Laser anti-counterfeiting mark and preparation method thereof
By introducing a multi-layer structure and an organozirconium complex microcapsule design into the laser anti-counterfeiting label, the problems of material elastic recovery and yellowing of the protective layer during the molding process were solved, improving the anti-counterfeiting performance and stability of the holographic pattern layer, and realizing a high-precision and long-term stable laser anti-counterfeiting label.
Patent Information
- Application Number
- CN202511081995.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-04
- Publication Date
- 2025-11-07
AI Technical Summary
Existing laser anti-counterfeiting labels suffer from problems during the molding process, such as reduced information reproducibility due to elastic recovery, easy oxidation and yellowing of the protective layer, and insufficient refractive index of the holographic pattern layer, making it difficult to meet the requirements of anti-counterfeiting verification.
The material employs a multi-layer structure design, including a substrate layer, a release layer, a protective layer, a holographic pattern layer, an information digital layer, an aluminum plating layer, and an adhesive backing layer. By introducing microcapsules containing organic zirconium complexes and a base material with a specific composition into the holographic pattern layer, the microcapsules trigger a secondary cross-linking reaction during the molding process, inhibiting elastic recovery. Furthermore, fluorine compounds are used to enhance the material's antioxidant properties, thereby constructing a high-refractive-index network structure.
It improves the anti-counterfeiting performance and long-term stability of the holographic pattern layer, enhances the visible light refractive index and clarity of the pattern, prevents yellowing, and achieves high-precision and long-term stable laser anti-counterfeiting labels.
Smart Images
Figure CN120913488A_ABST
Abstract
Description
TECHNICAL FIELD
[0002] The present application relates to the technical field of anti-counterfeiting marking, in particular to a laser anti-counterfeiting mark and a preparation method thereof. BACKGROUND
[0003] The laser anti-counterfeiting mark is commonly used in the packaging of commodities and has no influence on the patterns on the packaging materials of the commodities, but can clearly display the holographic patterns and characters that cannot be counterfeited, thereby improving the ornamental properties of the outer packaging of the commodities and achieving the anti-counterfeiting properties. The laser anti-counterfeiting mark plays a key role in the laser holographic anti-counterfeiting pattern in the holographic pattern layer, and the coating layer is pressed on the embossed pattern on the metal mold through thermal deformation. However, the holographic pattern layer formed by the thermoplastic polymer in the prior art still has some problems, such as the information multiplicity is reduced due to the elastic recovery in the heating and molding process, or the information layer may also be deformed to cause fogging, or the protective layer covering the holographic pattern layer is prone to yellowing, so that the laser holographic anti-counterfeiting pattern cannot be clearly or completely observed, or the refractive index of the holographic pattern layer to visible light is too low to meet the demand for observation to distinguish the authenticity. SUMMARY
[0004] The main purpose of the present application is to develop a laser anti-counterfeiting mark and a preparation method thereof.
[0005] To achieve the above-mentioned purpose, the present application provides a laser anti-counterfeiting mark, which comprises a substrate layer, a release layer, a protective layer, a holographic pattern layer, an information digital layer, an aluminum plating layer and a back adhesive layer which are sequentially stacked from top to bottom; wherein the holographic pattern layer is provided with a holographic anti-counterfeiting pattern, and the holographic pattern layer comprises a base material and microcapsules dispersed in the base material, and the holographic pattern layer comprises 5wt%-10wt% of microcapsules; the microcapsules comprise a core and a shell layer, the core comprises an organic zirconium complex, and the raw materials for preparing the organic zirconium complex comprise a zirconium salt, lactic acid and triethanolamine. The base material comprises the following raw materials by weight: isocyanate acrylate: 8-14 parts; diphenylmethane bismaleimide: 5-8 parts; hyperbranched polyurethane acrylate: 10-20 parts; trifluoroethyl glycidyl ether: 3-6 parts; epoxy resin: 12-18 parts; acrylate monomer: 20-40 parts; initiator: 0.5-1 part; and solvent: 30-60 parts.
[0006] In an embodiment, the acrylate monomer comprises at least two of isobutyl acrylate, methyl cyclohexyl acrylate, glycidyl methacrylate, styrene, 2-ethylhexyl acrylate and methacrylic acid.
[0007] In an embodiment, the zirconium salt comprises zirconium oxychloride hydrate.
