Anti-fake kraft paper box and anti-fake processing device

Abstract

The invention provides an anti-counterfeiting kraft paper box and an anti-counterfeiting treatment device, and relates to the technical field of carton production and processing, and the anti-counterfeiting kraft paper box is formed by sequentially compounding a substrate layer, an anti-counterfeiting structure layer and a functional coating; the substrate layer is made of a kraft fiber and nano cellulose composite material; the anti-counterfeiting structure layer is a three-dimensional microstructure array formed by laser engraving; the functional coating comprises magnetic ferroferric oxide particles, temperature change ink, photochromic conductive macromolecules, microencapsulated perfume and amphiphilic graphene quantum dots. Comprising a laser engraving unit, a magnetization treatment unit and a fluorescence detection unit, the diffraction efficiency is remarkably improved, the magnetic particles and the quantum dots form a cross-linked network through chemical bonding, rapid response and remarkable resistivity change are achieved, the anti-transfer rate is extremely high, magnetic signals, fluorescence intensity and resistivity change are encoded through a data acquisition system, and the verification precision is extremely high.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of carton production and processing, in particular to a counterfeit-proof kraft carton and a counterfeit-proof processing device. BACKGROUND

[0002] Kraft cartons, as common packaging materials, are widely used in the fields of logistics, food, electronic products, etc. With the increasing number of counterfeit and inferior products in the market circulation, the traditional carton anti-counterfeiting function has been difficult to meet the current high standard anti-counterfeiting demand. Existing anti-counterfeiting technologies mostly use single means, such as two-dimensional codes, holographic labels or temperature-changing inks, etc., which have anti-counterfeiting function to some extent, but generally have problems such as easy copying, poor durability of anti-counterfeiting features, complex verification process or the need for special equipment, etc.

[0003] For example, some anti-counterfeiting cartons achieve anti-counterfeiting by printing special inks on the surface or adding magnetic materials, but such technologies usually rely on external triggering conditions (such as specific light or temperature), and the anti-counterfeiting features are easy to fail due to wear or environmental factors. In addition, some technologies use microstructure optical anti-counterfeiting (such as diffraction gratings), but their preparation process is complex, the cost is high, and they are difficult to be well combined with the carton substrate, resulting in unstable anti-counterfeiting effect.

[0004] In addition, existing anti-counterfeiting technologies lack multi-modal collaborative verification mechanism and cannot provide multiple signal responses such as magnetic, optical, thermal and electrical at the same time, resulting in insufficient reliability and uniqueness of anti-counterfeiting verification. The compatibility and dispersion stability between components in the functional coating are also technical difficulties, which can easily lead to the attenuation of anti-counterfeiting performance due to agglomeration or sedimentation. SUMMARY

[0005] In view of the deficiencies of the prior art, the present application provides a counterfeit-proof kraft carton and a counterfeit-proof processing device, aiming to solve the problems of single traditional anti-counterfeiting means, easy copying and poor durability of anti-counterfeiting features.

[0006] To achieve the above purpose, the present application realizes the following technical scheme:

[0007] A counterfeit-proof kraft carton,

[0008] composed of a base layer, an anti-counterfeiting structure layer and a functional coating in sequence;

[0009] The base layer is made of kraft paper fiber and nanocellulose composite material, and the thickness is 1.0-1.8mm;

[0010] The anti-counterfeiting structure layer is a three-dimensional microstructure array formed by laser engraving, the array spacing is 0.2-0.6mm, and the depth is 0.05-0.25mm;

[0011] The functional coating comprises magnetic iron oxide microparticles, thermochromic ink, photochromic conductive polymer, microencapsulated fragrance, and amphiphilic graphene quantum dots; the amphiphilic graphene quantum dots have a particle size of 2-6 nm and are modified with carboxyl and amino groups on their surface.

[0012] In a preferred embodiment, the magnetic iron oxide microparticles have a particle size of 0.3-3 μm.

[0013] In a preferred embodiment, the mass percentage of each component in the functional coating is as follows: 10%-15% magnetic iron oxide, 20%-30% thermochromic ink, 15%-20% photochromic conductive polymer, 5%-10% microencapsulated fragrance, 3%-8% amphiphilic graphene quantum dots, 0.5%-3% sodium polyacrylate dispersant, and the balance being waterborne polyurethane resin.

[0014] In the preferred embodiment, the photochromic conductive polymer is a poly(3-hexylthiophene) / [6,6]-phenyl-C61-butyrate methyl ester complex.

[0015] In a preferred embodiment, the microencapsulated flavoring is menthol.

[0016] In a preferred embodiment, the three-dimensional microstructure array of the anti-counterfeiting structural layer is a diffraction grating structure, with a surface coated with photosensitive resin of 0.1 mm thickness, and passing through a wavelength of 365 nm and an energy of 500 mJ / cm². 2 UV curing and shaping.

