JP2020021045A - Transflective anti-counterfeit film - Google Patents

Abstract

To provide a transflective anti-counterfeit film which overcame the limitation of optical transparency that a transmission type anti-counterfeit film has.SOLUTION: A transflective anti-counterfeit film comprises a base 110, a diffractive optical element layer 130 provided on the base 110 and having a diffraction pattern for implementing an authenticity determination image, and a light transmissivity adjustment thin film 150 formed along a profile of the diffraction pattern on the diffractive optical element layer 130 and capable of making incident light reflect and penetrate partially. With this, the transflective anti-counterfeit film can implement a diffraction image on both sides of the film by making the incident light reflect and penetrate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a transflective anti-counterfeit film, and more particularly, to a semi-transmissive anti-counterfeit film capable of realizing an image for authenticity judgment using a pattern for authenticity judgment.

  Forgery of expensive items such as software, CDs, DVDs, securities, liquors, medicines, etc. has become a major social problem. Since many counterfeit products have low quality, such counterfeiting has caused enormous damage such as losing the trust obtained by making a lot of efforts. In order to solve such a counterfeiting problem, manufacturers are striving to prevent counterfeiting by providing technologies that make counterfeiting difficult or technologies for determining genuine and counterfeit products.

  A hologram is typically given to a product to prevent forgery. In order to design a hologram, a hologram is designed using an interference phenomenon between the object light reflected from the object and the reference light, with the object light and the reference light irradiating the object using a beam splitter.

  The hologram is a medium on which interference fringes for reproducing a three-dimensional image are recorded, and is created by using the principle of holography. Thus, the hologram can realize a specific image by irradiating the interference fringes with the reproduction light having the same frequency, wavelength, and phase as the reference light at a specific angle. Also, the color or form of the reflected light may change depending on the viewing angle.

  However, since there is a limit to the information that can be recorded on a hologram, there has been a problem that it is difficult to produce a sophisticated hologram. Consequently, there is a limit that the reproduction light must have the same phase, wavelength and frequency as the reference light. From such a problem, hologram duplication is easily performed by a hologram duplication device such as a digital scanner, and the problem becomes serious. Further, the hologram pattern forming the hologram is regular since it has a certain shape.

  Accordingly, a technology for recording information on a forgery prevention film by a nanoimprinting method has recently been introduced. The nanoimprinting method is a method of forming a diffraction pattern on a forgery prevention film using a mold having a nanopattern, and is widely used in recent years because much information can be recorded at low cost. ing.

  Usually, the anti-counterfeit film is irradiated in the straight direction so that the laser transmitted therethrough is diffracted in a certain direction. Accordingly, after the laser beam irradiated in the straight direction on the forgery prevention film passes through the forgery prevention film, the forgery prevention pattern is realized by the light diffracted by the diffraction pattern.

  However, the transmission type forgery prevention film has a problem that it is difficult to apply it to products of various shapes including a three-dimensional bulk. Further, since the transmission type anti-counterfeit film itself must secure light transmittance as a whole, the material of the transmission type anti-counterfeit film is limited.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a transflective anti-counterfeit film that overcomes the light transmittance limitation of a transmissive anti-counterfeit film. With the goal.

  In order to achieve the above object, a transflective anti-counterfeiting film according to an embodiment of the present invention has a base and a diffraction pattern provided on the base and for embodying an image for authenticity determination. A diffractive optical element layer; and a light transmittance adjusting thin film formed on the diffractive optical element layer according to the profile of the diffraction pattern and capable of partially reflecting and transmitting incident light.

  In one embodiment of the present invention, the light transmittance controlling thin film has a light transmittance within a range of 40 to 60% with respect to light having a wavelength in a visible light region, and both upper and lower portions of the base. , An image for authenticity determination can be realized.

  In an embodiment of the present invention, the light transmittance controlling thin film may include at least one selected from the group consisting of light reflective metals including gold, silver and aluminum.

  According to an embodiment of the present invention, the base may further include at least one information pattern unit storing information at an upper portion or a lower portion of the base.

