Electromagnetic wave shielding film

Abstract

According to an embodiment of the present invention, the electromagnetic wave shielding film is characterized in that the electromagnetic wave shielding film comprises: a substrate; and an electrode pattern disposed on a surface of the substrate, and comprising metal particles, wherein the metal particles respectively comprise first particles having a size of a first range and second particles having a size of a second range smaller than the first range, the number of second particles being greater than the number of first particles, and at least one first particle being mixed among the second particles.

Description

Technical Field

[0001] This invention relates to an electromagnetic wave shielding film, specifically to an electromagnetic wave shielding film with improved electromagnetic wave shielding efficiency and high electromagnetic wave shielding performance in all frequency bands of electromagnetic waves. Background Technology

[0002] Various electronic devices generate harmful electromagnetic waves during operation. These harmful electromagnetic waves not only have adverse effects on the human body, but also cause abnormal operation or radio interference between the corresponding electronic devices and other devices, thereby reducing product performance and shortening product life.

[0003] In particular, most monitors are prone to generating these harmful electromagnetic waves due to their operating characteristics. Therefore, electromagnetic wave shielding components need to be used on the front surface of the monitor to block these harmful electromagnetic waves. These electromagnetic wave shielding components not only need to block electromagnetic waves, but also should avoid reducing the transparency of the monitor screen.

[0004] On the other hand, conventional electromagnetic wave shielding components for the front surface of a display include a metal mesh. In this case, a copper mesh is typically used as the metal mesh, which is formed by etching copper foil and has a thin film shape.

[0005] To manufacture such a copper mesh film, the following steps are required: forming a copper thin film by electroplating, blackening treatment to improve image quality, surface roughness treatment, and anti-oxidation treatment. Then, after the copper foil is adhered to the PET film, the copper foil is subjected to photoresist coating, exposure, development, and etching processes using photolithography.

[0006] However, this manufacturing method is complex and requires photolithography, which not only increases manufacturing costs but also wastes materials because more than 90% of the copper needs to be removed by etching.

[0007] To address these issues, a method has been proposed for manufacturing electromagnetic wave shielding components using the following conductive paste.

[0008] Figure 1 A conventional electromagnetic wave shielding component 10 using conductive paste is shown.

[0009] according to Figure 1The conventional electromagnetic wave shielding component 10 includes a glass substrate 11, an electromagnetic wave shielding pattern 12 formed on one surface of the glass substrate 11, and a grounding electrode 13. In this case, the electromagnetic wave shielding pattern 12 is formed by etching conductive paste onto the glass substrate 11. That is, by using conductive paste to form the electromagnetic wave shielding pattern 12, the conventional electromagnetic wave shielding component 10 can achieve electromagnetic wave shielding performance more cheaply and simply.

[0010] However, the shielding performance of conventional electromagnetic wave shielding components 10 using conductive paste is not high. In particular, there is a problem that they only provide shielding performance for a portion of the electromagnetic wave frequency band.

[0011] In particular, as electronic devices become increasingly complex and high-performance, they require not only higher electromagnetic shielding performance but also high electromagnetic shielding performance across various electromagnetic frequency bands. Therefore, a more advanced technology than existing technologies is needed to meet these demands.

[0012] However, the matters described above as background art are only for enhancing the understanding of the background of the present invention, and should not be construed as an admission that the present invention belongs to the prior art known to those skilled in the art. Summary of the Invention

[0013] Technical problems to be solved

[0014] In order to solve the problems of the prior art, the present invention aims to provide an electromagnetic wave shielding film, wherein the electromagnetic wave shielding efficiency of the electromagnetic wave shielding film increases with the increase of the conductivity of the conductive paste, and has high shielding performance in all frequency bands of electromagnetic waves.

[0015] However, the problems to be solved by the present invention are not limited to those described above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

[0016] Technical solutions to solve technical problems

[0017] An electromagnetic wave shielding film according to an embodiment of the present invention for solving the above-mentioned problems includes: a substrate; and an electrode pattern disposed on a surface of the substrate and comprising metal particles, wherein the metal particles respectively include first particles having a size of a first range and second particles having a size of a second range smaller than the first range, the number of second particles being greater than the number of first particles, and at least one first particle being mixed among the second particles.

[0018] An electromagnetic wave shielding film according to another embodiment of the present invention includes: a substrate; an electrode pattern disposed in a direction on one surface of the substrate and comprising metal particles; and a transparent conductive layer disposed in a direction on one surface of the electrode pattern or in a direction on another surface of the substrate, and covering the electrode pattern arranged along one surface of the substrate, wherein the metal particles respectively comprise first particles having a size of a first range and second particles having a size of a second range smaller than the first range, the number of second particles being greater than the number of first particles, and at least one first particle being mixed among the second particles.

[0019] The electrode pattern may include a first structure in which a plurality of second particles surround the first particle.

[0020] The electrode pattern may also include a second structure, which is composed of a plurality of second particles connected together.

[0021] The electrode pattern may include a greater number of second structures than the first structure.

[0022] The size of the first range can be more than twice the size of the second range.

[0023] The size of the first range can be greater than or equal to 1 μm and less than or equal to 1.5 μm; the size of the second range can be greater than or equal to 400 nm and less than or equal to 450 nm.

