An anti-counterfeiting film with a color-changing effect and its preparation method

Abstract

The present invention discloses an anti-counterfeiting film with a color-changing effect and a preparation method thereof, including a coating layer and an aluminum plating layer. The coating layer comprises the following raw materials: a polymerizable macromolecular surfactant, nanocellulose, N-methyldiethanolamine, acrylic acid, 2-hydroxyethyl methacrylate, sodium pyrrolidone carboxylate, polyethylene glycol p-isooctylphenyl ether, and 2,2'-azobis(2-isopropylimidazoline). The preparation of the coating layer includes the following steps: First step, add the polymerizable macromolecular surfactant into water, add glacial acetic acid, and dropwise add it to a mixture of N-methyldiethanolamine, acrylic acid, and 2-hydroxyethyl methacrylate, and dropwise add 2,2'-azobis(2-isopropylimidazoline) to obtain emulsion Z; Second step, add sodium pyrrolidone carboxylate and polyethylene glycol p-isooctylphenyl ether, and continue stirring to obtain emulsion Q; Third step, coat emulsion Q on a substrate, and after air-cooling and drying, a coating layer is obtained. The polymerizable macromolecular surfactant is applied to the polymerization of polyacrylic acid, and it will not migrate after the film layer is dried.

Description

Technical Field

[0001] The present invention belongs to the technical field of film layer production, and specifically relates to an anti-counterfeiting film with a color-changing effect and a preparation method thereof. Background Art

[0002] Currently, there are mainly three types of anti-counterfeiting labels popular in the market: one is printed with special ink and needs to be identified by special instruments or detection means; the second is to use anti-counterfeiting codes and query through anti-counterfeiting phones or the Internet;

[0003] The third is to make a holographic anti-counterfeiting label through laser holographic imaging. The cost of using the above anti-counterfeiting codes and holographic anti-counterfeiting labels is relatively high, while the current ink printing method has a single anti-counterfeiting function, is easy to identify and is also easy to imitate, so the authenticity is not strong.

[0004] The anti-counterfeiting of the ink printing method utilizes the optical effect of colorants. For example, based on the composition of colorant platelets, interference, reflection and absorption phenomena, an image with colors and brightness changing with the viewing angle is generated. Among them, the optical interference color-changing film is designed according to the optical interference principle of a multi-layer composite film. When light is incident on the anti-counterfeiting film system structure, due to different combinations of physical parameters such as the material properties and thickness of each layer of the film, constructive and destructive interference of light with different wavelengths will occur. When observed from different angles, the color tone of the reflected light can be seen to change. With the maturity of this technology, the imitation of the above optical interference color-changing film has become relatively easy. In order to increase the difficulty of imitation, the prior art generally enhances the significance of anti-counterfeiting color change by increasing the polarization characteristics, electromagnetic characteristics of the material, and different ratios of chemical materials. However, the above methods not only increase the difficulty of the manufacturing process, but also increase the printing cost.

[0005] It can be seen that in order to increase the difficulty of imitation, the anti-counterfeiting films of the prior art adopt a method with a more difficult manufacturing process and higher cost. At the same time, for the anti-counterfeiting film mainly composed of polyacrylic resin, since a large amount of carboxyl groups are contained in polyacrylic acid and the hydrophilicity of the carboxyl groups is good, the water resistance of the organic film layer is poor. And surfactants need to be used in the polymerization process. During the film-forming process of the emulsion, as the solvent continuously volatilizes, the surfactants will migrate to the surface of the film layer, thereby affecting the use effect of the film layer. Summary of the Invention

[0006] The purpose of the present invention is to provide an anti-counterfeiting film with a color-changing effect and a preparation method thereof to overcome the technical problems proposed in the above background art.

