A self-activated long afterglow material with multi-mode luminescence and its preparation method and application

Abstract

The present invention discloses a self-activated long afterglow material with multi-mode luminescence, a preparation method and an application thereof, which realizes the effective regulation of the multi-mode luminescence performance of phosphors and can be applied to fields such as information encryption and anti-counterfeiting. The present invention is based on a defect-rich matrix CaGa4O7, through a simple Pb 2+ Doping substitution of Ca 2+ Regulate the concentration and depth of defect states in the matrix to achieve Ca 1‑x Ga4O7:xPb 2+ The effective regulation of multi-mode optical properties such as phosphor afterglow intensity and decay time, photochromism degree and excitation time-dependent fluorescence, and the combination of multi-mode optical properties overcome the problem of single mode of traditional encryption and anti-counterfeiting technology, making it have great application value in the fields of information encryption and anti-counterfeiting.

Description

Technical Field

[0001] The invention relates to a self-activated long afterglow material with multi-mode luminescence, a preparation method and application thereof, and belongs to the technical field of inorganic luminescence. Background Art

[0002] With the rapid development of society, the economy, and science and technology, the emergence of counterfeit and shoddy goods has not only seriously disrupted market order but also severely damaged the image of companies and the interests of consumers. Therefore, to address the long-standing global anti-counterfeiting problem, the development of advanced anti-counterfeiting methods is urgent. Researchers have successively developed fluorescent information anti-counterfeiting encryption technologies based on rare earth element-doped inorganic phosphors, organic small molecules, quantum dots, and metal-organic frameworks. Inorganic phosphors play a crucial role in anti-counterfeiting due to their excellent optical properties (rich luminescence colors, narrow emission peaks, and high brightness). Unfortunately, these fluorescent materials are mostly single-mode information decoding in anti-counterfeiting applications. That is, their emission color remains unchanged under a fixed excitation. Therefore, their anti-counterfeiting level depends largely on the scarcity of the stimulation mode or emission type. However, as the exposure time of these technologies increases, materials with similar properties are constantly being developed, and the risk of counterfeiting increases dramatically.

[0003] In response to the above problems, traditional single-mode luminescent materials are being upgraded to dynamic multi-mode single-component luminescent materials, achieving high-level anti-counterfeiting in spatial and temporal dimensions. For example, Professor Xu Yan of Northeastern University introduced Bi into the self-activated matrix MgGa2O4. 3+ , through the depth of the defect engineering to achieve the dynamic transformation of green or near-infrared to blue-white luminescence, successfully applied to anti-counterfeiting and information encryption. Professor Chen Baojiu of Dalian Maritime University prepared Cr 3+ Doped Zn3Ga2Ge2O 10 Self-activated long afterglow material, doped Cr 3+ Not only did they achieve visible light tuning from green, light pink, to deep red, but they also shifted the afterglow color from yellow to red, successfully developing an anti-counterfeiting solution for smartphone recognition. Therefore, dynamic multi-mode luminescence can hide confidential information within the same set of labels, such as real-time changing patterns, multi-color anti-counterfeiting QR codes, and dynamic digital codes. This anti-counterfeiting method offers extremely high security and flexibility, and has broad application prospects. However, there are relatively few reports on self-activated long-afterglow materials and the regulation of luminescence properties. Summary of the Invention

[0004] The purpose of the present invention is to provide a self-activated long afterglow material with multi-mode luminescence, a preparation method and an application. 2+ Doping can regulate the defect concentration and depth of CaGa4O7 matrix to achieve Ca1-x Ga4O7:xPb 2+ The effective regulation of multi-mode optical properties such as phosphor afterglow intensity and decay time, photochromism degree and excitation time-dependent fluorescence, and the combination of multi-mode optical properties overcome the problem of single mode of traditional encryption and anti-counterfeiting technology, making it applicable in fields such as information encryption and anti-counterfeiting.

[0005] The technical solution adopted by the present invention is:

[0006] The present invention provides a self-activated long afterglow luminescent material with multi-mode luminescence, the chemical formula of which is Ca 1-x Ga4O7:xPb 2+ Where 0≤x≤0.1; the Ca 1-x Ga4O7:xPb 2+ Based on the monoclinic C2 / c space group of CaGa4O7, Ga 3+ Site and Ca 2 + The sites are respectively associated with 4 and 5 O 2- The atoms combine to form GaO4 triangular pyramid and CaO5 triangular bipyramid, and the GaO4 triangular pyramid and CaO5 triangular bipyramid are connected by sharing angles. Based on the crystal structure of CaGa4O7, there are two different coordination environments of GaO4 triangular pyramid and CaO5 triangular bipyramid and oxygen vacancy defects. 2+ Different concentrations of Pb were introduced into the 2+ , forming different luminescent sites and defect types.

