Choline manganese chloride temperature-responsive fluorescent anti-counterfeiting mark and verification method thereof
Patent Information
- Application Number
- CN202611120124.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-27
- Publication Date
- 2026-10-23
AI Technical Summary
但是，不同发光材料的激发条件、发射颜色、热稳定性和加工性能可能存在差异，材料之间还可能发生能量传递、光谱重叠或相互干扰，使防伪标识的材料选择、配比控制和加工过程较为复杂
（1）本发明提供了一种具有温度阈值响应特性的Mn(II)基有机-无机杂化红光粉体材料，该材料区别于常规连续热猝灭型发光材料，在特定温度区间内表现出显著的发光强度增强行为，具有明确的温度触发特征。
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Figure CN122967532A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of luminescent materials and optical anti-counterfeiting technology, specifically relating to a choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label and its verification method. Background Technology
[0002] Organic-inorganic hybrid metal halide materials combine the advantages of tunable organic component structure and ease of functionalization with the excellent optical activity of inorganic metal halides, showing promising application potential in fields such as light-emitting displays, optical sensing, information encryption, and fluorescent anti-counterfeiting. Among them, Mn(II)-based organic-inorganic hybrid halides have attracted widespread attention in recent years due to their abundant raw material sources, relatively low preparation costs, long luminescence lifetimes, and tunable local coordination environments. 2+ The electronic transition behavior of ions is highly sensitive to their surrounding coordination structure and crystal field environment. When materials are subjected to external conditions such as temperature, their local structure, crystal field strength, and electron-phonon coupling may change, leading to variations in optical parameters such as luminescence intensity, emission peak position, luminescence lifetime, or luminescence color. Therefore, Mn(II)-based organic-inorganic hybrid halides have the potential to be used to construct externally responsive luminescent materials.
[0003] Existing research has already involved chemical formulas [C5H 14 [NO]MnCl3 is a choline manganese chloride organic-inorganic hybrid material, and research mainly focuses on its crystal structure, basic photoluminescence properties, and room-temperature luminescence characteristics. This type of material can produce red emission under ultraviolet or near-ultraviolet light excitation. However, current techniques typically treat it as a general photoluminescent material, paying less attention to the differentiated luminescence behavior exhibited by this material in different temperature ranges during heating. In particular, phenomena such as discontinuous luminescence response, abrupt changes in luminescence intensity, and changes in emission peak position that may occur within specific temperature ranges are lacking for further functionalization development. At the same time, existing studies mostly use crystalline samples for structural and luminescence property characterization, with relatively insufficient research on powder materials suitable for polymer composites, film formation, and patterning processes, and their applications.
[0004] Fluorescent anti-counterfeiting technology primarily utilizes the color, brightness, or spectral signals generated by luminescent materials under specific excitation conditions to achieve information concealment and authenticity verification. Compared to ordinary printed anti-counterfeiting measures, fluorescent anti-counterfeiting offers advantages such as better concealment, faster identification speed, and the ability to perform non-contact detection. Existing fluorescent anti-counterfeiting labels typically use a single fluorescent material to construct patterns, characters, barcodes, or QR codes, revealing the hidden information under ultraviolet light. However, relying solely on whether the material emits light or a single luminescent color for identification results in relatively limited verification information, making it easy to counterfeit with materials possessing similar luminescent colors, and thus failing to meet the requirements for higher security levels of anti-counterfeiting.
[0005] To enhance information capacity and reduce the difficulty of counterfeiting, existing technologies have proposed temperature-responsive fluorescent anti-counterfeiting schemes. These schemes involve changing the color or brightness of luminescent materials through heating or cooling, thereby achieving dynamic information display. However, most temperature-responsive luminescent materials exhibit continuous thermal quenching during heating, meaning that the luminous intensity gradually decreases as the temperature rises. This pattern is relatively common and provides limited feature information. Furthermore, when using luminous intensity as the sole judgment parameter, the detection results are easily affected by factors such as excitation power, illumination distance, material dosage, pattern thickness, shooting angle, and ambient light, potentially leading to reduced accuracy and repeatability in identification.
