Color-adjustable organic long-afterglow material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of organic materials, and discloses a color-adjustable organic long-afterglow material as well as a preparation method and application thereof. The compounds in the formula (I) and the formula (II) are aromatic organic compounds containing heteroatoms N and can be used as object components of the organic long-afterglow material; the organic long-afterglow material is prepared by taking a substance containing melamine formaldehyde resin as a main component and taking compounds shown in a formula (I) and a formula (II) as guest molecules, and the afterglow color of the material can be regulated and controlled by accurately controlling the doping amount of the guest molecules; the color-adjustable organic long afterglow material is low in doping amount of guest molecules, long in afterglow luminescence life and good in long afterglow performance stability, and the life of the maximum emission peak of a delay spectrum can reach 100 ms or above; after being activated by ultraviolet light, the fluorescent powder can generate bright afterglow from orange red to yellow white or afterglow from orange red to green, and has great application potential in anti-counterfeiting, data encryption, functional ink, road marking and multi-color display.

Description

Technical Field

[0001] The present invention relates to the technical field of organic materials, and particularly to a color-tunable organic long afterglow material, a preparation method thereof, and an application thereof. Background Art

[0002] The characteristic that long afterglow materials can still emit light continuously after removing the excitation light source has special significance in fields such as identifying light signals. By delaying the reception of light signals, the influence of light signals from the excitation light source, impurities, etc. can be removed, thereby greatly improving the clarity and recognition of light signals. Therefore, such materials are widely used in fields such as sensors, optical imaging, displays, and biotherapy.

[0003] Most traditional long afterglow materials are mainly inorganic components. Although their performance is excellent, their preparation processes often require the assistance of relatively high temperature conditions, resulting in an increase in production costs. In addition, inorganic long afterglow materials contain metal elements such as rare earth metals or transition metals. These factors have restricted the further development and application of inorganic long afterglow materials.

[0004] In comparison, organic long afterglow materials are more convenient and less costly in synthesis and modification, and can also be made flexible, and the impact on the environment is relatively small. In addition to these characteristics, color-tunable long afterglow materials also have richer changes in afterglow color, making them have a broader application prospect in fields such as anti-counterfeiting and stimulus response.

[0005] Currently, the color tuning of organic long afterglow materials is mainly achieved through the following methods: (1) realizing a red shift of the emission wavelength by changing and modifying the conjugated structure of organic molecules to stabilize triplet excitons; (2) changing the excitation wavelength to excite different luminescent centers in the polymer matrix; (3) using organic molecules with delayed fluorescence emission to achieve temperature-dependent color tuning; (4) realizing concentration-dependent color tuning by controlling the aggregation degree of organic molecules through doping concentration. Among them, the concentration-dependent organic molecule color tuning strategy is more advantageous because it is simpler and more convenient, and different afterglow colors can be displayed by only changing the doping concentration of organic molecules in the polymer matrix, and has a wider application range. At the same time, the organic long afterglow materials prepared by this method also have the advantages of a wide color tuning range and simple preparation. However, since most of the molecules used in this method have a large planar conjugated structure, their color tuning is mostly carried out by changing the degree of conjugation, and the means are relatively single. Therefore, it is urgent to develop diverse and rich color tuning methods to promote the practical application of color-tunable organic long afterglow materials. Summary of the Invention

[0006] The present invention aims to solve at least one of the above-mentioned technical problems in the prior art. To this end, one of the objectives of the present invention is to provide the use of the compounds of formula (Ⅰ) and formula (Ⅱ) in organic long-afterglow materials.

[0007] Another objective of the present invention is to provide a color-tunable organic long-afterglow material.

[0008] A third objective of the present invention is to provide a preparation method for this color-tunable organic long-afterglow material.

[0009] A fourth objective of the present invention is to provide the application of this color-tunable organic long-afterglow material.

[0010] A fifth objective of the present invention is to provide an anti-counterfeiting material.

