KR102214523B1 - Film structure for preventing counterfeit - Google Patents

Abstract

The present invention relates to an anti-counterfeiting film structure, which comprises: a base; and a composite image element provided on the base, having a diffraction pattern and provided to implement an image for first authenticity determination using light in a visible wavelength, and capable of selectively responding to a specific wavelength to implement an image for second authenticity determination. Thereby, images for composite authenticity determination can be implemented.

Description

Film structure for anti-counterfeiting {FILM STRUCTURE FOR PREVENTING COUNTERFEIT}

The present invention relates to an anti-counterfeiting film structure. In more detail, the present invention relates to an anti-counterfeiting film structure capable of implementing an image for determining authenticity using a pattern for determining authenticity.

Counterfeiting of expensive items such as software, CDs, DVDs, securities, liquor, and medicines has emerged as a major social problem. Because most of the products produced by counterfeiting have low quality, the company suffers enormous damage, such as undermining the trust gained through great efforts by such counterfeit acts. In order to solve such a forgery problem, companies are making efforts to prevent the distribution of counterfeit products by giving their products a technology that makes it difficult to counterfeit or determine the genuine and counterfeit products.

A hologram is a representative thing given to a product to prevent counterfeiting. In order to design a hologram, a hologram is designed using an interference shape between the reference light and the object light reflected from the object as the reference light and the object light irradiated to the object using a beam splitter.

The hologram is a medium in which interference fringes that reproduce a three-dimensional image are recorded and is made using the principle of holography. Accordingly, the hologram can implement a specific image by irradiating the reproduced light having the same frequency, wavelength, and phase as the reference light to the interference fringe at a specific angle. Also, the color or shape of the reflected light may change depending on the viewing angle.

However, since there is a limit to the information that can be recorded as a hologram, it is difficult to produce an elaborate hologram. Furthermore, there is a limit that the reproduced light must have the same phase, wavelength, and frequency as the reference light. This problem has become a serious problem that the duplication is easy as the hologram starts to be duplicated by a hologram duplication mechanism such as a digital scanner. In addition, the hologram pattern forming the hologram is regular as it has a certain shape.

Accordingly, in recent years, a technology for recording information on an anti-counterfeiting film using a nano-imprinting method has been introduced. The nano-imprinting method is a method of forming a diffraction pattern on an anti-counterfeiting film by using a mold having a nano pattern, and has been widely used in recent years because it can record a lot of information at low cost.

In general, the anti-counterfeiting film is irradiated in a straight direction so that the laser light transmitted through the inside is diffracted in a certain direction. Accordingly, after the laser light irradiated in a straight direction toward the anti-counterfeiting film passes through the anti-counterfeiting film, an image for anti-counterfeiting is realized by light diffracted by the diffraction pattern.

In recent years, there is a need to develop a film structure for anti-counterfeiting that implements a plurality of different images.

Accordingly, an object of the present invention is to provide an anti-counterfeiting film structure capable of implementing a plurality of different authenticity determination images.

In order to achieve the above object, the anti-counterfeiting film structure according to an embodiment of the present invention is provided on a base and on the base, and has a diffraction pattern to obtain a first authenticity determination image using light in the visible region. It is provided to be implemented and includes a composite image device capable of implementing a second authenticity determination image by selectively reacting to a specific wavelength.

In one embodiment of the present invention, the composite image device may be made of a taggant material.

In one embodiment of the present invention, the composite image element is provided to contact the first image element and the first image element having the diffraction pattern, and a second image element that implements the second authenticity determination image It may include.

Here, the composite image element is a material interposed between the first and second image elements, provided along a profile of the diffraction pattern, and having a refractive index difference of at least 0.1 or more from a material constituting the first image element. It may further include a refractive index control thin film made.

In addition, the refractive index adjusting thin film may include at least one of gold, silver, and aluminum.

