阅读说明：本技术 光学防伪元件及其制作方法 (Optical anti-counterfeiting element and manufacturing method thereof ) 是由 *** 朱军 张巍巍 孙凯 于 2019-03-29 设计创作，主要内容包括：本发明公开了一种光学防伪元件及其制作方法,属于光学防伪技术领域。所述光学防伪元件包括：起伏结构层,所述起伏结构层具有第一区域、第二区域和第三区域；所述第一区域具有第一微结构；所述第二区域具有第二微结构；所述第三区域为无结构的平坦区域；所述第二微结构的比体积大于所述第一微结构的比体积；所述第一区域和所述第三区域均具有重叠的反射层、介电层和吸收层,且所述第二区域不具有反射层；位于所述第一区域的介电层远离起伏结构层一侧的表面形貌与起伏结构层的表面形貌明显不同。光学防伪元件一侧反射观察时,第一区域具有较弱的或者不具有干涉光变效果,第三区域具有明显的干涉光变效果,透视观察时,第二区域具有镂空效果。(The invention discloses an optical anti-counterfeiting element and a manufacturing method thereof, belonging to the technical field of optical anti-counterfeiting. The optical security element comprises: a relief structure layer having a first region, a second region, and a third region; the first region has a first microstructure; the second region has a second microstructure; the third area is a flat area without a structure; the specific volume of the second microstructure is larger than that of the first microstructure; the first region and the third region each have an overlapping reflective layer, dielectric layer, and absorptive layer, and the second region has no reflective layer; the surface appearance of the dielectric layer in the first region, which is far away from the relief structure layer, is obviously different from that of the relief structure layer. When one side of the optical anti-counterfeiting element is observed in a reflecting mode, the first area has a weak or no interference light variation effect, the third area has an obvious interference light variation effect, and when the optical anti-counterfeiting element is observed in a perspective mode, the second area has a hollow effect.)

1. An optical security element, comprising:

a relief structure layer having a first region, a second region, and a third region;

the first region has a first microstructure;

the second region has a second microstructure;

the third area is a flat area without a structure;

wherein the specific volume of the second microstructure is greater than the specific volume of the first microstructure;

wherein the first and third regions each have an overlapping reflective layer, dielectric layer and absorptive layer, and the second region has no reflective layer;

and the surface appearance of the dielectric layer in the first region, which is far away from the relief structure layer, is obviously different from that of the relief structure layer.

2. An optical security element according to claim 1,

the first microstructure is one of a periodic structure and a non-periodic structure, or a structure of a combination of the periodic structure and the non-periodic structure;

the cross section structure of the first microstructure along the extension direction is as follows:

one of a sinusoidal structure, a rectangular grating structure, a semicircular structure and a blazed grating structure, or a structure formed by combining at least any two of the sinusoidal structure, the rectangular grating structure, the semicircular structure and the blazed grating structure.

3. An optical security element according to claim 1,

the specific volume range of the first microstructure is more than 0.05um³/um²And less than 0.5um³/um²。

4. An optical security element according to claim 3,

the specific volume range of the first microstructure is more than 0.1um³/um²And less than 0.3um³/um²。

5. An optical security element according to claim 1,

the second microstructure is one of a periodic structure and a non-periodic structure, or a structure of a combination of the periodic structure and the non-periodic structure;

the cross section structure of the second microstructure along the extension direction is as follows:

the grating structure comprises a sinusoidal structure, a rectangular grating structure, a semicircular structure, a trapezoidal structure and a blazed grating structure, or a structure formed by combining at least any two of the sinusoidal structure, the rectangular grating structure, the semicircular structure, the trapezoidal structure and the blazed grating structure.