[0024] The ratio of the number of the first particle to the number of the second particle can be from 2:8 to 4:6.

[0025] The electrode pattern can be formed as a grid pattern shape, which includes a plurality of polygons arranged along one surface of the substrate.

[0026] The plurality of polygons may include a plurality of irregular polygons that are adjacent to each other, and the spacing values ​​of the adjacent irregular polygons may be different from each other.

[0027] The irregular polygon may have four or more vertices, and the extension directions of each side may be different from each other.

[0028] In the irregular polygon, the angles formed by the edges that are adjacent to each other with each vertex as the center can be different.

[0029] The electrode pattern may be formed along a groove, which is formed on one surface of the substrate or on one surface of a resin layer disposed on one surface of the substrate.

[0030] The electrode pattern can be formed as a relief shape on one surface of the substrate.

[0031] The metal particles can be selected from silver (Ag), copper (Cu), aluminum (Al), nickel (Ni) and chromium (Cr), and the conductive layer can be selected from ITO, silver (Ag) nanotubes, graphene, carbon nanotubes, silver (Ag) particles or conductive polymers.

[0032] According to one or another embodiment of the present invention, the substrate of the electromagnetic wave shielding film is a transparent substrate, and therefore can be used as a light-transmitting screen device for a display.

[0033] The effects of the invention

[0034] The present invention, with the configuration described above, not only provides improved electromagnetic wave shielding performance against electromagnetic waves of any frequency band generated from products to which the present invention is applied, but also has the advantage of shielding electromagnetic waves of various frequency bands generated from complex products or various fields with a comprehensive high shielding rate without being limited by frequency band.

[0035] Furthermore, when the electrode pattern of the present invention includes irregular polygons, mutual interference with the pixel pattern of the display can be prevented, thereby avoiding moiré effects and improving visibility at all angles of the plane. In addition, such irregular polygons can suppress pattern aggregation of the electrode pattern, resulting in a more balanced distribution of the electrode pattern, thus having the advantage of further improving the electromagnetic wave shielding effect.

[0036] The effects of the present invention are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. Attached Figure Description

[0037] Figure 1 A conventional electromagnetic wave shielding component 10 using conductive paste is shown.

[0038] Figure 2 A perspective view of an electromagnetic wave shielding film 100 according to a first embodiment of the present invention is shown.

[0039] Figure 3 A partial cross-sectional view of one side of an electromagnetic wave shielding film 100 according to a first embodiment of the present invention is shown.

[0040] Figure 4 A partial top view of an electrode pattern 130 of an electromagnetic wave shielding film 100 according to a first embodiment of the present invention, showing a grid pattern of regular polygons 132.

[0041] Figure 5A partial top view and an enlarged view of an electrode pattern 130 having a grid pattern of irregular polygons 133 are shown in the electromagnetic wave shielding film 100 according to a first embodiment of the present invention.

[0042] Figure 6 An example of a first structure 136A and a second structure 136B included in the pattern line 131 of the electrode pattern 130 is shown.

[0043] Figure 7 Various comparative aspects of the electromagnetic wave shielding film 100 according to the first embodiment of the present invention, which has been actually manufactured, and its comparative examples are shown.

[0044] Figure 8 The electromagnetic shielding efficiency curves of the electromagnetic wave shielding film 100 according to the first embodiment of the present invention and its comparative examples at different frequencies are shown.

[0045] Figure 9 A partial cross-sectional view of one side of an electromagnetic wave shielding film 200 according to a second embodiment of the present invention is shown.

[0046] Figure 10 The electromagnetic shielding efficiency curves of an electromagnetic wave shielding film 200 according to a second embodiment of the present invention, and its comparative examples, at different frequencies are shown.

[0047] Figure 11 An example is shown of an electromagnetic wave shielding film 100 according to a first embodiment of the present invention being used as a screen device in a display.

[0048] Figure 12 These are photographs comparing and illustrating electrode patterns according to embodiments and comparative examples of the present invention.

[0049] Figure 13 The diagrams are for comparing and illustrating the characteristics of screen devices according to embodiments and comparative examples of the present invention.

[0050] Figure 14 These are images used to illustrate whether moiré patterns occur in a screen device according to an embodiment of the present invention. Figure 15 This is an image showing a display using a screen device according to an embodiment of the present invention. Detailed Implementation

[0051] The above-described objects, methods, and effects of the present invention will become clearer from the accompanying drawings and the following detailed description, and accordingly, those skilled in the art can readily implement the technical concept of the present invention. Furthermore, in describing the present invention, detailed descriptions of related known structures or functions are omitted if they are considered to deviate from the spirit of the invention.

[0052] The terminology used in this specification is for describing embodiments and is not intended to limit the invention. In this specification, unless otherwise stated, the singular form also includes the plural form in certain circumstances. In this specification, terms such as “comprising,” “including,” “setting,” or “having” do not exclude the presence or addition of one or more other components besides those mentioned.

[0053] In this specification, terms such as “or” or “at least one” may refer to one of the words listed together, or to a combination of two or more. For example, “A or B” and “at least one of A and B” may include only one of A or B, or may include both A and B.

