Thermally-driven time-dependent dynamic multicolor fluorescent material and preparation method thereof, thermally-driven time-dependent dynamic multicolor fluorescent anti-counterfeiting four-dimensional code material and preparation method and application of thermally-driven time-dependent dynamic multicolor fluorescent anti-counterfeiting four-dimensional code material

Abstract

The invention belongs to the technical field of information anti-counterfeiting, and particularly relates to a thermally-driven time-dependent dynamic multicolor fluorescent material and a preparation method thereof, and a thermally-driven time-dependent dynamic multicolor fluorescent anti-counterfeiting four-dimensional code material and a preparation method and application thereof. The chemical composition of the thermally-driven time-dependent dynamic multicolor fluorescent material provided by the invention is Ba (1-x) K0. 05Eu0. 02MgSiO4, wherein x is more than 0 and less than or equal to 0.1. The thermally-driven time-dependent dynamic multicolor fluorescent material has a dynamic multicolor fluorescence emission characteristic in a heating state, can discriminate the authenticity of information, and has high-level information storage and anti-counterfeiting capabilities.

Description

Technical Field

[0001] The present invention belongs to the technical field of information anti-counterfeiting, and specifically relates to a thermally driven time-dependent dynamic multi-color fluorescent material and a preparation method thereof, a thermally driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material and a preparation method and application thereof. Background Art

[0002] The popularity of the Internet and the rapid development of 5G and 6G communication technologies have resulted in the generation of hundreds of millions of pieces of information every day. These pieces of information are disseminated and circulated through the Internet and various communication devices. In the process of obtaining, transmitting and receiving information, there are often incidents of false information, information theft, information cracking, and information replacement. With the surge in the amount of information, information security issues have become increasingly prominent, and effective measures are urgently needed to address them.

[0003] To ensure information security, more and more researchers have proposed a large number of information anti-counterfeiting measures, such as using optical image coding technology to add anti-counterfeiting labels, electronic anti-counterfeiting labels, barcodes, QR codes and chip anti-counterfeiting and other information anti-counterfeiting methods. However, the previous information anti-counterfeiting methods were independent of the information and had poor concealment. They were easily cracked, resulting in consequences such as information leakage, replacement, and loss. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a thermally driven time-dependent dynamic multi-color fluorescent material and a preparation method thereof, a thermally driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material and a preparation method and application thereof. The thermally driven time-dependent dynamic multi-color fluorescent material has dynamic multi-color fluorescent emission characteristics under heating, can distinguish the authenticity of information, and has a high level of information storage and anti-counterfeiting capabilities.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a thermally driven time-dependent dynamic multi-color fluorescent material, the chemical composition of which is: Ba 1- x K 0.05 Eu 0.02 MgSiO4, 0<x≤0.1.

[0007] Preferably, 0<x≤0.07.

[0008] The present invention also provides a method for preparing the heat-driven time-dependent dynamic multicolor fluorescent material described in the above technical solution, comprising the following steps:

[0009] According to the stoichiometric ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, BaCO3, K2CO3, Eu2O3, MgO and SiO2 are mixed and wet-milled, and the obtained ball-milled slurry is dried and then first sintered in air to obtain a first sintered material;

[0010] The first sintered material is crushed and then pressed, and the obtained pressed body is subjected to a second sintering in a reducing atmosphere to obtain the thermally driven time-dependent dynamic multi-color fluorescent material.

[0011] Preferably, the temperature of the first sintering is 900-1100° C.; the time of the first sintering is 2-6 hours; the reducing atmosphere is hydrogen or carbon monoxide; the temperature of the second sintering is 1100-1300° C.; the time of the second sintering is 2-6 hours.

[0012] The present invention also provides a thermally driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material, the preparation raw materials include thermally driven time-dependent dynamic multi-color fluorescent material, polydimethylsiloxane, polydimethylsiloxane curing agent and softener;

[0013] The thermally driven time-dependent dynamic multi-color fluorescent material is the thermally driven time-dependent dynamic multi-color fluorescent material described in the above technical solution or the thermally driven time-dependent dynamic multi-color fluorescent material prepared by the preparation method described in the above technical solution.

[0014] Preferably, the polydimethylsiloxane and the polydimethylsiloxane curing agent are two-component Dow Corning DC184 silicone rubber; and the softener is a silicone oil substance.

[0015] Preferably, the mass ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, polydimethylsiloxane, polydimethylsiloxane curing agent and softener is 20-40:10-20:1-2:1-2.