[0011] To achieve the above objectives, the technical solutions adopted by the present invention are as follows:

[0012] The first aspect of the present invention provides the use of the compounds of formula (Ⅰ) and formula (Ⅱ) in organic long-afterglow materials. The structural formulas of the compounds of formula (Ⅰ) and formula (Ⅱ) are shown as follows:

[0013]

[0014] The second aspect of the present invention provides a color-tunable organic long-afterglow material, which includes a main component and a guest molecule doped in the main component; the guest molecule includes at least one of the compounds of formula (Ⅰ) and formula (Ⅱ) described in the first aspect of the present invention.

[0015] In some embodiments of the present invention, the main component includes melamine formaldehyde resin.

[0016] In some embodiments of the present invention, the doping amount of the guest molecule in the color-tunable organic long-afterglow material is 0.000005wt%-0.05wt%.

[0017] In some embodiments of the present invention, the color-tunable organic long-afterglow material is polymer powder.

[0018] In some embodiments of the present invention, the color-tunable organic long-afterglow material includes the following preparation raw materials: a guest molecule solution and a melamine formaldehyde resin prepolymer solution.

[0019] In some embodiments of the present invention, the concentration of the guest molecule solution is 1-4mg / mL.

[0020] In some specific embodiments of the present invention, the concentration of the guest molecule solution is 1-2mg / mL.

[0021] In some embodiments of the present invention, the solvent of the guest molecule solution includes at least one of methanol, ethanol, acetone, dimethyl sulfoxide, N,N-dimethylformamide, tetrahydrofuran, and acetonitrile.

[0022] In some specific embodiments of the present invention, the solvent of the guest molecule solution is tetrahydrofuran.

[0023] In some embodiments of the present invention, the pH value of the melamine formaldehyde resin prepolymer solution is 8-9.

[0024] In some embodiments of the present invention, the pH value of the melamine formaldehyde resin prepolymer solution is adjusted by adding at least one of amine, alkali metal hydroxide, and alkali metal carbonate.

[0025] In some specific embodiments of the present invention, the pH value of the melamine formaldehyde resin prepolymer solution is adjusted by adding at least one of diethylamine, triethylamine, triethanolamine, sodium hydroxide, potassium hydroxide, and sodium carbonate.

[0026] In some embodiments of the present invention, the melamine formaldehyde resin prepolymer solution is prepared by heating and reacting melamine with an aqueous formaldehyde solution.

[0027] In some embodiments of the present invention, the concentration of the aqueous formaldehyde solution is 35wt%-40wt%.

[0028] In some embodiments of the present invention, the solid-liquid ratio of melamine to the aqueous formaldehyde solution is 1g:(0.8-1.2)mL.

[0029] In some embodiments of the present invention, the temperature of the heating reaction is 80-100°C, and the time is 90-100 min.

[0030] In some embodiments of the present invention, the liquid-solid ratio of the guest molecule solution to the melamine formaldehyde resin prepolymer solution is (0.05-0.000005)mL:1g.

[0031] The inventive concept of the present invention is:

[0032] Using aromatic organic compounds of formula (I) or formula (II) doped with heteroatom N as guest molecules, doped into the host component in extremely low content, and by precisely controlling the aggregation state (single molecule, dimer, polymer) of the molecules in the matrix, full-color gamut luminescence regulation is achieved. Specifically: at extremely low concentrations, single molecules serve as the luminescence centers. As the concentration increases, dimers are gradually formed through intermolecular interactions to achieve red-shift color adjustment. When the concentration further increases, polymers become the main luminescence centers, and the emission is extended to the near-infrared region by virtue of rich intermolecular interactions and conjugated enhanced luminescence; by dynamically adjusting the proportion of the aggregation state and suppressing the concentration quenching effect, the limitations of traditional conjugated regulation are broken through, and the entire visible light band can be covered only by fine-tuning the concentration, providing an efficient and reversible solution for applications such as multicolor display and dynamic anti-counterfeiting.