  Here, the light transmittance adjusting thin film may have a thickness adjusted to have a maximum transmittance for incident light having a wavelength of 500 to 600 nm.

  In this case, the information pattern unit may include a QR pattern layer provided on a lower surface of the base and including QR information.

  The light transmittance controlling thin film may have a thickness adjusted to have a transmittance of less than 50% with respect to incident light having a wavelength of 500 to 600 nm.

  In this case, the information pattern unit may include a hologram pattern layer provided on the light transmittance adjusting thin film and using incident light having a wavelength of 500 to 600 nm as reproduction light. Also, a transparent bonding layer may be further provided between the light transmission controlling thin film and the hologram pattern layer, for bonding the light transmission controlling thin film and the hologram pattern layer to each other.

  The light transmittance adjusting thin film has a light transmittance within a range of 40 to 60% with respect to light having a wavelength in a visible light region, and the information pattern portion includes a hologram formed on the base. It may include a pattern layer and a QR pattern layer formed below the base.

  In one embodiment of the present invention, a flattening layer provided on the light transmission control thin film, and the flattening layer and the light transmission control sandwiched between the light transmission control thin film and the flattening layer. And a bonding layer for mutually bonding the thin film.

  According to the transflective anti-counterfeit film according to an embodiment of the present invention, a nano-sized fine pattern can be realized by providing a diffractive optical element that can replace a hologram. Accordingly, a complex image can be easily realized, and a diffraction pattern having an irregularly random shape or size can be realized. Also, an image having a plurality of colors can be easily realized using light having various wavelengths and phases.

  In addition, unlike a conventional transmission type forgery prevention film, a forgery determination image can be embodied toward both the upper surface and the lower surface of the base. Therefore, the authenticity of the target object can be easily determined regardless of the degree of light transmittance of the target object.

  In addition, since a separate hologram pattern layer or QR pattern layer is additionally provided, it is possible to more accurately perform forgery determination or store additional information for tracking and managing products.

  On the other hand, since the flattening layer and the bonding layer are additionally provided, the thickness of the semi-transmissive forgery prevention film can be effectively adjusted by changing the thickness of the bonding layer.

1 is a cross-sectional view illustrating a semi-transmissive forgery prevention film according to an embodiment of the present invention. 2 is a graph showing light transmittance according to the thickness of the light transmittance adjusting thin film of FIG. 1. FIG. 6 is a cross-sectional view illustrating a semi-transmissive forgery prevention film according to another embodiment of the present invention. FIG. 9 is a cross-sectional view illustrating a transflective anti-counterfeit film according to another embodiment of the present invention. FIG. 9 is a cross-sectional view illustrating a transflective anti-counterfeit film according to another embodiment of the present invention. 3 is a flowchart illustrating a method of manufacturing a semi-transmissive forgery prevention film according to an embodiment of the present invention. It is the photograph which imaged the hologram as a comparative example. It is the photograph which imaged the transflective type anti-counterfeit film which has the diffractive optical element of this invention. It is sectional drawing for demonstrating the phase difference of the light which transmitted the diffraction pattern contained in the transmission type forgery prevention film. It is sectional drawing for demonstrating the phase difference of the light which transmitted the diffraction pattern contained in the reflection type forgery prevention film.

  Hereinafter, a ground clamp unit and a substrate support assembly according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Although the present invention can be variously modified and can have various forms, specific embodiments will be illustrated in the drawings and described in detail in the text. However, it is to be understood that this is not to limit the invention to the particular forms of disclosure, but to include all modifications, equivalents, or alternatives falling within the spirit and scope of the invention. In the description of the drawings, like reference numerals have been assigned to like components. In the accompanying drawings, the dimensions of the structures have been exaggerated for clarity of the invention.

