A doped organic room-temperature phosphorescent material with high brightness and super-long lifetime, and a preparation method and application thereof

Abstract

This invention discloses a doped organic room-temperature phosphorescent material with both high brightness and ultra-long lifetime, its preparation method, and its application, relating to the field of organic room-temperature phosphorescent materials technology. The series of phosphorescent emitters DCMCy-1 and DCMCy-3 provided by this invention have novel molecular structures; an organic room-temperature phosphorescent material includes a phosphorescent emitter and a 5-methoxynaphthone triplet-state sensitizing matrix. Through molecular engineering, this invention introduces dicyanomethylene groups and intramolecular weak interactions into the phosphorescent emitter structure to enhance its rigidity and suppress non-radiative decay from within the molecule; by selecting a quasi-planar, special triplet-state photosensitive matrix, it enhances triplet energy transfer between the matrix and the phosphorescent emitter while suppressing non-radiative decay from outside the molecule, resulting in an organic room-temperature phosphorescent material with both ultra-long lifetime and high brightness, which is applied to a visible fluorescent / phosphorescent dual-anti-counterfeiting icon under an ambient light illuminance of 50 lux.

Description

Technical Field

[0001] This invention relates to the field of organic room temperature phosphorescent material synthesis technology, specifically to a doped organic room temperature phosphorescent material with both high brightness and ultra-long lifetime, its preparation method and application. Background Technology

[0002] In recent years, a large number of reports in the literature have highlighted the high phosphorus photon yield (PPT) Φ P or long phosphorescence lifetime ( τ P Energy-transfer organic room-temperature phosphorescent materials. (Nat. Commun. 2021, 3522; Angew. Chem. Int. Ed. 2023,e202315911; Nat. Commun. 2024, 3660; Adv. Mater. 2025, 2418042) However, according to the El-Sayed rule, τ P and Φ P These factors mutually constrain each other, resulting in very few examples of doped organic room-temperature phosphorescent materials achieving phosphorescence lifetimes and quantum yields exceeding 200 ms and 10% simultaneously (Angew. Chem. Int. Ed. 2020, 16054; J. Mater. Chem. C2021, 3391; Chem. Eng. J. 2022, 133530; J. Phys. Chem. Lett. 2023, 2187; Chem. Eng. J. 2024, 152492).

[0003] Based on the molecular engineering design principles of phosphorescent emitters proposed by Professor Shuai Zhigang et al., increasing the proportion of T1 excited states (π,π*) electronic configurations in the guest emitter will inhibit the T1→S0 transition, thereby extending the phosphorescence lifetime (Chem. 2016, 592; J. Am. Chem. Soc. 2019, 1010). Furthermore, by using weak intramolecular interactions and functional groups that reduce nonradiative transitions, while simultaneously strengthening the intermolecular interactions between the host and guest molecules, high quantum yield can be achieved while maintaining a long phosphorescence lifetime (Angew. Chem. Int. Ed. 2025, e202522260). Therefore, designing phosphorescent emitters and strongly interacting triplet photosensitive matrices based on molecular engineering and host-guest engineering principles is a key issue in constructing doped organic room-temperature phosphorescent materials with both high brightness and long phosphorescence lifetime. Summary of the Invention

[0004] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide a doped organic room temperature phosphorescent material with both high brightness and long phosphorescence lifetime and its preparation method, specifically providing a type of phosphorescent emitter containing a dicyanomethylenepyran structure and a matching triplet sensitizing matrix.

[0005] Because most phosphorescent materials are limited by their lifetime and phosphorescence yield, their afterglow can only be observed under near-dark or completely dark conditions. However, the organic room-temperature phosphorescent material provided by this invention combines high brightness with an ultra-long lifetime. Under normal indoor ambient lighting conditions (50 Lux), the material's significant afterglow after excitation can be directly observed with the naked eye without needing to block ambient light. Therefore, this invention also provides an application of this phosphorescent material in visible fluorescent / phosphorescent dual-layer anti-counterfeiting icons under 50 lux ambient light conditions. This improves the anti-counterfeiting effect of luminescent anti-counterfeiting icons while overcoming the limitation of phosphorescent anti-counterfeiting applications being difficult to implement under ambient light conditions.

[0006] The technical solution of the present invention is as follows: In a first aspect, the present invention provides a series of phosphorescent emitters, said phosphorescent emitters having, for example, DCMCy-1 One of the structures shown in DCMCy-3: .

