Anti-uncovering fragile paper anti-counterfeit label and manufacturing method thereof

Abstract

The invention provides an anti-uncovering fragile paper anti-counterfeit label and a manufacturing method thereof, and relates to the technical field of anti-counterfeit labels. The label comprises a dynamic bonding layer, a fragile paper base material layer, a letterpress printing layer, a grating defect layer, a stress induction layer, a digital printing layer, a conductive network layer and an OPP heat shrinkage layer which are arranged from bottom to top. According to the fragile label, gradient distribution of the bonding force is achieved, so that when the label is uncovered by external force, the label is prone to being broken in an area with the weak bonding force, an obvious uncovering trace is left, illegal transfer and repeated use of the label are effectively prevented, and the problem that a traditional fragile label is single in bonding force is solved. Compared with a single thermal shrinkage triggering failure mechanism of a traditional fragile paper anti-counterfeit label, the fragile paper anti-counterfeit label is of an electric-thermal-force multi-field coupling synergistic failure mechanism and has multiple anti-counterfeit characteristics, and the anti-counterfeit complexity and the anti-counterfeit difficulty are greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-counterfeiting labels, in particular to an anti-tear and fragile paper anti-counterfeiting label and a manufacturing method thereof. Background Art

[0002] An anti-counterfeiting mark is a mark that can be pasted, printed, or transferred onto the surface of the subject matter, or on the packaging of the subject matter, or on the subject matter's accessories (such as product tags, business cards, and anti-counterfeiting cards), and has an anti-counterfeiting function.

[0003] Currently, many manufacturers use various types of anti-counterfeiting labels to protect their brands. However, in the current era of economic profit, counterfeiting and substandard products are rampant, harming consumer interests and even causing consumers to lose trust in brands. For example, with famous liquor, manufacturers use fragile paper anti-counterfeiting labels on bottle caps and packaging seals, intended to break apart immediately and prevent reuse. However, counterfeiters use hair dryers, which, under the influence of high temperatures, can still slowly peel these labels, defeating the purpose of product anti-counterfeiting.

[0004] Patent CN110827661A discloses a fragile label comprising fragile paper with an adhesive layer coated on the back. The adhesive layer is a composite pressure-sensitive adhesive comprising a heat-shrinkable film and an acrylic pressure-sensitive adhesive coated on the heat-shrinkable film. While this label exhibits a certain degree of tamper resistance, it primarily relies on a single physical mechanism, achieving anti-counterfeiting through the physical fracturing of the fragile paper and the shrinkage of the heat-shrinkable film (such as PET film). This anti-counterfeiting feature is primarily based on the fragility of the material, resulting in a low level of security and potential for improvement. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an anti-tear fragile paper anti-counterfeiting label and a production method thereof, upgrading the traditional fragile paper anti-counterfeiting label to an intelligent response label with multi-dimensional defect coupling. While retaining mature processes such as OPP heat shrinkage and fragile paper substrate, the coupling amplification effect of multi-dimensional defects is used to achieve the unity of deterministic failure and random fragmentation of the anti-counterfeiting label under thermal attack, thereby meeting the requirements of industrial mass production.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] In a first aspect, the present invention provides an anti-tampering fragile paper anti-counterfeiting label, comprising a dynamic adhesive layer, a fragile paper substrate layer, a relief printing layer, a grating defect layer, a stress inducing layer, a digital printing layer, a conductive network layer, and an OPP heat shrink layer arranged from bottom to top;

[0008] The dynamic bonding layer uses DA-TPU composite glue, and the bonding force is distributed in a gradient from the center to the edge; the fragile paper substrate layer uses 45g / m 2cotton pulp paper; the relief printing layer uses acrylic resin ink doped with 8wt% MoS2 nanosheets and 5wt% thermochromic dye; the grating defect layer uses TiO2 nanocolumn arrays; the stress inducing layer uses a lactic acid-glycolic acid copolymer matrix doped with 12wt% ZnO nanoparticles with a particle size of 50nm; the digital printing layer uses acrylic resin ink containing 15wt% CsPbBr3@PLGA quantum dot microcapsules and 8wt% MoS2 nanosheets; the conductive network layer uses a graphene / AgNW hybrid network with ZnO nanorods with a 500nm spacing inserted in a directionally spaced pattern; the OPP heat shrinkable layer uses a biaxially oriented polypropylene film coated with a 15wt% ZnO-doped water-based polyurethane adhesive.

[0009] As a preferred embodiment of the present invention, the preparation method of the DA-TPU composite glue used in the dynamic bonding layer is: furan methyl glycidyl ether and bismaleimide are mixed in a molar ratio of 2:1, dissolved in a DMF / THF solvent, and a TPU matrix is added to make the solid content reach 25%, and a magnetic stirrer is used to stir at room temperature until the solution is uniform and transparent, the stirring speed is 500 rpm, and the time is 2 hours, followed by vacuum degassing to remove bubbles, the degassing time is 30 minutes, and the vacuum degree is -0.09 MPa; wherein, the volume ratio of DMF to THF in the DMF / THF solvent is 3:7; the thickness of the dynamic bonding layer is controlled at 18 μm ± 1 μm.

[0010] As a preferred embodiment of the present invention, the cotton pulp paper used in the fragile paper substrate layer is made of cotton linter pulp, polyethylene oxide and wet strength agent PAE in a mass ratio of 85:10:5, with a surface roughness Ra of 3.2 μm, and the thickness of the fragile paper substrate layer is controlled at 80 μm±2 μm.

[0011] As a preferred embodiment of the present invention, the method for preparing the relief printing layer is as follows: acrylic resin, MoS2 nanosheets, thermochromic dye and ethanol / water mixed solvent are weighed in a mass ratio of 60:8:5:27, the MoS2 nanosheets are added to the ethanol / water mixed solvent for ultrasonic treatment for 30 minutes, and then mixed with the thermochromic dye and acrylic resin and stirred to a viscosity of 3500 cP at 25°C, wherein the ultrasonic power is 500 W, the stirring speed is 800 rpm, the stirring time is 2 hours, the volume ratio of ethanol to water in the ethanol / water mixed solvent is 1:1, and the color development temperature of the thermochromic dye is 65°C; a rotary relief printing press is used for printing, a printing plate with a screen line number of 150 LPI, a printing pressure of 0.8 MPa, a printing speed of 10 m / min, and a printing pressure gradient of 0.8-1.2 MPa to induce microcracks. After printing, the film is immediately dried by hot air at 80°C for 30 seconds and UV cured with a curing wavelength of 365 nm and an energy of 300 mJ / cm 2Fixed pattern; the thickness of the relief printing layer is controlled at 25μm±2μm.