[0007] The object of the present invention can be achieved by the following technical solutions: An anti-counterfeiting film with a color-changing effect, comprising a coating and an aluminum plating layer. The coating comprises the following raw materials in parts by weight: 10-15 parts of a polymerizable macromolecular surfactant, 30-40 parts of nanocellulose, 1-3 parts of N-methyldiethanolamine, 100-120 parts of acrylic acid, 150-180 parts of hydroxyethyl methacrylate, 5-7 parts of glacial acetic acid, 0.5-0.8 parts of sodium pyrrolidone carboxylate, 0.2-0.4 parts of polyethylene glycol p-isooctylphenyl ether, 5-10 parts of azodiisopropylimidazoline, 30-40 parts of ethyl acetate, 10-13 parts of methyl ethyl ketone, 5-8 parts of n-propyl ester, 15-18 parts of methyl ether, and 30-45 parts of water;

[0008] The preparation of the polymerizable macromolecular surfactant comprises the following steps:

[0009] Step S11: Add methyl ethyl ketone and azodiisobutyronitrile into a flask, seal the flask, perform a vacuum pumping operation on the flask, then fill it with nitrogen to normal pressure, and continue to pump vacuum. Repeat this cycle 3 times for nitrogen replacement to make the reaction proceed under the protection of nitrogen. Heat to 75 °C, dropwise add dimethylaminoethyl methacrylate and cobalt oxime boron fluoride complex to prepare a fragment of the first block polymer, keep the reaction at a constant temperature for 2 h, cool down to zero degree, and place it in a vacuum drying oven to remove the solvent and unreacted monomers to obtain Intermediate 1;

[0010] Step S12: Mix Intermediate 1, methyl ethyl ketone and isopropyl alcohol, add azodiisobutyronitrile, and perform nitrogen replacement. The nitrogen replacement process is the same as that in Step S11. Under the condition of constant temperature at 75 °C, add butyl methacrylate and cobalt oxime boron fluoride complex dissolved in methyl ethyl ketone, and add another monomer to prepare a block copolymer. React for 5 h, cool down to zero degree, add it to n-hexane, wash the precipitate to obtain the polymerizable macromolecular surfactant.

[0011] Further, the dosage ratio of methyl ethyl ketone, azodiisobutyronitrile, dimethylaminoethyl methacrylate and cobalt oxime boron fluoride complex in Step S11 is 150 mL: 1.5 g: 112 g: 3 g; the dosage ratio of Intermediate 1, methyl ethyl ketone, isopropyl alcohol and azodiisobutyronitrile in Step S12 is 80 g: 360 mL: 58 mL: 2 g; the dosage ratio of butyl methacrylate, methyl ethyl ketone, cobalt oxime boron fluoride complex and n-hexane in Step S12 is 156 g: 423 mL: 3 g: 1100 mL.

[0012] Further, the preparation of nanocellulose comprises the following steps:

[0013] Step S21: Add dry wood powder into toluene and ethanol to obtain a mixed solution X. Add the mixed solution X into a Soxhlet extractor, extract at 90 °C for 7 h, and dry in an oven at 40 °C for 14 h to obtain Cellulose A;

[0014] Step S22: Add cellulose A into the reaction tank, add distilled water, glacial acetic acid and sodium chlorite into the reaction tank, heat the reaction tank to 78 °C with stirring under sealed conditions, and add glacial acetic acid and sodium chlorite into the reaction tank every 1.5 h until cellulose A turns white. Filter and wash until neutral to obtain cellulose B;

[0015] Step S23: Add cellulose B into the potassium hydroxide solution, heat and stir at a constant temperature of 100 °C for 4 h, filter and wash until neutral to prepare cellulose C;

[0016] Step S24: Configure cellulose C into an aqueous suspension with a mass concentration of 6%, grind it in a grinding device for 15 min at a grinding speed of 1200 rpm to obtain nanocellulose.

[0017] Further, in step S21, the dosage ratio of dry wood powder, toluene and ethanol is 3 g: 60 mL: 35 mL, and the mesh number of dry wood powder is 30 - 50 meshes; in step S22, the dosage ratio of cellulose A, distilled water, glacial acetic acid and sodium chlorite is 1.3 g: 30 mL: 2 g: 3 g, and the dosage ratio of the added glacial acetic acid and sodium chlorite in step S22 is 1.3 g: 2 g; in step S23, the dosage ratio of the potassium hydroxide solution to cellulose B is 45 mL: 1 g, and the mass concentration is 6%.