[0007] Preferably, after stopping the 254nm light source excitation, the afterglow color of the material is sky blue: when Pb 2+ When the doping amount is 0≤x≤0.0.5, the intensity and decay time of the afterglow decrease with the 2+ The doping amount increases; when Pb 2+ When the doping amount is 0.05≤x≤0.1, the intensity and decay time of the afterglow decrease with the 2+ The adjustable afterglow decay time can be used to create dynamic patterns that change over time, laying the foundation for dynamic anti-counterfeiting.

[0008] Preferably, the luminescence intensity of the material increases with the extension of the excitation time of the 254nm light source. The excitation time-dependent fluorescence property lays the foundation for the preparation of dynamically changing anti-counterfeiting patterns.

[0009] Preferably, when the material is irradiated with a 254nm light source, the intrinsic powder color of the powder gradually changes from white to brown; when irradiated with a 365nm light source, the brown color gradually bleaches to white, and the above-mentioned photochromic change is reversible.

[0010] The present invention also provides a method for preparing a self-activated long afterglow luminescent material with multi-mode luminescence, comprising the following steps:

[0011] (1) According to Ca 1-x Ga4O7:xPb 2+ The raw materials CaO, Ga2O3 and PbO are weighed in a stoichiometric ratio, and the molar ratio of CaO, Ga2O3 and PbO is 1-x:2:x, where x ranges from 0≤x≤0.1;

[0012] (2) Grind the weighed raw materials evenly;

[0013] (3) The ground raw material powder is transferred to a crucible, and sintered at 1300-1400° C. in air as a sintering atmosphere for 4-6 hours. After cooling, a self-activated long afterglow luminescent material is obtained.

[0014] The present invention also provides an application of a self-activated long afterglow material with multi-mode luminescence in information security, comprising the following steps:

[0015] Using CaGa4O7, Ca 0.95 Ga4O7:0.05Pb 2+ and Ca 0.9 Ga4O7:0.1Pb 2+ The three materials are processed into particles, and the obtained three particles are recorded as A, B, and C respectively. A, B, and C are used as pixels and arranged into a pixel matrix according to a preset method;

[0016] After irradiating the pixel array with 254nm ultraviolet light, the pixel array is placed in a dark environment. Among pixel points A, B, and C, pixel point C disappears quickly, resulting in pixel array pattern 1. Pixel array pattern 1 is used to store the first confidential information. After 180 seconds, pixel point A disappears next, resulting in pixel array pattern 2. Pixel array pattern 2 is used to store the second confidential information.

[0017] When the pixel matrix is ​​placed in a daylight environment, the colors of pixels A and B change from white to brown, obtaining pixel matrix pattern 3, which is used to store third confidential information; pixel matrix pattern 1, pixel matrix pattern 2, and pixel matrix pattern 3 are combined according to preset rules to achieve multiple information confidentiality.

[0018] The present invention also provides an application of a self-activated long afterglow material with multi-mode luminescence in product anti-counterfeiting, comprising the following steps:

[0019] Using CaGa4O7, Ca 0.95 Ga4O7:0.05Pb 2+ and Ca 0.9Ga4O7:0.1Pb 2+ The three materials were processed into coatings, and the three coatings obtained were marked as D, E, and F respectively;

[0020] An anti-counterfeiting pattern is provided on the product, wherein the anti-counterfeiting pattern includes three sub-patterns.

[0021] D, E, and F are applied to the three sub-patterns to obtain coated anti-counterfeiting patterns;

[0022] Irradiating the coated anti-counterfeiting pattern with 254nm ultraviolet light, the sub-patterns become brighter in the following preset order due to fluorescence enhancement: sub-pattern coated with F, sub-pattern coated with D, and sub-pattern coated with E;

[0023] Remove the 254nm ultraviolet light irradiation, and place the coated anti-counterfeiting pattern in a dark environment. The sub-patterns will darken in the following preset order due to the long afterglow effect: sub-pattern coated with F, sub-pattern coated with E, and sub-pattern coated with D. The product anti-counterfeiting is performed by brightening and darkening in the preset order.

