Anti-counterfeiting product and manufacturing method and application thereof

Abstract

The invention provides an anti-counterfeiting product and a manufacturing method and application thereof, the anti-counterfeiting product comprises a substrate with a target geometrical shape and a finger-shaped pattern formed on the substrate, and the anti-counterfeiting product comprises first authentication information, second authentication information and third authentication information, the first authentication information is different outline contours and sizes of the anti-counterfeiting product, the second authentication information is a crotch-shaped pattern formed by integrating a bifurcation point, a ridge and a tail end point of the ridge in the finger-shaped pattern, and the third authentication information is the size change of the finger-shaped pattern, including the width and / or height change of the finger-shaped structure. According to the invention, the finger-shaped pattern with the layered structure can be manufactured by utilizing the viscosity fingering instability, and the manufacturing method does not need to use a mold, is simple, convenient, expandable, economical and efficient, and has universality. The continuous tip splitting and size gradient endow the finger-shaped pattern with an unclonable characteristic, so that the finger-shaped pattern can be used for anti-counterfeiting of paper money and the like, the anti-counterfeiting means is simple and convenient, and the anti-counterfeiting efficiency is high.

Description

Technical Field

[0001] The invention relates to an anti-counterfeiting product and a manufacturing method and application thereof, belonging to the technical field of micro-pattern manufacturing and anti-counterfeiting. Background Art

[0002] The generation of micropatterned structures and micropatterned polymer surfaces is an emerging field with a wide range of applications from the manufacture of microchips and microelectromechanical devices to the preparation of cell growth and adhesion substrates. Such structures can usually be manufactured by common techniques such as molding (imprinting), microimprinting, soft lithography and laser scanning, but these common techniques require specialized instruments and cumbersome steps, which are time-consuming, error-prone, and costly. In addition, custom molds are mostly indispensable in these processes, further increasing their complexity and cost. In addition, some manufacturing routes are not suitable for generating patterns on polymer substrates.

[0003] Compared with the above complex techniques, the Hele-Shall apparatus (HSC) can also produce patterned surfaces based on the viscous fingering instability (VF) principle. This method does not require molds, is simple to operate, scalable and cost-effective. Specifically, finger-like patterns appear when a low-viscosity fluid invades a high-viscosity fluid sandwiched between two substrates of the HSC. The apparatus was first used by Saffman and Taylor in 1958 to conduct viscous fingering instability (VF) experiments. After years of development, a variety of HSCs with different geometries and properties have been developed to prepare various VF patterns. According to the basic geometry, HSCs used to study VF of two-phase flow can be divided into two categories: linear (channel) geometry and radial (circular) geometry. The former focuses on studying the mechanism of steady-state selection, such as using linear HSCs in the presence of an electric field or conical linear HSCs to study the transition between steady and unsteady states at the two-phase interface. On the other hand, radial HSCs focus on asymptotic morphology related to the concept of fractal growth. Daccord et al. fabricated fractal sticky fingers in a radial Hele-Shaw setup, allowing their study for the first time to be uncomplicated by boundary conditions such as those present in traditional linear elements.

[0004] In addition, some improved HSCs are generally considered to have different geometric structures, such as rotating HSCs and lifting HSCs. Among them, the lifting HSC is particularly special because it achieves the penetration of low-viscosity fluid into high-viscosity fluid by pulling apart two substrates containing high-viscosity fluids, rather than injecting low-viscosity fluids by continuously applying pressure. One of the substrates is fixed, and the other substrate is lifted in parallel or lifted by rotation around a fixed edge. After that, the less viscous fluid infiltrates the viscous fluid and forms a finger-like pattern. In particular, it can be used to make solid three-dimensional fractal patterns. Tanveer et al. proposed a strategy for making multi-scale fractal structures by rotating and lifting HSCs. The finger-like structures first penetrate from the pulling side and converge to a point close to the other end of the plate, where they encounter fingers from that end, resulting in an increasing trend in branch thickness and width from the starting point to the confluence.

[0005] However, even when using rectangular substrates, most published work on lift-off HSCs uses circular high-viscosity fluid films that do not cover the entire substrate, but only occupy a portion of the overlapping area of ​​the substrate, surrounded by a large amount of air. As the substrates separate, the surrounding air will invade the liquid film to form finger-like patterns, which eventually converge at the center of the liquid film, and their size tends to increase in the process.

[0006] As mentioned above, currently micropattern structures and micropattern polymer surfaces are mostly used in different fields such as the manufacture of microchips and microelectromechanical devices and the preparation of cell growth and adhesion substrates. Based on the excellent properties of micropattern structures and micropattern polymer surfaces, improving their production methods and expanding their application technology fields have become technical problems that need to be urgently solved in this field. Summary of the invention

[0007] In order to solve the above-mentioned shortcomings and deficiencies, the purpose of the present invention is to provide an anti-counterfeiting product and a manufacturing method and application thereof.

[0008] In order to achieve the above objectives, the present invention provides an anti-counterfeiting product, wherein the anti-counterfeiting product includes a substrate with a target geometric shape and a finger-shaped pattern formed on the substrate, and the anti-counterfeiting product includes first authentication information, second authentication information and third authentication information, wherein the first authentication information is different outer contours and sizes of the anti-counterfeiting product, the second authentication information is a tree-like pattern formed by integrating bifurcation points, ridges and end points of ridges in the finger-shaped pattern, and the third authentication information is the size change of the finger-shaped pattern, including changes in the width and / or height of the finger-like structure.

[0009] As a specific implementation of the anti-counterfeiting product described above in the present invention, the shape of the substrate includes a square, a hexagon, a triangle, a circle, a pentagon or a hexagon.

[0010] As a specific implementation of the anti-counterfeiting product described above in the present invention, the finger-shaped pattern has a 3D hierarchical structure, that is, a three-dimensional pattern structure with a hierarchical structure.

[0011] On the other hand, the present invention also provides a method for making the anti-counterfeiting product described above, wherein the method comprises:

[0012] Selecting a substrate having a target geometric shape to obtain an anti-counterfeiting product with different outer contours, and extracting the different outer contours of the anti-counterfeiting product as first authentication information;

[0013] forming a finger-shaped pattern on the substrate, determining bifurcation points, ridges and ridge end points according to the finger-shaped pattern, integrating the bifurcation points, ridges and ridge end points to form a tree-shaped pattern, and extracting the tree-shaped pattern as second authentication information;

[0014] At the same time, the size change of the finger-shaped pattern, including the change of the width and / or height of the finger-shaped structure, is extracted and used as the third authentication information to complete the production of the anti-counterfeiting product.