[0006] Some existing multi-level or multi-channel fluorescent anti-counterfeiting systems combine multiple luminescent materials, allowing each material to respond to external stimuli such as temperature, humidity, light, or chemical substances to obtain multiple identification signals. However, the excitation conditions, emission colors, thermal stability, and processing properties of different luminescent materials may vary. Energy transfer, spectral overlap, or mutual interference may also occur between materials, making the selection, proportioning, and processing of anti-counterfeiting labels quite complex. Furthermore, the multiple optical signals generated by different materials are usually independent of each other, lacking intrinsic correlation, which still poses a risk of replicating anti-counterfeiting information by separately imitating each luminescent area. Summary of the Invention
[0007] To address the above problems, this invention provides a choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label, comprising a substrate and a first luminescent coding unit disposed on the substrate. The first luminescent coding unit comprises a choline manganese chloride red light powder material and a polymer matrix. The choline manganese chloride red light powder material is dispersed in the polymer matrix, and the chemical formula of the choline manganese chloride red light powder material is [C5H]. 14 NO]MnCl3; The first luminescent coding unit is arranged according to a preset image, character and / or dot matrix; Under light excitation, the first luminescent coding unit emits red light and generates a temperature threshold response with enhanced luminescence intensity and shift of the emission peak to the long wavelength direction when the temperature rises to a preset temperature threshold range, so that the fluorescent anti-counterfeiting label forms anti-counterfeiting verification information based on at least two parameters among pattern state, luminescence intensity and emission peak position.
[0008] This invention utilizes the differentiated optical response of choline manganese chloride red light powder material within different temperature ranges to achieve multidimensional fluorescent anti-counterfeiting through a single material: at room temperature and below a preset temperature threshold, the choline manganese chloride red light powder material stably emits red light under photoexcitation conditions, enabling the first light-emitting coding unit, arranged according to a preset image, character, and / or dot matrix, to form basic pattern information; when the temperature rises to the preset temperature threshold range, the temperature induces the local structure of the material and Mn...2+ The adjustment of the crystal field environment surrounding the ions significantly enhances the luminescence intensity of the first luminescent coding unit, while the emission peak shifts towards longer wavelengths. This generates interconnected luminescence intensity and emission peak position signals based on the original pattern information. Since the pattern state, luminescence intensity changes, and emission peak shifts all originate from the temperature response process of the same choline manganese chloride material, there is an inherent correspondence between the verification parameters. This enables the formation of a multi-layered anti-counterfeiting mechanism encompassing pattern recognition, threshold triggering, and spectral verification. It eliminates the need for multiple independent stimulus-response materials, thus reducing issues such as spectral overlap, energy transfer, and response inconsistencies between different materials. This simplifies the preparation and detection process of anti-counterfeiting labels while improving information capacity, recognition efficiency, verification reliability, and counterfeiting difficulty.
[0009] Furthermore, under light excitation conditions of 350-420 nm, the choline manganese chloride red light powder material produces red emission; its integrated luminescence intensity remains relatively stable in the range of 25-125 °C; when the temperature increases from 125 °C to 150 °C, the ratio of its integrated luminescence intensity at 150 °C to that at 125 °C is not less than 8, and its emission peak shifts 15-25 nm towards the longer wavelength direction.
[0010] Furthermore, the polymer matrix is polydimethylsiloxane, and the choline manganese chloride red light-emitting powder material is uniformly dispersed in the polydimethylsiloxane. After degassing, molding, and curing, a flexible light-emitting film is formed. This flexible light-emitting film is then processed to form the first light-emitting coding unit. Polydimethylsiloxane possesses excellent light transmittance, flexibility, heat resistance, and molding and processing performance. It can fix and protect the powder particles without significantly affecting the photoexcitation and temperature threshold response characteristics of the choline manganese chloride red light-emitting powder material. The uniform dispersion of the powder material in polydimethylsiloxane helps improve the uniformity of light emission and temperature response consistency in different areas of the light-emitting film. The degassing treatment reduces light scattering, localized uneven light emission, and structural defects caused by internal air bubbles. The flexible light-emitting film obtained after molding and curing can be bent, cut, and processed into patterns, characters, or dot matrix coding units of different shapes and sizes, facilitating attachment to curved or irregular substrate surfaces. This improves the structural stability, processing flexibility, environmental adaptability, and identification reliability of the fluorescent anti-counterfeiting label.