[0012] As a preferred embodiment of the present invention, the grating defect layer fabrication method comprises: cleaning a chrome-plated quartz glass substrate, immersing it in a Piranha solution for 30 minutes, rinsing it with deionized water, and then drying it with nitrogen. The Piranha solution is prepared by mixing concentrated sulfuric acid and hydrogen peroxide in a volume ratio of 3:1. Then, a PMMA photoresist is spin-coated to a thickness of 200 nm at a spin speed of 3000 rpm for 30 seconds, and pre-baking at 180° C. for 2 minutes. Then, an electron beam lithography machine is used for zone exposure, wherein the dose of the 300 nm periodic area is 300 μC / cm 2 , accelerating voltage 100kV, dose 350μC / cm3 in 350nm periodic area 2 , the dose in the 400nm periodic area is 400μC / cm 2 , after 60s of development treatment, a photoresist template was formed; the photoresist template was placed in the ALD reaction chamber, the temperature was set at 150℃, the precursor was introduced, TiCl4 pulse 0.1s, N2 purge 15s, H2O pulse 0.1s, N2 purge 15s, the cycle was repeated 400 times, the deposition thickness was 400nm±5%, and the growth rate was 2.5%. / cycle, and then annealed in a nitrogen environment at 450℃ for 2h, using a 100W parallel plate plasma reactor with a pressure of 50Pa and an Ar / O2 mixed gas with a volume ratio of 4:1 for 3min; the thickness of the grating defect layer was controlled to be 12μm±1μm.

[0013] As a preferred embodiment of the present invention, the stress-inducing layer preparation method is as follows: PLGA (lactic acid-glycolic acid copolymer) and ZnO nanoparticles with a particle size of 50 nm are weighed in a mass ratio of 88:12, mixed and dissolved in a dichloromethane solvent, and stirred until uniform at a stirring speed of 600 rpm for 1 hour to obtain a PLGA matrix; an 800 nm femtosecond laser is used to engrave a microgroove structure with a depth of 2 μm and a spacing of 10 μm on the surface of the PLGA matrix, and the residual stress field is controlled within the range of 0.5-1.2 MPa; and the thickness of the stress-inducing layer is controlled to be 20 μm±1 μm.

[0014] As a preferred embodiment of the present invention, the digital printing layer is prepared by weighing acrylic resin, MoS2 nanosheets, photoinitiator and CsPbBr3@PLGA quantum dot microcapsules in a ratio of 75:8:2:15, stirring until uniform after mixing, stirring at a speed of 800 rpm, time for 2 hours, and performing vacuum degassing to remove bubbles, the degassing time is 30 minutes, and the vacuum degree is -0.09 MPa; using a UV inkjet printer to print according to the designed pattern, the printing pressure is 0.6 MPa, the printing speed is 8 m / min, and UV curing is immediately performed after printing, the curing wavelength is 365 nm, and the energy is 500 mJ / cm 2 ;The thickness of the digital printing layer is controlled at 15μm±1μm.

[0015] As a preferred embodiment of the present invention, the conductive network layer is prepared by preparing an ethanol solution containing 0.1MAgNO3 and 12wt% PVP, magnetically stirring for 12h until uniform, stirring at a speed of 500rpm, injecting it into an electrospinning machine, setting the voltage to 15kV, the receiving distance to 15cm, and the ambient humidity to less than 30%RH for electrospinning, and the spinning time is 30min to obtain a surface density of 0.8mg / cm 2 AgNW network, graphene was grown on copper foil in a CVD furnace, the CH4 / H2 gas ratio was controlled to be 1:10, the reaction pressure was 50mTorr, the growth temperature was 1050℃, and the growth time was 30min; PMMA was used to assist wet graphene transfer to the AgNW network surface; an electroplating solution of 0.02M Zn(NO3)2 and 0.02M HMTA was prepared, the electric field strength was set to 50V / cm for electrophoretic deposition, the deposition time was 30s, so that ZnO nanorods grew on the graphene surface along the electric field direction with a spacing of 500nm. After deposition, the conductive network layer was annealed at 350℃ for 1h, and the thickness of the conductive network layer was controlled at 8μm±1μm.

[0016] As a preferred embodiment of the present invention, the OPP heat shrinkable layer is prepared by: taking a biaxially oriented polypropylene base film with an initial thickness of 50 μm, corona treating it at a power of 8 kW and a frequency of 20 kHz, and a treatment speed of 20 m / min to increase the surface tension to ≥38 mN / m, and immediately eliminating static electricity with an ion blower at a wind speed of 3 m / s after the treatment is completed, weighing water-based polyurethane, nano ZnO with a particle size of 50 nm, and wetting agent TEGO Wet 270 in a mass ratio of 82:15:3, placing them in a high-speed disperser and stirring them at 1200 rpm for 30 minutes until uniform, and using a 400-mesh anilox roller coater for coating, setting the glue transfer amount to 6 cm 3 / m 2After passing through the coating head, the base film enters a three-stage drying oven for drying. The first section is 65°C hot air for 30s, the second section is 75°C hot air for 20s, and the third section is 60°C hot air for 10s. The final coating thickness is controlled within the range of 30μm±2μm.

[0017] In a second aspect, the present invention provides a method for manufacturing the aforementioned tamper-resistant and brittle paper anti-counterfeiting label, the specific steps of which are as follows:

[0018] S1. Preheat the hot roller of the laminating machine to 65°C, align the fragile paper substrate layer and the relief printing layer, and laminate them at a pressure of 0.4 MPa and a speed of 5 m / min. After lamination, immediately use a cold roller at 18°C to set the shape. The cold roller speed should be synchronized with the lamination speed.

[0019] S2. Preheat the hot rollers of the laminating machine to 70°C, align the relief printing layer with the grating defect layer, and use a CCD alignment system to ensure the alignment accuracy of the grating pattern and the printed pattern is ±5μm. Lamination is carried out at a pressure of 0.45MPa and a speed of 6m / min. After lamination, an online corona treatment is performed at a power of 3kW and a frequency of 18kHz.

[0020] S3: Apply 3 μm thick UV curing glue on the surface of the grating defect layer, and perform UV curing pretreatment. The curing wavelength is 365 nm and the curing energy is 50 mJ / cm 2 Align and laminate the grating defect layer and the stress-inducing layer, preheat the hot roller of the laminating machine to 75°C, and laminate at a pressure of 0.5 MPa and a speed of 7 m / min. After the lamination is completed, dry it with hot air circulation at 80°C for 10 minutes;

[0021] S4. Apply a conductive adhesive with a thickness of 2 μm on the surface of the stress-inducing layer, align the stress-inducing layer with the digital printing layer, and use a roller press to perform secondary lamination with a lamination pressure of 0.6 MPa and a lamination time of 5 seconds. Preheat the hot roller of the laminating machine to 80°C, and laminate at a pressure of 0.55 MPa and a speed of 8 m / min. After lamination, UV curing is performed with a curing wavelength of 365 nm and an energy of 400 mJ / cm 2 After curing, let it stand for 24 hours. After curing, check the Fano resonance peak offset to ensure that it does not exceed ±2nm.

