Colorful room-temperature phosphorescent material as well as preparation method and application thereof

Abstract

The invention belongs to the field of preparation of pure organic long-afterglow materials, and particularly relates to a colorful room-temperature phosphorescent material as well as a preparation method and application thereof. The preparation method comprises the following steps: dissolving bio-based molecules containing galactomannan to obtain a matrix solution; dissolving boric acid small organic molecules in ammonia water to obtain a guest solution; mixing the two solutions for chemical crosslinking; and drying the mixture to obtain the colorful room-temperature phosphorescent material. Natural biological macromolecules are used as a matrix, water is used as a solvent, and the defects that in the prior art, cost is high, the process is complex and environment friendliness is not achieved are overcome. A rigid network constructed through chemical crosslinking effectively inhibits non-radiative transition, and the material which is excellent in phosphorescence performance, low in cost and environmentally friendly is obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of preparation of pure organic long afterglow materials, and particularly relates to a colorful room temperature phosphorescent material and a preparation method and application thereof. BACKGROUND

[0002] Room temperature phosphorescent materials have great application potential in the fields of information encryption, product anti-counterfeiting, biological imaging and optoelectronic devices due to their unique long lifetime luminescence characteristics. Traditional phosphorescent materials are mostly dependent on compounds containing noble metals or heavy metals, which have problems of high cost, great toxicity and resource scarcity. Therefore, the development of pure organic room temperature phosphorescent materials has become a research hotspot in recent years, which has the advantages of low cost, small toxicity, easy design and modification of structure and the like.

[0003] The key to realizing efficient pure organic room temperature phosphorescence lies in effectively inhibiting the non-radiative transition process of molecules from the excited triplet state to the ground state after excitation. At present, a mainstream technical strategy is to disperse or fix organic small molecules with phosphorescent activity (i.e. phosphorescent guests) in a rigid matrix, so as to limit the vibration and rotation of the guest molecules through the rigid environment provided by the matrix, thereby enhancing phosphorescent emission. In the prior art, a common scheme is to dope benzene boronic acid compounds as phosphorescent guests into a polymer matrix. For example, a technical scheme discloses that benzene boronic acid guest molecules are doped in a semi-aromatic polyimide powder, and a room temperature phosphorescent material with adjustable color is prepared by spin coating or drying. However, the polymer matrix used in this scheme, such as polyimide, is usually artificially synthesized, which has a high raw material cost, and the preparation process may involve the use of organic solvents, which not only makes the process relatively complex, but also may have certain impact on the environment, limiting its large-scale and low-cost application. In addition, such synthetic polymer matrix usually does not have biodegradability.

[0004] Therefore, the technical scheme of the present application is proposed. SUMMARY

[0005] The purpose of the present application is to overcome the defects of high cost, complex preparation process and environmental unfriendliness of the phosphorescent material matrix in the prior art, and to provide a room temperature phosphorescent composite material with lower cost, simple preparation method and green environmental protection, and a preparation method thereof.

[0006] In order to solve the problems existing in the prior art, the present application provides a preparation method of a colorful room temperature phosphorescent material, which comprises the following steps: (1) dissolving a bio-based molecule containing galactomannan in water to obtain a bio-based molecule containing galactomannan solution; (2) dissolving a boronic acid organic small molecule in ammonia water to obtain a phosphorescent dye solution; (3) mixing the galactomannan-containing bio-based molecule aqueous solution with the phosphorescent dye solution to obtain a blending solution; (4) drying the blending solution into a film to obtain the multi-color room-temperature phosphorescent material.

[0007] Preferably, the galactomannan-containing bio-based molecule is Chenopodium album powder or a derivative thereof, guar gum or a derivative thereof, tara gum or a derivative thereof, tara gum or a derivative thereof.

