WO2017131447A1

WO2017131447A1 - Method for producing microlens-based security image film having micronic thickness

Info

Publication number: WO2017131447A1
Application number: PCT/KR2017/000905
Authority: WO
Inventors: 김종엽
Original assignee: 주식회사 비주얼넷; 주식회사 우리옵토
Priority date: 2016-01-29
Filing date: 2017-01-25
Publication date: 2017-08-03
Also published as: KR101644830B1

Abstract

Disclosed is a method for producing a microlens-based security image film having a micronic thickness. The stereoscopic image film production method according to the present invention comprises the steps of: (a) applying a first ultraviolet-curable resin (21) onto a substrate (20); (b) positioning the pattern surface of a first mold (22) on the first ultraviolet-curable resin (21) applied in step (a), subjecting same to pressurization and ultraviolet radiation, and thereby transferring a microlens pattern (220) to the upper surface of the first ultraviolet-curable resin (21); (c) applying a second ultraviolet-curable resin (23) onto the first ultraviolet-curable resin (21); and (d) transferring the pattern surface of a second mold (26), on which a security image pattern (260) is formed, to the upper surface of the second ultraviolet-curable resin (23). The present invention enables production of security image pattern films having various forms and specifications, since the refractive index of an ultraviolet-curable resin on each layer of a multi-layered optical film can be freely selected; can obtain a more vivid pattern as well as being thin and having a high yield by not using a substrate in a base film form and not requiring the overturning of an intermediate product; and can be formed so thin as to be attached to a target product by means of an automatic labeling apparatus.

Description

Micro lens based security image film manufacturing method with micron unit thickness

The present invention relates to a method for manufacturing a microlens-based security image film, and more particularly, to a microlens-based security image film that can be formed into a thin thickness that can be attached to a target product using an auto labeling device. It relates to a manufacturing method.

A three-dimensional film manufacturing method has been developed and used that the lower pattern is enlarged through a microlens such as a lenticular lens made of transparent plastic, so that the naked eye can be identified as a three-dimensional image. Such a three-dimensional film manufacturing method is applied to a label or various security projects for displaying the genuine, and is manufactured in a micro-optic security film method using a high-precision micro mold. In order to form a three-dimensional image, a set of transparent plastic lenticular lenses is precisely superimposed on a printing surface, and the three-dimensional image appears by the action of the lenticular lens.

If the images of the left and right eyes are alternately printed under the plastic lens, which is a lenticular lens, each image is shown by the difference in the direction of the left and right eyes, thereby obtaining a three-dimensional effect, which is called a lenticular stereo system. This is a special camera (binocular camera) that photographs a subject with a perspective, and the manuscript is offset printed on a flat panel of 300-line screen.

However, according to the conventional manufacturing method, in order for the lower pattern to be enlarged through the microlenses and the naked eye can be identified by the three-dimensional image, the thickness of the three-dimensional film is considerable, so that an apparatus which automatically attaches to the actual product such as an auto labeler can be used. There is no problem.

Meanwhile, Korean Patent Nos. 10-1341072 and 10-1384717 disclose a three-dimensional lens sheet including a plurality of nanostructures, respectively, and a label for authenticity verification using a plurality of nanostructures and three-dimensional lenses. According to the registered patent, a three-dimensional lens layer including a lenticular lens in which a plurality of semi-circular convex lenses are arranged in parallel, or a micro lens in which a plurality of semi-circular convex lenses are arranged in series, and a lower portion of the three-dimensional lens layer. An identification mark forming unit including a focal length layer provided and an image forming layer disposed below the focal length layer; And a coupling member for allowing the identification mark forming portion to be coupled with the corresponding article, wherein the image forming layer includes a plurality of nano structures periodically and regularly arranged to protrude at intervals and heights of 50 to 200 nanometers. And between the nanostructure and the focal length layer, the nanostructure and the focal length layer are composed of a medium having a different refractive index.

