inability to concentrate, affecting people's learning and work efficiency. Third, blue light will inhibit the secretion of melatonin, which is an important hormone that affects sleep. The currently known role is to promote sleep and adjust jet lag. This can also explain why playing with mobile phones or tablets before going to bed will cause poor sleep quality and even difficulty falling asleep.

[0003] The harmful blue light band that we are exposed to in our daily life is 415nm-455nm. At present, people have developed many technologies to prevent blue light damage, and the use of anti-blue light protective film is one of them. Most blue light protective films use vacuum coating to coat multiple layers of films with different refractive indices or add high-concentration yellow blue light absorbers. The method of vacuum coating to coat multiple layers of films with different refractive indices will make the process too complicated and increase the manufacturing cost; the method of adding yellow blue light absorbers will cause color deviation, reduce the display quality of electronic products, and affect the user's experience of the product. Based on the above information, it is very necessary to develop a blue light protective film that is easy to prepare, accurately and efficiently filters blue light, and does not cause display color difference. Summary of the invention

[0004] According to one aspect of the present application, a blue light cut-off filter film is provided, wherein the cut-off depth T of the cut-off filter film is less than 0.1% and the peak transmittance is high. By adjusting the crystal form and size of the perovskite crystal quantum dots, the absorption center wavelength of the filter film can be adjusted within the range of 400nm-480nm. The cut-off filter film is used to filter out the harmful blue light part (<455nm) without reducing the intensity of healthy blue light, thereby achieving healthy and high color rendering display at the same time.

[0005] The blue light cut-off filter film is characterized in that it includes perovskite quantum dots and a matrix; the central wavelength of the blue light cut-off filter film is between 400 and 480 nm.

[0006] Optionally, the cutoff center wavelength of the blue light cutoff filter film is between 430 and 470 nm.

[0007] Optionally, the central cutoff wavelength of the blue light cutoff filter film is not greater than 455 nm, and the wavelength with a transmittance greater than 85% is not less than 470 nm.

[0008] Optionally, the cutoff depth T of the blue light cutoff filter film is less than 0.1%.

[0009] Optionally, the perovskite quantum dots are dispersed in the matrix.

[0010] Optionally, the size of the perovskite quantum dots in at least one dimension is 2 to 50 nm.

[0011] Optionally, the material of the matrix is ​​a polymer.

[0012] Optionally, the material of the matrix is ​​at least one selected from polyvinylidene fluoride, polyvinylidene fluoride and trifluoroethylene copolymer, polyacrylonitrile, polyvinyl acetate, cellulose acetate, cyanocellulose, polysulfone, aromatic polyamide, polyimide, polycarbonate, polystyrene, and polymethyl methacrylate.

[0013] Optionally, the perovskite quantum dots include at least one selected from quantum dots having a structural formula shown in Formula I;

[0014] A3Bi2X9 Formula I

[0015] Wherein, A is selected from (CH3NH2CH3 + )、CH3NH3 + At least one of; X is selected from Cl - Br - ,I - At least one of .

[0016] Optionally, the mass ratio of the matrix to the perovskite quantum dots is 1 to 100:1.

[0017] Optionally, the mass ratio of the matrix to the perovskite quantum dots is 1 to 30:1.

[0018] Optionally, the mass ratio of the matrix to the perovskite quantum dots is 3:1.

[0019] Optionally, the upper limit of the mass ratio of the matrix to the perovskite quantum dots is selected from 100:1, 80:1, 50:1, 30:1, 10:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1 or 2:1; the lower limit is selected from 80:1, 50:1, 30:1, 10:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1 or 1:1.

[0020] Optionally, the blue light cut-off filter film has a thickness of 0.001 to 5 mm.

[0021] Optionally, the blue light cut-off filter film further includes a barrier film;

[0022] The barrier film is stacked on the blue light cut-off filter film.

[0023] Optionally, at least one barrier film is laminated on the upper and lower surfaces of the blue light cut-off filter film.

[0024] Optionally, the material of the barrier film is selected from at least one of a polyvinylidene chloride film, an ethylene-vinyl alcohol copolymer film, a m-dimethylamine and adipic acid condensation polymer film, and an oxide coating film.