[0024] Beneficial effects of the present invention:

[0025] Compared with the prior art, the present invention has the following advantages: 2+ A multi-mode, self-activated, long-lasting luminescence material was synthesized by doping and high-temperature solid-phase methods. By manipulating the concentration and depth of defect states in the CGO matrix, the phosphor's multi-mode optical properties, including afterglow intensity and decay time, photochromism, and excitation-time-dependent fluorescence, were effectively controlled. This combination of multi-mode optical properties overcomes the single-mode limitations of traditional encryption and anti-counterfeiting technologies, enabling applications in fields such as information encryption and anti-counterfeiting. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is Ca 1-x Ga4O7:xPb 2+ XRD pattern of

[0027] Figure 2 The diffuse reflectance spectra and photos of CaGa4O7 material after irradiation with 254nm ultraviolet light for different times; in the accompanying drawings of the present invention, Ca 1-x Ga4O7:xPb 2+ Phosphor is abbreviated as CGO:xPb 2+ ;

[0028] Figure 3 The excitation time-dependent fluorescence spectrum and afterglow spectrum of CaGa4O7 material and the corresponding luminescence photograph;

[0029] Figure 4 Ca0.95 Ga4O7:0.05Pb 2+ Excitation time-dependent fluorescence spectra and afterglow spectra of materials and corresponding luminescence photographs;

[0030] Figure 5 It is Ca 0.9 Ga4O7:0.1Pb 2+ Diffuse reflectance spectra and photos of the material after being irradiated with 254nm UV light for different times;

[0031] Figure 6 is Ca 0.9 Ga4O7:0.1Pb 2+ Excitation time-dependent fluorescence spectra and afterglow spectra of materials and corresponding luminescence photographs;

[0032] Figure 7 This is a schematic diagram of digital anti-counterfeiting technology made using three materials;

[0033] Figure 8 This is a schematic diagram of anti-counterfeiting technology using three materials to prepare a rose pattern;

[0034] Figure 9 It is a schematic diagram of information encryption application prepared using three materials; DETAILED DESCRIPTION

[0035] The present invention discloses a self-activated long afterglow material Ca with multi-mode luminescence 1-x Ga4O7:xPb 2+ The preparation method and application of the invention comprise the following steps:

[0036] (1) CaO, Ga2O3 and PbO with a purity greater than 99.9% are weighed according to a stoichiometric ratio, wherein the molar ratio of the materials is 1-x:2:x, and the molar ratio of x is in the range of 0-0.1;

[0037] (2) The weighed samples were mixed and placed in an agate mortar. 5-10 ml of anhydrous ethanol was added and then ground for 5-10 minutes.

[0038] (3) The ground powder is transferred to an alumina crucible, and then sintered in a high-temperature muffle furnace at 1300-1400°C with air as the sintering atmosphere for 4-6 hours. After naturally cooling to room temperature, a self-activated long afterglow material with multi-mode luminescence is obtained.

[0039] (4) Prepared Ca 1-x Ga4O7:xPb 2+ After being ground into powder, it is mixed with epoxy resin glue and prepared into patterns through screen printing and other methods. The differences in multi-mode optical properties are used for information encryption and anti-counterfeiting applications.

[0040] CaGa4O7 belongs to the monoclinic C2 / c space group and is composed of Ga 3+ Site and Ca 2+ The sites are respectively associated with 4 and 5 O 2- The atoms combine to form GaO4 triangular pyramid and CaO5 triangular bipyramid, which are connected by sharing angles. 1- x Ga4O7:xPb 2+ Based on the existence of two different coordination environments and abundant oxygen vacancy defects in the CaGa4O7 crystal structure, rare earth ions or transition metal ions are introduced at the A or B site to form a variety of different luminescent sites and defect types, further enriching the luminescent properties of the material and laying the foundation for achieving multi-mode dynamic luminescence.

[0041] The present invention will be further described below with reference to the examples.