[0008] Preferably, the boronic acid-based organic small molecule is one of p-biphenyl boronic acid, 2-biphenyl boronic acid, 4-biphenyl boronic acid, phenanthrene-9-boronic acid, 1-naphthalene boronic acid, 1-pyrene boronic acid, benzene boronic acid, 9-anthracene boronic acid, 9, 9-dimethylfluorene-2-boronic acid, 9, 9-dimethyl-2, 7-fluorene diboronic acid, 1, 3, 5-tris (4-benzenboronic acid) benzene, 4, 4'-biphenyl diboronic acid, 2, 4, 6-tris (4-carboxyphenyl) -1, 3, 5-triazine, 2, 4, 6-tris [(p-carboxyphenyl) amino]-1, 3, 5-triazine.

[0009] Preferably, the weight ratio of the galactomannan-containing bio-based molecule to the boronic acid-based organic small molecule is 100:0.5~2.

[0010] Preferably, in step (3), the mixing is performed by using one or a combination of more than two of heating, stirring, ultrasonic, and oscillation.

[0011] Preferably, the heating temperature is 70~90℃, and the heating time is 20~40min; and / or, the stirring speed is 60~80r / min, and the stirring time is 10~20min; and / or, the ultrasonic power is 200~400W, the ultrasonic working time is 3s, the intermittent time is 2s, and the total cycle is 200~300; and / or, the oscillation time is 10~15min.

[0012] Preferably, in step (4), the drying is performed by using heating or freeze sublimation.

[0013] Preferably, the heating drying temperature is 60~80℃, and the heating drying time is 4~5h; and / or, the freezing time is 3~4h, and the sublimation time is 24~28h.

[0014] Based on the same technical concept, another aspect of the present application provides a multi-color room-temperature phosphorescent material obtained by the above preparation method.

[0015] Based on the same technical concept, another aspect of the present application provides an application of the multi-color room temperature phosphorescent material in pattern display, screen printing, 3D printing or information anti-counterfeiting.

[0016] The present application has the following advantages: 1. Low cost and green: The present application uses natural, renewable and biodegradable biological macromolecules (such as sesbania powder and guar gum) as the matrix, replacing expensive and difficult-to-degrade synthetic polymers, significantly reducing material costs, and the raw materials are widely available, green, and biocompatible.

[0017] 2. Simple and safe preparation process: The preparation method of the present application mainly uses water as the solvent, avoiding the use of toxic and harmful organic solvents, and the process is simple, the reaction conditions are mild, easy to operate, and low in energy consumption, in line with the concept of green chemistry, and suitable for large-scale industrial production.

[0018] 3. Excellent phosphorescent performance and unique function: The chemical cross-linking between the large number of hydroxyl groups in the biological macromolecule matrix and the boronic acid groups of the phosphorescent guest molecules forms a stable rigid network structure, effectively inhibiting the non-radiative transition of the guest molecules, thereby obtaining room temperature phosphorescent performance with long lifetime, high efficiency and color adjustable.

[0019] In addition, based on the hydrophilic properties of the biological matrix, the material also exhibits unique water-induced or heat-induced reversible erasing function, and has broad application prospects in the field of dynamic information encryption and anti-counterfeiting. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0021] Figure 1 is a comparison chart of the long afterglow phenomenon of the multi-color room temperature phosphorescent material obtained in Examples 1-4.

[0022] Figure 2 is a phosphorescent spectrum chart of the multi-color room temperature phosphorescent material obtained in Examples 1-4.

[0023] Figure 3 is a phosphorescent lifetime decay curve chart corresponding to Examples 1-4.

[0024] Figure 4 is an application situation chart of the multi-color room temperature phosphorescent material obtained in Examples 1, 2 and 4 in information anti-counterfeiting.

[0025] Figure 5 is the application case diagram of information encryption corresponding to the multi-color room temperature phosphorescent material obtained in Example 1, 2.

[0026] Figure 6 is the application case diagram of screen printing corresponding to the multi-color room temperature phosphorescent material obtained in Example 1, 2.

[0027] Figure 7 is the application case diagram of 3D forming corresponding to the multi-color room temperature phosphorescent material obtained in Example 1-4.