[0017] In a preferred embodiment, the mass ratio of kraft paper fiber to nanocellulose in the base layer is 80:20, the diameter of the nanocellulose is 50-100nm, and the base layer is prepared by a wet molding process with a drying temperature of 80℃ and a pressure of 0.3MPa.

[0018] The preferred technical solution includes the following steps in the preparation process:

[0019] S1. Preparation of the base layer: Pulp kraft paper fibers to a freeness of 35°SR, add nanocellulose and stir at high speed (1000-1400 rpm, 25-35 min), wet form and dry (75-85℃, 0.2-0.4 MPa);

[0020] S2. Preparation of the anti-counterfeiting structural layer: A photosensitive resin (thickness 0.08-0.12mm) is coated on the surface of the base layer. A three-dimensional microstructure array is engraved using an ultraviolet laser with a wavelength of 350-360nm and a pulse frequency of 180-220kHz, followed by ultraviolet curing (energy 450-550mJ / cm). 2 );

[0021] S3. Preparation of functional coatings:

[0022] S3a. Magnetic iron oxide and thermochromic ink are ball-milled and dispersed (250-350 rpm, 1.5-2.5 h), and amphiphilic graphene quantum dots are added for esterification reaction (90-110℃, 2-4 h). During this process, the carboxyl groups (-COOH) on the surface of graphene quantum dots and the hydroxyl groups (-OH) on the surface of iron oxide mainly undergo esterification reaction, while the amino groups (-NH2) can enhance compatibility through hydrogen bonding, thereby forming a modified layer on the surface of the particles and significantly improving the dispersion stability.

[0023] S3b. Add photochromic conductive polymer and microencapsulated fragrance, ultrasonically disperse (35kHz, 25-35min), and form a composite network by utilizing the π-π stacking effect of amphiphilic graphene quantum dots;

[0024] S3c. Dry after screen printing coating (55-65℃, 12-18min);

[0025] S4. Magnetization treatment: The coated cardboard box is placed in an alternating magnetic field, with the magnetic field direction changing 10-20° per second, which promotes the formation of a cross-linked structure between magnetic iron oxide and amphiphilic graphene quantum dots.

[0026] An anti-counterfeiting treatment device for kraft paper boxes, characterized in that:

[0027] It includes a laser engraving unit, a magnetization processing unit, and a fluorescence detection unit;

[0028] The laser engraving unit uses an ultraviolet laser with a wavelength of 350-360nm, a pulse frequency of 180-220kHz, and an engraving accuracy of ≤8μm.

[0029] The magnetization unit employs an alternating magnetic field generator with a magnetic field strength of 0.8-1.2T, a frequency of 8-12Hz, and a magnetic field direction transformation frequency ≥4Hz. Through directional magnetization, the magnetic particles exhibit specific magnetic domain orientations, which not only enhances their magnetic response characteristics but also promotes the stabilization of their cross-linked structure with graphene quantum dots, thereby improving the uniqueness and signal strength of the magnetic anti-counterfeiting features.

[0030] The fluorescence detection unit uses an LED light source with a wavelength of 350-380nm and a CMOS sensor to detect the blue fluorescence of amphiphilic graphene quantum dots and the minty odor released by the fragrance.

[0031] In a preferred embodiment, the engraving path of the laser engraving unit is controlled by a computer, and the engraving depth is adjusted by the laser power of 10-30W and the pulse duration of 1-5ms to ensure that the spacing of the three-dimensional microstructure array is 0.3-0.5mm and the depth is 0.1-0.2mm.

[0032] This invention utilizes magnetic iron(III) oxide to generate eddy current heat in an alternating magnetic field, triggering a thermochromic ink color change (temperature threshold 45℃). Simultaneously, the photochromic conductive polymer undergoes a structural transformation (from β phase to α phase) under ultraviolet light, with the resistivity decreasing from 10... 6 Ω·cm decreased to 10 3 Ω·cm; The leuco dye in thermochromic inks releases protons (H) upon heating. + The hydroxyl groups (-S-) on the surface of the magnetic iron oxide undergo an acid-catalyzed reaction with the thioether groups (-S-) in the photochromic polymer, accelerating its structural transformation; the hydroxyl groups (-OH) on the surface of the magnetic iron oxide form hydrogen bonds with the polyurea-formaldehyde shell of the microencapsulated fragrance, enhancing the thermal stability of the microcapsules.

