CN2550776Y - Anti-fake mark - Google Patents

Abstract

An anti-counterfeit mark, an image layer is arranged on the viscose layer, and a plastic substrate is arranged on the image layer. A metal reflective layer may be disposed between the plastic substrate and the adhesive layer, and a spectrum transformation pattern layer with a relief structure is also disposed on the metal reflective layer. The anti-counterfeiting mark, which the inventor calls "spectral transformation anti-counterfeiting mark", is a practical technology researched and developed by the inventor to increase the anti-counterfeiting strength of the anti-counterfeiting mark, and is an anti-counterfeiting mark that hides information on the anti-counterfeiting mark. Since the hidden information is unreadable by human eyes, it is necessary to use machine recognition for detection, which increases the difficulty of forgery and improves the anti-counterfeiting strength.

Description

an anti-counterfeiting mark

technical field

The utility model belongs to the laser holographic anti-counterfeiting technology, in particular to an anti-counterfeiting mark.

Background technique

my country has started the development of laser embossed holographic technology since the mid-1980s (around 1987). Because laser holographic marks cannot be simply copied by ordinary photography and printing methods; and with the emergence of embossed holographic technology, low-cost mass production of holograms can be realized, so laser embossed holograms quickly gained a lot of attention in terms of anti-counterfeiting security. application. Optical technology is used for anti-counterfeiting, mainly by using the basic laws of scattering, reflection, transmission, absorption, and diffraction produced when light interacts with matter to obtain certain special visual effects, such as multi-layer optical medium film structure, grating structure, etc. .

At present, the main means of anti-counterfeiting in the field of optics are multi-layer dielectric film structure, grating structure and various types of optical holography technology using the concept of information optics using thin film interference effect. The efforts to increase the anti-counterfeiting strength by using the optical effects of various technical means on holographic marks are collectively referred to as DOVDs (Diffraction Optical Variable Devices) internationally, that is, optically variable components, which involve many unit technologies such as: Kinegram, Multiplane (2D/3D ), Object Oriented, DotOriented (Dot-Matrix hologram), Pixel Oriented and microlens technology, etc. The holographic types used for actual marking and packaging materials abroad include narrow-width molding, wide-width molding, molded metallized paper, molded hot stamping, self-adhesive photopolymer, photopolymer, wide-width molded composite film, and molded strips and embossed lines, demetallized or partially demetallized transparent film/hot stamping film, dichromated gelatin, silver halide, etc.; the image methods used are 2D/3D, dot matrix hologram, 3D, uniform repeating pattern (wallpaper type ), shallow (Shallow) 3D, combined holography (isotopy), diffraction grating, white light transmission, white light reflection, etc.

Over the past ten years, the domestic anti-counterfeiting holographic technology has also been deeply developed and applied. Domestic optical holographic anti-counterfeiting has adopted various technical means. For example, dynamic holographic technology, multi-channel technology, 2D/3D technology, dot matrix holographic technology, photochemical relief technology, micro-encryption technology and anti-copy technology are used on molded holographic carriers. DOVDs products. But generally speaking, the technology is not enough to keep improving, and there is still a gap between the equipment and process research used to realize these technical means and foreign countries. For example, foreign countries use Zero-order Grating Microstructure (zero-order grating microstructure) to make sub-micron gratings; research on Optical Thin-Film Security Devices (optical film security devices) uses media with various refractive indices The recognizable effect and anti-counterfeiting effect that can be obtained by Multilayer Coatings (multilayer coating) made of thin film; research on different process methods to make See-Through Hologram (transparent hologram); in order to improve the diffraction efficiency of paper hologram and adopt a new Plate making process, etc. Due to the successful application of laser holographic anti-counterfeiting technology, it has become the number one counterfeit target of counterfeiters, and they try their best to forge anti-counterfeiting holographic marks. Moreover, with the rapid popularization of molded holographic technology, the forgery technology of molded holographic anti-counterfeiting labels has also spread, thereby reducing the anti-counterfeiting performance of molded holographic labels. The emergence of counterfeit holograms not only confuses the public, but also disrupts the market, making the newly emerging anti-counterfeiting hologram industry also become victims together with the general public. In order to improve the anti-counterfeiting strength of laser holographic anti-counterfeiting technology, it is necessary to continuously improve the optical characteristics of laser hologram itself, and improve and realize new manufacturing processes.

In order to change the embarrassing situation that laser holographic anti-counterfeiting products are currently facing, it is necessary to intensify efforts in industry management and establish an access system for anti-counterfeiting product manufacturers and a registration system for anti-counterfeiting products. Laser holographic anti-counterfeiting technology itself also needs to speed up research on holographic plate-making, new materials (including substrates) and machine-reading technology for holographic anti-counterfeiting. For example, using computer digital holographic plate-making technology; developing paper-based materials suitable for paper holographic needs; developing various polymer materials required for holographic hot stamping technology; researching one-time-use special materials for laser holographic anti-counterfeiting marks; and so on.

Contents of the invention

The purpose of the utility model is to provide a new type of anti-counterfeiting mark, which is not easy to forge, and its anti-counterfeiting strength is greatly improved.

In order to achieve the purpose of the above utility model, an anti-counterfeit label is provided with an image layer on the adhesive layer and a plastic base on the image layer, characterized in that: the image layer is a spectrum transformation graphic layer with a relief structure.