[0028] Figure 8 is a diagram of the multi-color room temperature phosphorescent material obtained in Example 1, 2, 4 prepared into a circular film with a diameter of 3 cm. DETAILED DESCRIPTION

[0029] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0030] Example 1 The present embodiment provides a preparation method of a multi-color room temperature phosphorescent material, which comprises the following steps: (1) 100 milligrams (mg) of sesbania powder (as a bio-based molecule containing galactomannan) is accurately weighed and placed in a 25 milliliter (mL) beaker, and 10 milliliters (mL) of deionized water is added to the beaker. The beaker is placed on a magnetic stirrer with heating and stirring functions, and the magnetic stirring is started, with the speed set to 500 revolutions per minute (r / min). Under the condition of continuous heating and stirring, the sesbania powder gradually absorbs water, swells and dissolves, forming a uniform and viscous matrix solution (bio-based molecule solution containing galactomannan). This process takes about 30 minutes. The heating and stirring here serve as a preferred physical auxiliary means, which can significantly accelerate the hydration and dissolution process of the sesbania powder macromolecule, and ensure the formation of a uniform and non-aggregated solution, laying a foundation for the subsequent uniform cross-linking reaction.

[0031] (2) Accurately weigh 1 milligram (mg) of 4-biphenylboronic acid (as a boronic acid organic small molecule) into a 25 milliliter (mL) beaker. Add 0.2 milliliter (mL) of ammonia water and 0.8 mL of deionized water into the beaker, and continuously stir with a glass rod until the 4-biphenylboronic acid is completely dissolved to form a clear and transparent solution, at which time the solution is weakly alkaline. The solubility of 4-biphenylboronic acid in pure water is low. By adding an alkaline substance (such as sodium hydroxide, ammonia water, etc.) to adjust the pH value of the solution to alkaline, the boronic acid group can be deprotonated to form [B(OH)4] - ions, thereby greatly increasing its solubility in water, obtaining a homogeneous guest solution (phosphor dye solution). This step is the key to ensuring that the phosphor guest molecules can be uniformly dispersed at the molecular level and effectively react with the matrix.

[0032] (3) The prepared sesbania gum matrix solution in step (1) is continuously stirred on a magnetic stirrer and heated to 80°C. Then, using a pipette, the prepared 4-biphenylboronic acid guest solution in step (2) is slowly and dropwise added to the vigorously stirred sesbania gum matrix solution. After mixing, continue to react at 80°C and 500 revolutions per minute for 30 minutes. In this process, the dissolved and activated phosphor guest molecules (4-biphenylboronic acid) uniformly diffuse into the network of sesbania gum macromolecular chains, and the boronic acid group reacts with the cis-hydroxyl group on the sesbania gum molecular chain to form a chemical cross-linking structure (borate ester bond). As the reaction proceeds, the viscosity of the solution may increase slightly, indicating the formation of an intermolecular cross-linking network. Adequate mixing and reaction time ensure that the cross-linking reaction proceeds sufficiently, so that as many guest molecules as possible are immobilized.

[0033] (4) The viscous mixed solution obtained in step (3) is uniformly poured into a clean polytetrafluoroethylene mold, and allowed to flow naturally into a layer of uniform thickness liquid film. Subsequently, the mold is placed in a constant temperature air drying oven at 80°C for drying. After about 4 hours of drying, the solvent (mainly water) is completely evaporated, and finally a semi-transparent, flexible solid thin film is obtained at the bottom of the mold. This thin film is the prepared colorful room-temperature phosphor material (organic long afterglow material BpB-SGM).

[0034] It should be emphasized that as another drying method, the mixed solution can also be freeze-dried, i.e., first frozen at a low temperature (such as -80°C) for 3h, and then the water is removed by sublimation under vacuum conditions (24h), and the colorful room-temperature phosphor material can also be obtained.