[0016] The present invention also provides a method for preparing the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material described in the above technical scheme, comprising the following steps: mixing the heat-driven time-dependent dynamic multi-color fluorescent material, polydimethylsiloxane, a polydimethylsiloxane curing agent and a softener, placing the obtained mixed mucus in a mold, and demolding after drying to obtain the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material.

[0017] The present invention also provides the application of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material described in the above technical scheme or the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material prepared by the preparation method described in the above technical scheme in information anti-counterfeiting.

[0018] The present invention also provides a heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code, including a charged heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material;

[0019] The heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material is the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material described in the above technical solution or the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material prepared by the preparation method described in the above technical solution.

[0020] The present invention provides a thermally driven time-dependent dynamic multi-color fluorescent material, the chemical composition of which is: Ba 1- x K 0.05 Eu 0.02 MgSiO4, 0<x≤0.1. The heat-driven time-dependent dynamic multi-color fluorescent material provided by the present invention can release fluorescent signals in a heated state, and information can be read by collecting fluorescent characteristics (such as luminous color, luminous intensity, and its dynamic changes with thermal driving time). The color and intensity of fluorescence during heating emission can be used as information, and the difference in color and intensity can be identified by the naked eye. As the heating time increases, the color of the emitted fluorescence changes. The change in heating time is accompanied by the degree of absorption of thermal energy by the heat-driven time-dependent dynamic multi-color fluorescent material. As the absorbed energy increases, electrons trapped in deep energy levels will be released, thereby showing a different fluorescence color from that emitted when shallow energy level electrons are released. The present invention utilizes the dynamic multi-color fluorescence emission characteristics of the heat-driven time-dependent dynamic multi-color fluorescent material in a heated state, which can distinguish the authenticity of information and has a high level of information storage and anti-counterfeiting capabilities.

[0021] The current anti-counterfeiting technologies, such as anti-counterfeiting labels, electronic anti-counterfeiting labels, barcodes, QR codes and anti-counterfeiting chips, all store anti-counterfeiting information in these labels, but do not carry the information to be transmitted; in comparison, the heat-driven time-dependent dynamic multi-color fluorescent material provided by the present invention can emit dynamic multi-color fluorescence, integrate information and anti-counterfeiting information, and read it by heating. The information carried by the carrier with dynamic multi-color fluorescence emission characteristics is real information, and the information carried by other carriers that do not have this feature is interference, thereby achieving a high level of information anti-counterfeiting and opening up new ideas for information anti-counterfeiting technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Physical photographs of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional codes prepared in Example 1, Example 2, and Example 4, and physical photographs of the composite anti-counterfeiting four-dimensional code composed of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional codes prepared in Example 1, 2, and 4 under dark conditions;

[0023] Figure 2 X-ray diffraction patterns of the heat-driven time-dependent dynamic multicolor fluorescent materials prepared in Examples 1 to 5 and Comparative Example 1;

[0024] Figure 3 This is a transmission electron microscopy element distribution (EDS) image of the heat-driven time-dependent dynamic multicolor fluorescent material prepared in Example 4;

[0025] Figure 4 The thermally driven dynamic fluorescence emission spectra of the thermally driven time-dependent dynamic multicolor fluorescent materials prepared in Examples 1 to 5 and Comparative Example 1;

[0026] Figure 5 This is a chromaticity diagram of the dynamic multicolor fluorescence emission colors of the heat-driven time-dependent dynamic multicolor fluorescent material prepared in Example 4. DETAILED DESCRIPTION

[0027] The present invention provides a thermally driven time-dependent dynamic multi-color fluorescent material, the chemical composition of which is: Ba 1- x K 0.05 Eu 0.02 MgSiO4, 0<x≤0.1.

[0028] Unless otherwise specified, the present invention has no special requirements on the sources of the raw materials used, and commercially available products known to those skilled in the art may be used.

[0029] As an embodiment, the chemical composition of the thermally driven time-dependent dynamic multicolor fluorescent material is Ba 1- x K 0.05 Eu 0.02 MgSiO4, 0<x≤0.07, in specific embodiments, x=0.02, 0.025, 0.03, 0.05 or 0.07.

[0030] Ba, Mg, Si, and O elements are the components of the thermally driven time-dependent dynamic multi-color fluorescent material. The lack of any one of them will cause its collapse. The K element plays a role in increasing the internal defect concentration of the thermally driven time-dependent dynamic multi-color fluorescent material. The role of the Eu element is to give the thermally driven time-dependent dynamic multi-color fluorescent material luminescence characteristics.