[0018] Further, the preparation of the coating includes the following steps: Step S31: Add the polymerizable macromolecular surfactant into water, add glacial acetic acid, adjust the pH of the solution to obtain solution Y. Under stirring conditions, drop solution Y into the mixture of N - methyldiethanolamine, acrylic acid and 2 - hydroxyethyl methacrylate, continue stirring for 30 min, heat to 75 °C, drop azodiisopropylimidazoline, and react for 5 h to obtain emulsion Z;

[0019] Step S32: Add ethyl acetate, methyl ethyl ketone, n - propyl ester and methyl ether into the reaction kettle, start stirring, add nanocellulose, heat with steam to 50 °C, add emulsion Z, raise the temperature to 78 °C, and keep warm for 2.5 - 3.5 h;

[0020] Step S33: Cool down to 36 °C, add sodium pyrrolidone carboxylate and polyethylene glycol p - octylphenol ether, continue stirring for 0.8 - 1.2 h to obtain emulsion Q;

[0021] Step S34: Coat emulsion Q on the substrate with a ceramic roller, and obtain the coating after air - cooling and drying. The substrate is a metal plate with a smooth surface, which is used for preparing the coating and can be used repeatedly.

[0022] A preparation method of an anti - counterfeiting film with a color - changing effect includes the following steps:

[0023] Step S41, molding the coating with a seamless molding machine to obtain a coating 1;

[0024] Step S42: The aluminum wire is evaporated into vapor by an evaporation boat and adheres to the surface of the coating 1 to form an aluminum coating, thereby obtaining an anti-counterfeiting film.

[0025] Furthermore, in step S41, the molding temperature range of the seamless molding machine is 170-190°C, and the molding pressure range is 2.5-3.5MPa; step S42 is carried out in a vacuum chamber, and the heating temperature of the evaporation boat is 1400-1500°C.

[0026] Beneficial effects of the present invention: the present invention adds acrylic resin to dispersed nanocellulose and reacts under heating conditions. Since cellulose has many active hydroxyl groups, they will partially condense with the carboxyl groups on the acrylic resin at high temperature. The generated water molecules will be separated from the reaction system due to the presence of organic solvents, so the reaction process will proceed in the direction of dehydration. After condensation, ester bonds will be generated between cellulose and acrylic resin to partially couple. The cellulose is dispersed between the acrylic resins and partially coupled with the acrylic resin, which changes the arrangement of the original acrylic resin. Therefore, after the composite coating A forms a coating, the coating presents different colors at different optical angles, thereby having a unique color-changing effect.

[0027] A coating machine is used to form an aluminum coating on the coating surface, which makes the coating have a bright metallic luster, excellent gas and light barrier properties, and good moisture resistance, heat resistance, and puncture resistance. The light barrier performance of the aluminum coating can better bring out the optical color-changing effect of the color-changing film.

[0028] The anti-counterfeiting film of the present invention can present different colors at different angles, has good color-changing effect and anti-counterfeiting performance, adopts cellulose as the main raw material, and is prepared by the principle of partial condensation with acrylic resin. The preparation process is simple, the cost of raw materials is low, and it is conducive to the promotion and application of anti-counterfeiting technology; the present invention uses a catalytic chain transfer polymerization method to prepare a block copolymer of dimethylaminoethyl methacrylate and butyl methacrylate with a cationic double bond end-capping method, and uses the molecular structure of a polymerizable terminal carbon-carbon double bond to apply the block copolymer of dimethylaminoethyl methacrylate and butyl methacrylate as a polymerizable macromolecular surfactant to the emulsion polymerization of polyacrylic acid, and synthesizes an emulsion with excellent stability, high solid content and excellent water resistance. After the film layer is dried, the polymerizable macromolecular surfactant will not migrate, and the use performance is stable. DETAILED DESCRIPTION

[0029] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

[0030] Example 1

[0031] Prepare a polymerizable macromolecular surfactant:

[0032] Step S11: Add methyl ethyl ketone and azobisisobutyronitrile into a flask, seal the flask, perform a vacuum pumping operation on the flask, and then fill it with nitrogen to normal pressure, continue to pump vacuum, and repeat this cycle 3 times for nitrogen replacement to make the reaction proceed under the protection of nitrogen. Heat to 75 °C, dropwise add dimethylaminoethyl methacrylate and cobalt oxime boron fluoride complex to prepare a fragment of the first block polymer, react at a constant temperature for 2 h, cool down to zero degree, and place it in a vacuum drying oven to remove the solvent and unreacted monomers to obtain Intermediate 1;