[0011] Furthermore, it also includes a second light-emitting coding unit disposed on the substrate, the second light-emitting coding unit comprising a thermally quenched light-emitting reference material; at a first temperature state, the first light-emitting coding unit and the second light-emitting coding unit have similar light-emitting appearances, so that the preset anti-counterfeiting information formed by the two together is hidden; at a second temperature state higher than the first temperature state, the light intensity of the second light-emitting coding unit decreases due to thermal quenching, while the first light-emitting coding unit continues to emit light, so that the preset anti-counterfeiting information is displayed; at a third temperature state higher than the second temperature state, the first light-emitting coding unit generates a temperature threshold response with enhanced light intensity and a shift of the emission peak towards the long-wavelength direction, so as to form further anti-counterfeiting verification information. This invention constructs a multi-stage anti-counterfeiting process by setting up a first and a second luminescent coding unit with different temperature response characteristics. This process involves concealment at room temperature, manifestation upon temperature rise, and verification via high-temperature spectroscopy. At the first temperature, the two coding units have similar luminescent appearances, making it difficult to directly identify genuine anti-counterfeiting information. At the second temperature, the thermal quenching characteristics of the second luminescent coding unit contrast sharply with the relatively stable luminescence characteristics of the first unit, causing the hidden information to automatically appear. At the third temperature, the enhanced luminescence intensity and redshift of the emission peak of the first luminescent coding unit are used for secondary verification. This scheme links pattern changes, intensity changes, and peak position changes in a temperature-dependent order, increasing the layers and dimensions of anti-counterfeiting information and reducing the possibility of counterfeiting based solely on a single color or brightness. This improves the concealment, reliability, and difficulty of counterfeiting of anti-counterfeiting labels.
[0012] Furthermore, the thermally quenched luminescent reference material is CsMnCl3; the first luminescent coding unit and the second luminescent coding unit are respectively in the form of dots, lines, blocks, characters and / or diagrams, and are disposed on the substrate in an alternating, spaced, arrayed or inlaid manner.
[0013] Furthermore, the choline manganese chloride red light powder material is prepared through the following steps: MnCl2·4H2O and choline chloride were added to alcohol at a molar ratio of 1:1 and stirred at room temperature to obtain a suspension containing manganese chloride containing choline. Solid-liquid separation is performed on the suspension, and the precipitate is collected; The precipitate was washed sequentially with acetic acid and ethanol; The washed precipitate was dried to obtain the chemical formula [C5H]. 14 NO]MnCl3 choline manganese chloride red light powder material.
[0014] Furthermore, the flexible light-emitting film is prepared through the following steps: The choline manganese chloride red light powder material was sieved through a 200-mesh sieve and then added to the polydimethylsiloxane prepolymer and mixed evenly. Add a curing agent to the mixture, mix, and then degas. The degassed mixture is placed into a mold and cured at 70°C to obtain a flexible light-emitting film.
[0015] Furthermore, the first light-emitting coding unit and / or the second light-emitting coding unit constitute text, numbers, symbols, graphics, barcodes, QR codes, or dot matrix information composed of multiple discrete coding points; wherein, the first light-emitting coding unit constitutes valid identification information, and the second light-emitting coding unit constitutes background information or interference information used to hide the valid identification information.
[0016] On the other hand, the present invention provides a method for verifying choline manganese chloride temperature-responsive fluorescent anti-counterfeiting labels, comprising the following steps: Under preset photoexcitation conditions, collect the luminescence image and / or emission spectrum of the fluorescent anti-counterfeiting label at the initial temperature state; The fluorescent anti-counterfeiting label is heated, and the luminescent image of the fluorescent anti-counterfeiting label is collected at the preset pattern display temperature. The first-level verification is performed based on whether the preset anti-counterfeiting information is displayed. Continue to heat the fluorescent anti-counterfeiting label, and collect the emission spectrum of the first luminescent coding unit within the temperature threshold response range of the choline manganese chloride red light powder material; Secondary verification is performed based on the changes in integral luminescence intensity and emission peak position of the first luminescent coding unit before and after the temperature threshold response; The authenticity of the fluorescent anti-counterfeiting label is determined based on the results of the first-level verification and the second-level verification.
[0017] Furthermore, the integrated luminescence intensity and emission peak position of the first luminescent coding unit at 125℃ are used as the baseline parameters before the temperature threshold response, and the integrated luminescence intensity and emission peak position of the first luminescent coding unit at 150℃ are used as the verification parameters. When the ratio of the integrated luminescence intensity at 150℃ to that at 125℃ is not less than 8, and the emission peak at 150℃ shifts 15-25nm in the long-wavelength direction relative to the emission peak at 125℃, the secondary verification is deemed to have passed. When the preset anti-counterfeiting information is displayed in the preset temperature change order and the secondary verification is passed, the fluorescent anti-counterfeiting label is deemed to meet the preset anti-counterfeiting verification conditions.
[0018] The beneficial effects of this invention are: (1) The present invention provides a Mn(II)-based organic-inorganic hybrid red light powder material with temperature threshold response characteristics. This material is different from conventional continuous thermal quenching light-emitting materials. It exhibits significant light intensity enhancement behavior within a specific temperature range and has clear temperature triggering characteristics.
[0019] (2) The red light powder material can simultaneously produce changes in luminescence intensity and emission peak position during temperature stimulation. The two optical parameters originate from the same material response process, which can form a correlated dual-parameter identification signal and improve the reliability of anti-counterfeiting information.
