KR101146448B1 - Security film and its manufacturing method - Google Patents

Abstract

PURPOSE: A security film is provided not to use photolithography process, thereby not occurring environmental problem due to waste, and reducing the cost of apparatus. CONSTITUTION: A security film comprises a clear part and an unclear part, regularly repeating up and down, and to left and right. The clear part has diamond shape having interior angle consisting of 30-65 degree of an acute angle, and 10-35 degree of an obtuse angle. The unclear part surrounds the four edges of the clear part, and of which cross section is equal-angled echelon shape. Both sides of the cross section of the unclear part form an angle of 10-35 degree. The depth of the clear part and the unclear part is 0.03-0.1 mm. The bottom width of the unclear part is 0.005-0.05mm. The bottom width of a pair of one clear part and one unclear part is 0.05-0.15mm.

Description

Security film and its manufacturing method {SECURITY FILM AND ITS MANUFACTURING METHOD}

The present invention relates to a security film and a method of manufacturing the same, and in detail, the security film and excellent performance without having a high aspect ratio by adjusting the cabinet of the transparent portion instead of making the line width of the opaque part fine or high aspect ratio. It relates to a method of manufacturing a security film that can be produced in a relatively inexpensive and simple method using a security film mold.

In general, the display device is generally made to view the information displayed on the screen from various angles. In some cases, however, you might need a feature that makes it invisible to people other than the user. For example, if you are working with a laptop in a public place or when you are texting with a mobile phone, and you are overwhelmed by people around you, you need a function that makes the contents displayed on the screen invisible to non-workers. .

In some cases, personal privacy or corporate confidentiality may be exposed to other people through the screen of a computer or mobile phone.

In order to solve this problem, a security film is used. A security film is a film that is made to have a large aspect ratio pattern on the film so that it looks opaque when it is out of a certain viewing angle.

1 is a schematic diagram of a manufacturing method of a conventional security film. Conventional security film was used to cut the transparent film and the opaque film by sequentially bonding (Fig. 1 (a)). However, this method has a drawback in that it takes a long time to produce and a large number of processes, and decisively that the resolution formed on the security film is not good.

Thus, a method using a photolithography process (Fig. 1 (b)) has been proposed. That is, a predetermined pattern is formed by using a positive or negative photoresist mainly used in the semiconductor manufacturing process. However, using the photolithography process, it is possible to produce a pattern with a large aspect ratio, but the apparatus cost is quite expensive and unnecessary parts need to be removed with a solvent or an aqueous alkali solution, so there is a problem of costly raw materials as well as environmental problems such as waste liquid treatment.

In addition, the deeper the depth of the opaque layer to be formed, the less the light reaches and the more the angle of the opaque layer is inclined toward the bottom of the opaque layer, so that the precision processing is not performed. There was a problem that the formation is impossible.

The present invention has been invented to solve the above-described problems, the present invention is a security film excellent in performance without having a high aspect ratio by adjusting the internal angle of the transparent portion instead of making the line width of the opaque portion fine or high aspect ratio; It is an object of the present invention to provide a method for manufacturing a security film that can be produced by a relatively inexpensive and simple method using a mold for the security film.

Security film according to the present invention is a security film of the transparent portion and the opaque repeating form regularly, the transparent portion is a plurality of rhombus form connected in series, one of the cabinet of the rhombus has an acute angle of 30-65 degrees, The cross section of the opaque portion is characterized by a trapezoidal shape.

According to another preferred feature of the present invention, both sides of the cross section of the opaque portion forms an angle of 10-35 degrees, the depth of the transparent portion and the opaque portion is 0.03-0.1mm, the lower width of the opaque portion is 0.005-0.05mm, one The bottom width of the transparent and opaque parts of is 0.05-0.15mm.

