Fluorinated UV absorber compound, method for preparing same, and use thereof

Abstract

Disclosed is a fluorinated UV absorber compound which is a trimeric hydroxyphenyl benzotriazole derivative in which a plurality of hydroxyphenyl benzotriazole groups are bonded to one benzene substituted with fluorine. The fluorinated UV absorber compound according to the present invention exhibits improved solvent solubility, thermal stability and heat resistance at high temperatures, and excellent optical transparency. A transparent polyimide film prepared from the fluorinated UV absorber compound exhibits excellent ultraviolet absorption ability and light resistance.

Description

Fluorinated ultraviolet absorber compound, method of manufacturing the same, and use of the same

[0001] The present invention relates to a fluorinated ultraviolet absorber compound, a method for manufacturing the same, and uses thereof.

[0002]

[0003] Today, as industrialization continues, the problem of the ozone hole is becoming increasingly serious. The depletion of the ozone layer significantly increases the amount of ultraviolet (UV) radiation reaching the Earth's surface. Excessive UV radiation poses a serious threat to human health, while prolonged exposure causes discoloration, brittleness, and functional degradation in many materials. Ultraviolet radiation is high-energy light with short wavelengths found in sunlight and can be classified into UV-A, UV-B, and UV-C. UV-A covers the wavelength range of 315 nm to 400 nm, UV-B the range of 280 nm to 315 nm, and UV-C the range of 100 nm to 280 nm. While UV-B and UV-C are mostly absorbed by the ozone layer, UV-A reaches the Earth's surface and affects organisms, making UV-A blocking extremely important. UV absorbers can selectively absorb UV radiation and convert its energy into thermal energy or release it as harmless low-energy radiation.

[0004]

[0005] Currently, benzophenone, oxalanilide, bonzotriazole, and triazine aromatic compounds are primarily used as UV absorbers; however, most of these have various drawbacks, such as being low-molecular-weight, generating harmful VOCs (Vaporized Organic Compounds), being easily extracted, decomposing during production, or lacking heat resistance at high temperatures. Therefore, the development of new UV absorbers holds significant application prospects.

[0006]

[0007] With the advancement of science and technology, products incorporating various polymers often require high-temperature processes during manufacturing or are utilized in extreme environments, such as high-temperature environments, after production. For example, colorless polyimide polymers have recently been widely used in the production of flexible displays due to their advantages, such as high mechanical stability, transparency, and flexibility. It has been reported that during the manufacturing process of displays using such colorless polyimide, the materials are exposed to temperatures ranging from at least 100°C to as high as 300°C or higher.

[0008]

[0009] Meanwhile, transparent polyimides contain numerous aromatic groups within their structure, allowing them to absorb UV-A light. Consequently, exposure to UV-A can cause yellowing and a decrease in optical transmittance. While the use of UV absorbers can prevent yellowing and reduced optical transmittance, most currently commercialized UV absorbers have drawbacks, such as yellowing due to UV absorption, insufficient heat resistance for high-temperature or extreme environments, and low solvent solubility. Therefore, there is a need to develop novel UV absorbers with improved characteristics.

[0010]

[0011] In this regard, it is known that an ultraviolet absorber formed by using a phenolic benzotriazole derivative to create a twisted structure in which multiple benzotriazole groups are bonded to a single benzene molecule possesses excellent solvent solubility, heat resistance, and ultraviolet light absorption capacity (Patent Document 1).

[0012] While researching ultraviolet absorbers having superior solvent solubility, heat resistance, and optical transparency, the inventors developed a novel ultraviolet absorber with excellent chemical and optical properties, such as solvent solubility, heat resistance, and optical transparency, by preparing a fluorinated compound in which three hydroxyphenyl benzotriazoles are bonded around a fluorobenzene group as an ultraviolet absorber containing phenolic benzotriazoles, thereby completing the present invention.

[0013]

[0014] (Patent Document 1) Patent Document 1: Korean Published Patent No. 10-2022-0125824

[0015]

[0016] In one aspect of the present invention, the objective is to...