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

  The terms used in the specification are intended to describe certain embodiments only, and shall by no means restrict the present invention. The singular expression includes the plural unless the context clearly dictates otherwise. As used herein, terms such as "comprising" or "having" are intended to mean the presence of a feature, number, step, act, component, component, or combination thereof, as described herein. It is to be understood that this does not exclude the possibility of the presence or addition of one or more other features or numbers, steps, acts, components, parts, or combinations thereof.

  Unless defined otherwise, all terms used herein, including technical or scientific terms, are commonly understood by one of ordinary skill in the art to which this invention belongs. It has the same meaning as the one. Terms such as those defined in commonly used dictionaries should be construed to have a meaning consistent with the meaning in the context of the relevant art and, unless explicitly defined in the present application, ideal Or is not interpreted in an overly formal sense.

  FIG. 1 is a cross-sectional view illustrating a reflective-transmissive type forgery prevention film according to an embodiment of the present invention.

  Referring to FIG. 1, a transflective anti-counterfeit film 100 according to an embodiment of the present invention includes a base 110, a diffractive optical element layer 130, and a light transmittance controlling thin film 150. In the semi-transmissive forgery prevention film 100, LED light or laser light incident from the outside is partially reflected from the light transmittance adjusting thin film 150 and partially transmitted. Accordingly, a specific image can be realized toward both the upper and lower portions of the base 110. At this time, the specific image may be an image for authenticity determination. For example, the specific image may include a trademark or a logo of a manufacturer of a subject that needs to be authenticated.

  The base 110 may be made of a polymer material. For example, the base 110 may be made of a PET material. In addition, a double-sided adhesive tape (not shown) may be formed on a lower surface of the base 110 so that the base 110 can be attached to a specific product.

  A diffractive optical element layer 130 is provided on the upper surface of the base 110.

  A diffraction pattern is formed on the upper surface of the diffractive optical element layer 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 using a diffraction characteristic for implementing a specific image through a design algorithm including a Fourier transform and an inverse Fourier transform.

  The diffraction pattern may be formed by a hot embossing process, a nano-imprinting process, or a transfer printing process.

  The light transmittance adjusting thin film 150 is formed along the profile of the diffraction pattern. Accordingly, the light transmittance controlling thin film 150 may be formed to have a uniform thickness. The light transmittance controlling thin film 150 reflects a part of the light incident from the outside and implements a specific image on an upper part thereof, while transmitting a part of the external light and displays a specific image on a lower part thereof. Can be embodied. Therefore, the transflective anti-counterfeiting film 100 including the light transmittance adjusting thin film 150 can be used regardless of the light transmittance of the authenticity determination target object.

  The light transmittance controlling thin film 150 may include a light reflective metal material such as gold, silver, and aluminum.

  The light transmittance of the light transmittance adjusting thin film 150 may be adjusted according to its thickness. For example, the light transmittance controlling thin film 150 may have a thickness of 1 nm to 4 nm.

  The phase of light reflected on the surface of the light transmittance adjusting thin film 150 changes according to a step formed in the diffraction pattern. Accordingly, a specific diffraction image can be realized by the reflected light interfering with each other.

  FIG. 2 is a graph illustrating light transmittance according to the thickness of the light transmittance controlling thin film of FIG.

  Referring to FIG. 2, when the light transmittance adjusting thin film 150 is made of gold, the light transmittance according to the wavelength for each thickness is shown.

  When the light transmittance adjusting thin film 150 is made of gold, the light transmittance adjusting thin film 150 may have a thickness of 2 to 4 nm. Accordingly, the light transmittance controlling thin film may have a light transmittance of 40 to 60% in a visible light region.

  In particular, it is estimated that the light transmittance adjusting thin film having a thickness of 3 nm has a light transmittance of about 50% with respect to external light of 550 nm.

  According to an embodiment of the present invention, unlike the existing transmission type forgery prevention film, the semi-transmission type forgery prevention film 100 adheres to an object having various shapes including a three-dimensional bulk. It is possible. That is, in the case of an existing transmission type forgery prevention film, since light implements an image for authenticity determination using transmitted light transmitted through the product, when the target object is opaque, the transmission type forgery is prevented. It is difficult to use a film for prevention.

