Long-afterglow anti-counterfeiting ink composition and preparation method thereof

Abstract

The invention discloses a long-afterglow anti-counterfeiting ink composition and a preparation method thereof. The long-afterglow anti-counterfeiting ink composition is prepared from long-afterglow luminescent nano powder and thermoplastic compound resin. Wherein the mass ratio of the long-afterglow luminescent nano-powder to the thermoplastic compound resin is 1: (2-10), the exciting light of the long-afterglow luminescent nano-powder is ultraviolet light and / or visible light, the emission wavelength is 500-530nm, and the long-afterglow luminescent nano-powder has blue green, green or yellow green long afterglow; the solid content of the thermoplastic compound resin is 30-50%, and the softening point of the thermoplastic compound resin is 80-130 DEG C. The long-afterglow luminescent nano-powder is simple to manufacture and easy for anti-counterfeiting discrimination, the capacity of encrypted information is expanded, an environment-friendly and tunable multi-encryption mode is innovated, and multi-information encryption anti-counterfeiting application is realized by regulating and controlling the luminescent property of the long-afterglow luminescent nano-powder; the method has profound research significance and wide application prospects in avoiding interference of fluorescence on anti-counterfeiting application and expanding anti-counterfeiting encryption forms.

Description

Technical Field

[0001] The invention belongs to the technical field of anti-counterfeiting inks, and in particular relates to a long afterglow anti-counterfeiting ink composition and a preparation method thereof. Background Art

[0002] In today's era of globalization and digitalization, the demand for product anti-counterfeiting technology is growing. However, the existing anti-counterfeiting methods have single encryption technology, limited storage capacity, low security and are easy to crack and copy. Therefore, the development of new, efficient and difficult-to-copy anti-counterfeiting technology has become an urgent problem to be solved. As an advanced anti-counterfeiting method today, photoluminescent anti-counterfeiting ink has the advantages of high visibility, diverse effect selection, difficulty in forging and imitation, integrability and diversity, real-time verification and non-destructive detection, so it has broad application prospects in the field of anti-counterfeiting. However, most of the materials of current photoluminescent inks have problems such as being environmentally unfriendly and high cost, and most of them are fluorescent anti-counterfeiting with serious substrate interference, making it difficult to carry out high-level and multi-content encryption methods, all of which limit its further application.

[0003] As a photoluminescent material that stores the energy of excitation light, long afterglow materials can continue to emit light after the excitation light stops. Among them, carbon dot materials have superior optical properties, such as light conversion and reversible dynamic optical characteristics, and have the advantages of wide sources, low cost, and green environmental protection. First, the long afterglow phenomenon of carbon dots can be used for encryption; second, the stimulus-response properties of the material can be used to achieve anti-counterfeiting encryption functions. It expands the capacity of encrypted information, innovates environmentally friendly, and invents tunable multiple encryption methods. Through the research and development of long afterglow materials and the exploration of the relationship between the luminescence properties of materials and anti-counterfeiting applications, long afterglow carbon dot anti-counterfeiting inks that can be excited by visible light are synthesized to avoid the interference of fluorescent background on anti-counterfeiting applications. Mobile phone light sources can be used for anti-counterfeiting identification, making anti-counterfeiting identification convenient and feasible. The research and development of long afterglow materials has profound research significance and broad application prospects in anti-counterfeiting applications. Summary of the invention

[0004] The present invention aims to overcome the defects of the prior art and provide a long afterglow anti-counterfeiting ink composition.

[0005] Another object of the present invention is to provide a method for preparing the long afterglow anti-counterfeiting ink composition.

[0006] The technical solution of the present invention is as follows:

[0007] A long afterglow anti-counterfeiting ink composition is prepared from long afterglow luminescent nano powder and thermoplastic compound resin, wherein the ratio of the long afterglow luminescent nano powder to the thermoplastic compound resin is 1:2-10;

[0008] The excitation light of the long afterglow luminescent nanopowder is ultraviolet light and / or visible light, the emission wavelength is 500-530nm, and it has a cyan, green or yellow-green long afterglow;

[0009] The thermoplastic compound resin has a solid content of 30-50% and a softening point of 80-130°C, and includes at least one of ternary chloroacetic acid resin, polyester resin, aldehyde ketone resin, polystyrene, epoxy resin, petroleum resin, chlorinated polypropylene resin, polyurethane resin, rosin resin, and polyamide resin.