6. An optical security element according to claim 1,

the specific volume range of the second microstructure is more than 0.1um³/um²And less than 1um³/um²。

7. An optical security element according to claim 6,

the specific volume range of the second microstructure is more than 0.2um³/um²And less than 0.5um³/um²。

8. An optical security element according to claim 1,

the material of the reflecting layer comprises:

one metal of aluminum, silver, copper, tin, chromium, nickel and titanium, or an alloy formed by combining at least any two metals of aluminum, silver, copper, tin, chromium, nickel and titanium;

the dielectric layer is formed by printing;

the main resin of the dielectric layer includes:

one resin of polyurethane, acrylic acid and polyester, or a polymer formed by combining at least any two resins of polyurethane, acrylic acid and polyester;

the material of the absorption layer comprises:

one metal of nickel, chromium, aluminum, silver, copper, tin and titanium, or an alloy formed by combining at least any two metals of nickel, chromium, aluminum, silver, copper, tin and titanium.

9. An optical security element according to claim 1,

the reflective layer is adjacent to the relief structure layer.

10. An optical security element according to claim 9,

the second region is free of a dielectric layer and an absorber layer.

11. An optical security element according to claim 1,

the absorbing layer is adjacent to the relief structure layer.

12. An optical security element according to claim 1,

the second region has a dielectric layer and an absorber layer.

13. A method for producing an optical security element, the method comprising:

s1) forming a relief structure layer having a first region, a second region and a third region, the first region having a first microstructure, the second region having a second microstructure, the second microstructure having a specific volume greater than that of the first microstructure and the third region being a flat region without a structure;

s2) sequentially forming a reflective layer, a dielectric layer and an absorption layer on the relief structure layer, wherein the reflective layer is formed by vapor deposition, the dielectric layer is formed by printing and the absorption layer is formed by vapor deposition;

s3) placing the semi-finished product of the step S2) in a corrosive atmosphere capable of reacting with the material of the reflective layer until the reflective layer of the second area is completely or partially removed.

14. The method according to claim 13, wherein the step S3) further includes, during the process of removing the whole or part of the reflective layer in the second area:

the dielectric layer and the absorber layer of the second region are also removed, either completely or partially.

15. A method for producing an optical security element, the method comprising:

s1) forming a relief structure layer having a first region, a second region and a third region, the first region having a first microstructure, the second region having a second microstructure, the second microstructure having a specific volume greater than that of the first microstructure and the third region being a flat region without a structure;

s2) sequentially forming an absorption layer, a dielectric layer and a reflection layer on the relief structure layer, wherein the reflection layer is formed by vapor deposition, the dielectric layer is formed by printing and the absorption layer is formed by vapor deposition;

s3) after the reflection layer is formed, a printing procedure is applied to form a protective layer according to different thickness modes, wherein the different thickness modes are modes that the minimum thickness of the protective layer of the first area is obviously larger than that of the protective layer of the second area;

s4) placing the semi-finished product of the step S3) in a corrosive atmosphere capable of reacting with the material of the reflecting layer for antireflection until the reflecting layer of the second area is completely or partially removed.

16. The method according to claim 15, wherein the step S4) further includes, during the process of removing the whole or part of the reflective layer in the second area:

the reflective layer of the second region is removed, and neither the dielectric layer nor the absorbing layer is removed.

17. The method of manufacturing according to any one of claims 13 to 16, further comprising:

and continuing to apply an inorganic or organic coating or a coating process to realize other optical anti-counterfeiting functions or auxiliary functions.

Technical Field

The invention relates to the technical field of optical anti-counterfeiting, in particular to an optical anti-counterfeiting element and a manufacturing method of the optical anti-counterfeiting element.

Background

In order to prevent counterfeiting by means of scanning, copying and the like, optical anti-counterfeiting technology is widely adopted in various high-security or high-value-added printed matters such as bank notes, credit cards, passports, securities, product packages and the like, and a very good effect is achieved.