Meanwhile, the second image element may include a functional material capable of implementing the second authenticity determination image by converting optical properties according to any one of heat, ultraviolet rays, magnetism, humidity, and pressure.

Since the anti-counterfeiting film structure according to the embodiments of the present invention includes a composite image element, a plurality of authenticity determination images including a first authenticity determination image and a second authenticity determination image may be implemented.

In particular, since the composite image device includes a taggant material, the second authenticity determination image may be displayed by selectively reacting to light having a specific wavelength.

In addition, when the composite image device includes a functional material, the second authentic board image may be displayed according to heat, humidity, pressure, or magnetism.

1 is a cross-sectional view illustrating an anti-counterfeiting film structure according to an embodiment of the present invention.
2 is a cross-sectional view illustrating an anti-counterfeiting film structure according to another embodiment of the present invention.
3 is a cross-sectional view illustrating a phase difference of reflected light reflected from a first image element included in an anti-counterfeiting film structure.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present invention, various modifications can be made and various forms can be obtained, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific form of disclosure, it is to be understood as including all changes, equivalents, and substitutes included in the spirit and scope of the present invention. In the accompanying drawings, the sizes and amounts of objects are shown to be enlarged or reduced from the actual size for clarity of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, terms such as "comprise" or "include" are intended to designate the existence of features, steps, functions, components, or combinations thereof described in the specification, and other features, steps, functions, and components It is to be understood that the possibility of addition or presence of or combinations thereof is not preliminarily excluded.

Meanwhile, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention belongs. Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in this application. Does not.

1 is a cross-sectional view illustrating an anti-counterfeiting film structure according to an embodiment of the present invention.

Referring to FIG. 1, the anti-counterfeiting film structure according to an embodiment of the present invention includes a base 111 and a composite image element 130. The anti-counterfeiting film structure may implement a first authenticity determination image and a second authenticity determination image different from each other according to the wavelength of light applied from the outside.

The base 111 may be made of a polymer material. For example, the base 111 may be made of a PET material.

A composite image element 130 is provided on the upper surface of the base 111.

The composite image device 130 may implement the first authenticity determination image using visible light. That is, a diffraction pattern is formed on the upper surface of the composite image element 130. The diffraction pattern may have various sizes and shapes. For example, the shape of the diffraction pattern may include a stripe shape, a mosaic shape, a pyramid shape, and the like. The diffraction pattern may be defined as a pattern for using diffraction characteristics for implementing a specific image through a design algorithm including Fourier transform and Fourier inverse transform processes.

The diffraction pattern may be formed through a hot embossing process, a nanoimprinting process, or a transfer printing process.

A first authenticity determination image may be implemented according to interference between reflected lights reflected from the diffraction pattern by using a difference in refractive index between the diffraction pattern and the air above the diffraction pattern.

Meanwhile, the composite image element 130 may selectively react to a specific wavelength to implement a second authenticity determination image.

For example, the composite image device 130 may include a taggant material. The taggant material may be excited by light having a specific wavelength applied from the outside to emit a detectable amount of radiation in the infrared, visible, and/or ultraviolet spectrum. Accordingly, the composite image device may selectively react to a specific wavelength to generate light having a specific spectrum, thereby displaying a second authentic image for a plate bottom.

Typical luminescent taggants include at least a host crystal lattice, emissive ions (eg, rare earth ions capable of absorbing/emitting electromagnetic radiation or releasing energy transferred through other ions), or “sensitizing” ions. .

That is, the generation of radiation by the luminescent taggant is the absorption of incident radiation by the emission ions or by either or both of the host material and the sensitizing ions, the energy transfer from the host material/sensitizing ions to the releasing ions, and the emission ions. Is achieved by the radiation of the transferred energy by

For a specific luminescent taggant that produces an observable energy emission, the spectral position of the higher spectral energy content in its emission can be used to uniquely identify the luminescent taggant from other compounds. This, spectral signature is due to rare earth ions. However, spectral perturbation may exist due to the influence of the host material on the various emissive ions, typically through crystal field strength and splitting.