[0008] In an embodiment, the preparation method of the organic zirconium complex comprises the following steps: The zirconium oxychloride hydrate is stirred and dissolved in deionized water to obtain a first solution; the lactic acid is dissolved in deionized water, and a 5wt% sodium hydroxide solution is added dropwise to a pH of 4.0-4.5 to obtain a second solution; the second solution is added dropwise into the first solution while maintaining a temperature of 35-50°C, and stirred and reacted for 0.5-1h, then a triethanolamine solution is added dropwise into the reaction system, and stirred and reacted for 1-2h, concentrated, precipitated with anhydrous ethanol, washed, and dried to obtain the organic zirconium complex.
[0009] In an embodiment, the weight ratio of the zirconium oxychloride hydrate, lactic acid and triethanolamine is (28-35):(13-20):(11-15).
[0010] In an embodiment, the preparation method of the microcapsule comprises the following steps: The organic zirconium complex and the surfactant are dissolved in deionized water to obtain a 10wt%-30wt% inner core solution; an 8wt%-10wt% urea aqueous solution is prepared, then a 30wt%-35wt% formaldehyde aqueous solution is added, mixed, and then an inner core solution is added dropwise into the shell solution while stirring and reacting, and the reaction is carried out at 55-60°C for 2-3h, then a 5wt% sodium hydroxide solution is added to neutralize the solution, the lower precipitate is removed by centrifugation, and dried to obtain the microcapsule.
[0011] In an embodiment, the protective layer comprises the following raw materials by weight percentage: Phenolic resin: 20wt%-30wt%; furan methanol: 3wt-7wt%; acetyl ferrocene: 1.5wt% 4wt%; silane coupling agent: 1wt%-2wt%; organic tin: 0.5wt%-1wt%; and the balance is an ethanol solution.
[0012] In an embodiment, the information digital layer is digital information and / or graphic text printed on the holographic pattern layer; the digital information comprises at least one of a bar code, a two-dimensional code, and a special code.
[0013] In an embodiment, the thickness of the holographic pattern layer is 3-10μm.
[0014] In an embodiment, the thickness of the protective layer is 20-30μm.
[0015] The application also provides a preparation method of the laser anti-counterfeiting mark, comprising the following steps: The application provides a laser anti-counterfeiting mark and a preparation method thereof. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description only represent some of the embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the drawings shown.
[0017] Figure 1 The laser anti-counterfeiting mark in Example 1 in the present application is shown in the electron microscope photograph. The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION
[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments only represent some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort belong to the scope of protection of the present application.
[0019] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between the components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.
[0020] In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can be explicitly or implicitly included at least one of the features. In addition, if "and / or" or "and / or" appears throughout the text, it means that the three parallel schemes include the A scheme, or the B scheme, or the A and B schemes. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.
[0021] In the prior art, the laser anti-counterfeiting mark forms a holographic pattern layer through a thermoplastic polymer, but the information complexity is reduced due to the elastic recovery during the molding process. The protective layer material is easy to oxidize and yellow under high temperature environment, affecting the observation effect of the holographic pattern. The refractive index of the traditional holographic pattern layer is insufficient, resulting in poor visible light reflection effect, which is difficult to meet the anti-counterfeiting verification demand. For example, in a high temperature and high humidity storage environment, the anti-counterfeiting mark on the commodity packaging is easy to appear fogging and pattern blurring phenomenon.
[0022] In order to solve the above technical problems, first of all, it is necessary to analyze the deformation mechanism of the holographic pattern layer, and it is found that the molecular chain of the thermoplastic material will shrink after molding. By introducing the microcapsule structure of the releasable curing agent, the secondary crosslinking reaction is triggered to inhibit the elastic recovery during the molding process. Secondly, in view of the yellowing problem of the protective layer, the anti-oxidation performance of the material is improved by selecting fluorine-containing compounds. Finally, by adjusting the component ratio of the base material, a high refractive index network structure is constructed.
[0023] The present application provides a kind of laser anti-counterfeiting mark, the laser anti-counterfeiting mark includes substrate layer, release layer, protective layer, holographic pattern layer, information digital layer, aluminized layer and back adhesive layer from top to bottom sequentially stacked;Wherein, the holographic pattern layer is equipped with holographic anti-counterfeiting pattern, the holographic pattern layer includes base material and microcapsule dispersed in the base material, and the holographic pattern layer includes 5wt%~10wt% microcapsule;The microcapsule includes core and shell, the core includes organic zirconium complex, and the raw materials of the organic zirconium complex include zirconium salt, lactic acid and triethanolamine; The base material includes the following raw materials by weight: isocyanate acrylate: 8~14 parts;Diphenylmethane bismaleimide: 5~8 parts;Hyperbranched polyurethane acrylate: 10~20 parts;Trifluoroethyl glycidyl ether: 3~6 parts;Epoxy resin: 12~18 parts;Acrylate monomer: 20~40 parts;Initiator: 0.5~1 part;And, solvent: 30~60 parts.