[0035] For the sake of understanding the present application, Example 1 is taken as an example for illustration: In this embodiment, the galactomannan-containing biobased molecule is specifically amaranth meal. Amaranth meal is a natural plant polysaccharide, and its main chemical component is galactomannan. The main chain of galactomannan is composed of mannose units connected by β-(1→4) glycosidic bonds, and the side chain is connected with galactose units by α-(1→6) glycosidic bonds. The most notable feature of this molecular structure is the abundance of functional groups - hydroxyl groups. These hydroxyl groups not only endow amaranth meal with good hydrophilicity, but more importantly, they can serve as active sites for chemical reactions, especially the cis-diol structure at adjacent positions, providing a basis for subsequent chemical cross-linking with phosphorescent guest molecules. The choice of amaranth meal as the galactomannan-containing biobased molecule is not only because of its wide availability, extremely low cost, and complete biodegradability, which meets the requirements of green chemistry and sustainable development, but also because its molecular chain can form a three-dimensional network structure in aqueous solution, providing an ideal framework for constructing a rigid environment.

[0036] The phosphorescent guest molecule in this embodiment is specifically 4-biphenylboronic acid. 4-Biphenylboronic acid is a pure organic small molecule, and its structure contains two key parts. One part is the aromatic core, i.e., biphenyl, which serves as the light-emitting unit. Biphenyl has a large conjugated π-electron system, and after being excited by ultraviolet light or other energy, it can effectively populate the excited triplet state through an intersystem crossing process, which is the electronic energy level basis for the phosphorescence phenomenon. The other part is the boronic acid group, i.e., -B(OH)2, which serves as the cross-linking unit. This boronic acid group has unique chemical reactivity and can undergo a reversible condensation reaction with molecules containing ortho or cis-diol structures under suitable conditions (e.g., weak alkaline environment), forming stable five-membered or six-membered ring borate ester bonds.

[0037] The core technical concept of this embodiment is to covalently bond the phosphorescent guest molecule to the biobased molecule through a chemical reaction, forming a stable chemical cross-linking structure. Specifically, it utilizes the boronic acid group on the phosphorescent guest molecule to undergo a dehydration condensation reaction with the hydroxyl groups (especially the cis-diol structure) on the galactomannan chain of the biobased molecule (amaranth meal), generating a borate ester bond. This chemical cross-linking structure firmly "anchors" the phosphorescent guest molecule, which can otherwise move freely, at a specific position on the three-dimensional polymer network framework composed of amaranth meal. When the multicolor room-temperature phosphorescent material is formed, the rigid network structure of the biobased molecule greatly restricts the intramolecular vibration and rotation of the anchored phosphorescent guest molecule. After photoexcitation, the guest molecule in the excited triplet state is effectively inhibited from returning to the ground state through non-radiative transitions (such as vibrational relaxation) due to the restricted motion, significantly improving the phosphorescent quantum yield and allowing more energy to be emitted in the form of phosphorescence. Ultimately, bright and persistent phosphorescence can be observed at room temperature.

[0038] Example 2 This embodiment aims to illustrate that by changing the kind of phosphorescent guest molecules, the luminescent color of the obtained colorful room-temperature phosphorescent material can be conveniently regulated, and the flexibility of the technical scheme of the present application in realizing colorful phosphorescence is demonstrated.

[0039] The colorful room-temperature phosphorescent material of this embodiment is the same as that of embodiment 1 in that the bio-based molecules thereof also adopt sesbania gum, which is rich in hydroxyl groups available for reaction. The difference lies in that the boronic acid-based organic small molecule selected in this embodiment is phenanthrene-9-boronic acid.

[0040] In this embodiment, the phosphorescent guest molecule is specifically phenanthrene-9-boronic acid. In the molecular structure of phenanthrene-9-boronic acid, the aromatic core is phenanthryl, which is a polycyclic aromatic hydrocarbon structure fused by three benzene rings, has a larger conjugated system than biphenyl, and has a different electronic energy level structure. It also has a boronic acid group for chemical crosslinking.

