Light-absorbing material, preparation method thereof and display device

Abstract

The invention relates to a light-absorbing material, a preparation method thereof and a display device. The light absorbing material is selected from at least one of structures shown in a formula (1): (1); wherein R is independently selected from substituent groups with 1-6 hydrogen atoms or carbon atoms; the light absorbing material has a maximum absorption wavelength in a wavelength range of 600 nm to 1100 nm. The invention provides a near-infrared light absorbing material which can cover a wave band of 600 nm to 1100 nm and has good solubility.

Description

Technical Field

[0001] This application relates to the field of display technology, specifically to a light-absorbing material, its preparation method, and a display device. Background Technology

[0002] With the development of display technology, the requirements for image quality of display devices are constantly increasing, especially in terms of color reproduction, contrast and ambient light adaptability.

[0003] In practical applications, near-infrared light from ambient light or display backlight often interferes with display performance, leading to problems such as color distortion and decreased contrast. Therefore, incorporating a filter film capable of selectively absorbing infrared light into display devices has become a crucial technical means to improve display performance.

[0004] In recent years, organic light-absorbing materials have gradually become a research hotspot due to their advantages such as tunable structure, controllable absorption bands, good compatibility with polymer substrates, and simple processing technology. Among them, porphyrins and their derivatives are regarded as potential broadband light-absorbing materials due to their unique conjugated macrocyclic structure and good photoelectric properties. Traditional porphyrin materials have significant absorption in the blue-green light region, but their absorption in the near-infrared region is weak, making it difficult to meet the requirements of full-band infrared filtering.

[0005] Therefore, there is an urgent need in this field to develop a new type of light-absorbing material that has the advantage of good molecular solubility and can effectively redshift its absorption spectrum to the more practical near-infrared band. Summary of the Invention

[0006] This application provides a light-absorbing material, its preparation method, and a display device, aiming to provide a near-infrared light-absorbing material that can cover the 600nm to 1100nm wavelength band and has good solubility.

[0007] This application provides a light-absorbing material, comprising: the light-absorbing material being selected from at least one of the structures shown in formula (1): (1); Wherein, R is independently selected from hydrogen atoms or substituents having 1 to 6 carbon atoms; the light-absorbing material has a maximum absorption wavelength in the wavelength range of 600 nanometers to 1100 nanometers.

[0008] In some embodiments of this application, the R is independently selected from alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 3 to 6 carbon atoms, alkenyl groups having 2 to 6 carbon atoms, alkynyl groups having 2 to 6 carbon atoms, aryl or heteroaryl groups having 6 cyclic atoms, alkylamino groups having 1 to 2 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, alkylthio groups having 1 to 6 carbon atoms, or cyano groups having 1 to 6 carbon atoms; at least one hydrogen atom on the alkyl group is not substituted or is substituted by a halogen atom.

[0009] In some embodiments of this application, R is independently selected from methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isopropyl, isobutyl, sec-butyl, tert-butyl, neopentyl, isopentyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 1,3-butadienyl, ethynyl, 1-propynyl, 2-propynyl, methylamino, ethylamino, dimethylamino, diethylamino, phenyl, alkoxy, ethoxy, propoxy, butoxy, methylthio, ethylthio, cyano, trifluoromethyl, trichloromethyl, or 2,2,2-trifluoroethyl.

[0010] In some embodiments of this application, the R is selected from hydrogen atom, tert-butyl, n-butyl or n-hexyl, and different R are selected from the same group.

[0011] In some embodiments of this application, the light-absorbing material has a maximum absorption wavelength in the wavelength range of 700 nm to 730 nm and in the range of 980 nm to 1020 nm.

[0012] On the other hand, this application also provides a method for preparing a light-absorbing material, comprising: mixing a carbazole diboronic acid ester with a substituent R, dibromothiophene, a palladium catalyst, a base, and a first solvent to form a mixed solution; wherein, the R is independently selected from a substituent having 1 to 6 hydrogen atoms or carbon atoms; heating the mixed solution under the protection of an inert gas to obtain an intermediate; and mixing the intermediate, an oxidant, and a second solvent to obtain the light-absorbing material as described above.

[0013] In some embodiments of this application, the palladium catalyst is selected from at least one of bis(triphenylphosphine)palladium dichloride, tetra(triphenylphosphine)palladium, tris(dibenzylideneacetone)palladium, and 1,1'-bis(diphenylphosphine)ferrocenepalladium dichloride.

[0014] In some embodiments of this application, the alkali is selected from at least one of potassium carbonate, potassium phosphate, cesium carbonate, potassium fluoride, and cesium fluoride.

[0015] In some embodiments of this application, the first solvent is selected from at least one of toluene, N,N-dimethylformamide, 1,4-dioxane, and tetrahydrofuran.

[0016] In some embodiments of this application, the oxidant is selected from at least one of manganese dioxide, lead dioxide, and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone.