[0031] As an implementation mode, the heat-driven time-dependent dynamic multi-color fluorescent material has a hexagonal phase structure.

[0032] As an implementation mode, the luminescence wavelength of the heat-driven time-dependent dynamic multicolor fluorescent material is 350 to 800 nm; the luminescence color is bluish purple, or a superposition of green and bluish purple; and the luminescence duration is 0.3 to 4 s.

[0033] The heat-driven time-dependent dynamic multi-color fluorescent material provided by the present invention can release fluorescent signals in a heated state, and information can be read by collecting fluorescent characteristics (such as luminous color, luminous intensity, and its dynamic changes with heat-driven time). The color and intensity of the fluorescence during heating emission can be used as information, and the difference in color and intensity can be identified by the naked eye. As the heating time increases, the color of the emitted fluorescence changes. The change in heating time is accompanied by the degree of absorption of thermal energy by the heat-driven time-dependent dynamic multi-color fluorescent material. As the absorbed energy increases, the electrons trapped in the deep energy level will be released, thereby showing a different performance from the fluorescence color emitted when the shallow energy level electrons are released. The present invention utilizes the dynamic multi-color fluorescence emission characteristics of the heat-driven time-dependent dynamic multi-color fluorescent material in a heated state, which can distinguish the authenticity of information and has a high level of information storage and anti-counterfeiting capabilities. The current anti-counterfeiting technologies, such as anti-counterfeiting labels, electronic anti-counterfeiting labels, barcodes, QR codes and anti-counterfeiting chips, all store anti-counterfeiting information in these labels, but do not carry the information to be transmitted; in comparison, the heat-driven time-dependent dynamic multi-color fluorescent material provided by the present invention can emit dynamic multi-color fluorescence in a heated state, integrate information and anti-counterfeiting information, and read it by heating. The information carried by the carrier with dynamic multi-color fluorescence emission characteristics is real information, and the information carried by other carriers that do not have this feature is interference, thereby achieving a high level of information anti-counterfeiting.

[0034] The present invention also provides a method for preparing the heat-driven time-dependent dynamic multicolor fluorescent material described in the above technical solution, comprising the following steps:

[0035] According to the stoichiometric ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, BaCO3, K2CO3, Eu2O3, MgO and SiO2 are mixed and wet-milled, and the obtained ball-milled slurry is dried and then first sintered in air to obtain a first sintered material;

[0036] The first sintered material is crushed and then pressed, and the obtained pressed body is subjected to a second sintering in a reducing atmosphere to obtain the thermally driven time-dependent dynamic multi-color fluorescent material.

[0037] According to the stoichiometric ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, the present invention mixes BaCO3, K2CO3, Eu2O3, MgO and SiO2 and performs wet ball milling to obtain ball milling slurry.

[0038] As an implementation mode, the BaCO3, K2CO3, Eu2O3, MgO, and SiO2 are all micron-sized powders.

[0039] As an implementation mode, the reagent used for the wet ball milling is anhydrous ethanol or distilled water, and in the specific embodiment, it is anhydrous ethanol; the solid-liquid ratio of the wet ball milling is 1:5-8, and in the specific embodiment, it is 1:5-6; the rotation speed of the wet ball milling is 20-30 Hz, and in the specific embodiment, it is 22-28 Hz; the time of the wet ball milling is 18-30 hours, and in the specific embodiment, it is 20-26 hours; the material of the grinding balls used in the wet ball milling is agate or zirconia, and in the specific embodiment, it is agate; the grinding balls used in the wet ball milling include grinding balls of various sizes and diameters, among which the maximum ball diameter does not exceed 1 cm; the particle size of the solids in the ball milling slurry obtained by the wet ball milling is 200-300 mesh, and in the specific embodiment, it is 250-300 mesh.

[0040] After obtaining the ball-milled slurry, the present invention dries the ball-milled slurry and then performs a first sintering in air to obtain a first sintered material.

[0041] As an implementation mode, the drying temperature is 50-130° C., and in a specific embodiment, it is 100-120° C.; the drying time is 0.3-3.5 h, and in a specific embodiment, it is 0.5-2 h.

[0042] As an implementation manner, the temperature of the first sintering is 900-1100° C., and in a specific embodiment, it is 950-1050° C.; the time of the first sintering is 2-6 hours, and in a specific embodiment, it is 3-5 hours.