[0022] S5. Apply 2μm thick UV curing glue on the surface of the digital printing layer, and pre-treat with UV curing. The curing wavelength is 365nm and the curing energy is 100mJ / cm 2 Align the conductive network layer with the digital printing layer, ensuring the pattern alignment accuracy of ±10μm, preheat the hot roller of the laminating machine to 85℃, and laminate at a pressure of 0.6MPa and 8m / min. After the lamination is completed, UV curing is performed at a curing wavelength of 365nm and an energy of 300mJ / cm 2, ensuring that the quantum dot distribution density reaches 4×10 4 Pieces / mm 2 ;

[0023] S6. Apply 4 μm thick hot melt adhesive to the surface of the conductive network layer, align and laminate the digital printed layer with the OPP heat shrink layer, preheat the OPP film using an infrared heater at 80°C for 5 seconds, preheat the hot roller of the laminating machine to 90°C, and laminate at a pressure of 0.65 MPa and a speed of 9 m / min. Monitor the square resistance fluctuation in real time, with an allowable deviation of ±5%. After lamination, cool the film with a cold roller at 15°C for 10 seconds, with the cold roller speed synchronized with the lamination speed.

[0024] S7. Use a multi-stage hot press to perform composite processing on the final product. Set the hot pressing temperature to 70°C, 80°C, and 90°C in sequence. Pass the composite film through the three temperature zones for hot pressing. The residence time in each temperature zone is 10s and the hot pressing pressure is 0.5MPa. After the hot pressing composite is completed, use a peel strength tester to check the interlayer bonding strength to ensure that it is not less than 15N / cm.

[0025] S8. Select a 400 lines / inch anilox roller and adjust the cell volume to 6cm 3 / m 2 The anilox roller accuracy was ±0.5μm, the printing pressure was set to 0.3MPa, the printing speed was 5m / min, the printing environment temperature was 25℃±2℃, the humidity was 50%±5%RH, and the DA-TPU composite adhesive was evenly coated on the fragile paper substrate layer after S7 treatment, and the adhesive layer thickness was controlled within the range of 18μm±1μm; the zone gradient UV curing was performed, and 5mW / cm was used in one zone. 2 The UV-LED light source was irradiated for 30 seconds to form a low adhesion area with a target adhesion of 5N / cm. After curing, it was left to stand for 10 minutes. The second area was exposed to 10mW / cm 2 The UV-LED light source is irradiated for 20 seconds to form a transition zone with a target adhesion of 10N / cm. After curing, an online corona treatment is performed with 15mW / cm in the third zone. 2 Irradiate with UV-LED light source for 15 seconds to form a high adhesion area with a target adhesion of 15N / cm;

[0026] S8. After the finished products are cut, they are packed into aluminum foil bags and sealed with nitrogen. The cutting blade temperature is -10°C. The packaged labels are stored in an environment with a temperature of 25°C ± 2°C and a humidity below 30% RH.

[0027] Compared with the prior art, the present invention has the following beneficial technical effects:

[0028] 1. The present invention realizes the gradient distribution of adhesive force (5→15N / cm2) through chemical crosslinking and gradient curing process of DA-TPU composite adhesive. 2 ), so that when the label is peeled off by external force, it is easy to break in the area with weak adhesion, leaving obvious peeling marks, effectively preventing the illegal transfer and reuse of the label, and solving the problem of single adhesion of traditional fragile labels.

[0029] 2. The present invention combines a grating defect layer (TiO2 nanocolumn array) with a stress-inducing layer (ZnO nanoparticles / lactic acid-glycolic acid copolymer), and achieves multiple anti-counterfeiting and mechanical performance improvements through the synergistic effect of optical effects and stress response.

[0030] 3. The present invention adopts the directional insertion of graphene / AgNW hybrid network and ZnO nanorods in the conductive network layer to optimize the conductive performance and mechanical stability, which not only improves the conductivity of the conductive network but also enhances its mechanical strength.

[0031] 3. The present invention realizes the preparation of high-precision anti-counterfeiting patterns through UV inkjet printing and vacuum degassing treatment. This process combines the fluorescent properties of quantum dot microcapsules to improve the identification difficulty and anti-counterfeiting effect of anti-counterfeiting labels.

[0032] 4. The relief printing layer of the present invention is doped with MoS2 nanosheets and thermochromic dyes, which improves the lubricity and temperature responsiveness of the relief printing layer, making the printed pattern clearer and more durable, and having visual effects such as temperature color change.

[0033] 5. Compared to the single thermal shrinkage-triggered failure mechanism of traditional brittle paper security labels, the present invention utilizes a multi-field coupled electro-thermal-mechanical failure mechanism, resulting in a 64% reduction in fragment size. The density of security features has been increased from the traditional single physical fracture to multiple features including physical fractures, microcracks, quantum dots, conductive networks, gratings, chemical fingerprints, and dynamic bonding. This multi-layered security feature significantly enhances the complexity and difficulty of replicability, meeting the GB / T22258 Class A standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a diagram of the failure process of the tag triggered by heat in the present invention. DETAILED DESCRIPTION

[0035] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments.

[0036] Example

[0037] The present embodiment is an anti-tear fragile paper anti-counterfeiting label, comprising a dynamic adhesive layer, a fragile paper substrate layer, a relief printing layer, a grating defect layer, a stress inducing layer, a digital printing layer, a conductive network layer and an OPP heat shrink layer arranged from bottom to top; the dynamic adhesive layer adopts DA-TPU composite glue, and the bonding force is gradiently distributed from the center to the edge; the fragile paper substrate layer adopts 45g / m2 cotton pulp paper with a pH value of 7.2±0.5; the relief printing layer adopts acrylic resin ink doped with 8wt% MoS2 nanosheets and 5wt% thermochromic dye; the grating defect layer is a conductive network layer, and the stress inducing layer is a conductive network layer, and the OPP heat shrinkable ... The layer uses TiO2 nanocolumn arrays; the stress-inducing layer uses a lactic acid-glycolic acid copolymer matrix, doped with 12wt% of ZnO nanoparticles with a particle size of 50nm; the digital printing layer uses acrylic resin ink containing 15wt% CsPbBr3@PLGA quantum dot microcapsules and 8wt% MoS2 nanosheets; the conductive network layer uses a graphene / AgNW hybrid network, with ZnO nanorods with a directionally inserted spacing of 500nm; the OPP heat shrinkable layer uses a biaxially oriented polypropylene film coated with 15wt% ZnO-doped water-based polyurethane adhesive.

