KR20210073137A - Color-shifting security film and security product comprising the same - Google Patents

Abstract

Disclosed is a color conversion security film containing a transparent substrate in which an embossed part and an engraved part are repeatedly formed on one surface, and a color conversion layer formed in the engraved part, wherein a see-through region and an opaque region are provided by the embossed part and the engraved part, respectively. The color conversion security film according to the present invention exhibits a see-through effect through a transparent window together with a color conversion effect that changes color depending on a viewing angle. In addition, there is an effect that an area where the color conversion effect appears changes according to the viewing angle.

Description

Color Conversion Security Film and Security Products Containing Same {COLOR-SHIFTING SECURITY FILM AND SECURITY PRODUCT COMPRISING THE SAME}

The present invention relates to a color conversion security film and a security product including the same, and more particularly, to a color conversion security film having a simple structure and providing various visual effects according to viewing angles, and a security product including the same.

Security films such as banknotes, securities, gift certificates, passports, ID cards, and product labels are generally used to prevent forgery.

In addition, the number of cases in which such a security film is included in a product or its packaging for authenticity authentication is increasing.

The security film is implemented in the form of being included in the security document or produced in the form of a film and attached to the surface of the security document, and usually has a special visual effect. Examples of such visual effects include hologram, moire magnification, fluorescence, parallax motion, and color-shifting.

Among them, the color-shifting security element is a security element that changes color depending on the viewing angle of the observer, and it is being used in various ways because it can identify authenticity with the naked eye without using a separate authenticity identification device. The color conversion security element is typically implemented with color-shifting, hologram, and color-shifting ink.

The color conversion security element cannot be reproduced by simple scanning and copying, so it is a very effective technology in terms of preventing counterfeiting. However, as there are recent cases of forgery using similar films on the market, it is difficult to cope with advanced counterfeiting only with a simple color conversion effect. . Therefore, various security technologies have been proposed to counter such high-level forgery.

Such security technologies include a technology for strengthening security characteristics by combining a thin film interference layer and a diffraction pattern, a technology for disposing metal layers having different color tones to appear different color tones, etc. However, these technologies are manufactured due to the complicated implementation process. There are disadvantages in that the cost increases or the color conversion effect is insufficient.

Accordingly, there is a need for a color conversion security element technology capable of improving the anti-counterfeiting effect by providing various visual effects with a simple structure.

1. Korea Patent Publication No. 2004-0074073 (2004.08.21)

The present invention has been devised to solve the problems of the prior art, and an object of the present invention is to provide a color conversion security film with improved security by providing various visual effects with a simple structure and a security product including the same. Specifically, a color conversion security element and security product in which a color conversion effect that changes color depending on the viewing angle and a see-through effect through a transparent window appear together, and the area where the color conversion effect appears changes depending on the viewing angle intended to provide

In addition, another object of the present invention is to provide a color conversion security film and a security product in which a color conversion effect is exhibited by rotating about an axis perpendicular to the color conversion security film.

The object of the present invention is not limited to the above, and other objects and advantages of the present invention not mentioned can be understood by the following description.

The color conversion security film according to the present invention includes a transparent substrate in which an embossed part and an intaglio part are repeatedly formed on one surface and a color conversion layer formed in the intaglio part, and a see-through region and an opaque region are provided by the embossed part and the intaglio part, respectively characterized by being

The color conversion layer may include a structure in which a light absorption layer, a dielectric layer, and a reflective layer are stacked.

Also, a color and an observation area of the opaque region may be changed according to a viewing angle.

In this case, as the observation area of the opaque area changes, the area of the see-through area may change.

In addition, the engraved portion may include an inclined surface, and in a specific viewing angle range, only the color of the opaque region may change according to the viewing angle, but the observation area may not change. In this case, the specific viewing angle range may be a range from an angle perpendicular to the color conversion security film to an angle parallel to the inclined surface. In addition, as the viewing angle is increased beyond the angle parallel to the inclined plane, the observation area of the opaque area may increase and the area of the see-through area may be reduced.

The cross-section of the intaglio may be in a V-shape or a trapezoidal shape.

The present invention discloses a security product comprising the color conversion security film according to any one of the above. The color conversion security film may be adhered to the security product through an adhesive layer.