Method for producing a security film according to the invention the surface processing step of planarizing one surface of the substrate; Plating step of forming a plating layer of 0.1-1.0mm thickness of copper or nickel on one surface of the flattened substrate; A master mold manufacturing step of making a master mold having grooves formed to form a plurality of rhombus-shaped transparent parts connected to each other by micro-processing the plating layer with an ultra-precision machine tool; After the nickel electroplating on the master mold to form a duplicate mold by separating it to create a duplicate mold; Resin coating step of coating a UV curable resin or a thermosetting resin on the replica mold; A transparent portion forming step of curing the UV curable resin or the thermosetting resin and separating from the replica mold; It characterized in that it comprises an opaque portion forming step of curing after inserting a mixture of a pigment and UV-curable resin or thermosetting resin that can not transmit light into the groove formed in the cured UV curable resin or thermosetting resin.

Another method for producing a security film according to the present invention is a surface processing step of processing the outer peripheral surface of the round cylindrical roll in a circular shape; Plating step of forming a plating layer of 0.1-1.0mm thickness of copper or nickel on the outer peripheral surface of the cylindrical roll; A mold manufacturing step of forming a roll mold having grooves formed to form a plurality of rhombus-shaped transparent parts connected to each other by micro-processing the plating layer with an ultra-precision machine tool; A replica film manufacturing step of manufacturing a replica film by contacting a cured film coated with a thermosetting resin or a UV curable resin on an outer circumferential surface of the roll mold; Resin coating step of coating a UV curable resin or a thermosetting resin on the replica film; A transparent portion forming step of curing the UV curable resin or the thermosetting resin and then separating the replica from the replica film; It characterized in that it comprises an opaque portion forming step of curing after inserting a mixture of a pigment and UV-curable resin or thermosetting resin that can not transmit light into the groove formed in the cured UV curable resin or thermosetting resin.

According to another preferred feature of the invention, the ultra-precision machine tool uses a diamond bite.

According to another preferred feature of the present invention, after the opaque portion forming step further comprises the step of applying an adhesive or pressure-sensitive adhesive on top of the transparent portion and the opaque portion.

The security film according to the present invention may exhibit an excellent effect as a security film because the viewing angle is narrow without making the line width of the transparent portion fine or realizing a high aspect ratio.

In addition, since the production of the security film according to the present invention does not use a photolithography process, an excellent security film using a mold can be produced simply and relatively inexpensively without expensive equipment or causing environmental problems due to waste.

1 is a schematic diagram of a manufacturing method of a conventional security film,
2 is a schematic view of a security film according to the present invention;
3 is a cross-sectional view taken along line XX 'in FIG. 2;
Figure 4 is a schematic diagram showing a manufacturing method of a security film using a flat mold according to the present invention,
5 is a perspective view of a master mold as an embodiment of the present invention,
6 is a schematic view showing a manufacturing method of a security film using a roll mold according to the present invention;
7 is a perspective view of a replica film production step.

Figure 2 is a schematic diagram of a security film according to the present invention and Figure 3 is a cross-sectional view XX 'in FIG.

As shown in Figure 2, the security film according to the present invention is a form in which the transparent portion 100 and the opaque portion 200 is regularly repeated, while the transparent portion 100 has a rhombus shape, the transparent portion of the rhombus shape An internal angle of 100 is composed of an acute angle θ 'and an obtuse angle θ ″ rather than a right angle.

In general, in order to produce an excellent security film having a narrow viewing angle, it is necessary to form an opaque portion having a fine line width and a high aspect ratio, but it is not easy to manufacture an opaque portion having a large aspect ratio fine pattern. Conventionally, a photolithography process used in a semiconductor process is used to form an opaque portion of such a fine pattern. As described above, the photolithography process has many problems such as high equipment cost and environmental problems.

Therefore, the security film in the present invention improves the performance as a security film without having a high aspect ratio by adjusting the internal angle of the transparent part 100 instead of making the line width of the opaque part 200 fine or realizing a high aspect ratio. I was.