However, in order to manufacture a conventional three-dimensional lens sheet or authenticity label as described above is formed in the form of a base layer film between the lens layer and the image pattern layer, such a base layer film is formed of an optical layer such as a lens layer and an image pattern layer The thickness and refractive index of the lens are limited, and the lens layer, the base layer film, and the base layer film and the image pattern layer cause a deformation of the image due to the difference in refractive index, which is not clear and blurry.

In addition, according to the prior art as described above, there is a limitation that the overall thickness becomes thick during the formation of each layer, and the intermediate process material is formed during the manufacturing process because the lens layer and the image pattern layer should be formed on the top and bottom surfaces of the base layer film. There is a problem in that the manufacturing process is difficult and product yield is also poor because it must be turned over.

The present invention has been invented to solve the above problems, the technical problem to be achieved by the present invention is to freely select the refractive index of the ultraviolet curing resin of each layer in the optical film of the multi-layer structure to provide a security image pattern film of various forms and specifications It is possible to manufacture, it is not necessary to invert the intermediate process without using the base film type base material, so that the thickness is thin and the yield is high, as well as a clearer pattern can be obtained, and it is attached to the target product using the auto labeling device. It is to provide a micro lens-based security image film manufacturing method that can be formed to a thin thickness as possible.

Micro lens-based security image film manufacturing method having a micron unit thickness according to the present invention for achieving the above object,

(a) applying the first ultraviolet curable resin 21 on the substrate 20;

(b) placing the patterned surface of the first mold 22 on which the first microlens pattern 220 is formed, on the first ultraviolet curing resin 21 coated in step (a), and pressing and irradiating ultraviolet rays. Transferring the microlens pattern 220 to an upper surface of the first ultraviolet curing resin 21;

(c) applying the second ultraviolet cured resin 23 on the microlens pattern 220 of the first ultraviolet cured resin 21 transferred and cured by the step (b). Wow;

(d) transferring the pattern surface of the second mold 26 having the security image pattern 260 formed on the upper surface of the second ultraviolet curing resin 23 coated by the step (c); And

(e) The printing material 27 including colored nanopowder and ultraviolet curable resin in the recessed portion of the security image pattern 260 formed on the second ultraviolet curing resin 23 so that the security image pattern 260 is visible. Impregnating and UV curing, or coating a reflective layer on the entire security image pattern 260 formed on the second ultraviolet curing resin 23 or coating a material having a refractive index difference of at least a certain amount. do.

In addition, the manufacturing method, before the step (a),

(a-1) forming a release layer on the substrate 20;

The step (a) may be a step of applying a liquid first ultraviolet curable resin 21 on the release layer.

In addition, the manufacturing method may further include forming an additional pattern layer on the pattern layer formed by the step (e ') (e') after the step (e).

In addition, it is more preferable that the refractive index difference between the 1st ultraviolet curing resin 21 and the 2nd ultraviolet curing resin 23 is 0.125-0.3.

In addition, the manufacturing method is applied between the step (c) and the step (d) and (c ') of the second ultraviolet curable resin 23 two times and between the lens layer and the security image pattern layer More preferably, the method further includes forming the breakdown layer 212 by partially coating the transparent silicon.

According to the present invention, the refractive index of the ultraviolet curable resin of each layer can be freely selected from the optical film of the multilayer structure composed of the first lens layer and the composite layer, so that it is possible to manufacture security image pattern films of various shapes and specifications. By properly designing the refractive indices of the 1 ultraviolet curing resin 21 and the 2nd ultraviolet curing resin 23 and the shape of the lens, it is possible to deepen the depth of focus and to display the inside of the product in three dimensions even with a relatively thin thickness. It is possible to represent a security image, which is relatively remarkably clear compared to that produced by the prior art.

In addition, in the prior art using a base film-type substrate, since the lens layer is formed on one surface of the substrate, the security image pattern layer should be formed on the other side of the substrate, resulting in increased product defects and a lower yield. In addition, it is difficult to obtain a clear pattern. However, the microlens-based security image film manufacturing method having a micron unit thickness according to the present invention as described above is made by sequential lamination on only one surface of the surface substrate. Therefore, it is not necessary to turn over the intermediate process, the yield is higher than the conventional method, and a clearer pattern can be obtained.