The film structure for authenticity determination including the composite image element 130 including the luminescent taggant may be attached to a specially designed genuine article.

More specifically, the manufacturer may attach a film structure for authenticity determination including the composite image element 130 made of a known taggant material to the authentic article.

At this time, one will have knowledge (eg, stored information and/or various spectral filters) about the spectral characteristics of emission related to the luminescent taggant and the wavelength of absorbable excitation energy. Thereby, when a genuine article for authentication is provided, the authentication equipment irradiates external light having excitation energy having a wavelength corresponding to a known wavelength of the absorption feature of the luminescent taggant that directly or indirectly causes the desired emission. The composite image device 100 including the target material may implement a second authenticity determination image having a spectral field for any emission.

Examples of light of the specific wavelength may include ultraviolet rays. For example, when external light includes visible light and ultraviolet light, the visible light is reflected from the diffraction pattern to implement a first authenticity determination image, while the ultraviolet light reaches the composite image element 130 . In this case, the taggant material included in the composite image element 130 is excited by the ultraviolet light to implement a second authenticity determination image.

2 is a cross-sectional view illustrating an anti-counterfeiting film structure according to another embodiment of the present invention.

2, the anti-counterfeiting film structure according to another embodiment of the present invention includes a base 111 and a composite image element 130.

The composite image device 130 includes a first image device 131, a second image device 132, and a refractive index adjustment thin film 137.

Since the first image element 131 has a diffraction pattern, a first authenticity determination image may be implemented using visible light.

Meanwhile, the second image element 132 includes a taggant material that selectively reacts to specific wavelengths excluding visible light.

When the second image element 132 includes a taggant material, the taggant material is excitation by light having a specific wavelength applied from the outside and detectable in the infrared, visible, and/or ultraviolet spectrum. It can emit positive radiation.

Alternatively, when the second image element 132 implements a second determination image according to an application condition, the application condition may include heat, magnetism, humidity, or pressure. In this case, according to the application condition, the second image element 132 may display a second authenticity determination image.

The second image element 132 is positioned on the refractive index adjusting thin film 137. The second image device includes a functional material.

When the functional material includes a thermally reactive material, the second image element 132 may have a property of discoloration according to temperature.

Examples of the heat-reactive material may include a mixture of a Zion pigment and a synthetic resin. Zion pigments included in the thermally reactive material may have a plurality of types. As a result, the second image element 132 may implement various color changes according to temperature.

The functional material may be made of magnetic particles and a solvent. The magnetic particles are aligned in a direction parallel to the direction of the first magnetic field to form a particle chain. On the other hand, when a second magnetic field is applied to the particle chain, the particle chain moves in a direction close to the upper surface. On the other hand, when the intensity or direction of the second magnetic field is changed or a third magnetic field that is opposite to the direction of the second magnetic field is applied, the particle chain moves away from the upper surface, thereby adjusting the contrast and color of the second authenticity determination image. I can.

Meanwhile, the second image element 132 may implement a second authenticity determination image in response to humidity. In this case, the second image element 132 may include cobalt chloride. Alternatively, the second image device 132 may include a pigment and a humidity indicator solution. In this case, as the pigment, for example, a blue pigment manufactured by VIDHI (manufactured by Dyestuff Mfg.) may be used. In this case, the second image element 132 may change color to green in a dry state and purple in a humid state to detect a change in humidity.

Alternatively, the second image element 132 may include a liquid medium and a pigment distributed in the medium and having different orientations according to the applied pressure.

That is, the liquid medium is sufficiently viscous so that the pigment, which can be aligned by pressure, is not reoriented when externally applied pressure is released. When a pressure is applied to the surface of the second image element 120 in a positive direction or a tangential direction (shearing), the liquid medium and the pigment are disturbed and the appearance of the element may be changed. At this time, the pigment may change from an equilibrium state to a disordered state by the applied pressure. On the other hand, upon removal of the pressure, the pigment returns to its aligned state.