In addition, a printing layer may be provided on one surface of the color conversion security film on which the color conversion layer is formed.

According to an embodiment of the present invention, there is an effect of improving security by providing various visual effects with a simple structure of forming an embossed portion and an intaglio portion on a transparent substrate and forming a color conversion layer on the intaglio portion. Specifically, there is an effect that a see-through effect through a transparent window appears together with a color conversion effect in which a color changes according to a viewing angle, and an area in which the color conversion effect appears changes according to a viewing angle.

In addition, according to the present invention, by forming a color conversion layer on the inclined surface of the intaglio portion, there is an effect that the color conversion effect appears as it rotates about an axis perpendicular to the security film.

However, the effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those of ordinary skill in the art to which the present invention belongs from the following description.

1 is a cross-sectional view showing a color conversion security film according to the present invention.
2 is a view for explaining the visual effect according to the viewing angle of the color conversion security film according to the present invention.
3 is a flowchart of a method for manufacturing a color conversion security film according to an embodiment of the present invention.
4 is a schematic diagram of a pattern forming step of a color conversion security film according to an embodiment of the present invention.
5 is a flowchart illustrating a method for manufacturing a color conversion layer according to a first embodiment of the present invention.
6 is a schematic diagram of a method for manufacturing a color conversion layer according to a first embodiment of the present invention.
7 is a flowchart of a method for manufacturing a color conversion layer according to a second embodiment of the present invention.
8 is a schematic diagram of a method for manufacturing a color conversion layer according to a second embodiment of the present invention.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments of the present invention are provided to fully explain the present invention to those of ordinary skill in the art. The embodiments presented below may be modified in various other forms, and the scope of the present invention is not limited to the following embodiments, and all changes, equivalents or substitutes included in the spirit and scope of the present invention should be understood as including

Like reference numerals are used for like elements in describing the accompanying drawings. In the accompanying drawings, the dimensions of the structures may be enlarged or reduced than in reality in order to help a clear understanding of the present invention.

The terminology used herein is used only to describe specific embodiments, and is not intended to limit the present invention.

In this specification, it should be understood that terms such as “comprise” or “have” specify the presence of the listed features, and do not preclude the possibility of the presence or addition of one or more other features. In this specification, the term “and/or” is used only to distinguish one feature from another to describe the listed features, and these features are not limited by these terms. Where it is described in the following description that a first feature is connected, coupled or connected with a second feature, this does not exclude that a third feature may be described between the first feature and the second feature.

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

Hereinafter, a color conversion security film according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2 .

1 is a cross-sectional view of a color conversion security film 100 according to an embodiment of the present invention.

The color conversion security film 100 according to an embodiment of the present invention includes a light absorption layer 20 and a dielectric layer 40 on the substrate 10 and the intaglio portion 12 in which the embossed part 11 and the engraved part 12 are repeatedly formed. ) and a color conversion layer formed by laminating the reflective layer 50 .

The substrate 10 has a configuration that serves as a support for supporting the color conversion security film 100 as a whole, and may be a transparent synthetic resin film. The material of the substrate 10 is not particularly limited, but polycarbonate (PC), polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, polystyrene, acrylic resin, polyvinyl chloride ( PC), glycol azide-polyester, acrylonitrile-butadiene-styrene (ABS), and mixtures thereof may be at least one selected from the group consisting of.

On one surface of the substrate 10, the embossed part 11 and the engraved part 12 are repeatedly formed. The intaglio portion 12 is a portion in which a groove of a predetermined depth is formed from one surface of the substrate 10 . Although not shown in the cross-sectional view of FIG. 1 , the intaglio portion 12 may be formed as a groove elongated in the longitudinal direction (direction perpendicular to the ground, that is, the y-direction in FIG. 2 ). The cross-section of the intaglio part 12 may be a V-shape in which an inclined surface is formed as shown in FIG. 1 , but is not limited thereto. For example, the V-shape may be formed in a trapezoidal shape or a hemispherical shape in which the apex portion is flatly removed. The intaglio portions 12 may be regularly spaced apart from each other at regular intervals in the width direction (x-direction in FIG. 2 ), and one surface of the substrate 10 between the intaglio portions 12 forms an embossed portion 11 .