In addition, according to the present invention, in particular, when the release layer is applied, the surface substrate serves only to support the first lens layer and the composite layer to be stacked thereon, and the surface substrate can be removed thereafter. Because of this, a remarkably thin security image pattern label can be manufactured and formed to a thickness thin enough to be attached to a target product using an auto labeling device.

1 is a flow chart showing the main process of the microlens-based security image film manufacturing method having a micron unit thickness according to a preferred embodiment of the present invention,

FIG. 2 is a view for explaining a process of forming a first lens layer by UV molding through steps S101 to S104 in the flowchart of FIG. 1;

3 is a view for explaining a process of forming a composite layer of a second lens layer and a focal length layer through steps S106 to S110 in the flowchart of FIG. 1;

4 is a view for explaining the structure of the intermediate process step S112 is completed in the flow chart of FIG.

5 is a view for explaining a pressure roll that can be applied to coat the ultraviolet curing resin and its adjustable coating conditions in the production method according to the invention,

6 is a microlens-based security image film manufactured according to another embodiment of the method for manufacturing a microlens-based security image film having a micron unit thickness according to the present invention, having a release layer on a surface substrate to separate the surface substrate. For explaining that it is possible to express the color by multi-layer printing,

7 is a cross-sectional view for explaining the effect of the embodiment having a fracture layer and the surface substrate is removed by the release layer separation, and

FIG. 8 is a sectional view for explaining the effect of the breaking layer formed by step S107 in the flowchart of FIG. 1; FIG.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a flowchart illustrating a main process of a method for manufacturing a microlens-based security image film having a micron unit thickness according to a preferred embodiment of the present invention. Referring to FIG. 1, a method of manufacturing a microlens-based security image film having a micron unit thickness according to the present invention may include a substrate such as PC (poly-carbonate) or PET (poly-ethylene) as shown in FIG. 2. The first mold on which the mold release layer 202 is selectively coated (step S100) and then the first ultraviolet curable resin 21 is applied (step S101) as necessary on the microlens pattern 220. The pattern surface of (22) is placed on the first ultraviolet curing resin 21 coated in the step S100, pressurized and irradiated with ultraviolet rays (step S102). Transfer of the microlens pattern 220 is finished on the upper surface of the first ultraviolet curing resin 21 by ultraviolet curing (step S104). As a result, the first lens layer is formed on the surface substrate 20 by UV molding.

3 is a view illustrating a process of forming a composite layer of a second lens layer and a focal length layer through steps S106 to S110 in the flowchart of FIG. 1. Referring to FIG. 3, the second ultraviolet curing resin 23 is coated on the microlens pattern 220 (step S106), and the pattern surface of the second mold 26 having the security image pattern 260 is formed. Located on the upper surface of the second ultraviolet curing resin 23 applied in the step (S106) and pressurized and irradiated with ultraviolet (step S108).

When the microlens pattern 240 is transferred to the upper surface of the second ultraviolet curing resin 23 by UV curing (step S110), the cured second ultraviolet curing resin 23 includes a security image pattern 220. The refractive index difference between the first ultraviolet curable resin 21 and the second ultraviolet curable resin 23 is formed as a composite layer that acts as a second lens layer and serves as a focal length layer.

Next, the impregnation of the printing material 27 including the colored nano-powder and the ultraviolet curable resin in the concave portion, which is the three-dimensional image pattern 260 formed on the third ultraviolet curable resin 25, or impregnation for ultraviolet curing or more The security image is formed by further coating the optical layer having the refractive index difference or by coating the reflective layer (step S112). 4 shows an example of the intermediate workpiece structure in which step S112 is completed. Referring to FIG. 4, it should be noted that a release layer 202 is provided on the surface substrate 20 to be removed after forming the lens layers and the focal length layer.

*

In the manufacturing method according to the present invention, the thickness of the transparent substrate can be freely selected within 3 to 30 microns. For example, when removing the surface substrate including the release layer, it may be freely selected from 3 to 30 microns, and when the surface substrate is not removed, a surface substrate having a thickness of up to 3 microns may also be used.