[0033] The third aspect of the present invention provides a preparation method of the color-tunable organic long afterglow material described in the second aspect of the present invention, including the following steps:

[0034] S1. Mix and react a guest molecule solution and a melamine formaldehyde resin prepolymer solution to obtain a polymer solution;

[0035] S2. Coat the polymer solution on a carrier and dry it to obtain the color-tunable organic long afterglow material.

[0036] In some embodiments of the present invention, the mixing reaction time is 20 - 40 min.

[0037] In some specific embodiments of the present invention, the mixing reaction time is 25 - 35 min.

[0038] In some embodiments of the present invention, the mixing reaction process is assisted by ultrasonic waves.

[0039] In some embodiments of the present invention, the drying temperature is 150 - 170 °C and the time is 20 - 30 min.

[0040] In some specific embodiments of the present invention, the drying temperature is 155 - 165 °C and the time is 20 - 25 min.

[0041] In some embodiments of the present invention, after drying, it further includes the steps of cooling and grinding.

[0042] The fourth aspect of the present invention provides the application of the color-tunable organic long afterglow material described in the second aspect of the present invention in anti-counterfeiting, data encryption, functional inks, road signs, and multicolor displays.

[0043] The fifth aspect of the present invention provides an anti-counterfeiting material, including the color-tunable organic long afterglow material described in the second aspect of the present invention.

[0044] In some embodiments of the present invention, the anti-counterfeiting material further includes a polymer; the mass ratio of the color-tunable organic long-afterglow material to the polymer is (0.005 - 0.01):100.

[0045] In some embodiments of the present invention, when the color-tunable organic long-afterglow material in the anti-counterfeiting material uses the compound of formula (Ⅰ) as the guest molecule, the anti-counterfeiting material produces a bright orange-red to yellowish-white afterglow after being activated by an ultraviolet lamp.

[0046] In some embodiments of the present invention, when the color-tunable organic long-afterglow material in the anti-counterfeiting material uses the compound of formula (Ⅱ) as the guest molecule, the anti-counterfeiting material produces a bright orange-red to green afterglow after being activated by an ultraviolet lamp.

[0047] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0048] 1) The compounds of formula (Ⅰ) and formula (Ⅱ) are aromatic organic compounds containing heteroatom N, which can be applied to organic long-afterglow materials as the guest components of the organic long-afterglow materials; for the organic long-afterglow material prepared with a substance including melamine formaldehyde resin as the main component and the compounds of formula (Ⅰ) and formula (Ⅱ) as the guest molecules, by precisely controlling the doping amount of the guest molecules, the afterglow color of the material can be regulated.

[0049] 2) For the color-tunable organic long-afterglow material provided by the present invention, the doping amount of the guest molecules is low, the afterglow luminescence lifetime is long, the long-afterglow performance stability is good, and the lifetime of the maximum emission peak of the delayed spectrum can reach more than 100 ms.

[0050] 3) The preparation method of the color-tunable organic long-afterglow material provided by the present invention has simple steps and is suitable for industrial application.

[0051] 4) The color-tunable organic long-afterglow material provided by the present invention can produce a bright orange-red to yellowish-white afterglow, or an orange-red to green afterglow after being activated by ultraviolet light, and has great application potential in anti-counterfeiting, data encryption, functional inks, road signs, and multicolor displays. Description of the Drawings

[0052] Figure 1 1H NMR spectrum of the compound of formula (Ⅰ) in the example;

[0053] Figure 2 1H NMR spectrum of the compound of formula (Ⅱ) in the example;

[0054] Figure 3 Steady-state luminescence spectrum of the solid powders of the compounds of formula (Ⅰ) and formula (Ⅱ) in the example;

[0055] Figure 4 The luminescence decay curve of the solid powder of the compound of formula (I) in the examples;