A color conversion layer is formed in the intaglio portion 12 . In an embodiment of the present invention, the color conversion layer may be formed in a structure in which the light absorption layer 20 , the dielectric layer 40 , and the reflective layer 50 are sequentially stacked.

The light absorbing layer 20 may be made of any light absorbing material having desired light absorbing properties. The thickness of the light absorption layer 20 may have a thickness in the range of 1 to 50 µm, preferably 3 to 15 µm, depending on a desired color change effect. Such a light absorption layer may be formed of a single material, may have a combination and arrangement of various materials, and may have the same or different physical thicknesses.

In addition, the light absorption layer 20 is selected from the group consisting of Cr, Al, Cu, Co, Ni, Zn, Sn, Ag, Pd, Pt, Ti, V, Fe, W, Mo, Rh, Nb, or a combination thereof. can be used by Preferably, it may be a Cr layer with a thickness of about 5 nm. The transmittance of the light absorption layer may be in the range of 30% to 65%.

The dielectric layer 40 is formed over the light absorption layer 20 . The dielectric layer 40 may be a silicon oxide film (SiO ₂ ), and its thickness may be adjusted in a range of approximately 200 to 550 nm. Various color conversion effects may be obtained according to the thickness of the dielectric layer 40 . That is, the thickness of the dielectric layer 40 may vary depending on the color to be expressed.

The reflective layer 50 may be made of various reflective materials, and a metal, a metal alloy, or a combination thereof having high reflectivity and easy deposition may be used. Preferably, aluminum (Al), which is easily formed by vacuum deposition and has high reflectance, may be used. The reflective layer 50 may have a thickness in the range of 1 to 200 nm, preferably 10 to 100 nm.

In addition, in order to improve the security of the color conversion security film 100, in addition to the color conversion layer, additional security elements such as a fluorescent layer, a magnetic layer, and an infrared layer may be further provided.

In the color conversion security film 100 having such a configuration, transparent regions (regions I and III) and opaque regions (regions II and IV) may be repeated in the width direction of the film (x-direction in FIG. 2 ). The transparent regions (regions I and III) are regions in which the color conversion layer is not formed, and the opaque regions (regions II and IV) are regions in which the color conversion layer is formed.

The color conversion security film 100 formed in this way can be applied to security products such as various security documents or products. The color conversion security film 100 may be inserted into a security product in the form of a silver wire or manufactured in the form of a sticker and attached to the surface. To this end, the color conversion security film 100 may further include an adhesive layer (not shown). For example, the color conversion security film 100 may be configured to be attached to the surface of the security product by forming an adhesive layer on one surface on which the color conversion layer is formed. In this case, as the adhesive layer, an adhesive layer made of a transparent resin material may be used.

As shown in Figure 2, the surface of the security product to which the color conversion security film 100 is attached may be provided with a printing layer 200 on which predetermined characters, figures, patterns, images, etc. are printed. Alternatively, a printing layer 200 is further provided on the surface of the color conversion security film 100 to be included as one configuration of the color conversion security film 100, and may be attached to the security product in this state. In this case, an adhesive layer may be provided on the surface of the printing layer 200 .

The visual effect of the color conversion security film according to an embodiment of the present invention will be described with reference to FIG. 2 . FIG. 2 illustrates a case in which the printing layer 200 is disposed on one surface of the color conversion security film 100 on which the color conversion layer is formed. The printing layer 200 may be provided on the surface of the security product to which the color conversion security film 100 is attached, or may be provided as one configuration of the color conversion security film 100 . The print layer 200 includes a print pattern ('ABC D' in FIG. 2 ) such as characters and figures, and the print pattern is printed on one side of the print layer 200 on the side of the color conversion security film 100 or the print layer When 200 is transparent, it may be printed on the other surface of the printing layer 200 . However, in FIG. 2 , it is described on the side of the printed layer 200 for convenience.

At this time, the direction looking at the color conversion security film 100 is the direction looking from the other side of the substrate 10 on which the color conversion layer is not formed as shown in FIG. 2 (that is, the opposite direction of the printing layer 200). , the viewing angle θ in the direction perpendicular to the color conversion security film 100 is set to zero (0).