To this end, the security film in the present invention has a form in which the transparent portion 100 of the rhombus shape having an acute angle and an obtuse angle is regularly repeated. Therefore, in the obtuse portion (b) of the security film according to the present invention, since the viewing angle is generally larger than that of the conventional security film in which the transparent portion is formed at a right angle, the function as a security film may be partially reduced, but in the acute angle portion (a) In general, the viewing angle is relatively narrower than the conventional security film formed with a transparent portion at a right angle, thereby exhibiting an excellent effect as a security film. In other words, the security film according to the present invention is arranged in a regular and excellent effect and inferior parts compared to the conventional security film, the combined length of one transparent portion 100 and opaque portion 200 in the present invention Considering that the size of 0.05-0.15mm is generally small compared to the size of one letter displayed on the security film, the security film according to the present invention displays the contents displayed on the screen at a position outside the viewing angle of the acute portion (a). It becomes difficult to know clearly, as a result, the viewing angle of the acute portion (a) can be the viewing angle of the entire security film, there is an advantage that can narrow the viewing angle without implementing a fine line width.

In particular, the internal angle of the transparent portion 100 in the present invention is preferably formed at an acute angle (θ ') of 30-65 degrees and an obtuse angle (θ ") of 115-150 degrees. As the thickness of the flesh is thin, it is difficult to make walls and breaks down when making molds.It is difficult to manufacture, and there are the same difficulties in the process of making electric poles and UV molding films.If the cabinet is over 65 degrees, the production cost increases due to excessive mold making time and acute angle. There is a problem that the shielding effect is reduced by.

On the other hand, as shown in Figure 3, in the security film according to the present invention the cross section of the transparent portion 100 and the opaque portion 200 has a trapezoidal shape. The transparent part 100 and the opaque part 200 are formed in a trapezoidal shape having opposite shapes to each other. In the present invention, the reason why the transparent portion 100 and the opaque portion 200 are formed in a trapezoidal shape is to facilitate the production of the diamond bite during mold making and to increase the mass productivity of the UV molded film.

Here, the angle A formed by the cross section of the opaque portion 200 preferably forms an angle of 10-35 degrees. If the angle is less than 10 degrees, there is a problem that the defective rate is increased in the mold production, if the angle exceeds 35 degrees, the area of the transparent portion is reduced, there is a problem that the transmittance of the security film product is significantly lowered.

In addition, in the present invention, the depth D of the transparent part 100 and the opaque part 200 is 0.03-0.1 mm, the lower width B of the opaque part 200 is 0.005-0.05 mm, and one transparent part ( 100) and the lower width (C) combined with the opaque portion 200 is preferably 0.05-0.15mm.

If the depth is less than 0.03mm, the width of the transparent part is reduced, making it difficult to manufacture the mold, or if the width of the transparent part is not reduced, the shielding effect is remarkably lowered, thus preventing the role of a security film. It becomes difficult and the thickness of the security film is thick, there is a problem that the marketability of the product is reduced. In addition, if the lower width of the opaque portion 200 is less than 0.005mm, there is a problem in the production of the mold, the reality is difficult, and if it exceeds 0.05mm, there is a problem that the width of the transparent portion is reduced. In addition, the lower width is less than 0.05mm, there is a problem in the production of the mold, there is a problem that is difficult, and if more than 0.15mm there is a problem that the width of the transparent portion is reduced.

Next, look at the manufacturing method of the security film according to the present invention.

In the present invention, to produce a security film of excellent performance and to overcome the disadvantages of the conventional method for manufacturing a security film using a photolithography process, to produce a flat or roll-shaped mold, using the mold to produce a security film.

First, the manufacturing method of the security film using a flat mold will be described.

The manufacturing method of the security film using the planar mold according to the present invention includes a surface processing step, plating step, master mold manufacturing step, replica mold manufacturing step, transparent portion forming step, opaque portion forming step. Each step will be described below.