[0017] In some embodiments of this application, the second solvent is selected from at least one of dichloromethane and chloroform.

[0018] In some embodiments of this application, the heating time for the mixed solution ranges from 24 hours to 48 hours, and the heating temperature is greater than or equal to the boiling point of the solvent.

[0019] In addition, this application also provides a display device, including a display panel and a filter film disposed on at least one side or inside the display panel; the material of the filter film includes the aforementioned light-absorbing material or a light-absorbing material prepared by the aforementioned preparation method.

[0020] In some embodiments of this application, the mass fraction of the light-absorbing material in the filter film ranges from 0.3% to 3.0%.

[0021] The light-absorbing material, its preparation method, and the display device provided in this application possess a porphyrin-like macrocyclic structure. By introducing carbazole and thiophene units, it achieves strong absorption characteristics in the wavelength range of 600 nm to 1100 nm. This structural design extends the absorption spectrum of traditional porphyrin materials to the near-infrared region, making it suitable for the field of infrared light-absorbing materials. Simultaneously, the R substituents provide a structural basis for subsequent adjustment of solubility, spectral performance, and stability, resulting in excellent solubility, spectral performance, and stability of the light-absorbing material. Therefore, this application provides a light-absorbing material that can cover the 600 nm to 1100 nm wavelength band and has good solubility. Attached Figure Description

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

[0023] Figure 1 This is a schematic flowchart of a method for preparing a light-absorbing material provided in an embodiment of this application.

[0024] Figure 2 This is a schematic diagram of the structure of a display device provided in an embodiment of this application.

[0025] Figure 3 This is the ultraviolet-visible absorption spectrum of the compound represented by formula A provided in the embodiments of this application.

[0026] Figure 4 This is the ultraviolet-visible absorption spectrum of the compound represented by formula B provided in the embodiments of this application.

[0027] Figure 5 This is the ultraviolet-visible absorption spectrum of the compound represented by formula C provided in the embodiments of this application.

[0028] Figure 6 This is the ultraviolet-visible absorption spectrum of the compound represented by formula D provided in the embodiments of this application.

[0029] Figure 7 This is the UV-Vis absorption spectrum of the compound represented in the comparative example of this application.

[0030] Figure 8 This is the transmission spectrum of the filter film formed by the compound represented by formula A provided in the embodiments of this application.

[0031] Figure 9 This is the transmission spectrum of the filter film formed by the compound represented by formula B provided in the embodiments of this application.

[0032] Figure 10 This is the transmission spectrum of the filter film formed by the compound represented by formula C provided in the embodiments of this application.

[0033] Figure 11 This is the transmission spectrum of the filter film formed by the compound represented by formula D provided in the embodiments of this application.

[0034] Explanation of reference numerals in the attached drawings: 1. Display device; 2. Display panel; 3. Filter film. Detailed Implementation

[0035] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] This application provides a light-absorbing material, a method for preparing the same, and a display device. These are described in detail below. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc., are used merely as illustrative and do not impose numerical requirements or establish an order. Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single digits within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any referenced number (fraction or integer) within the indicated range.

[0037] Materials with poor solubility are generally difficult to formulate into uniform and stable solutions or dispersions. This directly prevents the application of modern, efficient, and low-cost solution processing techniques such as spin coating, doctor blade coating, inkjet printing, and roll-to-roll printing. For light-absorbing materials with poor solubility, complex, expensive, and energy-intensive processes such as vacuum evaporation and vapor deposition are required, significantly increasing equipment investment and production costs. Furthermore, even when solution processes are used, insufficient dissolution can lead to the formation of aggregates, particles, or pinholes in the film, resulting in uneven film, poor light transmittance, and a rough surface, severely impacting the optical performance and reliability of the final product. In the preparation of composite materials, such as when light-absorbing materials are incorporated into resins to create filter films, poor solubility means the material is difficult to disperse uniformly in the matrix, easily leading to phase separation, sedimentation, or aggregation, resulting in large batch-to-batch variations in product quality and unstable performance. When using light-absorbing materials with low solubility to prepare filter films, the light-absorbing material cannot be uniformly dispersed in UV adhesives or resins, resulting in problems such as significant visible light scattering loss and uneven near-infrared absorption in the prepared filter film.

[0038] To address the aforementioned problems, this application provides a novel light-absorbing material that exhibits a maximum absorption wavelength in the wavelength range of 600 nm to 1100 nm and also possesses good solubility. See the following description of specific embodiments.

[0039] This application provides a light-absorbing material selected from at least one of the structures shown in formula (1): (1); R is independently selected from hydrogen atoms or substituents having 1 to 6 carbon atoms; the light-absorbing material has a maximum absorption wavelength in the wavelength range of 600 nm to 1100 nm.