[0041] The preparation method of this embodiment is basically consistent with the process described in embodiment 1, and only the raw material is replaced in step (2). The specific preparation process is as follows: (1) The same as in embodiment 1, 100 milligrams (mg) of sesbania gum was dissolved in 10 milliliters (mL) of deionized water, and a uniform matrix solution was obtained under heating and stirring.

[0042] (2) 1 milligram (mg) of phenanthrene-9-boronic acid (as a boronic acid-based organic small molecule) was weighed and replaced 4-biphenylboronic acid, and was also dissolved in 1 milliliter (mL) of weak alkaline aqueous solution (0.2 mL of ammonia water + 0.8 mL of deionized water) to obtain a clear guest solution. The aromatic core of phenanthrene-9-boronic acid is phenanthryl, and its excited state energy is different from that of 4-biphenylboronic acid, which is the fundamental reason for realizing color regulation.

[0043] (3) The same as in embodiment 1, the phenanthrene-9-boronic acid guest solution was slowly added to the hot sesbania gum matrix solution, and the reaction was continuously stirred at 80°C for 30 minutes. In this process, the boronic acid group of phenanthrene-9-boronic acid reacts with the hydroxyl group of sesbania gum to form a chemical crosslinking structure, anchoring the phenanthryl luminophore in the matrix network.

[0044] (4) The same as in embodiment 1, the mixture after reaction was poured into a polytetrafluoroethylene mold, and was dried at 60°C for 4h to obtain a colorful room-temperature phosphorescent material (organic long afterglow material PheB-SGM).

[0045] Embodiment 3 This embodiment aims to illustrate that by changing the kind of phosphorescent guest molecules, the luminescent color of the obtained colorful room-temperature phosphorescent material can be conveniently regulated, and the flexibility of the technical scheme of the present application in realizing colorful phosphorescence is demonstrated.

[0046] The multi-color room temperature phosphorescent material of the present example is the same as that of Example 1 in that the bio-based molecule also uses sesbania powder, which is rich in hydroxyl groups available for reaction. The difference is that the boronic acid organic small molecule selected in the present example is 1-naphthalene boronic acid.

[0047] The preparation method of the present example is basically consistent with the process described in Example 1, only the raw material is replaced in step (2). The specific preparation process is as follows: (1) The same as Example 1, 100 milligrams (mg) of sesbania powder was dissolved in 10 milliliters (mL) of deionized water under heating conditions to obtain a uniform matrix solution.

[0048] (2) 1 milligram (mg) of 1-naphthalene boronic acid (as a boronic acid organic small molecule) was weighed instead of 4-biphenyl boronic acid, and was also dissolved in 1 milliliter (mL) of weak alkaline aqueous solution (0.2 mL of ammonia water + 0.8 mL of deionized water) to obtain a clear guest solution. The aromatic core of 1-naphthalene boronic acid is naphthyl, and its excited state energy is different from that of 4-biphenyl boronic acid, which is the fundamental reason for realizing color regulation.

[0049] (3) The same as Example 1, the 1-naphthalene boronic acid guest solution was slowly added to the hot sesbania powder matrix solution, and the stirring reaction was continued at 80°C for 30 minutes. In this process, the boronic acid group of 1-naphthalene boronic acid reacts with the hydroxyl group of sesbania powder to form a chemical cross-linking structure, anchoring the phenanthrene luminophore in the matrix network.

[0050] (4) The same as Example 1, the mixture after reaction was poured into a polytetrafluoroethylene mold, and dried at 60°C for 4h to obtain a multi-color room temperature phosphorescent material (organic long afterglow material NapB-SGM).

[0051] Example 4 The present example further expands the phosphorescent color regulation range and verifies the compatibility of the technical scheme of the present application to various aromatic boronic acid guest molecules.