  On the other hand, the transflective anti-counterfeiting film 100 according to the embodiment of the present invention has an advantage that it can be used regardless of various shapes or materials of an attached object.

  In one embodiment of the present invention, the transflective anti-counterfeit film 100 further includes a planarizing layer 190 and a bonding layer 170.

  The planarization layer 190 is provided on the light transmission control thin film 150. The planarization layer 190 removes a step formed in the diffraction pattern and planarizes the entire upper surface.

  The planarization layer 190 is provided to cover the light transmittance controlling thin film 150. Accordingly, the flattening layer 190 can protect the light transmittance adjusting thin film 150 and thus the diffractive optical element layer 130 from external impact. Further, since the flattening layer 190 entirely covers the diffractive optical element layer 130, the duplication of the transflective anti-counterfeiting film 100 can be suppressed.

  The planarization layer 190 may be formed of any one of a light transmitting resin including PVC, PMMA, PET, PT, acrylic, and epoxy.

  The bonding layer 170 is sandwiched between the planarization layer and the light transmission control thin film. The bonding layer 170 bonds the flattening layer 190 and the light transmission control thin film 150 to each other. The bonding layer 170 may be formed by a laminating process. The bonding layer 170 may bond the planarization layer 190 and the light transmission control thin film 150 to each other by cooling, for example.

  FIG. 3 is a cross-sectional view illustrating a transflective anti-counterfeit film according to an embodiment of the present invention.

  Referring to FIG. 3, a transflective anti-counterfeiting film 100 according to an embodiment of the present invention includes a base 110, a diffractive optical element layer 130, a light transmittance controlling thin film 150, and an information pattern part. The information pattern unit may include, for example, a hologram pattern layer 180.

  The hologram pattern layer 180 is provided on the light transmittance controlling thin film 150. The hologram pattern layer 180 uses reflected light in which part of incident light incident from the outside is reflected from the light transmittance adjusting thin film 150. Accordingly, the transflective anti-counterfeiting film 100 can embody a hologram on an upper portion thereof.

  On the other hand, a part of the incident light that is incident from the outside passes through the light transmittance adjusting thin film 150, and the transmitted light is a diffraction pattern formed on the diffractive optical element layer 130, and the light transmittance adjusting thin film 150 A specific image can be realized by a difference in refractive index between the diffractive optical element layer 130 and the diffractive optical element layer 130. Accordingly, the semi-transmissive forgery prevention film 100 can determine the presence or absence of forgery using the specific image.

  As a result, the transflective anti-counterfeiting film 100 can embody a hologram on an upper portion thereof and simultaneously embody a specific image on a lower portion thereof.

  Here, the light transmittance adjusting thin film 150 may have a thickness adjusted to have a transmittance of less than 50% with respect to incident light having a wavelength of 500 to 600 nm. Accordingly, since the light transmittance controlling thin film 150 has a relatively high light reflectivity with respect to the incident light, light required for implementing a hologram can reach the hologram pattern layer 180 in a greater amount. .

  FIG. 4 is a cross-sectional view illustrating a semi-transmissive forgery prevention film according to an embodiment of the present invention.

  Referring to FIG. 4, a transflective anti-counterfeit film 100 according to an embodiment of the present invention includes a base 110, a diffractive optical element layer 130, a light transmittance controlling thin film 150, and an information pattern part. The information pattern unit may include, for example, a QR pattern layer 120.

  The QR pattern layer 120 is located below the base 110. The QR pattern layer 120 uses transmitted light in which part of incident light incident from the outside passes through the light transmittance adjusting thin film 150. Accordingly, the semi-transmissive forgery prevention film 100 can recognize information stored in the QR pattern layer 120 located below the bonding layer 170. That is, a QR scanner (not shown) scans the QR pattern layer 120 to easily track and manage a target using the information, for example, a production lot.

  As a result, the transflective anti-counterfeit film 100 can display a specific image at the lower portion thereof and read out the QR information formed at the lower portion.