[0040] It is understood that the light-absorbing material provided in this application has a porphyrin-like macrocyclic structure. By introducing carbazole and thiophene units, it achieves strong absorption characteristics in the wavelength range of 600 nm to 1100 nm. This structural design extends the absorption spectrum of traditional porphyrin materials to the near-infrared region, making it suitable for the field of infrared light-absorbing materials. Simultaneously, the R substituents provide a structural basis for subsequent adjustment of solubility, spectral performance, and stability, resulting in good solubility, spectral performance, and stability of the light-absorbing material. Therefore, this application provides a light-absorbing material that can cover the 600 nm to 1100 nm wavelength band and has good solubility.

[0041] In some embodiments of this application, R is independently selected from alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 3 to 6 carbon atoms, alkenyl groups having 2 to 6 carbon atoms, alkynyl groups having 2 to 6 carbon atoms, aryl or heteroaryl groups having 6 cyclic atoms, alkylamino groups having 1 to 2 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, alkylthio groups having 1 to 6 carbon atoms, or cyano groups having 1 to 6 carbon atoms; at least one hydrogen atom on the alkyl group is not substituted or is substituted by a halogen atom.

[0042] It is understandable that by adjusting the chemical structure and properties of the R group, the solubility, molecular packing mode and electronic structure of the light-absorbing material can be effectively controlled, thereby optimizing its absorption performance and processing applicability in solution and solid film.

[0043] In some embodiments of this application, R is independently selected from methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isopropyl, isobutyl, sec-butyl, tert-butyl, neopentyl, isopentyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 1,3-butadienyl, ethynyl, 1-propynyl, 2-propynyl, methylamino, ethylamino, dimethylamino, diethylamino, phenyl, alkoxy, ethoxy, propoxy, butoxy, methylthio, ethylthio, cyano, trifluoromethyl, trichloromethyl, or 2,2,2-trifluoroethyl, but is not limited thereto.

[0044] Understandably, R enhances the material's solubility in common organic solvents while maintaining its absorption performance, which is beneficial for subsequent film formation and applications.

[0045] In some embodiments of this application, R is selected from hydrogen atom, tert-butyl, n-butyl or n-hexyl, and different R are selected from the same group.

[0046] It is understandable that using highly symmetric R substituents in light-absorbing materials helps improve the efficiency of material synthesis and purification, as well as structural consistency, thereby ensuring the stability and reproducibility of the absorption spectrum. Of course, the light-absorbing materials protected in this application are not limited to the four types and combinations mentioned above.

[0047] In some embodiments of this application, the light-absorbing material has a maximum absorption wavelength in the wavelength range of 700 nm to 730 nm and in the range of 980 nm to 1020 nm.

[0048] It is understandable that there can be one or more maximum absorption wavelengths. Multiple maximum absorption wavelengths occur because the corresponding spectrum has multiple absorption peaks, each corresponding to a maximum absorption wavelength. The light-absorbing material covers the visible to near-infrared band, making it suitable for optical filtering applications requiring broad-spectrum absorption.

[0049] Specifically, the light-absorbing material provided in this application embodiment can be applied to structures such as infrared cut-off filters, automotive windshields, building windows, and display devices to achieve the effect of blocking heat while maintaining high visible light transmittance. Of course, the light-absorbing material provided in this application embodiment can also be used as a color resist material or a photoresponsive material, etc.

[0050] On the other hand, such as Figure 1 As shown in the embodiments of this application, a method for preparing a light-absorbing material is also provided, comprising the following steps: S100: A mixed solution is formed by mixing a carbazole diboronic acid ester with a substituent R, dibromothiophene, a palladium catalyst, a base, and a first solvent; wherein R is independently selected from hydrogen atoms or substituents having 1 to 6 carbon atoms. S200: The mixed solution is heated under the protection of an inert gas to obtain an intermediate; and S300: The intermediate, oxidant and second solvent are mixed and treated to obtain the light-absorbing material as described above.

[0051] It is understood that the preparation method of this application involves the synthesis of a porphyrin-like intermediate via palladium-catalyzed Suzuki coupling, followed by oxidative dehydrogenation to obtain the final product. This method has advantages such as mild reaction conditions, well-defined product structure, and ease of purification. The specific reaction pathway for the light-absorbing material is as follows: .

[0052] In some embodiments of this application, the palladium catalyst is selected from at least one of bis(triphenylphosphine)palladium dichloride, tetra(triphenylphosphine)palladium, tris(dibenzylideneacetone)palladium, and 1,1'-bis(diphenylphosphine)ferrocenepalladium dichloride, but is not limited thereto.

[0053] Understandably, the catalysts in this application can effectively catalyze the C–C bond coupling between carbazole diboronate and dibromothiophene to form a porphyrin-like macrocyclic intermediate. These catalysts exhibit high catalytic activity and selectivity, enabling efficient coupling under mild conditions, which helps improve the yield and purity of the intermediate.