[0056] Figure 5 The luminescence decay curve of the solid powder of the compound of formula (II) in the examples;

[0057] Figure 6 The steady-state luminescence and afterglow luminescence spectra of the color-tunable organic long-afterglow material in Example 1;

[0058] Figure 7 The afterglow luminescence spectra of the color-tunable organic long-afterglow materials in Examples 1-5;

[0059] Figure 8 The afterglow luminescence decay curves of the color-tunable organic long-afterglow materials in Examples 1-5;

[0060] Figure 9 The steady-state luminescence and afterglow luminescence spectra of the color-tunable organic long-afterglow material in Example 6;

[0061] Figure 10 The afterglow luminescence spectra of the color-tunable organic long-afterglow materials in Examples 6-10;

[0062] Figure 11 The afterglow luminescence decay curves of the color-tunable organic long-afterglow materials in Examples 6-10;

[0063] Figure 12 The ultraviolet lamp-excited afterglow photos of the color-tunable organic long-afterglow materials in Examples 1-5;

[0064] Figure 13 The ultraviolet lamp-excited afterglow photos of the color-tunable organic long-afterglow materials in Examples 6-10. Detailed implementation manners

[0065] The content of the present invention will be further described in detail through specific examples below. The raw materials, reagents or devices used in the examples can be obtained from conventional commercial channels or can be obtained by existing technical methods without special instructions. Unless otherwise specified, the test or measurement methods are all conventional methods in the art.

[0066] The compounds of formula (I) and formula (II) used in the following examples were all purchased from Bide Pharmatech. The product number of the compound of formula (I) is BD01850049, and the product number of the compound of formula (II) is BD01430772.

[0067] The nuclear magnetic resonance hydrogen spectrum of the pure solid powder (microcrystals) of the compounds of formula (I) and formula (II) was tested, Figure 1 The nuclear magnetic resonance hydrogen spectrum of the compound of formula (I) in the examples,Figure 2 1H NMR spectrum of the compound of formula (II) in the example. It can be seen from Figure 1 and Figure 2 that the compounds of formula (I) and formula (II) have the target structure and can be directly used for the preparation of the color-tunable organic long afterglow material in the example.

[0068] Example 1

[0069] In this example, a color-tunable organic long afterglow material was prepared as follows:

[0070] S11: Weigh 1 mg of the compound of formula (I) and dissolve it in 1 mL of tetrahydrofuran, and ultrasonically disperse it for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL.

[0071] S12: Add 5.224 g of melamine to 5.34 mL of 37 wt% aqueous formaldehyde solution, and then add triethanolamine to adjust the pH value of the solution to 8 - 9. Heat it at 90 °C for 100 min to form a clear melamine formaldehyde resin prepolymer solution.

[0072] S13: Add 0.05 mL of the guest molecule solution to 1 g of the melamine formaldehyde resin prepolymer solution, and ultrasonically mix and react for 30 min to obtain a polymer solution.

[0073] S21: Coat the polymer solution on a glass slide, bake it at 160 °C for 25 min, and scrape and grind it after cooling to obtain the color-tunable organic long afterglow material.

[0074] Example 2

[0075] In this example, a color-tunable organic long afterglow material was prepared as follows:

[0076] S11: Weigh 1 mg of the compound of formula (I) and dissolve it in 1 mL of tetrahydrofuran, and ultrasonically disperse it for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL.

[0077] S12: Add 5.224 g of melamine to 5.34 mL of 37 wt% aqueous formaldehyde solution, and then add triethanolamine to adjust the pH value of the solution to 8 - 9. Heat it at 90 °C for 100 min to form a clear melamine formaldehyde resin prepolymer solution.

[0078] S13: Add 0.005 mL of the guest molecule solution to 1 g of the melamine formaldehyde resin prepolymer solution, and ultrasonically mix and react for 30 min to obtain a polymer solution.