The stereoscopic image pattern 260 is visually observed through the microlenses made on the bottom of the transparent substrate, and the thickness of the product is virtually determined by the second ultraviolet curing resin layer 23 serving as the substrate 20 and the focal length layer. The thickness of the second ultraviolet curable resin 23 in the present invention can be implemented to about 60 to 70 microns and may be implemented in less than 90 microns.

5 is a view illustrating a pressure roll that can be applied to coat an ultraviolet curable resin and its adjustable coating conditions in the manufacturing method according to the present invention. In the present invention, the thickness of the second ultraviolet curable resin 23 may be about 60 to 70 microns, and the third ultraviolet curable resin may be less than 20 microns, which is illustrated in FIG. 5. It is possible by appropriately adjusting the thickness T, the pressurization pressure P of the press roll, the rotational speed V, and the viscosity V of the ultraviolet curable resin.

6 is a microlens-based security image film manufactured according to another embodiment of a method for manufacturing a microlens-based security image film having a micron unit thickness according to the present invention, having a release layer on a surface substrate to separate a surface substrate. The figure for explaining that it is possible and color representation by multilayer printing is shown.

Referring to FIG. 6, when the release layer is applied, the surface substrate 20 serves only to support the first lens layer, the second lens layer, the third lens layer, and the composite layer to be stacked thereon. After completing the post process (step S120) such that the surface substrate 20 can be separated and removed (step S122), the product label thickness after removing the surface substrate can be implemented to less than 90 microns. Therefore, the manufacturing method according to the present invention is to be able to manufacture a product label having a security image pattern to a thickness thin enough to be automatically attached to the target product using the auto labeling device.

Referring to FIG. 6, on the security image pattern 260, the multi-layer printing may be performed by further coating the fourth ultraviolet curable resin 28, forming the security image pattern 290, and filling the printing material 29. It is possible. Since the fourth ultraviolet curable resin 28 is less than 20 microns and can be positioned within the depth of focus range, the security image pattern 260 and the security image pattern 290 are represented as being located at the same focus, thereby enabling color implementation.

7 is a cross-sectional view for explaining the operation and effect of the embodiment having a fracture layer and the surface substrate is removed by the release layer separation. Referring to FIG. 7, in this embodiment, as described with reference to FIG. 4, a breakdown layer 212 is provided between the lens layer and the security image pattern layer, which are layers formed by the second UV curable resin 23. The breakdown layer 212 is formed by preferably partially coating transparent silicon between step S106 and step S108, for which the second ultraviolet curing resin 23 is applied and cured twice. And is formed between them. Since the destructive layer 212 is made of, for example, transparent silicon, the security image pattern is displayed. However, since the destructive layer 212 is not large, the destructive layer 212 may adversely affect the optically clear image.

*

In the case of the prior art, since the substrate is mass-produced in the form of a base film, not only the refractive index can not be freely selected, but also the selection of its thickness is considerably limited. As a result, in the prior art, the thickness of the entire label becomes relatively thick, which makes it impossible to attach using the autolabeler.

However, the method of manufacturing a microlens-based security image film having a micron unit thickness according to the present invention is based on UV molding as in the formation of the first lens layer without using a base film-type base material for the layer corresponding to the focal length layer. As a result, a composite layer serving as the second lens layer and the focal length layer is laminated. At this time, it should be noted that the base film type substrate is not used by stacking a composite layer that serves as the second lens layer and the focal length layer. Since the composite layer serving as the focal length layer is made of the same ultraviolet curable resin as the first lens layer and the security image pattern layer, the optical characteristics such as refractive index are the same, so that a clear image can be obtained without unnecessary optical loss.

Further, according to the present invention, the refractive index of the ultraviolet curable resin can be selected relatively easily, so that the focal length layer can be freely designed to reduce the thickness of the focal length layer. As a result, the thickness of the product label is 90 micron except for the surface substrate. It is possible to manufacture below. In particular, when the release layer is provided, it is possible to remove the surface substrate for supporting the lens layers and the focal length layer to be formed, so that it is possible to manufacture even thinner, for example, less than 50 microns.