[0038] Specifically, the DA-TPU composite adhesive used in the dynamic bonding layer is prepared by mixing furanyl glycidyl ether and bismaleimide in a molar ratio of 2:1, dissolving the mixture in a DMF / THF solvent, adding the TPU matrix Estane 58887 to a solid content of 25%, and stirring the mixture at room temperature with a magnetic stirrer at a speed of 500 rpm for 2 hours until the solution becomes uniform and transparent. The mixture is then vacuum degassed for 30 minutes at a vacuum degree of -0.09 MPa to remove bubbles. The volume ratio of DMF to THF in the DMF / THF solvent is 3:7. The thickness of the dynamic bonding layer is controlled at 18 μm ± 1 μm.

[0039] Specifically, the cotton pulp paper used in the fragile paper substrate layer is made of cotton linter pulp, polyethylene oxide and wet strength agent PAE in a mass ratio of 85:10:5, with a surface roughness Ra of 3.2 μm, and the thickness of the fragile paper substrate layer is controlled at 80 μm±2 μm.

[0040] In this embodiment, the moisture content of the cotton pulp paper is controlled at 6.5±0.5%.

[0041] Specifically, the method for preparing the relief printing layer is as follows: acrylic resin, MoS2 nanosheets, thermochromic dye and ethanol / water mixed solvent are weighed in a mass ratio of 60:8:5:27, the MoS2 nanosheets are added to the ethanol / water mixed solvent for ultrasonic treatment for 30 minutes, and then mixed with the thermochromic dye and acrylic resin and stirred to a viscosity of 3500 cP at 25°C, wherein the ultrasonic power is 500W, the stirring speed is 800rpm, the stirring time is 2h, the volume ratio of ethanol to water in the ethanol / water mixed solvent is 1:1, and the color development temperature of the thermochromic dye is 65°C; a rotary relief printing press is used for printing, a printing plate with a screen line number of 150LPI, a printing pressure of 0.8MPa, a printing speed of 10m / min, and a printing pressure gradient is adjusted to 0.8-1.2MPa to induce microcracks. After printing, the film is immediately dried by 80°C hot air for 30s and UV cured with a curing wavelength of 365nm and an energy of 300mJ / cm 2 Fixed pattern; the thickness of the relief printing layer is controlled at 25μm±2μm.

[0042] Specifically, the grating defect layer fabrication method comprises the following steps: cleaning a chrome-plated quartz glass substrate, immersing it in a Piranha solution for 30 minutes, rinsing it with deionized water, and then drying it with nitrogen. The Piranha solution is prepared by mixing concentrated sulfuric acid and hydrogen peroxide in a volume ratio of 3:1. Then, PMMA photoresist AR-P 679.04 is spin-coated to a thickness of 200 nm at a spin speed of 3000 rpm for 30 seconds, and pre-baking at 180°C for 2 minutes. Partition exposure is performed using an electron beam lithography machine (JEOL JBX-6300FS), wherein the dose of the 300 nm period area is 300 μC / cm 2 , accelerating voltage 100kV, dose 350μC / cm3 in 350nm periodic area 2 , the dose in the 400nm periodic area is 400μC / cm 2 , after 60s of development treatment, a photoresist template was formed; the photoresist template was placed in the ALD reaction chamber, the temperature was set at 150℃, the precursor was introduced, TiCl4 pulse 0.1s, N2 purge 15s, H2O pulse 0.1s, N2 purge 15s, the cycle was repeated 400 times, the deposition thickness was 400nm±5%, and the growth rate was 2.5%. / cycle, and then annealed in a nitrogen environment at 450℃ for 2h, using a 100W parallel plate plasma reactor with a pressure of 50Pa and an Ar / O2 mixed gas with a volume ratio of 4:1 for 3min; the thickness of the grating defect layer was controlled to be 12μm±1μm.

[0043] Specifically, the stress-inducing layer preparation method comprises: weighing PLGA (lactic acid-glycolic acid copolymer) and ZnO nanoparticles with a particle size of 50 nm in a mass ratio of 88:12, dissolving the mixture in a dichloromethane solvent, and stirring until uniform at a stirring speed of 600 rpm for 1 hour to obtain a PLGA matrix; using an 800 nm femtosecond laser to engrave a microgroove structure with a depth of 2 μm and a spacing of 10 μm on the surface of the PLGA matrix, controlling the residual stress field within the range of 0.5-1.2 MPa; and controlling the thickness of the stress-inducing layer to be 20 μm±1 μm.

[0044] Specifically, the digital printing layer preparation method is as follows: acrylic resin, MoS2 nanosheets, photoinitiator and CsPbBr3@PLGA quantum dot microcapsules are weighed in a ratio of 75:8:2:15, stirred until uniform after mixing, with a stirring speed of 800 rpm for 2 hours, and vacuum degassing treatment is performed to remove bubbles, with a degassing time of 30 minutes and a vacuum degree of -0.09 MPa; a UV inkjet printer is used to print according to the designed pattern, with a printing pressure of 0.6 MPa and a printing speed of 8 m / min, and UV curing is immediately performed after printing is completed, with a curing wavelength of 365 nm and an energy of 500 mJ / cm 2 ;The thickness of the digital printing layer is controlled at 15μm±1μm.

[0045] Specifically, the conductive network layer is prepared by preparing an ethanol solution containing 0.1MAgNO3 and 12wt% PVP, magnetically stirring for 12 hours until uniform, at a stirring speed of 500rpm, injecting it into an electrospinning machine, setting the voltage to 15kV, the receiving distance to 15cm, and the ambient humidity to less than 30%RH for electrospinning, and the spinning time to 30min to obtain a surface density of 0.8mg / cm 2 AgNW network, graphene was grown on copper foil in a CVD furnace, the CH4 / H2 gas ratio was controlled to be 1:10, the reaction pressure was 50mTorr, the growth temperature was 1050℃, and the growth time was 30min; PMMA was used to assist wet graphene transfer to the AgNW network surface; an electroplating solution of 0.02MZn(NO3)2 and 0.02M HMTA was prepared, the electric field strength was set to 50V / cm for electrophoretic deposition, the deposition time was 30s, and ZnO nanorods were grown on the graphene surface along the electric field direction with a spacing of 500nm. After deposition, the conductive network layer was annealed at 350℃ for 1h, and the thickness of the conductive network layer was controlled at 8μm±1μm.

[0046] In this embodiment, the sheet resistance gradient of the conductive network layer is 50-200Ω / □.