[0010] In some possible implementations, the long afterglow luminescent nanopowder is a carbon dot-melamine complex.

[0011] In some possible implementations, the carbon source of the carbon dot-melamine composite is at least one of m-phenylenediamine, acridine yellow and acridine orange.

[0012] In some possible implementations, the thermoplastic compound resin is compounded from polyurethane resin, polystyrene resin and chloroacetic acid resin.

[0013] In some possible implementations, the ratio of acrylic resin, polychlorinated resin and polyurethane resin is 5:1.25:1.25.

[0014] In some possible implementations, the particle size of the long afterglow luminescent nanopowder is less than 800 mesh.

[0015] In some possible implementations, the method for preparing the long afterglow luminescent nanopowder includes:

[0016] A. mixing a carbon source, a phosphate of the carbon source and ethanol, subjecting the mixture to a hydrothermal reaction at 180° C. for 12 h, centrifuging and filtering to obtain a carbon dot filtrate, wherein the carbon source is at least one of m-phenylenediamine, acridine yellow and acridine orange;

[0017] B. Mix the carbon dot filtrate, melamine, water and ethanol, and perform hydrothermal stirring reaction at 150-250° C. for 3 h. Filter and remove the solvent to obtain the afterglow luminescent nanopowder.

[0018] In some possible implementations, the molar ratio of the carbon source to the phosphate of the carbon source in step A is 1:10-40.

[0019] In some possible implementations, the mass volume ratio of the carbon dot filtrate, melamine, water and ethanol in step B is 2 mL: 1.5 g: 15 mL: 5 mL.

[0020] The method for preparing the long afterglow anti-counterfeiting ink composition comprises: uniformly mixing the long afterglow luminescent nano powder and the thermoplastic compound resin.

[0021] The beneficial effects of the present invention are:

[0022] 1. The invention is simple to make and easy to identify for anti-counterfeiting, expands the capacity of encrypted information, is innovative and environmentally friendly, and invents a tunable multiple encryption method. By regulating the luminescence properties of long afterglow luminescent nanopowders, multiple information encryption anti-counterfeiting applications are realized. It has profound research significance and broad application prospects for avoiding the interference of fluorescence on anti-counterfeiting applications and expanding anti-counterfeiting encryption forms.

[0023] 2. The long afterglow luminescent nanopowder of the present invention can replace traditional luminescent materials, reduce costs, be simple to prepare, and be green and environmentally friendly. It integrates long afterglow, multi-color luminescence and stimulating luminescence, and is expected to develop into a new generation of environmentally friendly multi-dynamic anti-counterfeiting, high-capacity and high-resolution, environmentally friendly optical anti-counterfeiting materials.

[0024] 3. The long afterglow luminescent nanopowder of the present invention can be used in the ink composition to realize reusable and tunable dynamic anti-counterfeiting application; the dual color can enhance the visual anti-counterfeiting effect; it can be excited by ultraviolet light source and / or visible light source to meet the requirements of concealed, portable and easy anti-counterfeiting identification. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 These are digital photos of three different colors of long afterglow luminescent nanopowders prepared in Examples 1-3 under visible light and ultraviolet light, from left to right they are long afterglow luminescent nanopowders A, B, and C;

[0026] Figure 2 The afterglow excitation spectra (a) and emission spectra (b) of three different colors of long afterglow luminescent nanopowders A, B, and C prepared in Examples 1-3 in the visible light band, wherein MPDCDs-MA represents long afterglow luminescent nanopowder A or long afterglow anti-counterfeiting ink composition A, AYCDs-MA represents long afterglow luminescent nanopowder B or long afterglow anti-counterfeiting ink composition B, and AOCDs-MA represents long afterglow luminescent nanopowder C or long afterglow anti-counterfeiting ink composition C, the same below;

[0027] Figure 3 The long afterglow luminescent powders A, B and C prepared in Examples 1-3 are mixed with polystyrene for coating, and afterglow is visible to the naked eye after drying;

[0028] Figure 4 The afterglow emission spectra of the long afterglow anti-counterfeiting ink compositions A, B, and C prepared in Examples 1-3 in different acid and alkaline environments, (a) is the long afterglow luminescent nanopowder A, (b) is the long afterglow luminescent nanopowder B, and (c) is the long afterglow luminescent nanopowder C;

[0029] Figure 5These are the anti-photobleaching graphs of the long afterglow anti-counterfeiting ink compositions A, B, and C prepared in Examples 1-3, (a) is the long afterglow luminescent nanopowder A, (b) is the long afterglow luminescent nanopowder B, and (c) is the long afterglow luminescent nanopowder C;

[0030] Figure 6 These are photostability diagrams of the long afterglow anti-counterfeiting ink compositions A, B, and C prepared in Examples 1-3, (a) is long afterglow luminescent nanopowder A, (b) is long afterglow luminescent nanopowder B, and (c) is long afterglow luminescent nanopowder C. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is further illustrated and described below through specific implementation modes in combination with the accompanying drawings.