[0025] Optionally, the barrier film has a thickness of 15 um to 500 um.

[0026] According to another aspect of the present application, a method for preparing the blue light cut-off filter film is provided. The method is simple and easy to implement and suitable for large-scale production.

[0027] The method for preparing the blue light cut-off filter film is characterized by comprising the following steps:

[0028] The solution containing the perovskite quantum dot precursor and the matrix material is formed and dried to obtain the blue light cut-off filter film.

[0029] Optionally, the method for preparing the blue light cut-off filter film comprises the following steps:

[0030] (1) obtaining a precursor solution containing a matrix and a perovskite precursor;

[0031] (2) Molding the precursor solution to obtain the blue light cutoff filter film.

[0032] Optionally, the matrix in step (1) is a polymer;

[0033] The polymer is selected from at least one of polyvinylidene fluoride, polyvinylidene fluoride and trifluoroethylene copolymer, polyacrylonitrile, polyvinyl acetate, cellulose acetate, cyanocellulose, polysulfone, aromatic polyamide, polyimide, polycarbonate, polystyrene, and polymethyl methacrylate.

[0034] Optionally, the precursor solution in step (1) further contains a solvent;

[0035] The solvent is selected from at least one of N,N-dimethylformamide, dimethyl sulfoxide, trimethyl phosphate, triethyl phosphate, N-methylpyrrolidone and dimethylacetamide.

[0036] Optionally, step (1) includes:

[0037] (s11) obtaining a solution containing a matrix;

[0038] (s12) Obtain an ethyl solution containing CH3NH3X and BiX3.

[0039] (s13) Mixing solution A and solution B to obtain the precursor solution.

[0040] Optionally, X in CH3NH3X and BiX3 is at least one of Cl, Br and I.

[0041] Optionally, in the B solution, the molar ratio of BiX3 to CH3NH3X is 1:0.1-3;

[0042] The mass ratio of solvent: (BiX3+CH3NH3X) is 1:0.001~3.

[0043] Optionally, in the B solution, the upper limit of the molar ratio of BiX3 to CH3NH3X is selected from 1:0.3, 1:0.5, 1:0.8, 1:1.0, 1:1.3, 1:1.5, 1:1.8, 1:2.0, 1:2.5, 1:2.8 or 1:3; the lower limit is selected from 1:0.1, 1:0.3, 1:0.5, 1:0.8, 1:1.0, 1:1.3, 1:1.5, 1:1.8, 1:2.0, 1:2.5 or 1:2.8.

[0044] Optionally, in the solution A, the mass ratio of the matrix to the solvent is 1:1-100.

[0045] Optionally, the mass ratio of solution A to solution B is 1:0.02-5.

[0046] Optionally, in the solution A, the mass ratio of the matrix to the solvent is 1:1, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:12, 1:15, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, 1:100 and a range between any two ratios.

[0047] Optionally, in the B solution, the molar ratio of BiX3 to CH3NH3X is 1:0.1, 1:0.4, 1:0.5, 1:0.6, 1:0.75, 1:0.9, 1:1, 1:1.1, 1:1.5, 1:2, 1:3 and a range between any two ratios.

[0048] Optionally, the mass ratio of the acetyl solvent and (BiX3+CH3NH3X) is 1:0.001, 1:0.01, 1:0.03, 1:0.045, 1:0.05, 1:0.1, 1:0.2, 1:0.8, 1:0.9, 1:1, 1:3 and a range value between any two ratios.

[0049] Optionally, in step (s13), the mass ratio of solution A to solution B is 1:0.02, 1:0.1, 1:0.5, 1:0.6, 1:0.8, 1:1, 1:2, 1:3, 1:5 and a range value between any two ratios.

[0050] Optionally, the forming in step (2) includes:

[0051] The precursor solution is transferred to a template and molded to obtain the composite luminescent material.

[0052] Optionally, the transfer comprises at least one of a spin coating method, a dip-pull method, an electrostatic spinning method, a solution sinking method, a spray coating method, a scraping method, and a casting method.

[0053] Optionally,

[0054] The forming in step (2) includes drying;

[0055] The drying conditions include: temperature 40-180° C., time 0.1-48 h.

[0056] Optionally, the drying conditions also include: a pressure of 0.01 to 0.1 MPa.