[0017] The invention provides a fluorinated ultraviolet absorber compound, a method for manufacturing the same, and uses thereof.

[0018] In addition, an object in another aspect of the present invention is

[0019] The present invention provides a composition for forming a polyimide film comprising a fluorinated compound having ultraviolet absorption ability.

[0020]

[0021] In order to achieve the above objective,

[0022] In one aspect of the present invention, a compound represented by the following chemical formula 1 is provided.

[0023] [Chemical Formula 1]

[0024]

[0025] In the above chemical formula 1, R 1 and R 2 Each is independently a C1-C10 alkyl group, and

[0026] Each X is either hydrogen or fluorine, but at least one of the three Xs is fluorine.

[0027]

[0028] In another aspect of the present invention, a method for preparing a compound represented by Formula 1 is provided, comprising the step of reacting a compound represented by Formula 2 with a compound represented by Formula 3.

[0029]

[0030]

[0031] In the above reaction equation, R 1 , R 2 , X follows the definition in Chemical Formula 1 above.

[0032]

[0033] In another aspect of the present invention,

[0034] A composition for absorbing ultraviolet rays comprising a compound represented by the above chemical formula 1 is provided.

[0035] In addition, in another aspect of the present invention,

[0036] A composition for forming a transparent polyimide film having ultraviolet absorption properties is provided, comprising a compound represented by the above chemical formula 1, a polyimide, and an organic solvent.

[0037] In addition, in another aspect of the present invention,

[0038] A step of preparing a polyimide solution by mixing a compound represented by Chemical Formula 1, a polyimide, and an organic solvent; and

[0039] A method for manufacturing a transparent polyimide film is provided, comprising the step of applying the above polyimide solution onto a substrate.

[0040]

[0041] The UV absorber resin composition comprising the fluorinated UV absorber compound and the fluorinated compound having UV absorption ability according to the present invention exhibits excellent chemical and optical properties, as the increased molecular weight of the compound can significantly improve heat resistance capable of withstanding high temperatures, optical transparency regarding yellowing that occurs upon UV exposure, and solvent solubility.

[0042]

[0043] FIG. 1a is a graph showing the results of UV-vis spectroscopy performed using the compounds of Comparative Example 1, Comparative Example 2, and Example 1 dissolved in methylene chloride (MC);

[0044] FIG. 1b is a graph showing the results of UV-vis spectroscopy performed using the compounds of Comparative Example 1, Comparative Example 2, and Example 1 dissolved in N-methyl-2-pyrrolidone;

[0045] FIG. 1c is a graph showing the results of UV-vis spectroscopy performed using the solid-state compounds of Comparative Example 1, Comparative Example 2, and Example 1;

[0046] FIG. 2a is an image of the dried compound of Comparative Example 1;

[0047] FIG. 2b is an image of the dried compound of Comparative Example 2;

[0048] FIG. 2c is an image of the dried compound of Example 1;

[0049] FIG. 3a is a graph according to temperature of thermogravimetric analysis (TGA) performed using the compounds of Comparative Example 1, Comparative Example 2, and Example 1;

[0050] FIG. 3b is a graph of time over which thermogravimetric analysis (TGA) was performed using the compound of Comparative Example 2;

[0051] FIG. 3c is a graph of time over which thermogravimetric analysis (TGA) was performed using the compound of Example 1;

[0052] FIG. 4a is a graph showing the results of UV-vis spectroscopy performed using a transparent polyimide film having the UV absorption characteristics of Comparative Example 2;

[0053] FIG. 4b is a graph showing the results of UV-vis spectroscopy performed using a transparent polyimide film having the UV absorption characteristics of Example 1;

[0054] Figure 5a is a graph showing the results of UV-vis spectroscopy performed after preparing a transparent polyimide film that does not contain a UV absorber and irradiating it with a xenon lamp for 0 to 100 hours.