If the difference between the refractive indices of the first ultraviolet curable resin 21 and the second ultraviolet curable resin 23 is less than 0.125, the difference in refractive index is insignificant and the imaging is blurred due to insufficient lens action. Too much magnification reduces sharpness. Therefore, the refractive index difference between the first ultraviolet curable resin 21 and the second ultraviolet curable resin 23 is preferably set to 0.125 to 0.3.

FIG. 8 is a cross-sectional view illustrating the effect of the breaking layer formed by step S107 in the flowchart of FIG. 1. Referring to FIG. 8, an attempt to separate the security image film according to the present invention from a product, such as when immersed in chemicals or hot water, separates the lens layer and the security image pattern layer by a destructive layer 212 and is very thin, less than 100 microns. The lens layer is easily irreversibly destroyed, completely losing its function as a security image pattern film.

As described above, when the base film-type substrate is used as the focal length layer as in the prior art, the thickness of the security image film is not only thickened by the thickness of the base film itself, but also suitable for the refractive index and thickness of the substrate. Since the refractive index and thickness of the layer must be determined, the manufacturing process is limited, and various patterns cannot be freely produced, and the security image pattern is not clearly displayed. However, according to the present invention, it is possible to freely select the refractive index of the ultraviolet curable resin of each layer in the optical film having a multi-layer structure consisting of the first lens layer and the composite layer, so that it is possible to manufacture security image pattern films of various shapes and specifications. By properly designing the shapes of the first ultraviolet curable resin 21, the second ultraviolet curable resin 23 and the lens, it is possible to deepen the depth of focus. It is possible to express, and the security image is relatively remarkably clear compared to that produced by the prior art.

In addition, according to the present invention, in particular, when the release layer is applied, the surface substrate serves only to support the first lens layer, the second lens layer, the third lens layer, and the composite layer to be stacked thereon, and then Since the surface substrate can be separated and removed, a remarkably thin security image pattern label can be produced and formed to a thickness thin enough to be attached to a target product using an auto labeling device.

Claims

(a) applying the first ultraviolet curable resin 21 on the substrate 20;

(b) placing the patterned surface of the first mold 22 on which the first microlens pattern 220 is formed, on the first ultraviolet curing resin 21 coated in step (a), and pressing and irradiating ultraviolet rays. Transferring the microlens pattern 220 to an upper surface of the first ultraviolet curing resin 21;

(c) applying the second ultraviolet cured resin 23 on the microlens pattern 220 of the first ultraviolet cured resin 21 transferred and cured by the step (b). ;

(d) transferring the pattern surface of the second mold 26 having the security image pattern 260 formed on the upper surface of the second ultraviolet curing resin 23 coated by the step (c); And

(e) The printing material 27 including colored nanopowder and ultraviolet curable resin in the recessed portion of the security image pattern 260 formed on the second ultraviolet curing resin 23 so that the security image pattern 260 is visible. Impregnating and UV curing, or coating a reflective layer on the entire security image pattern 260 formed on the second ultraviolet curing resin 23 or coating a material having a refractive index difference of at least a certain amount.

Between steps (c) and (d),

(c ') forming the destruction layer 212 by applying and curing the second ultraviolet curable resin 23 twice and partially coating transparent silicon between the lens layer and the security image pattern layer; Microlens-based security image film manufacturing method having a micron unit thickness, comprising a.
The method of claim 1,

Before step (a) above,

(a-1) forming a release layer on the substrate 20;

The step (a) is a step of applying a liquid first ultraviolet curable resin (21) on the release layer; microlens-based security image film manufacturing method having a unit thickness, characterized in that the.
The method of claim 1,

After step (e),

(e ') forming an additional pattern layer on the pattern layer formed by the step (e); microlens-based security image film manufacturing method having a micron unit thickness, characterized in that it further comprises.
The method of claim 1,

The difference in refractive index between the first ultraviolet curable resin (21) and the second ultraviolet curable resin (23) is 0.125 ~ 0.3, characterized in that the microlens-based security image film manufacturing method.