[0020] (3) The red light powder material can be prepared by room temperature liquid phase method and can be combined with polymer matrix to form flexible light-emitting film. It has the characteristics of mild preparation conditions, flexible processing method and easy patterning and coding.
[0021] (4) By combining the red light powder material with the thermal quenching luminescent reference material, a multi-stage optical anti-counterfeiting system with room temperature information hiding, heating pattern display and high temperature dual parameter verification is constructed, which improves the information encoding dimension and the difficulty of counterfeiting.
[0022] Based on the above beneficial effects, this invention has good application prospects in the fields of luminescent materials and optical anti-counterfeiting technology. Attached Figure Description
[0023] Figure 1 Figures showing the structural composition, phase composition, and morphology of the choline manganese chloride red light powder material of the present invention: (a) structural composition, (b) X-ray diffraction pattern, and (c) scanning electron microscope image. Figure 2 The figure shows the test results of the room temperature photoluminescence performance of the choline manganese chloride red light powder material of the present invention; Figure 3 The temperature-dependent luminescence response results of the choline manganese chloride red light powder material of the present invention are shown in the figures: (a) luminescence spectrum at different temperatures, and (b) integrated luminescence intensity at different temperatures. Figure 4 This is a graph showing the refined temperature-dependent luminescence test results of the choline manganese chloride red light powder material of the present invention within the temperature threshold response range; Figure 5 Figures showing the structural changes and thermal analysis results of the choline manganese chloride red light powder material during the temperature response process of the present invention: (a) X-ray diffraction patterns after different temperature treatments, (b) thermogravimetric analysis diagram; Figure 6 The temperature response performance and color coordinate change results of the flexible luminescent film after the choline manganese chloride red light powder material of the present invention are shown in the following figures: (a) CIE colorimetric diagram, (b) CIE color coordinate diagram at different temperatures, and (c) color difference curve with temperature. Figure 7 This is a schematic diagram of a multi-stage fluorescent anti-counterfeiting label constructed based on the choline manganese chloride red light powder material of the present invention and its verification process. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments.
[0025] Example 1
[0026] This embodiment uses a room-temperature liquid-phase method to prepare choline manganese chloride red-light powder material. Details are as follows: Weigh 0.1979 g of MnCl2·4H2O and 0.1396 g of choline chloride, with a molar ratio of 1:1. Add both to 5 mL of ethanol and stir at room temperature for 2 h. During the reaction, a suspension gradually forms.
[0027] The resulting suspension was separated into solid and liquid components by centrifugation. The precipitate was collected and washed sequentially with acetic acid and ethanol to remove any remaining unreacted raw materials and solvents. The washed precipitate was dried at 70°C for 8 hours and then cooled to obtain choline manganese chloride red light powder material with the chemical formula [C5H]. 14 NO]MnCl3.
[0028] Figure 1 The figures show the structural composition, phase composition, and morphological characterization results of the obtained sample. The test results indicate that the diffraction peaks of the obtained powder match the target phase, and no obvious impurity phase peaks were observed, demonstrating that the room temperature liquid phase method can obtain the pure phase [C5H]. 14 [NO]MnCl3 powder material. Scanning electron microscopy (SEM) observation showed that the obtained powder mainly exhibited an irregular particle morphology at the micrometer scale. Elemental surface scanning results indicated that C, N, O, Mn, and Cl elements were uniformly distributed within the sample area. Furthermore, the Au signal detected by energy-dispersive X-ray spectroscopy originated from the gold sputtering process during the SEM testing.
[0029] Example 2
[0030] This embodiment tests the room-temperature photoluminescence properties of the choline manganese chloride red light powder material prepared in Example 1. Details are as follows: The excitation spectrum of the powder obtained in Example 1 was tested at a monitoring wavelength of 640 nm, and its excitation band covered the range of 300-600 nm. Figure 2 As shown, under 370 nm light excitation, the powder material exhibits broadband red emission at approximately 640 nm, which is attributed to Mn. 2+ Ion-related 4 T1→ 6 A1 transition. Its luminescence lifetime was measured to be approximately 1.11 ms at room temperature. These results indicate that [C5H] prepared by the room temperature liquid-phase method... 14NO]MnCl3 powder has stable red light emission characteristics and can be used as a temperature-responsive optical functional material.
[0031] Example 3
[0032] In this embodiment, under the same excitation light source, detection distance, and spectral acquisition conditions, the red light powder material prepared in Example 1 was subjected to temperature-varying emission spectroscopy testing within the range of 25-250℃. Details are as follows: Figure 3 This diagram shows the temperature-dependent luminescence response of the choline manganese chloride red light powder material of this invention. The test results indicate that as the temperature gradually increases from 25°C to 125°C, the integrated luminescence intensity of the red light powder material remains relatively stable, without significant continuous thermal quenching. When the temperature further increases from 125°C to 150°C, the integrated luminescence intensity significantly increases, with the intensity at 150°C being more than eight times higher than that at 125°C. Simultaneously, the emission peak shifts approximately 20 nm towards longer wavelengths.