[0033] In Example 1-3, during the preparation process of the long afterglow luminescent nanopowder, it is ground and filtered to a particle size of less than 800 mesh. This step is mainly to make the ink smoother and improve the printing quality. However, the particle size does not affect the long afterglow characteristics of the long afterglow luminescent nanopowder and should not be regarded as a limitation to the technical solution.

[0034] Example 1: Preparation of long afterglow anti-counterfeiting ink composition A

[0035] (1) Preparation of long afterglow luminescent nanopowder A:

[0036] A. Add a mixture of m-phenylenediamine (MPD), m-phenylenediamine phosphate and ethanol into a reaction container, hydrothermally react at 180° C. for 12 hours, centrifuge and filter to obtain a carbon dot filtrate; wherein the molar ratio of m-phenylenediamine to m-phenylenediamine phosphate is 1:40;

[0037] B. Add 1.5 g melamine, 5 mL ethanol and 15 mL water to 2 mL of the above carbon dot filtrate, mix, heat at 200°C with stirring for 3 h, grind to 800 mesh, filter, and obtain long afterglow luminescent nanopowder A. Figure 1 As shown, the long afterglow luminescent nanopowder A is a yellow powder under a fluorescent lamp and exhibits a blue-green fluorescence under ultraviolet light radiation.

[0038] (2) Preparation of thermoplastic composite resin: polyurethane resin U335, polystyrene resin PS525 and chloroacetic acid resin VA5178 in a mass ratio of 5:1.25:1.25 are softened at 80-130°C to prepare a thermoplastic composite resin with a solid content of 40% and a softening point of 90°C;

[0039] (3) Preparation of long afterglow anti-counterfeiting ink composition A: The long afterglow luminescent nanopowder A and the thermoplastic composite resin are mixed in a mass ratio of 1:1 to 1:10, and the mixture is mixed and shaken with an oscillator to obtain the long afterglow anti-counterfeiting ink composition A.

[0040] Example 2: Preparation of long afterglow anti-counterfeiting ink composition B

[0041] (1) Preparation of long afterglow luminescent nanopowder B:

[0042] A. Add a mixture of acridinium yellow (AY), acridinium yellow phosphate and ethanol into a reaction container, hydrothermally react at 180°C for 12 hours, centrifuge and filter to obtain a carbon dot filtrate; wherein the molar ratio of acridinium yellow to acridinium yellow phosphate is 1:40;

[0043] B. Add 1.5g melamine, 5mL ethanol and 15mL water to 2mL of the above carbon dot filtrate, mix, heat at 200℃ and stir for 3h, grind to 800 mesh, filter, and obtain long afterglow luminescent nanopowder B (AYCDs-MA). Figure 1 As shown, the long afterglow luminescent nanopowder B is a yellow powder under a fluorescent lamp and exhibits yellow-white fluorescence under ultraviolet light radiation.

[0044] (2) Preparation of thermoplastic composite resin: polyurethane resin U335, polystyrene resin PS525 and vinyl chloride resin VA5178 in a mass ratio of 5:1.25:1.25 are softened at 80-130°C to prepare a thermoplastic composite resin with a solid content of 40% and a softening point of 90°C;

[0045] (3) Preparation of long afterglow anti-counterfeiting ink composition B: The long afterglow luminescent nanopowder B and the thermoplastic composite resin are mixed in a mass ratio of 1:5, and the mixture is mixed and shaken with an oscillator to obtain the long afterglow anti-counterfeiting ink composition B.