[0033] Amphiphilic graphene quantum dots can be prepared using well-known methods in the field, such as citric acid carbonization, electrochemical methods, or hydrothermal methods. Surface modification can be achieved by introducing precursors containing amino or carboxyl groups (such as ethylenediamine, citric acid, etc.) during the synthesis process. Amphiphilic graphene quantum dots form hydrogen bonds with hydroxyl groups (-OH) on the surface of magnetic iron oxide (Fe3O4) through amino groups (-NH2), enhancing the dispersion stability of the magnetic particles. In an alternating magnetic field, the π electrons of the amphiphilic graphene quantum dots and the eddy current thermal synergy of the magnetic iron oxide enhance the heating efficiency of the functional coating. The fluorescence properties of the amphiphilic graphene quantum dots and the color changes of the thermochromic ink form a light-color dual-mode response, emitting blue fluorescence (wavelength 430-470 nm) under ultraviolet light. Amphiphilic graphene quantum dots, through π-π stacking, combine with the conjugated structure of photochromic polymers (P3HT:PCBM), enhancing charge transport efficiency and reducing resistivity by 1-2 orders of magnitude. The quantum confinement effect of amphiphilic graphene quantum dots enhances the light absorption capacity of photochromic polymers, increasing the structural transition rate by 1.5-3 times under ultraviolet light irradiation. The amino groups (-NH2) of amphiphilic graphene quantum dots undergo a cross-linking reaction with the polyurea-formaldehyde shell of microencapsulated fragrances (pH = 5-6, catalyst: hydrochloric acid), improving the thermal stability of the microcapsules (increasing the rupture temperature by 5-15℃). The fluorescent labeling function of amphiphilic graphene quantum dots can track the distribution of fragrance microcapsules, and the coating uniformity can be verified using fluorescence microscopy.

[0034] A method for verifying authenticity, characterized by comprising the following steps:

[0035] T1. Magnetic verification: Use a permanent magnet to approach the cardboard box and detect the magnetic field distortion (magnetic flux change rate ≥ 0.25T / s) generated by the synergy of magnetic iron oxide and amphiphilic graphene quantum dots;

[0036] T2. Synergistic verification using thermo-optical-chemical methods:

[0037] T2a. When heated to above 35°C, the thermochromic ink changes from colorless to blue, and the fluorescence intensity of the amphiphilic graphene quantum dots increases by 1.5-3 times;

[0038] T2b. Ultraviolet light irradiation triggers a sharp drop in the resistivity of the photochromic conductive polymer (≥0.5 orders of magnitude), while simultaneously releasing a minty odor;

[0039] T3. Destructive verification: If the coating is scraped off, the three-dimensional microstructure array is destroyed, causing the diffraction grating to fail, the fluorescent labeling of the amphiphilic graphene quantum dots to disappear, and the magnetic signal and electrical signal to become mismatched.

[0040] In the aforementioned thermo-optical-chemical synergistic verification, the fluorescence signal of the amphiphilic graphene quantum dots and the electrical signal of the photochromic conductive polymer are correlated in real time through a data acquisition system to form a unique anti-counterfeiting code, with a verification accuracy of over 99.5%.

[0041] This invention provides an anti-counterfeiting kraft paper box and an anti-counterfeiting processing device. It has the following beneficial effects:

[0042] This invention's anti-counterfeiting structural layer utilizes ultraviolet laser engraving of a diffraction grating array, combined with photosensitive resin coating and ultraviolet curing processes, to form an uncopyable optical fingerprint, significantly improving diffraction efficiency. Magnetic microparticles and quantum dots form a cross-linked network through chemical bonding, generating significant magnetic flux changes with signal intensity far exceeding that of single-component materials. Thermal-optical dual-modal triggering: the synergistic effect of thermochromic ink and photochromic polymer achieves rapid response and significant resistivity changes, with a response speed superior to traditional materials. The fluorescent labeling of quantum dots and microencapsulated fragrances form a dual-modal label with extremely high anti-transfer rate. Quantum dots, as the core cross-linking agent, construct a three-dimensional conductive network through multiple intermolecular forces, significantly improving charge transport efficiency while reducing the microcapsule thermal release threshold. Under an alternating magnetic field, the eddy current heat of quantum dots and the magnetothermal coupling of magnetic microparticles achieve rapid heating. The magnetic signal, fluorescence intensity, and resistivity changes are encoded through a data acquisition system to form a unique anti-counterfeiting code with extremely high verification accuracy. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the structure of the present invention;

[0044] Figure 2 This is a schematic diagram of the micro-network structure mechanism of the functional coating of the present invention;

[0045] Figure 3 This is a schematic diagram of the preparation process of the present invention;

[0046] Figure 4 This is a schematic diagram of the anti-counterfeiting processing device system of the present invention;

[0047] In the diagram: 101-Base layer, 102-Anti-counterfeiting structural layer, 103-Functional coating, 201-Laser engraving unit, 202-Magnetization treatment unit, 203-Fluorescence detection unit. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] Example 1

[0050] like Figure 1 and Figure 2 As shown, a type of anti-counterfeiting kraft paper box.