[0024] It should be noted that the microcapsule refers to an encapsulation body with a core-shell structure, the inner core contains a decomposable metal complex, and the shell layer is prepared by using urea-formaldehyde resin. The structure is broken by heat during the molding process, releasing the active substance. The organic zirconium complex refers to a complex formed by zirconium ions and organic ligands, which can be prepared by reacting zirconium oxychloride with lactic acid and triethanolamine in an aqueous phase. After the substance is decomposed, nano-zirconia particles are generated, and amine compounds are released at the same time.
[0025] Specifically, during the molding process, the shell layer of the microcapsule at the corresponding position of the holographic anti-counterfeiting pattern of the holographic pattern layer is broken by heat and force, releasing the organic zirconium complex. The nano-zirconia particles generated by the decomposition of the complex are filled in the crosslinked network of the base material, improving the hardness and refractive index of the material. The released amine compounds undergo ring-opening reaction with unreacted epoxy groups in the base material, forming new crosslinking points to inhibit elastic recovery. The fluorine element in the trifluoroethyl glycidyl ether forms a dense structure in the protective layer, blocking the penetration of oxygen and preventing yellowing. The hyperbranched polyurethane acrylate and isocyanate acrylate work together to build a rigid skeleton with high crosslinking density.
[0026] In an embodiment, the acrylate monomers include at least two of isobutyl acrylate, methyl cyclohexyl acrylate, glycidyl methacrylate, styrene, 2-ethylhexyl acrylate, and methacrylic acid.
[0027] It should be noted that the combination of at least two acrylate monomers with different functional groups and molecular structures improves the hardness, crosslinking density, and stability of the prepared polymer. The stable three-dimensional network structure formed by the interaction between the molecular chains can inhibit the elastic recovery of the thermoplastic material to some extent, and also improves the replication accuracy and edge definition of the anti-counterfeiting pattern. The existing laser anti-counterfeiting mark holographic pattern layer mostly uses a single acrylate monomer or a general copolymer, which has the problem of high deformation recovery rate after molding and insufficient heat resistance.
[0028] In an embodiment, the zirconium salt includes zirconium oxychloride hydrate.
[0029] It should be noted that zirconium oxychloride hydrate refers to a zirconium oxychloride compound containing crystal water, which can be specifically implemented by ZrOCl2•8H2O. In an aqueous system, it can release Zr 4+ ions and form a stable coordination structure with organic ligands. This compound can coordinate with the carboxyl groups in lactic acid and the hydroxyl and amino groups in triethanolamine, thereby constructing the organic zirconium complex core.
[0030] In an embodiment, the preparation method of the organic zirconium complex includes the following steps: The zirconium oxychloride hydrate is dissolved in deionized water to prepare a first solution; the lactic acid is dissolved in deionized water, and 5wt% sodium hydroxide solution is added dropwise to pH 4.0-4.5 to prepare a second solution; the second solution is added dropwise into the first solution while maintaining the temperature at 35-50°C, and stirred for 0.5-1h, then triethanolamine solution is added dropwise into the reaction system, and stirred for 1-2h, concentrated, precipitated with anhydrous ethanol, washed, and dried to obtain the organic zirconium complex.
[0031] In a specific embodiment, the weight ratio of zirconium oxychloride hydrate, lactic acid and triethanolamine is (28-35):(13-20):(11-15).
[0032] It should be noted that controlling the pH value of the second solution to 4.0-4.5 can avoid the hydrolysis of zirconium salt to generate zirconium hydroxide precipitate, while ensuring the effective coordination of lactic acid and zirconium ions. The reaction temperature of 35-50°C promotes the coordination reaction rate and inhibits the side reaction. The triethanolamine solution refers to a solution prepared by mixing triethanolamine and deionized water in a certain proportion, and the hydroxyl and amino groups in the molecule act as polydentate ligands to form a stable complex structure with zirconium ions. During the reaction, pH adjustment avoids excessive lactic acid leading to over-acidification of the system, preventing zirconium ion precipitation; the step-by-step dropwise addition strategy ensures that the ligands bind to zirconium ions in sequence, reducing competitive coordination interference; the ethanol precipitation method promotes the precipitation of the complex by reducing the polarity of the solution, while removing unreacted ionic impurities. The purified complex does not contain acidic residues, avoiding the yellowing problem of the protective layer caused by the catalytic oxidation of acidic substances. By controlling the proportion of raw materials, the coordination vacancies of zirconium ions are fully occupied by lactic acid and triethanolamine, forming a complex core.