[0043] In the first sintering process, a mixture of BaCO3, K2CO3, Eu2O3, MgO and SiO2 is melted, fused and then cooled to obtain a heat-driven time-dependent dynamic multi-color fluorescent material.

[0044] After obtaining the first sintered material, the present invention crushes the first sintered material and then presses it, and the obtained pressed body is subjected to a second sintering in a reducing atmosphere to obtain the thermally driven time-dependent dynamic multi-color fluorescent material.

[0045] As an implementation mode, the crushing is grinding or pulverizing, and in a specific embodiment, it is grinding; the crushing to a particle size of 200-300 mesh, and in a specific embodiment, it is 250-300 mesh; the pressing pressure is 7-12 MPa, and in a specific embodiment, it is 8-11 MPa; the holding time of the pressing is 0.5-1.5 min, and in a specific embodiment, it is 0.8-1.2 min; the pressing is tabletting; the pressed body is a sheet-like body.

[0046] As an embodiment, the reducing atmosphere is hydrogen or carbon monoxide, and in the specific embodiment, it is hydrogen; the temperature of the second sintering is 1100-1300°C, and in the specific embodiment, it is 1150-1250°C; the time of the second sintering is 2-6h, and in the specific embodiment, it is 3-5h.

[0047] In the second sintering process, the heat-driven time-dependent dynamic multi-color fluorescent material is fired into porcelain to produce a ceramic sheet.

[0048] The present invention also provides a thermally driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material, the preparation raw materials include thermally driven time-dependent dynamic multi-color fluorescent material, polydimethylsiloxane, polydimethylsiloxane curing agent and softener;

[0049] The thermally driven time-dependent dynamic multi-color fluorescent material is the thermally driven time-dependent dynamic multi-color fluorescent material described in the above technical solution or the thermally driven time-dependent dynamic multi-color fluorescent material prepared by the preparation method described in the above technical solution.

[0050] As an implementation method, the polydimethylsiloxane and the polydimethylsiloxane curing agent are two-component Dow Corning DC184 silicone rubber, wherein the polydimethylsiloxane corresponds to component A of Dow Corning DC184 silicone rubber, and the polydimethylsiloxane curing agent corresponds to component B of Dow Corning DC184 silicone rubber; the softener is a silicone oil substance; the silicone oil substance includes one or more of methyl silicone oil, ethyl silicone oil and dimethyl silicone oil, and in a specific embodiment, it is methyl silicone oil. The present invention effectively improves the flexibility of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material by adding a softener.

[0051] As an implementation mode, the mass ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, polydimethylsiloxane, polydimethylsiloxane curing agent and softener is 20-40:10-20:1-2:1-2, and in a specific embodiment, it is 25-35:10-15:1-2:1-2.

[0052] The present invention also provides a method for preparing the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material according to the above technical solution, comprising the following steps:

[0053] The heat-driven time-dependent dynamic multi-color fluorescent material, polydimethylsiloxane, a polydimethylsiloxane curing agent and a softener are mixed, and the obtained mixed mucus is placed in a mold, and the mold is demolded after drying to obtain the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material.

[0054] As an embodiment, before the mixing, it also includes: crushing and then screening the heat-driven time-dependent dynamic multi-color fluorescent material; the crushing is grinding; the aperture of the sieve used for the screening is 300-700 mesh, and in a specific embodiment, it is 400-600 mesh.

[0055] As an embodiment, the mixing is performed under stirring conditions; the stirring rate is 50 to 80 rpm, and in a specific embodiment, it is 60 to 70 rpm; the stirring time is 5 to 10 min, and in a specific embodiment, it is 6 to 8 min.

[0056] The present invention has no special limitation on the material and size of the mold, which can be determined according to actual needs.

[0057] As an implementation mode, the drying temperature is 50-130° C., and in a specific embodiment, it is 100-120° C.; the drying time is 0.3-3.5 h, and in a specific embodiment, it is 0.5-2 h.

[0058] As an implementation manner, the thickness of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material is 0.3 to 1.2 mm, and in a specific embodiment, it is 0.5 to 1 mm.

[0059] The present invention also provides the application of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material described in the above technical scheme or the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material prepared by the preparation method described in the above technical scheme in information anti-counterfeiting.

[0060] The present invention also provides a heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code, including a charged heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material;

[0061] The heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material is the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material described in the above technical solution or the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material prepared by the preparation method described in the above technical solution.