[0052] The multi-color room temperature phosphorescent material of the present example is the same as that of Example 1 in that the bio-based molecule also uses sesbania powder, which is rich in hydroxyl groups available for reaction. The difference is that the boronic acid organic small molecule selected in the present example is 1-naphthalene boronic acid. The aromatic core 121 of 1-naphthalene boronic acid is pyrene group, which is a large conjugated planar aromatic hydrocarbon fused by four benzene rings, and its excited triplet state energy level is lower, which is expected to produce longer wavelength phosphorescent emission.

[0053] The preparation method of the present example is basically consistent with the process described in Example 1, and the specific steps are as follows: (1) The same as Example 1, the sesbania powder matrix solution was prepared.

[0054] (2) 1 milligram (mg) of 1-pyrene boronic acid (as a boronic acid organic small molecule) was weighed and dissolved in a weakly alkaline aqueous solution to prepare a guest solution, using the same method as in Example 1.

[0055] (3) The 1-pyrene boronic acid guest solution was mixed with the sesbania gum matrix solution and reacted at 80°C to form a chemical cross-linking structure.

[0056] (4) The mixture was dried in an oven at 70°C for 4 h, and then cooled to room temperature to obtain the final multi-color room-temperature phosphorescent material (organic long afterglow material PyB-SGM).

[0057] Verification Example Figure 1 The multi-color room-temperature phosphorescent materials prepared for the guest molecules used in Examples 1-4 emitted bright fluorescence under ultraviolet light irradiation, and long afterglow phenomenon appeared after the ultraviolet light was turned off, proving that the preparation of multi-color room-temperature phosphorescent materials can be achieved by doping different guests, among which BpB-SGM (Example 1) can achieve 8s blue afterglow, PheB-SGM (Example 2) can achieve 12s green afterglow, NapB-SGM (Example 3) can achieve 5s yellow-green afterglow, and PyB-SGM (Example 4) can achieve 1.5s red afterglow.

[0058] Figure 2 The phosphorescence spectrum of the multi-color room-temperature phosphorescent materials prepared in Examples 1-4 is shown in the figure. As can be seen from the figure, the phosphorescence spectra of the multi-color room-temperature phosphorescent materials prepared in Examples 1-4 under excitation at 310 nm, 310 nm, 310 nm, and 365 nm, respectively, have phosphorescence spectrum peaks at 480 nm, 513 nm, 522 nm, and 613 nm, respectively.

[0059] Figure 3 The phosphorescence lifetime decay curves corresponding to Examples 1-4 are shown in the figure, showing that the room-temperature phosphorescence lifetimes are 1649.28 ms, 1351.52 ms, 587.58 ms, and 171.69 ms, respectively.

[0060] Figure 4 The application of the multi-color room-temperature phosphorescent materials prepared in Examples 1, 2, and 4 to information anti-counterfeiting is shown in the figure. After excitation by an ultraviolet lamp, different room-temperature phosphorescence afterglow times can be read as "E", "F", and "I", respectively. These numerical information cannot be copied and have high security and unbreakability.

[0061] Figure 5The application case diagram of the corresponding information encryption of the multi-color room temperature phosphorescent material prepared in examples 1 and 2. By tracking the complete afterglow information, the Morse code can be obtained completely, and the hidden information "BIPT" can be read out. The excitation-dependent afterglow of the multi-color RTP soybean meal provides additional protection for the information encryption system.

[0062] Figure 6 The application case diagram of the corresponding screen printing of the multi-color room temperature phosphorescent material prepared in examples 1 and 2. The two materials are printed on A4 paper through a screen printing plate, and a pattern with different afterglow colors is obtained.

[0063] Figure 7 The application case diagram of the corresponding 3D molding of the multi-color room temperature phosphorescent material prepared in examples 1, 2, 3 and 4. By placing the material in a mold, a 3D model with different shapes is obtained by freeze vacuum sublimation.

[0064] Figure 8 The multi-color room temperature phosphorescent materials prepared in examples 1, 2 and 4 are prepared into a circular film with a diameter of 3 cm. After ultraviolet light irradiation, uniform blue, green and red phosphorescence is observed. After writing "R", "T" and "P" on it with a brush dipped in water, obvious "R", "T" and "P" letters are observed under ultraviolet light irradiation. After heating, the letters disappear, and uniform blue, green and red phosphorescence is obtained. It shows that the material has the prospect of recording and water-thermal stimulation cycle application under water and thermal stimulation.