[0054] In this specification, the features, variables, or values ​​described after terms such as "for example" may not perfectly match the information provided, and therefore should not be limited to specific embodiments of the invention in accordance with effects equivalent to variations of permissible errors, measurement errors, limits of measurement accuracy, and other well-known factors.

[0055] In this specification, it should be understood that when a component is referred to as being "connected" or "connected" to other components, it may mean that the component is directly connected or connected to other components, or that there may be other components in between. Conversely, when a component is referred to as being "directly connected" or "directly connected" to other components, it should be understood that there are no other components in between.

[0056] In this specification, it should be understood that when referring to a component "on" or "in contact" with another component, it may mean that the component is in direct contact or connection with the other component, but there may also be other components in between. Conversely, when referring to a component "directly on" or "directly in contact" with another component, it can be understood that there are no other components in between. Other expressions used to describe the relationship between components, such as "between" and "directly between," can be interpreted in the same way.

[0057] In this specification, terms such as "first" and "second" may be used to describe various components, but these components should not be limited by such terms. Furthermore, the terms should not be construed as limiting the order of each component and may be used to distinguish one component from another. For example, "first component" may be referred to as "second component," and similarly, "second component" may be referred to as "first component."

[0058] Unless otherwise defined, all terms used in this specification may be used in the sense commonly understood by one of ordinary skill in the art to which this invention pertains. Furthermore, unless specifically and explicitly defined, terms as defined in common dictionaries will not be interpreted ideally or excessively.

[0059] In the following, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0060] Figure 2 A perspective view of an electromagnetic wave shielding film 100 according to a first embodiment of the present invention is shown. Figure 3 A partial cross-sectional view of one side of an electromagnetic wave shielding film 100 according to a first embodiment of the present invention is shown. That is, Figure 3 It shows along Figure 2 A portion of the cross section after the line A-A' is cut off.

[0061] The electromagnetic wave shielding film 100 according to the first embodiment of the present invention has electromagnetic wave shielding performance, and as... Figure 2 and Figure 3 As shown, it includes a substrate 110 and an electrode pattern 130. This electromagnetic wave shielding film 100 according to a first embodiment of the present invention can be used on the front surface of a display as a light-transmitting screen device (hereinafter referred to as "screen device").

[0062] The substrate 110, as a flat substrate, can be made of a non-conductive material. In a screen device, the substrate 110 can be made of a light-transmitting transparent material. Furthermore, the substrate 110 can be a glass substrate or a thin-film substrate made of various resin materials. For example, the resin material substrate 110 can include various resin materials such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polycarbonate (PC), or polymethyl methacrylate (PMMA). The light transmittance of this substrate 110 can be 80% or higher. In this case, the closer the light transmittance is to 100%, the better the light transmittance; the closer the light transmittance is to 0%, the worse the light transmittance.

[0063] The thickness of the substrate 110 can be approximately greater than or equal to 10 μm and less than or equal to 250 μm. When the thickness of the substrate 110 is less than 10 μm, it may be difficult to form an electrode pattern 130 of the desired thickness on the substrate 110. Furthermore, when the thickness of the substrate 110 exceeds 250 μm, the brightness of the screen device may be lower than the desired brightness.

[0064] The electrode pattern 130 is made of a conductive material containing metal particles. This electrode pattern 130 is formed as various patterns arranged side-by-side in a plane along one surface of the substrate 110, and can perform a shielding function against electromagnetic waves passing through its surroundings. The electrode pattern 130 can be in the form of metal particles cured with an adhesive resin. For example, the metal particles can include various conductive metal particles such as silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), and chromium (Cr), and can have various sizes.

[0065] In the top view, the electrode pattern 130 can be formed as an irregular mesh pattern. However, the electrode pattern 130 is not limited to this, and in the top view, it can be formed as various patterns, such as regular mesh patterns, regular or irregular line patterns, and polygonal patterns.

[0066] The electrode pattern 130 can be formed on one surface of the substrate 110. That is, the electrode pattern 130 can be formed on one surface of the substrate 110, or on one surface of the resin layer 120 disposed on one surface of the substrate 110. This resin layer 120 can be made of a transparent plastic material to transmit light. For example, the resin layer 120 can be made of a material different from the material of the substrate 110, and can include various resin materials such as polyurethane acrylate.

[0067] To form an electrode pattern 130 on one surface of the substrate 110, an imprinting process is performed using a mold with a shape corresponding to the electrode pattern 130. This forms a recessed groove with a shape corresponding to the electrode pattern 130 on one surface of the substrate 110 or the resin layer 120. Subsequently, by filling the formed groove with a conductive material, an electrode pattern 130 with the groove shape can be formed. When the substrate 110 is a resin substrate, the electrode pattern 130 can be formed on one surface of the substrate 110. Furthermore, when the substrate 110 is a resin substrate or a glass substrate, after coating one surface of the substrate 110 with the resin layer 120, the electrode pattern 130 can be formed on one surface of the resin layer 120.

[0068] Specifically, after using a blade to fill a conductive paste consisting of conductive metal particles and a binder into an etched groove formed on one surface of the substrate 110 or resin layer 120, heat or ultraviolet light is applied to cure the conductive paste. Then, a cleaning component is used to clean and remove any residual conductive paste that was not filled into the etched groove on the surface of the substrate 110 or resin layer 120. Finally, the metal particles are sintered through an additional heat treatment process to form the electrode pattern 130.