[0007] Secondly, the present invention provides a method for preparing the phosphorescent emitter, comprising the following steps: Under protective gas conditions, N-methyl-2-methylthiobenzyl heterocyclic onion salt and 2,6-dimethyl-4H-4-pyranylmalonium dinitrile were used as raw materials, and the raw materials were reacted at low temperature in an organic solvent in the presence of an organic superbase. After the reaction was completed, water was added to the reaction mixture, and the product was extracted with dichloromethane, dried, and concentrated under reduced pressure to obtain a crude product. The crude product was then subjected to chromatography to obtain the phosphorescent emitter.

[0008] As a further preferred embodiment, the N-methyl-2-methylthiobenzohexacyclic salt is at least one of 3-methyl-2-methylmercaptobenzoxazole trifluoromethanesulfonate, 3-methyl-2-methylmercaptobenzothiazole perchlorate, and 1,3,3-trimethyl-2-(methylthio)-3H-indole trifluoromethanesulfonate.

[0009] As a further preferred embodiment, the organic superbase is at least one of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) or 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene.

[0010] As a further preferred embodiment, the molar ratio of the N-methyl-2-methylthiobenzohexacyclic onium salt, 2,6-dimethyl-4H-4-pyranylmalonium nitrile, and the organic superbase is 1:1 to 1.5:1 to 1.1.

[0011] As a further preferred embodiment, the temperature of the low-temperature reaction is -40 ℃ to -20 ℃, and the reaction time is 1 h to 3 h.

[0012] As a further preferred embodiment, the organic solvent is at least one selected from dichloromethane, 1,2-dichloroethane, tetrahydrofuran, acetonitrile, ethyl acetate, dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

[0013] Thirdly, the present invention provides a doped organic room-temperature phosphorescent material that combines high brightness and long phosphorescence lifetime. The doped organic room-temperature phosphorescent material comprises a triplet-state sensitizing matrix and a phosphorescent emitter. The triplet-state sensitizing matrix is ​​5-methoxynaphthone, and the phosphorescent emitter is the aforementioned DCMCy-1. At least one of DCMCy-3.

[0014] In this invention, the triplet sensitizing matrix must be 5-methoxynaphthone (5M-TL). Other aryl ketone triplet sensitizing matrices cannot achieve both high brightness and ultra-long lifetime room temperature phosphorescence.

[0015] As a further preferred embodiment, the molar ratio of the triplet sensitized matrix to the phosphorescent emitter is 1000:1 to 1000:5; when the ratio is less than 1000:1, the room temperature phosphorescence of the material is significantly darkened; when the ratio is greater than 1000:5, the phosphorescent emitter will aggregate, resulting in a decrease in phosphorescence intensity.

[0016] Fourthly, the present invention provides a method for preparing the doped organic room-temperature phosphorescent material with both high brightness and ultra-long lifetime, comprising the following steps: The triplet-state sensitized matrix and the phosphorescent emitter were dissolved in an organic solvent to obtain matrix mother liquor and phosphorescent emitter mother liquor, respectively. The phosphorescent emitter mother liquor and the matrix mother liquor were mixed evenly, concentrated and dried to obtain an amorphous doped room temperature phosphorescent material. The amorphous doped room temperature phosphorescent material is heated to the melting point of the triplet photosensitive matrix. After the sample melts, it is poured into a mold, cooled to room temperature, and demolded to obtain the doped organic room temperature phosphorescent material with both high brightness and ultra-long lifetime.

[0017] As a further preferred embodiment, the organic solvent is at least one selected from dichloromethane, chloroform, tetrahydrofuran, dioxane, ethyl acetate, acetonitrile, methanol, ethanol, and dimethylformamide.

[0018] Fifthly, the present invention provides the application of the phosphorescent material in the application of a visible fluorescent / phosphorescent dual anti-counterfeiting icon under an ambient light illuminance of 50 lux.

[0019] As a further preferred embodiment, the method of application includes the following steps: The anti-counterfeiting ink is obtained by mixing the phosphorescent material powder with the water-based adhesive in a certain proportion.

[0020] The anti-counterfeiting ink is applied to the surface of banknotes and other items using screen printing. After drying at room temperature for 24 hours, a dual anti-counterfeiting icon that is visible under an ambient light level of 50 lux can be obtained.

[0021] In a sixth aspect, the present invention provides a dual anti-counterfeiting ink that is visible under ambient light illuminance of 50 lux, comprising the doped organic room temperature phosphorescent material that has both high brightness and ultra-long lifespan, i.e., the anti-counterfeiting ink includes the phosphorescent material.