The refractive index adjusting thin film 137 is interposed between the first image element 131 and the second image element 132. In addition, the refractive index adjusting thin film 137 is formed along a profile of a diffraction pattern included in the first image element 131. Accordingly, the refractive index adjusting thin film 137 may be formed to have a uniform thickness. The refractive index adjusting thin film 137 may be made of a material having a refractive index difference of at least 0.1 or more from a material constituting the first image element 131.

That is, if the refractive index adjusting thin film 137 is omitted, the difference in refractive index between the first image element 131 and the second image element 132 may be less than 0.1. In this case, it is difficult for the first image element 131 to implement a first authenticity determination image using the visible light. On the other hand, when the refractive index adjusting thin film 137 is interposed between the first image element 131 and the second image element 132, the refractive index between the refractive index adjusting thin film 137 and the first image element 137 The difference can be adjusted to 0.1 or more. Accordingly, the first image element 131 can easily implement a first authenticity determination image using visible light.

The refractive index control thin film 137 may include a light reflective metal material such as gold, silver, and aluminum.

The thickness of the refractive index adjustment thin film 137 may be adjusted according to the required light transmittance. For example, the refractive index control thin film 137 may have a thickness of 1 nm to 4 nm.

The phase of the reflected light reflected from the surface of the refractive index adjusting thin film 137 changes due to the step difference formed in the diffraction pattern of the refractive index adjusting thin film 137. Accordingly, a specific diffraction image may be implemented by the reflected lights being mutually interfered.

The anti-counterfeiting film structure according to an embodiment of the present invention includes a composite image element 130 that implements a first authenticity determination image using visible light and selectively reacts to a specific wavelength to implement a second authenticity determination image do. Accordingly, the composite image element 130 may independently implement the first and second authenticity determination images, respectively. Therefore, the film structure for authenticity determination may implement a plurality of images.

3 is a cross-sectional view illustrating a phase difference of reflected light reflected from a first image element included in an anti-counterfeiting film structure.

3, when there is a height difference h between diffraction patterns and the diffraction pattern has np(=1+p), the phase difference (φ1-φ2) at different positions is Equation 1 below. Is the same.

Here, k ₀ (=2π/λ), p is a difference value greater than 1, which is the refractive index of air, and h is the difference in height of the diffraction pattern.

Using the phase difference, an image for authenticity determination can be implemented from a diffraction pattern.

Although the present invention has been shown and described with reference to a preferred embodiment as described above, it is not limited to the above embodiment, and within the scope of the spirit of the present invention, various Transformation and change are possible. Such modifications and variations are to be viewed as falling within the scope of the present invention and the appended claims.

111: base 130: composite image element
131: first image element 132: second image element
137: refractive index control thin film

Claims (6)

Base; And
It is provided on the base, has a diffraction pattern, and is provided to implement a first authenticity determination image using light in the visible region, and selectively reacts to light of a specific wavelength except for the visible region Including a composite image element capable of implementing a judgment image,
The composite image device,
A first image element having the diffraction pattern and provided to implement a first authenticity determination image using light in the visible light region;
A second image element disposed on the first image element and made of a target material selectively reacting to the light of the specific wavelength to implement the second authenticity determination image; And
It is interposed between the first and second image elements, provided along the profile of the diffraction pattern, including a refractive index control thin film made of a material having a refractive index difference of at least 0.1 or more from a material constituting the first image element Anti-counterfeiting film structure, characterized in that. delete delete delete The film structure for anti-counterfeiting according to claim 1, wherein the refractive index control thin film comprises at least one selected from a group of light reflective metals formed by gold, silver and aluminum. The method of claim 1, wherein the second image element further comprises a functional material capable of implementing the second authenticity determination image by converting optical properties according to any one of heat, magnetism, humidity, and pressure. Anti-counterfeiting film structure.

Images