[0047] Specifically, the OPP heat shrinkable layer is prepared by: taking a biaxially oriented polypropylene base film, corona treating it at a power of 8kW and a frequency of 20kHz, and a treatment speed of 20m / min to increase the surface tension to ≥38mN / m; immediately after the treatment, using an ion blower to eliminate static electricity at a wind speed of 3m / s; weighing waterborne polyurethane, nano ZnO with a particle size of 50nm, and wetting agent TEGO Wet 270 in a mass ratio of 82:15:3; placing them in a high-speed disperser and stirring them at 1200rpm for 30min until uniform; using a 400-mesh anilox roller coater for coating, and setting the glue transfer amount to 6cm 3 / m 2 After passing through the coating head, the base film enters a three-stage drying oven for drying. The first section is 65°C hot air for 30s, the second section is 75°C hot air for 20s, and the third section is 60°C hot air for 10s. The final coating thickness is controlled within the range of 30μm±2μm.

[0048] In this embodiment, the biaxially oriented polypropylene base film used has an initial thickness of 50 μm and a heat shrinkage rate of MD 60% / CD 40% @ 90°C.

[0049] The manufacturing method of the anti-tear and fragile paper anti-counterfeiting label of this embodiment has the following specific steps:

[0050] S1. Preheat the hot roller of the laminating machine to 65°C, align the fragile paper substrate layer and the relief printing layer, and laminate them at a pressure of 0.4 MPa and a speed of 5 m / min. After lamination, immediately use a cold roller at 18°C to set the shape. The cold roller speed should be synchronized with the lamination speed.

[0051] S2. Preheat the hot rollers of the laminating machine to 70°C, align the relief printing layer with the grating defect layer, and use a CCD alignment system to ensure the alignment accuracy of the grating pattern and the printed pattern is ±5μm. Lamination is carried out at a pressure of 0.45MPa and a speed of 6m / min. After lamination, an online corona treatment is performed at a power of 3kW and a frequency of 18kHz.

[0052] S3: Apply 3 μm thick UV curing glue on the surface of the grating defect layer, and perform UV curing pretreatment. The curing wavelength is 365 nm and the curing energy is 50 mJ / cm 2 Align and laminate the grating defect layer and the stress-inducing layer, preheat the hot roller of the laminating machine to 75°C, and laminate at a pressure of 0.5 MPa and a speed of 7 m / min. After the lamination is completed, dry it with hot air circulation at 80°C for 10 minutes;

[0053] S4. Apply a conductive adhesive with a thickness of 2 μm on the surface of the stress-inducing layer, align the stress-inducing layer with the digital printing layer, and use a roller press to perform secondary lamination with a lamination pressure of 0.6 MPa and a lamination time of 5 seconds. Preheat the hot roller of the laminating machine to 80°C, and laminate at a pressure of 0.55 MPa and a speed of 8 m / min. After lamination, UV curing is performed with a curing wavelength of 365 nm and an energy of 400 mJ / cm 2 After curing, let it stand for 24 hours. After curing, check the Fano resonance peak offset to ensure that it does not exceed ±2nm.

[0054] S5. Apply 2μm thick UV curing glue on the surface of the digital printing layer, and pre-treat with UV curing. The curing wavelength is 365nm and the curing energy is 100mJ / cm 2 Align the conductive network layer with the digital printing layer, ensuring the pattern alignment accuracy of ±10μm, preheat the hot roller of the laminating machine to 85℃, and laminate at a pressure of 0.6MPa and 8m / min. After the lamination is completed, UV curing is performed at a curing wavelength of 365nm and an energy of 300mJ / cm 2 , ensuring that the quantum dot distribution density reaches 4×10 4 Pieces / mm 2 ;

[0055] S6. Apply 4 μm thick hot melt adhesive to the surface of the conductive network layer, align and laminate the digital printed layer with the OPP heat shrink layer, preheat the OPP film using an infrared heater at 80°C for 5 seconds, preheat the hot roller of the laminating machine to 90°C, and laminate at a pressure of 0.65 MPa and a speed of 9 m / min. Monitor the square resistance fluctuation in real time, with an allowable deviation of ±5%. After lamination, cool the film with a cold roller at 15°C for 10 seconds, with the cold roller speed synchronized with the lamination speed.

[0056] S7. Use a multi-stage hot press to perform composite processing on the final product. Set the hot pressing temperature to 70°C, 80°C, and 90°C in sequence. Pass the composite film through the three temperature zones for hot pressing. The residence time in each temperature zone is 10s and the hot pressing pressure is 0.5MPa. After the hot pressing composite is completed, use a peel strength tester to check the interlayer bonding strength to ensure that it is not less than 15N / cm.

[0057] S8. Select a 400 lines / inch anilox roller and adjust the cell volume to 6cm 3 / m 2 The anilox roller accuracy was ±0.5μm, the printing pressure was set to 0.3MPa, the printing speed was 5m / min, the printing environment temperature was 25℃±2℃, the humidity was 50%±5%RH, and the DA-TPU composite adhesive was evenly coated on the fragile paper substrate layer after S7 treatment, and the adhesive layer thickness was controlled within the range of 18μm±1μm; the zone gradient UV curing was performed, and 5mW / cm was used in one zone. 2The UV-LED light source was irradiated for 30 seconds to form a low adhesion area with a target adhesion of 5N / cm. After curing, it was left to stand for 10 minutes. The second area was exposed to 10mW / cm 2 The UV-LED light source is irradiated for 20 seconds to form a transition zone with a target adhesion of 10N / cm. After curing, an online corona treatment is performed with 15mW / cm in the third zone. 2 Irradiate with UV-LED light source for 15 seconds to form a high adhesion area with a target adhesion of 15N / cm;

[0058] S8. After the finished products are cut, they are packed into aluminum foil bags and sealed with nitrogen. The cutting blade temperature is -10°C. The packaged labels are stored in an environment with a temperature of 25°C ± 2°C and a humidity below 30% RH.

[0059] In this embodiment, when the conductive network layer is composited with the digital printing layer, the quantum dot damage rate is controlled to be less than 1%.

[0060] In this embodiment, after the final product is composited using a multi-stage hot press, the interlayer peeling strength is ≥15N / cm.

[0061] In this embodiment, before the finished product is cut, online detection is performed. The fluorescence intensity detection is performed by integrating a 405nm laser probe, detecting 5 points per meter, and requiring a quantum dot distribution density of 5×10 4 Pieces / mm 2 Conductive uniformity testing is performed by randomly inspecting 10 locations on each roll using a four-probe resistance meter. The square resistance gradient must conform to a five-step distribution of 50→200Ω / □.

[0062] The label of this embodiment has a shelf life of 12 months and must be used within 48 hours after opening.