[0046] Example 3: Preparation of long afterglow anti-counterfeiting ink composition C

[0047] (1) Preparation of long afterglow luminescent nanopowder C:

[0048] A. Add acridine orange (A0), acridine orange phosphate and ethanol into a reaction container, hydrothermally react at 180° C. for 12 h, centrifuge and filter to obtain a carbon dot filtrate; wherein the molar ratio of acridine orange to acridine orange phosphate is 1:40;

[0049] B. Add 1.5g melamine, 5mL ethanol and 15mL water to 2mL of the above carbon dot filtrate, mix, heat at 200℃ and stir for 3h, grind to 800 mesh, filter, and obtain long afterglow luminescent nanopowder C (AOCDs-MA). Figure 1 As shown, the long afterglow luminescent nanopowder C is orange powder under fluorescent light and exhibits yellow-green fluorescence under ultraviolet light radiation.

[0050] (2) Preparation of thermoplastic composite resin: polyurethane resin U335, polystyrene resin PS525 and vinyl chloride resin VA5178 in a mass ratio of 5:1.25:1.25 are softened at 80-130°C to prepare a thermoplastic composite resin with a solid content of 40 wt% and a softening point of 90°C;

[0051] (3) Preparation of long afterglow anti-counterfeiting ink composition C: The long afterglow luminescent nanopowder C and the thermoplastic composite resin are mixed in a mass ratio of 1:5, and the mixture is mixed and shaken with an oscillator to obtain the long afterglow anti-counterfeiting ink composition C.

[0052] Example 4: Optical response of the long afterglow anti-counterfeiting ink composition on different printed substrates

[0053] The long afterglow anti-counterfeiting ink compositions A and B prepared in Example 1 and Example 2 were respectively printed on two common label papers (long afterglow anti-counterfeiting ink composition A was printed on white companion label paper, and long afterglow anti-counterfeiting ink composition B was printed on sub-silver label paper), and irradiated with fluorescent lamps and ultraviolet lamps (365nm) respectively. After turning off the light source, clear two-dimensional code patterns could be seen, indicating that the long afterglow anti-counterfeiting ink composition can be applied on different printing substrates and can avoid fluorescence interference on printing substrates with fluorescent reactions, thereby achieving multiple encryption and meeting various printing needs.

[0054] Example 5: Optical properties of long afterglow luminescent nanopowders in the visible band

[0055] This example characterizes the optical properties of the long afterglow luminescent nanopowders A, B, and C obtained in Examples 1 to 3. Among them, the scanning speed is preferably 240nm / min; the excitation slit ratio to the emission slit is preferably 5nm:10nm; the response time is preferably 2s; the extension time is preferably 0s; and the PMT voltage is preferably 700V.

[0056] like Figure 3 As shown, the best optical response excitation wavelengths corresponding to the three long afterglow luminescent nanopowders A, B and C are 470nm, 473nm and 500nm, and the optical response emission wavelengths are 500nm, 510nm and 535nm respectively.

[0057] Example 6: Afterglow time visible to naked eyes of the long afterglow anti-counterfeiting ink composition

[0058] The long afterglow luminescent nanopowders A, B and C prepared in Examples 1-3 were mixed with 40 wt% of polystyrene to obtain a long afterglow anti-counterfeiting ink. After irradiation with a mobile phone flashlight (visible light) for 10 seconds, the light source was turned off. Figure 4As shown, A emits cyan for several seconds, B emits green for several seconds, and C emits yellow-green for several seconds. The three materials will also emit afterglow for several seconds after the visible light irradiation is turned off. The three long afterglow anti-counterfeiting inks generally have an afterglow of about 8s after ultraviolet light excitation, and generally have an afterglow of about 4s under visible light excitation.

[0059] Example 7: Luminescence of the long afterglow anti-counterfeiting ink composition in an acidic and alkaline environment

[0060] Long afterglow anti-counterfeiting ink compositions may encounter various solvent interferences in actual anti-counterfeiting applications. If the performance of the long afterglow anti-counterfeiting ink compositions is affected, the application will be affected. In this example, the long afterglow anti-counterfeiting ink compositions A, B, and C prepared in Examples 1-3 were transferred onto label paper, and then water, sulfuric acid (pH=2), and sodium hydroxide alkaline solution (pH=9) were dripped onto the surface of the label paper, respectively, to observe the afterglow luminescence after irradiation with ultraviolet light. Figure 5 As shown in Figure (a), the afterglow of the long afterglow anti-counterfeiting ink composition A is greatly affected by acid and alkali, but the afterglow can still be observed; the long afterglow anti-counterfeiting ink compositions B and C characterized by (b) and (c) are stable in luminescence and are not easily affected by acid and alkali environments. This shows that the long afterglow anti-counterfeiting ink compositions prepared in Examples 1-3 can be used for information anti-counterfeiting in actual production and life and extreme environments.

