阅读说明：本技术 点光源识读激光加密全息防伪垫片及其制备方法 (Point light source recognition laser encryption holographic anti-counterfeiting gasket and preparation method thereof ) 是由 张传东 张钦永 田兴坡 田辰琪 金凯 巩建宝 于 2020-06-12 设计创作，主要内容包括：本发明属于防伪技术领域,具体涉及一种点光源识读激光加密全息防伪垫片及其制备方法。所述的激光加密全息防伪垫片,包括从上到下上依次相连的PET层、成像层、激光加密信息层、镀铝层、印刷层、上胶黏剂层、发泡层、下胶黏剂层和下PET层,所述的激光加密信息层里面隐藏数字编码信息。本发明通过光栅晶格中的光栅空频以及光栅角度两个参量,制作激光加密信息层模压版,将激光加密信息复制在PET成像层上面,形成激光加密信息层,消费者使用手持式点光源设备照射全息防伪垫片的正面时,就会呈现隐藏信息,判断产品真伪,是一种难以仿制但易识别的新型全息防伪垫片。(The invention belongs to the technical field of anti-counterfeiting, and particularly relates to a point light source reading laser encryption holographic anti-counterfeiting gasket and a preparation method thereof. The laser encrypted holographic anti-counterfeiting gasket comprises a PET (polyethylene terephthalate) layer, an imaging layer, a laser encrypted information layer, an aluminum coating layer, a printing layer, a gluing agent layer, a foaming layer, a lower gluing agent layer and a lower PET layer which are sequentially connected from top to bottom, wherein digital coding information is hidden in the laser encrypted information layer. According to the invention, the laser encryption information layer mould pressing plate is manufactured through two parameters of the grating space frequency and the grating angle in the grating lattice, the laser encryption information is copied on the PET imaging layer to form the laser encryption information layer, when a consumer irradiates the front surface of the holographic anti-counterfeiting gasket by using the handheld point light source equipment, hidden information can be presented, and the authenticity of the product can be judged, so that the holographic anti-counterfeiting gasket is a novel holographic anti-counterfeiting gasket which is difficult to imitate but easy to identify.)

1. A pointolite recognition laser encryption holographic anti-fake gasket which characterized in that: the multifunctional laser encryption device comprises an upper PET layer (1), an imaging layer (2), a laser encryption information layer (3), an aluminum coating layer (4), a printing layer (5), an upper adhesive layer (6), a foaming layer (7), a lower adhesive layer (8) and a lower PET layer (9) which are sequentially connected from top to bottom, wherein digital coding information is hidden in the laser encryption information layer (3).

2. The point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 1, characterized in that: the thickness of the upper PET layer (1) and the lower PET layer (9) is 12-50 μm.

3. The point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 1, characterized in that: the thickness of the aluminum-plated layer (4) is

4. The point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 1, characterized in that: the upper adhesive layer (6) and the lower adhesive layer (8) are both food-grade adhesives.

5. The point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 1, characterized in that: the foaming layer (7) is made of PE foaming material, and the thickness is 0.5-3 mm.

6. The point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 1, characterized in that: the hidden digital coding information pattern in the laser encryption information layer (3) is one or more than one of characters, letters, numbers, symbols or figures.

7. The point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 1, characterized in that: the hidden digital coding information in the laser encryption information layer (3) is composed of a plurality of square grating lattice arrays, the processing mode is laser etching, and the grating lattices contain two parameters of grating space frequency and grating angle.

8. The preparation method of the point light source reading laser encryption holographic anti-counterfeiting gasket of any one of claims 1 to 7 is characterized by comprising the following steps: the method comprises the following steps:

(1) coating an imaging layer on the corona surface of the PET film, wherein the imaging layer cannot be separated from the PET;

(2) manufacturing a laser encrypted information layer mould pressing plate:

firstly, manufacturing a hidden pattern, placing the hidden pattern in a polar coordinate system, randomly extracting N (N is N x N) pixel points according to a system sampling method, wherein N is more than or equal to 4, respectively calculating the distance rho between each pixel point and the zero point of the coordinate system and the included angle theta, obtaining an N x N matrix according to the distance between each pixel point and the zero point of the coordinate system, and finally obtaining an empty-frequency gray-scale map matrix G; obtaining an n x n matrix according to an included angle between each pixel point and a zero point of a coordinate system, finally obtaining an angle gray-scale map matrix H, and completing plate making work of a laser encryption information layer mould pressing layer in a photoetching machine according to a space frequency gray-scale map matrix G and the angle gray-scale map matrix H to obtain a laser encryption information layer mould pressing plate;

(3) copying the laser encryption information on the mould pressing plate to the PET imaging layer by using a mould pressing and gravure printing integrated machine to form a laser encryption information layer;

(4) aluminizing the laser encrypted information layer by adopting a vacuum aluminizing method;

(5) washing off the aluminum layer in the gravure ink washing area by using an aluminum washing machine;

(6) printing anti-counterfeiting features on the aluminum washing area to form a printing layer;

(7) coating an adhesive layer on the surface of the printing layer and compounding the adhesive layer with a foaming layer;

(8) coating an adhesive layer on the other surface of the foaming layer to be compounded with the PET film,

(9) and die-cutting into single holographic gasket by using a die-cutting machine to obtain the holographic gasket.

