Preparation method and use of biomimetic hydrogel anti-counterfeiting label

Abstract

The application discloses a preparation method of a biomimetic hydrogel anti-counterfeiting label and application thereof. The biomimetic hydrogel anti-counterfeiting label comprises a substrate layer carrying encrypted information and an information carrier layer adhered thereto. The preparation method comprises the following steps: uniformly mixing monomer hydroxyethyl methacrylate, crosslinking agent ethylene glycol dimethacrylate and photoinitiator phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide to obtain solution A for preparing an anti-counterfeiting label precursor; dissolving ammonium molybdate hydrate (Mo7) into deionized water to obtain solution B for impregnation; transferring the A solution into a shaping mold, and after reaction and condensation into gel under ultraviolet light in the pattern area of a to-be-replicated piece substrate, the biomimetic hydrogel anti-counterfeiting label is obtained by impregnation in solution B; and then pattern generation is carried out under ultraviolet light to achieve the design of secondary encryption. The anti-counterfeiting label prepared by the application has high recognition degree, and due to the multi-layer encryption characteristics, the anti-counterfeiting safety is higher, and the encoding mode is simple and easy to operate. Only by doping one kind of element, the information encryption with a maximum encoding capacity of 10 10000 can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high polymer material preparation, in particular to a preparation method and application of a biomimetic hydrogel-based anti-counterfeiting label. BACKGROUND

[0002] Hydrogel is a functional polymer material with three-dimensional network structure formed by cross-linking of hydrophilic polymer chains in water. It is commonly used in medicine, agriculture and information fields. For information storage, wafer, glass chip and other materials have high technical barriers and expensive raw materials. Using hydrogel as a substitute can greatly reduce the production cost, and using light curing method for preparation can further reduce the requirement for preparation technology.

[0003] Physical anti-counterfeiting technology mainly refers to physical printing anti-counterfeiting technology. Special printing process and processing equipment are used to manufacture unique trace characteristics on printed products to achieve the purpose of anti-counterfeiting. Optical biomimetic information is often used for encryption. Existing methods often use plant templates, including lotus leaves, rose petals, rose leaves, ginkgo leaves, and velvet calathea leaves. Considering that feathers have a complex cascade lock system composed of flexible hooks, sliding rails and thorns at the end of the sliding rails as end structures. Due to its structural characteristics, the texture shape is different due to the difference in applied force, so the range of optical anti-counterfeiting templates can be expanded. At the same time, the present application is still suitable for the original anti-counterfeiting templates, such as leaves. SUMMARY

[0004] The purpose of the present application is to provide a preparation method of a biomimetic hydrogel anti-counterfeiting label.

[0005] The biomimetic hydrogel anti-counterfeiting label prepared by the present application contains two layers of anti-counterfeiting information, namely microtexture encryption information for primary anti-counterfeiting and optical selected area pattern information for secondary anti-counterfeiting.

[0006] The characteristic value of the microtexture encryption information for primary anti-counterfeiting is calculated by the Hamming distance calculation formula.

[0007] The optical selected area pattern information for secondary anti-counterfeiting is derived from the characteristic color of molybdenum ions in the structure.

[0008] The preparation method of the biomimetic hydrogel anti-counterfeiting label comprises the following steps:

[0009] S1, mixing and stirring monomers, cross-linking agents and photoinitiators to obtain solution A, wherein the monomers are hydroxyethyl methacrylate, the cross-linking agent is ethylene glycol dimethacrylate, and the photoinitiator is phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide;

[0010] S2, dissolving ammonium molybdate hydrate (Mo7) into deionized water to obtain solution B;

[0011] S3, transferring solution A obtained in S1 to the glass substrate area carrying the feather base, polymerizing and coagulating under ultraviolet light to form a first-level biomimetic anti-counterfeiting hydrogel label;

[0012] S4, selecting a film paper light template with a set pattern, and mapping secondary anti-counterfeiting information to the surface of the label prepared in step S3 by ultraviolet light irradiation to obtain a twice-encrypted biomimetic hydrogel anti-counterfeiting label. Preferably, the crosslinking agent content in step S1 is 0.4%-1% of the monomer molar content, and the content of the photoinitiator is 1.6-3.2% of the monomer molar content.