In various optical anti-counterfeiting technologies, optical effects formed by microstructures, such as diffraction effects and non-diffraction effects, are widely applied due to good compatibility with image design and obvious dynamic effect. Microstructure optical anti-counterfeiting technology to increase the brightness of an image, a metal reflective layer, such as aluminum, is generally used. Among them, the holographic technique, which is the most widely used optical anti-counterfeit technique for optical films, is an optical technique developed by using the diffraction effect of optical microstructures. The fifth set 1999 edition of the security thread of 5 yuan, 10 yuan, 20 yuan, 50 yuan and 100 yuan RMB adopts the holographic technology, and when the RMB ticket face is shaken, a shiny holographic ticket face digital image can be observed. In addition, the multilayer interference light variation technology is receiving more and more attention because it shows strong optical color variation effect under different viewing angles. The multilayer interference light variation technology generally adopts a vapor deposition method to realize evaporation of a reflecting layer, a dielectric layer and an absorbing layer. The reflecting layer, the medium layer and the absorbing layer form a basic unit of the interference light variable coating. The reflective layer is generally made of a thick material and has high reflectivity, while the absorptive layer is generally made of a thin material and has a translucent characteristic. The dielectric layer is made of transparent material, and if the thickness meets a certain condition, light rays can interfere in a Fabry-Perot cavity formed by the parallel reflecting layer and the absorbing layer. The interference light variable coating layer shows different colors at different angles when viewed from the absorption layer side. The fifth set of 2015 edition 100 yuan RMB security thread adopts multilayer interference light variation technology, and is seen magenta on the front and green on the slant. If the holographic and non-diffractive optical microstructure anti-counterfeiting technology and the multilayer interference light variation technology are integrated into the same product, the holographic and non-diffractive dynamic effect and the light variation effect of the multilayer coating can be effectively exerted, and the anti-counterfeiting effect can be enhanced to a certain extent. However, if a multilayer interference coating is directly deposited on the optical microstructure, the optical effect exhibited by the optical microstructure and the interference light variation effect are mutually weakened.

Patent application CN200980104829.3 proposes that the preparation of the optical anti-counterfeiting product with the integration of the optical characteristics of multilayer interference light variation and high-brightness reflection microstructures (including diffraction microstructures and non-diffraction microstructures) is realized through a local printing and hollowing process, namely, a part of the area has the optical characteristics of multilayer interference light variation, a part of the area has the optical characteristics of high-brightness reflection microstructures, and other areas have hollowing effects. However, the precision of the local hollow-out area in the patent application depends on the printing precision, and the printing precision is generally above 100um, which limits the application in high-end anti-counterfeiting optical products to a certain extent.

Therefore, the anti-counterfeiting optical element has the mutually independent optical microstructure (such as holography, non-diffraction and the like) anti-counterfeiting characteristics and multilayer interference light variable optical characteristics, the hollow area is high-precision relative to the optical microstructure image area, and even can be used as an optical anti-counterfeiting element with zero error positioning, and the optical anti-counterfeiting optical element has important significance for researching the characteristic positioning of the optical anti-counterfeiting element.

Disclosure of Invention

The invention aims to provide an optical anti-counterfeiting element and a manufacturing method thereof, wherein the optical anti-counterfeiting element comprises mutually independent optical microstructure (such as holography, non-diffraction and the like) anti-counterfeiting characteristics and multilayer interference light variation optical characteristics, and is provided with a hollow area strictly positioned with an optical microstructure image.

In order to achieve the above object, an embodiment of the present invention provides an optical security element, including: a relief structure layer having a first region, a second region, and a third region; the first region has a first microstructure; the second region has a second microstructure; the third area is a flat area without a structure; wherein the specific volume of the second microstructure is greater than the specific volume of the first microstructure; wherein the first and third regions each have an overlapping reflective layer, dielectric layer and absorptive layer, and the second region has no reflective layer; and the surface appearance of the dielectric layer in the first region, which is far away from the relief structure layer, is obviously different from that of the relief structure layer. It should be noted that the first region, the second region and the third region are not only considered to be a fixed sequence on the relief structure layer, but may also be any other sequence of the second region, the first region and the third region. When the optical anti-counterfeiting element is observed in a reflection mode, the first area presents a specific image presented by the first microstructure, and has no or weak interference light variation effect, the third area has an obvious interference light variation effect, and when the optical anti-counterfeiting element is observed in a perspective mode, the second area has a light-transmitting hollow effect and is strictly positioned with the image presented by the first area. The specific volume of the microstructure refers to the ratio of the volume of liquid just filled in the microstructure to the projection area of the optical anti-counterfeiting element when the optical anti-counterfeiting element is placed horizontally, and the unit of the specific volume is um³/um². The difference between the microstructure of the second region and the microstructure of the first region is set for the requirement of hollowing, namely the microstructure with small specific volumeThe structured reflective layer is retained and the reflective layer of the microstructure over a large specific volume is removed. This problem will be discussed further in the detailed description section.