[0055] Figure 5b is a graph showing the results of UV-vis spectroscopy performed after preparing a transparent polyimide film containing the UV absorber (0.5 wt%) of Comparative Example 2 and irradiating it with a xenon lamp for 0 to 100 hours.

[0056] Figure 5c is a graph showing the results of UV-vis spectroscopy performed after preparing a transparent polyimide film containing the UV absorber (0.5 wt%) of Example 1 and irradiating it with a xenon lamp for 0 to 100 hours.

[0057]

[0058] The present invention will be described in detail below.

[0059] Meanwhile, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, embodiments of the present invention are provided to more completely explain the present invention to those with average knowledge in the relevant technical field.

[0060] Furthermore, throughout the specification, the term "comprising" a component means that, unless specifically stated otherwise, it does not exclude other components but rather may include additional components.

[0061]

[0062] In one aspect of the present invention, a compound represented by the following chemical formula 1 is provided.

[0063] [Chemical Formula 1]

[0064]

[0065] In the above chemical formula 1, R 1 and R 2 Each is independently a C1-C10 alkyl group, and

[0066] Each X is either hydrogen or fluorine, but at least one of the three Xs is fluorine.

[0067]

[0068] As another embodiment, R 1 and R 2 Each is independently a C1-C10 alkyl group, and X is all fluorinated, and

[0069] As another embodiment, R 1 and R 2 is tert-butyl, and X is a compound in which all are substituted with fluorine.

[0070]

[0071] The compound according to the above chemical formula 1 can be used as a fluorinated ultraviolet absorber and may include a pair of proton donors and proton acceptors.

[0072] The above proton donor is R 1 and R 2 It is a hydroxyl group (-OH) located adjacent to it, and the proton acceptor may be one of the nitrogens located adjacent to the hydroxyl group (-OH).

[0073] The above compound may possess ESIPT (excited-state intramolecular proton transfer) properties by including a pair of the proton donor and the proton acceptor. Accordingly, when the compound releases energy generated after absorbing ultraviolet light, it may release the energy non-luminously. Therefore, the compound may not impair the optical properties of surrounding polymeric materials. In other words, by including hydroxyphenyl benzotriazole, the compound minimizes visible light absorption, thereby possessing advantages such as excellent durability and high solubility without impairing optical properties.

[0074]

[0075] The compound represented by the above chemical formula 1 can be manufactured by a manufacturing method comprising the step of reacting the compound of chemical formula 2 with the compound of chemical formula 3 as shown in the reaction scheme below.

[0076]

[0077]

[0078] The above reaction may be carried out in the presence of a palladium catalyst, and the palladium catalyst may be tetrakis(triphenylphosphine)palladium, but is not limited thereto. The above reaction may be carried out under reflux conditions using an organic solvent such as tetrahydrofuran or ethyl acetate. If necessary, the reaction may be carried out by mixing a small amount of water with the organic solvent, and the amount of water added may be 1 to 10 parts by volume per 100 parts by volume of the organic solvent.

[0079]

[0080] The compound of Chemical Formula 2 above can be prepared by reacting Chemical Formula 4 and Chemical Formula 5 below.

[0081]

[0082] In the above chemical formula 4, R 1 , R 2It follows the definition in Chemical Formula 1 above.

[0083]

[0084] The above reaction may be carried out according to known methods within the scope of the creative ability of a person skilled in the art, for example, using an organic solvent in the presence of a palladium catalyst. The palladium catalyst may include PdCl2(PPh3)2. The organic solvent may be a high-boiling point solvent such as 1,4-dioxane.

[0085] As an example of a compound represented by the above chemical formula 4, R 1 and R 2 Tinubin 327 substituted with a tert-butyl group can be used.

[0086] The compound represented by the above chemical formula 5 may be bis(pinacolato)diboron.

[0087] In addition, the step of reacting the above mixture can be performed at a temperature of 100°C to 140°C.

[0088] The compound according to Formula 1 of the present invention is useful as an ultraviolet absorber and is characterized by having heat resistance.