[0061] Example 8: Long afterglow anti-counterfeiting ink composition resists light interference

[0062] The photobleaching resistance of the long afterglow luminescent nanopowders A, B, and C prepared in Examples 1-3 was tested: a certain amount of long afterglow luminescent nanopowders A, B, and C were placed in the powder sample slots, and irradiated continuously for 60 minutes under a 360nm xenon lamp light source. The afterglow spectra of the long afterglow luminescent nanopowders A, B, and C before and after irradiation were measured to explore the effect of ultraviolet light irradiation time on the afterglow intensity. The experimental results are as follows: Figure 5 As shown, long-term continuous illumination does not affect the optical properties of the material, and the optical properties of the long afterglow anti-counterfeiting ink compositions A and B are stable.

[0063] The photostability of the long afterglow anti-counterfeiting ink compositions A, B, and C was tested: labels were printed with the long afterglow anti-counterfeiting ink compositions A, B, and C and placed in the air for 50 days, and the afterglow spectra were measured every 10 days. The results are as follows: Figure 6 It can be seen that the afterglow intensity of the three changed little within 50 days, indicating that repeated light stimulation does not affect the optical properties of the long afterglow anti-counterfeiting ink composition, and the long afterglow anti-counterfeiting ink compositions A and B can be reused.

[0064] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A long afterglow anti-counterfeiting ink composition, characterized in that: It is prepared from long afterglow luminescent nano powder and thermoplastic compound resin, and the mass ratio of the long afterglow luminescent nano powder to the thermoplastic compound resin is 1:2-10; The excitation light of the long afterglow luminescent nanopowder is ultraviolet light and / or visible light, the emission wavelength is 500-530nm, and it has a cyan, green or yellow-green long afterglow; The thermoplastic compound resin has a solid content of 30-50% and a softening point of 80-130°C, and includes at least one of ternary chloroacetic acid resin, polyester resin, aldehyde ketone resin, polystyrene, epoxy resin, petroleum resin, chlorinated polypropylene resin, polyurethane resin, rosin resin, and polyamide resin.

2. A long afterglow anti-counterfeiting ink composition as claimed in claim 1, characterized in that: The long afterglow luminescent nano powder is a carbon dot-melamine complex.

3. A long afterglow anti-counterfeiting ink composition as claimed in claim 2, characterized in that: The carbon source of the carbon dot-melamine composite is at least one of m-phenylenediamine, acridine yellow and acridine orange.

4. The long afterglow anti-counterfeiting ink composition according to claim 1, characterized in that: The thermoplastic compound resin is compounded from polyurethane resin, polystyrene resin and chloroacetic acid resin.

5. The long afterglow anti-counterfeiting ink composition according to claim 4, characterized in that: The mixing ratio of the acrylic resin, the polychlorinated resin and the polyurethane resin is 55:1.255:1.

255.

6. A long afterglow anti-counterfeiting ink composition as claimed in claim 1, characterized in that: The particle size of the long afterglow luminescent nano powder is less than 800 meshes.

7. A long afterglow anti-counterfeiting ink composition according to any one of claims 1 to 6, characterized in that: The preparation method of the long afterglow luminescent nano powder comprises: A. mixing a carbon source, phosphoric acid of the carbon source and ethanol, subjecting the mixture to a hydrothermal reaction at 180° C. for 12 h, centrifuging and filtering to obtain a carbon dot filtrate, wherein the carbon source is at least one of m-phenylenediamine, acridine yellow and acridine orange; B. Mix the carbon dot filtrate, melamine, water and ethanol, and perform hydrothermal stirring reaction at 150-250° C. for 3 h. Filter and remove the solvent to obtain the afterglow luminescent nanopowder.

8. The long afterglow anti-counterfeiting ink composition according to claim 7, characterized in that: In step A, the molar ratio of the carbon source to the phosphoric acid of the carbon source is 1:10-40.

9. The long afterglow anti-counterfeiting ink composition according to claim 7, characterized in that: The mass volume ratio of the carbon dot filtrate, the melamine, the water and the ethanol in step B is 2 mL:1.5 g:15 mL:5 mL.

10. A method for preparing a long afterglow anti-counterfeiting ink composition according to any one of claims 1 to 9, characterized in that: include: The long afterglow luminescent nano powder and the thermoplastic compound resin are mixed evenly to obtain the product.

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