[0057] Optionally, the upper limit of the drying pressure is selected from 0.02Mpa, 0.03Mpa, 0.04Mpa, 0.05Mpa, 0.06Mpa, 0.07Mpa, 0.08Mpa, 0.09Mpa or 0.1Mpa; the lower limit is selected from 0.01Mpa, 0.02Mpa, 0.03Mpa, 0.04Mpa, 0.05Mpa, 0.06Mpa, 0.07Mpa, 0.08Mpa or 0.09Mpa.

[0058] Optionally, the upper limit of the drying temperature is selected from 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C; the lower limit is selected from 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 110°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C or 170°C.

[0059] Optionally, the upper limit of the drying time is selected from 1h, 2h, 3h, 4h, 5h, 6h, 8h, 10h, 15h, 24h, 28h, 32h, 35h, 40h or 48h; the lower limit is selected from 0.1, 0.5h, 1h, 2h, 3h, 4h, 5h, 6h, 8h, 10h, 15h, 24h, 28h, 32h, 35h or 40h.

[0060] Optionally, the method for preparing the blue light cut-off filter film further comprises the following steps:

[0061] Adhesive is applied to the upper and lower surfaces of the blue light cut-off filter film, and barrier films are laminated respectively.

[0062] Specifically, the method for preparing the blue light cut-off filter film is characterized by comprising the following steps:

[0063] (1) Dissolving the matrix polymer material in a solvent:

[0064] The organic solvent includes at least one of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), trimethyl phosphate (TMP), triethyl phosphate (TEP), N-methyl pyrrolidone (NMP), and dimethylacetamide (DMAc). The matrix is ​​composed of an organic polymer, and the polymer can be at least one of polyvinylidene fluoride (PVDF), polyvinylidene fluoride and trifluoroethylene copolymer (P(VDF-TrFE)), polyacrylonitrile (PAN), polyvinyl acetate (PVAc), cellulose acetate (CA), cyanocellulose (CNA), polysulfone (PSF), aromatic polyamide (PA), polyimide (PI), polycarbonate (PC), polystyrene (PS), and polymethyl methacrylate (PMMA). The mass ratio of the matrix to the organic solvent is 1: (1-50). The matrix material is mixed with the organic solvent and mechanically stirred until the matrix material is completely dissolved in the organic solvent to form a clear and transparent solution.

[0065] The preparation process of solution A is dispersed by a high-speed stirrer. Thus, the uniformity and dispersibility of solution A can be further improved, and the effect of the composite material can be improved. Solution A can be prepared by the following steps: dissolving the matrix and the additive in an organic solvent, the mass ratio of the matrix to the organic solvent is 1: (1-30), the mass ratio of the matrix to the additive is 1: (0.01-0.5), mechanically stirring and mixing for 12 hours, so that the matrix and the additive are completely dissolved in the organic solvent, and a clear and transparent solution is obtained to obtain solution A.

[0066] (2) Obtaining Solution B

[0067] In this step, BiX3 and CH3NH3X are dissolved in an organic solvent to obtain a second solution. The second organic solvent includes at least one selected from DMF, DMSO, TMP, TEP, NMP, and DMAc, and the second organic solvent is miscible with the first organic solvent. It should be noted that the term "miscible" specifically refers to the fact that when the first organic solvent is mixed with the second organic solvent, the mixed solution does not show stratification. Thus, the first solution and the second solution can be mixed to form a unified organic solvent system, that is, the solubility of the raw material components such as BiX3, CH3NH3X and polymer matrix dissolved in the first solution and the second solution in the first organic solvent and the second organic solvent is not significantly different, and no phase separation occurs in the macroscopic and microscopic structures. Among them, the molar ratio of CH3NH3X to BiX3 can be 1: (0.1-3), and the mass ratio of the second organic solvent to (BiX3+CH3NH3X) can be 1: (0.001-1).

[0068] (3) Forming a precursor solution

[0069] According to an embodiment of the present invention, in this step, solution A is mixed with solution B to obtain a precursor solution. Specifically, the mass ratio of solution A to solution B is 1:(0.02-5), and mechanical stirring is performed for 2 hours to obtain a precursor solution.