Optionally, the first microstructure is one of a periodic structure and a non-periodic structure, or a structure in which a periodic structure and a non-periodic structure are combined;

the cross section structure of the first microstructure along the extension direction is as follows:

one of a sinusoidal structure, a rectangular grating structure, a semicircular structure and a blazed grating structure, or a structure formed by combining at least any two of the sinusoidal structure, the rectangular grating structure, the semicircular structure and the blazed grating structure.

Optionally, the specific volume range of the first microstructure is greater than 0.05um³/um²And less than 0.5um³/um²。

Preferably, the specific volume range of the first microstructure is preferably more than 0.1um³/um²And less than 0.3um³/um²。

Optionally, the second microstructure is one of a periodic structure and a non-periodic structure, or a structure in which a periodic structure and a non-periodic structure are combined;

the cross section structure of the second microstructure along the extension direction is as follows:

the grating structure comprises a sinusoidal structure, a rectangular grating structure, a semicircular structure, a trapezoidal structure and a blazed grating structure, or a structure formed by combining at least any two of the sinusoidal structure, the rectangular grating structure, the semicircular structure, the trapezoidal structure and the blazed grating structure.

Optionally, the specific volume range of the second microstructure is greater than 0.1um³/um²And less than 1um³/um²。

Preferably, the specific volume range of the second microstructure is preferably greater than 0.2um³/um²And less than 0.5um³/um²。

Optionally, the material of the reflective layer includes:

one metal of aluminum, silver, copper, tin, chromium, nickel and titanium, or an alloy formed by combining at least any two metals of aluminum, silver, copper, tin, chromium, nickel and titanium;

the dielectric layer is formed by printing;

the main resin of the dielectric layer includes:

one resin of polyurethane, acrylic acid and polyester, or a polymer formed by combining at least any two resins of polyurethane, acrylic acid and polyester;

the material of the absorption layer comprises:

one metal of nickel, chromium, aluminum, silver, copper, tin and titanium, or an alloy formed by combining at least any two metals of nickel, chromium, aluminum, silver, copper, tin and titanium.

Optionally, the reflective layer is adjacent to the relief structure layer. Here, the order of the layers is further set, and if the relief structure layer is selected as a reference bottom, the relief structure layer, the reflective layer, the dielectric layer, and the absorption layer are arranged in order from bottom to top.

Optionally, the second region is free of a reflective layer, a dielectric layer, and an absorbing layer.

Optionally, the absorbing layer is adjacent to the relief structure layer. Here, the order of the layers is further set, and if the relief structure layer is selected as a reference bottom, the relief structure layer, the absorption layer, the dielectric layer and the reflection layer are arranged in sequence from bottom to top.

Optionally, the second region has a dielectric layer and an absorber layer.

The embodiment of the invention provides a manufacturing method of an optical anti-counterfeiting element, which comprises the following steps:

s1) forming a relief structure layer having a first region, a second region and a third region, the first region having a first microstructure, the second region having a second microstructure, the second microstructure having a specific volume greater than that of the first microstructure and the third region being a flat region without a structure;

s2) sequentially forming a reflective layer, a dielectric layer and an absorption layer on the relief structure layer, wherein the reflective layer is formed by vapor deposition, the dielectric layer is formed by printing and the absorption layer is formed by vapor deposition;

s3) placing the semi-finished product of the step S2) in a corrosive atmosphere capable of reacting with the material of the reflective layer until the reflective layer of the second area is completely or partially removed.