[0062] As an embodiment, the method for preparing the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code comprises the following steps:

[0063] The heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material is charged to obtain the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code.

[0064] As an implementation mode, the charging is to use ultraviolet light to irradiate the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material: the wavelength of the ultraviolet light is 254nm or 365nm or 405nm, and it is 254nm in the specific embodiment; the irradiation time is 1 to 5min, and it is 2 to 4min in the specific embodiment; the ultraviolet light is provided by an ultraviolet lamp, and the irradiation power of the ultraviolet light is 10 to 20W, and it is 10W in the specific embodiment.

[0065] The present invention irradiates a heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material with ultraviolet light. After irradiation, the energy of the ultraviolet light is stored in the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material, that is, information is written to obtain a heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code.

[0066] As an embodiment, the identification method of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code is: heating the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code to release a fluorescent signal, and reading the fluorescent signal with the naked eye or a mobile phone.

[0067] As an implementation mode, the heating temperature is 240-250° C., and in a specific embodiment, it is 250° C. The present invention has no special limitation on the heating time.

[0068] The heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code provided by the present invention releases a fluorescent signal by heating, collects fluorescent characteristics, and realizes information reading. During heating emission, the fluorescence color and intensity can be used as information, and the difference in color and intensity can be identified by the naked eye. The actual use process can be read by the naked eye or a mobile phone. As the heating time increases, the color of the four-dimensional code changes. The change in heating time is accompanied by the degree of absorption of thermal energy by the four-dimensional code. As the absorbed energy increases, the electrons trapped in the deep energy level will be released, thereby showing a different performance from the fluorescent color emitted when the shallow energy level electrons are released. By identifying the characteristics of the fluorescence emitted by the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code (such as luminous color, luminous intensity, and its dynamic change with the heat-driven time), the information is read to realize the integration of information and anti-counterfeiting. The information carried by the carrier with dynamic multi-color fluorescent emission characteristics is true information, and the information carried by other carriers that do not have this feature is interference, thereby realizing high-level information anti-counterfeiting.

[0069] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, but they should not be construed as limiting the protection scope of the present invention.

[0070] Example 1

[0071] (1) The chemical composition of the thermally driven time-dependent dynamic multicolor fluorescent material is: Ba 0.93 K 0.05 Eu 0.02 MgSiO4, x = 0.07, the preparation process is as follows:

[0072] According to the stoichiometric ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, BaCO3, K2CO3, Eu2O3, MgO, and SiO2 are mixed and wet-milled, the reagent used for ball milling is anhydrous ethanol, the solid-liquid ratio is 1:5, the speed of the ball milling is 25 Hz, the time is 24 h, the material of the grinding balls used is agate, and the grinding balls are grinding balls of various sizes and diameters, wherein the maximum ball diameter does not exceed 1 cm, to obtain a ball milling slurry, and the particle size of the solid in the obtained ball milling slurry is 250 mesh;

[0073] The ball-milled slurry was dried at 105° C. for 2 h, and then subjected to a first sintering in air at a temperature of 1000° C. for 5 h to obtain a first sintered material;

[0074] The first sintered material is crushed to a particle size of 250 mesh, and tabletted at 10 MPa. The obtained sheet body is subjected to a second sintering in a hydrogen reducing atmosphere at a temperature of 1200° C. for 5 hours to obtain the thermally driven time-dependent dynamic multi-color fluorescent material;

[0075] (2) The preparation method of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material is as follows:

[0076] The above-mentioned heat-driven time-dependent dynamic multi-color fluorescent material was ground and sieved with a 500-mesh sieve. The obtained powder was mixed with two-component Dow Corning DC184 silicone rubber (polydimethylsiloxane corresponds to component A of Dow Corning DC184 silicone rubber, polydimethylsiloxane curing agent corresponds to component B of Dow Corning DC184 silicone rubber, and the mass ratio of component A to component B is 10:1) and methyl silicone oil in a mass ratio of 20:11:1 and stirred at 70 rpm for 8 minutes. The obtained mixed viscous liquid was placed in a mold and demolded after drying at 100°C for 3 hours to obtain a heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material with a thickness of 1 mm.

[0077] (3) The preparation method of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code is as follows:

[0078] The above-mentioned heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material is irradiated with ultraviolet light, the wavelength of the ultraviolet light is 254nm, the irradiation time is 2min, the ultraviolet light is provided by an ultraviolet lamp, and the power is 10W, that is, information is written into the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material to obtain the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code.