[0033] Step S12: Mix Intermediate 1, methyl ethyl ketone and isopropyl alcohol, add azobisisobutyronitrile, and perform nitrogen replacement. The nitrogen replacement process is the same as that in Step S11. Under the condition of constant temperature at 75 °C, add butyl methacrylate and cobalt oxime boron fluoride complex dissolved in methyl ethyl ketone, and add another monomer to prepare a block copolymer. React for 5 h, cool down to zero degree, add it to n-hexane, wash the precipitate to obtain a polymerizable macromolecular surfactant.

[0034] The dosage ratio of methyl ethyl ketone, azobisisobutyronitrile, dimethylaminoethyl methacrylate and cobalt oxime boron fluoride complex in Step S11 is 150 mL: 1.5 g: 112 g: 3 g; the dosage ratio of Intermediate 1, methyl ethyl ketone, isopropyl alcohol and azobisisobutyronitrile in Step S12 is 80 g: 360 mL: 58 mL: 2 g; the dosage ratio of butyl methacrylate, methyl ethyl ketone, cobalt oxime boron fluoride complex and n-hexane in Step S12 is 156 g: 423 mL: 3 g: 1100 mL.

[0035] Example 2

[0036] Prepare nanocellulose:

[0037] Step S21: Add dry wood powder into toluene and ethanol to obtain a mixed solution X. Add the mixed solution X into a Soxhlet extractor and extract it at 90 °C for 7 h, and dry it in an oven at 40 °C for 14 h to obtain Cellulose A;

[0038] Step S22: Add cellulose A into the reaction tank, add distilled water, glacial acetic acid and sodium chlorite into the reaction tank, heat the reaction tank to 78°C with stirring under sealed conditions, and add glacial acetic acid and sodium chlorite to the reaction tank every 1.5 h until cellulose A turns white, filter and wash until neutral to obtain cellulose B;

[0039] Step S23: Add cellulose B into the potassium hydroxide solution, heat and stir at a constant temperature of 100°C for 4 h, filter and wash until neutral to prepare cellulose C;

[0040] Step S24: Configure cellulose C into a 6% aqueous suspension, grind it in a grinding device for 15 min at a grinding speed of 1200 rpm to obtain nanocellulose.

[0041] In step S21, the dosage ratio of dry wood powder, toluene and ethanol is 3 g: 60 mL: 35 mL, and the mesh number of dry wood powder is 30 - 50 mesh; in step S22, the dosage ratio of cellulose A, distilled water, glacial acetic acid and sodium chlorite is 1.3 g: 30 mL: 2 g: 3 g, and the dosage ratio of supplementary glacial acetic acid and sodium chlorite added in step S22 is 1.3 g: 2 g; in step S23, the dosage of sodium hydroxide solution is 45 mL and the concentration is 6%.

[0042] Example 3

[0043] Preparation of coating

[0044] Step S31: Add the polymerizable macromolecular surfactant into water, add glacial acetic acid, adjust the pH of the solution to obtain solution Y, under stirring conditions, drop solution Y into the mixture of N-methyldiethanolamine, acrylic acid and 2-hydroxyethyl methacrylate, continue stirring for 30 min, heat to 75°C, drop azodiisopropylimidazoline, and react for 5 h to obtain emulsion Z;

[0045] Step S32: Add ethyl acetate, butanone, n-propyl ester and methyl ether into the reaction kettle, start stirring, add nanocellulose, heat with steam to 50°C, add emulsion Z, raise the temperature to 78°C, and keep warm for 2.5 h;

[0046] Step S33: Cool down to 36°C, add sodium pyrrolidone carboxylate and polyethylene glycol p-isooctyl phenyl ether, continue stirring for 0.8 h to obtain emulsion Q;

[0047] Step S34: Coat emulsion Q on the substrate with a ceramic roller, and obtain the coating after air-cooling and drying. The substrate is a metal plate with a smooth surface and can be used repeatedly for preparing the coating.

