High-contrast time-dependent color-changing room-temperature phosphorescent material and use method thereof for multi-dimensional anti-counterfeiting

Abstract

The invention discloses a high-contrast time-dependent color-changing room-temperature phosphorescent material and a use method thereof for multi-dimensional anti-counterfeiting. The method comprises the following steps: under a heating condition, embedding 1-pyrenecarboxylic acid into konjac mannan through non-covalent bond interaction to obtain the high-contrast time-dependent color-changing room-temperature phosphorescent material capable of being shaped in multiple ways, and carrying out silk-screen printing, film laying and 3D printing on the solution after the reaction is finished to obtain a time-dependent color-changing room-temperature phosphorescent pattern, a bendable folding film and 3D phosphorescent foam, wherein the phosphorescent color of an object is converted from red to blue-green. The preparation process is simple, rapid, green and environment-friendly, large-scale industrial preparation can be achieved, and construction of the high-mechanical-strength time-dependent color-changing room-temperature phosphorescent object is achieved. The technology can effectively improve the problems of single static color, poor processability and small application dimension of the room-temperature phosphorescent material, is an important beginning of application and development of multi-dimensional phosphorescent devices, and provides a new direction for industrial production of the room-temperature phosphorescent material.

Description

Technical Field

[0001] The present invention belongs to the technical field of room temperature phosphorescence, and in particular relates to a high-contrast time-dependent color-changing room temperature phosphorescent material and a method of using the same for multi-dimensional anti-counterfeiting. Background Art

[0002] Room temperature phosphorescent materials have unique optical properties and ultra-long service life. They have unique advantages and broad application prospects in the fields of information anti-counterfeiting and dynamic information encryption. To date, most room temperature phosphorescent materials are composed of inorganic or organic metal materials, which are usually high in production cost, non-renewable, complex in preparation process, and have certain cytotoxicity. Compared with heavy metal room temperature phosphorescent materials, organic room temperature phosphorescent materials have many advantages, including simplified manufacturing process, low cost, easy processing and stronger mechanical properties. However, organic room temperature phosphorescent materials currently face the challenges of limited afterglow color diversity and poor color tunability. Most organic room temperature phosphorescent materials show static and monotonous afterglow colors. In order to meet the urgent need to enhance information security, it is necessary to develop room temperature phosphorescent materials with dynamic color tunability. At present, there are three main methods for preparing time-dependent color-changing phosphorescent materials: (1) preparing time-dependent color-changing carbon dots or carbonized polymer dots; (2) doping multiple chromophores in polymers; (3) activating thermally activated delayed fluorescence and room temperature phosphorescence simultaneously in molecular crystals. However, these methods usually require tedious and time-consuming preparation processes, which means increased difficulty, reduced reproducibility, and difficulty in practical production applications. Therefore, from an application perspective, it would be highly desirable to adopt a direct and environmentally friendly strategy to develop high-contrast time-dependent color-changing phosphorescent materials without extensive chemical modification. Summary of the invention

[0003] In order to realize the advanced information encryption and multi-dimensional anti-counterfeiting functions of biomass room temperature phosphorescent materials, and to overcome the problems of current organic room temperature phosphorescent materials such as static and single afterglow color, complex preparation process, and material form that cannot meet a variety of daily applications, the primary goal of the present invention is to provide a high-contrast time-dependent color-changing room temperature phosphorescent material.

[0004] Another object of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a high-contrast time-dependent color-changing room temperature phosphorescent material that can be prepared by large-scale screen printing, film casting and 3D printing technology and a method of using the same for multi-dimensional anti-counterfeiting. The method is to embed pyrene derivatives with different functional groups into konjac glucomannan through non-covalent interactions, thereby converting konjac glucomannan into a high-contrast time-dependent color-changing room temperature phosphorescent material that can be shaped in multiple ways. The multi-path shaping process can be achieved through screen printing, film casting and 3D direct writing printers. Large-scale preparation not only realizes the high-value utilization of konjac glucomannan, but also can realize pattern printing of various sizes, casting into films of various sizes, and various scales of 3D direct writing printers for the preparation of three-dimensional room temperature phosphorescent materials of different shapes and sizes. The high-contrast time-dependent color-changing room temperature phosphorescent material that can be shaped in multiple dimensions has a wide range of applications, and provides additional anti-counterfeiting encryption functions in the time dimension and space dimension, and has important practical application value.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A high-contrast time-dependent color-changing room temperature phosphorescent material and a method for using the same for multi-dimensional anti-counterfeiting, comprising the following steps:

[0007] Step 1: adding konjac glucomannan powder to the pyrene derivative dispersion to obtain a konjac glucomannan solution in a heated environment.