9. The method for preparing the point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 8, which is characterized in that: the imaging layer in the step (1) is prepared from the following raw materials in parts by weight: 30-70 parts of resin FL-7103B, 0.03-0.07 part of assistant A1, 0.3-0.7 part of assistant B1, 0.5-2 parts of butyl ester and 1-3 parts of ethyl ester; the coating anilox roller is 100-300 meshes, and the wet coating amount is as follows: 4-8g/m²。

10. The method for preparing the point light source reading laser encryption holographic anti-counterfeiting gasket according to claim 8, which is characterized in that: the manufacturing method of the laser encryption information layer mould pressing plate comprises the following steps:

(1) according to the design file, making a hidden pattern, establishing a polar coordinate system, and placing the pattern at a zero point in the polar coordinate system;

(2) the resolution of the pattern is a b, the pattern is composed of a b pixel points, N (N is N) pixel points are randomly extracted according to a system sampling method, wherein N is more than or equal to 4, and a computer is used for calculating the coordinate value (x) of each pixel point₁，y₁)、(x₂，y₂)、(x₃，y₃)、……(x_N，y_N) And the distance (p) of each pixel point from the zero point₁、ρ₂、ρ₃、……ρ_N)；

(3) According to the polar coordinate system formula, x is rho cos theta, and y is rho cos theta, respectivelyCalculating the included angle (theta) between each pixel point and the zero point₁、θ₁、θ₁、……θ_N)；

(4) L is an observation distance and is a fixed parameter, β is a grating angle, d is a grating pitch, λ is a laser wavelength, β can be obtained according to tan β ═ ρ/L, and a grating pitch d can be obtained according to a grating equation sin β ═ λ/d, at which time a two-dimensional parameter (d) for each grating lattice can be established (d is a fixed parameter)₁，θ₁)、(d₂，θ₂)、(d₃，θ₃)……(d_N，θ_N)；

(5) From the grating pitch d of the N grating lattices, a matrix can be obtained as follows:

d₁，d₂，……………………d_n

d_n+1，d_n+2，………………d_2*n

………………………………

d_n*(n-1)+1，d_n*(n-1)+2，……d_n*n

calculating to obtain the maximum value d of d_maxAnd a minimum value d_minThe minimum value corresponds to a gray value of 0 and the maximum value corresponds to a gray value of 255, and according to the corresponding relationship, the values of N d can be mapped to another matrix G composed of gray values, and the matrix G constitutes a gray map as follows:

G₁，G₂，……………………G_n

G_n+1，G_n+2，………………G_2*n

………………………………

G_n*(n-1)+1，G_n*(n-1)+2，……G_n*n；

(6) from the angles θ of the N grating lattices, a matrix can be obtained as follows:

θ₁，θ₂，……………………θ_n

θ_n+1，θ_n+2，………………θ_2*n

………………………………

θ_n*(n-1)+1，θ_n*(n-1)+2，……θ_n*n

calculating to obtain the maximum value theta of theta_maxAnd minimum value theta_minThe minimum value corresponds to a gray value of 0 and the maximum value corresponds to a gray value of 255, and according to the corresponding relationship, the values of N θ can be mapped to another matrix H composed of gray values, and the matrix constitutes a gray map as follows:

H₁，H₂，……………………H_n

H_n+1，H_n+2，………………H_2*n

………………………………

H_n*(n-1)+1，H_n*(n-1)+2，……H_n*n；

(7) manufacturing an exposure unit according to the photoetching space frequency gray matrix G and the grating angle gray matrix H, wherein the size of the exposure unit is a square with the side length of n/R mm, R is the resolution of a photoetching image, and R is more than 10dpi and less than 50800 dpi;

(8) and (4) forming the exposure unit array in the step (7) into a designed size, manufacturing the exposure unit array on a photoetching offset plate through a photoetching process, and developing and electroplating to obtain the laser encryption information layer mould pressing plate.

Technical Field

The invention belongs to the technical field of anti-counterfeiting, and particularly relates to a point light source reading laser encryption holographic anti-counterfeiting gasket and a preparation method thereof.