[0051] It is composed of a base layer 101, an anti-counterfeiting structural layer 102, and a functional coating layer 103 in sequence;

[0052] The base layer 101 is made of a composite material of kraft paper fiber and nanocellulose, with a thickness of 1.0 mm;

[0053] The anti-counterfeiting structural layer 102 is a three-dimensional microstructure array formed by laser engraving, with an array spacing of 0.2 mm and a depth of 0.05 mm;

[0054] The functional coating 103 contains magnetic iron oxide microparticles, thermochromic ink, photochromic conductive polymer, microencapsulated fragrance, and amphiphilic graphene quantum dots; the amphiphilic graphene quantum dots have a particle size of 2 nm and are modified with carboxyl and amino groups on their surface.

[0055] The particle size of the magnetic iron oxide microparticles is 0.3 μm.

[0056] The mass percentages of each component in functional coating 103 are as follows: 10% magnetic iron oxide, 20% thermochromic ink, 15% photochromic conductive polymer, 5% microencapsulated fragrance, 3% amphiphilic graphene quantum dots, 0.5% sodium polyacrylate dispersant, and the balance being waterborne polyurethane resin.

[0057] The photochromic conductive polymer is a poly(3-hexylthiophene) / [6,6]-phenyl-C61-butyrate methyl ester complex.

[0058] The microencapsulated flavoring is menthol.

[0059] The three-dimensional microstructure array of the anti-counterfeiting structural layer 102 is a diffraction grating structure, with a surface coated with photosensitive resin of 0.1 mm thickness, and passes through a wavelength of 365 nm and an energy of 500 mJ / cm². 2 UV curing and shaping.

[0060] The mass ratio of kraft paper fiber to nanocellulose in the base layer 101 is 80:20, the diameter of the nanocellulose is 50nm, and the base layer is prepared by a wet molding process with a drying temperature of 80℃ and a pressure of 0.3MPa.

[0061] A process for manufacturing anti-counterfeiting kraft paper boxes includes the following steps:

[0062] S1. Preparation of base layer 101: Pulp kraft paper fibers to a freeness of 35°SR, add nanocellulose and stir at high speed (1000 rpm, 25 min), wet form and dry (75℃, 0.2 MPa);

[0063] S2. Preparation of anti-counterfeiting structural layer 102: Photosensitive resin (thickness 0.08) is coated on the surface of the base layer, and a three-dimensional microstructure array is engraved by ultraviolet laser with wavelength 350nm and pulse frequency 180kHz, followed by ultraviolet curing and shaping (energy 450mJ / cm). 2 );

[0064] S3. Preparation of functional coating 103:

[0065] S3a. Magnetic iron oxide and thermochromic ink were ball-milled and dispersed (250 rpm, 1.5 h), and amphiphilic graphene quantum dots were added for esterification reaction (90 °C, 2 h).

[0066] S3b. Photochromic conductive polymer and microencapsulated fragrance are added and ultrasonically dispersed (35kHz, 25min), and a composite network is formed by utilizing the π-π stacking effect of amphiphilic graphene quantum dots;

[0067] S3c. Drying after screen printing coating (55℃, 12min);

[0068] S4. Magnetization treatment: The coated cardboard box is placed in an alternating magnetic field, with the magnetic field direction changing 10° per second, which promotes the formation of a cross-linked structure between magnetic iron oxide and amphiphilic graphene quantum dots.

[0069] An anti-counterfeiting treatment device for kraft paper boxes.

[0070] It includes a laser engraving unit 201, a magnetization processing unit 202, and a fluorescence detection unit 203;

[0071] The laser engraving unit 201 uses a 350nm ultraviolet laser with a pulse frequency of 180kHz and an engraving accuracy of ≤8μm.

[0072] The magnetization processing unit 202 uses an alternating magnetic field generator with a magnetic field strength of 0.8T, a frequency of 8Hz, and a magnetic field direction change frequency ≥4Hz.

[0073] The fluorescence detection unit 203 uses an LED light source with a wavelength of 350nm and a CMOS sensor to detect the blue fluorescence of amphiphilic graphene quantum dots and the minty odor released by the fragrance.

[0074] The engraving path of the laser engraving unit 201 is controlled by a computer, and the engraving depth is adjusted by the laser power of 10W and the pulse duration of 1ms to ensure that the spacing of the three-dimensional microstructure array is 0.3mm and the depth is 0.1mm.

[0075] An anti-counterfeiting verification method includes the following steps:

[0076] T1. Magnetic verification: Use a permanent magnet to approach the cardboard box and detect the magnetic field distortion (magnetic flux change rate ≥ 0.25T / s) generated by the synergy of magnetic iron oxide and amphiphilic graphene quantum dots;

[0077] T2. Synergistic verification using thermo-optical-chemical methods:

[0078] T2a. When heated to above 35°C, the thermochromic ink changes from colorless to blue, and the fluorescence intensity of the amphiphilic graphene quantum dots increases by 1.5 times;

[0079] T2b. Ultraviolet light irradiation triggers a sharp drop in the resistivity of the photochromic conductive polymer (≥0.5 orders of magnitude), while simultaneously releasing a minty odor;

[0080] T3. Destructive verification: If the coating is scraped off, the three-dimensional microstructure array is destroyed, causing the diffraction grating to fail, the fluorescent labeling of the amphiphilic graphene quantum dots to disappear, and the magnetic signal and electrical signal to become mismatched.