Figure 4 is a schematic diagram showing a manufacturing method of a planar mold according to the present invention. The surface processing step is to planarize one surface of the substrate 11. In the present invention, various kinds of substrates may be used as the substrate 11, but it is preferable to use stainless steel (SUS). Meanwhile, one surface of the substrate is planarized to form a pattern in a subsequent process. The planarization method is not particularly limited, but may be a physicochemical polishing method or the like. The degree of flattening is later flattened so that the flatness in the master mold can be 0.1-1.0 μm. If the flatness is less than 0.1μm, there is a problem in the accuracy of processing accuracy, and if it exceeds 1.0μm, there are various problems such as decrease in transmittance and eye irritation that can be caused by failing to reliably remove the resin of the opaque portion of the security film product. . After the surface processing step, the flattened substrate 11 is prepared as shown in FIG.

In the plating step, the plating layer 12 is formed by plating copper or nickel on one surface of the flattened substrate 11 in the surface processing step. Here, the plating of copper or nickel may be carried out using a commonly known method. The reason for plating copper or nickel is that copper or nickel is easier to form a pattern in a high precision machine tool than sus, and the plating layer 12 is formed to a thickness of 0.1-1.0 mm. Since the maximum thickness of the opaque layer and the transparent layer in the present invention is 0.1mm, the plating layer 12 should be deposited thicker than this, and if the thickness of the plating layer 12 exceeds 1.0mm, the cost increases as well as the risk of defects and the mold durability. There is a problem.

In the master mold manufacturing step, the plating layer 12 formed in the plating step is finely processed by a high precision machine tool to produce a master mold 10 having a rhombus groove. The ultra-precision machine tool is a device capable of forming a fine pattern as in the present invention, and the ultra-precision machine tool used in the present invention preferably uses the diamond bite to make a rhombus groove 13. 4 (c) shows the master mold 10 completed through the master mold manufacturing step, and the groove 13 is formed in the plating layer 12. Here, the groove 13 processed by the ultra-precision machine tool is processed so that the transparent portion 100 having a rhombus shape is formed as shown in FIGS. 2 to 3. 5 is a perspective view of the master mold 10 as an embodiment of the present invention.

In the replica mold manufacturing step, a nickel electroplating layer is formed on the master mold 10 by nickel electroplating, and then a duplicate mold 20 is formed by separating them. The replica mold 20 produced in this process is a master mold. It will have a shape opposite to (10). As shown in (d) of FIG. 4, a replica mold 20 is formed on the master mold 10 by nickel electroplating, and the replica mold 20 is formed from the master mold 10 as shown in FIG. After separation, the upper surface of the groove 21 of the replica die 20 is formed upward.

Resin coating step is a step of coating the resin to form a transparent layer on the upper surface of the replication mold (20).

In the resin coating step, after attaching the film 31 to the upper surface of the replication mold 20, the transparent resin 32 is injected into the groove 21 formed in the replication mold 20 to form the upper surface of the replication mold 20. Is coated with a transparent layer.

Here, the film 31 is a transparent film, which adopts a material having a material, a standard, and a component required for producing a security film, and selects an appropriate resistance value for temperature, deformation, pressure, humidity, and discoloration required for producing the security film. Polypropylene oxide, polyisocyanate, hydroxyethyl, polyvinyl chloride (PVC), polyethylene terephthalate (PET), monoacrylate, polyacrylate, polymethyl methacrylate, polyurethane, polycarbonate (PC), polyethylene , Methacrylate, polypropylene, cellulose acetate butyrate (CAB), ethylene vinyl acetate (EVA), polyvinyl alcohol (PVA), acrylate, hydroxyethyl, propylene oxide, acrylic and copolymers thereof It is preferred to consist of one or more components selected.

In particular, the polyurethane-reinforced fabrics, including polyurethane, can protect key structures, such as computer monitors, cell phones, LCD screens, and building glass, that are sensitive to shocks and damage from external impacts and scratches. have.