[0013] Preferably, in step S2, ammonium molybdate hydrate (Mo7) is dissolved into deionized water to obtain solution B, wherein the content of Mo7 is 50 mmol / L.

[0014] Preferably, in step S3, the polymerization and coagulation time is 5 min.

[0015] Preferably, in step S4, the ultraviolet light irradiation time is 6 min.

[0016] Compared with the prior art, the present application has the following beneficial effects: the present application first uses the feather micro-texture structure as anti-counterfeiting information, combined with biological encryption. The preparation process is simple and easy to operate, avoiding the cumbersome steps of repeated freezing and thawing required by the existing hydrogel anti-counterfeiting label. At the same time, the prepared anti-counterfeiting label has the characteristics of information writing, erasing, rewriting, and re-erasing, not only realizing the information burn after reading but also saving material resources. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Process diagram for preparing the anti-counterfeiting label of the present application.

[0018] Figure 2 Process diagram for preparing the anti-counterfeiting label and writing, erasing, and rewriting information thereof.

[0019] Figure 3 Flowchart for micro-texture characteristic value calculation and encrypted information identification.

[0020] Figure 4 Stress-strain contrast chart for different instances. DETAILED DESCRIPTION

[0021] The specific embodiments of the present application are further described below. It is to be understood that the embodiments described are illustrative of the principles of the present application and are not intended to limit the scope thereof. Further, the features of the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0022] The experimental methods in the following examples are all conventional methods unless otherwise specified. The experimental materials used in the following examples are all commercially available unless otherwise specified.

[0023] As Figure 1 The color conversion rule and color change mechanism provided by the pre-experiment can determine Figure 2 the information writing time and then the anti-fake label information writing. Referring to Figure 2 , the prepared anti-fake label contains secondary encryption information. They are primary micro-text encryption information and secondary optical selected pattern information, respectively. In the case of pre-delivering characteristic values to users, according to Figure 3 , the anti-fake label characteristic values are compared. If they are consistent, it means that the first decryption is passed and the image is identified. Otherwise, it is marked as a fake label.

[0024] To determine the light response time, the pre-experiment shown in Figure 1 was carried out. It can be found that the pre-prepared substrate began to change color under the irradiation of 254 nm ultraviolet light for 20 s, and the color change gradually deepened with the extension of time. In order to analyze the principle, XPS test was carried out, and the left upper and lower figures are the comparison before and after ultraviolet light irradiation. Among them, Mo(VI) absorption peaks are observed at binding energies of 232.49 eV and 235.69 eV. Mo(V) absorption peaks are observed at 231.79 eV and 234.99 eV. The valence state of molybdenum element is synthesized by Gaussian fitting method, and the black solid line is the fitting calculation result, which is consistent with the test value. The calculated spectrum is integrated to obtain the area of the calculated proportion of the two valence states. The Mo(V) / Mo ratio before ultraviolet irradiation is 25.48%. After ultraviolet irradiation, the binding energy of the gel changes, and the Mo(V) / Mo value increases significantly to 40.81%. Mo(VI) in the gel is photoreduced after ultraviolet irradiation, thereby producing photochromism.

[0025] Example 1

[0026] The present application provides a preparation method of a biomimetic hydrogel anti-fake label, referring to the preparation method of Figure 2 (a) comprising the following steps:

[0027] S1, mixing and stirring hydroxyethyl methacrylate, ethylene glycol dimethacrylate, phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide to obtain solution A, wherein the content of crosslinking agent is 1% of the monomer molar content, and the content of photoinitiator is 1.6% of the monomer molar content;

[0028] S2, dissolving ammonium molybdate hydrate (Mo7) into deionized water to obtain solution B, wherein the content of Mo7 is 50 mmol / L;

[0029] S3, transferring solution A mentioned in S1 to the glass substrate area carrying the feather base, and polymerizing and condensing into a primary biomimetic anti-counterfeiting hydrogel label under ultraviolet light, and the polymerization and condensation time is 5 min.