[0069] Although the intaglio electrode method, which forms the electrode pattern 130 by filling conductive material into an intaglio groove on one surface of the substrate 110 or resin layer 120, has been described as an example, the annotated electrode method, which protrudes a predetermined thickness on one surface of the substrate 110 or resin layer 120, can also be applied. In this case, the electrode pattern 130 can be formed by annotating a conductive paste on one surface of the substrate 110 or resin layer 120 using gravure printing or the like. Of course, the conductive paste can also be cured by applying heat or ultraviolet light, and the metal particles can be sintered by subsequent heat treatment.

[0070] Figure 4 A partial top view of an electrode pattern 130 having a grid pattern of regular polygons 132 is shown in an electromagnetic wave shielding film 100 according to a first embodiment of the present invention. Figure 5 A partial top view and an enlarged view thereof are shown of an electrode pattern 130 of an electromagnetic wave shielding film 100 having a grid pattern of irregular polygons 133 according to a first embodiment of the present invention.

[0071] On the other hand, the electrode pattern 130 can function as a touch sensor. In this case, the electrode pattern 130 can also be referred to as a patterned electrode, a detection electrode, a sensor layer, or an electrode layer.

[0072] Reference Figure 4 and Figure 5 The electrode pattern 130 may include a plurality of pattern lines 131. The plurality of pattern lines 131 may intersect each other in a plurality of directions to form a plurality of regular polygons 132 or irregular polygons 133. That is, each side of the plurality of regular polygons 132 or irregular polygons 133 may be formed by the pattern lines 131. On the other hand, the pattern lines 131 may be referred to as fine wires.

[0073] When pattern lines 131 are formed using an etching electrode method that fills the interior of the etched surface with conductive material, the width W of each pattern line 131 can be approximately greater than or equal to 4 μm and approximately less than or equal to 10 μm. Furthermore, the depth H of each pattern line 131 can be approximately greater than or equal to 4 μm and approximately less than or equal to 10 μm. The cross-sectional shape of the pattern line 131 can be rectangular. When the width W and depth H of the pattern line 131 are both less than 4 μm, it may be difficult to manufacture the electrode pattern 130. When the width W and depth H of the pattern line 131 are both greater than 10 μm, the light transmittance of the electrode pattern 130 may be affected, and the screen visibility of the display device using the screen may deteriorate. On the other hand, the closer the width W and depth H of the pattern line 131 are to 4 μm, the better the light transmittance of the electrode pattern 130; the closer they are to 10 μm, the more accurately the capacitance change caused by user touch can be sensed.

[0074] When pattern lines 131 are formed by a method of forming a raised electrode protruding from one surface of substrate 110 or resin layer 120, the width of each pattern line 131 can be approximately greater than or equal to 0.5 and approximately less than or equal to 10 μm, and the thickness can be approximately 0.2 μm to approximately less than or equal to 5 μm. The cross-sectional shape of such pattern lines 131 can be rectangular.

[0075] Multiple regular polygons 132 or irregular polygons 133 are arranged along the upper surface of the substrate 110 to form an electrode pattern 130. That is, the electrode pattern 130 may include multiple regular polygons 132 or irregular polygons 133, which are formed by the intersection of regular or irregular fine wires. Here, a regular shape refers to a shape with a set pattern, and an irregular shape refers to a shape from which no pattern can be found. In other words, although the irregular shape is defined as a predetermined shape, a regular and repeating pattern cannot be derived from the predetermined shape. Therefore, the multiple irregular polygons 133 may have different shapes. However, the electrode pattern 130 may preferably include multiple irregular polygons 133 to avoid moiré patterns.

[0076] The spacing values ​​P of the multiple irregular polygons 133 are all within a preset range. Furthermore, adjacent irregular polygons 133 may each have different spacing values ​​P. In this case, the spacing value P represents the maximum value among the spacing values ​​between the vertices V of the irregular polygons 133. A detailed description of these multiple irregular polygons 133 will be given later.

[0077] On the other hand, the shielding performance of the electrode pattern 130 is affected by the size range of the metal particles representing conductivity. In this case, the size of the metal particles can be the maximum length from one side of the metal particle to the other, but is not limited to this.

[0078] In other words, existing electrode patterns have limited shielding performance because they only include metal particles with approximate size ranges. Specifically, existing electrode patterns offer low shielding performance, particularly only providing shielding against a portion of electromagnetic wave frequencies.

[0079] To address these issues, the present invention forms the electrode pattern 130 by mixing metal particles of different sizes with conductive paste. This increases the packing density of the metal particles in the electrode pattern 130, thereby improving conductivity and further enhancing electromagnetic wave shielding as resistance decreases. Specifically, the larger the contact area of ​​the metal particles used as the material for the electrode pattern 130, the greater the conductivity. When small-sized metal particles are mixed with larger-sized metal particles in between, the contact area between these particles increases, thereby increasing the packing weight of metal particles in the same space, resulting in a reduction in overall resistance. Consequently, the electromagnetic wave shielding efficiency of the electromagnetic wave shielding film 100 is further improved due to the reduced resistance of the electrode pattern 130.

[0080] Figure 6 An example of a first structure 136A and a second structure 136B included in the pattern line 131 of the electrode pattern 130 is shown.