[0042] Example 1

[0043] A preparation method and application of a self-activated long afterglow material CaGa4O7 with multi-mode luminescence, comprising the following steps:

[0044] (1) Weighing CaO and Ga2O3 with a purity greater than 99.9% according to a stoichiometric ratio, wherein the molar ratio of the materials is 1:2;

[0045] (2) The weighed samples were mixed and placed in an agate mortar, 5 ml of anhydrous ethanol was added, and then ground for 10 minutes;

[0046] (3) The ground powder was transferred to an alumina crucible and then sintered in a high-temperature muffle furnace at 1350°C with air as the sintering atmosphere for 4 hours. After naturally cooling to room temperature, a self-activated long-afterglow material with multi-mode luminescence was obtained.

[0047] The XRD test results of CaGa4O7 are as follows Figure 1 As shown, compared with the CaGa4O7 standard card, no obvious impurity peaks and phase changes were observed, proving that the material prepared in Example 1 was pure phase.

[0048] The photochromic curve of CaGa4O7 is as follows Figure 2 As shown, under 254nm light source, the color of the powder gradually changes from white to brown, and under 365nm light source, the brown gradually bleaches to white, which has the characteristics of recycling.

[0049] The excitation time-dependent fluorescence spectrum and afterglow spectrum of CaGa4O7 are as follows Figure 3 As shown in the figure, the luminescence intensity of the material increases with the extension of the excitation time of the 254nm light source, and there is a sky blue afterglow phenomenon after the excitation stops.

[0050] Example 2

[0051] A self-activated long-lasting glow material Ca with multi-mode luminescence 0.95 Ga4O7:0.05Pb 2+ The preparation method and application of the invention comprise the following steps:

[0052] (1) CaO, Ga2O3 and PbO with a purity greater than 99.9% were weighed according to a stoichiometric ratio, wherein the molar ratio of the materials was 0.95:2:0.05;

[0053] (2) The weighed samples were mixed and placed in an agate mortar, 5 ml of anhydrous ethanol was added, and then ground for 10 minutes;

[0054] (3) The ground powder was transferred to an alumina crucible and then sintered in a high-temperature muffle furnace at 1350°C with air as the sintering atmosphere for 4 hours. After naturally cooling to room temperature, a self-activated long-afterglow material with multi-mode luminescence was obtained.

[0055] Ca 0.95 Ga4O7:0.05Pb 2+ The XRD test results are as follows Figure 1 As shown, compared with the CaGa4O7 standard card, no obvious impurity peaks and phase changes were observed, proving that the material prepared in Example 2 was pure phase.

[0056] Ca 0.95 Ga4O7:0.05Pb 2+ The excitation time-dependent fluorescence spectrum and afterglow spectrum are as follows Figure 4 As shown, the luminous intensity of the material increases with the extension of the excitation time of the 254nm light source, and the rate of increase is faster than that of CaGa4O7 in Example 1. At the same time, the afterglow performance is improved compared with CaGa4O7.

[0057] Example 3

[0058] A self-activated long-lasting glow material Ca with multi-mode luminescence 0.9 Ga4O7:0.1Pb 2+ The preparation method and application of the invention comprise the following steps:

[0059] (1) CaO, Ga2O3 and PbO with a purity greater than 99.9% were weighed according to a stoichiometric ratio, wherein the molar ratio of the materials was 0.9:2:0.1;

[0060] (2) The weighed samples were mixed and placed in an agate mortar, 5 ml of anhydrous ethanol was added, and then ground for 10 minutes;

[0061] (3) The ground powder was transferred to an alumina crucible and then sintered in a high-temperature muffle furnace at 1350°C with air as the sintering atmosphere for 4 hours. After naturally cooling to room temperature, a self-activated long-afterglow material with multi-mode luminescence was obtained.

[0062] Ca 0.9 Ga4O7:0.1Pb 2+ The XRD test results are as follows Figure 1 As shown, compared with the CaGa4O7 standard card, no obvious impurity peaks and phase changes were observed, proving that the material prepared in Example 3 was pure phase.

[0063] Ca 0.9 Ga4O7:0.1Pb 2+ The photochromic curve of Figure 5 As shown in Figure 1, under 254nm light source, the diffuse reflectance curve of the material did not change significantly and the powder remained white.

[0064] Ca 0.9 Ga4O7:0.1Pb 2+ The excitation time-dependent fluorescence spectrum and afterglow spectrum are as follows Figure 6 As shown, the excitation time-dependent fluorescence spectrum of the material shows that Ca 0.9 Ga4O7:0.1Pb 2+ The change process of is faster than that of the materials in Examples 1 and 2. However, the afterglow performance of the material is significantly reduced.