[0030] S4, after the primary biomimetic anti-counterfeiting hydrogel label is immersed in solution B, a film paper light template with a set pattern is selected to map secondary anti-counterfeiting information to the surface of the primary anti-counterfeiting label by ultraviolet irradiation to obtain a secondary encrypted biomimetic hydrogel anti-counterfeiting label, and the ultraviolet irradiation time is 6 min.

[0031] Referring to the preparation method of Figure 2 (b), the butterfly pattern is mapped onto the primary anti-counterfeiting label containing the micro-texture structure. The information retention time is observed. After being placed at room temperature for 18 h, the information is completely eliminated, and the imaging effect is not affected after remapping.

[0032] Referring to the preparation method of Figure 3 , the use steps of the anti-counterfeiting label are described. The manufacturer prepares the biomimetic hydrogel anti-counterfeiting label according to the preparation steps of Figure 2 , and calculates the characteristic values, and the results are a=0.1 and b=0.7. The characteristic values are further transmitted to the user. The user receives the characteristic values and the biomimetic hydrogel anti-counterfeiting label entity. The electronic device is used to check whether the characteristic values are consistent, and if they are consistent, the image characteristics are further identified to obtain the original image information. After the information disappears, the label can be reused.

[0033] Example 2

[0034] The present application provides a preparation method of a biomimetic hydrogel anti-counterfeiting label, referring to the preparation method of Figure 2 (a) comprising the following steps:

[0035] S1, mixing and stirring hydroxyethyl methacrylate, ethylene glycol dimethacrylate, phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide to obtain solution A, wherein the content of crosslinking agent is 1% of the monomer molar content, and the content of photoinitiator is 1.6% of the monomer molar content;

[0036] S2, ammonium molybdate hydrate (Mo7) is dissolved into deionized water to obtain solution B, wherein the Mo7 content is 50 mmol / L;

[0037] S3, solution A mentioned in S1 is transferred to the glass substrate area carrying the feather base and is polymerized and condensed under ultraviolet light to form a first-level biomimetic anti-counterfeiting hydrogel label, and the polymerization and condensation time is 5 min.

[0038] S4, after the first-level biomimetic anti-counterfeiting hydrogel label is immersed in solution B, a film paper light template with a set pattern is selected to map secondary anti-counterfeiting information to the surface of the first-level biomimetic anti-counterfeiting hydrogel label by ultraviolet light irradiation to obtain a twice-encrypted biomimetic hydrogel anti-counterfeiting label, and the ultraviolet light irradiation time is 6 min.

[0039] Example 3

[0040] The application provides a preparation method of a biomimetic hydrogel anti-counterfeiting label, referring to Figure 2 The preparation method of (a) comprises the following steps:

[0041] S1, hydroxyethyl methacrylate, ethylene glycol dimethacrylate and phenyl bis (2, 4, 6-trimethyl benzoyl) phosphine oxide are mixed and stirred uniformly to obtain solution A, wherein the content of the crosslinking agent is 1% of the monomer molar content, and the content of the photoinitiator is 3.2% of the monomer molar content;

[0042] S2, ammonium molybdate hydrate (Mo7) is dissolved into deionized water to obtain solution B, wherein the Mo7 content is 50 mmol / L;

[0043] S3, solution A mentioned in S1 is transferred to the glass substrate area carrying the feather base and is polymerized and condensed under ultraviolet light to form a first-level biomimetic anti-counterfeiting hydrogel label, and the polymerization and condensation time is 5 min.

[0044] S4, after the first-level biomimetic anti-counterfeiting hydrogel label is immersed in solution B, a film paper light template with a set pattern is selected to map secondary anti-counterfeiting information to the surface of the first-level biomimetic anti-counterfeiting hydrogel label by ultraviolet light irradiation to obtain a twice-encrypted biomimetic hydrogel anti-counterfeiting label, and the ultraviolet light irradiation time is 6 min.