[0054] In some embodiments of this application, the alkali is selected from at least one of potassium carbonate, potassium phosphate, cesium carbonate, potassium fluoride, and cesium fluoride, but is not limited thereto.

[0055] Understandably, the base plays a role in promoting the activation of borate esters and neutralizing the byproduct hydrogen halide in the reaction. The base in this application has suitable basicity and solubility, which can effectively promote the coupling reaction. Among them, strong bases such as cesium carbonate and cesium fluoride are particularly suitable for difficult reaction systems, and can improve the reaction rate and conversion rate.

[0056] In some embodiments of this application, the first solvent is selected from at least one of toluene, N,N-dimethylformamide, 1,4-dioxane and tetrahydrofuran, but is not limited thereto.

[0057] Understandably, the first solvent in this application possesses good solubility and suitable boiling point, meeting the reflux temperature requirements of the palladium-catalyzed coupling reaction. A mixed solvent system (such as toluene and DMF) can balance the solubility and reactivity of the reactants, which is beneficial for improving reaction uniformity and efficiency.

[0058] In some embodiments of this application, the heating time for the mixed solution ranges from 24 to 48 hours, and the heating temperature is greater than or equal to the boiling point of the solvent.

[0059] Understandably, prolonged heat treatment ensures a complete reaction and increases conversion rate. Heating to the solvent's boiling point allows for reflux, which helps maintain the activity and stability of the reaction system. A longer reaction time helps overcome steric hindrance and entropy disadvantages in macrocyclic synthesis, promoting complete cyclization.

[0060] Specifically, the boiling point of toluene at normal pressure is 110.6°C, the boiling point of N,N-dimethylformamide at normal pressure is 153°C, the boiling point of 1,4-dioxane at normal pressure is 101°C, and the boiling point of tetrahydrofuran at normal pressure is 66°C.

[0061] In some embodiments of this application, the inert gas in S200 is selected from at least one of nitrogen and argon, but is not limited thereto.

[0062] In some embodiments of this application, the oxidant is selected from at least one of manganese dioxide, lead dioxide, and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, but is not limited thereto.

[0063] Understandably, the oxidants in this application are suitable for selective oxidative dehydrogenation reactions in aromatic systems, capable of converting partially saturated carbon-carbon bonds in intermediates into conjugated double bonds, thereby expanding the conjugated system and achieving a red shift in the absorption spectrum. These oxidants offer mild conditions and good selectivity, which is beneficial for maintaining the stability of the molecular skeleton.

[0064] In some embodiments of this application, the second solvent is selected from at least one of dichloromethane and chloroform, but is not limited thereto.

[0065] It is understandable that dichloromethane and chloroform have good solubility for both intermediates and oxidants, and have low boiling points, which facilitates oxidation reactions at room temperature or under mild heating conditions. The low polarity of the solvents also helps to avoid side reactions and improve the selectivity of the oxidation step and the purity of the product.

[0066] In some embodiments of this application, the reaction time of S300 is 6 to 12 hours.

[0067] Specifically, the response time of S300 includes any value or any two values ​​among 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours and 12 hours.

[0068] In addition, such as Figure 2 As shown, this application embodiment also provides a display device 1, which includes a display panel 2 and a filter film 3 as described in the foregoing embodiment, wherein the filter film 3 is located on at least one side or inside the display panel 2.

[0069] In some embodiments, the light-emitting device in the display panel 2 includes OLED or LED, but is not limited thereto.

[0070] Understandably, this filter film utilizes the strong infrared absorption characteristics of light-absorbing materials to effectively filter out infrared light in the 600nm to 1100nm wavelength band, making it suitable for suppressing infrared interference and improving color purity in display devices.

[0071] In some embodiments, the light filter 3 is disposed on the light-emitting side of the display panel 2 to suppress infrared components in ambient light.

[0072] In some embodiments, the filter film 3 is disposed inside the display panel 2 to suppress infrared components in ambient light or backlight.

[0073] In some embodiments, the filter film 3 is disposed on the back of the display panel 2 to suppress infrared components in the backlight.

[0074] In some embodiments, the display device 1 further includes a backlight module disposed on the back of the display panel 2, and a filter film 3 is disposed between the display panel 2 and the backlight module, or the filter film 3 is disposed in the backlight module to suppress infrared components in the backlight.

[0075] In this embodiment, the display device 1, by integrating a filter film 3, can effectively suppress infrared components in ambient light or backlight, thereby improving the contrast and color accuracy of the displayed image, and is suitable for display scenarios with high color gamut and low interference.

[0076] In some embodiments of this application, the mass fraction of light-absorbing material in the filter film ranges from 0.3% to 3.0%.