[0015] As a specific embodiment of the above-mentioned manufacturing method of the present invention, a finger-shaped pattern is formed on the substrate using a rotary lifting HSC device, wherein the device comprises the substrate and a rotatable plate, one end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force so that the angle θ (the value range is 0°<θ<1°) between the substrate and the rotatable plate changes continuously, and forming the finger-shaped pattern on the substrate comprises:

[0016] sandwiching a certain amount of high-viscosity fluid between the substrate and the rotatable plate, and forming an initial liquid film to cover the entire overlapping area between the substrate and the rotatable plate;

[0017] The rotatable plate is rotated to make the low-viscosity fluid invade the initial liquid film from the non-fixed end to form an advancing interface, and viscous fingering instability occurs on the advancing interface to form a finger-shaped pattern.

[0018] The present invention does not specifically require the method of rotating the rotatable plate, and any method that can rotate and separate the rotatable plate from the substrate, such as a pump and a motor, can be used in the present invention. As a specific embodiment of the above-mentioned manufacturing method of the present invention, a syringe pump can be used to rotate the rotatable plate, and the speed of the pump only affects the speed of plate separation, and has no effect on the spatial distribution of the pattern finally formed.

[0019] In the rotary lifting HSC device used in the present invention, the rotatable plate can rotate along the fixed end under the action of external force so that the angle θ (the value range is 0°<θ<1°) between the substrate and the rotatable plate changes continuously, thereby the length of the experimental area can be flexibly selected by adjusting the size of the overlapping area between the substrate and the rotatable plate.

[0020] As a specific implementation of the above-mentioned manufacturing method of the present invention, the time for forming the finger-shaped pattern is less than or equal to 5 seconds.

[0021] As a specific embodiment of the above-mentioned manufacturing method of the present invention, any material that can present a fluid state and can be solidified can be used as the high-viscosity fluid in the present invention. In order to achieve the maximum viscosity contrast, the low-viscosity fluid includes air, water or low-viscosity oil, and the high-viscosity fluid includes a polymer, nanoparticles and / or nanofibers, such as silicon dioxide nanoparticles, titanium dioxide nanoparticles, silver nanowires, ferromagnetic nanoparticles, nanoalumina particles, nanocellulose or ceramic nanofibers, and mixtures thereof dissolved or dispersed in a volatile solvent to obtain a fluid, a photocurable resin (such as ETPTA, etc.), a thermosetting elastomer (such as PDMS, etc.) or a phase change material (such as paraffin, etc.), etc.

[0022] The present invention does not make specific requirements on the volatile solvent, and a reasonable selection can be made according to actual operation needs. For example, in some embodiments of the present invention, the volatile solvent can be toluene or the like.

[0023] As a specific implementation of the above application of the present invention, the high-viscosity fluid includes polyurethane adhesive, toluene solution of polystyrene or paraffin, etc.

[0024] As a specific embodiment of the above application of the present invention, the viscosity of the polyurethane adhesive is 2500-4000 mPa·s, the mass fraction of the polystyrene toluene solution is 20-30%, and the melting point of paraffin is 58-60° C. In some embodiments of the present invention, the viscosity of the silicone oil can be, for example, 200 mPa·s, 500 mPa·s, and 750 mPa·s.

[0025] As a specific embodiment of the manufacturing method described above, the substrate and the rotatable plate are made of the same or different materials, and the materials can be common basic materials such as glass or acrylic. In some embodiments of the present invention, the surface of the substrate can be subjected to various engineering treatments, such as modifying the hydrophilicity and hydrophobicity of the surface or drawing lines and patterns on the surface. For example, drawing lines and patterns on the surface can guide the advancement of the gas-liquid interface to obtain a structure with a corresponding pattern, such as Figure 4a-4d shown.

[0026] As a specific embodiment of the above-mentioned manufacturing method of the present invention, the size of the finger-shaped pattern is continuously reduced along the intrusion direction, wherein the size includes a characteristic width, i.e., the width of the finger-shaped pattern before it is about to bifurcate and / or the height of the fingers in the finger-shaped pattern. In the present invention, air invades the initial liquid film from the non-fixed end to form a finger-shaped pattern, and then extends forward to the fixed end. In this process, since the initial liquid film covers the entire overlapping area between the substrate and the rotatable plate, the finger-shaped pattern has an increasingly faster speed from the beginning to the end, resulting in its size becoming smaller and smaller (i.e., the finger width and / or height both show a downward trend), and its minimum size can reach about fifteen microns, which is rare. In addition, the initial liquid film covers the entire overlapping area between the substrate and the rotatable plate, and a finger-shaped pattern with a larger area can also be obtained.

[0027] As a specific implementation of the above-mentioned manufacturing method of the present invention, the real-time liquid film thickness corresponding to the real-time position of the advancing interface at different times satisfies:

[0028] h=h0+1000α(Lx), where h is the real-time liquid film thickness in μm, α is the radian angle of θ, θ is the angle between the substrate and the rotatable plate, and its value range is 0°<θ<1°, h0 is the initial liquid film thickness in the range of 5-15 μm, L is the length of the substrate in mm, and x is the real-time position of the advancing interface at different times, that is, the length of the real-time position from the non-fixed end in mm.

[0029] As a specific embodiment of the above-mentioned manufacturing method of the present invention, the characteristic width of the finger-shaped pattern, that is, the width of the finger before bifurcation, satisfies:

[0030] W / h is inversely proportional to Ca, where W is the characteristic width of the finger-like pattern, h is the real-time liquid film thickness, Ca = 12μv / γ is the capillary number, where γ is the interfacial tension between the high-viscosity fluid and the low-viscosity fluid, μ is the viscosity of the high-viscosity fluid, and v refers to the local velocity of a single finger tip.

[0031] In another aspect, the present invention also provides the use of the anti-counterfeiting product in the anti-counterfeiting of banknotes, passports, anti-tampering labels, securities, stamps, identity cards or textiles, etc. During the application, anti-counterfeiting is performed by combining the first authentication information, the second authentication information and the third authentication information of the anti-counterfeiting product.