In addition, the transparent resin 32 used in the present invention may be a thermosetting resin or a UV curing resin, specific examples thereof include polypropylene oxide, polyethylene, polypropylene, ethylene vinyl acetate (EVA), polyvinyl alcohol (PVA), Polyvinyl chloride (PVC), polyethylene terephthalate (PET), cellulose acetate butylate (CAB), monoacrylate polyacrylate, polymethyl methacrylate, polyurethane, polycarbonate, propylene oxide, polyisocyanate, hydroxyethyl Acrylate, hydroxyethyl methacrylate, or copolymers thereof.

In the above description, the resin 32 is injected into the groove 21 of the replica mold 20 after the film 31 is attached. However, the film 31 is injected after the resin 32 is injected into the groove 21. It may be proceeded by attaching.

In the transparent portion forming step, the UV cured resin or the thermosetting resin is cured using UV or heat according to its properties, and then the cured resin 32 is separated from the replica mold 20 to form a transparent part. As the film 31 and the resin 32 adhere to each other during the curing process, the transparent part 32 having a shape opposite to the replica mold 20 is formed.

In the opaque portion forming step, a mixture of a pigment and a resin that cannot transmit light is inserted into the grooves 33 between the transparent portions 32 formed in the transparent portion forming step and then cured to form the opaque portion 40. . Here, the mixture inserted into the grooves 33 between the transparent portions 32 is a mixture of pigments and resins, and resins are resins usable in adhesive inks, ethylene vinyl acetate (EVA), polyvinyl alcohol (PVA), polychloride Vinyl (PVC), polyethylene terephthalate (PET), polyacrylate, polymethylmethacrylate, polyurethane, polycarbonate, polyethylene, polypropylene, cellulose acetate butyrate (CAB), polyisocyanate, polypropylene oxide, hydroxy Ethyl acrylate, hydroxyethyl methacrylate, propylene oxide monoacrylate, or copolymers thereof.

Pigments use pigments that cannot transmit light. As long as the pigment can not transmit light, it is irrelevant whether it is black or white. Representative examples of the pigment include carbon black. That is, the mixture described above is a mixture of one or more resins and pigments described above, which are subjected to a curing process after being inserted into the grooves between the transparent portions 32. Here, the method of inserting the mixture into the grooves between the transparent portions 32 may be a method of removing the mixture in a portion other than the groove after applying the mixture on the upper portion of the transparent portion, or inserting only the groove by a method such as gravure printing. There is also a way.

The security film completed through the above process will have the shape of Figure 4 (h). An adhesive or an adhesive may be applied to the upper part of the completed security film, or may be released by attaching a protective film to the upper part.

The protective film may use the same kind as the film used in the above-mentioned transparent layer forming step.

The adhesive may be formed using a known adhesive, such as an acrylic, epoxy, polyurethane or polyamide adhesive, which can adhere the security film and the product well together. There is no particular limitation on the type of the pressure-sensitive adhesive, but examples thereof include acrylic pressure-sensitive adhesives or epoxy pressure-sensitive adhesives.

Next, look at the manufacturing method using a roll mold.

The production method using the roll mold includes a surface processing step, a plating step, a master mold making step, a replica film manufacturing step, a resin coating step, a transparent part forming step, and an opaque part forming step. Since the resin coating step and the subsequent steps are the same as the manufacturing method using the flat mold described above, further description is omitted here. In addition, the description overlapping with the manufacturing method using the planar mold described above will be omitted.

Figure 6 is a schematic diagram showing a manufacturing method of a security film using a roll mold according to the present invention. In the surface processing step, the surface of the substrate is polished in a cylindrical shape, and the other contents are the same as in the case of the production of the security film using the flat mold described above.

Since the plating step and the master mold manufacturing step are the same as those of the above-described flat mold except for using a roll-shaped mold, a description thereof will be omitted.

The duplicate film production step corresponds to the duplicate mold production step in the above-described flat mold, where a duplicate film is produced instead of the duplicate mold. FIG. 7 is a perspective view of a replica film manufacturing step, in which a film 25 coated with a resin 26 for forming a replica film is placed below a roll-shaped master mold 10. Here, the film 25 coated with the resin 26 passes through the lower portion of the roll-shaped master mold 10, and the shape engraved on the master mold 10 is engraved on the film coated with resin as it is. Thereafter, the film 25 to which the resin 26 is applied is cured to complete the replica film.

