Preparation method and application of copper-based halide luminous ink
By developing a method for preparing copper-based halide luminescent ink, the complexity of synthesizing rare-earth complexes and quantum dot materials and the environmental pollution issues have been solved. This method enables low-cost, large-scale preparation and controllable color-changing luminescent ink, which can be applied to anti-counterfeiting labels and dynamic information storage.
Patent Information
- Application Number
- CN202511244027.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-02
- Publication Date
- 2025-11-11
AI Technical Summary
Existing rare earth complexes and quantum dot luminescent anti-counterfeiting materials are complex to synthesize, costly, and have poor environmental compatibility, which limits their large-scale application and makes it difficult to achieve ink-like properties and controllable color change.
A method for preparing copper-based halide luminescent ink was adopted. Cu6I8(bu-ted)2 and Cu4I6(pr-ted)2 powders were synthesized by solution method, mixed with PVP solution and ball-milled to form uniform ink. Color change was achieved by stimulation with dichloromethane and restored by saturated potassium iodide solution, thus constructing an information encryption and decryption mechanism.
It enables low-cost, large-scale preparation of efficient and stable luminescent inks with significant solvent-induced color-changing effects, is suitable for various printing processes, and provides a novel information encryption and decryption mechanism for application in anti-counterfeiting labels and dynamic information storage.
Smart Images
Figure CN120924089A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of luminescent materials technology, specifically relating to a method for preparing copper-based halide luminescent ink and its application. Background Technology
[0002] With the expansion of commodity circulation and the proliferation of counterfeit and substandard products, advanced anti-counterfeiting technology has become an important means of safeguarding brand value and public safety. Traditional anti-counterfeiting technologies, such as holographic labels, watermarks, and magnetic inks, suffer from problems such as ease of replication, difficulty in identification, or high costs. Luminescent anti-counterfeiting materials, due to their unique optical properties and difficulty in replication, have become a research hotspot.
[0003] Currently, mainstream luminescent anti-counterfeiting materials include rare earth complexes and quantum dots, but their complex synthesis, high cost, and poor environmental compatibility limit their large-scale application. Copper-based halide materials, due to their abundant raw materials, low cost, simple synthesis, high luminous efficiency, and environmental friendliness, show promising application prospects. However, achieving their large-scale synthesis, ink application, and controllable color change remains a technical challenge. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention proposes a method for preparing copper-based halide luminescent ink and its application, thereby providing a novel anti-counterfeiting luminescent material that is low-cost, easily amplified, environmentally friendly, and has reversible and adjustable luminescent color.
[0005] In a first aspect, the method for preparing the copper-based halide luminescent ink of the present invention includes the following steps: S1, Synthetic organic ligand (bu-ted) Br: Triethylenediamine (ted) was dissolved in an organic solvent, and bromobutane (bu-Br) was added dropwise. The mixture was stirred to produce a white precipitate, which was then centrifuged, washed, and dried to obtain (bu-ted)Br. S2. Preparation of organic ligand solution: Dissolve (bu-ted)Br in an organic solvent for later use; S3, Synthesizing Cu6I8(bu-ted)2 powder: Cuprous iodide was dissolved in a saturated potassium iodide solution, an organic ligand solution was added, and the mixture was stirred to produce a white powder. The product was obtained by centrifugation, washing, and drying. S4. Preparation of luminescent ink: Cu6I8(bu-ted)2 powder was mixed with an organic solvent / PVP solution and ball-milled to obtain a uniform white ink.
[0006] Furthermore, in S1, the molar ratio of triethylenediamine to n-bromobutane is 1:1, the organic solvent is acetone, the washing solvent is acetonitrile, and the centrifugation conditions are 8000 rpm for 5 minutes.
[0007] Furthermore, the organic solvent in S2 is methanol or ethanol.
[0008] Furthermore, the washing solvent in S3 includes, but is not limited to, a saturated KI solution, ethanol, and water, and the centrifugation conditions are 8000 rpm for 5 minutes.
[0009] Furthermore, in S4, the ratio of PVP to organic solvent is 1 g / 100 mL, and the ratio of powder product to solution is 30 g / 100 mL.