[0032] In summary, the present invention can utilize viscous fingering instability to manufacture finger-like patterns with hierarchical structures, and the manufacturing method thereof does not require the use of molds, is simple in process, scalable, cost-effective and versatile; in addition, the manufacturing process is carried out at room temperature, which avoids the consumption of additional energy and deformation caused by heating (e.g., in hot pressing). Operation at room temperature is suitable for the processing of a variety of materials, which greatly expands the range of available materials compared with other manufacturing methods. In particular, the manufactured finger-like pattern is a three-dimensional hierarchical structure, and the width and / or height of the fingers tend to decrease from the beginning to the end. The continuous tip splitting and size gradient give the finger-like pattern the characteristic of being non-cloneable, making it easy to manufacture but difficult to copy, which means that the finger-like pattern can show significant variability, so that it can be used for anti-counterfeiting of banknotes, passports, anti-tamper labels, securities, stamps, identity cards or textiles, etc., and the anti-counterfeiting means are simple and the anti-counterfeiting efficiency is high. In addition, the present invention can also prepare a finger-like pattern structure with multiple functions by using an engineered substrate and a high-viscosity fluid with specific functions (e.g., a polymer solution, a nanoparticle suspension, and a combination thereof, etc.), which is helpful in many applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1a Schematic diagram of the structure of the rotary lifting HSC device used in the embodiment of the present invention.

[0035] Figure 1b The finger-shaped pattern (3 mm) formed by using silicone oil as the defense fluid in Example 1 of the present invention was recorded by a high-speed camera (Fastcam Mini, Photron) at a frame rate of up to 4000 f.ps.

[0036] Figure 1c This is a real-life picture (5 mm) of the finger-shaped pattern formed by using a toluene solution of polystyrene as the defense fluid in Example 1 of the present invention, recorded by an ordinary camera.

[0037] Figure 1d The minimum size of the finger-like pattern (20 μm) formed by using the polyurethane adhesive as the defense fluid in Example 1 of the present invention was recorded using a microscope.

[0038] Figure 1eThis is a scanning electron microscope image (200 μm) of the starting end of the finger-shaped pattern made using polyurethane adhesive as the defense fluid in Example 1 of the present invention.

[0039] Figure 1f This is a scanning electron microscope image (200 μm) of the end of the finger-shaped pattern made using polyurethane adhesive as the defense fluid in Example 1 of the present invention.

[0040] Figure 1g This is an optical profilometer result diagram of the starting and ending ends of the finger-shaped pattern produced using a toluene solution of polystyrene as the defense fluid in Example 1 of the present invention.

[0041] Figure 2a This is a graph showing the relationship between the finger-shaped pattern structure and time in Example 2 of the present invention (2 mm).

[0042] Figure 2b This is a graph showing the relationship between the real-time position of the liquid film and time under different pump speed conditions in Example 2 of the present invention.

[0043] Figure 2c Graph showing the relationship between the bifurcation number N and t under different pump speed conditions in Example 2 of the present invention.

[0044] Figure 2d The characteristic width W in Embodiment 2 of the present invention is defined as the width of the finger-like structure before bifurcation.

[0045] Figure 2e Graph showing the relationship between W and N under different pump speed conditions in Example 2 of the present invention.

[0046] Figure 2f Graph showing the relationship between W and t under different pump speed conditions in Example 2 of the present invention.

[0047] Figure 2g Graph showing the relationship between W / h and Ca under different pump speed conditions in Example 2 of the present invention.

[0048] Figure 2h 4 is a graph showing the relationship between the rotation angle θ of the rotatable plate and the time t under different pump speed conditions in Example 2 of the present invention.

[0049] Figure 2i Graph showing the relationship between the velocity v and t of the finger-like structure under different pump speed conditions in Example 2 of the present invention.

[0050] Figure 2j Graph showing the relationship between the liquid film thickness h and t under different pump speed conditions in Example 2 of the present invention.

[0051] Figure 3a This is a diagram showing the relationship between the fractal dimension and time under different pump speed conditions in Example 3 of the present invention.

[0052] Figure 3b Graph showing the relationship between fractal dimension and time under different initial liquid film thickness conditions in Example 3 of the present invention.

[0053] Figure 3c This is a graph showing the relationship between fractal dimension and time under different silicone oil viscosities in Example 3 of the present invention.

[0054] Figure 3d This is a schematic diagram of selecting regions of the same size at the starting end and the end of the solid structure in Example 3 of the present invention, respectively recorded as Region 1 and Region 2 (scale bar is 3 mm).

[0055] Figure 3e is the d of region 1 and region 2 calculated in Example 3 of the present invention f Result graph. Figure 3a-3c and Figure 3e The values ​​in the table are the averages of 3 data.

[0056] Figure 4a-4d Schematic diagram of various finger-shaped pattern structures (scale: 5 mm) designed on an acrylic plate as a substrate in an embodiment of the present invention.

[0057] Figure 4e The finger-shaped pattern is prepared by using melted paraffin as the high-viscosity fluid in the embodiment of the present invention (the scale bar is 5 mm).

[0058] Figure 4f The finger-shaped pattern structure is obtained by enlarging the size of the substrate in an embodiment of the present invention.

[0059] Figure 5a Schematic diagram of the structure of the anti-counterfeiting product (scale is 5mm).

[0060] Figure 5b This is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 1 of the present invention (scale is 5 mm).

[0061] Figure 5c This is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 1 of the present invention (scale is 5 mm).

[0062] Figure 5d This is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 1 of the present invention (scale is 5 mm).

[0063] Figure 5e This is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 1 of the present invention (scale is 5 mm).

[0064] Figure 5fThis is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 1 of the present invention (scale is 5 mm).

[0065] Figure 5g This is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 2 of the present invention (the scale is 5 mm).

[0066] Figure 5h This is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 3 of the present invention (scale is 5 mm).

[0067] Figure 5i This is a schematic structural diagram of the anti-counterfeiting product provided in Application Example 4 of the present invention (scale is 5 mm).

[0068] Figure 6a This is a schematic structural diagram of the anti-counterfeiting product 1 provided in Application Example 5 of the present invention (the scale is 5 mm).

[0069] Figure 6b This is a schematic structural diagram of the anti-counterfeiting product 2 provided in Application Example 5 of the present invention (the scale is 5 mm).

[0070] Figure 6c This is a schematic structural diagram of the anti-counterfeiting product 3 provided in Application Example 5 of the present invention (the scale is 5 mm).

[0071] Figure 6d This is a schematic diagram obtained after extracting the authentication information of the anti-counterfeit product 1 in Application Example 5 of the present invention.