[0070] (4) Transfer

[0071] In this step, the uniformly mixed precursor solution is transferred to the template by a suitable method to form a thin film anti-blue light layer. Specifically, the method of transferring the precursor solution to the template may include spin coating, immersion pulling, electrospinning, solution sinking, spraying, scraping or casting. Thus, a thin film anti-blue light layer can be easily obtained.

[0072] (5) Drying

[0073] In this step, the template with the precursor solution is dried to obtain the anti-blue light layer. Specifically, the template with the precursor solution attached can be placed in a vacuum drying oven, and the organic solvent in the precursor solution can be removed under certain conditions, thereby controlling the volatilization conditions of the organic solvent system to control the crystallization of the matrix, the nucleation and growth of the quantum dot particles, thereby improving the performance of the anti-blue light layer.

[0074] (6) Packaging

[0075] In this step, the water and oxygen barrier film is combined with the blue light cut-off filter film by gluing, adsorption, coating, etc. to form a sandwich structure material with the blue light cut-off filter film in the middle, thereby enhancing the use stability of the blue light cut-off filter film.

[0076] The barrier film is composed of one or more layers of film with water vapor and oxygen barrier capabilities, and the film material includes but is not limited to PVA coated high barrier film, polyvinylidene chloride, film (PVDC), ethylene / vinyl alcohol copolymer film (EOVH), nylon material, inorganic oxide coating film, etc. The thickness of the barrier film is generally 10-100 μm. The barrier film can adopt an existing barrier film.

[0077] The adhesive is selected from one of polystyrene resin, polymethyl methacrylate, acrylic resin, polyurethane resin and epoxy resin, or a mixture of at least two of them.

[0078] According to another aspect of the present application, a blue light blocking device is provided, characterized in that it contains the blue light cutoff filter film and the blue light cutoff filter film prepared according to the preparation method.

[0079] According to another aspect of the present application, a blue light lighting device is provided, characterized in that it contains the blue light cut-off filter film and the blue light cut-off filter film prepared according to the preparation method.

[0080] According to another aspect of the present application, a blue light protection eyeglass lens is provided, comprising the blue light cut-off filter film and the blue light cut-off filter film prepared according to the preparation method.

[0081] According to another aspect of the present application, a backlight module is provided, characterized in that it contains the blue light cut-off filter film and the blue light cut-off filter film prepared according to the preparation method.

[0082] Optionally, the backlight module is a direct-lit backlight module or an edge-lit backlight module.

[0083] Optionally, the backlight module includes a light-emitting unit, a reflective film, a light-homogenizing component and a blue light cutoff filter film; the reflective film and the light-homogenizing component are arranged opposite to each other and form a light-guiding space;

[0084] The light emitted by the light emitting unit is homogenized in the light guiding space and emitted from the light homogenizing component.

[0085] Optionally, the light uniforming component is in a plate shape and is opposite to the reflective film;

[0086] The light emitting unit is arranged on one side of the light evenly distributed component. The light emitted by the light reflecting unit enters the light evenly distributed component, is reflected by the light reflecting film, and is emitted from the light evenly distributed component.

[0087] Optionally, the light-emitting unit is arranged on the reflective film; the light-emitting film includes a plurality of reflective units; the light-emitting unit includes: a groove structure fixed on the reflective film, a blue LED chip and yellow phosphor fixed in the groove structure, and an arc-shaped prism covering the groove.

[0088] Optionally, the direct-type backlight module comprises, from bottom to top, a reflective film, a diffusion plate, a blue light cut-off filter film, a lower brightness enhancement sheet and an upper brightness enhancement sheet; or

[0089] The direct-type backlight module comprises, from bottom to top, a reflective film, a blue light cut-off filter film, a diffusion plate, a lower brightness enhancement sheet and an upper brightness enhancement sheet; or

[0090] The edge-lit backlight module comprises, from bottom to top, a reflective film, a light guide plate, a blue light cut-off filter film, a lower brightness enhancement sheet and an upper brightness enhancement sheet; or

[0091] The edge-entry backlight module comprises, from bottom to top, a reflective film, a blue light cut-off filter film, a light guide plate, a lower brightness enhancement sheet and an upper brightness enhancement sheet.