[0010] Furthermore, the ball mill rotation speed in S4 is 360 rpm.
[0011] Further, in S1, replacing n-butane bromide with n-propane bromide yields another organic ligand, n-propanetriethylenediamine bromide (pr-ted)Br.
[0012] Furthermore, in S3, the ligand is (pr-ted)Br to obtain another green light powder Cu4I6(pr-ted)2.
[0013] Furthermore, in step S4, the powder is replaced with Cu4I6(pr-ted)2 powder to obtain another luminescent ink with a similar color.
[0014] Secondly, the present invention provides the application of the copper-based halide luminescent ink prepared by the above method in anti-counterfeiting or information encryption.
[0015] Compared with the prior art, the beneficial effects of the present invention are: Compared with existing technologies, this invention successfully overcomes the shortcomings of traditional rare earth luminescent materials and quantum dot materials, such as complex synthesis, high cost, and strong environmental pollution. It achieves large-scale preparation of over 50 grams using a simple solution method with a yield as high as 99.88%, demonstrating promising industrialization prospects. The obtained Cu6I8(bu-ted)2 powder exhibits high luminous efficiency and good stability. After ball milling, it can form a uniform and stable colorless luminescent ink suitable for various printing processes. More importantly, this material possesses a significant solvent-induced color change effect; upon contact with dichloromethane, the luminescent color changes from greenish-yellow to orange-yellow, and this process can be rapidly and reversibly reversed by adding a saturated potassium iodide solution, thus constructing a novel information encryption and decryption mechanism. Based on these characteristics, this invention demonstrates high application flexibility and security in fields such as anti-counterfeiting labels, information hiding, and dynamic encryption, providing a practical solution for the development of next-generation environmentally friendly anti-counterfeiting materials. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments are briefly introduced below.
[0017] Figure 1 This is a schematic diagram of the Cu6I8(bu-ted)2 unit cell structure.
[0018] Figure 2 XRD pattern of Cu6I8(bu-ted)2 powder.
[0019] Figure 3 The photoluminescence spectrum of Cu6I8(bu-ted)2 powder.
[0020] Figure 4 The color of Cu6I8(bu-ted)2 ink under natural light and ultraviolet light.
[0021] Figure 5 The printing results of Cu6I8(bu-ted)2 ink on fluorescent-free paper.
[0022] Figure 6 This is a schematic diagram of the unit cell structure of Cu5I7(bu-ted)2·(CH2Cl2)2.
[0023] Figure 7 XRD pattern of Cu5I7(bu-ted)2·(CH2Cl2)2 powder.
[0024] Figure 8 CIE coordinate diagrams of Cu6I8(bu-ted)2 powder and Cu5I7(bu-ted)2·(CH2Cl2)2 powder.
[0025] Figure 9 The photoluminescence spectrum of Cu5I7(bu-ted)2·(CH2Cl2)2 powder.
[0026] Figure 10 This describes the interconversion process of Cu6I8(bu-ted)2 powder and Cu5I7(bu-ted)2·(CH2Cl2)2 powder in response to dichloromethane stimulation.
[0027] Figure 11 The real-time photoluminescence spectrum of Cu6I8(bu-ted)2 powder transformed into Cu5I7(bu-ted)2·(CH2Cl2)2 powder after the addition of dichloromethane.
[0028] Figure 12 The real-time photoluminescence spectrum of Cu5I7(bu-ted)2·(CH2Cl2)2 powder transformed into Cu6I8(bu-ted)2 powder after the addition of saturated potassium iodide solution.
[0029] Figure 13 This is an example of the anti-counterfeiting application of Cu6I8(bu-ted)2 ink in quartz molds.
[0030] Figure 14 An example of anti-counterfeiting application of Cu6I8(bu-ted)2 ink printed on non-fluorescent paper. Detailed Implementation
[0031] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.
[0032] The raw materials used in the following examples were all provided by the reagent companies: cuprous iodide (purity: >99.5%, Aladdin), potassium iodide (purity: 99.0%, Bidex Pharmaceutical), triethylenediamine (purity: 98%, Maclean), n-butane bromide (purity: 98%, Maclean), acetone (purity: 99.5%, Xilong), ethanol (analytical grade, Maclean), dichloromethane (analytical grade, Maclean), and polyvinylpyrrolidone (PVP, degree of polymerization: K 30, Bidex Pharmaceutical).