[0033] In an embodiment, the preparation method of the microcapsule comprises the following steps: The organic zirconium complex and the surfactant are dissolved in deionized water to prepare an 10-30wt% core solution, which is ready for use; an 8-10wt% urea aqueous solution is prepared, then a 30-35wt% formaldehyde aqueous solution is added, and after mixing, a shell solution is prepared; the core solution is added dropwise into the shell solution while stirring, and the reaction is carried out at 55-60°C for 2-3h, 5wt% sodium hydroxide solution is added to neutralize the solution, the lower precipitate is removed by centrifugation, and dried to obtain the microcapsule.
[0034] It can be understood that the shell solution refers to a prepolymer system of urea and formaldehyde, and the core solution stably disperses the organic zirconium complex through the action of a surfactant to form uniform core droplets. The urea and formaldehyde in the shell solution are pre-polymerized to form low-molecular-weight condensates at a specific concentration, and after the core solution is added dropwise, the shell pre-polymers are adsorbed on the surface of the core under the action of stirring, and an integrated coating is formed through gradual condensation. The reaction temperature and time are controlled to ensure that the condensation reaction proceeds sufficiently, and the shell is not too thin or broken. Through the above technical solution, the present application realizes the uniform dispersion of the microcapsule core material and the efficient coating of the shell, and improves the structural stability of the microcapsule in the molding process. By controlling the reaction conditions and neutralization treatment, the degradation of the shell is avoided, and the integrity of the microcapsule is ensured in subsequent processing, thereby improving the anti-counterfeiting performance and durability of the holographic pattern layer.
[0035] In an embodiment, the protective layer comprises the following raw materials by weight percentage: Phenolic resin: 20wt%-30wt%; furfuryl alcohol: 3wt-7wt%; acetyl ferrocene: 1.5wt% 4wt%; silane coupling agent: 1wt%-2wt%; organic tin: 0.5wt%-1wt%; and the balance is an ethanol solution.
[0036] Acetyl ferrocene refers to a ferrocene derivative, which can be specifically implemented by acetyl-substituted ferrocene, and acts as an antioxidant to inhibit yellowing caused by high-temperature oxidation of phenolic resin by capturing free radicals. The silane coupling agent refers to an organic compound containing a siloxane group, which can be specifically implemented by γ-aminopropyl triethoxysilane, and acts as an interface modifier to form a chemical bond with the substrate surface through silicon hydroxyl to improve adhesion. The organic tin refers to an organic compound containing tin element, which can be specifically implemented by dibutyltin dilaurate, and acts as a catalyst to promote the cross-linking reaction of phenolic resin and furfuryl alcohol. The ethanol solution refers to a mixed system with ethanol as the main solvent, which can be specifically implemented by an ethanol aqueous solution with a concentration range of 50wt%-70wt%, and acts as a dispersion medium to adjust the viscosity of the coating and promote the uniformity of film formation.
[0037] By adopting the technical scheme, the phenolic resin and furan methanol occur polycondensation reaction under the catalysis of organic tin to form a crosslinked network structure, so that the protective layer maintains dimensional stability at the mold pressing temperature, and damage of the holographic pattern layer caused by thermal deformation is avoided. The acetyl ferrocene captures free radicals generated by the phenolic resin during high-temperature mold pressing, blocks the oxidation chain reaction, and thus inhibits the yellowing phenomenon of the protective layer. The silane coupling agent forms chemical bonding with the surface of the holographic pattern layer through silicon hydroxyl groups, enhances the interlayer bonding force, and prevents the protective layer from peeling off from the holographic pattern layer during mold pressing. The application realizes the anti-yellowing performance of the protective layer under high-temperature mold pressing conditions, ensures the optical visibility of the holographic pattern layer, and at the same time, through optimization of the crosslinking density and the interfacial bonding force, the protective layer has sufficient mechanical strength to support the mold pressing process.
[0038] In an embodiment, the information digital layer is digital information and / or graphic text printed on the holographic imaging layer; the digital information includes at least one of a bar code, a two-dimensional code and special digital information.