[0081] In the thermo-optical-chemical synergistic verification, the fluorescence signal of amphiphilic graphene quantum dots and the electrical signal of photochromic conductive polymer are correlated in real time through a data acquisition system to form a unique anti-counterfeiting code, with a verification accuracy of over 99.5%.

[0082] Example 2

[0083] A type of anti-counterfeiting kraft paper box.

[0084] It is composed of a base layer 101, an anti-counterfeiting structural layer 102, and a functional coating layer 103 in sequence;

[0085] The base layer 101 is made of a composite material of kraft paper fiber and nanocellulose, with a thickness of 1.4 mm;

[0086] The anti-counterfeiting structural layer 102 is a three-dimensional microstructure array formed by laser engraving, with an array spacing of 0.4 mm and a depth of 0.15 mm;

[0087] The functional coating 103 contains magnetic iron oxide microparticles, thermochromic ink, photochromic conductive polymer, microencapsulated fragrance, and amphiphilic graphene quantum dots; the amphiphilic graphene quantum dots have a particle size of 4 nm and are modified with carboxyl and amino groups on their surface.

[0088] The particle size of the magnetic iron oxide microparticles is 1.6 μm.

[0089] The mass percentages of each component in functional coating 103 are as follows: 12% magnetic iron oxide, 25% thermochromic ink, 17% photochromic conductive polymer, 8% microencapsulated fragrance, 6% amphiphilic graphene quantum dots, 1.7% sodium polyacrylate dispersant, and the balance being waterborne polyurethane resin.

[0090] The photochromic conductive polymer is a poly(3-hexylthiophene) / [6,6]-phenyl-C61-butyrate methyl ester complex.

[0091] The microencapsulated flavoring is menthol.

[0092] The three-dimensional microstructure array of the anti-counterfeiting structural layer 102 is a diffraction grating structure, with a surface coated with photosensitive resin of 0.1 mm thickness, and passes through a wavelength of 365 nm and an energy of 500 mJ / cm². 2 UV curing and shaping.

[0093] The mass ratio of kraft paper fiber to nanocellulose in the base layer 101 is 80:20, the diameter of the nanocellulose is 75nm, and the base layer is prepared by a wet molding process with a drying temperature of 80℃ and a pressure of 0.3MPa.

[0094] A manufacturing process for an anti-counterfeiting kraft paper box includes the following steps:

[0095] S1. Preparation of base layer 101: Pulp kraft paper fibers to a freeness of 40°SR, add nanocellulose and stir at high speed (1200rpm, 30min), wet form and dry (80℃, 0.3MPa);

[0096] S2. Preparation of anti-counterfeiting structural layer 102: A photosensitive resin (thickness 0.10 mm) is coated on the surface of the base layer, and a three-dimensional microstructure array is engraved by an ultraviolet laser with a wavelength of 355 nm and a pulse frequency of 200 kHz, followed by ultraviolet curing and shaping (energy 500 mJ / cm). 2 );

[0097] S3. Preparation of functional coatings, 103:

[0098] S3a. Magnetic iron oxide and thermochromic ink were ball-milled and dispersed (300 rpm, 2 h), and amphiphilic graphene quantum dots were added for esterification reaction (100 °C, 3 h).

[0099] S3b. Add photochromic conductive polymer and microencapsulated fragrance, and ultrasonically disperse (40kHz, 30min) to form a composite network by utilizing the π-π stacking effect of amphiphilic graphene quantum dots;

[0100] S3c. Drying after screen printing coating (60℃, 16min);

[0101] S4. Magnetization treatment: The coated cardboard box is placed in an alternating magnetic field, with the magnetic field direction changing 15° per second, which promotes the formation of a cross-linked structure between magnetic iron oxide and amphiphilic graphene quantum dots.

[0102] An anti-counterfeiting treatment device for kraft paper boxes.

[0103] It includes a laser engraving unit 201, a magnetization processing unit 202, and a fluorescence detection unit 203;

[0104] The laser engraving unit 201 uses a 355nm ultraviolet laser with a pulse frequency of 200kHz and an engraving accuracy of ≤8μm.

[0105] The magnetization processing unit 202 uses an alternating magnetic field generator with a magnetic field strength of 1.0T, a frequency of 10Hz, and a magnetic field direction change frequency ≥4Hz.

[0106] The fluorescence detection unit 203 uses an LED light source with a wavelength of 365nm and a CMOS sensor to detect the blue fluorescence of amphiphilic graphene quantum dots and the minty odor released by the fragrance.