[0089] The above compound is a compound having a trimeric structure in which multiple hydroxyphenyl benzotriazole groups are bonded to a fluorine-substituted benzene side chain, and it can be resistant to heat due to the increase in molecular weight caused by the multiple hydroxyphenyl benzotriazole groups. That is, the above compound can have high heat resistance capable of withstanding high temperature environments and extreme environments.

[0090] Typically, as the molecular weight of a compound increases, its heat resistance increases, but its solubility decreases. However, a fluorinated ultraviolet absorber compound based on a trimeric hydroxyphenyl benzotriazole according to one embodiment of the present invention may have a structure in which a plurality of hydroxyphenyl benzotriazole groups are twisted around a benzene containing one or more fluorines, as shown in Formula 1. In addition, by further enhancing the twisting between the benzene and the linker connected to the benzene by the fluorine atom contained in the central benzene, the attractive forces between the compounds (e.g., van der Waals bonds, π-π interactions, etc.) are relatively weakened, thereby allowing for a relative increase in solubility compared to compounds having a flat structure.

[0091]

[0092] In other aspects of work,

[0093] A composition for absorbing ultraviolet rays comprising a compound represented by the above chemical formula 1 is provided.

[0094] In addition, the above ultraviolet absorption composition provides a composition for forming a transparent polyimide film having ultraviolet absorption properties, comprising a compound represented by the above chemical formula 1, a polyimide, and an organic solvent.

[0095] The composition for forming a transparent polyimide film having the above-mentioned ultraviolet absorption properties may include a polyimide in which a compound represented by the above-mentioned chemical formula 1 is dispersed in an amount of 0.45 to 5.4 weight%.

[0096] In addition, N-methyl-2-pyrrolidone may be used as an organic solvent for the composition for forming a transparent polyimide film having the above-mentioned ultraviolet absorption properties.

[0097]

[0098] In other aspects of work,

[0099] A step of preparing a polyimide solution by mixing a compound represented by Chemical Formula 1, a polyimide, and an organic solvent; and

[0100] A method for manufacturing a transparent polyimide film is provided, comprising the step of applying the above polyimide solution onto a substrate.

[0101]

[0102] In the step of preparing the above polyimide solution, a compound represented by Chemical Formula 1 is dissolved in an N-methyl-2-pyrrolidone organic solvent to include polyimide dissolved in an amount of 0.45 to 5.4 weight%.

[0103] The transparent polyimide film formed after applying the above polyimide solution onto a substrate may further include the steps of drying and heating. It is preferable that the heating be performed at a temperature of 250°C to 350°C for the polyimide film.

[0104]

[0105] The present invention will be explained in detail below through examples and experimental examples.

[0106] However, the following examples and experimental examples are for the purpose of explaining the present invention, and the content of the present invention is not limited by the following examples and experimental examples.

[0107]

[0108] <Example 1> Preparation of a Fluorinated Ultraviolet Absorber Compound

[0109] It was manufactured as shown in the reaction equation below.

[0110]

[0111]

[0112]

[0113] Step 1: Manufacture of HBT-pin

[0114] Tinuvin 327 (3.0 g, 8.3 mmol), a benzotriazole-based UV absorber, bis(triphenylphosphine)palladium(II) dichloride (0.61 g, 0.83 mmol), and 1,4-dioxane (50 mL) were added to a 3-neck round-bottom flask and stirred. Subsequently, bis(pinacolaito)diborone (2.13 g, 8.3 mmol) and potassium acetate (0.83 g, 8.3 mmol) were added to the mixture, maintained at 120°C for 24 hours, and then cooled to room temperature. The organic layer of the reaction mixture was extracted using dichloromethane and water. The collected organic layer was dried with magnesium sulfate and then concentrated using a rotary evaporator. The concentrated mixture was purified by column chromatography using a dichloromethane-n-hexane (1:1 v / v) mixed eluent to obtain a pale yellow powder intermediate compound (HBT-pin) (2.45 g, purification yield: 65.68%).