[0039] It can be understood that the information digital layer is obtained by directly applying ink containing digital information to the surface of the holographic pattern layer through a printing device after the holographic pattern layer is cured, and provides standardized data reading and encrypted information storage functions. The superposition of multiple information layers enables the anti-counterfeiting mark to simultaneously have optical feature recognition and digital verification functions, and the information of each layer forms a cross-verification relationship, thereby realizing the multi-dimensional information verification capability of the anti-counterfeiting mark, solving the problem that a single holographic pattern is easily copied, and significantly improving the difficulty of imitation.
[0040] In an embodiment, the thickness of the holographic pattern layer is 3-10 microns.
[0041] In an embodiment, the thickness of the protective layer is 20-30 microns.
[0042] It can be understood that the thickness range of the holographic pattern layer refers to the vertical direction size of the coating layer forming the holographic anti-counterfeiting pattern after curing. When the thickness of the holographic pattern layer is less than 3 microns, the coating layer cannot fully fill the microstructure of the holographic plate during mold pressing, resulting in missing of pattern details. When the thickness exceeds 10 microns, internal stress caused by shrinkage during curing will cause elastic recovery of the coating layer, causing deformation of the embossed pattern. The thickness range of the protective layer refers to the vertical direction size of the transparent coating layer covering the surface of the holographic pattern layer. When the thickness of the protective layer exceeds 30 microns, light scattering occurs during transmission, affecting the clarity of the holographic pattern. By limiting the thickness range of the holographic pattern layer and the protective layer, high-fidelity transfer of the holographic pattern is realized in the mold pressing process, and the service life of the anti-counterfeiting mark is prolonged through the physical barrier effect of the protective layer.
[0043] The application also provides a preparation method of the laser anti-counterfeiting mark. S1, coating a release layer resin on one surface of the cleaned substrate layer, drying, forming a release layer; S2, mixing raw materials for preparing a protective layer in proportion, stirring and reacting, preparing a protective layer coating, coating on the surface of the release layer prepared in step S1, drying, forming a protective layer; S3, pre-dissolving diphenylmethane bismaleimide and epoxy resin respectively, adding hyperbranched polyurethane acrylate, acrylate monomer and isocyanate acrylate in the reaction container in turn, stirring, then adding trifluoroethyl glycidyl ether, stirring under heating, then adding microcapsules, pre-dissolved diphenylmethane bismaleimide and pre-dissolved epoxy resin, stirring, adding an initiator, stirring, vacuum degassing, preparing a holographic pattern layer coating, coating on the surface of the protective layer prepared in step S2, drying, ultraviolet irradiation for curing, preparing a to-be-printed holographic pattern layer; S4, molding the to-be-printed holographic pattern layer prepared in step S3 under the condition of double hard rollers, wherein the holographic plate molds the to-be-printed holographic pattern layer, and the other hard roller presses the substrate layer, to prepare a holographic pattern layer; S5, sequentially forming an information digital layer, an aluminum plating layer and an adhesive layer on the surface of the holographic pattern layer prepared in step S4, to complete the preparation.
[0044] It should be noted that the double hard roller molding refers to synchronously applying pressure by two hard rollers, which can be achieved by cooperating a holographic plate roller with a substrate support roller, and the holographic plate roller is used to print the pattern, and the substrate support roller is used to provide counter pressure to avoid elastic deformation of the material during the molding process.
[0045] Through the above technical solution, the application solves the problem of reduced pattern replication caused by elastic recovery of the material during the molding process, and suppresses deformation by synchronously applying pressure by double hard rollers; the anti-aging performance is improved by optimizing the protective layer formula; the defect of insufficient refractive index of the holographic pattern layer is improved, and finally the preparation of high-precision and high-stability laser anti-counterfeiting marks is realized.
[0046] In a specific embodiment, in step S4, the molding temperature is 160-200℃, the molding pressure is 0.5-1MPa, and the speed is 20-35m / min.
[0047] The molding temperature refers to the environmental temperature during hot stamping by a metal mold on the surface of the holographic pattern layer, which can be achieved by using a segmented temperature control system. The speed refers to the transmission speed of the substrate layer in the molding equipment, which can be achieved by adjusting the roller speed through a variable frequency motor.
[0048] The application is further described through specific embodiments as follows: The raw materials used in the embodiments of the application are commercially available, and the application does not make any limitation on the source of the raw materials.