[0107] The engraving path of the laser engraving unit 201 is controlled by a computer, and the engraving depth is adjusted by the laser power of 20W and the pulse duration of 3ms to ensure that the spacing of the three-dimensional microstructure array is 0.4mm and the depth is 0.15mm.

[0108] A method for verifying authenticity, characterized by comprising the following steps:

[0109] T1. Magnetic verification: Use a permanent magnet to approach the cardboard box and detect the magnetic field distortion (magnetic flux change rate ≥ 0.25T / s) generated by the synergy of magnetic iron oxide and amphiphilic graphene quantum dots;

[0110] T2. Synergistic verification using thermo-optical-chemical methods:

[0111] T2a. When heated to above 35°C, the thermochromic ink changes from colorless to blue, and the fluorescence intensity of the amphiphilic graphene quantum dots increases by 1.5-3 times;

[0112] T2b. Ultraviolet light irradiation triggers a sharp drop in the resistivity of the photochromic conductive polymer (≥0.5 orders of magnitude), while simultaneously releasing a minty odor;

[0113] T3. Destructive verification: If the coating is scraped off, the three-dimensional microstructure array is destroyed, causing the diffraction grating to fail, the fluorescent labeling of the amphiphilic graphene quantum dots to disappear, and the magnetic signal and electrical signal to become mismatched.

[0114] In the thermo-optical-chemical synergistic verification, the fluorescence signal of amphiphilic graphene quantum dots and the electrical signal of photochromic conductive polymer are correlated in real time through a data acquisition system to form a unique anti-counterfeiting code, with a verification accuracy of over 99.5%.

[0115] Example 3

[0116] A type of anti-counterfeiting kraft paper box.

[0117] It is composed of a base layer 101, an anti-counterfeiting structural layer 102, and a functional coating layer 103 in sequence;

[0118] The base layer 101 is made of a composite material of kraft paper fiber and nanocellulose, with a thickness of 1.8 mm;

[0119] The anti-counterfeiting structural layer 102 is a three-dimensional microstructure array formed by laser engraving, with an array spacing of 0.6 mm and a depth of 0.25 mm;

[0120] The functional coating 103 contains magnetic iron oxide microparticles, thermochromic ink, photochromic conductive polymer, microencapsulated fragrance, and amphiphilic graphene quantum dots; the amphiphilic graphene quantum dots have a particle size of 6 nm and are modified with carboxyl and amino groups on their surface.

[0121] The particle size of the magnetic iron oxide microparticles is 3 μm.

[0122] The mass percentages of each component in functional coating 103 are as follows: 15% magnetic iron oxide, 30% thermochromic ink, 20% photochromic conductive polymer, 10% microencapsulated fragrance, 8% amphiphilic graphene quantum dots, 3% sodium polyacrylate dispersant, and the balance being waterborne polyurethane resin.

[0123] The photochromic conductive polymer is a poly(3-hexylthiophene) / [6,6]-phenyl-C61-butyrate methyl ester complex.

[0124] The microencapsulated flavoring is menthol.

[0125] The three-dimensional microstructure array of the anti-counterfeiting structural layer 102 is a diffraction grating structure, with a surface coated with photosensitive resin of 0.1 mm thickness, and passes through a wavelength of 365 nm and an energy of 500 mJ / cm². 2 UV curing and shaping.

[0126] The mass ratio of kraft paper fiber to nanocellulose in the base layer 101 is 80:20, the diameter of the nanocellulose is 100nm, and the base layer is prepared by a wet molding process with a drying temperature of 80℃ and a pressure of 0.3MPa.

[0127] A manufacturing process for an anti-counterfeiting kraft paper box includes the following steps:

[0128] S1. Preparation of base layer 101: Pulp kraft paper fibers to a freeness of 45°SR, add nanocellulose and stir at high speed (1400rpm, 35min), wet form and dry (85℃, 0.4MPa);

[0129] S2. Preparation of anti-counterfeiting structural layer 102: A photosensitive resin (thickness 0.12 mm) is coated on the surface of the base layer, and a three-dimensional microstructure array is engraved by an ultraviolet laser with a wavelength of 360 nm and a pulse frequency of 220 kHz, followed by ultraviolet curing and shaping (energy 550 mJ / cm). 2 );

[0130] S3. Preparation of functional coating 103:

[0131] S3a. Magnetic iron oxide and thermochromic ink were ball-milled and dispersed (350 rpm, 2.5 h), and amphiphilic graphene quantum dots were added for esterification reaction (110 °C, 4 h).

[0132] S3b. Photochromic conductive polymer and microencapsulated fragrance are added and ultrasonically dispersed (45kHz, 35min), and a composite network is formed by utilizing the π-π stacking effect of amphiphilic graphene quantum dots.