As shown in FIG. 2 , when the viewing angle θ is zero (0), that is, when the color conversion security film 100 is viewed in a vertical direction, the first region (I) and the third region ( Through III), the entire print patterns 'A' and 'C' formed on the print layer 200 are observed. In addition, in the second region (II) and the fourth region (IV), which are opaque regions, the print patterns 'B' and 'D' described in the print layer 200 are not observed because they are covered by the color conversion layer. At this time, the color conversion layer is observed as the first color.

Here, if the viewing angle θ is increased (that is, observed in an inclined direction), the viewing angle looking at the color conversion layer changes, so that the color of the color conversion layer observed in the second region (II) and the fourth region (IV) gradually decreases will change In addition, until the viewing angle reaches an angle parallel to the inclined surface of the intaglio part 12 (θ _{1 in the} drawing), only the color of the color conversion layer is changed, and the observation area of each area is maintained as it is.

When the viewing angle (θ) is further increased and the viewing angle _{becomes greater than the angle (θ 1} ) parallel to the inclined surface of the intaglio part 12, the color conversion layer along with the color change of the color conversion layer is formed in the intaglio part 12. The see-through area is started to be covered by the light, and as the viewing angle is increased, the area is gradually enlarged. Due to this, the area of the opaque region gradually increases and the observation area of the see-through region gradually decreases. That is, as shown in FIG. 2 , the characters 'A' and 'C' formed in the first region (I) and the third region (III) are covered by the color conversion layer, so that only a part thereof is observed. As such, as the viewing angle increases, the effect of changing the color of the color conversion layer, expanding the observation area, and reducing the area of the see-through area is simultaneously performed.

This effect continues until the viewing angle θ reaches the critical angle θ _{2 , and when the viewing angle is greater than or equal to the critical angle θ 2} , the observation area of the color conversion layer expands to the entire area, and the see-through area disappears, Due to this, the printed layer 200 is no longer observed. Also, the color of the color conversion layer is changed to the second color.

As such, according to the color conversion security film 100 according to the embodiment of the present invention, only with a simple structure of forming a color conversion layer on the intaglio portion 12 formed on the transparent substrate 10, color conversion that changes color depending on the viewing angle In addition to the effect, the printed layer 200 is observed through the see-through area, and the area in which the printed layer 200 is observed and the area of the area in which the color conversion layer is observed change depending on the viewing angle.

In addition, since the color conversion security film 100 has a color conversion layer formed on the inclined surface forming the intaglio portion 12 , even when rotating about an axis (z-axis) perpendicular to the color conversion security film 100 . An additional effect of the color conversion effect can be obtained. This is because, when the color conversion security film 100 is rotated on a plane about a vertical axis, the angle between the inclined surface on which the color conversion layer is formed and the viewing direction is continuously changed.

3 is a flowchart of a method for manufacturing a color conversion security film according to the present invention. 3 , the method for manufacturing a color conversion security film according to the present invention may include a substrate preparation step (step S10), a pattern forming step (step S20), and a color conversion layer forming step (step S30).

The substrate preparation step (step S10) is a step of preparing a substrate for manufacturing a color conversion security film.

The pattern forming step (step S20) is a step of forming intaglio and embossed patterns on the surface of the substrate. For this purpose, as shown in FIG. 4 , the mold 300 having the concave portion 310 and the protrusion 320 formed thereon is pressed on the surface of the substrate 10 , and the concave portion of the mold 300 is placed on the substrate 10 . The embossed part 11 and the engraved part 12 corresponding to the 310 and the protrusion 320 may be formed, respectively.

The color conversion layer forming step (step S30) is a step of forming a color conversion layer on the substrate on which the intaglio pattern is formed.

5 to 8 are flowcharts and schematic diagrams showing the color conversion layer forming step (step S30) according to the present invention, FIGS. 5 and 6 are the first embodiment, and FIGS. 7 and 8 are the second embodiment manufactured according to the present invention It is a drawing explaining the method.