[0049] Example 1 The laser anti-counterfeiting mark in Example 1 comprises, from top to bottom, a substrate layer, a release layer, a protective layer, a holographic pattern layer, an information digital layer, an aluminum plating layer, and an adhesive layer; The holographic pattern layer comprises 6wt% of microcapsules and a balance of a base material. The microcapsules comprise a shell layer and a core, and the core comprises: zirconium oxychloride hydrate 30g; lactic acid 16g; and triethanolamine 12g.
[0050] The base material comprises: isocyanate acrylate, which is isocyanatoethyl methacrylate 100g; diphenyl methane bismaleimide 50g; hyperbranched polyurethane acrylate, which is H-575PMA 140g; trifluoroethyl glycidyl ether 40g; bisphenol A type epoxy resin 150g; acrylate monomer, which is cyclohexyl acrylate methyl 200g and isobutyl acrylate 100g; initiator, which is Darocur 1173 5g; and solvent, which is ethyl acetate 300g.
[0051] The protective layer comprises: The phenolic resin is Japan Sumitomo PM-9750 300g; furan methanol 50g; acetyl ferrocene 15g; silane coupling agent 15g; organic tin 5g; and 50wt% ethanol solution 615g.
[0052] The preparation method of the microcapsules in Example 1 comprises the following steps: A first solution was prepared by stirring and dissolving 30g of zirconium oxychloride hydrate in 100mL of deionized water while controlling the pH to prevent hydrolysis; a second solution was prepared by dissolving 16g of lactic acid in 20mL of deionized water, adding a 5wt% sodium hydroxide solution dropwise to a pH of 4.0-4.5, and then keeping the temperature at 50°C; the second solution was added dropwise to the first solution, and stirred for 0.5h; then a triethanolamine solution (12g, 10mL) was added dropwise to the reaction system, and stirred for 1h; the volume was concentrated to one-third of the original volume, anhydrous ethanol was added to generate a precipitate, which was washed and dried to obtain an organic zirconium complex; the prepared organic zirconium complex and 1g of sodium dodecylbenzenesulfonate were dissolved in deionized water to obtain a 15wt% core solution, which was prepared for use; a 10wt% urea aqueous solution was prepared, and then a 30wt% formaldehyde aqueous solution was added; after mixing, a shell layer solution was prepared; the core solution was added dropwise to the shell layer solution, and stirred and reacted while adding; the reaction was carried out at 60°C for 2h, a 5wt% sodium hydroxide solution was added to neutralize the solution, the lower precipitate was removed by centrifugation, and dried to obtain the microcapsules.
[0053] The preparation method of the protective layer coating in Example 1 comprises the following steps: The ethanol solution is mixed with the phenolic resin and stirred until completely dissolved. Furfuryl alcohol, acetyl ferrocene and silane coupling agent are added and stirring is continued for 20 min. The organotin catalyst is added and stirred for 10 min to disperse uniformly. Vacuum degassing treatment is performed and the protective layer coating is prepared by standing and aging for 2 h.
[0054] The preparation method of the laser anti-counterfeiting mark in Example 1 includes the following steps: S1, the cleaned PET film is used as a substrate layer, and a silicone resin (DEHESIVE® 920) is coated on one surface of the substrate layer at a dry coating amount of 0.8 g / m 2 , and dried at 90°C to form a release layer; S2, the protective layer coating is coated on the surface of the release layer prepared in step S1, and dried at 60°C to form a protective layer with a dry film thickness of about 21 μm; S3, diphenylmethane bismaleimide and epoxy resin are separately pre-dissolved, and hyperbranched polyurethane acrylate, acrylate monomer and isocyanate acrylate are sequentially added to a light-proof container, stirred at a speed of 300 rpm for 10 min, then trifluoroethyl glycidyl ether is added, stirred at a speed of 600 rpm at 50°C for 20 min, then the temperature is lowered to 40°C, and microcapsules, pre-dissolved diphenylmethane bismaleimide and pre-dissolved epoxy resin are added, stirred for 30 min until uniform, initiator is added, stirred for 10 min, and degassed under vacuum at (-0.1 MPa) for 15 min to prepare a holographic pattern layer coating, which is coated on the surface of the protective layer prepared in step S2, dried, and exposed to ultraviolet light at 80 mW / cm 2 for 20 seconds to prepare a holographic pattern layer with a dry film thickness of about 5 μm to be printed; S4, using a die stamping intaglio integrated machine, the holographic pattern layer to be printed prepared in step S3 is die stamped under double hard roll conditions, wherein a holographic plate die stamps the holographic pattern layer to be printed, and the other hard roll presses the substrate layer, the die stamping temperature is controlled at 170°C, the die stamping pressure is 0.8 MPa, and the vehicle speed is controlled at 20 m / min to prepare the holographic pattern layer; S5, the information digital layer, the aluminum plating layer and the back adhesive layer are sequentially formed on the surface of the holographic pattern layer prepared in step S4, cut, and wound up to complete the preparation.