[0092] According to another aspect of the present application, a blue light protection display device is provided, which includes, from bottom to top: the direct-type backlight module and the liquid crystal panel.

[0093] Optionally, the liquid crystal panel comprises, from bottom to top, a lower polarizer, a filter, a TFT-LCD and an upper polarizer; or

[0094] The liquid crystal panel includes, from left to right, a lower polarizer, a filter, a TFT-LCD and an upper polarizer.

[0095] In the present application, the term "cut-off depth" refers to the maximum transmittance of light allowed to pass through the cut-off band.

[0096] In this application, "peak transmittance" refers to the highest transmittance of the filter in the passband.

[0097] The beneficial effects of this application include:

[0098] 1) The quantum dots provided in this application have a large cutoff depth, the central wavelength can cover 400-480nm, and it is continuously adjustable within this range. At the same time, it has a very steep absorption cutoff edge, which can ensure that the harmful blue light part (<455nm) is filtered as much as possible, while retaining the harmless blue light part, solving the color cast problem caused by the current anti-blue light technology when filtering out blue light.

[0099] 2) The anti-blue light layer in the anti-blue light film provided in this application adopts in-situ preparation technology. The surface of the filter film produced is smooth and has good repeatability. Compared with the current anti-blue light technology, the preparation process is simpler and faster.

[0100] 3) The surface of the A3Bi2X9 quantum dots provided in this application is coated with a polymer matrix. At the same time, water and oxygen barrier films are adhered to the upper and lower surfaces of the anti-blue light layer. These can further enhance the stability of the A3Bi2X9 quantum dots and promote the practical application of the anti-blue light film. BRIEF DESCRIPTION OF THE DRAWINGS

[0101] Figure 1 The white light spectrum of the blue light LED chip + yellow phosphor backlight display before and after the blue light cutoff filter film is used; (a) is the intensity diagram before and after the blue light is filtered, and (b) is the normalized intensity diagram before and after the blue light is filtered.

[0102] Figure 2 The white light spectrum of the display before and after using the blue light cutoff filter film for the blue light LED chip + green light + red light quantum dot film display.

[0103] Figure 3(a) shows a direct-type backlight structure.

[0104] Figure 3(b) shows the edge-type backlight structure.

[0105] Figure 4 Schematic diagram of the structure of the blue light cutoff filter film based on perovskite quantum dots.

[0106] Figure 5 This is the XRD pattern of sample F-5.

[0107] Figure 6 This is the TEM image of sample F-5.

[0108] Figure 7 : The spectrum of sample F-1 after passing blue light; (a) is the intensity diagram before and after filtering the blue light, and (b) is the normalized intensity diagram before and after filtering the blue light. DETAILED DESCRIPTION

[0109] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0110] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0111] The analysis method in the examples of this application is as follows:

[0112] Fluorescence emission spectroscopy was performed using a FLSP920 fluorescence spectrometer.

[0113] XRD spectra were analyzed using a Shimadzu 6100 X-ray diffractometer.

[0114] TEM images were taken using JEOL JEM-2200FS.

[0115] Example 1

[0116] (1) Dissolve the polymer in an organic solvent, control the polymer: organic solvent mass ratio to be 1:15, and mechanically stir for no less than 6 hours to completely dissolve the polymer in the organic solvent to obtain a clear and transparent solution, which is the formaldehyde solution. The polymer is polymethyl methacrylate (PMMA); the organic solvent is N,N-dimethylformamide (DMF).

[0117] (2) MABr powder and BiBr3 powder are mixed to control the molar ratio of BiBr3:MABr=7:10, and an organic solvent is added to control the mass ratio of organic solvent: (BiBr3+MABr)=1:0.045. After mixing, mechanical stirring is performed for 6 hours to obtain a clear and transparent solution, which is the acetyl solution. The organic solvent in this step is N,N-dimethylformamide (DMF).

[0118] (3) Mixing the solution A described in step (1) with the solution B described in step (2) to control the mass ratio of solution A: solution B = 1:0.5, and mechanically stirring for 12 hours to obtain a uniformly mixed precursor solution.