Specifically, step S3) further includes, in the process of removing all or part of the reflective layer in the second area:

the dielectric layer and the absorber layer of the second region are also removed, either completely or partially.

The embodiment of the invention also provides a manufacturing method of the optical anti-counterfeiting element, which comprises the following steps:

s1) forming a relief structure layer having a first region, a second region and a third region, the first region having a first microstructure, the second region having a second microstructure, the second microstructure having a specific volume greater than that of the first microstructure and the third region being a flat region without a structure;

s2) sequentially forming an absorption layer, a dielectric layer and a reflection layer on the relief structure layer, wherein the reflection layer is formed by vapor deposition, the dielectric layer is formed by printing and the absorption layer is formed by vapor deposition;

s3) after the reflection layer is formed, a printing procedure is applied to form a protective layer according to different thickness modes, wherein the different thickness modes are modes that the minimum thickness of the protective layer of the first area is obviously larger than that of the protective layer of the second area;

s4) placing the semi-finished product of the step S3) in a corrosive atmosphere capable of reacting with the material of the reflecting layer for antireflection until the reflecting layer of the second area is completely or partially removed.

Specifically, step S4) further includes, in the process of removing all or part of the reflective layer in the second area:

the reflective layer of the second region is removed, and neither the dielectric layer nor the absorbing layer is removed.

Specifically, still include:

and continuing to apply an inorganic or organic coating or a coating process to realize other optical anti-counterfeiting functions or auxiliary functions.

Through the content, the invention realizes the relief structure layer with asymmetric and surface heterogeneous characteristics, and the relief structure layer is used for manufacturing the relief structure layer with a plurality of relatively independent local areas, particularly realizes the local profile heterogeneous asymmetry of the optical anti-counterfeiting element through at least the area with the multilayer interference optical variable characteristics, and the hollow area formed by the plurality of relatively independent local areas of the optical anti-counterfeiting element has high local image detail precision and clear transmission imaging.

Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:

FIG. 1 is a top view of an optical security element according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of an optical security element according to an embodiment of the present invention having a first surface microstructure relief structure layer along the pattern "X-X";

FIG. 3 is a cross-sectional view of an optical security element according to an embodiment of the present invention having a second surface microstructure relief structure layer along the pattern "X-X";

FIG. 4 is a cross-sectional view of a semi-finished product after forming a relief structure layer having a first region, a second region, and a third region according to a first embodiment of the surface microstructure of the present invention;

FIG. 5 is a cross-sectional view of a first embodiment of a surface microstructure of the present invention after forming a relief structure layer having a reflective layer, a dielectric layer, and an absorber layer;

FIG. 6 is a cross-sectional view of a first surface microstructure embodiment of the invention after etching of the reflective layer in the second region of the relief structure layer;

FIG. 7 is a cross-sectional view of a semi-finished product after formation of other functional coatings according to a first embodiment of the surface microstructure of the present invention;

FIG. 8 is a cross-sectional view of a semi-finished product after forming a relief structure layer having a first region, a second region, and a third region according to a second embodiment of the present invention;

FIG. 9 is a cross-sectional view of a second embodiment of a surface microstructure of the present invention after forming a relief structure layer having a reflective layer, a dielectric layer, and an absorber layer;

FIG. 10 is a cross-sectional view of a semi-finished product after a protective layer is applied to a relief structure layer in accordance with a second embodiment of the surface microstructure of the present invention;

FIG. 11 is a cross-sectional view of a second surface microstructure embodiment of the present invention after etching of the reflective layer in the second region of the relief structure layer;

FIG. 12 is a cross-sectional view of a second surface microstructure embodiment of the invention after formation of additional functional coatings.

Description of the reference numerals

A image area and B hollow area

C interference light variable area 1 base material

2 relief structure layer 3 interference optical changing layer

31 reflective layer 32 dielectric layer

33 absorbing layer 4 other functional coating

5 protective layer

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration and explanation only, not limitation.