  Here, the light transmittance adjusting thin film 150 may have a thickness adjusted to have a maximum transmittance for incident light having a wavelength of 500 to 600 nm. Accordingly, since the light transmittance adjusting thin film 150 has relatively high light transmittance with respect to the incident light, it can reach the QR pattern layer 120 in a larger amount. Accordingly, the information stored in the QR pattern layer 120 can be effectively recognized by the QR scanner.

  FIG. 5 is a cross-sectional view illustrating a semi-transmissive forgery prevention film according to an embodiment of the present invention.

  Referring to FIG. 5, a transflective anti-counterfeit film 100 according to an embodiment of the present invention includes a base 110, a diffractive optical element layer 130, a light transmittance controlling thin film 150, and an information pattern part. The information pattern unit may include, for example, a hologram pattern layer 180 and a QR pattern layer 120.

  The hologram pattern layer 180 is provided on the light transmittance controlling thin film 150. The hologram pattern layer 180 uses reflected light in which part of incident light incident from the outside is reflected from the light transmittance adjusting thin film 150. Accordingly, the transflective anti-counterfeiting film 100 can embody a hologram on an upper portion thereof.

  Meanwhile, the QR pattern layer 120 is located below the base 110. The QR pattern layer 120 uses transmitted light in which part of incident light incident from the outside passes through the light transmittance adjusting thin film 150. Accordingly, the semi-transmissive forgery prevention film 100 can recognize information stored in the QR pattern layer 120 located below the base 110. That is, the QR scanner scans the QR pattern layer 120 to easily track and manage a target using the information, for example, a production lot.

  FIG. 6 is a flowchart illustrating a method of manufacturing a semi-transmissive forgery prevention film according to an embodiment of the present invention.

  Referring to FIGS. 1 and 6, in the method of manufacturing a transflective anti-counterfeit film according to an embodiment of the present invention, first, a diffractive optical element layer 130 is formed on one surface of a base 110 (S110). The diffractive optical element layer 130 having the diffraction pattern may be formed by a hot embossing process, a nano-imprinting process, or a transfer printing process.

  Subsequently, a light transmittance adjusting thin film 150 for reflecting and transmitting the light incident from outside is formed along the profile of the diffraction pattern (S130). The light transmittance controlling thin film 150 may be formed by an atomic layer deposition process, a sputtering process, or an ion beam process.

  The light transmittance controlling thin film 150 may be formed using a light reflective metal material such as gold, silver, and aluminum. The light transmittance controlling thin film 150 may have a thickness of 1 nm to 4 nm.

  On the other hand, an information pattern layer such as the QR pattern layer 120 is formed on the other surface of the base 110. On the other hand, an information pattern layer such as a hologram pattern layer 180 (see FIG. 5) is formed on a separate base.

  Then, the information pattern layer is bonded on the light transmittance adjusting thin film 150. Accordingly, a semi-transmissive forgery prevention film 100 including the information pattern layer and the light transmittance adjusting thin film 150 is manufactured.

  FIG. 7A is a photograph of a hologram taken as a comparative example. FIG. 7B is a photograph of a transflective anti-counterfeit film having the diffractive optical element of the present invention.

  Referring to FIG. 7A and FIG. 7B, the hologram is a transflective type anti-counterfeiting film having a diffractive optical element according to the present invention, in which interference fringes are repeatedly formed with periodicity. Can be confirmed to have a structure in which irregular stripes are formed as multiple layers.

  FIG. 8 is a cross-sectional view for explaining a phase difference of light transmitted through a diffraction pattern included in a transmission type forgery prevention film.

Referring to FIG. 8, when there is a height difference h between diffraction patterns and the diffraction patterns have n _p (= 1 + p), the phase difference (φ ₁ −φ ₂ ) at different positions is calculated by the following mathematical formula. Equation 1 is as follows.

Φ ₁ -Φ ₂ = k ₀ × p × h (Equation 1)
Here, k ₀ (= 2π / λ), p is a difference value larger than 1, which is the refractive index of air, and h is a difference between the heights of the diffraction patterns.