[0048] The coating comprises the following raw materials in parts by weight: 10 parts of polymerizable macromolecular surfactant, 30 parts of nanocellulose, 1 part of N-methyldiethanolamine, 100 parts of acrylic acid, 150 parts of hydroxyethyl methacrylate, 5 parts of glacial acetic acid, 0.5 part of sodium pyrrolidone carboxylate, 0.2 part of polyethylene glycol p-isooctylphenyl ether, 5 parts of azodiisopropylimidazoline, 30 parts of ethyl acetate, 10 parts of methyl ethyl ketone, 5 parts of n-propyl ester, 15 parts of methyl ether and 30 parts of water.

[0049] Example 4

[0050] Preparation of the coating

[0051] Step S31: Add the polymerizable macromolecular surfactant to water, add glacial acetic acid, adjust the pH of the solution to obtain solution Y. Under stirring conditions, drop solution Y into the mixture of N-methyldiethanolamine, acrylic acid and hydroxyethyl methacrylate, continue stirring for 30 min, heat to 75 °C, dropwise add azodiisopropylimidazoline, and react for 5 h to obtain emulsion Z;

[0052] Step S32: Add ethyl acetate, methyl ethyl ketone, n-propyl ester and methyl ether to the reaction kettle, start stirring, add nanocellulose, heat with steam to 50 °C, add emulsion Z, raise the temperature to 78 °C, and keep warm for 3 h;

[0053] Step S33: Cool down to 36 °C, add sodium pyrrolidone carboxylate and polyethylene glycol p-isooctylphenyl ether, continue stirring for 1.0 h to obtain emulsion Q;

[0054] Step S34: Coat emulsion Q on the substrate with a ceramic roller, and obtain the coating after air-cooling and drying. The substrate is a metal plate with a smooth surface, which is used for preparing the coating and can be used repeatedly.

[0055] The coating comprises the following raw materials in parts by weight: 12 parts of polymerizable macromolecular surfactant, 35 parts of nanocellulose, 2 parts of N-methyldiethanolamine, 110 parts of acrylic acid, 170 parts of hydroxyethyl methacrylate, 6 parts of glacial acetic acid, 0.6 part of sodium pyrrolidone carboxylate, 0.3 part of polyethylene glycol p-isooctylphenyl ether, 7 parts of azodiisopropylimidazoline, 35 parts of ethyl acetate, 12 parts of methyl ethyl ketone, 6 parts of n-propyl ester, 17 parts of methyl ether and 40 parts of water.

[0056] Example 5

[0057] Preparation of the coating

[0058] Step S31: Add the polymerizable macromolecular surfactant to water, add glacial acetic acid, adjust the pH of the solution to obtain solution Y. Under stirring conditions, drop solution Y into the mixture of N-methyldiethanolamine, acrylic acid and hydroxyethyl methacrylate, continue stirring for 30 min, heat to 75 °C, dropwise add azodiisopropylimidazoline, and react for 5 h to obtain emulsion Z;

[0059] Step S32: Add ethyl acetate, methyl ethyl ketone, n-propyl acetate and methyl ether into the reaction kettle, start stirring, add nanocellulose, introduce steam to heat to 50°C, add emulsion Z, raise the temperature to 78°C, and keep the temperature for 3.5 h;

[0060] Step S33: Cool down to 36°C, add sodium pyrrolidone carboxylate and polyethylene glycol p-isooctylphenyl ether, and continue stirring for 1.2 h to obtain emulsion Q;

[0061] Step S34: Coat emulsion Q on the substrate with a ceramic roller, and obtain a coating after air-cooling and drying. The substrate is a metal plate with a smooth surface, which is used for preparing the coating and can be used repeatedly.

[0062] The coating comprises the following raw materials in parts by weight: 15 parts of polymerizable macromolecular surfactant, 40 parts of nanocellulose, 3 parts of N-methyldiethanolamine, 120 parts of acrylic acid, 180 parts of hydroxyethyl methacrylate, 7 parts of glacial acetic acid, 0.8 part of sodium pyrrolidone carboxylate, 0.4 part of polyethylene glycol p-isooctylphenyl ether, 10 parts of azodiisopropylimidazoline, 40 parts of ethyl acetate, 13 parts of methyl ethyl ketone, 8 parts of n-propyl acetate, 18 parts of methyl ether and 45 parts of water.