[0081] Specifically, refer to Figure 6 The pattern lines 131 of the electrode pattern 130 respectively include a plurality of first particles 134 having a first range of size and a plurality of second particles 135 having a second range of size. Here, the second range is a smaller size range than the first range. That is, the size of the first particles 134 is larger than the size of the second particles 135. Of course, the sizes of the first particles 134 can be different from each other, and the sizes of the second particles 135 can also be different from each other.

[0082] In particular, the electrode pattern 130 may include a first structure 136A, which is formed by sintering and mixing at least one second particle 135 with a first particle 134. This first structure 136A has a structure in which small-sized second particles 135 surround large-sized first particles 134, thus increasing the contact area between particles and thereby improving shielding performance.

[0083] At this point, since it is necessary to include a first structure 136A consisting of second particles 135 surrounding the first particle 134, the conductive paste preferably contains more second particles 135 than the first particle 134. That is, preferably, the electrode pattern 130 contains more second particles 135 than the first particle 134.

[0084] Furthermore, since the number of second particles 135 is greater than that of first particles 134, the electrode pattern 130 may also include a second structure 136B in which a plurality of second particles 135 are electrically connected. This second structure 136B can be electrically connected to the first structure 136A. In this case, since the first structure 136A greatly improves the shielding performance, it is preferable that the electrode pattern 130 includes more first structures 136A than second structures 136B. However, in some cases, for example, when the number of large-size first particles 134 increases, and the filling of the grooves is not smooth, or when product characteristics require particles to be filled in narrow grooves, it is necessary to reduce the number of large-size first particles 134. Therefore, the electrode pattern 130 may include more second structures 136B than first structures 136A.

[0085] The first structure 136A and the second structure 136B can be ultimately formed during the curing and sintering process of the conductive paste. In particular, a portion of the individual particles 134 and 135 inside the conductive paste are partially melted by the heat transferred during the sintering process, which makes the surrounding particles electrically connected to each other, thereby forming the first structure 136A or the second structure 136B.

[0086] Preferably, the size of the first range can be approximately twice or more than four times the size of the second range. For example, the size of the first range can be greater than or equal to 1 μm and less than or equal to 1.5 μm; the size of the second range can be greater than or equal to 400 nm and less than or equal to 450 nm. When the size of the first range is less than twice that of the second range, the number of second particles 135 surrounding the first particle 134 is too small, thus limiting the increase in the contact area between particles. Furthermore, when the size of the first range exceeds four times that of the second range, the size and weight difference between the first particle 134 and the second particle 135 is too large, so when mixing metal particles, there is a tendency for the first particle 134 to be unevenly dispersed and aggregated in the second particle 135, which may result in poor filling performance when filling the etched groove.

[0087] On the other hand, the mixing ratio between the first particle 134 and the second particle 135 may have a significant impact on the resistance value and shielding performance of the electrode pattern 130. Therefore, the ratio of the number of the first particle 134 to the number of the second particle 135 (number of first particles: number of second particles) can preferably be from 2:8 to 4:6.

[0088] That is, when the ratio of the number of first particles 134 is less than 2:8, the insufficient number of first particles 134 will result in an insufficient number of first structures 136A inside the pattern line 131, which will cause a decrease in shielding performance. Furthermore, when conductive paste is filled into the etched groove, the weight density of the metal particles 134 and 135 in the same space becomes relatively low, so the resistance may become relatively high.

[0089] On the other hand, when the ratio of the number of first particles 134 is greater than 4:6, the insufficient number of second particles 135 surrounding the first particles 134 may lead to an excessively small size of the first structure 136A, resulting in a decrease in shielding performance. Furthermore, when conductive paste is filled into the etched groove, the interference between the large-sized first particles 134 increases the possibility of voids being generated within the etched groove, which may lead to a decrease in charging capability and an increase in resistance.

[0090] With this in mind, the optimal ratio of the first particle 134 to the second particle 135 can be 3:7. That is, while increasing the contact area between the first particle 134 and the second particle 135 filling the groove, and considering the high filler weight density, when the ratio of the first particle 134 to the second particle 135 is 3:7, the electrode pattern 130 can achieve low resistance and effectively improve shielding performance.

[0091] Figure 7 Various comparative aspects of the electromagnetic wave shielding film 100 according to the first embodiment of the present invention, which has been actually manufactured, and its comparative examples are shown. Figure 8 Electromagnetic wave shielding film 100 according to the first embodiment of the present invention, and its comparative examples, are shown in electromagnetic wave shielding efficiency curves at different frequencies. That is, at... Figure 8 In the diagram, the x-axis represents frequency, and the y-axis represents electromagnetic shielding efficiency, with the unit being decibel (dB).

[0092] On the other hand, for performance testing, an electromagnetic wave shielding film 100 according to the first embodiment of the present invention was manufactured. Specifically, after coating a resin layer 120 of polyurethane acrylate resin onto a transparent PET substrate 110, the resin layer was pressed with a mold having a positive pattern to form grooves with negative patterns. Next, a conductive paste of silver (Ag) particles was filled into the negative grooves, and the paste was hardened, surface cleaned, and heat-treated for sintering to form a grid pattern of electrode patterns 130. At this time, each pattern line 131 of the electrode patterns 130 filled in each negative groove has the same width W and depth H. The silver (Ag) particles contained in the conductive paste include 30% of first particles 134 that are greater than or equal to 1 μm and less than or equal to 1.5 μm, and 70% of second particles 135 that are greater than or equal to 400 nm and less than or equal to 450 nm.