[0033] As the temperature continues to rise, the luminescence intensity of the red light powder material further increases, reaching a maximum at approximately 160°C; when the temperature continues to rise to 250°C, its luminescence intensity gradually decreases to a level close to room temperature.
[0034] Furthermore, within the temperature range of 125-175℃, the red light-emitting powder material underwent refined temperature-varying luminescence testing at 5℃ intervals. For example... Figure 4 As shown, the abrupt change in luminescence intensity of the red-light powder material mainly occurs in the temperature range of 145-150℃; when the temperature exceeds 150℃, the luminescence intensity continues to increase, reaching a maximum value near approximately 160℃. Normalized emission spectra show a shift of approximately 20 nm in the emission peak before and after the temperature threshold response.
[0035] The above test results indicate that [C5H 14 Unlike typical luminescent materials that undergo continuous thermal quenching with increasing temperature, MnCl3 red-light powder material exhibits a distinct temperature threshold response within a specific temperature range. Its enhanced luminescence intensity and the shift of the emission peak towards longer wavelengths together constitute an interrelated optical verification signal.
[0036] Example 4
[0037] This embodiment analyzes the structural changes during the temperature threshold response process. Specifically: To analyze the source of the temperature threshold response behavior of the choline manganese chloride red light powder material, the red light powder material prepared in Example 1 was treated at 100℃, 150℃ and 200℃ respectively, and the treated samples were subjected to powder X-ray diffraction tests.
[0038] Figure 5 (a) is a diagram showing the structural changes of the choline manganese chloride red light powder material during the temperature response process of the present invention. The test results show that the sample treated at 100℃ still retains the original main diffraction characteristics; when the temperature is raised to 150℃, some diffraction peaks of the sample change, indicating that the material has undergone structural adjustment in this temperature range; after the temperature is further raised to 200℃, the sample still maintains obvious crystalline diffraction characteristics.
[0039] Further thermogravimetric analysis was performed on the aforementioned red light powder material. Figure 5 (b) is the thermogravimetric analysis diagram. The test results show that the sample did not show significant mass loss below 250℃, indicating that the sudden change in luminescence intensity around 145-150℃ was not mainly caused by material decomposition or volatilization. Differential scanning calorimetry results show that the sample exhibits a thermal effect peak during heating and a corresponding thermal effect during cooling, indicating that the material undergoes thermally induced structural changes during heating and cooling.
[0040] Combining the results of variable-temperature X-ray diffraction, thermal analysis, and variable-temperature luminescence testing, it can be seen that the choline manganese chloride red light powder material undergoes structural adjustment within a preset temperature threshold range, and the structural adjustment alters the Mn content. 2+ The local structure and crystal field environment surrounding the ions, in turn, produce an optical response that enhances luminescence intensity and shifts the emission peak toward longer wavelengths.
[0041] Example 5
[0042] This embodiment prepares a flexible luminescent film containing choline manganese chloride. Details are as follows: Weigh 0.3 g of the choline manganese chloride red light powder material prepared in Example 1, and after passing it through a 200-mesh sieve, add it to 15 mL of polydimethylsiloxane (PDMS) prepolymer. Stir thoroughly to ensure that the red light powder material is uniformly dispersed in the PDMS prepolymer.
[0043] Subsequently, 3 mL of curing agent was added to the mixture, and stirring was continued until the mixture was homogeneous. The mixture was then allowed to stand for 1 hour to degas, thereby reducing air bubbles inside the mixture. The degassed mixture was then poured into a mold of a pre-shaped shape and cured at 70°C for 10 hours. After cooling, the mixture was demolded to obtain a choline manganese chloride flexible luminescent film.
[0044] Temperature-dependent luminescence tests were conducted on the obtained flexible luminescent film. The test results showed that when the temperature increased from 125℃ to 150℃, the flexible luminescent film still exhibited a significant increase in luminescence intensity and a change in emission color, indicating that dispersing the choline manganese chloride red light powder material in polydimethylsiloxane and then curing it into a film did not significantly damage its temperature threshold response characteristics.
[0045] Polydimethylsiloxane can fix and protect red light powder materials. The resulting flexible light-emitting film has a certain degree of flexibility and can be cut, punched or molded according to the anti-counterfeiting code requirements. It can also be attached to the surface of flat, curved or irregularly shaped substrates.