[0072] Figure 6e This is a schematic diagram obtained after extracting the authentication information of the anti-counterfeit product 2 in Application Example 5 of the present invention.

[0073] Figure 6f This is a schematic diagram obtained after extracting the authentication information of the anti-counterfeit product 3 in Application Example 5 of the present invention.

[0074] Figure 6g This is a result diagram obtained by integrating the first authentication information, the second authentication information and the third authentication information of anti-counterfeit products 1 to 3 in Application Example 5 of the present invention. DETAILED DESCRIPTION

[0075] It should be noted that the term "comprises" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0076] "Scope" disclosed in the present invention is given in the form of lower limit and upper limit. It can be one or more lower limits, and one or more upper limits respectively. A given range is defined by selecting a lower limit and an upper limit. The selected lower limit and upper limit define the boundaries of a particular range. All ranges defined in this way are combinable, i.e. any lower limit can be combined with any upper limit to form a range. For example, for a specific parameter, a range of 60-120 and 80-110 is listed, and it is understood that a range of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​listed are 1 and 2, and the maximum range values ​​listed are 3, 4 and 5, then the following ranges can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5.

[0077] In the present invention, unless otherwise specified, the numerical range "ab" represents an abbreviation of any real number combination between a and b, where a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" have been listed in the present invention, and "0-5" is just an abbreviation of these numerical combinations.

[0078] In the present invention, unless otherwise specified, all embodiments and preferred embodiments mentioned in the present invention can be combined with each other to form a new technical solution.

[0079] In the present invention, unless otherwise specified, all technical features and preferred features mentioned in the present invention can be combined with each other to form a new technical solution.

[0080] In the present invention, if not specifically stated, the term "two" used in this specification means "at least two".

[0081] In the present invention, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0082] In the present invention, unless otherwise specified, "first", "second" and "third" do not indicate a sequence of precedence or limit the materials, steps or information, but are only used to distinguish that they are not the same material, step or information. For example, "first", "second" and "third" in "first authentication information", "second authentication information" and "third authentication information" are only used to indicate that they are not the same authentication information.

[0083] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and Examples. The following described embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention. If the specific conditions are not specified in the embodiments, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0084] Example 1

[0085] In this embodiment, air is used as the low-viscosity fluid and silicone oil (purchased from Aladdin) is used as the high-viscosity fluid. Figure 1a The rotary lifting HSC device of the structure shown forms a finger-shaped pattern on the substrate. The device includes the substrate and a rotatable plate, both of which are ordinary glass slides with a size of 76.2×25.4 mm. One end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force to make the angle θ (the value range is 0°<θ<1°) between the substrate and the rotatable plate continuously change. The finger-shaped pattern is formed on the substrate including:

[0086] The rotary lift HSC device is placed horizontally, the substrate is fixed, a certain amount of silicone oil with a viscosity of 500 mPa·s is placed on the substrate, and then a rotatable plate is used to squeeze the silicone oil to fill / cover the entire overlap area between the substrate and the rotatable plate, and a delay of about 30 seconds is made for the silicone oil to stabilize, forming a thin initial liquid film with a thickness of 10 μm;

[0087] The rotatable plate is rotated to allow air to invade the initial liquid film from the non-fixed end to form an advancing interface, on which viscous fingering instability occurs to form a dense finger-like pattern.

[0088] Figure 1bThe finger-like pattern formed by silicone oil as the defensive fluid was recorded by a high-speed camera (Fastcam Mini, Photron) at a frame rate of up to 4000f.ps, which shows the evolution of the finger-like pattern from Figure 1b It can be seen that the dense finger-like pattern has an obvious size gradient from beginning to end.

[0089] However, due to the liquid properties of silicone oil, the finger-shaped pattern prepared above is unlikely to continue to exist after the experiment. Therefore, in order to maintain the integrity of the manufactured finger-shaped pattern, this embodiment also uses toluene as a solvent to prepare a toluene solution of polystyrene with a mass fraction of 25%, and uses it as a defense fluid, that is, a high-viscosity fluid, and uses air as an intrusion fluid, that is, a low-viscosity fluid, and uses the above-mentioned device and method to prepare the finger-shaped pattern; because the toluene solution of polystyrene is used as the defense fluid, the manufactured structure can be "frozen" when the toluene evaporates, that is, a solid structure is obtained, as shown in the actual picture. Figure 1c As shown, from Figure 1c It can be seen that the width of the finger-like pattern changes significantly, and the color change reveals the height change of the finger-like pattern. The darker the color, the higher the height. This shows that the change in the width and height of the finger-like structure can be used as the third authentication information for anti-counterfeiting. Of course, only the change in the width or the change in the height of the finger-like structure can be used as the third authentication information for anti-counterfeiting as needed. In addition, this embodiment also uses polyurethane adhesive (with a viscosity of 3200mPa·s) as the defense fluid to study the minimum size of the finger-like pattern that can be prepared, such as Figure 1d As shown, its minimum size can reach about fifteen microns.

[0090] Figure 1e and Figure 1f The scanning electron micrographs (200 μm) show the start and end of the finger-shaped pattern made with polyurethane adhesive as the defensive fluid. Figure 1e and Figure 1f As can be seen in Figure 1, the scanning electron microscopy results of the starting and ending of the finger-like pattern also show a surprising size contrast. In addition, the optical surface profilometer results of the starting and ending of the finger-like pattern prepared with a toluene solution of polystyrene are shown in Figure 1. Figure 1g As shown, Figure 1g It shows that there is also a size difference between the two structures in height. In short, the finger-like pattern structure prepared by this method is a 3D hierarchical structure.

[0091] Example 2

[0092] In this embodiment, air is used as the low-viscosity fluid, and silicone oil (purchased from Aladdin, with a viscosity of 500 mPa·s) is used as the high-viscosity fluid. Figure 1aThe rotary lifting HSC device of the structure shown forms a finger-shaped pattern on the substrate. The device includes the substrate and a rotatable plate, both of which are ordinary glass slides with a size of 76.2×25.4 mm. One end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force to make the angle θ (the value range is 0°<θ<1°) between the substrate and the rotatable plate continuously change. The finger-shaped pattern is formed on the substrate including:

[0093] The rotary lift HSC device is placed horizontally, the substrate is fixed, a certain amount of silicone oil is placed on the substrate, and then the silicone oil is squeezed using a rotatable plate to fill / cover the entire overlap area between the substrate and the rotatable plate, and a delay of about 30 seconds is made for the silicone oil to stabilize, forming a thin initial liquid film with a thickness of 12 μm;

[0094] The rotatable plate is rotated by a syringe pump (Syringe Pump LSP01-1A) to allow air to invade the initial liquid film from the non-fixed end to form a forward interface, on which viscous fingering instability occurs to form a dense finger-like pattern.