[0063] Comparative Example

[0064] A commercially available brittle paper anti-counterfeiting label includes an adhesive layer, a brittle paper layer, a printing layer, and a heat shrinkable film OPP from bottom to top, which are laminated by hot pressing; the brittle paper layer is made of cotton pulp paper with a thickness of 80μm; the printing layer is made of acrylic resin ink with a thickness of 25μm, and the heat shrinkable film OPP is made of biaxially oriented polypropylene film with a thickness of 30μm; the adhesive layer is 20μm thick and uses Tesa's acrylic ester pressure-sensitive adhesive 6940.

[0065] Test Example 1 Hair dryer damage test

[0066] (1) Test equipment:

[0067] Hair dryer, Philips HP8232 (2000W, wind speed 15m / s)

[0068] Thermometer: FLIR T540 (accuracy ±1°C)

[0069] High-speed camera: Phantom VEO 410 (1000 fps)

[0070] (2) Testing process

[0071] The label of the embodiment was attached to 80g / m2 neutral paper, cured at room temperature for 24 hours, and continuously heated with a hair dryer at a vertical distance of 5 cm. The temperature field distribution was recorded by an infrared thermal imager, and the fragmentation process was captured by a high-speed camera.

[0072] (3) Judgment criteria

[0073] Fragmentation time ≤ 8s;

[0074] Maximum fragment area <0.25mm 2 ;

[0075] Fluorescence intensity residual ≤10%;

[0076] (4) Test results

[0077] As shown in Table 1.

[0078] Table 1 Hair dryer damage test results

[0079] Test items Test conditions result Compliance Thermal response time 2000W hair dryer 5.2±0.3s@60℃ Better than standard (≤8s) Fragment size distribution High-speed imaging analysis <![CDATA[0.18±0.03mm 2 ]]> 100% compliance Fluorescence quenching rate Fluorescence spectrometer detection <![CDATA[I / I0=0.07±0.01]]> Better than standard (≤0.1)

[0080] Test Example 2 Thermal Response Test

[0081] The quantum dot extinction rate, conductivity jump rate, crack density and adhesion failure time of the label of the embodiment were tested under hot air at 65° C. and 80° C., respectively. The test results are shown in Table 2.

[0082] Table 2 Thermal response test results

[0083]

[0084]

[0085] Test Example 3: Anti-environmental interference performance test

[0086] Under different aging conditions, the labels of the examples were tested for their environmental interference resistance, including quantum dot QY retention, conductive stability, and adhesion strength attenuation. The test results are shown in Table 3.

[0087] Table 3 Results of anti-environmental interference performance

[0088]

[0089] Test Example 4 Performance Comparison Test

[0090] The labels of the embodiment and comparative example were used to perform performance tests on non-transferability, thermal response time (60° C.), fragment size, environmental stability, and production cost. The results are shown in Table 4.

[0091] Table 4 Performance comparison test results

[0092] index Comparative Example Example Non-transferability rate 92％ 99％ Thermal response time (60℃) 12s 5.2s Fragment size <![CDATA[0.5-1mm 2 ]]> <![CDATA[0.18±0.03mm 2 ]]> Environmental stability Failure after 500h at 85℃ / 85%RH Fluorescence retention rate 83% production costs ￥0.15 / piece ￥0.18 / piece

[0093] Based on the above test results, it can be seen that the non-transferability rate of the label of the present invention is significantly increased, and the risk of the label being completely transferred is basically eliminated. The anti-counterfeiting complexity and recognition reliability are significantly enhanced, and the thermal response time (60°C environment) is shortened to 5.2s, so that the thermosensitive anti-counterfeiting features can be displayed faster, improving the efficiency of instant verification, reducing the size of fragments, and greatly increasing the technical difficulty of destroying the integrity of the label.

[0094] The thermal trigger failure process of the label of the present invention is as follows Figure 1 As shown, when directional heating is applied using a heat source such as a hair dryer, the heat first penetrates the label's surface, creating a temperature gradient within the material. The biaxially oriented polypropylene (OPP) film shrinks dramatically above a critical temperature of 60°C, reaching a shrinkage rate of 60%. This sudden volume change produces two destructive effects: mechanical stretching causes the embedded conductive network to break, triggering a sudden resistance change (ΔR > 500%), directly destroying the electrical anti-counterfeiting feature; and contraction stress is transmitted to the interface of the underlying material, weakening the interlayer bonding. PLGA stress release and deformation: The polylactic-co-glycolic acid (PLGA) substrate undergoes a glass transition under heating, with a sharp drop in modulus. The softened PLGA undergoes two responses: releasing residual stress accumulated during processing, eliminating the internal prestress equilibrium of the material, and generating a fluid dynamic response through a viscoelastic transition, accelerating the deformation transmission caused by the shrinkage of the upper OPP film. Microcapsules encapsulating quantum dots rupture due to the following mechanisms: softening of the PLGA, which reduces the mechanical strength of the capsule wall; shrinkage of the OPP film, which generates interfacial shear stress; and internal pressure generated by the thermal expansion of the phase change material within the capsule. Following rupture, quantum dot leakage triggers fluorescence quenching, while the released fluorescent material forms a visible stain mark. Cascading failure mechanism: These changes form a positive feedback loop: conductive network rupture → increased Joule heating → accelerated softening of the PLGA; shrinkage of the OPP film → interfacial delamination → increased exposed area of the quantum dot capsule; fluorescence quenching → disappearance of the optical detection signal → triggering anti-counterfeiting failure determination. Final physical destruction: Ultimately, under the coupled effects of thermo-mechanical-chemical forces, the label substrate catastrophically shatters, with the edges of the fragments exhibiting typical brittle fracture characteristics, eliminating the possibility of human tearing and causing simultaneous failure of all functional layers, making repair impossible. This failure mechanism, through the spatiotemporal synchronization of multiple physical changes, achieves an irreversible process from thermal stimulus input to complete functional loss, making it particularly suitable for high-security anti-counterfeiting scenarios requiring single-use verification.

[0095] The above is merely an embodiment of the present invention, and its description is relatively specific and detailed, but it should not be understood as limiting the scope of the present invention. It should be pointed out that those skilled in the art can make a number of modifications and improvements without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention.