[0033] Powder diffraction was tested using an X-ray powder diffractometer (Bruker D8 ADVANCE); PL spectra and lifetime decay curves were measured using an Edinburgh FLS1000 fluorescence spectrometer.
[0034] Example 1: Preparation of Cu6I8(bu-ted)2 powder (1) Synthesis of n-Butyltriethylenediamine bromide organic ligand (bu-ted)Br: 1.12 g of triethylenediamine (Ted) (10 mmol) was dissolved in 15 mL of acetone. 1.37 g of bromobutane (10 mmol) was added under magnetic stirring. The mixture was stirred thoroughly for 12 hours, and a large amount of white precipitate was formed. The precipitate was collected by centrifugation, washed three times with acetone, and finally dried under vacuum to obtain 2.18 g of the product bu-ted ligand. (2) Synthesis of Cu6I8(bu-ted)2 powder: 35.15 g of cuprous iodide (185 mmol) was dissolved in 300 mL of saturated KI solution, and then 85 mmol of the ligand was dissolved in 170 mL of methanol. The solution was added directly to the reaction flask and stirred for 2 hours to obtain a powder sample. The powder sample was washed with saturated KI solution, ethanol, and water in sequence, and then collected by centrifugation. The mass of the powder product was approximately 53.43 g, with a chemical yield of up to 99.88%.
[0035] The crystal structure of the product Cu6I8(bu-ted)2 is as follows: Figure 1 Through powder X-ray diffraction (XRD) patterning ( Figure 2 The comparison confirmed that the powder product had high purity and consistent structure. Figure 3 As shown, the powder emits a greenish-yellow light when irradiated with 365 nm ultraviolet light.
[0036] Example 2: Synthesis of colorless luminescent ink.
[0037] 30 g of Cu6I8(bu-ted)2 powder was added to 100 mL of ethanol solution containing 1 g of PVP, and ball milled to obtain a uniform white suspension ink. Another ink for anti-counterfeiting applications was obtained by ball milling Cu4I6(pr-ted)2 powder mixed with PVP / ethanol solution.
[0038] like Figure 4 As shown, the ink appears white under natural light and emits a uniform greenish-yellow light under 365 nm ultraviolet light. The preparation method is convenient, and the ink is stable and does not easily delaminate. Figure 5 The results of printing different patterns with ink are shown. The colors presented under natural light are almost identical to those of paper without fluorescent agents. Under 365 nm ultraviolet light, the printed patterns are clearly displayed on the paper.
[0039] Example 3 Cu6I8(bu-ted)2 powder treated with dichloromethane (DCM) underwent a significant structural change, transforming into Cu5I7(bu-ted)2·(CH2Cl2)2 crystals, the structure of which is as follows: Figure 6 And through XRD patterns ( Figure 7 The comparison confirmed that the powder structure met expectations. Figure 8 The photoluminescence spectrum of Cu5I7(bu-ted)2·(CH2Cl2)2 powder shows a change in emission color, evolving continuously from an initial greenish-yellow (CIE: 0.29771, 0.53132) to orange-yellow (CIE: 0.53644, 0.45405). Figure 9 In the presence of ultraviolet light at 350 nm, it emits a bright orange-yellow light. Furthermore, research has found that adding a saturated potassium iodide solution can reduce the emitted color. Figure 10 This study demonstrates the redshift in the emission spectrum of Cu6I8(bu-ted)2 powder during the dichloromethane stimulus response period, lasting approximately 4 minutes. The addition of a saturated potassium iodide solution resulted in a rapid restoration of the emission color within 1 minute. The real-time photoluminescence spectra of these two shifts were recorded on [the image / database]. Figure 11 and Figure 12 middle.