[0077] It is understandable that by controlling the amount of light-absorbing material added to the filter film, an ideal filtering effect can be achieved without affecting the film's transparency, balancing light transmittance and infrared absorption performance. The mass fraction of the light-absorbing material can be any value or a range of any two values ​​from 0.3%, 0.5%, 0.7%, 0.9%, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, 2.0%, 2.0%, 2.2%, 2.4%, 2.6%, 2.8%, and 3.0%.

[0078] Specifically, the methods for manufacturing the filter film include: The light-absorbing material is uniformly dispersed and dissolved in the semi-cured UV adhesive to form a light-filtering coating. Based on 100% by mass, the light-filtering coating includes resin, monomer, leveling agent, dispersant, solvent, and light-absorbing material. Specifically, the mass fraction of resin ranges from 20.0% to 25.0%; the mass fraction of monomer ranges from 5.0% to 10.0%; the mass fraction of leveling agent ranges from 0.1% to 0.5%; the mass fraction of dispersant ranges from 0.1% to 0.5%; the mass fraction of solvent ranges from 61.0% to 74.5%; and the mass fraction of light-absorbing material ranges from 0.3% to 3.0%.

[0079] Specifically, the resin can be (Kyoei Chemicals UA-306H), but is not limited to this. The monomer can be pentaerythritol hexaacrylate (CAS No. 29570-58-9), but is not limited to this. The leveling agent can be BYK-3931P from BYK Chemicals, but is not limited to this. The dispersant can be BYK-2013 from BYK Chemicals, but is not limited to this. The solvent can be ethyl acetate (CAS No. 141-78-6), but is not limited to this.

[0080] The filter coating is obtained by coating, leveling, heating and UV curing the filter coating liquid.

[0081] Specifically, the light-filtering coating obtained in this application is applied to a PET substrate to form a near-infrared absorbing coating with a thickness of 5 μm. This coating can be directly bonded to a display device and can effectively reduce the transmission of near-infrared light. This coating can be combined with anti-reflective coatings, hard coatings, etc., to form a composite film.

[0082] This application also describes the specific preparation process of the four light-absorbing materials represented by formulas A to D through specific embodiments, and tests the solubility of these four light-absorbing materials.

[0083] Example 1 The synthesis process of the compound represented by formula A is as follows: Step 1: Add 1,8-diboron pinacol ester-9H-carbazole (0.2 mmol, CAS No. 1393113-41-1), 2,5-dibromothiophene (0.2 mmol, CAS No. 3141-27-3), tetrakis(triphenylphosphine)palladium (0.02 mmol, CAS No. 14221-01-3), cesium carbonate (0.7 mmol, CAS No. 534-17-8), and cesium fluoride (0.7 mmol, CAS No. 77) to the following solutions: 83-64-4), toluene (5 mL, CAS No. 108-88-3), and N,N-dimethylformamide (5 mL, CAS No. 68-12-2) were mixed in a reaction flask. The reaction flask was evacuated and filled with nitrogen. The reaction solution was heated to 110°C and stirred for 48 hours. After the reaction was cooled to room temperature, it was extracted, washed with water, dried, and concentrated to obtain a crude product. The crude product was then separated by silica gel column chromatography to obtain a yellow powder with a yield of 28%.

[0084] The chemical structure of the yellow powder obtained in step 1 was analyzed, and the results are as follows: 1H NMR spectrum 1 HNMR (CDCl3, 400HMz): 10.25 (s, 2H), 8.12 (s, 4H), 7.76 (s, 4H), 7.41 (s, 4H); Mass spectrometry (MS): 494.0911 [M+H] + ]; Elemental analysis: Elem.Ana.: C 77.710, H 3.67, N 5.66.

[0085] Based on the above test results, it can be confirmed that the product is the compound represented by intermediate I.

[0086] The compound represented by intermediate I is as follows: Intermediate I.

[0087] Step 2: Mix intermediate I (2 mmol), manganese dioxide (1 mmol, CAS No. 1313-13-9) and dichloromethane (5 mL, CAS No. 75-09-2) and stir at room temperature for 12 hours; filter to remove insoluble matter to obtain crude product, then purify by silica gel column chromatography, and finally recrystallize with chloroform to obtain dark green solid product with a yield of 42%.

[0088] The chemical structure of the obtained dark green solid was analyzed, and the results are as follows: 1H NMR spectrum 1 HNMR (CDCl3, 400HMz): 9.87 (s, 4H), 9.40 (s, 4H), 8.86 (s, 4H); Mass spectrometry (MS): 492.0752 [M+H] + ]; Elemental analysis: Elem.Ana.: C 78.03, H 3.27, N 5.69.

[0089] Based on the above test results, it can be confirmed that the product is the compound represented by formula A.

[0090] The compound represented by formula A is as follows: Formula A.

[0091] like Figure 3 As shown, the maximum absorption wavelengths of the compound represented by Formula A are at approximately 713 nm and 1000 nm.