[0079] Example 2

[0080] The difference from Example 1 is that the chemical composition of the thermally driven time-dependent dynamic multi-color fluorescent material is: Ba 0.95 K 0.05 Eu 0.02 MgSiO4, x=0.05, other contents are the same as in Example 1.

[0081] Example 3

[0082] The difference from Example 1 is that the chemical composition of the thermally driven time-dependent dynamic multi-color fluorescent material is: Ba 0.97 K 0.05 Eu 0.02 MgSiO4, x=0.03, other contents are the same as in Example 1.

[0083] Example 4

[0084] The difference from Example 1 is that the chemical composition of the thermally driven time-dependent dynamic multi-color fluorescent material is: Ba 0.975 K 0.05 Eu 0.02 MgSiO4, x=0.025, other contents are the same as in Example 1.

[0085] Example 5

[0086] The difference from Example 1 is that the chemical composition of the thermally driven time-dependent dynamic multi-color fluorescent material is: Ba 0.98 K 0.05 Eu 0.02 MgSiO4, x=0.02, and the rest is the same as in Example 1.

[0087] Comparative Example 1

[0088] The difference from Example 1 is that the chemical composition of the thermally driven time-dependent dynamic multi-color fluorescent material is: BaK 0.05 Eu 0.02 MgSiO4, x=0, and the rest of the contents are the same as in Example 1.

[0089] Performance Testing

[0090] (1) Figure 1 The actual photographs of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional codes prepared in Example 1, Example 2, and Example 4 ((a), (b), and (c), with an actual size of 1cm×1cm×1mm) and the actual photograph (d) of the composite anti-counterfeiting four-dimensional code composed of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional codes prepared in Examples 1, 2, and 4 under dark conditions, are Example 4, Example 2, and Example 1, respectively.

[0091] Depend on Figure 1 It can be seen that after being charged with ultraviolet light (254nm) for 2 minutes, under the heating state of 250°C, different embodiments show different luminescence characteristics as the heating time increases. The composite anti-counterfeiting four-dimensional code composed of heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code has a luminescence duration of 4s.

[0092] (2) X-ray diffraction experiments were performed on the heat-driven time-dependent dynamic multicolor fluorescent materials prepared in Examples 1 to 5 and Comparative Example 1. The obtained X-ray diffraction patterns at diffraction angles of 10 to 70° were as follows: Figure 2 shown.

[0093] Depend on Figure 2 It can be seen that all the diffraction peaks of the heat-driven time-dependent dynamic multicolor fluorescent materials prepared in Examples 1 to 5 and Comparative Example 1 correspond well to the standard card BaMgSiO4 (PDF#16-0573), and there is no obvious second phase, indicating that the synthesized samples are pure phase substances. Compared with the standard card, it is found that the six samples all belong to the hexagonal phase structure, indicating that the change of Ba content will not affect the phase structure of the crystal. Figure 2 Analysis revealed that with the change of Ba content, the main diffraction peak position corresponding to the crystal plane (102) of the six samples did not move significantly, indicating that the change of Ba content will not have a significant effect on the crystal volume.

[0094] (3) Figure 3 This is a transmission electron microscopy element distribution (EDS) diagram of the heat-driven time-dependent dynamic multicolor fluorescent material prepared in Example 4, where (a) shows: a square area of ​​approximately 250nm×250nm was selected for transmission electron microscopy element distribution analysis, and (b), (c), (d), (e), (f), and (g) are the distribution of O, K, Mg, Si, Ba, and Eu elements in the selected area of ​​the sample, respectively.

[0095] Depend on Figure 3 It can be seen that the six elements, O, K, Mg, Si, Ba and Eu, are evenly distributed in the selected area without element segregation, indicating that the six elements have successfully participated in crystallization and phase formation; according to the chemical composition, the content of Eu and K is relatively small, but through the analysis of the test results, it is known that the amount of content will not have a significant impact on the distribution.

[0096] Depend on Figure 3 The element distribution and Figure 2 The X-ray diffraction experimental results show that the present invention successfully achieves the synthesis of thermally driven time-dependent dynamic multicolor fluorescent materials through a solid phase method.