[0093] Furthermore, for performance comparison, a conventional shielding film (comparative example) was manufactured. This conventional shielding film has the same substrate, resin layer, and electrode pattern structure as the electromagnetic wave shielding film 100 according to the first embodiment of the present invention. That is, the electrode pattern of the comparative example is manufactured by pressing and filling conductive paste using the same mold, and therefore has the same grid pattern as the first embodiment. However, the electrode pattern was formed using conductive paste containing silver (Ag) particles with a size greater than or equal to 200 nm and less than or equal to 250 nm. In other words, in the comparative example, the electrode pattern was formed using silver (Ag) particles of approximately the same size.

[0094] exist Figure 7 and Figure 8 The first embodiment shows an electromagnetic wave shielding film 100 manufactured according to the first embodiment of the present invention, and the comparative example shows an electromagnetic wave shielding film manufactured in the prior art.

[0095] Reference Figure 7 As can be seen from the cross-sectional and enlarged views of the electrode pattern, the first embodiment includes a first structure 136A, while the comparative example only includes a second structure 136B and does not include the first structure 136A. That is, the electrode pattern 130 of the first embodiment contains metal particles, wherein large-sized first particles 134 are located between small-sized second particles 135, and the second particles 135 surround the first particles 134.

[0096] That is, the metal particles in the electrode pattern 130 have different sizes. In particular, when the mixing ratio of the large-sized first particle 134 to the small-sized second particle 135 is set to 3:7 as shown in the first embodiment, the silver (Ag) content in the same space is increased by about 4% compared to the comparative example. That is, it has been confirmed that the filling performance of the metal particles according to the first embodiment is improved. Furthermore, the surface resistance of the electrode pattern in the same region was measured. The results confirm that the first embodiment (approximately 0.4 Ω□, where □ represents the area in cm²) is significantly improved. 2 The resistance decreased by approximately 0.3 Ω compared to the comparative example (approximately 0.7 Ω □).

[0097] In summary, in the first embodiment, when the first particle 134 and the second particle 135 are mixed, the filling performance of the metal particles is improved, the filling weight density increases relatively, and thus the resistance can be relatively reduced.

[0098] Furthermore, for both the first embodiment and the comparative example, the shielding efficiency was measured for each frequency. That is, referring to... Figure 8It can be seen that the curve of the first embodiment has a higher shielding efficiency overall across all frequency bands than that of the comparative example. In particular, in the curve of the first embodiment, the electromagnetic wave shielding efficiency increases significantly in the high-frequency band, increasing by approximately 3 dB more than in the curve of the comparative example. That is, it can be seen that, similar to the first embodiment, the filling performance of the electrode pattern 130 formed by mixing large and small metal particles within a predetermined range is improved, resulting in reduced resistance and increased electromagnetic wave shielding efficiency across all frequency bands.

[0099] Figure 9 A partial cross-sectional view of one side of an electromagnetic wave shielding film 200 according to a second embodiment of the present invention is shown.

[0100] The electromagnetic wave shielding film 200 according to the second embodiment of the present invention has electromagnetic wave shielding performance, such as... Figure 9 As shown, it may include: a substrate 210, a resin layer 220, an electrode pattern 230, a conductive layer 240, and a hard coating layer 250. In this case, the substrate 210, resin layer 220, electrode pattern 230, and pattern lines 231 are the same as the substrate 110, resin layer 120, electrode pattern 130, and pattern lines 231 of the electromagnetic wave shielding film 100 according to the first embodiment of the present invention, as described above or later, and therefore their detailed description will be omitted. Of course, this electromagnetic wave shielding film 200 according to the second embodiment of the present invention can also be used as a screen device.

[0101] In particular, regardless of whether the electromagnetic waves generated by the electronic device are in the low-frequency or high-frequency band, the electromagnetic wave shielding film 200 according to the second embodiment of the present invention has high electromagnetic wave shielding performance, which can be achieved by additionally providing a highly conductive layer 240 on its top or bottom.

[0102] That is, the conductive layer 240 is a layer made of conductive material and may have an area covering the area of ​​the electrode pattern 230 arranged along one surface of the substrate 210. (Refer to...) Figure 9 The conductive layer 240 can be formed in the orientation of one surface of the electrode pattern 230 (see [reference]). Figure 9 (a) in the figure), or the direction formed on another surface of substrate 210 (see [reference]). Figure 9 (b)). Furthermore, the conductive layer 240 can be formed both on one surface of the electrode pattern 230 and on the other surface of the substrate 210.

[0103] For example, the conductive layer may include, but is not limited to, ITO, silver (AG) nanotubes, graphene, carbon nanotubes, silver (Ag) particles, or conductive polymers such as PEDOT:PSS (poly(3,4-ethylenedioxythiophene)polystyrene sulfonic acid). Furthermore, the screen device may be made of a transparent conductive material such as ITO to allow images to be displayed through it.