[0092] Example 2 The synthesis process of the compound represented by formula B is as follows: Step 1: The synthesis method and reaction dosage of intermediate II are the same as those of intermediate I in Example 1. Accordingly, the reactants were changed from 3,6-dimethyl-1,8-diborate pinacol ester-9H-carbazole to 3,6-di-tert-butyl-1,8-diborate pinacol ester-9H-carbazole (CAS No. 1263359-87-0); the product obtained was a yellow powder with a yield of 20%.

[0093] The chemical structure of the obtained yellow powder was analyzed, and the results are as follows: 1H NMR spectrum 1 HNMR (CDCl3, 400HMz): 10.27 (s, 2H), 8.13 (s, 4H), 7.79 (s, 4H), 7.44 (s, 4H), 1.54 (s, 36H); Mass spectrometry (MS): 718.3412 [M+H] + ]; Elemental analysis: Elem.Ana.: C 80.16, H 7.04, N 3.90.

[0094] Based on the above test results, it can be confirmed that the product is the compound represented by intermediate II.

[0095] The compounds represented by intermediate II are as follows: Intermediate II.

[0096] Step 2: The synthesis method and reaction amounts of the compound represented by Formula B are the same as those for the compound of Formula A in Example 1. Accordingly, intermediate I is replaced with intermediate II as the reactant. The product obtained is a dark green solid with a yield of 39%.

[0097] The chemical structure of the obtained dark green solid was analyzed, and the results are as follows: 1H NMR spectrum 1 HNMR (CDCl3, 400HMz): 9.90 (s, 4H), 9.44 (s, 4H), 8.87 (s, 4H), 1.54 (s, 36H); Mass spectrometry (MS): 716.3255 [M+H] + ]; Elemental analysis: Elem.Ana.: C 80.36, H 6.77, N 3.90.

[0098] Based on the above test results, it can be confirmed that the product is the compound represented by formula B.

[0099] The compound represented by formula B is as follows: Formula B.

[0100] like Figure 4 As shown, the maximum absorption wavelengths of the compound represented by formula B are at approximately 718 nm and 1008 nm.

[0101] Example 3 The synthesis process of the compound represented by formula C is as follows: Step 1: The synthesis method and reaction amounts of intermediate III are the same as those of intermediate I in Example 1. Accordingly, the reactants were changed from 1,8-diboronic acid pinacol ester-9H-carbazole to 3,6-di-n-butyl-1,8-diboronic acid pinacol ester-9H-carbazole (CAS No. 2959463-47-7); the product obtained was a yellow powder with a yield of 28%.

[0102] The chemical structure of the obtained yellow powder was analyzed, and the results are as follows: 1H NMR spectrum 1 HNMR (CDCl3, 400HMz): 10.26 (s, 2H), 8.12 (s, 4H), 7.82 (s, 4H), 7.45 (s, 4H), 3.12 (t, 8H), 1.56 (m, 8H), 1.42 (m, 8H), 0.88 (t, 12H); Mass spectrometry (MS): 719.3553 [M+H] + ]; Elemental analysis: Elem.Ana.: C 80.18, H 7.00, N 3.90.

[0103] Based on the above test results, it can be confirmed that the product is the compound represented by intermediate III.

[0104] The compounds represented by intermediate III are as follows: Intermediate III.

[0105] Step 2: The synthesis method and reaction amounts of the compound represented by Formula C are the same as those for the compound of Formula A in Example 1. Accordingly, intermediate I is replaced with intermediate III as the reactant. The product obtained is a dark green solid with a yield of 40%.

[0106] The chemical structure of the obtained dark green solid was analyzed, and the results are as follows: 1H NMR spectrum 1 HNMR (CDCl3, 400HMz): 9.91 (s, 4H), 9.42 (s, 4H), 8.86 (s, 4H), 3.15 (t, 8H), 1.57 (m, 8H), 1.42 (m, 8H), 0.89 (t, 12H); Mass spectrometry (MS): 717.3396 [M+H] + ]; Elemental analysis: Elem.Ana.: C 80.44, H 6.75, N 3.90.

[0107] Based on the above test results, it can be confirmed that the product is the compound represented by formula C.

[0108] The compounds represented by formula C are as follows: Formula C.

[0109] like Figure 5 As shown, the maximum absorption wavelengths of the compound represented by formula C are at approximately 727 nm and 1017 nm.

[0110] Example 4 The synthesis process of the compound represented by formula D is as follows: Step 1: The synthesis method and reaction amounts of intermediate IV are the same as those for intermediate I in Example 1. Accordingly, the reactants were changed from 3,6-dimethyl-1,8-diborate pinacol ester-9H-carbazole to 3,6-di-n-hexyl-1,8-diborate pinacol ester-9H-carbazole (CAS No. 2959463-51-3). The resulting product was a yellow powder with a yield of 26%.