[0097] (4) A thermally driven fluorescence emission experiment was conducted on the heat-driven time-dependent dynamic multicolor fluorescent materials (in the form of discs) prepared in Examples 1 to 5 and Comparative Example 1, and the heat-driven dynamic fluorescence emission spectra corresponding to Examples 1 to 5 and Comparative Example 1 were collected. The specific process was to charge the heat-driven time-dependent dynamic multicolor fluorescent materials in the form of discs with ultraviolet light (254 nm) for 2 minutes, and then collect the heat-driven dynamic fluorescence emission spectra with a duration of 3.9 seconds under a heating state of 250° C. The results Figure 4 As shown, (a), (b), (c), (d), (e), and (f) correspond to the thermally driven dynamic fluorescence emission spectra of Examples 1 to 5 and Comparative Example 1, respectively, with a wavelength range of 350 to 800 nm. There are 13 curves in each figure, and the order of line colors is: black, red, green, blue, cyan, magenta, dark yellow, navy blue, purple, wine red, olive green, dark cyan, and royal blue, corresponding to the fluorescence emission spectra at different times, respectively. Each line represents the fluorescence emission spectrum at different heating times, and the corresponding order is: 300, 600, 900, 1200, 1500, 1800, 2100, 2400, 2700, 3000, 3300, 3600, and 3900, in milliseconds, and the time interval between every two lines is 300 milliseconds.

[0098] like Figure 4 As shown in (a), the fluorescence emission color of Example 1 is mainly concentrated in the blue-violet light range, and the main emission peak is located near 400nm. After preheating for 300 milliseconds at 250°C, the sample emits blue-violet light. As the heating time increases, the blue-violet light intensity of the sample gradually increases until it reaches a maximum value at 1200 milliseconds. After 1200 milliseconds, as the heating time increases, the blue-violet light intensity emitted by the sample gradually decreases until the matrix emits weak light, and the entire thermally driven fluorescence emission process ends.

[0099] Similarly Figure 4 As shown in (b), (c) and (e), the fluorescence emission colors of Examples 2, 3 and 5 are mainly superimposed colors of green light and blue-violet light, and the emission peaks are located near 400nm and 500nm. Because the intensity of green light is significantly stronger than that of blue-violet light, the superimposed color is obviously cyan. After 300 milliseconds of preheating, cyan light is emitted. Similarly, as the heating time increases, the cyan light intensity of the sample gradually increases. However, the duration of the increase in luminous intensity of the three examples is different. The luminous intensity of Example 2 decreases after 1500 milliseconds of heating, while the luminous intensity of Examples 3 and 5 decreases after 1800 milliseconds. Heating is continued until the matrix emits faint light, and the entire heat-driven fluorescence emission process ends. After analysis of the experimental phenomena, it is found that the added Ba element is filled in the gaps in the unit cell. As the Ba content increases, the filling degree of the gaps inside the unit cell is different, which affects the energy transfer inside the material, resulting in differences in the duration of luminescence.

[0100] Depend on Figure 4 As can be seen from (d), the emission peak position of the heat-driven time-dependent dynamic multicolor fluorescent material prepared in Example 4 is also located near 400nm and 500nm, but its luminescence process is a dynamic multicolor luminescence process. In the first 1500 milliseconds, the sample mainly emits green light, because as the heating time increases, the increase in the green light emission peak intensity at the 500nm position is more obvious, and the increase in the blue-violet light emission peak intensity at the 400nm position is smaller; between 1500 milliseconds and 1800 milliseconds, the sample luminescence color gradually changes to cyan, because the green luminescence peak intensity is still significantly stronger than the blue-violet light emission; from 1500 milliseconds onwards, the green light intensity gradually weakens, while the blue-violet light intensity continues to increase. , until 2100 milliseconds when the blue-violet light emission intensity reaches the highest point, while the green light emission intensity is slightly weaker than the blue-violet light emission intensity, at which time the sample emits obvious blue-violet light; as the heating time increases, the sample basically only emits a single blue-violet light, and like other embodiments, as the heating time increases, the single blue-violet light intensity gradually weakens; but there are also features different from other embodiments, for example, as the heating time increases, only the luminous intensity of other embodiments changes without involving a change in luminous color, but the luminous intensity and luminous color of Embodiment 4 will change significantly with the heating time, and this embodiment exhibits obvious dynamic multicolor fluorescence emission under thermal drive.