[0046] Example 6
[0047] This embodiment constructs a first luminescent coding unit and a fluorescent anti-counterfeiting label. Details are as follows: According to the preset anti-counterfeiting information, the flexible luminescent film prepared in Example 5 is processed into a first luminescent coding unit in the form of dots, lines, blocks, characters or pictures, and multiple first luminescent coding units are arranged on the surface of the substrate according to preset images, characters and / or dot matrix to form a choline manganese chloride temperature threshold responsive fluorescent anti-counterfeiting mark.
[0048] The preset anti-counterfeiting information can be text, numbers, symbols, graphics, barcodes, QR codes, or dot matrix information formed by multiple discrete coded points. Under light excitation, the first light-emitting coding unit emits red light, enabling the preset pattern or coded information to be identified.
[0049] When the temperature is below a preset temperature threshold range, the first light-emitting encoding unit maintains relatively stable red light emission; when the temperature rises to the preset temperature threshold range, the luminescence intensity of the first light-emitting encoding unit significantly increases, and the emission peak shifts towards longer wavelengths. Thus, the same first light-emitting encoding unit can simultaneously provide verification information such as pattern state, luminescence intensity, and emission peak position.
[0050] In practical applications, the pattern, character or dot matrix formed by the first luminescent coding unit can be identified first by luminescent image recognition, and then the fluorescent anti-counterfeiting mark can be further verified by heating it and detecting changes in luminescence intensity and emission peak position.
[0051] Example 7
[0052] To enhance the anti-counterfeiting information, this embodiment constructs a multi-stage temperature-responsive fluorescent anti-counterfeiting label. Details are as follows: A second light-emitting coding unit is further disposed on the substrate. The second light-emitting coding unit contains a thermally quenched light-emitting reference material.
[0053] In this embodiment, CsMnCl3 is used as a thermally quenched luminescent reference material to prepare [C5H 14 NO]MnCl3 / PDMS composite film and CsMnCl3 / PDMS composite film, and process the two composite films into first light-emitting coding units and second light-emitting coding units of the same or similar size. The first light-emitting coding units and second light-emitting coding units are arranged on the surface of the substrate according to a preset pattern or dot matrix.
[0054] Under the first temperature condition, the first light-emitting coding unit and the second light-emitting coding unit have similar light-emitting appearances, so that the preset anti-counterfeiting information formed by the two together is hidden and it is not easy to identify the real coding information by direct observation.
[0055] After the anti-counterfeiting label is heated to a second temperature state higher than the first temperature state, the luminous intensity of the thermal quenching luminous reference material in the second luminous coding unit decreases, while the first luminous coding unit continues to emit light, thereby creating a clear luminous difference between the first and second luminous coding units, which makes the hidden patterns, characters or dot matrix information appear.
[0056] The anti-counterfeiting label is heated to the third temperature state. When the temperature reaches the temperature threshold response range of the choline manganese chloride red light powder material, the luminescence intensity of the first luminescent coding unit is further enhanced, and the emission peak moves towards the long wavelength direction. Thus, on the basis of pattern display, luminescence intensity and emission peak position verification information are further formed, realizing a multi-stage anti-counterfeiting process of room temperature information hiding, heated pattern display, and high temperature spectrum verification.
[0057] Example 8
[0058] This embodiment provides a method for verifying fluorescent anti-counterfeiting labels. Details are as follows: The fluorescent anti-counterfeiting labels prepared in Example 6 or Example 7 were placed in a temperature control device and verified under fixed excitation light source, irradiation distance, detection angle and collection conditions.
[0059] First, under initial temperature conditions, fluorescent anti-counterfeiting labels are irradiated with excitation light in the range of 350-420nm, their luminescence images and / or emission spectra are collected, and the initial pattern state, integrated luminescence intensity and emission peak position are recorded.
[0060] Subsequently, the fluorescent anti-counterfeiting label is heated. In the case of a second luminescent coding unit, when the temperature rises to the preset pattern display temperature, the second luminescent coding unit undergoes thermal quenching, while the first luminescent coding unit continues to emit light, thus displaying the preset anti-counterfeiting information. First-level verification is then performed based on the shape, arrangement, and display state of the preset anti-counterfeiting information.
[0061] The fluorescent anti-counterfeiting label was further heated, and the emission spectrum of the first luminescent coding unit was collected within the temperature threshold response range of the choline manganese chloride red light powder material. Secondary verification was performed based on the changes in the integrated luminescence intensity and emission peak position of the first luminescent coding unit before and after the temperature threshold response.