[0095] In order to explore the characteristics of the finger-like pattern structure during the development process, this embodiment examines the relationship between the change of the finger-like pattern structure over time under the condition of a pump speed of 0.80 mm / s. Figure 2a As shown. Figure 2a As can be seen in the figure, with the intrusion of air, finger-like structures appear. In the early stage, the growth of the finger is lateral expansion and axial extension. When one end of the finger exceeds the adjacent finger, the lateral expansion will cause the growth of the adjacent finger to be inhibited. After the finger is fully developed, its growth is mainly axial extension. Throughout the development process, the structure continues to evolve through the gradual bifurcation of the fingertips.

[0096] In order to quantify the growth of the pattern, this embodiment also uses a syringe pump (Syringe Pump LSP01-1A) to drive the rotating rotatable plate at different pump speeds to prepare a finger-like pattern structure, where G1, G2 and G3 represent the different pump speeds used in the three groups of experiments, which are 0.32, 0.48 and 0.80 mm / s, respectively.

[0097] On this basis, this embodiment first studies the motion law of the rotatable plate, such as Figure 2h As shown, from Figure 2h It can be seen that the rotation angle θ and time t present a quadratic function relationship, the relationship is θ = at 2 , where a is 0.03649, 0.07434 and 0.17058 for G1, G2 and G3 respectively. In addition, the real-time position of the liquid film can be observed from the side. The relationship between the real-time position of the liquid film and time in the side view under different pump speed conditions is shown in the figure Figure 2b As shown. Figure 2b It can be seen that the fingers grow slowly at a nearly constant speed at the beginning. At this stage, the fingers not only grow forward, but also grow sideways. In the later stage, the fingers tend to grow forward rapidly. It is worth noting that the continuous growth of the fingers is achieved through bifurcation. Figure 2c The relationship between the number of bifurcations, N, and t is shown. As the fingers develop, the rate of bifurcations increases.

[0098] In order to study the size change of the pattern, the present invention defines the characteristic width W as the width of the finger before bifurcation (such as Figure 2d ). First, measure W and N, and the relationship between them is as follows Figure 2e By mapping W to N at the Nth bifurcation, two stages can be observed. Throughout the process, W shows a decreasing trend with the increase of N, and W has a faster decreasing trend in the later stage, which is attributed to the incomplete development of early fingers. The behavior of fingers at this stage is similar to Figure 2b behavior in. Figure 2f Describing the change of W with t, it can be seen that W shows a downward trend with the increase of t. Figure 2e and Figure 2f The experimental results in demonstrate that the prepared structures have significant differences in width.

[0099] In addition, the present invention defines the capillary number Ca=12μv / γ, where γ is the interfacial tension between the high-viscosity fluid and the low-viscosity fluid, μ is the viscosity of the high-viscosity fluid, and v refers to the local velocity of the tip of a single finger. Among them, v is time-dependent, and it shows a constant upward trend and increases sharply at the end (such as Figure 2i Then, the behavior of W normalized by h is studied (as shown in Figure 2g As shown), the results in the figure show that W / h is inversely proportional to Ca. Figure 2j It shows that h and t have a cubic function relationship, the relationship is h = at 3 +bt 2 +ct+d, where for G1, G2, and G3, a are -2.41169, -6.38191, and -23.42436, b are 7.35799, 19.07853, and 45.30847, c are 11.45648, 12.70316, and 26.25613, and d are 11.40013, 12.87501, and 13.74244, respectively.

[0100] Example 3

[0101] In order to quantify the global characteristics of the pattern, this example conducted a series of experiments using silicone oil as a high-viscosity fluid and calculated the fractal dimension d of the resulting pattern using a method called box counting dimension. f. Use boxes of size l to cover the pattern. The number of boxes used to completely cover the pattern is n. Then we can get n~l df , then d f =log(n) / log(l). The analyzed area is taken from the end of the real-time pattern.

[0102] In this embodiment, silicone oil (purchased from Aladdin, with a viscosity of 500 mPa·s) is used as a high-viscosity fluid, and the method in reference to Example 2 is used as follows: Figure 1a The rotary lift HSC device of the structure shown rotates the rotatable plate at different pump speeds to form finger-like patterns on the substrate, where G1, G2 and G3 represent the different pump speeds used in the three groups of experiments, which are 0.32, 0.48 and 0.80 mm / s, respectively. The relationship between the fractal dimension and time under different pump speed conditions is investigated, as shown in Figure 3a As shown, for different pump speeds (0.32, 0.48 and 0.80 mm / s), d f In the early stage, it gradually increases with the growth of t. Later, d f tends to be stable, but the difference is that higher pump speed corresponds to faster equilibrium.

[0103] In this embodiment, silicone oil (purchased from Aladdin, with a viscosity of 500 mPa·s) is used as a high-viscosity fluid, and the method in Reference Example 2 is used as follows: Figure 1a The rotary lift HSC device with the structure shown rotates the rotatable plate at a pump speed of 0.8 mm / s to form a finger-like pattern on the substrate, and the relationship between the fractal dimension and time under different initial liquid film thicknesses (8, 9, 10 and 11 μm, respectively) is investigated. Figure 3b shown.

[0104] This example also uses silicone oils of different viscosities (purchased from Aladdin, with viscosities of 200, 500 and 750 mPa·s, respectively) as high-viscosity fluids, and uses the method in reference to Example 2. Figure 1a The rotary lift HSC device with the structure shown rotates the rotatable plate at a pump speed of 0.8 mm / s to form a finger-like pattern on the substrate, and the relationship between the fractal dimension and time under different silicone oil viscosities is investigated under the condition that the initial liquid film thickness is 10 μm, as shown in Figure 3c shown.

[0105] Figure 3b and Figure 3c Showing Figure 3a Similar trend, i.e. d f This can be explained by the self-similar properties of fully developed fingers, which exhibit approximately constant d fIn addition, regions of the same size were selected at the beginning and end of the solid structure formed with a toluene solution of polystyrene as the defense fluid, respectively, such as Figure 3d As shown, and measure its d f , the measured d f The results are as follows Figure 3e As shown. Figure 3e It can be seen that the starting end d f is lower than the end, which is similar to Figure 3a-3c The results for the liquid structures shown are consistent and are all below 2.