[0101] like Figure 4 As shown in (f), the emission peak position of the heat-driven time-dependent dynamic multicolor fluorescent material prepared in Comparative Example 1 is the same as that of the other embodiments, both located near 400nm and 500nm, but both the green light emission and the blue-violet light emission intensities are relatively weak, basically the same as the matrix luminescence intensity. Although consistent with the other embodiments, the luminescence intensity first increases and then weakens with the extension of the heating time, but due to the overall weak luminescence intensity, not much analysis is given.

[0102] (5) Thermally driven dynamic multicolor fluorescence emission colors:

[0103] The dynamic multicolor fluorescence emission color of the heat-driven time-dependent dynamic multicolor fluorescent material (disk-shaped) prepared in Example 4 was identified, and the luminescence spectrum was imported into the software to obtain a chromaticity diagram, and the chromaticity diagram was extracted and analyzed. Figure 5 This is a chromaticity diagram of the dynamic multicolor fluorescence emission colors of the heat-driven time-dependent dynamic multicolor fluorescent material prepared in Example 4, wherein x represents the relative value related to red, and y represents the relative value related to green.

[0104] like Figure 5 As shown, with the extension of the heating time at 250 °C, the luminescent color of the sample gradually changes from green to blue-purple, which corresponds well to the dynamic multicolor fluorescence emission spectrum.

[0105] To sum up, the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code provided by the present invention integrates information and anti-counterfeiting compared with the current common anti-counterfeiting technology. The information-bearing carrier carries different information, which is read by direct heating. The information carried by the carrier with dynamic multi-color fluorescent emission characteristics is real information, and the information carried by other carriers that do not have this feature is interference, thereby achieving a high level of information anti-counterfeiting and opening up new ideas for information anti-counterfeiting technology.

[0106] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention rather than all the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A thermally driven time-dependent dynamic multicolor fluorescent material, characterized in that: Its chemical composition is: Ba 1- x K 0.05 Eu 0.02 MgSiO4, 0<x≤0.

1.

2. The thermally driven time-dependent dynamic multicolor fluorescent material according to claim 1, characterized in that: 0＜x≤0.07。 3. The method for preparing the heat-driven time-dependent dynamic multicolor fluorescent material according to claim 1 or 2, characterized in that: The following steps are involved: According to the stoichiometric ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, BaCO3, K2CO3, Eu2O3, MgO and SiO2 are mixed and wet-milled, and the obtained ball-milled slurry is dried and then first sintered in air to obtain a first sintered material; The first sintered material is crushed and then pressed, and the obtained pressed body is subjected to a second sintering in a reducing atmosphere to obtain the thermally driven time-dependent dynamic multi-color fluorescent material.

4. The preparation method according to claim 3, characterized in that: The temperature of the first sintering is 900-1100° C.; the time of the first sintering is 2-6 hours; the reducing atmosphere is hydrogen or carbon monoxide; the temperature of the second sintering is 1100-1300° C.; the time of the second sintering is 2-6 hours.

5. A thermally driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material, characterized in that: The preparation raw materials include heat-driven time-dependent dynamic multicolor fluorescent material, polydimethylsiloxane, polydimethylsiloxane curing agent and softener; The thermally driven time-dependent dynamic multi-color fluorescent material is the thermally driven time-dependent dynamic multi-color fluorescent material according to claim 1 or 2 or the thermally driven time-dependent dynamic multi-color fluorescent material prepared by the preparation method according to claim 3 or 4.

6. The heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material according to claim 5, characterized in that: The polydimethylsiloxane and the polydimethylsiloxane curing agent are two-component Dow Corning DC184 silicone rubber; the softener is a silicone oil substance.

7. The heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material according to claim 5 or 6, characterized in that: The mass ratio of the heat-driven time-dependent dynamic multicolor fluorescent material, polydimethylsiloxane, polydimethylsiloxane curing agent and softener is 20-40:10-20:1-2:1-2.

8. The method for preparing the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material according to any one of claims 5 to 7, characterized in that: The method comprises the following steps: mixing the heat-driven time-dependent dynamic multi-color fluorescent material, polydimethylsiloxane, a polydimethylsiloxane curing agent and a softener, placing the obtained mixed mucus in a mold, and demolding after drying to obtain the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material.

9. Use of the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material according to any one of claims 5 to 7 or the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material prepared by the preparation method according to claim 8 in information anti-counterfeiting.

10. A heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code, characterized in that: Including a thermally driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material after charging; The heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material is the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material according to any one of claims 5 to 7 or the heat-driven time-dependent dynamic multi-color fluorescent anti-counterfeiting four-dimensional code material prepared by the preparation method according to claim 8.

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