[0022] In a seventh aspect, the present invention provides a method for preparing a visible fluorescent / phosphorescent dual anti-counterfeiting ink under an ambient light illuminance of 50 lux, comprising the following steps: The phosphorescent material is ground to a particle size of 10-20 μm and then thoroughly mixed with an equal mass of polyvinyl alcohol aqueous solution to obtain the anti-counterfeiting ink; the polyvinyl alcohol aqueous solution has a solid content of 15-18% and a viscosity of 3.0-5.0 Pa. s.

[0023] Eighthly, the present invention provides a method for visual fluorescence / phosphorescence dual anti-counterfeiting detection under an ambient light illuminance of 50 lux, comprising the following steps: Under normal indoor lighting conditions with an ambient illuminance of 50 Lux, the anti-counterfeiting icon formed by the dual anti-counterfeiting ink will emit bright fluorescence when directly irradiated with a 365 nm ultraviolet lamp. After the ultraviolet lamp is turned off, without the need for light shielding, a significant afterglow can be observed in the anti-counterfeiting icon with the naked eye.

[0024] As a further preferred embodiment, if the anti-counterfeiting icon displays a fluorescent icon under ultraviolet light, and after the ultraviolet light is turned off, the anti-counterfeiting icon exhibits afterglow under normal indoor lighting conditions, i.e., an ambient illuminance of 50 Lux, then the product is genuine; if the anti-counterfeiting icon does not display a fluorescent icon or does not exhibit afterglow under normal indoor lighting conditions, i.e., an ambient illuminance of 50 Lux, after the ultraviolet light is turned off, then the product is counterfeit.

[0025] This invention has at least one of the following beneficial effects: This invention provides a novel pure π→π* transition phosphorescent emitter (DCMCy-1–DCMCy-3) with a simple molecular structure, which is easy to prepare and exhibits stable properties. Furthermore, this invention also provides a method for preparing a doped organic room-temperature phosphorescent material with both high brightness and ultra-long lifetime. This method utilizes molecular engineering and host-guest engineering to simultaneously suppress non-radiative decay from both the inside and outside of the phosphorescent emitter molecule, thereby obtaining a material with both high brightness and ultra-long lifetime. τ P With Gao Φ P This invention discloses an organic room-temperature phosphorescent material. The simultaneous presence of high brightness and ultra-long lifetime allows for the observation of noticeable afterglow emission with the naked eye under normal indoor lighting conditions with an illuminance of 50 Lux, whereas ordinary phosphorescent materials only exhibit afterglow emission under complete darkness. Data from the embodiments show that the doped organic room-temperature phosphorescent material provided by this invention achieves a lifetime of over 200 ms and a phosphorescent quantum yield of over 10%, with the DCMCy-1 / 5M-TL phosphorescent material exhibiting the best performance, exhibiting a room-temperature phosphorescent lifetime >1000 ms and a phosphorescent quantum yield >33%. Furthermore, this invention also provides an application for visible fluorescent / phosphorescent dual-layer anti-counterfeiting icons under an ambient light illuminance of 50 lux, effectively improving the anti-counterfeiting effect of luminescent anti-counterfeiting icons and overcoming the limitation that phosphorescent anti-counterfeiting applications are difficult to see with the naked eye under ambient light conditions. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 The fluorescence emission spectrum, phosphorescence emission spectrum, and phosphorescence quantum yield of DCMCy-1 / 5M-TL (1000:1) are shown. Figure 2 This is the phosphorescence lifetime diagram of DCMCy-1 / 5M-TL (1000:1); Figure 3 The fluorescence and afterglow image is of DCMCy-1 / 5M-TL (1000:1); Figure 4 The fluorescence emission spectrum, phosphorescence emission spectrum, and phosphorescence quantum yield of DCMCy-2 / 5M-TL (1000:3) are shown. Figure 5 This is the phosphorescence lifetime diagram of DCMCy-2 / 5M-TL (1000:3); Figure 6 The fluorescence and afterglow image is of DCMCy-2 / 5M-TL (1000:3); Figure 7 The fluorescence emission spectrum, phosphorescence emission spectrum, and phosphorescence quantum yield of DCMCy-3 / 5M-TL (1000:1) are shown. Figure 8 This is the phosphorescence lifetime diagram of DCMCy-3 / 5M-TL (1000:1); Figure 9 The fluorescence and afterglow image is of DCMCy-3 / 5M-TL (1000:1); Figure 10 These are fluorescence and afterglow photographs of three samples, DCMCy-1 / 5M-TL (1000:1), DCMCy-2 / 5M-TL (1000:3), and DCMCy-3 / 5M-TL (1000:1), under an ambient light intensity of 50 lux. Figure 11 This is the application of the anti-counterfeiting ink based on three different phosphorescent materials in Example 10 for visual fluorescence / phosphorescence dual anti-counterfeiting under an ambient light illuminance of 50 lux. Detailed Implementation