[0106] In summary, the above shows the results of fabricating hierarchical structures with a minimum size of about fifteen microns by viscous fingering instability without a mold. The thin liquid film is sandwiched between two parallel substrates. By rotating one of the substrates, the surrounding air invades the liquid film to form an advancing air-liquid interface, on which viscous fingering instability occurs to produce a finger-like pattern. The finger-like pattern has characteristics such as hierarchical structure and dimensions spanning multiple orders of magnitude. It is worth noting that it is achieved by continuous tip bifurcation of the fingers and increasingly faster forward speeds, resulting in increasingly smaller finger widths. The development process can be divided into two stages: early (immature development) and late (full development). In the early stage, the growth of the fingers is lateral expansion and axial extension, resulting in low forward speed and low bifurcation frequency. Correspondingly, the finger size is also relatively large. After the fingers are fully developed, their growth behavior is mainly axial extension, and the bifurcation frequency and forward speed increase, resulting in increasingly smaller finger sizes. In addition, the fingers also exhibit self-similar properties at this stage.

[0107] In addition, the properties of the fabricated hierarchical structures depend largely on the boundary conditions of the two substrates, such as substrate materials, substrate dimensions, and surface properties, etc. According to these boundary conditions, various structures can be obtained by designing the surface properties of the substrates. Figure 4a-4d As shown, an acrylic plate is used as a substrate and various patterns, such as straight lines or curves, are processed and engraved on the substrate and applied to prepare a layered structure. The high viscosity fluid used in preparing the layered structure is silicone oil with a viscosity of 500 mPa·s. Figure 4a-4d As can be seen in the figure, these patterns can guide the gas-liquid interface to advance along them to obtain a hierarchical structure with a preset pattern. In addition, the proposed fabrication technique is simple, scalable, and compatible with a variety of materials. In addition to preparing solid structures by solvent evaporation using easily solidified polymer materials such as polystyrene as described above, it can also be produced by controlling the temperature to transform the molten material into a solid state. Figure 4e The use of melted paraffin as a high-viscosity fluid to prepare finger-shaped patterns is demonstrated. In addition to the above two strategies, it is believed that other methods, such as UV curing, can also be used to prepare solid structures. Scalability is an important indicator of mass production and practical application capabilities. Figure 4fIt can be seen that even if the substrate area is enlarged several times (15×15 cm), a hierarchical structure with obvious size differences can still be obtained when the layered structure is prepared with a polystyrene toluene solution with a mass concentration of 25% as the high viscosity fluid, which proves its scalability and lays a solid foundation for its application.

[0108] Application Example 1

[0109] This application embodiment provides a series of anti-counterfeiting products, which are made by a production method comprising the following specific steps:

[0110] Select four identical square substrates, made of acrylic and with a size of 10×10 mm, to respectively obtain anti-counterfeiting products with square outlines, and extract the square outlines of the anti-counterfeiting products as the first authentication information;

[0111] The finger-shaped patterns are formed on the substrates respectively by using a rotary lift HSC device, wherein the device comprises the substrate and a rotatable plate (made of glass with a size of 76.2×25.4 mm), one end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force, and the finger-shaped patterns are formed on the substrate including:

[0112] sandwiching different amounts of high-viscosity fluid (polystyrene-toluene solution with a mass fraction of 25%) between the substrate and the rotatable plate, and forming an initial liquid film to cover the entire overlapping area between the substrate and the rotatable plate;

[0113] The rotatable plate is rotated at different rotation speeds respectively, so that the low-viscosity fluid invades the initial liquid film from the non-fixed end to form an advancing interface, and viscous fingering instability occurs on the advancing interface to form a finger-like pattern, and the bifurcation point, the ridge and the end point of the ridge are determined according to the finger-like pattern, and then the bifurcation point, the ridge and the end point of the ridge are integrated to form a tree-like pattern, and the tree-like pattern is extracted as the second authentication information. In addition, the distance between two adjacent ridges can be used as the width of the finger-like pattern, which shows a decreasing trend along its development direction, and is extracted as the third authentication information to complete the production of the anti-counterfeiting product, respectively as follows Figure 5b-5f As shown, Figure 5e and Figure 5f Corresponding to the same anti-counterfeiting product, both are used to display the first authentication information, the second authentication information and the third authentication information of the anti-counterfeiting product.

[0114] Among them, the series of anti-counterfeiting products include a square substrate and a finger-shaped pattern formed on the substrate. The first authentication information in the series of anti-counterfeiting products is the square outline of the anti-counterfeiting product. The second authentication information is a tree-like pattern formed by integrating the bifurcation points, ridges and end points of the ridges in the finger-shaped pattern. The third authentication information is the size change of the finger-shaped pattern, specifically the change in the width of the finger-shaped structure, that is, the width of each finger-shaped pattern shows a decreasing trend along its development direction.

[0115] Application Example 2

[0116] This application embodiment provides an anti-counterfeiting product, which is made by a manufacturing method including the following specific steps:

[0117] A five-pointed star-shaped substrate is selected, the material of which is acrylic, and the side length of the five-pointed star is 5.5 mm, so as to obtain an anti-counterfeiting product with a five-pointed star-shaped outline, and the five-pointed star outline of the anti-counterfeiting product is extracted as the first authentication information;

[0118] The finger-shaped pattern is formed on the substrate by using a rotary lift HSC device, wherein the device comprises the substrate and a rotatable plate (made of glass with a size of 76.2×25.4 mm), one end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force, and the finger-shaped pattern is formed on the substrate. The device comprises:

[0119] A certain amount of high viscosity fluid (polystyrene-toluene solution with a mass fraction of 25%) is sandwiched between the substrate and the rotatable plate, and the formed initial liquid film covers the entire overlapping area between the substrate and the rotatable plate;

[0120] The rotatable plate is rotated to allow the low-viscosity fluid to invade the initial liquid film from the non-fixed end to form an advancing interface, on which viscous fingering instability occurs to form a finger-like pattern, and the bifurcation points, ridges and ridge end points are determined according to the finger-like pattern, and then the bifurcation points, ridges and ridge end points are integrated to form a tree-like pattern, and the tree-like pattern is extracted as the second authentication information. In addition, the distance between two adjacent ridges can be used as the width of the finger-like pattern, which shows a decreasing trend along its development direction, and is extracted as the third authentication information to complete the production of the anti-counterfeiting product, such as Figure 5g shown.