[0119] (4) Pour the precursor solution described in the above step (3) onto a transparent glass sheet to cast a wet film, and then place the transparent glass sheet coated with the precursor solution in a vacuum drying oven with an air pressure of 0.1 MPa and a temperature of 50° C. for 10 minutes to remove the organic solvent. Then, take the glass sheet with the solvent removed out of the vacuum drying oven and place it on a heating plate at 130° C. for 30 minutes, and then the MA3Bi2Br9 quantum dots are generated in situ in the PMMA matrix.

[0120] (5) Polymethyl methacrylate adhesive and PVA material were used to coat a high-barrier film, a water and oxygen barrier film, to protect the anti-blue light layer, and a blue light cutoff filter film F-1 based on perovskite quantum dots was obtained.

[0121] Anti-blue light film structure Figure 4 As shown, the blue light cutoff filter film based on perovskite quantum dots comprises, from bottom to top: a water and oxygen barrier layer (barrier film), an anti-blue light layer (i.e., a blue light cutoff filter film based on perovskite quantum dots), and a water and oxygen barrier layer.

[0122] Example 2

[0123] The specific operation is the same as that in Example 1, except that the polymer in step (1) is polyvinylidene fluoride (PVDF), and a blue light-proof cutoff filter film F-2 based on perovskite quantum dots is obtained.

[0124] Example 3

[0125] The specific operation is the same as that in Example 1, except that in step (3), the mass ratio of solution A to solution B is 2:1, and a blue light-proof cutoff filter film F-3 based on perovskite quantum dots is obtained.

[0126] Example 4

[0127] The specific operation is the same as that in Example 1, except that in step (3), the mass ratio of solution A:solution B is 1:1, and a blue light-proof cutoff filter film F-4 based on perovskite quantum dots is obtained.

[0128] Example 5

[0129] The specific operation is the same as that in Example 1, except that the polymer in step (1) is polyacrylonitrile (PAN), and the blue light-proof cutoff filter film F-5 based on perovskite quantum dots is obtained.

[0130] Example 6

[0131] XRD analysis was performed on samples F-1 to F-5 prepared in Examples 1 to 5. Typical XRD spectra are shown in Figure 5As shown, corresponding to sample F-5, from the X-ray diffraction data, it can be seen that the MA3Bi2Br9 in the prepared perovskite quantum dot optical film belongs to the trigonal crystal system (P 3m1), among which the diffraction peaks at 8.9°, 17.7° and 26.7° correspond to (001), (002) and (003) in the standard card, respectively. The results show that MA3Bi2Br9 perovskite quantum dots are obtained.

[0132] TEM analysis was performed on samples F-1 to F-5 prepared in Examples 1 to 5. Typical TEM spectra are shown in FIG. Figure 6 As shown, corresponding to sample F-5, the results show that the MA3Bi2Br9 perovskite quantum dots are uniformly distributed in the polymer matrix, making the perovskite quantum dot optical film have higher transparency.

[0133] The samples F-1 to F-5 prepared in Examples 1 to 5 were subjected to spectral analysis. White light passed through the samples F-1 to F-5, and the typical spectra were as follows: Figure 1 and Figure 2 The results show that after the white light passes through F-1 to F-5, the 400nm to 450nm blue light is filtered out, and the 450nm to 500nm blue light passes through.

[0134] The samples F-1 to F-5 prepared in Examples 1 to 5 were subjected to spectral analysis. Blue light passed through the samples F-1 to F-5, and the typical spectra were as follows: Figure 7 The results show that after the blue light passes through F-1 to F-5, the 400nm to 450nm blue light is filtered, the 450nm to 500nm blue light passes, and no other wavelengths of light are generated.

[0135] Example 7

[0136] Samples F-1 to F-5 prepared in Examples 1 to 5 are used for anti-blue light display devices. The structure of the anti-blue light display device is shown in Figure 3(a) (direct-type backlight module). The anti-blue light display device includes, from bottom to top: a direct-type backlight module and a liquid crystal panel; the direct-type backlight module includes a blue light cut-off filter film. The direct-type backlight module includes, from bottom to top: a reflective film, a diffusion plate, a blue light cut-off filter film, a lower brightening film and an upper brightening film. The reflective film includes a plurality of light-emitting units; the light-emitting unit includes: a groove structure fixed on the reflective film, a blue LED chip and yellow phosphor fixed in the groove structure, and an arc prism covering the groove. The liquid crystal panel includes, from bottom to top: a lower polarizer, a filter, a TFT-LCD and an upper polarizer.