[0028] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0029] It should be noted that the preparation processes for the organic room-temperature phosphorescent materials in the examples are similar, the only difference being the doping ratio of the matrix and the phosphorescent emitter. The following examples use a 5-methoxynaphthoquinone (5M-TL) matrix as an example of the preparation method. The structural formulas of the phosphorescent emitter and the matrix used in this invention are shown below: The present invention will be further described in detail below with reference to specific embodiments, but the present invention is not limited to the following specific embodiments.

[0030] Example 1 The preparation of the phosphorescent emitter DCMCy-1 specifically includes the following steps: Under argon protection, 2,6-dimethyl-4 H DBU (178 μL, 1.20 mmol) was added dropwise to a dry dichloromethane solution (5 mL) of 4-pyranopropyl malononitrile (200 mg, 1.16 mmol) and the mixture was stirred at -25 °C for 5 min. Then, a dimethylformamide solution (0.5 mL) of 3-methyl-2-methylmercaptobenzoxazole trifluoromethanesulfonate (382 mg, 1.16 mmol) was slowly added dropwise. The reaction mixture was stirred at -25 °C for 1 h. After returning to room temperature, water (20 mL) was added. The aqueous phase was extracted with dichloromethane (15 mL × 3), and the combined organic phases were dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography (eluent: dichloromethane) to give a yellow solid DCMCy-1 (67 mg, 19% yield), melting point: 279 °C–280 °C.

[0031] The spectral characterization data of DCMCy-1 are as follows: ( Z )-2-(2-methyl-6-((3-methylbenzo[ d Oxazole-2(3) H )-Methylene)methyl)-4 H -pyran-4-yl)malononitrile (DCMCy-1). Z )-2-(2-Methyl-6-((3-methylbenzo[ d ]oxazol-2(3 H )-ylidene)methyl)-4 H -pyran-4- ylidene) malononitrile. 1 H NMR (400 MHz, DMSO- d 6): δ 7.46–7.37 (m, 2H), 7.32 (dd, J 1= J 2 = 7.6 Hz, 1H), 7.19 (dd, J 1= J 2= ​​7.6 Hz, 1H), 6.63(s, 1H), 6.37 (s, 1H), 5.22 (s, 1H), 3.50 (s, 3H), 2.35 (s, 3H) ppm; 13 C NMR (400 MHz, DMSO-) d 6):δ 163.0, 161.3, 159.1, 155.2, 145.8, 131.7, 125.0, 122.6,117.3 (×2), 109.5, 109.2, 103.8, 97.6, 68.0, 47.7, 29.5, 19.1 ppm; IR (KBr): v max 2972, 2920, 2200, 2176, 1645, 1619, 1532, 1491, 1442, 1356, 1311, 1266,1195, 1082, 899, 831, 738 cm -1 HRMS (ESI+): m / z calcd for C 18 H 13 N3O2Na [M+Na] + 326.0900; found 326.0896. Example 2 The preparation of the phosphorescent emitter DCMCy-2 specifically includes the following steps: Under argon protection, 2,6-dimethyl-4 H DBN (157 μL, 1.28 mmol) was added dropwise to a dry 1,2-dichloroethane solution (4 mL) of 4-pyranopropyl malononitrile (200 mg, 1.16 mmol) and the mixture was stirred at -40 °C for 5 min. Then, a dimethylformamide solution (0.5 mL) of 3-methyl-2-methylmercaptobenzothiazole perchlorate (410 mg, 1.39 mmol) was slowly added dropwise. The reaction mixture was stirred at -40 °C for 3 h, and after returning to room temperature, water (20 mL) was added. The aqueous phase was extracted with dichloromethane (15 mL × 3), and the combined organic phases were dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography (eluent: dichloromethane) to give a red solid DCMCy-2 (118 mg, 31% yield), melting point: 324 °C–325 °C.