[0040] Example 4: Application of Quartz Trough Anti-counterfeiting Pattern In a quartz groove engraved with the pattern "8888", Cu6I8(bu-ted)2 powder is added in the shape of "sysu", and then Cu4I6(pr-ted)2 powder is added to the remaining groove positions. Figure 13 The paper demonstrates that Cu6I8(bu-ted)2 ink and Cu4I6(pr-ted)2 ink are dripped into a fixed mold. After evaporation and drying, the shape is fixed as "8888". It appears as "8888" under both sunlight and ultraviolet light. After DCM processing, the hidden information "sysu" is revealed. After reading, it can be quickly restored by immersing in a saturated KI solution, thus achieving an effective closed loop for the identification and erasure of encrypted information.
[0041] Example 5: Application of Ink Anti-counterfeiting Patterns like Figure 14 The "SYSU" shape was created using Cu6I8(bu-ted)2 ink on writing paper without fluorescent dyes via screen printing. After adding Cu4I6(pr-ted)2 ink, an "8888" shape was formed. Under sunlight and ultraviolet light, the "8888" shape appeared white and greenish-yellow respectively. After DCM processing, a distinct orange-yellow "sysu" message was displayed. Finally, a saturated KI solution was used to mask the encrypted information, restoring the "8888" shape and preventing information leakage. These two examples provide innovative solutions for high-security anti-counterfeiting labels and dynamic information storage systems, with significant application value in areas such as confidential document protection, smart packaging, and military information encryption.
[0042] The above embodiments provide innovative solutions for high-security anti-counterfeiting labels and dynamic information storage systems, and have important application value in fields such as confidential document protection, smart packaging, and military information encryption.
[0043] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.
Claims
1. A method for preparing a copper-based halide luminescent ink, characterized in that, Includes the following steps: S1, Synthetic organic ligand (bu-ted) Br: Triethylenediamine was dissolved in an organic solvent, and bromobutane was added dropwise. The mixture was stirred to produce a white precipitate, which was then centrifuged, washed, and dried to obtain (bu-ted)Br. S2. Preparation of organic ligand solution: Dissolve (bu-ted)Br in an organic solvent for later use; S3, Synthesizing Cu6I8(bu-ted)2 powder: Cuprous iodide was dissolved in a saturated potassium iodide solution, an organic ligand solution was added, and the mixture was stirred to produce a white powder. The product was obtained by centrifugation, washing, and drying. S4. Preparation of luminescent ink: Cu6I8(bu-ted)2 powder was mixed with an organic solvent / PVP solution and ball-milled to obtain a uniform white ink.
2. The method for preparing the copper-based halide luminescent ink according to claim 1, characterized in that, In S1, the molar ratio of triethylenediamine to n-bromobutane is 1:1, the organic solvent is acetone, the washing solvent is acetonitrile, and the centrifugation conditions are 8000 rpm for 5 minutes.
3. The method for preparing the copper-based halide luminescent ink according to claim 1, characterized in that, The organic solvent in S2 is methanol or ethanol.
4. The method for preparing the copper-based halide luminescent ink according to claim 1, characterized in that, The washing solvent in S3 includes, but is not limited to, a saturated KI solution, ethanol, and water, and the centrifugation conditions are 8000 rpm for 5 minutes.
5. The method for preparing the copper-based halide luminescent ink according to claim 1, characterized in that, In S4, the ratio of PVP to organic solvent is 1 g / 100 mL, and the ratio of powder product to solution is 30 g / 100 mL.
6. The method for preparing the copper-based halide luminescent ink according to claim 5, characterized in that, The ball mill in S4 rotates at a speed of 360 rpm.
7. The method for preparing the copper-based halide luminescent ink according to claim 1, characterized in that, In S1, replacing n-butane with n-propane yields another organic ligand, n-propanetriethylenediamine bromide (pr-ted)Br.
8. The method for preparing the copper-based halide luminescent ink according to claim 7, characterized in that, The ligand in S3 is (pr-ted)Br, which yields another green powder, Cu4I6(pr-ted)2.
9. The method for preparing the copper-based halide luminescent ink according to claim 8, characterized in that, In step S4, the powder is replaced with Cu4I6(pr-ted)2 powder to obtain another luminescent ink with a similar color.
10. The application of the copper-based halide luminescent ink prepared by any one of claims 1-6 in anti-counterfeiting or information encryption.