[0079] S21: Coat the polymer solution on a glass slide, bake it at 160 °C for 25 min, and scrape and grind it after cooling to obtain the color-tunable organic long afterglow material.

[0080] Example 3

[0081] In this example, a color-tunable organic long afterglow material is prepared as follows:

[0082] S11: Weigh 1 mg of the compound of formula (I) and dissolve it in 1 mL of tetrahydrofuran. Ultrasonically disperse it for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL.

[0083] S12: Add 5.224 g of melamine to 5.34 mL of 37 wt% aqueous formaldehyde solution, and then add triethanolamine to adjust the pH value of the solution to 8 - 9. Heat it at 90 °C for 100 min to form a clear melamine formaldehyde resin prepolymer solution.

[0084] S13: Add 0.0005 mL of the guest molecule solution to 1 g of the melamine formaldehyde resin prepolymer solution, and ultrasonically mix and react for 30 min to obtain a polymer solution.

[0085] S21: Coat the polymer solution on a glass slide, bake it at 160 °C for 25 min, and scrape and grind it after cooling to obtain the color-tunable organic long afterglow material.

[0086] Example 4

[0087] In this example, a color-tunable organic long afterglow material is prepared as follows:

[0088] S11: Weigh 1 mg of the compound of formula (I) and dissolve it in 1 mL of tetrahydrofuran. Ultrasonically disperse it for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL.

[0089] S12: Add 5.224 g of melamine to 5.34 mL of 37 wt% aqueous formaldehyde solution, and then add triethanolamine to adjust the pH value of the solution to 8 - 9. Heat it at 90 °C for 100 min to form a clear melamine formaldehyde resin prepolymer solution.

[0090] S13: Add 0.00005 mL of the guest molecule solution to 1 g of the melamine formaldehyde resin prepolymer solution, and ultrasonically mix and react for 30 min to obtain a polymer solution.

[0091] S21: Coat the polymer solution on a glass slide, bake it at 160 °C for 25 min, and scrape and grind it after cooling to obtain the color-tunable organic long afterglow material.

[0092] Example 5

[0093] In this example, a color-tunable organic long afterglow material is prepared as follows:

[0094] S11. Weigh 1 mg of the compound of formula (I) and dissolve it in 1 mL of tetrahydrofuran. Sonicate and disperse for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL.

[0095] S12. Add 5.224 g of melamine to 5.34 mL of 37 wt% aqueous formaldehyde solution. Then add triethanolamine to adjust the pH value of the solution to 8 - 9. Heat at 90 °C for 100 min to form a clear melamine - formaldehyde resin prepolymer solution.

[0096] S13. Add 0.000005 mL of the guest molecule solution to 1 g of the melamine - formaldehyde resin prepolymer solution. Sonicate and mix for 30 min to obtain a polymer solution.

[0097] S21. Coat the polymer solution on a glass slide, bake at 160 °C for 25 min, scrape off and grind after cooling to obtain a color - tunable organic long - persistent luminescence material.

[0098] Example 6

[0099] In this example, a color - tunable organic long - persistent luminescence material is prepared as follows:

[0100] S11. Weigh 1 mg of the compound of formula (II) and dissolve it in 1 mL of tetrahydrofuran. Sonicate and disperse for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL.

[0101] S12. Add 5.224 g of melamine to 5.34 mL of 37 wt% aqueous formaldehyde solution. Then add triethanolamine to adjust the pH value of the solution to 8 - 9. Heat at 90 °C for 100 min to form a clear melamine - formaldehyde resin prepolymer solution.

[0102] S13. Add 0.05 mL of the guest molecule solution to 1 g of the melamine - formaldehyde resin prepolymer solution. Sonicate and mix for 30 min to obtain a polymer solution.

[0103] S21. Coat the polymer solution on a glass slide, bake at 160 °C for 25 min, scrape off and grind after cooling to obtain a color - tunable organic long - persistent luminescence material.