Background

The traditional anti-counterfeiting gasket mainly has a sealing effect to prevent the product from being affected with damp, so that the product can be more effectively stored for a long time; and the product is well preserved in the transportation process, the bottle body does not scratch the bottle cap, and water in the bottle does not leak out. However, the competition of the sales markets of wine, beverages, health products and the like is increasingly violent, products of many manufacturers, especially famous brand products face huge counterfeit risks, and great cost is invested in anti-counterfeiting traceability.

The introduction of laser die stamping holographic anti-counterfeiting technology into China is that hundreds of production lines are introduced all over the country in the late 80 s and early 90 s, especially in the period from 1990 to 1994, and account for more than half of the world manufacturers at that time. In the early stage of introduction, the anti-counterfeiting technology indeed plays a certain anti-counterfeiting role, but as time goes on, the laser holographic image making technology is rapidly diffused, so that counterfeiters have broken through from various aspects nowadays, the anti-counterfeiting capability is almost completely lost, and people have to seek to improve the prior art. Therefore, optical image coding encryption technologies such as laser reading, optical micro-lithography, low-frequency lithography, random interference fringes and moire fringes are adopted, all the technologies need professional detection equipment to identify the authenticity, so that many consumers cannot use the anti-counterfeiting characteristics to identify the authenticity, and the market popularization is not facilitated.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the invention overcomes the defects of the prior art, provides a point light source recognizing laser encrypted holographic anti-counterfeiting gasket, which comprises a hidden digital coding information grating structure, and when a consumer uses a handheld point light source device to irradiate the front surface of the holographic anti-counterfeiting gasket, hidden information can be presented to judge whether the product is true or false.

The point light source reading laser encryption holographic anti-counterfeiting gasket comprises an upper PET layer, an imaging layer, a laser encryption information layer, an aluminum coated layer, a printing layer, an upper adhesive layer, a foaming layer, a lower adhesive layer and a lower PET layer which are sequentially connected from top to bottom, wherein digital coding information is hidden in the laser encryption information layer.

The thickness of the upper PET layer and the lower PET layer is 12-50 μm.

The thickness of the aluminum plating layer is

The upper adhesive layer and the lower adhesive layer are both food-grade adhesives.

The foaming layer is made of PE foaming material and has the thickness of 0.5-3 mm.

The hidden digital coding information pattern in the laser encryption information layer is one or more than one of characters, letters, numbers, symbols or figures.

The hidden digital coding information in the laser encryption information layer is composed of a plurality of square grating lattice arrays, the processing mode is laser etching, and the grating lattices contain two parameters of grating space frequency and grating angle.

The invention relates to a preparation method of a point light source reading laser encryption holographic anti-counterfeiting gasket, which comprises the following steps:

(1) coating an imaging layer on the corona surface of the PET film, wherein the imaging layer cannot be separated from the PET;

(2) manufacturing a laser encrypted information layer mould pressing plate:

firstly, manufacturing a hidden pattern, placing the hidden pattern in a polar coordinate system, randomly extracting N (N is N x N) pixel points according to a system sampling method, wherein N is more than or equal to 4, respectively calculating the distance rho between each pixel point and the zero point of the coordinate system and the included angle theta, obtaining an N x N matrix according to the distance between each pixel point and the zero point of the coordinate system, and finally obtaining an empty-frequency gray-scale map matrix G; obtaining an n x n matrix according to an included angle between each pixel point and a zero point of a coordinate system, finally obtaining an angle gray-scale map matrix H, and completing plate making work of a laser encryption information layer mould pressing layer in a photoetching machine according to a space frequency gray-scale map matrix G and the angle gray-scale map matrix H to obtain a laser encryption information layer mould pressing plate;

(3) copying the laser encryption information on the mould pressing plate to the PET imaging layer by using a mould pressing and gravure printing integrated machine to form a laser encryption information layer; the mould pressing temperature is 150-: 40-80 ℃;

(4) aluminizing the laser encrypted information layer by adopting a vacuum aluminizing method;

(5) washing off the aluminum layer in the gravure water ink washing area by using an aluminum washing machine, wherein the drying temperature is 60-80 ℃;

(6) printing anti-counterfeiting characteristics such as pictures and texts, two-dimensional codes and the like in the aluminum washing area to form a printing layer;

(7) coating an adhesive layer on the surface of the printing layer and compounding the adhesive layer with a foaming layer;

(8) coating an adhesive layer on the other surface of the foaming layer to be compounded with the PET film,

(9) and die-cutting into single holographic gasket by using a die-cutting machine to obtain the holographic gasket.