[0115] Step 2: Preparation of F-TPBT

[0116] 1,3,4-trifluoro-2,4,6-triiodo-benzene (0.41 g, 0.8 mmol), tetrakis(triphenylphosphine)palladium, and tetrahydrofuran (50 mL) were added to a 3-neck round-bottom flask and mixed. Subsequently, the intermediate compound prepared in Example 1 (1.44 g, 3.2 mmol), potassium carbonate (0.66 g, 4.8 mmol), and distilled water (5 mL) were added, and the mixture was refluxed for 24 hours and then cooled to room temperature. The organic layer of the reaction mixture was extracted using dichloromethane and distilled water. The collected organic layer was dried with magnesium sulfate and then concentrated using a rotary evaporator. The concentrated mixture was purified by column chromatography using a dichloromethane:petroleum ether (1:3 v / v) mixed eluent to obtain a bright yellow crystalline fluorinated ultraviolet absorber compound (F-TPBT) (0.5 g, purification yield: 57.47%).

[0117]

[0118] <Example 2> Preparation of a transparent polyimide film having ultraviolet absorption properties

[0119] The fluorinated UV absorber prepared in Example 1 above was dissolved in an N-methyl-2-pyrrolidone organic solvent, and then 10 wt% of polyimide was added to a fluorinated absorber / organic solvent solution of 0.5 wt% to 6.0 wt%. A polyimide film was prepared by coating the fluorinated UV absorber-polyimide solution onto a transparent substrate.

[0120] The above polyimide film was subjected to a preheat treatment process at 80°C for 1 minute, and then dried at 80°C for 24 hours. The dried polyimide film was subjected to an additional heat treatment process in a 300°C oven for 20 minutes to produce a transparent polyimide film with UV absorption properties having a thickness of 0.5 μm.

[0121]

[0122] <Comparative Example 1>

[0123] Tinubin 327 compound (purchased from Tokyo Chemical Industry) was used as Comparative Example 1.

[0124]

[0125] <Comparative Example 2>

[0126] A compound (TPBT) having the following chemical structure was prepared using non-fluorinated triiodobenzene, similar to Example 1.

[0127]

[0128]

[0129] <Experimental Example 1> Evaluation of Solvent Solubility of Compounds

[0130] The solvent solubility of the compounds prepared in Comparative Example 1, Comparative Example 2, and Example 1 was evaluated, and the results are shown in Table 1.

[0131]

[0132] Comparative Example 1 Comparative Example 2 Example 1 Solubility 1.1 wt% > 8 wt% > 6 wt%

[0133]

[0134] It can be confirmed that the solubility of the compound prepared in Example 1 above is more than 5 times higher than that of the compound in Comparative Example 1 above, and has a very excellent solubility similar to that of the compound prepared in Comparative Example 2 above.

[0135] In addition, structural optimization calculations using the Density Functional Theory of the Gaussian 16 program were performed to measure the twist angle of the hydroxyphenyl benzotriazole bonded to the central phenyl group of the compounds prepared in Comparative Example 1 and Example 1. As a result, it was confirmed that the compound of Comparative Example 1 had a twist angle of 35–36 degrees, and the compound of Example 1 had a twist angle of approximately 59–60 degrees. This increase in the twist angle confirms that, despite the increase in the molecular weight of the compounds, they possess excellent solvent solubility by reducing intermolecular interactions (pi-pi stacking).

[0136]

[0137] <Experimental Example 2> Analysis of Optical Properties and Optical Transparency Properties of Compounds

[0138] To evaluate the optical absorbance of the above compounds in the ultraviolet region, UV-vis spectroscopy was performed using the compounds prepared in Comparative Example 1, Comparative Example 2, and Example 1, respectively, in solutions (10-5 M concentration) and solid states dissolved in methylene chloride (MC) and N-methyl-2-pyrrolidone, and the results are shown in Figures 1a, 1b, and 1c.

[0139] As shown in Figures 1a, 1b, and 1c, it was confirmed that the compound prepared in Example 1 has an optical absorbance in the ultraviolet wavelength range almost identical to that of the low-molecular-weight compound of Comparative Example 1, despite the molecular weight being increased due to the hydroxyphenyl benzotriazole group.