[0104] Example 7

[0105] In this example, a color - tunable organic long - persistent luminescence material is prepared as follows:

[0106] S11. Weigh 1 mg of the compound of formula (II) and dissolve it in 1 mL of tetrahydrofuran. Sonicate and disperse for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL.

[0107] S12. Add 5.224 g of melamine into 5.34 mL of 37 wt% formaldehyde aqueous solution, then add triethanolamine to adjust the pH value of the solution to 8 - 9, and heat at 90 °C for 100 min to form a clear melamine - formaldehyde resin prepolymer solution;

[0108] S13. Add 0.005 mL of the guest molecule solution into 1 g of the melamine - formaldehyde resin prepolymer solution, and carry out ultrasonic mixing reaction for 30 min to obtain a polymer solution;

[0109] S21. Coat the polymer solution on a glass slide, bake at 160 °C for 25 min, and scrape and grind after cooling to obtain a color - tunable organic long - persistent luminescence material.

[0110] Example 8

[0111] This example prepares a color - tunable organic long - persistent luminescence material, and the steps are as follows:

[0112] S11. Weigh 1 mg of the compound of formula (II) and dissolve it in 1 mL of tetrahydrofuran, and carry out ultrasonic dispersion for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL;

[0113] S12. Add 5.224 g of melamine into 5.34 mL of 37 wt% formaldehyde aqueous solution, then add triethanolamine to adjust the pH value of the solution to 8 - 9, and heat at 90 °C for 100 min to form a clear melamine - formaldehyde resin prepolymer solution;

[0114] S13. Add 0.0005 mL of the guest molecule solution into 1 g of the melamine - formaldehyde resin prepolymer solution, and carry out ultrasonic mixing reaction for 30 min to obtain a polymer solution;

[0115] S21. Coat the polymer solution on a glass slide, bake at 160 °C for 25 min, and scrape and grind after cooling to obtain a color - tunable organic long - persistent luminescence material.

[0116] Example 9

[0117] This example prepares a color - tunable organic long - persistent luminescence material, and the steps are as follows:

[0118] S11. Weigh 1 mg of the compound of formula (II) and dissolve it in 1 mL of tetrahydrofuran, and carry out ultrasonic dispersion for 30 min to prepare a guest molecule solution with a concentration of 1 mg / mL;

[0119] S12. Add 5.224 g of melamine into 5.34 mL of 37 wt% formaldehyde aqueous solution, then add triethanolamine to adjust the pH value of the solution to 8 - 9, and heat at 90 °C for 100 min to form a clear melamine - formaldehyde resin prepolymer solution;

[0120] S13. Add 0.00005 mL of the guest molecule solution to 1 g of the melamine formaldehyde resin prepolymer solution, and ultrasonically mix and react for 30 min to obtain a polymer solution;

[0121] S21. Coat the polymer solution on a glass slide, bake it at 160 °C for 25 min, scrape it off and grind it after cooling to obtain a color-tunable organic long-afterglow material.

[0122] Example 10

[0123] This example prepares a color-tunable organic long-afterglow material, and the steps are as follows:

[0124] S11. Weigh 1 mg of the compound of formula (II) and dissolve it in 1 mL of tetrahydrofuran, ultrasonically disperse it for 30 min, and prepare a guest molecule solution with a concentration of 1 mg / mL;

[0125] S12. Add 5.224 g of melamine to 5.34 mL of 37 wt% aqueous formaldehyde solution, then add triethanolamine to adjust the pH value of the solution to 8 - 9, and heat it at 90 °C for 100 min to form a clear melamine formaldehyde resin prepolymer solution;

[0126] S13. Add 0.000005 mL of the guest molecule solution to 1 g of the melamine formaldehyde resin prepolymer solution, and ultrasonically mix and react for 30 min to obtain a polymer solution;

[0127] S21. Coat the polymer solution on a glass slide, bake it at 160 °C for 25 min, scrape it off and grind it after cooling to obtain a color-tunable organic long-afterglow material.