[0032] The spectral characterization data of DCMCy-2 are as follows: ( Z )-2-(2-methyl-6-((3-methylbenzo[ d ]Thiazol-2(3 H )-methylene)-4 H -pyran-4-yl)malononitrile (DCMCy-2). Z)-2-(2-Methyl-6-((3-methylbenzo[ d ]thiazol-2(3 H )-ylidene)methyl)-4 H -pyran- 4-ylidene)malononitrile . 1 H NMR (400 MHz, DMSO- d 6): δ 7.81 (d, J = 7.4 Hz, 1H), 7.51–7.41 (m, 2H), 7.22 (dd, J 1= J 2= ​​7.4 Hz, 1H), 6.41 (s, 2H), 6.18 (s, 1H), 3.62 (s, 3H), 2.46 (s, 3H) ppm; 13 C NMR (400 MHz, DMSO- d 6): δ 162.4, 160.3, 155.2, 154.2, 140.6, 127.1, 124.5, 122.8, 122.0, 117.3 (×2),111.2, 104.0, 99.1, 83.4, 47.7, 32.4, 18.9 ppm; IR (KBr): v max 2922, 2853, 2195,2169, 1655, 1541, 1475, 1437, 1406, 1375, 1319, 1195, 1150, 1124, 925, 812,745, 563, 530, 501 cm -1 HRMS (ESI+): m / z calcd for C 18 H 13 N3OSNa [M+Na] + 342.0672; found 342.0670. Example 3 The preparation of the phosphorescent emitter DCMCy-3 specifically includes the following steps: Under argon protection, 2,6-dimethyl-4 HDBU (181 μL, 1.22 mmol) was added dropwise to a tetrahydrofuran solution (5 mL) of pyranyl malononitrile (200 mg, 1.16 mmol) and the mixture was stirred at -20 °C for 5 minutes. Then, 1,3,3-trimethyl-2-(methylthio)- ... H A solution of indole trifluoromethanesulfonate (453 mg, 1.28 mmol) in dimethylformamide (0.5 mL) was prepared. The reaction mixture was stirred continuously at -20 °C for 1 hour. After returning to room temperature, water (20 mL) was added. The aqueous phase was extracted with dichloromethane (15 mL × 3). The combined organic phases were dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography (eluent: dichloromethane) to give an orange-red solid DCMCy-3 (76 mg, 20%) with a melting point of 291 °C–292 °C.

[0033] The spectral characterization data of DCMCy-3 are as follows: ( E )-2-(2-methyl-6-((1,3,3-trimethylindole-2-ylidene)methyl)-4 H -pyran-4-yl)malononitrile (DCMCy-3). E )-2-(2-Methyl-6-((1,3,3-trimethylindolin-2-ylidene)methyl)-4 H -pyran-4-ylidene)malononitrile. 1 H NMR (400 MHz, DMSO- d 6): δ 7.35 (d, J = 7.5 Hz, 1H), 7.23 (dd, J 1= J 2= ​​7.5 Hz, 1H), 7.07–6.98 (m, 2H), 6.56 (s, 1H), 6.48 (s,1H), 5.67 (s, 1H), 3.31 (s, 3H) , 2.45 (s, 3H), 1.61 (s, 6H) ppm; 13 C NMR (400MHz, DMSO- d 6): δ166.6, 162.3, 161.4, 155.3, 142.8, 139.4, 127.7, 121.9, 121.6,116.8, 116.7, 108.2, 104.5, 102.1, 87.1, 49.4, 46.9, 29.9, 24.6 (×2), 19.0ppm; IR (KBr): v max 2965, 2924, 2851, 2197, 2178, 1662, 1581, 1536, 1477, 1333,1129, 1022, 928, 823, 802, 752 cm -1 HRMS (ESI+): m / z calcd for C 21 H 19 N3ONa [M+Na] + 352.3922; found 352.3917. Example 4 The preparation of a high-brightness, ultra-long-lasting organic room-temperature phosphorescent material (DCMCy-1 / 5M-TL (1000:1)) specifically includes the following steps: Step 1: Dissolve 1.0 mg of the phosphorescent emitter DCMCy-1 prepared in Example 1 in 3.3 mL of dichloromethane to prepare a solution with a concentration of 1×10⁻⁶. -3 The phosphorescent emitter stock solution of M; simultaneously, 5-methoxynaphthone (5M-TL, 588 mg) was dissolved in dichloromethane (5 mL) to obtain the matrix stock solution (6.6 × 10⁻⁶). -1 M); Step 2: Take 3.3 mL of the phosphorescent emitter mother liquor obtained in Step 1 and mix it evenly with 5 mL of the matrix mother liquor obtained in Step 1. Remove the solvent by vacuum evaporation and dry under vacuum to obtain a yellow amorphous high-brightness ultra-long organic room temperature phosphorescent material; Step 3: Heat the yellow amorphous organic room temperature phosphorescent material obtained in Step 2 to 95 °C. After the sample is completely melted, pour the sample into a mold. Slowly cool to room temperature and demold to obtain a high-brightness ultra-long organic room temperature phosphorescent material (DCMCy-1 / 5M-TL (1000:1)) with a similar crystal morphology.