To this end, the film 25 may be a film used in the transparent layer forming step in the method of manufacturing a security film using the planar mold, and the resin 26 may be UV curable or thermosetting resin. The transparent resin can be used.

Subsequent steps are the same as in the case of using a flat mold, so detailed description thereof will be omitted.

1O: master mold
11: Substrate
12: Plating layer
13: Home
20: replication mold
25: Film
26: resin
31: Film
32: resin (transparent)
40: Opaque part
100: transparent
200: Opaque part

Claims (7)

The transparent and opaque parts of the security film of the form repeated regularly, up, down, left and right,
The transparent portion is a rhombus shape having an internal angle consisting of an acute angle of 30-65 degrees and an obtuse angle of 115-150 degrees,
The opaque portion is a security film, characterized in that the cross-section wraps the corners of the four sides of the transparent portion of the rhombus-shaped cross-section. According to claim 1, wherein both sides of the cross section of the opaque portion forms an angle of 10-35 degrees, the depth of the transparent portion and the opaque portion is 0.03-0.1mm, the lower width of the opaque portion is 0.005-0.05mm, one transparent portion The lower width combined with the opaque portion is a security film, characterized in that 0.05-0.15mm. A surface processing step of planarizing one surface of the substrate;
Plating step of forming a plating layer of 0.1-1.0mm thickness of copper or nickel on one surface of the flattened substrate;
A master mold manufacturing step of making a master mold having grooves formed to form a plurality of rhombus-shaped transparent parts connected to each other by micro-processing the plating layer with an ultra-precision machine tool;
After the nickel electroplating on the master mold to form a duplicate mold by separating it to create a duplicate mold;
Resin coating step of coating a UV curable resin or a thermosetting resin on the replica mold;
A transparent portion forming step of curing the UV curable resin or the thermosetting resin and separating from the replica mold;
And a non-transparent buoy forming step of curing after inserting a mixture of a pigment and UV-curable resin or thermosetting resin that cannot transmit light into the groove formed in the cured UV-curable resin or thermosetting resin. How to make. Surface processing step of processing the outer peripheral surface of the round cylindrical roll in a circle;
Plating step of forming a plating layer of 0.1-1.0mm thickness of copper or nickel on the outer peripheral surface of the cylindrical roll;
A mold manufacturing step of forming a roll mold having grooves formed to form a plurality of rhombus-shaped transparent parts connected to each other by micro-processing the plating layer with an ultra-precision machine tool;
A replica film manufacturing step of manufacturing a replica film by contacting a cured film coated with a thermosetting resin or a UV curable resin on an outer circumferential surface of the roll mold;
Resin coating step of coating a UV curable resin or a thermosetting resin on the replica film;
A transparent portion forming step of curing the UV curable resin or the thermosetting resin and then separating the replica from the replica film;
And a non-transparent buoy forming step of curing after inserting a mixture of a pigment and UV-curable resin or thermosetting resin that cannot transmit light into the groove formed in the cured UV-curable resin or thermosetting resin. How to make. According to claim 3 or 4, wherein the rhombus-shaped transparent portion has one of the inner angle of the rhombus has an acute angle of 30-65 degrees, the cross section of the opaque portion is a trapezoidal shape, both sides of the opaque section cross-section of 10-35 degrees Forming an angle, the lower portion of the opaque portion is 0.005-0.05mm, the depth of the opaque portion manufacturing method of the security film, characterized in that 0.03-0.1mm. The method of claim 3 or 4, wherein the bite of the ultra-precision machine tool is made of diamond material. The method of claim 3 or 4, further comprising applying an adhesive or an adhesive on the transparent portion and the opaque portion after the opaque portion forming step.

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