[0140] As a result of comparing the absorption spectra of the compound prepared in Example 1 and the compound prepared in Comparative Example 2, it was confirmed that the compound prepared in Comparative Example 2 has maximum absorption capacity at a relatively long wavelength of 360 nm, whereas the compound prepared in Example 1 has maximum absorption capacity at a relatively short wavelength of 351 nm, and it was confirmed that the absorbance of the same type as that of Comparative Example 1, which has maximum absorption capacity at 347 nm, appears in almost the same wavelength region.

[0141]

[0142] In addition, the maximum absorption wavelength (λmax) and light absorption coefficient (ε) of the light absorption spectra of the compounds prepared in Comparative Example 1, Comparative Example 2, and Example 1 are shown in Table 2.

[0143]

[0144] Comparative Example 1 Comparative Example 2 Example 1 Maximum absorption wavelength (λ max )347360351 Light absorption coefficient (ε) 11,000 79,000 77,000

[0145]

[0146] It was confirmed that the compounds prepared in Comparative Example 1, Comparative Example 2 and Example 1 above best absorbed wavelengths in the ultraviolet region, with a maximum absorption wavelength (λmax) of 347 nm to 360 nm in the ultraviolet-visible spectrum.

[0147] It was confirmed that the compound prepared in Example 1 has an excellent light absorption capacity seven times higher than that of the compound in Comparative Example 1.

[0148] In addition, to evaluate the optical transparency of the compounds, dried images of the compounds prepared in Comparative Example 1, Comparative Example 2, and Example 1 were shown in FIG. 2a, FIG. 2b, and FIG. 2c, respectively.

[0149] As shown in FIGS. 2a, 2b, and 2c, it was confirmed that the compound prepared in Comparative Example 2 has a deep yellow color, whereas the compound prepared in Example 1 has a relatively light yellow, off-white color.

[0150] The above results show that the introduction of fluorine into the benzene ring located at the center of the compound prepared in Example 1 significantly improved the twisting between the hydroxyphenyl benzotriazole and the benzene ring, and as a result, the p-orbital overlap between the hydroxyphenyl benzotriazoles was reduced, which significantly reduced the long-wavelength absorption and resulted in excellent optical transparency.

[0151]

[0152] <Experimental Example 3> Analysis of Heat Resistance Characteristics of Compounds

[0153] To evaluate the heat resistance of the above compounds, thermogravimetric analysis (TGA) was performed using the compounds prepared in Comparative Example 1, Comparative Example 2, and Example 1, and the results are shown in Figs. 3a, 3b, 3c, and Table 3, respectively.

[0154]

[0155] Comparative Example 1 Comparative Example 2 Example 11 Wt% Loss Temperature 1833603545 Wt% Loss Temperature 22744142710 Wt% Loss Temperature 247461449

[0156]

[0157] As shown in FIGS. 3A, 3B, 3C and Table 3, it was confirmed that the compound of Comparative Example 1 suffered a 1 wt% loss at 183°C, whereas the compound prepared in Example 1 suffered a 1 wt% loss at 354°C. Additionally, after maintaining the temperature at 300°C for 40 minutes and then raising it to 600°C to observe the weight change of the compound, it was confirmed that it possessed high thermal stability and ultra-high heat resistance capable of withstanding high-temperature environments.

[0158]

[0159] <Experimental Example 4> Analysis of Optical Transparency and Light Resistance Characteristics of Transparent Polyimide Film

[0160] A UV-absorbing composition was prepared using the compounds prepared in Comparative Example 2 and Example 1 above, and in order to confirm the optical properties of a transparent polyimide film having UV-absorbing characteristics prepared with the UV-absorbing composition,

[0161] A UV-absorbing composition was prepared containing 0.5% to 4.5% by weight of the compounds prepared in Comparative Example 2 and Example 1, respectively, and UV-vis spectroscopy was performed using a transparent polyimide film having UV-absorbing properties prepared with the UV-absorbing composition, and the results are shown in FIGS. 4a and FIGS. 4b, respectively.