[0065] Through examples 1-4, it is proved that the multi-color room temperature phosphorescent material protected by the application can be widely selected from at least one of p-biphenyl boronic acid, phenanthrene-9-boronic acid, 1-naphthalene boronic acid, 1-pyrene boronic acid and the like. By selective use of these guest molecules with different aromatic cores, or even by blending them in different proportions, the phosphorescent color and lifetime of the final material can be accurately controlled, realizing multi-color and long-life room temperature phosphorescence in the full spectral range, greatly enriching the functionality and application scenarios of the material.

[0066] The above is only a specific embodiment of the application, but the protection scope of the application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the application, which should be covered within the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. A method for preparing a multicolored room-temperature phosphorescent material, characterized in that, The preparation method includes the following steps: (1) Dissolve the bio-based molecules containing galactomannan in water to obtain a bio-based molecule solution containing galactomannan; (2) Dissolve boric acid-based organic small molecules in ammonia water to obtain a phosphorescent dye solution; (3) The aqueous solution of the bio-based molecule containing galactomannan is mixed with the phosphorescent dye solution to obtain a blend; (4) The blended liquid is dried into a film to obtain the multicolor room temperature phosphorescent material.

2. The method for preparing the multicolored room-temperature phosphorescent material according to claim 1, characterized in that, The bio-based molecules containing galactomannan are guar gum or its derivatives, guar gum or its derivatives, carob gum or its derivatives, and tara gum or its derivatives.

3. The method for preparing the multicolored room-temperature phosphorescent material according to claim 1, characterized in that, The boronic acid organic small molecule is one of the following: p-biphenylboronic acid, 2-biphenylboronic acid, 4-biphenylboronic acid, phenanthrene-9-boronic acid, 1-naphthoboronic acid, 1-pyreneboronic acid, phenylboronic acid, 9-anthrabenonic acid, 9,9-dimethylfluorene-2-boronic acid, 9,9-dimethyl-2,7-fluorenediboronic acid, 1,3,5-tris(4-phenylboronic acid)benzene, 4,4'-biphenyldiboronic acid, 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine, and 2,4,6-tris[(p-carboxyphenyl)amino]-1,3,5-triazine.

4. The method for preparing the multicolored room-temperature phosphorescent material according to claim 1, characterized in that, The weight ratio of the galactomannan-containing bio-based molecule to the boric acid-based organic small molecule is 100:0.5~2.

5. The method for preparing the multicolored room-temperature phosphorescent material according to claim 1, characterized in that, In step (3), the mixing method is to use one or more of the following methods: heating, stirring, ultrasound, and vibration.

6. The method for preparing the multicolored room-temperature phosphorescent material according to claim 5, characterized in that: The heating temperature is 70~90℃, and the heating time is 20~40min; And / or, the stirring speed is 60~80 r / min, and the stirring time is 10~20 min; And / or, the power of the ultrasound is 200~400W, the working time of the ultrasound is 3s, the interval time is 2s, and there are a total of 200~300 cycles; And / or, the oscillation time is 10~15 min.

7. The method for preparing the multicolored room-temperature phosphorescent material according to claim 1, characterized in that, In step (4), the drying method is to use heating or freeze sublimation to dry.

8. The method for preparing the multicolored room-temperature phosphorescent material according to claim 5, characterized in that: The heating and drying temperature is 60~80℃, and the heating and drying time is 4~5 hours; And / or, the freezing time is 3-4 hours, and the sublimation time is 24-28 hours.

9. The multicolored room-temperature phosphorescent material obtained by the preparation method according to any one of claims 1 to 8.

10. The application of the colorful room temperature phosphorescent material of claim 9 in pattern display, screen printing, 3D printing or information anti-counterfeiting.

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