The adhesive is prepared from the following raw materials in parts by weight: 0.5-2 parts of resin 3160B, 6-10 parts of ethyl acetate and 3-7 parts of resin 3160A.

The imaging layer in the step (1) is prepared from the following raw materials in parts by weight: 30-70 parts of resin FL-7103B, 0.03-0.07 part of assistant A1, 0.3-0.7 part of assistant B1, 0.5-2 parts of butyl ester and 1-3 parts of ethyl ester; the coating anilox roller is 100-300 meshes, and the wet coating amount is as follows: 4-8g/m²。

The manufacturing method of the laser encryption information layer mould pressing plate comprises the following steps:

(1) according to the design file, making a hidden pattern, establishing a polar coordinate system, and placing the pattern at a zero point in the polar coordinate system;

(2) the resolution of the pattern is a b, the pattern is composed of a b pixel points, N (N is N) pixel points are randomly extracted according to a system sampling method, wherein N is more than or equal to 4, and a computer is used for calculating the coordinate value (x) of each pixel point₁，y₁)、(x₂，y₂)、(x₃，y₃)、……(x_N，y_N) And the distance (p) of each pixel point from the zero point₁、ρ₂、ρ₃、……ρ_N)；

(3) Calculating the included angle (theta) between each pixel point and the zero point according to the polar coordinate system formula x ═ rho cos theta and y ═ rho cos theta₁、θ₁、θ₁、……θ_N)；

(4) L is an observation distance and is a fixed parameter, β is a grating angle, d is a grating pitch, λ is a laser wavelength, β can be obtained according to tan β ═ ρ/L, and a grating pitch d can be obtained according to a grating equation sin β ═ λ/d, at which time a two-dimensional parameter (d) for each grating lattice can be established (d is a fixed parameter)₁，θ₁)、(d₂，θ₂)、(d₃，θ₃)……(d_N，θ_N)；

(5) From the grating pitch d of the N grating lattices, a matrix can be obtained as follows:

d₁，d₂，……………………d_n

d_n+1，d_n+2，………………d_2*n

………………………………

d_n*(n-1)+1，d_n*(n-1)+2，……d_n*n

calculating to obtain the maximum value d of d_maxAnd a minimum value d_minThe minimum value corresponds to a gray value of 0 and the maximum value corresponds to a gray value of 255, and according to the corresponding relationship, the values of N d can be mapped to another matrix G composed of gray values, and the matrix G constitutes a gray map as follows:

G₁，G₂，……………………G_n

G_n+1，G_n+2，………………G_2*n

………………………………

G_n*(n-1)+1，G_n*(n-1)+2，……G_n*n；

(6) from the angles θ of the N grating lattices, a matrix can be obtained as follows:

θ₁，θ₂，……………………θ_n

θ_n+1，θ_n+2，………………θ_2*n

………………………………

θ_n*(n-1)+1，θ_n*(n-1)+2，……θ_n*n

calculating to obtain the maximum value theta of theta_maxAnd minimum value theta_minThe minimum value corresponds to a gray value of 0 and the maximum value corresponds to a gray value of 255, and according to the corresponding relationship, the values of N θ can be mapped to another matrix H composed of gray values, and the matrix constitutes a gray map as follows:

H₁，H₂，……………………H_n

H_n+1，H_n+2，………………H_2*n

………………………………

H_n*(n-1)+1，H_n*(n-1)+2，……H_n*n；

(7) manufacturing an exposure unit according to the photoetching space frequency gray matrix G and the grating angle gray matrix H, wherein the size of the exposure unit is a square with the side length of n/R mm, R is the resolution of a photoetching image, and R is more than 10dpi and less than 50800 dpi;

(8) and (4) forming the exposure unit array in the step (7) into a designed size, manufacturing the exposure unit array on a photoetching offset plate through a photoetching process, and developing and electroplating to obtain the laser encryption information layer mould pressing plate.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention realizes a new anti-counterfeiting characteristic through a mathematical algorithm.

2. The invention is convenient for consumers to inquire the authenticity.

3. The invention is a new anti-fake characteristic, which makes the holographic anti-fake gasket have exclusivity.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a hidden pattern in embodiment 1 of the present invention;

FIG. 3 is a gray scale diagram corresponding to the matrix G in embodiment 1 of the present invention;

fig. 4 is a grayscale diagram corresponding to the matrix H in embodiment 1 of the present invention;

in the figure: 1. an upper PET layer; 2. an imaging layer; 3. a laser encrypted information layer; 4. plating an aluminum layer; 5. printing layer; 6. applying an adhesive layer; 7. a foamed layer; 8. a lower adhesive layer; 9. a lower PET layer.

Detailed Description

The invention is further described below with reference to the accompanying drawings and examples.