[0128] Performance test

[0129] Optical performance tests were carried out on the compounds of formula (I) and formula (II) used in the examples, and the color-tunable organic long-afterglow materials prepared in Examples 1 - 10. All tests were carried out on an Edinburgh FLS980 steady-state and transient fluorescence spectrometer with an integrating sphere:

[0130] Figure 3 is the steady-state luminescence spectrum of the solid powder of the compounds of formula (I) and formula (II) in the examples. As can be seen from Figure 3 , after being excited by ultraviolet light, the solid powders of the compounds of formula (I) and formula (II) did not produce long-afterglow luminescence, and both of them only had relatively high luminescence intensities in the wavelength range of 400 - 500 nm, that is, the compounds of formula (I) and formula (II) only emitted instantaneous fluorescence and did not have afterglow properties themselves.

[0131] Figure 4 is the luminescence decay curve of the solid powder of the compound of formula (I) in the example. As can be seen from Figure 4It can be seen that the duration of luminescence of the solid powder of the compound of formula (I) after being excited by ultraviolet light is short, and the fitting lifetime value is 2.3 ns, that is, the solid powder of the compound of formula (I) itself has no afterglow property and the luminescence intensity decays rapidly.

[0132] Figure 5 It is the luminescence decay curve diagram of the solid powder of the compound of formula (II) in the example. From Figure 5 It can be seen that the duration of luminescence of the solid powder of the compound of formula (II) after being excited by ultraviolet light is short, and the fitting lifetime value is 2.5 ns, that is, the solid powder of the compound of formula (II) itself has no afterglow property and the luminescence intensity decays rapidly.

[0133] Figure 6 It is the steady-state luminescence and afterglow luminescence spectrogram of the color-tunable organic long-afterglow material in Example 1. From Figure 6 It can be seen that the steady-state luminescence of the color-tunable organic long-afterglow material in Example 1 is around 410 nm, the maximum emission peak of the delayed luminescence is around 600 nm, and the second emission peak is around 555 nm.

[0134] Figure 7 It is the afterglow luminescence spectrogram of the color-tunable organic long-afterglow material in Examples 1-5. From Figure 7 It can be seen that for the color-tunable organic long-afterglow materials prepared in Examples 1-5, the emission peaks of the delayed luminescence are concentrated at three positions, namely 500 nm, 555 nm and 600 nm. As the doping amount of the compound of formula (I) in the main component gradually decreases, the emission peak of the delayed luminescence of the color-tunable organic long-afterglow material gradually shifts from 600 nm to 500 nm, making the afterglow color of the material change from orange-red to yellowish-white.

[0135] Figure 8 It is the afterglow luminescence decay curve diagram of the color-tunable organic long-afterglow material in Examples 1-5. From Figure 8 It can be seen that the lifetimes of the maximum emission peaks of the delayed spectra of the color-tunable organic long-afterglow materials in Examples 1-5 can all reach the millisecond level, and their fitting lifetime values are 0.895 s, 0.972 s, 0.234 s, 0.242 s and 0.302 s respectively, indicating that the materials in Examples 1-5 all have good long-afterglow luminescence properties.

[0136] Figure 9 It is the steady-state luminescence and afterglow luminescence spectrogram of the color-tunable organic long-afterglow material in Example 6. From Figure 9 It can be seen that the steady-state luminescence of the color-tunable organic long-afterglow material in Example 6 is around 410 nm, the maximum emission peak of the delayed luminescence is around 610 nm, and the second emission peak is around 565 nm.

[0137] Figure 10It is the afterglow emission spectrum diagram of the color-tunable organic long afterglow materials in Examples 6-10. It can be seen from Figure 10 that for the color-tunable organic long afterglow materials prepared in Examples 6-10, the emission peaks of the delayed luminescence are concentrated at three positions, namely 505 nm, 565 nm and 610 nm. As the doping amount of the guest molecular formula (Ⅱ) compound in the host component gradually decreases, the emission peak of the delayed luminescence of the color-tunable organic long afterglow material gradually shifts from 610 nm to 505 nm, making the afterglow color of the material change from orange-red to green.