[0008] Step 2: The konjac glucomannan solution obtained above is respectively subjected to screen printing, film forming, 3D printing, drying and freeze drying by screen printing, film casting, 3D direct writing printer, air drying oven and freeze drying machine to obtain high-contrast time-dependent color-changing room temperature phosphorescent materials of different shapes.

[0009] The heating time of step 1 is 20 minutes and the heating temperature is 80°C.

[0010] The morphology of the time-dependent color-changing room temperature phosphorescent material in step 2 varies. Depending on the functional groups of the pyrene derivatives, the color of the time-dependent color-changing room temperature phosphorescent material covers the entire visible light region. After ultraviolet excitation, the phosphorescent color achieves a large leap from red to blue-green.

[0011] Large-scale preparation of multi-morphological, high-contrast time-dependent color-changing room-temperature phosphorescent materials can not only be used for phosphorescent decorations, but also realize multi-dimensional dynamic information anti-counterfeiting and data encryption.

[0012] The present invention has the following beneficial effects:

[0013] 1. The present invention embeds pyrene derivatives into konjac glucomannan through non-covalent interactions to obtain a konjac glucomannan solution, thereby converting konjac glucomannan into a high-contrast time-dependent color-changing room temperature phosphorescent material that can be shaped in multiple ways, and uses screen printing, casting and 3D direct writing printers to prepare multi-morphological, high-contrast time-dependent color-changing room temperature phosphorescent materials, which are used as phosphorescent decorations and dynamic information anti-counterfeiting and data encryption in different dimensions. The advantage of the present invention is that the high-contrast time-dependent color-changing room temperature phosphorescent material itself has no color, the encrypted information is invisible under sunlight and ultraviolet light, and the encrypted information can be observed after removing the excitation light source, which can be applied to information anti-counterfeiting and encryption that requires time channels and space dimension channels. Secondly, using screen printing, casting and 3D printing processes, it is possible to achieve industrial large-scale production of time-dependent color-changing room temperature phosphorescent materials in a variety of required forms, realizing the practical application value of time-dependent color-changing room temperature phosphorescent materials in daily life, and also providing a new direction for the high-value utilization of biomass. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Preparation of high-contrast time-dependent color-changing room temperature phosphorescent patterns by screen printing (above); preparation of high-contrast time-dependent color-changing room temperature phosphorescent films of different shapes (middle); preparation of high-contrast time-dependent color-changing three-dimensional room temperature phosphorescent foams by 3D printing (below)

[0015] Figure 2 Normalized steady-state photoluminescence and phosphorescence spectra of the time-dependent color-changing stereoscopic room temperature phosphorescent foam in Example 3 Figure 3 The time-dependent phosphorescence spectrum of the time-dependent color-changing stereoscopic room temperature phosphorescent foam in Example 3 (upper figure) and the corresponding delayed phosphorescence spectrum of the delayed time (lower figure)

[0016] Figure 4 The trajectory of the time-dependent color-changing stereoscopic room temperature phosphorescent foam in the color coordinate diagram in Example 3

[0017] Figure 5 Phosphorescence decay curve of high contrast time-dependent color-changing room temperature phosphorescent foam in Example 3 DETAILED DESCRIPTION

[0018] Example 1

[0019] Using konjac glucomannan as raw material, pyrene derivatives were embedded into konjac glucomannan by non-covalent interaction to obtain a mixed solution, and then a multi-morphological time-dependent color-changing room temperature phosphorescent material was obtained by screen printing, film casting and 3D printing technology. The specific preparation steps are as follows:

[0020] Weigh 4 mg of 1-pyrenecarboxylic acid and disperse it evenly in 20 mL of water, add 1 g of konjac glucomannan, and react at 80°C for 20 min. After the reaction, the resulting solution is printed and dried by screen printing and a forced air drying oven to obtain a time-dependent color-changing room temperature phosphorescent pattern, and the pattern phosphorescence color changes from red to blue-green.