[0111] The chemical structure of the yellow powder obtained in step 1 was analyzed, and the results are as follows: 1H NMR spectrum 1HNMR (CDCl3, 400HMz): 10.24 (s, 2H), 8.15 (s, 4H), 7.83 (s, 4H), 7.45 (s, 4H), 3.13 (t, 8H), 1.25 (m, 32H), 0.88 (t, 12H); Mass spectrometry (MS): 831.4667 [M+H] + ]; Elemental analysis by Elem Ana: C 80.96, H 8.00, N 3.38.

[0112] Based on the above test results, it can be confirmed that the product is the compound represented by intermediate IV.

[0113] The compounds represented by intermediate IV are as follows: Intermediate IV.

[0114] Step 2: The synthesis method and reaction amounts of the compound represented by Formula D are the same as those of the compound of Formula A in Example 1. Accordingly, intermediate I is replaced with intermediate IV as the reactant, and the product obtained is a dark green solid with a yield of 39%.

[0115] The chemical structure of the obtained dark green solid was analyzed, and the results are as follows: 1H NMR spectrum 1 HNMR (CDCl3, 400HMz): 9.90 (s, 4H), 9.40 (s, 4H), 8.88 (s, 4H), 3.14 (t, 8H), 1.24 (m, 32H), 0.89 (t, 12H); Mass spectrometry (MS): 829.4671 [M+H] + ]; Elemental analysis: Elem.Ana.: C 81.11, H 7.78, N 3.38.

[0116] Based on the above test results, it can be confirmed that the product is the compound represented by formula D.

[0117] The compound represented by formula D is as follows: Formula D.

[0118] like Figure 6 As shown, the maximum absorption wavelengths of the compound represented by formula D are at approximately 727 nm and 1018 nm.

[0119] Comparative Example 1 Commercially available tetraphenylporphyrin is used, with the following chemical formula: .

[0120] like Figure 7As shown, the maximum absorption wavelength of the compound represented by Comparative Example 1 is between approximately 400 nm and 500 nm.

[0121] This application uses the compounds provided in Examples 1 to 4 to prepare filter films, and the method for preparing the filter films includes: The light-absorbing material is uniformly dispersed and dissolved in the semi-cured UV adhesive. The components and mass fractions of the semi-cured UV adhesive, based on 100% of its mass, are shown below: (1) Resin: Acrylic resin prepolymer (Kyoeisha Chemical, UA-306H), mass fraction 25.0%; (2) Monomer: Dipentaerythritol hexaacrylate (CAS No. 29570-58-9), mass fraction 10.0%; (3) Leveling agent (BYK Chemicals, BYK-3931P), mass fraction 0.2%; (4) Dispersant (BYK Chemicals, BYK-2013), mass fraction 0.1%; (5) Solvent: Ethyl acetate (CAS No. 141-78-6), mass fraction 62.7%; (6) Light-absorbing material, with a mass fraction of 2.0%; The filter coating is obtained by coating, leveling, heating and UV curing the filter coating liquid.

[0122] This application uses a UV-Vis spectrophotometer (Shimidzu UV-2600) to test the transmission spectrum of the prepared filter film, and the results are as follows. Figures 8 to 11 As shown.

[0123] This application also provides for the ultraviolet-visible absorption spectra and solubility of the compounds prepared in Examples 1 to 4.

[0124] UV-Vis absorption spectroscopy test: The compounds prepared in Examples 1 to 4 were formulated into 1×10⁻⁶ ppm solutions. - 6 The UV-Vis absorption spectra of each material were obtained using a UV-Vis spectrophotometer (Shimidzu UV-2600) with a xylene solution of mol / L.

[0125] Solubility test: The compounds prepared in Examples 1 to 4 were quantitatively placed in bottles, and solvent was gradually added until the material was completely dissolved. The solubility was graded, and the results are shown in Table 1.

[0126] in, ≥20mmol / L; ○: 15 mmol / L to 20 mmol / L; △: 5 mmol / L to 15 mmol / L; ×: ≤5mmol / L.

[0127] Table 1

[0128] contrast Figures 3 to 7 It is known that the compounds of formulas A to D prepared in Examples 1 to 4 of this application all show significant absorption peaks around 700 nm to 730 nm and around 1000 nm to 1020 nm, while the tetraphenylporphyrin corresponding to Comparative Example 1 has very weak or almost no absorption in the near-infrared region (>700 nm). This indicates that the light-absorbing material provided in this application significantly expands the conjugated system and changes the electron cloud distribution by introducing fused-ring carbazole units and thiophene heteroatoms, resulting in a sharp redshift in the absorption spectrum and successfully extending the strong absorption to the near-infrared region, giving the light-absorbing material of this application an optical advantage.