[0138] Figure 11 It is the afterglow luminescence decay curve diagram of the color-tunable organic long afterglow materials in Examples 6-10. It can be seen from Figure 11 that for the color-tunable organic long afterglow materials in Examples 6-10, the lifetimes of the maximum emission peaks of the delayed spectra can all reach the millisecond level, and their fitting lifetime values are 1.049 s, 1.023 s, 0.327 s, 0.435 s and 0.430 s respectively, indicating that the materials in Examples 6-10 all have good long afterglow luminescence properties.

[0139] Figure 12 It is the ultraviolet lamp-excited afterglow photo of the color-tunable organic long afterglow materials in Examples 1-5. It can be seen from Figure 12 that for the color-tunable organic long afterglow materials prepared in Examples 1-5, as the doping amount of the formula (Ⅰ) compound gradually decreases, after the material is excited by the ultraviolet lamp, the afterglow gradually changes from bright orange-red to yellow-white.

[0140] Figure 13 It is the ultraviolet lamp-excited afterglow photo of the color-tunable organic long afterglow materials in Examples 6-10. It can be seen from Figure 13 that for the color-tunable organic long afterglow materials prepared in Examples 6-10, as the doping amount of the formula (Ⅱ) compound gradually decreases, after the material is excited by the ultraviolet lamp, the afterglow gradually changes from bright orange-red to green.

[0141] It can be seen that the afterglow color of the organic long afterglow materials in Examples 1-10 can be adjusted by controlling the doping amount of the guest molecules, and it has good anti-counterfeiting and authenticity identification capabilities when applied to anti-counterfeiting materials.

Claims

1. Use of the compounds of formula (I) and formula (II) in organic long-afterglow materials, and the structural formulas of the compounds of formula (I) and formula (II) are as follows:

2. A color-tunable organic long persistent phosphorescent material, characterized in that, Comprising a main component and a guest molecule doped in the main component; the guest molecule comprises at least one of the compounds of formula (I) and formula (II) recited in claim 1.

3. The color-tunable organic long persistent phosphorescent material according to claim 2, characterized in that, The main component comprises melamine formaldehyde resin.

4. The color-tunable organic long-afterglow material according to claim 2, wherein The doping amount of the guest molecule in the color-tunable organic long-afterglow material is 0.000005wt%-0.05wt%.

5. The color-tunable organic long persistent luminescence material according to any one of claims 2-4, characterized in that, The color-tunable organic long-afterglow material comprises the following preparation raw materials: a guest molecule solution and a melamine formaldehyde resin prepolymer solution.

6. The color-tunable organic long-afterglow material according to claim 5, wherein The concentration of the guest molecule solution is 1-4mg / mL; And / or, the solvent of the guest molecule solution comprises at least one of methanol, ethanol, acetone, dimethyl sulfoxide, N,N-dimethylformamide, tetrahydrofuran, and acetonitrile.

7. The preparation method of the color-tunable organic long-afterglow material according to claim 5 or 6, characterized in that, Comprising the following steps: S1. Mix and react the guest molecule solution and the melamine formaldehyde resin prepolymer solution to obtain a polymer solution; S2. Coat the polymer solution on a carrier and dry it to obtain the color-tunable organic long-afterglow material.

8. The preparation method according to claim 7, wherein The drying temperature is 150-170°C and the time is 20-30min.

9. Use of the color-tunable organic long-afterglow material according to any one of claims 2-6 in anti-counterfeiting, data encryption, functional inks, road signs, and multicolor displays.

10. An anti-counterfeiting material, characterized in that, Comprising the color-tunable organic long-afterglow material according to any one of claims 2-6.

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