[0104] For example, the thickness of the conductive layer 240 can be approximately 80 μm or greater and less than or equal to 200 μm. In this case, the surface resistance is preferably approximately 50 Ω□ or greater and approximately less than or equal to 200 Ω□. More preferably, when the surface resistance is approximately 100 Ω□ or greater and approximately less than or equal to 150 Ω□, optimal electromagnetic wave shielding performance can be achieved. However, since the conductive layer 240 can be made of a material with high conductivity, the degree of electromagnetic wave reflection can be further improved, thereby further improving the electromagnetic wave shielding efficiency.

[0105] On the other hand, a hard coating 250 can be formed on the other surface of the substrate 210. This hard coating 250 is used to prevent scratch damage to the substrate 210 and can be applied selectively. That is, when the conductive layer 240 is formed on the other surface of the substrate 210 (see...) Figure 9 In (b) of the above, the conductive layer 240 may be formed on another surface of the hard coating 250.

[0106] Figure 10 The electromagnetic shielding efficiency curves of an electromagnetic wave shielding film 200 according to a second embodiment of the present invention, and its comparative examples, at different frequencies are shown.

[0107] On the other hand, an electromagnetic wave shielding film 200 according to a second embodiment of the present invention was manufactured for performance testing. Specifically, in Figure 7 and Figure 8 In the first embodiment manufactured in the first embodiment, a conductive layer 240 is also formed. That is, an ITO conductive layer 240 with a surface resistance of approximately 150 Ω·cm is deposited on one side of the electromagnetic wave shielding film 100 of the first embodiment. Figure 10 The second embodiment illustrates a manufactured electromagnetic wave shielding film 200 according to a second embodiment of the present invention. Furthermore, for performance comparison, a film used in… Figure 7 and 8 A comparative example manufactured in China.

[0108] For the second embodiment and the comparative example, the shielding efficiency was measured for each frequency. That is, referring to... Figure 10 It can be seen that, compared with the electromagnetic wave shielding film of the comparative example, the shielding efficiency of the electromagnetic wave shielding film 200 of the second embodiment is increased by at least about 4 dB to at most about 20 dB. In particular, it can be confirmed that the electromagnetic wave shielding efficiency is significantly improved in the low frequency band.

[0109] That is, the electromagnetic wave shielding film 200 according to the second embodiment of the present invention includes an electrode pattern 230, in which metal particles with large-sized first particles 134 and small-sized second particles 135 are mixed. By further including a conductive layer 240, the electromagnetic wave shielding film 200 can have a uniformly high shielding rate in both low-frequency and high-frequency bands.

[0110] Figure 11 An example is shown of an electromagnetic wave shielding film 100 according to a first embodiment of the present invention being used as a screen device in a display.

[0111] The screen device according to an embodiment of the present invention, as a light-transmitting screen device, includes an electromagnetic wave shielding film 100 according to the first embodiment of the present invention to achieve at least one of touch input and electromagnetic wave shielding. Furthermore, the screen device according to an embodiment of the present invention not only includes the electromagnetic wave shielding film 100 according to the first embodiment of the present invention, but may also include a protective substrate 30, a connector 40, and peripheral wiring 50. Such a screen device may include multiple sets (e.g., two sets) of protective substrates 30, connectors 40, and peripheral wiring 50, and these may be stacked and joined in the vertical direction.

[0112] This screen device according to an embodiment of the present invention can be disposed on the front of a display, can be used in a variety of ways as at least one of a touch screen device and an electromagnetic wave shielding device, and can also be applied to vehicle windows or building windows.

[0113] In this configuration, substrate 110 can be made of a transparent material that allows light to pass through, and the lower surface of substrate 110 can be stacked on the display panel. Electrode patterns 130, connectors 40, and peripheral wiring 50 can be formed on the upper surface of substrate 110, and a protective substrate 30 can protect their upper surfaces. The upper surface of the protective substrate 30 can be protected by a glass substrate (not shown). The area of ​​substrate 110 can be larger than the area of ​​the screen of the display to which the screen device is to be applied, or the same as the area of ​​the screen described above.

[0114] On the other hand, when used as a touch sensor, the area on the substrate 110 where the electrode pattern 130 is formed can be a channel region, a touch region, or an active region, and the remaining area can be a peripheral region. The channel region can include multiple channel intervals C. The electrode pattern 130 formed in each channel interval C can be electrically insulated from the electrode pattern 130 inside adjacent channel intervals C by means of disconnection or the like. That is, multiple disconnected lines separating and dividing the aforementioned channels along a predetermined direction can be formed in the electrode pattern 130 to form multiple electrically conductive channels. These disconnected lines represent portions disconnected at the periphery of each channel. Furthermore, the shape and arrangement of the channel intervals C can vary considerably.

[0115] Furthermore, the electrode pattern 130 of the electromagnetic wave shielding film 100 may include a plurality of irregular polygons 133. In addition, the spacing value P of each of the plurality of irregular polygons 133 is contained within a preset range, and adjacent irregular polygons 133 have different spacing values ​​P from each other.

[0116] The protective substrate 30 can be formed to cover the upper surface of the electromagnetic wave shielding film 100. The protective substrate 30 can have a thin film shape. The protective substrate 30 can include an optically clear adhesive (OCA) material and can be optically transparent. This protective substrate 30 can also be referred to as a protective sheet, adhesive sheet, or adhesive film.