[0062] In one specific verification method, the integrated luminescence intensity and emission peak position of the first luminescent coding unit at 125℃ are used as the baseline parameters before the temperature threshold response, and the integrated luminescence intensity and emission peak position at 150℃ are used as the verification parameters. When the integrated luminescence intensity at 150℃ is more than 8 times higher than that at 125℃, and the emission peak shifts approximately 20nm towards the longer wavelength direction, the first luminescent coding unit is determined to meet the preset temperature threshold response condition.
[0063] When the preset anti-counterfeiting information is displayed according to the preset temperature change process, and the changes in the integrated luminescence intensity and the position of the emission peak of the first luminescent coding unit both meet the preset conditions, the fluorescent anti-counterfeiting mark is determined to have passed verification.
[0064] Figure 6 This image shows the temperature response performance and color coordinate changes of the flexible luminescent film after the choline manganese chloride red light powder material of this invention is composited. From... Figure 6 As can be seen, the emission color of the flexible light-emitting film gradually changes with increasing temperature. Its CIE color coordinates shift from (0.613, 0.386) at 125℃ to (0.657, 0.342) at 150℃, and the corresponding color difference value changes significantly. This indicates that the choline manganese chloride red light powder, after being composited with the polymer matrix, still maintains obvious temperature-responsive luminescence characteristics and can be used to construct temperature-triggered luminescence coding units.
[0065] Figure 7 This is a schematic diagram illustrating the multi-stage fluorescent anti-counterfeiting label constructed based on the choline manganese chloride red light powder material of this invention and its verification process. Figure 7 As can be seen from [C5H] 14 The MnCl3 / PDMS composite film exhibits a significant color change during the temperature threshold response process. By collecting and analyzing the emission color of the composite film at different temperatures using a mobile phone color recognition program, it was found that when the temperature increased from 125℃ to 150℃, its CIE chromaticity coordinates changed from (0.613, 0.386) to (0.657, 0.342), indicating that the material has a recognizable color change during temperature triggering, which can be used as a temperature-responsive optical verification signal.
[0066] Further use of [C5H 14NO]MnCl3 / PDMS composite film and CsMnCl3 / PDMS composite film were used to construct the first and second luminescent coding units, respectively, and arranged according to a preset pattern to form a nine-square grid anti-counterfeiting mark. At the initial temperature, the first and second luminescent coding units exhibit similar luminescent appearances, keeping the preset anti-counterfeiting information hidden. As the temperature rises to 125℃, the CsMnCl3 / PDMS composite film in the second luminescent coding unit undergoes fluorescent thermal quenching, while the first luminescent coding unit continues to emit light, revealing the hidden pattern information and achieving primary pattern verification. Further increasing the temperature to 150℃, the luminescence intensity of the first luminescent coding unit increases, accompanied by a shift of the emission peak towards longer wavelengths, thus forming a secondary optical verification signal based on the integral luminescence intensity and the change in the emission peak position. The above results indicate that based on [C5H 14 The anti-counterfeiting system constructed from NO]MnCl3 / PDMS composite film can realize a multi-stage identification process of information hiding, pattern display, and temperature threshold dual-parameter verification.
[0067] In summary, this invention utilizes the characteristic of choline manganese chloride material exhibiting a sudden increase in luminescence intensity accompanied by a redshift of the emission peak within a specific temperature range to construct a temperature threshold-responsive fluorescent anti-counterfeiting label integrating pattern recognition, intensity verification, and spectral verification. This scheme can achieve multi-parameter correlation verification using a single material and can be composited with flexible polymers to form easily cut, attached, and patterned coding units. It boasts advantages such as simple preparation, rich information dimensions, reliable recognition, and high counterfeiting difficulty, making it suitable for anti-counterfeiting identification and information encryption of product packaging, tickets, electronic devices, important documents, and temperature-sensitive products.
[0068] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. A choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label, comprising a substrate and a first luminescent coding unit disposed on the substrate, characterized in that: The first luminescent encoding unit comprises a choline manganese chloride red light-emitting powder material and a polymer matrix, wherein the choline manganese chloride red light-emitting powder material is dispersed in the polymer matrix, and the chemical formula of the choline manganese chloride red light-emitting powder material is [C5H]. 14 NO]MnCl3; The first luminescent coding unit is arranged according to a preset image, character and / or dot matrix; Under photoexcitation conditions, the first luminescent coding unit emits red light, and when the temperature rises to a preset temperature threshold range, it generates a temperature threshold response that enhances the luminescence intensity and shifts the emission peak to the long wavelength direction, so that the fluorescent anti-counterfeiting mark forms anti-counterfeiting verification information based on at least two parameters among pattern state, luminescence intensity and emission peak position.