[0021] Example 2

[0022] Weigh 4 mg of 1-pyrenecarboxylic acid and disperse it evenly in 20 mL of water, add 1 g of konjac glucomannan, and react at 80°C for 20 min. After the reaction, the resulting solution is laid on a polytetrafluoroethylene plate and dried in a forced air drying oven to obtain a time-dependent color-changing room temperature phosphorescent film. The film can be bent and folded into different shapes, and the film phosphorescence color ranges from red to blue-green.

[0023] Example 3

[0024] Weigh 4 mg of 1-pyrenecarboxylic acid and disperse it evenly in 12 mL of water, add 1 g of konjac glucomannan, and react at 80°C for 20 min. After the reaction, the resulting solution is 3D printed and freeze-dried by a 3D direct writing printer and a freeze dryer, respectively, to obtain a three-dimensional time-dependent color-changing room temperature phosphorescent foam, and the phosphorescent color of the three-dimensional foam ranges from red to blue-green.

Claims

1. A high-contrast time-dependent color-changing room temperature phosphorescent material and a method for using the same for multi-dimensional anti-counterfeiting, characterized in that: The following steps are involved: 1) Weigh a certain amount of pyrene derivatives with different functional groups and disperse them in deionized water to obtain a pyrene derivative dispersion. 2) Add a certain amount of konjac glucomannan powder to the pyrene derivative dispersion, place it at 80° C. for reaction for 20 min, and after the reaction is completed, let the solution stand for 12 h to defoam and set aside. 3) printing a pattern on the object to be printed by screen printing the solution prepared in step 2), and drying to obtain a high-contrast time-dependent color-changing room temperature phosphorescent pattern; The solution is evenly spread on a polytetrafluoroethylene plate and dried to obtain a high-contrast time-dependent color-changing room temperature phosphorescent film, which is then bent and folded into different objects. The film is 3D printed using a 3D direct writing printer and freeze-dried using a freeze dryer to obtain a high-contrast time-dependent color-changing three-dimensional room temperature phosphorescent foam.

2. The high-contrast time-dependent color-changing room temperature phosphorescent material and the method of using the same for multi-dimensional anti-counterfeiting according to claim 1, characterized in that: In step 1), the dispersion of pyrene derivatives with different functional groups is 1-pyrenecarboxylic acid, 1-hydroxypyrene, 1-pyrenecarboxaldehyde, 1-pyrenemethanol, 1-pyreneboric acid, and pyrene.

3. The high-contrast time-dependent color-changing room temperature phosphorescent material and the method of using the same for multi-dimensional anti-counterfeiting according to claim 1, characterized in that: In step 2), the weight ratio of the konjac glucomannan and the pyrene derivatives with different functional groups is 1:1 to 1:10000.

4. The high-contrast time-dependent color-changing room temperature phosphorescent material and the method of using the same for multi-dimensional anti-counterfeiting according to claim 1, characterized in that: In step 3), the concentration of konjac glucomannan in the screen printing ink is 0.05 g / mL.

5. The high-contrast time-dependent color-changing room temperature phosphorescent material and the method of using the same for multi-dimensional anti-counterfeiting according to claim 1, characterized in that: In step 3), the concentration of konjac glucomannan in the film-laying ink is 0.05 g / mL.

6. The high-contrast time-dependent color-changing room temperature phosphorescent material and the method of using the same for multi-dimensional anti-counterfeiting according to claim 1, characterized in that: In step 3), the concentration of konjac glucomannan in the 3D printing ink is 0.08 g / mL, and the printing speed of the 3D direct writing printer is 10 mL / h.

7. The high-contrast time-dependent color-changing room temperature phosphorescent material and the method of using the same for multi-dimensional anti-counterfeiting according to claim 1 are used in the fields of advanced information encryption, phosphorescent decorations, dynamic anti-counterfeiting, etc.

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