[0133] S3c. Drying after screen printing coating (65℃, 18min);

[0134] S4. Magnetization treatment: The coated cardboard box is placed in an alternating magnetic field, with the magnetic field direction changing 20° per second, which promotes the formation of a cross-linked structure between magnetic iron oxide and amphiphilic graphene quantum dots.

[0135] An anti-counterfeiting treatment device for kraft paper boxes.

[0136] It includes a laser engraving unit 201, a magnetization processing unit 202, and a fluorescence detection unit 203;

[0137] The laser engraving unit 201 uses a 360nm ultraviolet laser with a pulse frequency of 220kHz and an engraving accuracy of ≤8μm.

[0138] The magnetization processing unit 202 uses an alternating magnetic field generator with a magnetic field strength of 1.2T, a frequency of 12Hz, and a magnetic field direction change frequency ≥4Hz.

[0139] The fluorescence detection unit 203 uses an LED light source with a wavelength of 380nm and a CMOS sensor to detect the blue fluorescence of amphiphilic graphene quantum dots and the minty odor released by the fragrance.

[0140] The engraving path of the laser engraving unit 201 is controlled by a computer, and the engraving depth is adjusted by the laser power of 30W and the pulse duration of 5ms to ensure that the spacing of the three-dimensional microstructure array is 0.5mm and the depth is 0.2mm.

[0141] An anti-counterfeiting verification method includes the following steps:

[0142] T1. Magnetic verification: Use a permanent magnet to approach the cardboard box and detect the magnetic field distortion (magnetic flux change rate ≥ 0.25T / s) generated by the synergy of magnetic iron oxide and amphiphilic graphene quantum dots;

[0143] T2. Synergistic verification using thermo-optical-chemical methods:

[0144] T2a. When heated to above 35°C, the thermochromic ink changes from colorless to blue, and the fluorescence intensity of the amphiphilic graphene quantum dots increases by 1.5-3 times;

[0145] T2b. Ultraviolet light irradiation triggers a sharp drop in the resistivity of the photochromic conductive polymer (≥0.5 orders of magnitude), while simultaneously releasing a minty odor;

[0146] T3. Destructive verification: If the coating is scraped off, the three-dimensional microstructure array is destroyed, causing the diffraction grating to fail, the fluorescent labeling of the amphiphilic graphene quantum dots to disappear, and the magnetic signal and electrical signal to become mismatched.

[0147] In the thermo-optical-chemical synergistic verification, the fluorescence signal of amphiphilic graphene quantum dots and the electrical signal of photochromic conductive polymer are correlated in real time through a data acquisition system to form a unique anti-counterfeiting code, with a verification accuracy of over 99.5%.

[0148] The following is a table of comparative experimental data.

[0149]

[0150]

[0151] From the data above, we can conclude that:

[0152] Hydrogen bond dispersion stability: Ordinary cardboard boxes do not contain AGQDs, and the sedimentation rate of Fe3O4 particles is as high as 5%, while the embodiment of the present invention controls the sedimentation rate to 0.5%-2% through the hydrogen bond effect of AGQDs.

[0153] Thermal response time of thermochromic ink: Ordinary cardboard boxes rely solely on the properties of the thermochromic ink itself, with a response time of 10 seconds; this invention shortens the time to 5-8 seconds through the esterification reaction of AGQDs.

[0154] Resistivity reduction: Ordinary cardboard photochromic polymers without AGQDs only reduce resistivity by 0.5 orders of magnitude; this invention achieves a reduction of 1.2-1.8 orders of magnitude through π-π stacking.

[0155] Microcapsule thermal stability: Ordinary cardboard microcapsules do not have AGQDs crosslinking, and their bursting temperature is not increased; the present invention increases the bursting temperature by 11%-33% through AGQDs crosslinking reaction.

[0156] Magnetothermal heating time: Ordinary cardboard boxes without AGQDs synergy require 20s to heat up to 45℃ under a 1.0T magnetic field; This invention, through the π electrons of AGQDs and the eddy current thermal synergy of Fe3O4, shortens the time to 7-12s.

[0157] Fluorescence-electrical signal verification success rate: Ordinary cardboard boxes without AGQDs fluorescent markings have a verification success rate of only 80%; this invention achieves a success rate of 98.2%-99.8% by correlating the fluorescence and electrical signals of AGQDs.

[0158] The AGQDs technology of this invention is significantly superior to ordinary anti-counterfeiting cartons in terms of dispersion stability, thermal response speed, charge transfer efficiency, thermal stability, and anti-counterfeiting verification accuracy.