Claims

1. A tamper-resistant and fragile paper anti-counterfeiting label, characterized by: It includes a dynamic adhesive layer, a fragile paper substrate layer, a relief printing layer, a grating defect layer, a stress inducing layer, a digital printing layer, a conductive network layer and an OPP heat shrink layer arranged from bottom to top; The dynamic adhesive layer uses DA-TPU composite adhesive, and the adhesive force is gradiently distributed from the center to the edge; the fragile paper substrate layer uses 45g / m2 cotton pulp paper with a pH value of 7.2±0.5; the relief printing layer uses acrylic resin ink doped with 8wt% MoS2 nanosheets and 5wt% thermochromic dye; the grating defect layer uses TiO2 nanopillar arrays; the stress inducing layer uses a lactic acid-glycolic acid copolymer matrix doped with 12wt% ZnO nanoparticles with a particle size of 50nm; the digital printing layer uses acrylic resin ink containing 15wt% CsPbBr3@PLGA quantum dot microcapsules and 8wt% MoS2 nanosheets; the conductive network layer uses a graphene / AgN W hybrid network with directionally inserted ZnO nanorods with a spacing of 500nm; and the OPP heat shrinkable layer uses a biaxially oriented polypropylene film coated with 15wt% ZnO-doped water-based polyurethane adhesive.

2. The anti-tamper resistant and fragile paper anti-counterfeiting label according to claim 1, characterized in that: The DA-TPU composite adhesive used in the dynamic adhesive layer is prepared by mixing furanyl glycidyl ether and bismaleimide in a molar ratio of 2:1, dissolving the mixture in a DMF / THF solvent, adding a TPU matrix to a solid content of 25%, stirring the mixture with a magnetic stirrer at room temperature at a speed of 500 rpm for 2 hours until the solution is uniform and transparent, followed by vacuum degassing for 30 minutes at a vacuum degree of -0.09 MPa to remove bubbles. The volume ratio of DMF to THF in the DMF / THF solvent is 3:7, and the thickness of the dynamic adhesive layer is controlled to be 18 μm±1 μm.

3. The anti-tamper resistant and fragile paper anti-counterfeiting label according to claim 1, characterized in that: The cotton pulp paper used in the fragile paper substrate layer is made of cotton linter pulp, polyethylene oxide and wet strength agent PAE in a mass ratio of 85:10:5, with a surface roughness Ra of 3.2 μm. The thickness of the fragile paper substrate layer is controlled at 80 μm±2 μm.

4. The anti-tear fragile paper anti-counterfeiting label according to claim 1, characterized in that: The method for preparing the relief printing layer comprises the following steps: weighing acrylic resin, MoS2 nanosheets, thermochromic dye and ethanol / water mixed solvent in a mass ratio of 60:8:5:27, adding the MoS2 nanosheets to the ethanol / water mixed solvent for ultrasonic treatment for 30 minutes, mixing and stirring with the thermochromic dye and acrylic resin until the viscosity reaches 3500 cP at 25°C, wherein the ultrasonic power is 500 W, the stirring speed is 800 rpm, the stirring time is 2 hours, the volume ratio of ethanol to water in the ethanol / water mixed solvent is 1:1, and the color development temperature of the thermochromic dye is 65°C; using a rotary relief printing press for printing, adopting a printing plate with a screen line number of 150 LPI, a printing pressure of 0.8 MPa, a printing speed of 10 m / min, adjusting the printing pressure gradient to 0.8-1.2 MPa to induce microcracks, and immediately drying by hot air drying at 80°C for 30 seconds and UV curing after printing, with a curing wavelength of 365 nm and an energy of 300 mJ / cm 2 Fixed pattern; the thickness of the relief printing layer is controlled at 25μm±2μm.

5. The anti-tamper resistant and fragile paper anti-counterfeiting label according to claim 1, characterized in that: The grating defect layer fabrication method comprises the following steps: cleaning a chrome-plated quartz glass substrate, immersing the substrate in a Piranha solution for 30 minutes, rinsing with deionized water, and then drying with nitrogen, wherein the Piranha solution is prepared by mixing concentrated sulfuric acid and hydrogen peroxide in a volume ratio of 3:1; spin-coating a PMMA photoresist to a thickness of 200 nm at a spin-coating speed of 3000 rpm for 30 seconds, and pre-baking at 180° C. for 2 minutes; and performing zone exposure using an electron beam lithography machine, wherein the dose of a 300 nm periodic area is 300 μC / cm 2 , accelerating voltage 100kV, dose 350μC / cm3 in 350nm periodic area 2 , the dose in the 400nm periodic area is 400μC / cm 2 , after 60s of development treatment, a photoresist template was formed; the photoresist template was placed in the ALD reaction chamber, the temperature was set at 150℃, the precursor was introduced, TiCl4 pulse 0.1s, N2 purge 15s, H2O pulse 0.1s, N2 purge 15s, the cycle was repeated 400 times, the deposition thickness was 400nm±5%, and the growth rate was 2.5%. Then, the grating was annealed in a nitrogen environment at 450°C for 2 hours. A 100W parallel plate plasma reactor was used, the pressure was controlled at 50Pa, and an Ar / O2 mixed gas with a volume ratio of 4:1 was introduced for 3 minutes. The thickness of the grating defect layer was controlled at 12μm±1μm.

6. The anti-tamper resistant and fragile paper anti-counterfeiting label according to claim 1, characterized in that: The stress-inducing layer preparation method comprises the following steps: weighing PLGA and ZnO nanoparticles with a particle size of 50 nm in a mass ratio of 88:12, mixing and dissolving the mixture in a dichloromethane solvent, and stirring the mixture until uniform at a stirring speed of 600 rpm for 1 hour to obtain a PLGA matrix; using an 800 nm femtosecond laser to engrave a microgroove structure with a depth of 2 μm and a spacing of 10 μm on the surface of the PLGA matrix, and controlling the residual stress field within a range of 0.5-1.2 MPa; and controlling the thickness of the stress-inducing layer to be 20 μm±1 μm.

7. The anti-tamper resistant and fragile paper anti-counterfeiting label according to claim 1, characterized in that: The digital printing layer is prepared by weighing acrylic resin, MoS2 nanosheets, photoinitiator and CsPbBr3@PLGA quantum dot microcapsules in a ratio of 75:8:2:15, stirring until uniform, stirring at a speed of 800 rpm for 2 hours, and performing vacuum degassing to remove bubbles, the degassing time is 30 minutes, and the vacuum degree is -0.09 MPa; Use UV inkjet printer to print according to the design pattern, with a printing pressure of 0.6MPa and a printing speed of 8m / min. After printing, UV curing is immediately carried out with a curing wavelength of 365nm and an energy of 500mJ / cm 2 ;The thickness of the digital printing layer is controlled at 15μm±1μm.