[0063] Example 6

[0064] Prepare an anti-counterfeiting film with a color-changing effect:

[0065] Step S41: Perform embossing on the coating with a seam-free embossing machine to obtain coating 1;

[0066] Step S42: Evaporate aluminum wire into vapor through an evaporation boat, and form an aluminum coating on the surface of coating 1 to obtain the anti-counterfeiting film.

[0067] In step S41, the embossing temperature range of the seam-free embossing machine is 170°C, and the embossing pressure range is 2.5 MPa; step S42 is carried out in a vacuum chamber, and the heating temperature of the evaporation boat is 1400°C.

[0068] Example 7

[0069] Prepare an anti-counterfeiting film with a color-changing effect:

[0070] Step S41: Perform embossing on the coating with a seam-free embossing machine to obtain coating 1;

[0071] Step S42: Evaporate aluminum wire into vapor through an evaporation boat, and form an aluminum coating on the surface of coating 1 to obtain the anti-counterfeiting film.

[0072] In step S41, the embossing temperature range of the seam-free embossing machine is 180°C, and the embossing pressure range is 3 MPa; step S42 is carried out in a vacuum chamber, and the heating temperature of the evaporation boat is 1450°C.

[0073] Example 8

[0074] Prepare an anti-counterfeiting film with a color-changing effect:

[0075] Step S41: The coating is embossed by a seamless embossing press to obtain Coating 1;

[0076] Step S42: Aluminum wire is evaporated into vapor through an evaporation boat and adheres to the surface of Coating 1 to form an aluminum coating, obtaining the anti-counterfeiting film.

[0077] In Step S41, the embossing temperature range of the seamless embossing press is 190 °C, and the embossing pressure range is 3.5 MPa; Step S42 is carried out in a vacuum chamber, and the heating temperature of the evaporation boat is 1500 °C.

[0078] The aluminum wire continuously fed onto the evaporation boat is evaporated into aluminum vapor, and the aluminum vapor is cooled and deposited, and the aluminum is evenly sprayed on the surface of the coating to form a coating.

[0079] A coating is formed on the surface of the coating through a coating machine, so that the coating has a bright metallic luster, excellent gas and light barrier properties, and good moisture-proof, heat-resistant, and puncture-resistant properties. The light barrier property of the coating can better set off the optical color-changing effect of the color-changing film.

[0080] Comparative Example 1: Do not implement the preparation step of the polymerizable macromolecular surfactant, and replace the polymerizable macromolecular surfactant with OEMD-20 surfactant.

[0081] Comparative Example 2: Do not implement the preparation step of nanocellulose.

[0082] The light barrier property of the anti-counterfeiting film was detected. The anti-counterfeiting film was placed in an ultraviolet absorption photometer to detect the light transmittance of the film layer, and the following data was obtained:

[0083] Table 1 Data table for detecting the light barrier property of the anti-counterfeiting film

[0084]

[0085] As can be seen from the above table, in the visible light range, the anti-counterfeiting film prepared by the method of the present invention has good light barrier properties, and most of the light is blocked by the anti-counterfeiting film. Then, the water resistance of the anti-counterfeiting film was detected. A 1 cm × 1 cm film layer was stirred and dissolved in water for 24 h, and then the solution was filtered, and the obtained solid was dried and weighed to obtain the weight M 1 , the original weight of the film layer is M, and the obtained data is summarized in the following table. As can be seen from the following table, the water resistance of the film layer added with the polymerizable macromolecular surfactant has been significantly improved, thus ensuring the use effect of the film layer.

[0086] Table 2 Data Sheet for Water Resistance Test of Anti-Counterfeiting Film

[0087]

[0088] In the description of this specification, the descriptions referring to terms such as "one embodiment", "example", "specific example", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0089] The above content is only an example and illustration of the structure of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar ways to replace them. As long as they do not deviate from the structure of the invention or exceed the scope defined by this claims, they should all fall within the protection scope of the present invention.