[0045] Stress-strain tests are performed on the solution A solidification precursors in examples 1, 2 and 3 for different monomer ratios of the crosslinking agent, and the results are shown in Figure 4 , and the specific parameters of the test components are shown in the drawings.

[0046] Micro-texture characteristic value calculation and encrypted information identification are performed on examples 2 and 3 for different substrates, and the results are shown in Figure 3 .

[0047] The above examples are only used to illustrate the present application and not to limit the scope of the present application. The present application is not limited to the detailed description of the above embodiments. For those skilled in the art, various changes, modifications, replacements and variations of the embodiments can be made without departing from the principles and spirits of the present application, and still fall within the protection scope of the present application.

Claims

1. A biomimetic hydrogel-based anti-counterfeiting label, characterized in that, The anti-counterfeiting label comprises one or more transparent substrates, which contain a groove pattern for macrostructure shaping and a plane for carrying a base of a piece to be copied, for micro-bionic coding, and an encrypted pattern comprising two characteristic values is generated by template UV irradiation on the shaped surface to prepare a multi-layer encrypted label; Preparation is carried out by the following steps: S1, mixing and stirring monomers, crosslinking agents and photoinitiators to obtain solution A, wherein the monomers are hydroxyethyl methacrylate, the crosslinking agent is ethylene glycol dimethacrylate, and the photoinitiator is phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide; the content of the crosslinking agent is 0.4%-1% of the molar content of the monomers, and the content of the photoinitiator is 1.6%-3.2% of the molar content of the monomers; S2, dissolving ammonium molybdate hydrate (Mo7) into deionized water to obtain solution B; S3, transferring solution A obtained in S1 to the transparent substrate area carrying the piece to be copied, and polymerizing and condensing under UV light to form a primary bionic anti-counterfeiting hydrogel label; S4, immersing the primary bionic anti-counterfeiting hydrogel label in solution B, selecting a film paper template with a set pattern, and mapping secondary anti-counterfeiting information to the surface of the label prepared in step S3 by UV irradiation to obtain a twice-encrypted bionic hydrogel anti-counterfeiting label.

2. The biomimetic hydrogel-based anti-counterfeiting label according to claim 1, characterized in that, The anti-counterfeit label coding capacity formula is: coding capacity=M N Wherein M is the number of optical response signals generated by any point of the substrate layer, M=2, 10, N is the total number of all points in the substrate layer, N=10x10, 50x50, 100x100.

3. The biomimetic hydrogel-based anti-counterfeiting label according to claim 1, characterized in that, The primary anti-counterfeiting is the microstructure pattern of the piece to be copied, and the secondary anti-counterfeiting is the selected area encryption pattern obtained by UV mapping.

4. The biomimetic hydrogel-based anti-counterfeiting label according to claim 1, characterized in that, The transparent substrate is glass, PDMS or acrylic.

5. The biomimetic hydrogel-based anti-counterfeiting label according to claim 1, wherein The piece to be copied is selected from biological structures such as feathers and leaves with micro-texture characteristics.

6. The biomimetic hydrogel-based anti-counterfeiting label according to claim 1, wherein The characteristic values are Hamming inter-distance and Hamming intra-distance, respectively: The Hamming inter-distance calculation formula is a(x, y) = ∑x[i]⊕y[i], where i = 1,..n-1, x and y are n-bit encodings obtained by binary or decimal quantization of two different label scan images, and ⊕ represents XOR; The Hamming intra-distance calculation formula is b(x, y) = ∑x[i]⊕x[i+1], where i = 1,..n-1, and x[n] = x[1] is satisfied, x and y are n-bit encodings obtained by binary or decimal quantization of the label scan image, and ⊕ represents XOR.

7. The biomimetic hydrogel-based security tag according to any one of claims 1-6, wherein, The anti-counterfeiting label is scanned by an electronic device to verify the bionic microstructure, so as to be applied to reading and verifying identity information; Further, an encrypted image is presented under daily light.

8. The biomimetic hydrogel-based security tag according to any one of claims 1-6, wherein, The ciphertext information of the anti-counterfeiting label can be encrypted and destroyed.

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