[0055] Example 2 Example 2 is based on Example 1, with the difference that the holographic pattern layer in the laser anti-counterfeiting mark in Example 2 includes 10 wt% of microcapsules and the balance of base material.
[0056] Example 3 Example 3 is based on Example 1, the difference is that the raw material of the base material in the laser anti-counterfeiting mark in Example 3 is changed to: isocyanate acrylate uses isocyanate methyl acrylate: 140g; diphenyl methane bismaleimide: 80g; hyperbranched polyurethane acrylate uses H-575PMA: 130g; trifluoroethyl glycidyl ether: 60g; bisphenol A type epoxy resin: 120g; acrylate monomer uses 200g of isobutyl acrylate and 100g of glycidyl methacrylate; initiator uses Darocur 1173: 5g; solvent uses ethyl acetate: 300g.
[0057] Comparative Example 1 Comparative Example 1 is based on Example 1, the difference is that the preparation method of the microcapsule of the holographic pattern layer in the laser anti-counterfeiting mark in Comparative Example 1 is changed to: A 15wt% inner core solution was prepared by dissolving a nanometer zirconium oxide sol containing equimolar zirconium oxide, 16g lactic acid, 12g triethanolamine and 1g sodium dodecylbenzenesulfonate in deionized water; a 10wt% urea aqueous solution was prepared, then a 30wt% formaldehyde aqueous solution was added, and after mixing, a shell solution was prepared; the inner core solution was added dropwise to the shell solution while stirring and reacting, and the reaction was carried out at 60°C for 2h; 5wt% sodium hydroxide solution was added until the solution was neutral; the lower precipitate was centrifuged and dried to obtain the microcapsule.
[0058] Comparative Example 2 Comparative Example 2 is based on Example 1, the difference is that the base material of the holographic pattern layer in the laser anti-counterfeiting mark in Comparative Example 2 replaces diphenyl methane bismaleimide with an equal amount of triethylamine.
[0059] Comparative Example 3 Comparative Example 3 is based on Example 1, the difference is that the acetyl ferrocene in the protective layer of the laser anti-counterfeiting mark in Comparative Example 3 is replaced by butylated hydroxyanisole.
[0060] Performance test (1) The yellowing resistance of the protective layer and the holographic pattern layer of the laser anti-counterfeiting mark prepared in Examples 1-3 and Comparative Examples 1-3 was tested according to the standard HG-T 5659-2019 "Optical functional film Yellowing measurement method", and the yellowing index change value was determined.
[0061] (2) The refractive index of the laser anti-counterfeiting mark prepared in the examples and comparative examples at 400nm and 700nm visible light at an incident angle of 55°C was determined using a spectral ellipsometer.
[0062] (3) The laser anti-counterfeiting mark prepared in Example 1 was observed using an electron microscope, and the specific observation results are shown in Figure 1The anti-counterfeiting image in the holographic pattern layer has good display effect.
[0063] The above determination results are shown in Table 1.
[0064] Table 1
[0065] The above merely describes exemplary embodiments of the present application and is not intended to limit the patent scope of the present application. Any equivalent structural transformation made under the technical concept of the present application, or direct / indirect application in other related technical fields, is included in the patent protection scope of the present application.
Claims
1. A laser security marking, characterized in that The laser anti-counterfeiting mark comprises, from top to bottom, a substrate layer, a release layer, a protective layer, a holographic pattern layer, an information digital layer, an aluminum plating layer and an adhesive layer; The holographic pattern layer is provided with a holographic anti-counterfeiting pattern, and comprises a base material and microcapsules dispersed in the base material, and the holographic pattern layer comprises 5wt%-10wt% of the microcapsules; The microcapsules comprise a core and a shell layer, the core comprises an organic zirconium complex, and the organic zirconium complex is prepared from a zirconium salt, lactic acid and triethanolamine; The base material comprises the following raw materials by weight: Isocyanate acrylate: 8-14 parts; diphenyl methane bismaleimide: 5-8 parts; hyperbranched polyurethane acrylate: 10-20 parts; trifluoroethyl glycidyl ether: 3-6 parts; epoxy resin: 12-18 parts; acrylate monomer: 20-40 parts; initiator: 0.5-1 part; and solvent: 30-60 parts.