A metal reflective layer may be arranged between the above-mentioned plastic substrate and the adhesive layer, and a spectrum conversion graphic layer with a relief structure is also arranged on the metal reflective layer.

The anti-counterfeiting mark is a practical technology researched and developed by the inventor to increase the anti-counterfeiting strength of the anti-counterfeiting mark. It is an anti-counterfeiting mark that hides information on the anti-counterfeiting mark. Since the hidden information is unreadable by human eyes, it is necessary to use machine recognition for detection, which increases the difficulty of forgery and improves the anti-counterfeiting strength.

Description of drawings

Fig. 1 is a structural schematic diagram of a reflective anti-counterfeiting mark;

Fig. 2 is a Fourier transform spectrogram;

Figure 3 is a schematic diagram of information reproduction during laser irradiation and reflection;

Fig. 4 is a schematic diagram of reproduction of information in the case of laser irradiation and transparency.

Detailed ways

As shown in Figure 1, reflective anti-counterfeiting marks can usually be composed of three layers of different materials. The first layer is a plastic substrate 1 (such as PET plastic), the second layer is a metal reflective layer 2 (such as metal aluminum foil), and the third layer is an adhesive layer 3, which is usually a pressure-sensitive adhesive, that is, a self-adhesive layer. The spectrum transformation pattern is embossed on the plastic substrate and the metal reflective layer in the form of a relief structure by a molding process to form a spectrum transformation pattern layer 4 .

The transmissive anti-counterfeiting label does not contain a metal reflective layer, and the spectral transformation graphics are embossed on the plastic substrate in the form of a relief structure.

The spectral transformation graph is introduced below.

Through the analysis of the diffraction light field by physical optics, we know that in the case of Fraunhofer diffraction (far-field diffraction ₎ , the light field u( _x , y) can be written as: $u(x,\mathrm{the\; y})=c\&Integral;\&Integral;0(x_0,{\mathrm{the\; y}}_0)\exp [-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="Y0227837600071.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;}(\mathrm{\&xi;}{x}_0+\mathrm{\&eta;}{\mathrm{the\; y}}_0)]d{x}_{0}d{\mathrm{the\; y}}_0---\left(1\right)$ Among them, x ₀ , y ₀ are object space coordinates; x, y are image space coordinates; c is a complex constant; the integration area is (-∞, +∞).

Equation (1) points out that the complex amplitude distribution of the Fraunhofer diffraction field is the Fourier transform of the complex amplitude of the diffracting object. In this way, the intensity Φ(x,y) of the diffraction field can be written as: Φ(x,y)=|u(x,y)| ² ＝(1/λ ² z ₀ ² |0(ξ,η)| ² (2) In the formula, $0(\mathrm{\&xi;},\mathrm{\&eta;})=\&Integral;\&Integral;0(x_0,{\mathrm{the\; y}}_0)\exp [-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="Y0227837600071.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;}(\mathrm{\&xi;}{x}_0+\mathrm{\&eta;}{\mathrm{the\; y}}_0)]d{x}_{0}d{\mathrm{the\; y}}_0---\left(3\right)$ 0(ξ, η) is the Fourier transform of 0(x ₀ , y ₀ ). Known by inverse transformation $0(x_0,{\mathrm{the\; y}}_0)=\&Integral;\&Integral;0(\mathrm{\&xi;},\mathrm{\&eta;})\exp \left[\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="Y0227837600071.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;}(\mathrm{\&xi;}{x}_0+\mathrm{\&eta;}{\mathrm{the\; y}}_0)\right]\mathrm{d\&xi;d\&eta;}---\left(4\right)$ Therefore, in the Fraunhofer diffraction field, the relationship between the diffracting object and the light distribution of the diffracting light field is reduced to a mathematical relationship of Fourier transform. This is an important basis for modern Fourier optics.

According to the above principle, some kind of information (text or pattern) is firstly transformed by Fourier to obtain the spectrogram shown in Fig. 2 . Then the Fourier transform spectrum in FIG. 2 is fabricated on the aluminized plastic film 7 in the form of a relief structure, such as 4 in FIG. 3 . When irradiating with laser light 6, after the reflection of aluminized plastic film 7, put a piece of white paper (or other planes that can be imaged) 5 on the optical path of reflected light, as shown in Figure 3, just can be in this See the original information (text or pattern) on the white paper. It is also possible to make the Fourier transform spectrogram 4 on the laser holographic mark in the form of a relief structure, and the original information can be displayed when the laser is reproduced.

If the Fourier transform spectrum is made on the transparent plastic film 8 in the form of a relief structure, the transmitted light when irradiated with laser light also reproduces the original information, as shown in FIG. 4 .

Since information that cannot be interpreted by human eyes is hidden in the spectral transformation anti-counterfeiting label, machine-readable technology (ie, machine recognition) can be used for detection. This provides an information hiding method for machine identification of anti-counterfeiting marks.

Claims (2)

1. an anti-counterfeiting mark is provided with image layer on adhesive-layer, is provided with plastic-substrates on image layer, it is characterized in that: described image layer is the spectral transformation graph layer of embossment structure.

2. anti-counterfeiting mark according to claim 1 is characterized in that: be provided with metallic reflector between described plastic-substrates and the adhesive-layer, also be provided with the spectral transformation graph layer of embossment structure on this metallic reflector.

Images