5 and 6, in the first embodiment of the color conversion layer forming step (S30) according to the present invention, the light absorption layer forming step (S31), the masking forming step (S32), the dielectric layer forming step (S33) , may be formed through a reflective layer forming step ( S34 ) and a masking removal step ( S35 ).

As shown in FIG. 6 , the light absorption layer forming step (S31) may be a step of forming a light absorption layer on the entire surface of the substrate 10 including the embossed portion 11 and the intaglio portion 12, and the masking forming step (S32) may be a step of forming the masking 30 only on the surface of the embossed portion 11 . Also, the dielectric layer forming step ( S33 ) and the reflective layer forming step ( S34 ) may be steps of respectively forming a dielectric layer and a reflective layer on the entire surface of the substrate 10 . Due to this, the dielectric layer 40 and the reflective layer 50 formed on the masking 30 by the masking removal step S35 are removed, so that only the engraved portion 12 has the light absorption layer 20, the dielectric layer 40, and the reflective layer 50. ) may be formed with a stacked color conversion layer.

On the other hand, since the light absorption layer 20 is formed on the entire surface of the substrate 10 before the masking is formed, the light absorption layer 20 remains on the embossed portion 11 even after the masking is removed. Due to this, it is possible to obtain a translucent visual effect when observing the printed layer through the see-through area.

7 and 8 are flowcharts and schematic diagrams of a method for manufacturing a color conversion security film according to a second embodiment of the present invention. The second embodiment of FIGS. 7 and 8 is different from the first embodiment of FIGS. 5 and 6 only in that the masking forming step S32 is performed before the light absorbing layer forming step S31. According to this method, the light absorbing layer 20 on the embossed portion 11 is also removed by the masking removal step (S35), and thus the light absorbing layer 20 does not remain on the embossed portion 11 . For this reason, it is possible to obtain a more transparent and clear visual effect when observing the printed layer or the like through the see-through area.

In the color conversion layer forming step (step S30 ), the light absorption layer 20 , the dielectric layer 40 , and the reflective layer 50 may be deposited using a vacuum deposition method such as sputtering.

Although described with reference to the above-limited embodiments and drawings, it will be apparent to those skilled in the art that these are only embodiments, and that various modifications are possible within the scope of the technical idea of the present invention. For example, all or part of each embodiment may be selectively combined and implemented, thereby providing various visual effects not specifically described in the embodiments. Accordingly, the protection scope of the present invention should be defined by the description of the claims and their equivalents.

100: color conversion security film
10: description
11: embossed
12: intaglio
20: light absorption layer
30: masking
40: dielectric layer
50: reflective layer
200: printed layer

Claims (11)

a transparent substrate having embossed parts and engraved parts repeatedly formed on one surface;
a color conversion layer formed on the intaglio;
including,
A color conversion security film, characterized in that a transparent region and an opaque region are provided by the embossed part and the engraved part, respectively. According to claim 1,
The color conversion layer is a color conversion security film, characterized in that it comprises a structure in which a light absorption layer, a dielectric layer, and a reflective layer are laminated. According to claim 1,
A color conversion security film, characterized in that the color and observation area of the opaque region change according to the viewing angle. 4. The method of claim 3,
The color conversion security film, characterized in that the area of the see-through area changes as the observation area of the opaque area changes. According to claim 1,
The intaglio portion includes an inclined surface,
In a specific viewing angle range, only the color of the opaque region changes according to the viewing angle, and the observation area does not change. 6. The method of claim 5,
The specific viewing angle range is a color conversion security film, characterized in that from an angle perpendicular to the color conversion security film to an angle parallel to the inclined surface. 7. The method of claim 6,
The color conversion security film, characterized in that the observation area of the opaque region increases and the area of the see-through region decreases as the viewing angle is increased beyond the angle parallel to the inclined plane. According to claim 1,
The color conversion security film, characterized in that the cross-section of the intaglio portion is a V-shape or a trapezoidal shape. A security product comprising the color conversion security film of any one of claims 1 to 8. 10. The method of claim 9,
The color conversion security film is a security product, characterized in that it is adhered through an adhesive layer. 10. The method of claim 9,
A security product, characterized in that a printing layer is provided on one surface of the color conversion security film on which the color conversion layer is formed.

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