[0137] The white light spectrum before and after using the filter film F-1 is as follows Figure 1As shown, the results show that after filtering the blue light, short-wavelength blue light below 450nm is filtered out, and long-wavelength blue light above 450nm is retained.

[0138] Example 8

[0139] Samples F-1 to F-5 prepared in Examples 1 to 5 are used for anti-blue light display devices. The structure of the anti-blue light display device is shown in Figure 3(b). The anti-blue light display device includes, from bottom to top: an edge-entry backlight module and a liquid crystal panel; the edge-entry backlight module includes a blue light cut-off filter film. The edge-entry backlight module includes, from bottom to top: a reflective film, a light guide plate, a blue light cut-off filter film, a lower brightening film and an upper brightening film. The light source of the edge-entry backlight module is arranged on one side of the light guide plate. The liquid crystal panel includes, from bottom to top: a lower polarizer, a filter, a TFT-LCD and an upper polarizer.

[0140] The white light spectrum before and after using the filter film F-1 is as follows Figure 2 As shown, the results show that after filtering the blue light, short-wavelength blue light below 450nm is filtered out, and long-wavelength blue light above 450nm is retained.

[0141] Example 9

[0142] The anti-blue light film described in the present application can be used for anti-blue light glasses. The remaining steps are the same as in Example 1, except that in step (4), the precursor solution is poured on an ordinary lens to cast a wet film, and then the transparent glass sheet coated with the precursor solution is placed in a vacuum drying oven with an air pressure of 0.1 MPa and a temperature of 50°C. It is placed for 10 minutes to remove the organic solvent. The glass sheet with the solvent removed is then taken out of the vacuum drying oven and placed on a heating plate at 130°C for 30 minutes, and MA3Bi2Br9 quantum dots are generated in situ in the PMMA matrix. The anti-blue light layer is protected by coating a high-barrier thin film water and oxygen barrier film with polymethyl methacrylate adhesive and PVA material. The anti-blue light glasses were subjected to a spectral test, and the results showed that after filtering the blue light, short-wavelength blue light below 450nm was filtered out, and long-wavelength blue light above 450nm was retained.

[0143] Example 10

[0144] The anti-blue light film of the present application can be used for anti-blue light lighting devices. The anti-blue light film prepared in Example 1 is adhered to the inside or outside of the lighting device to filter blue light. The anti-blue light lighting device is subjected to a spectrum test, and the results show that after filtering blue light, short-wavelength blue light below 450nm is filtered out, and long-wavelength blue light above 450nm is retained.

[0145] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A blue light cut-off filter film, characterized in that: It includes perovskite quantum dots and a matrix; the central wavelength of the blue light cut-off filter film is between 400 and 480 nm; The perovskite quantum dots include at least one selected from quantum dots having a structural formula shown in Formula I; A3Bi2X9 Formula I Wherein, A is selected from CH3NH2CH3 + 、CH3NH3 + At least one of; X is selected from Cl - Br - ,I - At least one of .

2. The blue light cut-off filter film according to claim 1, characterized in that: The perovskite quantum dots are dispersed in the matrix.

3. The blue light cut-off filter film according to claim 1, characterized in that: The size of the perovskite quantum dots in at least one dimension is 2 to 50 nm.

4. The blue light cut-off filter film according to claim 1, characterized in that: The material of the matrix is ​​a polymer.

5. The blue light cut-off filter film according to claim 1, characterized in that: The material of the matrix is ​​selected from at least one of polyvinylidene fluoride, polyvinylidene fluoride and trifluoroethylene copolymer, polyacrylonitrile, polyvinyl acetate, cellulose acetate, cyanocellulose, polysulfone, aromatic polyamide, polyimide, polycarbonate, polystyrene, and polymethyl methacrylate.

6. The blue light cut-off filter film according to claim 1, characterized in that: The mass ratio of the matrix to the perovskite quantum dots is 1 to 100:

1.

7. The blue light cut-off filter film according to claim 1, characterized in that: The thickness of the blue light cut-off filter film is 0.001-5 mm.