Claims

1. An anti-counterfeiting film with a color-changing effect, comprising a coating and an aluminum plating layer, characterized in that, the coating comprises raw materials in the following parts by weight: 10-15 parts of polymerizable macromolecular surfactant, 30-40 parts of nanocellulose, 1-3 parts of N-methyldiethanolamine, 100-120 parts of acrylic acid, 150-180 parts of hydroxyethyl methacrylate, 5-7 parts of glacial acetic acid, 0.5-0.8 part of sodium pyrrolidone carboxylate, 0.2-0.4 part of polyethylene glycol p-isooctylphenyl ether, 5-10 parts of azodiisopropylimidazoline, 30-40 parts of ethyl acetate, 10-13 parts of butanone, 5-8 parts of n-propyl ester, 15-18 parts of methyl ether, and 30-45 parts of water; the polymerizable macromolecular surfactant is prepared by the following steps: Step S11: Add butanone and azodiisobutyronitrile into a flask, seal the flask, conduct nitrogen replacement, heat to 75 °C, dropwise add dimethylaminoethyl methacrylate and cobalt oxime boron fluoride complex, react at a constant temperature for 2 h, cool to 0 °C, and remove the solvent and unreacted monomers under vacuum to obtain Intermediate 1; Step S12: Mix Intermediate 1, butanone and isopropanol, add azodiisobutyronitrile, conduct nitrogen replacement, under the condition of constant temperature at 75 °C, add butyl methacrylate and cobalt oxime boron fluoride complex dissolved in butanone, react for 5 h, cool to 0 °C, add to n-hexane, wash the precipitate to obtain the polymerizable macromolecular surfactant; The dosage ratio of butanone, azodiisobutyronitrile, dimethylaminoethyl methacrylate and cobalt oxime boron fluoride complex in Step S11 is 150 mL: 1.5 g: 112 g: 3 g; the dosage ratio of Intermediate 1, butanone, isopropanol and azodiisobutyronitrile in Step S12 is 80 g: 360 mL: 58 mL: 2 g; the dosage ratio of butyl methacrylate, butanone, cobalt oxime boron fluoride complex and n-hexane in Step S12 is 156 g: 423 mL: 3 g: 1100 mL.

2. An anti-counterfeiting film with a color-changing effect according to claim 1, characterized in that, the coating is made by the following steps: Step S31: Add the polymerizable macromolecular surfactant into water, add glacial acetic acid to obtain Solution Y, under the condition of stirring, drop Solution Y into the mixture of N-methyldiethanolamine, acrylic acid and hydroxyethyl methacrylate, continue stirring for 30 min, heat to 75 °C, dropwise add azodiisopropylimidazoline, and react for 5 h to obtain Emulsion Z; Step S32: Add ethyl acetate, butanone, n-propyl ester and methyl ether into a reaction kettle, start stirring, add nanocellulose, heat to 50 °C by introducing steam, add Emulsion Z, raise the temperature to 78 °C, and keep warm for 2.5-3.5 h; Step S33: Cool to 36 °C, add sodium pyrrolidone carboxylate and polyethylene glycol p-isooctylphenyl ether, continue stirring for 0.8-1.2 h to obtain Emulsion Q; Step S34: Coat Emulsion Q on a substrate with a ceramic roller, and dry it by air cooling to obtain the coating.

3. A preparation method of an anti-counterfeiting film with a color-changing effect according to claim 1, characterized in that, it comprises the following steps: Step S41: The coating is embossed by a seam - less embossing press to obtain Coating 1; Step S42: Aluminum wire is evaporated into vapor by an evaporation boat and adheres to the surface of Coating 1 to form an aluminum coating, thus obtaining the anti - counterfeiting film.

4. The preparation method of an anti - counterfeiting film with a color - changing effect according to claim 3, characterized in that, in Step S41, the embossing temperature range of the seam - less embossing press is 170 - 190 °C, and the embossing pressure range is 2.5 - 3.5 MPa; Step S42 is carried out in a vacuum chamber, and the heating temperature of the evaporation boat is 1400 - 1500 °C.

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