[0065] Example 4

[0066] An application of a self-activated long afterglow material with multi-mode luminescence in information security includes the following steps:

[0067] like Figure 7 As shown, the materials obtained in Examples 1, 2 and 3 are fully ground and added to circular containers respectively, and the circular containers containing the three materials are arranged in a dot matrix as shown in the schematic diagram. The prepared "888" pattern undergoes photochromic change after being irradiated by a 254nm ultraviolet lamp in a daylight environment, and "888" changes to "906", obtaining encrypted information 1. In a dark environment, after the obtained "888" pattern is irradiated by a 254nm ultraviolet lamp, "888" first changes to "906", obtaining encrypted information 2. After 180s, "906" changes to "475", obtaining encrypted information 3. By arranging and combining encrypted information 1, encrypted information 2, and encrypted information 3, more complex encrypted information can be obtained based on the dynamic changes in the dot matrix color. Therefore, by combining photochromic and long afterglow performance, the shortcomings of the single traditional long afterglow encryption mode are overcome, and dynamic multi-mode anti-counterfeiting technology is realized.

[0068] Example 5

[0069] An anti-counterfeiting application of a self-activated long-afterglow material with multi-mode luminescence, comprising the following steps:

[0070] like Figure 8 As shown, the materials obtained in Examples 1, 2 and 3 are fully ground and mixed with epoxy resin glue, and then the rose pattern shown in the schematic diagram is prepared by screen printing. In a dark environment, the "flower", "stem" and "leaf" parts of the rose pattern undergo fluorescence enhancement at different rates under the irradiation of a 254nm ultraviolet lamp, showing the leaves, flowers and stem parts in turn. After turning off the 254nm ultraviolet lamp, the leaves, stems and flowers of the rose pattern disappear in turn, thereby achieving real-time pattern changes. Patterns similar to the rose pattern in this embodiment can be combined with any non-anti-counterfeiting pattern on the surface of the product, and have a decorative effect in themselves. When used as an anti-counterfeiting label, it is not easy for counterfeiters to find anti-counterfeiting labels mixed with non-anti-counterfeiting patterns, which significantly increases the difficulty of counterfeiting and further increases the anti-counterfeiting effect of this anti-counterfeiting application, and has the application potential of dynamic anti-counterfeiting. Compared with the traditional single long afterglow encryption mode, the technical means in the present invention realize more modes of pattern change forms, forming a richer anti-counterfeiting pattern.

[0071] In addition, in the preparation formulas of Examples 1 to 3 of the present invention, by slightly changing the value of x and keeping the other preparation processes the same, self-activated long afterglow materials with different chemical formulas can be prepared and countless anti-counterfeiting pattern combinations can be printed.

[0072] Example 6

[0073] An information encryption application of a self-activated long afterglow material with multi-mode luminescence includes the following steps:

[0074] like Figure 9 As shown, the materials obtained in Examples 1, 2, and 3 were thoroughly ground and added to a circular container. The three materials were arranged as shown in the schematic diagram. In a dark environment, after irradiation with a 254nm UV lamp, the prepared matrix pattern first displayed a rightward arrow, indicating an error message. After 180 seconds, the arrow direction changed from rightward to leftward, indicating the correct message. Therefore, by utilizing the different afterglow properties of the materials, information encryption is achieved.

[0075] The foregoing description shows and describes several preferred embodiments of the invention. However, as previously stated, it should be understood that the invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Rather, the invention is applicable to various other combinations, modifications, and environments and is capable of modification within the scope of the inventive concept described herein, through the teachings above, or through techniques or knowledge in the relevant art. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the invention are intended to be within the scope of the appended claims.

Claims

1. A self-activated long-lasting luminescent material with multi-mode luminescence, characterized in that :The chemical formula is Ca 1-x Ga4O7:xPb 2+ where 0 <x≤0.1; The Ca 1-x Ga4O7:xPb 2+ Based on the monoclinic C2 / c space group of CaGa4O7, Ga 3+ Site and Ca 2+ The sites are respectively associated with 4 and 5 O 2- The atoms combine to form GaO4 triangular pyramid and CaO5 triangular bipyramid, and the GaO4 triangular pyramid and CaO5 triangular bipyramid are connected by sharing angles. Based on the crystal structure of CaGa4O7, there are two different coordination environments of GaO4 triangular pyramid and CaO5 triangular bipyramid and oxygen vacancy defects. 2+ Different concentrations of Pb were introduced into the 2+ , forming different luminescent sites and defect types.