[0159] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A counterfeit-proof kraft paper box, characterized in that: It is composed of a base layer (101), an anti-counterfeiting structural layer (102), and a functional coating layer (103) in sequence; The base layer (101) is made of a composite material of kraft paper fiber and nanocellulose, with a thickness of 1.0-1.8 mm; The anti-counterfeiting structural layer (102) is a three-dimensional microstructure array formed by laser engraving, with an array spacing of 0.2-0.6 mm and a depth of 0.05-0.25 mm; The functional coating (103) comprises magnetic iron oxide microparticles, thermochromic ink, photochromic conductive polymer, microencapsulated fragrance, and amphiphilic graphene quantum dots; the amphiphilic graphene quantum dots have a particle size of 2-6 nm and are modified with carboxyl and amino groups on their surface.

2. The anti-counterfeiting kraft paper box according to claim 1, characterized in that: The magnetic iron oxide microparticles have a particle size of 0.3-3 μm.

3. The anti-counterfeiting kraft paper box according to claim 1, characterized in that: The mass percentage of each component in the functional coating (103) is as follows: 10%-15% magnetic iron oxide, 20%-30% thermochromic ink, 15%-20% photochromic conductive polymer, 5%-10% microencapsulated fragrance, 3%-8% amphiphilic graphene quantum dots, 0.5%-3% sodium polyacrylate dispersant, and the balance is waterborne polyurethane resin.

4. The anti-counterfeiting kraft paper box according to claim 1, characterized in that: The photochromic conductive polymer is a poly(3-hexylthiophene) / [6,6]-phenyl-C61-butyrate methyl ester complex.

5. The anti-counterfeiting kraft paper box according to claim 1, characterized in that: The microencapsulated flavoring is menthol.

6. The anti-counterfeiting kraft paper box according to claim 1, characterized in that: The three-dimensional microstructure array of the anti-counterfeiting structural layer (102) is a diffraction grating structure, with a surface coated with photosensitive resin of 0.1 mm thickness, and passes through a wavelength of 365 nm and an energy of 500 mJ / cm². 2 UV curing and shaping.

7. The anti-counterfeiting kraft paper box according to claim 1, characterized in that: The mass ratio of kraft paper fiber to nanocellulose in the base layer (101) is 80:20, the diameter of the nanocellulose is 50-100nm, and the base layer is prepared by a wet molding process with a drying temperature of 80℃ and a pressure of 0.3MPa.

8. The anti-counterfeiting kraft paper box according to claim 1, characterized in that, The preparation process includes the following steps: S1. Preparation of the base layer (101): Pulp kraft paper fibers to a freeness of 35°SR, add nanocellulose and stir at high speed (1000-1400rpm, 25-35min), wet form and dry, drying temperature 75-85℃, pressure 0.2-0.4MPa; S2. Preparation of anti-counterfeiting structural layer (102): Photosensitive resin with a thickness of 0.08-0.12 mm is coated on the surface of the base layer. The three-dimensional microstructure array is engraved by ultraviolet laser with a wavelength of 350-360 nm and a pulse frequency of 180-220 kHz, and then cured and shaped by ultraviolet light. S3. Preparation of functional coating (103): S3a. Magnetic iron oxide and thermochromic ink are ball-milled and dispersed at a speed of 250-350 rpm for 1.5-2.5 h. Amphiphilic graphene quantum dots are added for esterification reaction at a temperature of 90-110℃ for 2-4 h. S3b. Photochromic conductive polymer and microencapsulated fragrance are added, ultrasonically dispersed, and a composite network is formed by the π-π stacking effect of amphiphilic graphene quantum dots; S3c. After screen printing and coating, dry at a temperature of 55-65℃ for 12-18 minutes. S4. Magnetization treatment: The coated cardboard box is placed in an alternating magnetic field, with the magnetic field direction changing 10-20° per second, which promotes the formation of a cross-linked structure between magnetic iron oxide and amphiphilic graphene quantum dots.

9. An anti-counterfeiting processing device for an anti-counterfeiting kraft paper box as described in claim 1, characterized in that: It includes a laser engraving unit (201), a magnetization processing unit (202), and a fluorescence detection unit (203); The laser engraving unit (201) uses an ultraviolet laser with a wavelength of 350-360nm, a pulse frequency of 180-220kHz, and an engraving accuracy of ≤8μm; The magnetization processing unit (202) adopts an alternating magnetic field generator with a magnetic field strength of 0.8-1.2T, a frequency of 8-12Hz, and a magnetic field direction change frequency ≥4Hz. The fluorescence detection unit (203) uses an LED light source with a wavelength of 350-380nm and a CMOS sensor to detect the blue fluorescence of the amphiphilic graphene quantum dots and the minty odor released by the fragrance.

10. The anti-counterfeiting processing device for an anti-counterfeiting kraft paper box according to claim 9, characterized in that: The engraving path of the laser engraving unit (201) is controlled by a computer, and the engraving depth is adjusted by the laser power of 10-30W and the pulse duration of 1-5ms to ensure that the spacing of the three-dimensional microstructure array is 0.3-0.5mm and the depth is 0.1-0.2mm.

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