8. The blue light cut-off filter film according to claim 1, characterized in that: The blue light cut-off filter film also includes a barrier film; The barrier film is stacked on the blue light cut-off filter film.

9. The blue light cut-off filter film according to claim 8, characterized in that: At least one barrier film is stacked on the upper and lower surfaces of the blue light cut-off filter film.

10. The blue light cut-off filter film according to claim 8, characterized in that: The material of the barrier film is selected from at least one of a polyvinylidene chloride film, an ethylene-vinyl alcohol copolymer film, a m-dimethylamine and adipic acid condensation polymer film, and an oxide coating film.

11. The blue light cut-off filter film according to claim 8, characterized in that: The thickness of the barrier film is 15um to 500um.

12. The method for preparing the blue light cut-off filter film according to any one of claims 1 to 11, characterized in that: The following steps are involved: The solution containing the perovskite quantum dot precursor and the matrix material is formed and dried to obtain the blue light cut-off filter film.

13. The method for preparing a blue light cut-off filter according to claim 12, characterized in that: The following steps are also included: Adhesive is applied to the upper and lower surfaces of the blue light cut-off filter film, and barrier films are laminated respectively.

14. A blue light protection device, characterized in that: A blue light cut-off filter film comprising the blue light cut-off filter film according to any one of claims 1 to 11 and prepared according to the preparation method according to claim 12 or 13.

15. A blue light protection lighting device, characterized in that: A blue light cut-off filter film comprising the blue light cut-off filter film according to any one of claims 1 to 11 and prepared according to the preparation method according to claim 12 or 13.

16. A blue light blocking glasses lens, characterized in that: A blue light cut-off filter film comprising the blue light cut-off filter film according to any one of claims 1 to 11 and prepared according to the preparation method according to claim 12 or 13.

17. A backlight module, characterized in that: A blue light cut-off filter film comprising the blue light cut-off filter film according to any one of claims 1 to 11 and prepared according to the preparation method according to claim 12 or 13.

18. The backlight module according to claim 17, characterized in that: The backlight module is a direct-lit backlight module or an edge-lit backlight module.

19. The backlight module according to claim 17, characterized in that: The backlight module includes a light-emitting unit, a reflective film, a light-homogenizing component and a blue light cut-off filter film; the reflective film and the light-homogenizing component are arranged opposite to each other and form a light-guiding space; The light emitted by the light emitting unit is homogenized in the light guiding space and emitted from the light homogenizing component.

20. The backlight module according to claim 19, characterized in that: The light uniforming component is in the shape of a plate and is opposite to the reflective film; The light emitting unit is arranged at one side of the light evenly distributed component. The light emitted by the light emitting unit enters the light evenly distributed component, is reflected by the reflective film, and is emitted from the light evenly distributed component.

21. The backlight module according to claim 19, characterized in that: The light-emitting unit is arranged on the reflective film; the reflective film includes a plurality of reflective units; the light-emitting unit includes: a groove structure fixed on the reflective film, a blue LED chip and yellow phosphor fixed in the groove structure, and an arc prism covering the groove.

22. The backlight module according to claim 18, characterized in that: The direct-type backlight module comprises, from bottom to top, a reflective film, a diffusion plate, a blue light cut-off filter film, a lower brightness enhancement sheet and an upper brightness enhancement sheet; or The direct-type backlight module comprises, from bottom to top, a reflective film, a blue light cut-off filter film, a diffusion plate, a lower brightness enhancement sheet and an upper brightness enhancement sheet; or The edge-lit backlight module comprises, from bottom to top, a reflective film, a light guide plate, a blue light cut-off filter film, a diffusion film, a lower brightness enhancement sheet and an upper brightness enhancement sheet; or The edge-entry backlight module comprises, from bottom to top, a reflective film, a light guide plate, a diffusion film, a blue light cut-off filter film, a lower brightness enhancement sheet and an upper brightness enhancement sheet.

23. A blue light protection display device, characterized in that: include: The backlight module according to any one of claims 17 to 22; and LCD panel.

24. The blue light protection display device according to claim 23, characterized in that: The liquid crystal panel comprises, from bottom to top, a lower polarizing plate, a filter, a TFT-LCD and an upper polarizing plate.

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