[0034] Example 5 The preparation of a high-brightness, ultra-long-lasting organic room-temperature phosphorescent material (DCMCy-2 / 5M-TL(1000:3)) specifically includes the following steps: Step 1: Dissolve the phosphorescent emitter DCMCy-2 (6.0 mg) prepared in Example 2 in dichloromethane (6.3 mL) to prepare a solution with a concentration of 3 × 10⁻⁶ mg / mL. -3 The phosphorescent emitter stock solution of M; simultaneously, 5-methoxynaphthol (5M-TL, 580 mg) was dissolved in dichloromethane (5 mL) to obtain the matrix stock solution (6.6 × 10⁻⁶). -1 M); Step 2: Take 3.3 mL of the phosphorescent emitter mother liquor obtained in Step 1 and mix it evenly with 5 mL of the matrix mother liquor obtained in Step 1. Remove the solvent by vacuum evaporation and dry under vacuum to obtain a yellow amorphous high-brightness ultra-long organic room temperature phosphorescent material; Step 3: Heat the yellow amorphous organic room temperature phosphorescent material obtained in Step 2 to 95 °C. After the sample is completely melted, pour the sample into a mold. Slowly cool to room temperature and demold to obtain a high-brightness ultra-long organic room temperature phosphorescent material (DCMCy-2 / 5M-TL(1000:3)) with a similar crystal morphology.

[0035] Example 6 The preparation of a high-brightness, ultra-long-lasting organic room-temperature phosphorescent material (DCMCy-3 / 5M-TL (1000:1)) specifically includes the following steps: Step 1: Dissolve the phosphorescent emitter DCMCy-3 (2.0 mg) prepared in Example 3 in dichloromethane (6.1 mL) to prepare a concentration of 1 × 10⁻⁶ mg / mL. -3 The phosphorescent emitter stock solution of M; simultaneously, 5-methoxynaphthol (5M-TL, 580 mg) was dissolved in dichloromethane (5 mL) to obtain the matrix stock solution (6.6 × 10⁻⁶). -1 M); Step 2: Take 3.3 mL of the phosphorescent emitter mother liquor obtained in Step 1 and mix it evenly with the matrix mother liquor obtained in Step 1 (5 mL). Remove the solvent under reduced pressure and dry under vacuum to obtain a yellow amorphous high-brightness ultra-long organic room temperature phosphorescent material. Step 3: Heat the yellow amorphous organic room temperature phosphorescent material obtained in Step 2 to 95 °C. After the sample is completely melted, pour the sample into a mold. Slowly cool to room temperature and demold to obtain a high-brightness ultra-long organic room temperature phosphorescent material (DCMCy-3 / 5M-TL (1000:1)) with a similar crystal morphology.

[0036] Example 7 Fluorescence / phosphorescence property testing: The performance of the three high-brightness, ultra-long organic room-temperature phosphorescent materials (DCMCy-1 / 5M-TL (1000:1), (DCMCy-2 / 5M-TL (1000:3)), and (DCMCy-3 / 5M-TL (1000:1)) prepared in Examples 4–6 was tested, and the specific process is as follows: The sample (10 mg) was placed in a quartz sample cell, and the fluorescence emission spectrum and phosphorescence emission spectrum of the sample were measured using a luminescence spectrometer (delay time 5 ms). The luminescence quantum yield of the sample was measured using an integrating sphere (excitation wavelength 350 nm). The phosphorescence quantum yield could be calculated based on the ratio of fluorescence to phosphorescence in the sample fluorescence spectrum.

[0037] The result is as follows Figures 1-9 As shown; Figure 1 The following are the fluorescence and phosphorescence emission spectra of DCMCy-1 / 5M-TL (1000:1), and are derived from... Figure 1 It can be seen that the material Φ P =33.1%.

[0038] Figure 2 The figure shows the phosphorescence lifetime of DCMCy-1 / 5M-TL (1000:1), and is derived from... Figure 2 It can be seen that the fluorescence lifetime of this material is... τ P = 1183 ms.