[0121] Among them, the anti-counterfeiting product includes a five-pointed star-shaped substrate and a finger-shaped pattern formed on the substrate, the first authentication information in the anti-counterfeiting product is the five-pointed star outline of the anti-counterfeiting product, the second authentication information is a tree-branched pattern formed by integrating the bifurcation points, ridges and end points of the ridges in the finger-shaped pattern, and the third authentication information is the size change of the finger-shaped pattern, specifically the change in the width of the finger-shaped structure, that is, the width of each finger-shaped pattern shows a decreasing trend along its development direction.

[0122] Application Example 3

[0123] This application embodiment provides an anti-counterfeiting product, which is made by a manufacturing method including the following specific steps:

[0124] A hexagonal substrate is selected, the material of which is acrylic, and the diagonal distance and the distance between the opposite sides of the hexagon are both 15 mm, so as to obtain an anti-counterfeiting product with a hexagonal outer contour, and the hexagonal outer contour of the anti-counterfeiting product is extracted as the first authentication information;

[0125] The finger-shaped pattern is formed on the substrate by using a rotary lift HSC device, wherein the device comprises the substrate and a rotatable plate (made of glass with a size of 76.2×25.4 mm), one end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force, and the finger-shaped pattern is formed on the substrate. The device comprises:

[0126] A certain amount of high viscosity fluid (polystyrene-toluene solution with a mass fraction of 25%) is sandwiched between the substrate and the rotatable plate, and the formed initial liquid film covers the entire overlapping area between the substrate and the rotatable plate;

[0127] The rotatable plate is rotated to allow the low-viscosity fluid to invade the initial liquid film from the non-fixed end to form an advancing interface, on which viscous fingering instability occurs to form a finger-like pattern, and the bifurcation points, ridges and ridge end points are determined according to the finger-like pattern, and then the bifurcation points, ridges and ridge end points are integrated to form a tree-like pattern, and the tree-like pattern is extracted as the second authentication information. In addition, the distance between two adjacent ridges can be used as the width of the finger-like pattern, which shows a decreasing trend along its development direction, and is extracted as the third authentication information to complete the production of the anti-counterfeiting product, such as Figure 5h shown.

[0128] Among them, the anti-counterfeiting product includes a hexagonal substrate and a finger-shaped pattern formed on the substrate, the first authentication information in the anti-counterfeiting product is the hexagonal outline of the anti-counterfeiting product, and the second authentication information is a tree-like pattern formed by integrating the bifurcation points, ridges and end points of the ridges in the finger-shaped pattern, and the third authentication information is the size change of the finger-shaped pattern, specifically the change in the width of the finger-shaped structure, that is, the width of each finger-shaped pattern shows a decreasing trend along its development direction.

[0129] Application Example 4

[0130] This application embodiment provides an anti-counterfeiting product, which is made by a manufacturing method including the following specific steps:

[0131] A circular substrate is selected, the material of which is acrylic and the diameter is 15 mm, so as to obtain an anti-counterfeiting product with a circular outer contour, and the circular outer contour of the anti-counterfeiting product is extracted as the first authentication information;

[0132] The finger-shaped pattern is formed on the substrate by using a rotary lift HSC device, wherein the device comprises the substrate and a rotatable plate (made of glass with a size of 76.2×25.4 mm), one end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force, and the finger-shaped pattern is formed on the substrate. The device comprises:

[0133] A certain amount of high viscosity fluid (polystyrene-toluene solution with a mass fraction of 25%) is sandwiched between the substrate and the rotatable plate, and the formed initial liquid film covers the entire overlapping area between the substrate and the rotatable plate;

[0134] The rotatable plate is rotated to allow the low-viscosity fluid to invade the initial liquid film from the non-fixed end to form an advancing interface, on which viscous fingering instability occurs to form a finger-like pattern, and the bifurcation points, ridges and ridge end points are determined according to the finger-like pattern, and then the bifurcation points, ridges and ridge end points are integrated to form a tree-like pattern, and the tree-like pattern is extracted as the second authentication information. In addition, the distance between two adjacent ridges can be used as the width of the finger-like pattern, which shows a decreasing trend along its development direction, and is extracted as the third authentication information to complete the production of the anti-counterfeiting product, such as Figure 5i shown.

[0135] Among them, the anti-counterfeiting product includes a circular substrate and a finger-shaped pattern formed on the substrate, the first authentication information in the anti-counterfeiting product is the circular outline of the anti-counterfeiting product, and the second authentication information is a tree-like pattern formed by integrating the bifurcation points, ridges and end points of the ridges in the finger-shaped pattern, and the third authentication information is the size change of the finger-shaped pattern, specifically the change in the width of the finger-shaped structure, that is, the width of each finger-shaped pattern shows a decreasing trend along its development direction.

[0136] like Figure 5a-Figure 5i As shown, the dots represent the end points and bifurcation points of the ridges, while the lines are the ridges. Integrating the bifurcation points, ridges, and end points of the ridges in the finger-like pattern reveals a specific tree-branching pattern that has a one-to-one correspondence with the anti-counterfeiting product, a feature that is very helpful in anti-counterfeiting.

[0137] Now the original anti-counterfeiting products stored in the database, such as Figure 5a The anti-counterfeiting products provided in the examples 1 to 4 are used as examples to illustrate the application of the anti-counterfeiting products in the anti-counterfeiting of banknotes, passports, anti-tampering labels, securities, stamps, identity cards or textiles. For example, the original anti-counterfeiting products are used for the anti-counterfeiting of banknotes, passports, anti-tampering labels, securities, stamps, identity cards or textiles. Figure 5a As shown, the first authentication information, the second authentication information and the third authentication information of the original anti-counterfeiting product are all known information. When decoding, first apply the information in Example 1 as shown in FIG. Figure 5b-5f The anti-counterfeiting products shown in the figure and the anti-counterfeiting products provided in application examples 2 to 4 are respectively similar in shape, profile and size to those in the embodiment 1. Figure 5a By comparing the outline and size of the anti-counterfeiting product shown in the figure, the mismatched samples can be screened out in a short time, that is, the anti-counterfeiting products provided in Application Example 2 to Application Example 4, and then the anti-counterfeiting products in Application Example 1 Figure 5b-5f The tree-branch pattern of the anti-counterfeiting product shown is Figure 5a The tree-branch pattern of the anti-counterfeiting product shown in the figure is compared with the Figure 5e The outline and dimensions of the display and Figure 5f The size variation of the tree-like and finger-like patterns shown is similar to Figure 5a The authentication information of the anti-counterfeiting products shown can be completely matched, so the authenticity can be determined.