2. The laser security marking of claim 1, wherein, The acrylate monomer comprises at least two of isobutyl acrylate, methyl cyclohexyl acrylate, glycidyl methacrylate, styrene, 2-ethylhexyl acrylate and methacrylic acid.
3. The laser security mark of claim 1, wherein, The zirconium salt comprises zirconium oxychloride hydrate.
4. The laser anti-counterfeiting label as described in claim 3, characterized in that, The preparation method of the organic zirconium complex comprises the following steps: The zirconium oxychloride hydrate is stirred and dissolved in deionized water to obtain a first solution; lactic acid is dissolved in deionized water, 5wt% sodium hydroxide solution is added dropwise to obtain a second solution with a pH of 4.0-4.5; the second solution is added dropwise into the first solution while maintaining a temperature of 35-50°C, and stirred for 0.5-1h, then triethanolamine solution is added dropwise into the reaction system, and stirred for 1-2h, concentrated, added with anhydrous ethanol to obtain a precipitate, washed, dried to obtain the organic zirconium complex; The weight ratio of the zirconium oxychloride hydrate, lactic acid and triethanolamine is (28-35):(13-20):(11-15).
5. The laser security mark of claim 1, wherein, The preparation method of the microcapsules comprises the following steps: The organic zirconium complex and a surfactant are dissolved in deionized water to obtain a 10wt%-30wt% core solution, which is prepared for use; an 8wt%-10wt% urea aqueous solution is prepared, then a 30wt%-35wt% formaldehyde aqueous solution is added, mixed to obtain a shell layer solution; the core solution is added dropwise into the shell layer solution while stirring, and reacted at 55-60°C for 2-3h, then 5wt% sodium hydroxide solution is added to neutralize the solution, the lower precipitate is removed by centrifugation, and dried to obtain the microcapsules.
6. The laser security mark of claim 1, wherein, The protective layer comprises the following raw materials by weight percentage: Phenolic resin: 20wt%-30wt%; furan methanol: 3wt%-7wt%; acetyl ferrocene: 1.5wt%-4wt%; silane coupling agent: 1wt%-2wt%; organic tin: 0.5wt%-1wt%; and the balance of ethanol solution. The information digital layer is digital information and / or graphic text printed on the holographic imaging layer; the digital information comprises at least one of a bar code, a two-dimensional code and special digital information.
7. The laser security mark of claim 1, wherein, The thickness of the holographic pattern layer is 3-10μm.
8. The laser security mark of claim 1, wherein, And / or, the thickness of the protective layer is 20-30 μm.
9. A method of producing a laser security marking according to any one of claims 1 to 8, characterized in that, The preparation method of the laser anti-fake mark comprises the following steps: S1, coating a release layer resin on one surface of the cleaned base material layer, drying to form a release layer; S2, mixing raw materials for preparing the protective layer in proportion, stirring and reacting to prepare a protective layer coating, coating on the surface of the release layer prepared in the step S1, drying to form a protective layer; S3, pre-dissolving diphenyl methane bismaleimide and epoxy resin respectively, adding hyperbranched polyurethane acrylate, acrylate monomer and isocyanate acrylate in the reaction container in sequence, stirring, then adding trifluoroethyl glycidyl ether, warming and stirring, then adding microcapsules, pre-dissolved diphenyl methane bismaleimide and pre-dissolved epoxy resin, stirring, adding an initiator, stirring, vacuum degassing to prepare a holographic pattern layer coating, coating on the surface of the protective layer prepared in the step S2, drying, ultraviolet irradiation for curing to prepare a to-be-printed holographic pattern layer; S4, performing mold pressing on the to-be-printed holographic pattern layer prepared in the step S3 under the condition of double hard rollers, wherein a holographic plate molds the to-be-printed holographic pattern layer, and the other hard roller presses the base material layer to prepare a holographic pattern layer; S5, sequentially forming an information digital layer, an aluminum plating layer and an adhesive layer on the surface of the holographic pattern layer prepared in the step S4 to complete the preparation.
10. A method of producing a laser security marking according to claim 9, characterized in that, In the step S4, the mold pressing temperature is 160-200 ℃, the mold pressing pressure is 0.5-1 MPa, and the running speed is 20-35 m / min.