[0039] Figure 3 The image shown is a fluorescence and afterglow photograph of DCMCy-1 / 5M-TL (1000:1), and is composed of... Figure 3 It can be seen that when excited by a 365 nm ultraviolet lamp, the yellow-green afterglow emitted by the sample lasted for 15 seconds after the light source was turned off.

[0040] Figure 4 The following are the fluorescence and phosphorescence emission spectra of DCMCy-2 / 5M-TL (1000:3), and the results are shown by... Figure 4 It can be seen that the material Φ P =29.5%.

[0041] Figure 5 The figure shows the phosphorescence lifetime of DCMCy-2 / 5M-TL (1000:3), and is derived from... Figure 5 It can be seen that the fluorescence lifetime of this material is... τ P = 231 ms.

[0042] Figure 6 The image shown is a fluorescence and afterglow photograph of DCMCy-2 / 5M-TL (1000:3), and is composed of...Figure 6 It can be seen that when excited by a 365 nm ultraviolet lamp, the yellow-green afterglow emitted by the sample lasted for 3 seconds after the light source was turned off.

[0043] Figure 7 The following are the fluorescence and phosphorescence emission spectra of DCMCy-3 / 5M-TL (1000:1), and the results are shown by... Figure 7 It can be seen that the material Φ P =10.7%.

[0044] Figure 8 The figure shows the phosphorescence lifetime of DCMCy-3 / 5M-TL (1000:1), and is derived from... Figure 8 It can be seen that the fluorescence lifetime of this material is... τ P = 833 ms.

[0045] Figure 9 The image shown is a fluorescence and afterglow photograph of DCMCy-3 / 5M-TL (1000:1), and is composed of... Figure 9 It can be seen that when excited by a 365 nm ultraviolet lamp, the yellow-green afterglow emitted by the sample after the light source is turned off can last for up to 11 seconds.

[0046] Example 8 The fluorescence and afterglow of the samples under ambient light conditions were tested using the following method: The high-brightness ultralong phosphorescent material samples (DCMCy-1 / 5M-TL (1000:1), DCMCy-2 / 5M-TL (1000:3), DCMCy-3 / 5M-TL (1000:1)) prepared in Examples 4–6 were placed under an ambient light intensity of 50 lux, and the fluorescence emission of the samples under 365 nm ultraviolet light irradiation and the phosphorescence emission after the ultraviolet light was turned off were recorded with a camera.

[0047] The results are as follows Figure 10 As shown, under ultraviolet light, the three samples exhibit bright fluorescence of different colors; after the ultraviolet light is turned off, significant afterglow of different colors is visible under an ambient illuminance of 50 lux. Under an ambient illuminance of 50 lux, the afterglow time of DCMCy-1 / 5M-TL (1000:1) is 5 seconds, that of DCMCy-2 / 5M-TL (1000:3) is 2 seconds, and that of DCMCy-3 / 5M-TL (1000:1) is 5 seconds.

[0048] Example 9 The preparation method of a visible fluorescent / phosphorescent dual anti-counterfeiting ink under an ambient light illuminance of 50 lux includes the following steps: Example 4 The phosphorescent materials prepared in Example 6 were ground to a particle size of 10 mm. 20 μm. Each phosphorescent material powder (100 mg) was separately mixed with an equal volume of polyvinyl alcohol aqueous solution (solid content = 16%, viscosity = 3.8 Pa). Mix 100 mg of ink evenly to obtain three different anti-counterfeiting inks.

[0049] Example 10 The application of visual fluorescent / phosphorescent dual anti-counterfeiting under ambient light conditions of 50 lux is as follows: Using a printing plate with a four-leaf clover design and the number 100, pour the three types of anti-counterfeiting inks prepared in Example 9 into the blank areas of the printing plate, and apply the inks onto the practice banknotes using a scraper. Remove the printing plate and allow it to dry at room temperature for 24 hours.

[0050] During the anti-counterfeiting detection process, under normal indoor lighting conditions with an illuminance of 50 Lux, the anti-counterfeiting icon is illuminated with a 365 nm ultraviolet lamp. For example... Figure 11 As shown, under ultraviolet light, the anti-counterfeiting icon displays a distinct fluorescent pattern (first layer of anti-counterfeiting); when the ultraviolet light is turned off, without blocking visible light, the phosphorescent anti-counterfeiting icon with a distinctly different color and a significant afterglow can be observed with the naked eye, with the overall duration reaching 5 seconds (second layer of dynamic anti-counterfeiting).