[0138] In summary, the present invention needs to ensure that the size changes of the outer contour, the tree-branch pattern and the finger-shaped pattern meet the requirements at the same time in order to achieve the decoding of the anti-counterfeit product and determine it to be authentic.

[0139] Application Example 5

[0140] In order to verify that the anti-counterfeiting product provided by the present invention is non-clonable, this application example prepared three anti-counterfeiting products under the same experimental conditions and studied their similarities, including:

[0141] Three anti-counterfeiting products were prepared using a circular substrate (15 mm in diameter) and a 25% by mass polystyrene-toluene solution as a high viscosity fluid (with an initial liquid film thickness of 9 μm), respectively denoted as anti-counterfeiting product 1 to anti-counterfeiting product 3. Figure 6a-6c As shown;

[0142] Extract the first authentication information, the second authentication information and the third authentication information of the three anti-counterfeiting products respectively, such as Figure 6d-6f As shown;

[0143] The first authentication information, second authentication information, and third authentication information of the three anti-counterfeiting products obtained after extraction are integrated into one graph to study their similarities, such as Figure 6g As shown. Figure 6g It can be seen that the tree-like structures of the three anti-counterfeiting products show obvious differences, proving their differences. In summary, even the structures prepared under the same experimental conditions show obvious differences, proving its non-cloning nature.

[0144] The above is only a specific embodiment of the present invention, and cannot be used to limit the scope of the invention. Therefore, the replacement of equivalent components, or equivalent changes and modifications made according to the protection scope of the patent of the present invention, should still fall within the scope of this patent. In addition, the technical features of the present invention can be freely combined with each other, with each other and with each other, and with each other.

Claims

1. An anti-counterfeiting product, characterized in that: The anti-counterfeiting product includes a substrate with a target geometric shape and a finger-shaped pattern formed on the substrate, and the anti-counterfeiting product includes first authentication information, second authentication information and third authentication information, wherein the first authentication information is different outer contours and sizes of the anti-counterfeiting product, the second authentication information is a tree-like pattern formed by integrating bifurcation points, ridges and end points of ridges in the finger-shaped pattern, and the third authentication information is the size change of the finger-shaped pattern, including changes in the width and / or height of the finger-shaped structure.

2. The anti-counterfeiting product according to claim 1, characterized in that: The shape of the substrate includes square, hexagon, triangle, circle, pentagon or hexagon.

3. The anti-counterfeiting product according to claim 1 or 2, characterized in that: The finger-like pattern has a 3D hierarchical structure.

4. The method for producing an anti-counterfeit product according to any one of claims 1 to 3, characterized in that: The production method comprises: Selecting a substrate having a target geometric shape to obtain an anti-counterfeiting product with different outer contours, and extracting the different outer contours of the anti-counterfeiting product as first authentication information; forming a finger-shaped pattern on the substrate, determining bifurcation points, ridges and ridge end points according to the finger-shaped pattern, integrating the bifurcation points, ridges and ridge end points to form a tree-shaped pattern, and extracting the tree-shaped pattern as second authentication information; At the same time, the size change of the finger-shaped pattern, including the change of the width and / or height of the finger-shaped structure, is extracted and used as the third authentication information to complete the production of the anti-counterfeiting product.

5. The manufacturing method according to claim 4, characterized in that: The finger-shaped pattern is formed on the substrate by using a rotary lift HSC device, the device comprising the substrate and a rotatable plate, one end of the substrate and the rotatable plate are fixed together to form a fixed end, and the rotatable plate can rotate along the fixed end under the action of an external force, and the finger-shaped pattern is formed on the substrate. The device comprises: sandwiching a certain amount of high-viscosity fluid between the substrate and the rotatable plate, and forming an initial liquid film to cover the entire overlapping area between the substrate and the rotatable plate; The rotatable plate is rotated to make the low-viscosity fluid invade the initial liquid film from the non-fixed end to form an advancing interface, and viscous fingering instability occurs on the advancing interface to form a finger-shaped pattern.

6. The method according to claim 5, characterized in that: The low-viscosity fluid includes air, water or low-viscosity oil, and the high-viscosity fluid includes a fluid obtained by dissolving or dispersing a polymer, nanoparticles and / or nanofibers and a mixture thereof in a volatile solvent, a photocurable resin, a thermosetting elastomer or a phase change material.

7. The manufacturing method according to claim 6, characterized in that: The high-viscosity fluid includes a toluene solution of polystyrene, a polyurethane adhesive or paraffin.

8. The manufacturing method according to claim 5, characterized in that: The substrate and the rotatable plate are made of the same or different materials, and the materials are glass or acrylic.

9. The production method according to any one of claims 4 to 8, characterized in that: The size of the finger-shaped pattern decreases continuously along the intrusion direction, wherein the size includes a characteristic width, ie, the width of the finger-shaped pattern before it is bifurcated and / or the height of the fingers in the finger-shaped pattern.

10. The production method according to any one of claims 4 to 8, characterized in that: The real-time liquid film thickness corresponding to the real-time position of the advancing interface at different times satisfies: h=h0+1000α(Lx), where h is the real-time liquid film thickness in μm, α is the radian angle of θ, θ is the angle between the substrate and the rotatable plate, and its value range is 0°<θ<1°, h0 is the initial liquid film thickness in the range of 5-15 μm, L is the length of the substrate in mm, and x is the real-time position of the advancing interface at different times in mm.

11. The production method according to any one of claims 4 to 8, characterized in that: The characteristic width of the finger-like pattern, i.e. the width of the finger before bifurcation, satisfies: W / h is inversely proportional to Ca, where W is the characteristic width of the finger-like pattern, h is the real-time liquid film thickness, Ca = 12μv / γ is the capillary number, where γ is the interfacial tension between the high-viscosity fluid and the low-viscosity fluid, μ is the viscosity of the high-viscosity fluid, and v refers to the local velocity of a single finger tip.

12. Use of the anti-counterfeiting product according to any one of claims 1 to 3 in the anti-counterfeiting of banknotes, passports, anti-tamper labels, securities, stamps, identity cards or textiles.

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