[0129] At the same time, in comparison Figures 3 to 6 It can be seen that as the R group in the light-absorbing material changes from hydrogen atom (R group in the compound shown in Formula A) to tert-butyl (R group in the compound shown in Formula B), n-butyl (R group in the compound shown in Formula C), and n-hexyl (R group in the compound shown in Formula D), the wavelengths of the two main absorption peaks shift slightly. This may be due to the slight influence of the electronic and steric effects of different alkyl chains on intramolecular charge transfer and aggregation state. However, the spectral shapes of these materials remain basically consistent, indicating that their core chromophore structure is stable, and the R group mainly plays a solubility modification role rather than significantly altering the photophysical properties.

[0130] like Figures 8 to 11 It is known that after adding the light-absorbing material provided in this application to the filter film, the transmittance spectrum of the filter film shows a significant decrease in transmittance or a cutoff band at the position of the corresponding material absorption peak. This indicates that the filter film can effectively absorb near-infrared light in a specific wavelength range. When integrated into a display device, this filter film with selective absorption in the near-infrared region can effectively filter out near-infrared components in the backlight or ambient light, thereby reducing the interference of infrared light on visible light imaging and improving the color purity and contrast of the displayed image.

[0131] The above provides a detailed description of a light-absorbing material, its preparation method, and a display device provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A light-absorbing material, characterized in that, The light-absorbing material is selected from at least one of the structures shown in formula (1): (1)； Wherein, R is independently selected from hydrogen atoms or substituents having 1 to 6 carbon atoms; The light-absorbing material has a maximum absorption wavelength in the wavelength range of 600 nm to 1100 nm.

2. The light-absorbing material according to claim 1, characterized in that, The R is independently selected from alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 3 to 6 carbon atoms, alkenyl groups having 2 to 6 carbon atoms, alkynyl groups having 2 to 6 carbon atoms, aryl or heteroaryl groups having 6 cyclic atoms, alkylamino groups having 1 to 2 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, alkylthio groups having 1 to 6 carbon atoms, or cyano groups having 1 to 6 carbon atoms; at least one hydrogen atom on the alkyl group is not substituted or is substituted by a halogen atom.

3. The light-absorbing material according to claim 2, characterized in that, The R is independently selected from methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isopropyl, isobutyl, sec-butyl, tert-butyl, neopentyl, isopentyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 1,3-butadienyl, ethynyl, 1-propynyl, 2-propynyl, methylamino, ethylamino, dimethylamino, diethylamino, phenyl, alkoxy, ethoxy, propoxy, butoxy, methylthio, ethylthio, cyano, trifluoromethyl, trichloromethyl, or 2,2,2-trifluoroethyl.

4. The light-absorbing material according to claim 1, characterized in that, The R is selected from hydrogen atom, tert-butyl, n-butyl or n-hexyl, and different R are selected from the same group.

5. The light-absorbing material according to claim 1, characterized in that, The light-absorbing material has a maximum absorption wavelength in the wavelength range of 700 nm to 730 nm and in the range of 980 nm to 1020 nm.

6. A method for preparing a light-absorbing material, characterized in that, Includes the following steps: A carbazole diboronic acid ester with a substituent R, dibromothiophene, a palladium catalyst, a base, and a first solvent are mixed to form a mixed solution; wherein, R is independently selected from hydrogen atoms or substituents having 1 to 6 carbon atoms; The mixed solution was heated under the protection of an inert gas to obtain an intermediate. as well as The intermediate, oxidant, and second solvent are mixed and treated to obtain the light-absorbing material as described in any one of claims 1 to 5.

7. The preparation method according to claim 6, characterized in that, The palladium catalyst is selected from at least one of bis(triphenylphosphine)palladium dichloride, tetra(triphenylphosphine)palladium, tris(dibenzylideneacetone)palladium and 1,1'-bis(triphenylphosphine)ferrocenepalladium dichloride; And / or, the base is selected from at least one of potassium carbonate, potassium phosphate, cesium carbonate, potassium fluoride and cesium fluoride; And / or, the first solvent is selected from at least one of toluene, N,N-dimethylformamide, 1,4-dioxane and tetrahydrofuran; And / or, the oxidant is selected from at least one of manganese dioxide, lead dioxide and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone; And / or, the second solvent is selected from at least one of dichloromethane and chloroform.

8. The preparation method according to claim 6, characterized in that, The heating time for the mixed solution ranges from 24 to 48 hours, and the heating temperature is greater than or equal to the boiling point of the solvent.

9. A display device, characterized in that, It includes a display panel and a light-absorbing film disposed on at least one side or inside the display panel; the material of the light-absorbing film includes the light-absorbing material according to any one of claims 1 to 5 or the light-absorbing material prepared by the preparation method according to any one of claims 6 to 8.

10. The display device according to claim 9, characterized in that, In the filter film, the mass fraction of the light-absorbing material ranges from 0.3% to 3.0%.

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