[0051] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A phosphorescent emitter, characterized in that, The phosphorescent emitter has properties such as DCMCy-1 One of the structures shown in DCMCy-3: 。 2. The method for preparing the phosphorescent emitter according to claim 1, characterized in that, Includes the following steps: Under protective gas conditions, N-methyl-2-methylthiobenzyl heterocyclic onion salt and 2,6-dimethyl-4H-4-pyranylmalonium dinitrile were used as raw materials, and the raw materials were reacted at low temperature in an organic solvent in the presence of an organic superbase. After the reaction was completed, water was added to the reaction mixture, and the product was extracted with dichloromethane, dried, and concentrated under reduced pressure to obtain a crude product. The crude product was then subjected to chromatography to obtain the phosphorescent emitter.

3. The preparation method according to claim 2, characterized in that, The N-methyl-2-methylthiobenzohexacyclic salt is at least one of 3-methyl-2-methylmercaptobenzoxazole trifluoromethanesulfonate, 3-methyl-2-methylmercaptobenzothiazole perchlorate, and 1,3,3-trimethyl-2-(methylthio)-3H-indole trifluoromethanesulfonate; The organic superbase is at least one of 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene or 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene; The molar ratio of the N-methyl-2-methylthiobenzohexacyclic onium salt, 2,6-dimethyl-4H-4-pyranylmalonium nitrile, and the organic superbase is 1:1~1.5:1~1.1; The temperature of the low-temperature reaction is -40 ℃ to -20 ℃, and the reaction time is 1 h to 3 h. The organic solvent is at least one selected from dichloromethane, 1,2-dichloroethane, tetrahydrofuran, acetonitrile, ethyl acetate, dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

4. A doped organic room-temperature phosphorescent material possessing both high brightness and ultra-long lifetime, characterized in that, The phosphorescent material comprises a triplet-sensitized matrix and a phosphorescent emitter, wherein the triplet-sensitized matrix is ​​5-methoxynaphthone, and the phosphorescent emitter is DCMCy-1 as described in claim 1. At least one of DCMCy-3.

5. The doped organic room-temperature phosphorescent material with both high brightness and ultra-long lifetime according to claim 4, characterized in that, The molar ratio of the triplet sensitizing matrix to the phosphorescent emitter is 1000:1 to 1000:

5.

6. The method for preparing the doped organic room-temperature phosphorescent material with both high brightness and ultra-long lifetime as described in any one of claims 4-5, characterized in that, Includes the following steps: The triplet photosensitive matrix and the phosphorescent emitter were dissolved in an organic solvent to obtain matrix mother liquor and phosphorescent emitter mother liquor, respectively. The phosphorescent emitter mother liquor and the matrix mother liquor were mixed evenly, concentrated and dried to obtain an amorphous doped organic room temperature phosphorescent material. The amorphous doped organic room temperature phosphorescent material is heated to the melting point of the triplet photosensitive matrix. After the sample melts, it is poured into a mold, cooled to room temperature, and demolded to obtain the doped organic room temperature phosphorescent material with both high brightness and ultra-long lifetime.

7. The application of the doped organic room-temperature phosphorescent material with high brightness and ultra-long lifetime as described in any one of claims 4-5 in the application of a dual anti-counterfeiting icon with visible fluorescence / phosphorescence under an ambient light illuminance of 50 lux.

8. A dual anti-counterfeiting ink with visible fluorescence / phosphorescence under an ambient light level of 50 lux, characterized in that, Including the doped organic room-temperature phosphorescent material with both high brightness and ultra-long lifetime as described in any one of claims 4-5.

9. A method for preparing the dual anti-counterfeiting ink according to claim 8, characterized in that, Includes the following steps: The doped organic room temperature phosphorescent material with both high brightness and ultra-long lifespan is ground to a particle size of 10~20 μm and then thoroughly mixed with an equal mass of polyvinyl alcohol aqueous solution to obtain the dual anti-counterfeiting ink. The polyvinyl alcohol aqueous solution has a solid content of 15-18% and a viscosity of 3.0-5.0 Pa. s.

10. A method for detecting dual anti-counterfeiting features using visible fluorescence / phosphorescence under an ambient light intensity of 50 lux, characterized in that... Includes the following steps: Under normal indoor lighting conditions with an ambient illuminance of 50 lux, the anti-counterfeiting icon formed by the dual anti-counterfeiting ink described in claim 8 will emit bright fluorescence when directly irradiated with a 365 nm ultraviolet lamp. After the ultraviolet lamp is turned off, without the need for light shielding, a significant afterglow can be observed in the anti-counterfeiting icon with the naked eye.

Images