8. The anti-tamper resistant and fragile paper anti-counterfeiting label according to claim 1, characterized in that: The conductive network layer is prepared by preparing an ethanol solution containing 0.1M AgNO3 and 12wt% PVP, magnetically stirring the solution for 12 hours until uniform, at a stirring speed of 500 rpm, injecting the solution into an electrospinning machine, setting the voltage to 15 kV, the receiving distance to 15 cm, and the ambient humidity to less than 30% RH for electrospinning for 30 minutes to obtain a surface density of 0.8 mg / cm 2 AgNW network, graphene was grown on copper foil in a CVD furnace, the CH4 / H2 gas ratio was controlled to be 1:10, the reaction pressure was 50mTorr, the growth temperature was 1050℃, and the growth time was 30min; PMMA was used to assist wet graphene transfer to the AgNW network surface; an electroplating solution of 0.02MZn(NO3)2 and 0.02MHMTA was prepared, the electric field strength was set to 50V / cm for electrophoretic deposition, the deposition time was 30s, and ZnO nanorods were grown on the graphene surface along the electric field direction with a spacing of 500nm. After deposition, the conductive network layer was annealed at 350℃ for 1h, and the thickness of the conductive network layer was controlled at 8μm±1μm.

9. The anti-tamper resistant and fragile paper anti-counterfeiting label according to claim 1, characterized in that: The OPP heat shrinkable layer is prepared by: taking a biaxially oriented polypropylene base film with an initial thickness of 50 μm, corona treating it at a power of 8 kW and a frequency of 20 kHz at a treatment speed of 20 m / min to increase the surface tension to ≥38 mN / m; immediately eliminating static electricity with an ion blower at a wind speed of 3 m / s after the treatment; weighing waterborne polyurethane, nano ZnO with a particle size of 50 nm, and wetting agent TEGO Wet270 in a mass ratio of 82:15:3; placing them in a high-speed disperser and stirring them at 1200 rpm for 30 minutes until they are uniform; and coating them with a 400-mesh anilox roller coater, setting the glue transfer amount to 6 cm 3 / m 2 After passing through the coating head, the base film enters a three-stage drying oven for drying. The first section is 65°C hot air for 30s, the second section is 75°C hot air for 20s, and the third section is 60°C hot air for 10s. The final coating thickness is controlled within the range of 30μm±2μm.

10. The method for producing a tamper-resistant and fragile anti-counterfeiting label according to any one of claims 1 to 9, characterized in that: The specific steps are as follows: S1. Preheat the hot roller of the laminating machine to 65°C, align the fragile paper substrate layer and the relief printing layer, and laminate them at a pressure of 0.4 MPa and a speed of 5 m / min. After lamination, immediately use a cold roller at 18°C to set the shape. The cold roller speed should be synchronized with the lamination speed. S2. Preheat the hot rollers of the laminating machine to 70°C, align the relief printing layer with the grating defect layer, and use a CCD alignment system to ensure the alignment accuracy of the grating pattern and the printed pattern is ±5μm. Lamination is carried out at a pressure of 0.45MPa and a speed of 6m / min. After lamination, an online corona treatment is performed at a power of 3kW and a frequency of 18kHz. S3: Apply 3 μm thick UV curing glue on the surface of the grating defect layer, and perform UV curing pretreatment. The curing wavelength is 365 nm and the curing energy is 50 mJ / cm 2 Align and laminate the grating defect layer and the stress-inducing layer, preheat the hot roller of the laminating machine to 75°C, and laminate at a pressure of 0.5 MPa and a speed of 7 m / min. After the lamination is completed, dry it with hot air circulation at 80°C for 10 minutes; S4. Apply a conductive adhesive with a thickness of 2 μm on the surface of the stress-inducing layer, align the stress-inducing layer with the digital printing layer, and use a roller press to perform secondary lamination with a lamination pressure of 0.6 MPa and a lamination time of 5 seconds. Preheat the hot roller of the laminating machine to 80°C, and laminate at a pressure of 0.55 MPa and a speed of 8 m / min. After lamination, UV curing is performed with a curing wavelength of 365 nm and an energy of 400 mJ / cm 2 After curing, let it stand for 24 hours. After curing, check the Fano resonance peak offset to ensure that it does not exceed ±2nm. S5. Apply 2μm thick UV curing glue on the surface of the digital printing layer, and pre-treat with UV curing. The curing wavelength is 365nm and the curing energy is 100mJ / cm 2 Align the conductive network layer with the digital printing layer, ensuring the pattern alignment accuracy of ±10μm, preheat the hot roller of the laminating machine to 85℃, and laminate at a pressure of 0.6MPa and 8m / min. After the lamination is completed, UV curing is performed at a curing wavelength of 365nm and an energy of 300mJ / cm 2 , ensuring that the quantum dot distribution density reaches 4×10 4 Pieces / mm 2 ; S6. Apply 4 μm thick hot melt adhesive to the surface of the conductive network layer, align and laminate the digital printed layer with the OPP heat shrink layer, preheat the OPP film using an infrared heater at 80°C for 5 seconds, preheat the hot roller of the laminating machine to 90°C, and laminate at a pressure of 0.65 MPa and a speed of 9 m / min. Monitor the square resistance fluctuation in real time, with an allowable deviation of ±5%. After lamination, cool the film with a cold roller at 15°C for 10 seconds, with the cold roller speed synchronized with the lamination speed. S7. Use a multi-stage hot press to perform composite processing on the final product. Set the hot pressing temperature to 70°C, 80°C, and 90°C in sequence. Pass the composite film through the three temperature zones for hot pressing. The residence time in each temperature zone is 10s and the hot pressing pressure is 0.5MPa. After the hot pressing composite is completed, use a peel strength tester to check the interlayer bonding strength to ensure that it is not less than 15N / cm. S8. Select a 400 lines / inch anilox roller and adjust the cell volume to 6cm 3 / m 2 , the anilox roller accuracy is ±0.5μm, the printing pressure is set to 0.3MPa, the printing speed is 5m / min, the printing environment temperature is 25℃±2℃, the humidity is 50%±5%RH, and the DA-TPU composite adhesive is evenly coated on the fragile paper substrate layer after S7 treatment, and the adhesive layer thickness is controlled within the range of 18μm±1μm; Partition gradient UV curing, using 5mW / cm in one zone 2 The UV-LED light source was irradiated for 30 seconds to form a low adhesion area with a target adhesion of 5N / cm. After curing, it was left to stand for 10 minutes. The second area was exposed to 10mW / cm 2 The UV-LED light source is irradiated for 20 seconds to form a transition zone with a target adhesion of 10N / cm. After curing, an online corona treatment is performed with 15mW / cm in the third zone. 2 Irradiate with UV-LED light source for 15 seconds to form a high adhesion area with a target adhesion of 15N / cm; S8. After the finished products are cut, they are packed into aluminum foil bags and sealed with nitrogen. The cutting blade temperature is -10°C. The packaged labels are stored in an environment with a temperature of 25°C ± 2°C and a humidity below 30% RH.

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