  An image for authenticity determination can be realized from the diffraction pattern using the phase difference.

  FIG. 9 is a cross-sectional view for explaining a phase difference of light transmitted through the diffraction pattern included in the reflection type forgery prevention film.

Referring to FIG. 9, when there is a height difference h between the diffraction patterns and the diffraction patterns have n _p (= 1 + p), the phase difference (φ ₁ −φ ₂ ) at different positions is calculated by the following mathematical formula. Equation 2 is shown.

Φ ₁ '-Φ ₂ ' = -k ₀ × 2h '(Equation 2)
Here, k ₀ (= 2π / λ), p is a difference value larger than 1, which is the refractive index of air, and h is a height difference of the diffraction pattern.

  An image for authenticity determination can be realized from the diffraction pattern using the phase difference.

  Although the present invention has been illustrated and described with reference to the preferred embodiments as described above, the present invention is not limited to the above-described embodiments, and ordinary knowledge in the technical field to which the present invention pertains without departing from the technical spirit of the present invention. Various modifications and changes are possible by those who have. It should be noted that such modified examples and modified examples are included in the appended claims.

REFERENCE SIGNS LIST 100 transflective anti-counterfeit film 110 base 130 diffractive optical element layer 150 light transmittance adjusting thin film 170 bonding layer 190 flattening layer

Claims (11)

Base and
A diffractive optical element layer provided on the base and having a diffraction pattern for implementing an image for authenticity determination,
A light transmittance adjusting thin film formed on the diffractive optical element layer along the profile of the diffraction pattern and capable of partially reflecting and transmitting incident light. Anti-counterfeit film.   The light transmittance adjusting thin film has a light transmittance within a range of 40% to 60% with respect to light having a wavelength in a visible light region, and an image for authenticity determination toward both upper and lower portions of the base. The transflective anti-counterfeit film according to claim 1, wherein the anti-counterfeit film according to claim 1 can be realized.   The semi-transmissive anti-counterfeit film according to claim 1, wherein the light transmittance adjusting thin film includes at least one selected from a light-reflective metal group consisting of gold, silver and aluminum.   The semi-transmissive anti-counterfeit film according to claim 1, further comprising at least one information pattern part storing information at an upper part or a lower part of the base.   The semi-transparent forgery according to claim 4, wherein the light transmittance adjusting thin film has a thickness adjusted to have a maximum transmittance for incident light having a wavelength of 500 to 600 nm. Film for prevention.   The semi-transmissive forgery prevention film according to claim 5, wherein the information pattern portion includes a QR pattern layer provided on a lower surface of the base and including QR information.   The transflective film according to claim 4, wherein the light transmittance adjusting thin film has a thickness adjusted to have a transmittance of less than 50% for incident light having a wavelength of 500 to 600 nm. Anti-counterfeit film.   The semi-transmission according to claim 7, wherein the information pattern portion includes a hologram pattern layer provided on the light transmittance adjusting thin film and using incident light having a wavelength of 500 to 600 nm as reproduction light. Anti-counterfeit film.   9. The method according to claim 8, further comprising a transparent bonding layer sandwiched between the light transmittance adjusting thin film and the hologram pattern layer, for bonding the light transmittance adjusting thin film and the hologram pattern layer to each other. Semi-transmission type forgery prevention film. The light transmittance adjusting thin film has a light transmittance within a range of 40 to 60% with respect to light having a wavelength in a visible light region,
The semi-transmission type forgery according to claim 4, wherein the information pattern portion includes a hologram pattern layer formed on an upper portion of the base and a QR pattern layer formed on a lower portion of the base. Film for prevention. A planarization layer provided on top of the light transmittance control thin film,
The method of claim 1, further comprising a bonding layer sandwiched between the light transmittance adjusting thin film and the flattening layer, the bonding layer being configured to mutually bond the flattening layer and the light transmittance adjusting thin film. The semi-transmissive forgery prevention film as described in the above.