[0162] As shown in FIGS. 4a and 4b, the transparent polyimide film containing the compound prepared in Comparative Example 1 shows that as the amount of compound added increases, the absorption in the ultraviolet long wavelength to visible short wavelength region increases, and the visible light transmittance decreases significantly. On the other hand, the transparent polyimide film containing the compound prepared in Example 1 shows that even if the amount of compound added increases, the increase in absorption in the ultraviolet long wavelength to visible short wavelength region is relatively small, and therefore the decrease in visible light transmittance is not large, so it can be seen that the optical transparency of the transparent polyimide film containing the compound prepared in Example 1 is superior.

[0163]

[0164] In addition, to analyze the light resistance characteristics of a transparent polyimide film prepared using the above compound, a transparent polyimide film containing 0.5 wt% of the compound was prepared, and after irradiating it with a xenon lamp for a certain period of time, UV-vis spectroscopy was performed, and the results are shown in Figs. 5a, 5b, and 5c, respectively.

[0165] It was confirmed that the transmittance of a transparent imide film not containing a UV absorber compound decreased by 5.2% when comparing the transmittance in the visible light wavelength range (400 nm) before and after xenon lamp irradiation.

[0166] On the other hand, in the case of a transparent polyimide film prepared using the compound prepared in Example 1 above, when comparing the transmittance in the visible light wavelength range (400 nm) before and after xenon lamp irradiation, the transmittance decreased by only 0.6%, so no yellowing occurred and transparency was maintained.

[0167] From the above results, it can be seen that the transparent polyimide film prepared using the compound prepared in Example 1 has significantly improved light resistance to ultraviolet rays and optical transparency.

[0168] As such, the fluorinated ultraviolet absorber compound according to the present invention appears to be applicable to the fabrication of displays composed of polyimide-based devices, components, display devices, etc., in that it exhibits improved solvent solubility, excellent heat resistance capable of withstanding high-temperature environments, and minimizes visible light absorption as an ultraviolet absorber without impairing the optical transparency of transparent polyimide films.

Claims

1. Compound represented by the following chemical formula 1: [Chemical Formula 1] In the above chemical formula 1, R 1 and R 2 Each is independently a C1-C10 alkyl group, and Each X is independently hydrogen or fluorine, but at least one of the three Xs is fluorine.

2. In Paragraph 1, R 1 and R 2 Each is independently a C1-C10 alkyl group, and X is a compound that is entirely fluorine.

3. In Paragraph 1, R 1 and R 2 It is tert-butyl, and X is a compound that is entirely fluorine.

4. A method for preparing a compound represented by Chemical Formula 1, comprising the step of reacting a compound represented by Chemical Formula 2 with a compound represented by Chemical Formula 3. R 1 and R 2 Each is independently a C1-C10 alkyl group, and Each X is independently hydrogen or fluorine, but at least one of the three Xs is fluorine.

5. In Paragraph 4, A compound represented by Chemical Formula 2 is prepared by a method comprising the step of reacting a compound represented by Chemical Formula 4 with a compound represented by Chemical Formula 5, Manufacturing method.

6. A composition for absorbing ultraviolet rays comprising the compound of claim 1.

7. A composition for forming a transparent polyimide film having ultraviolet absorption properties comprising polyimide and an organic solvent.

8. In Paragraph 7, The above organic solvent is a composition for forming a polyimide film, comprising N-methyl-2-pyrrolidone.

9. A transparent polyimide film comprising a polyimide in which the compound of claim 1 is dispersed at a content of 0.45 to 5.4 weight%.

10. A step of preparing a polyimide solution by mixing the compound of claim 1, polyimide, and an organic solvent; and A method for manufacturing a transparent polyimide film comprising the step of applying the above polyimide solution onto a substrate.

11. A display device comprising the transparent polyimide film of claim 9.

Images