2. The choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 1, characterized in that: Under light excitation conditions of 350-420 nm, the choline manganese chloride red light powder material emits red light; its integrated luminescence intensity remains relatively stable in the range of 25-125 °C; when the temperature increases from 125 °C to 150 °C, the ratio of its integrated luminescence intensity at 150 °C to that at 125 °C is not less than 8, and its emission peak shifts 15-25 nm towards the longer wavelength direction.
3. The choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 1, characterized in that: The polymer matrix is polydimethylsiloxane, and the choline manganese chloride red light powder material is uniformly dispersed in the polydimethylsiloxane. After degassing, molding and curing, a flexible light-emitting film is formed. The flexible light-emitting film is processed to form the first light-emitting coding unit.
4. The choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 1, characterized in that: It also includes a second light-emitting coding unit disposed on the substrate, the second light-emitting coding unit comprising a thermally quenched light-emitting reference material; at a first temperature state, the first light-emitting coding unit and the second light-emitting coding unit have similar light-emitting appearances, so that the preset anti-counterfeiting information formed by the two together is hidden; at a second temperature state higher than the first temperature state, the light intensity of the second light-emitting coding unit decreases due to thermal quenching, while the first light-emitting coding unit continues to emit light, so that the preset anti-counterfeiting information is displayed; at a third temperature state higher than the second temperature state, the first light-emitting coding unit generates a temperature threshold response with enhanced light intensity and a shift of the emission peak towards the long-wavelength direction, so as to form further anti-counterfeiting verification information.
5. The choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 4, characterized in that: The thermally quenched luminescent reference material is CsMnCl3; the first luminescent coding unit and the second luminescent coding unit are respectively in the form of dots, lines, blocks, characters and / or diagrams, and are disposed on the substrate in an alternating, spaced, arrayed or inlaid manner.
6. The choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 1, characterized in that: The choline manganese chloride red light powder material is prepared by the following steps: MnCl2·4H2O and choline chloride were added to alcohol at a molar ratio of 1:1 and stirred at room temperature to obtain a suspension containing manganese chloride containing choline. The suspension was subjected to solid-liquid separation, and the precipitate was collected; The precipitate was washed sequentially with acetic acid and ethanol; The washed precipitate was dried to obtain the chemical formula [C5H]. 14 NO]MnCl3 choline manganese chloride red light powder material.
7. The choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 3, characterized in that: The flexible light-emitting film is prepared by the following steps: The choline manganese chloride red light powder material was sieved through a 200-mesh sieve and then added to the polydimethylsiloxane prepolymer and mixed evenly. Add a curing agent to the mixture, mix, and then degas. The degassed mixture is placed into a mold and cured at 70°C to obtain the flexible luminescent film.
8. The choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 4, characterized in that: The first light-emitting coding unit and / or the second light-emitting coding unit constitute text, numbers, symbols, graphics, barcodes, QR codes, or dot matrix information composed of multiple discrete coding points; wherein, the first light-emitting coding unit constitutes valid identification information, and the second light-emitting coding unit constitutes background information or interference information for hiding the valid identification information.
9. The method for verifying the choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 4, characterized in that, Includes the following steps: Under preset photoexcitation conditions, the fluorescence image and / or emission spectrum of the fluorescent anti-counterfeiting label at the initial temperature state are collected; The fluorescent anti-counterfeiting label is heated, and its luminescent image is acquired at a preset pattern display temperature. First-level verification is performed based on whether the preset anti-counterfeiting information is displayed. Continue to heat the fluorescent anti-counterfeiting label, and collect the emission spectrum of the first luminescent coding unit within the temperature threshold response range of the choline manganese chloride red light powder material; Secondary verification is performed based on the changes in integral luminescence intensity and emission peak position of the first luminescent coding unit before and after the temperature threshold response; The authenticity of the fluorescent anti-counterfeiting label is determined based on the results of the primary and secondary verifications.
10. The method for verifying the choline manganese chloride temperature-responsive fluorescent anti-counterfeiting label as described in claim 9, characterized in that: The integrated luminescence intensity and emission peak position of the first luminescent coding unit at 125℃ are used as the reference parameters before the temperature threshold response, and the integrated luminescence intensity and emission peak position of the first luminescent coding unit at 150℃ are used as the verification parameters. When the ratio of the integrated luminescence intensity at 150℃ to that at 125℃ is not less than 8, and the emission peak at 150℃ shifts 15-25nm towards the longer wavelength direction relative to the emission peak at 125℃, the secondary verification is deemed to have passed; when the preset anti-counterfeiting information appears in the preset temperature change sequence and the secondary verification is passed, the fluorescent anti-counterfeiting label is deemed to have met the preset anti-counterfeiting verification conditions.