2. The self-activated long afterglow luminescent material with multi-mode luminescence according to claim 1, characterized in that : The afterglow color of the self-activated long afterglow luminescent material is sky blue after being excited by a 254 nm light source: When the doping amount of Pb 2+ is 0 < x ≤ 0.05, the intensity and decay time of the afterglow increase with the increase of the doping amount of Pb 2+ ; when the doping amount of Pb 2+ is 0.05 ≤ x ≤ 0.1, the intensity and decay time of the afterglow decrease with the increase of the doping amount of Pb 2+ .

3. The self-activated long afterglow luminescent material with multi-mode luminescence according to claim 1, characterized in that :The luminescence intensity of the material increases with the extension of the excitation time of the 254nm light source.

4. The self-activated long afterglow luminescent material with multi-mode luminescence according to claim 1, characterized in that : When the material is irradiated with a 254nm light source, the intrinsic powder color of the powder gradually changes from white to brown; when irradiated with a 365nm light source, the brown color gradually bleaches to white, and the photochromic change is reversible.

5. A method for preparing a self-activated long-lasting luminescent material with multi-mode luminescence according to claim 1, characterized in that : Includes the following steps: (1) According to Ca 1-x Ga4O7:xPb 2+ The raw materials CaO, Ga2O3 and PbO are weighed in stoichiometric ratio. The molar ratio of CaO, Ga2O3 and PbO is 1-x:2:x, where x is 0 <x≤0.1; (2) Grind the weighed raw materials evenly; (3) The ground raw material powder is transferred to a crucible, and sintered at 1300-1400° C. in air as a sintering atmosphere for 4-6 hours. After cooling, a self-activated long afterglow luminescent material is obtained.

6. Application of a self-activated long afterglow material with multi-mode luminescence in information security, characterized in that: The following steps are involved: Using CaGa4O7, Ca 0.95 Ga4O7:0.05Pb 2+ and Ca 0.9 Ga4O7:0.1Pb 2+ The three materials are processed into particles, and the obtained three particles are recorded as A, B, and C respectively. A, B, and C are used as pixels and arranged into a pixel matrix according to a preset method; After irradiating the pixel array with 254nm ultraviolet light, the pixel array is placed in a dark environment. Among pixel points A, B, and C, pixel point C disappears quickly, resulting in pixel array pattern 1. Pixel array pattern 1 is used to store the first confidential information. After 180 seconds, pixel point A disappears next, resulting in pixel array pattern 2. Pixel array pattern 2 is used to store the second confidential information. When the pixel matrix is ​​placed in a daylight environment, the colors of pixels A and B change from white to brown, thereby obtaining pixel matrix pattern 3, wherein the pixel matrix pattern 3 is used to store the third confidential information; The pixel dot matrix pattern 1, the pixel dot matrix pattern 2 and the pixel dot matrix pattern 3 are combined according to a preset rule to realize multiple information confidentiality.

7. Application of a self-activated long afterglow material with multi-mode luminescence in product anti-counterfeiting, characterized in that: The following steps are involved: Using CaGa4O7, Ca 0.95 Ga4O7:0.05Pb 2+ and Ca 0.9 Ga4O7:0.1Pb 2+ The three materials were processed into coatings, and the three coatings obtained were marked as D, E, and F respectively; An anti-counterfeiting pattern is provided on the product, wherein the anti-counterfeiting pattern includes three sub-patterns. D, E, and F are respectively applied on the three sub-patterns to obtain coated anti-counterfeiting patterns; Irradiating the coated anti-counterfeiting pattern with 254nm ultraviolet light, the sub-patterns become brighter in the following preset order due to fluorescence enhancement: sub-pattern coated with F, sub-pattern coated with D, and sub-pattern coated with E; The 254 nm ultraviolet light irradiation is removed, and the coated anti-counterfeiting pattern is placed in a dark environment. The sub-patterns are darkened in the following preset order due to the long afterglow effect: the sub-pattern coated with F, the sub-pattern coated with E, and the sub-pattern coated with D. Product anti-counterfeiting through preset sequences of lightening and darkening.

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