[0117] Connector 40 and peripheral wiring 50 can be formed on the peripheral area of ​​transparent substrate 110. Connector 40 can be electrically connected to electrode pattern 130, and peripheral wiring 50 can connect connector 40 to external circuitry (not shown). Touch signals detected by electrode pattern 130 can be transmitted to external circuitry via connector 40. The connector 40 and peripheral wiring 50 can include at least one of indium tin oxide (ITO), copper (Cu), and silver (Ag) materials.

[0118] Of course, such a screen device may include an electromagnetic wave shielding film 200 according to the second embodiment of the present invention in place of the electromagnetic wave shielding film 100 according to the first embodiment of the present invention. However, its description will be omitted.

[0119] The screen device according to an embodiment of the present invention will be described in detail below.

[0120] In the following text, reference will be made to Figure 4 The first embodiment of the present invention describes in detail the plurality of irregular polygons 133 included in the electrode pattern 130. However, these descriptions can also be applied succinctly to the electrode pattern 230 according to the second embodiment of the present invention.

[0121] Each of the multiple irregular polygons 133 may have four or more vertices V. For example, the irregular polygon 133 may be a polygon with more than four sides. For example, when comparing a triangular irregular polygon with an irregular polygon with more than four sides that has the same spacing value, the area of ​​the triangular irregular polygon is smaller than the area of ​​the irregular polygon with more than four sides, and since the triangular irregular polygon is not large enough compared to the pixel area of ​​the display, optical interference may occur between the pixel and the triangular irregular polygon. When the irregular polygon 133 is formed as a polygon with more than four sides, since its area is larger than the same pixel value, optical interference between the irregular polygon 133 and the pixel can be suppressed or prevented.

[0122] The irregular polygon 133 can be a quadrilateral, pentagon, hexagon, or other shapes. The embodiments of the present invention will be described in detail below based on the pentagonal irregular polygon 133.

[0123] For example, an irregular polygon 133 having five vertices V and five sides S has a first vertex, a second vertex, a third vertex, a fourth vertex, and a fifth vertex, and includes a first side, a second side, a third side, a fourth side, and a fifth side. The extension directions r of each side S of this irregular polygon 133 can be different from each other. That is, the first direction of the first side extension, the second direction of the second side extension, the third direction of the third side extension, the fourth direction of the fourth side extension, and the fifth direction of the fifth side extension can be different directions. Furthermore, the angle θ formed by the adjacent sides S of the irregular polygon 133 around each vertex V can be different from each other. Therefore, it is possible to fundamentally prevent the boundary lines between the irregular polygons 133 from appearing more prominent than the surrounding area while forming a predetermined pattern. For example, when the irregular polygon 133 is too irregular, a foreign object sensation may appear on the electrode pattern 130, but the irregular polygon 133 according to the first embodiment of the present invention can fundamentally prevent a foreign object sensation.

[0124] On the other hand, the distance values ​​between the vertices V of the irregular polygon 133 can be different from each other within a predetermined size range. That is, the distance values ​​between the first and second vertices, the second and third vertices, the third and fourth vertices, the fourth and fifth vertices, and the fifth and first vertices are all included within the predetermined size range, and their sizes can be different from each other. Therefore, it is possible to prevent the shape of each irregular polygon 133 from being significantly skewed compared to its surroundings, and it is possible to suppress or prevent the irregular polygon 133 from protruding compared to its surroundings. The multiple irregular polygons 133 formed as described above can have different shapes between adjacent irregular polygons 133. Specifically, the first irregular polygon 133a and the second irregular polygon 133b that are adjacent to each other can have different shapes. In this case, the spacing value Pa of the first irregular polygon 133a and the spacing value Pb of the second irregular polygon 133b can be different from each other. The spacing values ​​P, Pa, and Pb represent the maximum values ​​among the distance values ​​between the vertices V of the irregular polygon 133.

[0125] The spacing value P of each of the plurality of irregular polygons 133 can be determined based on the transmittance and surface resistance of the electrode pattern 130. Specifically, the spacing value P of each of the plurality of irregular polygons 133 can be determined such that the transmittance of the electrode pattern 130 reaches 80% or more and the surface resistance of the electrode pattern 130 reaches 10Ω / cm. 2 For example, the lower limit of the spacing value of the irregular polygon 133 can be any value selected from that which makes the light transmittance of the electrode pattern 130 reach about 80% or more, and the upper limit can be selected from that which makes the surface resistance of the electrode pattern 130 reach about 10 Ω / cm. 2 Any of the following values. The upper limit of the transmittance of electrode pattern 130 is approximately less than 100%, and the lower limit of the surface resistivity of electrode pattern 130 can be approximately 0.1 Ω / cm. 2 As stated above, the lower and upper limits of the spacing value P of the irregular polygon 133 can be selected within a range of approximately greater than or equal to 70 μm and approximately less than or equal to 650 μm.

[0126] On the other hand, the lower limit of the spacing value P of the plurality of irregular polygons 133 can be approximately 70% of the reference spacing value, and the upper limit can be approximately 130% of the reference spacing value. That is, the upper and lower limits of the plurality of irregular polygons 133 can be determined based on the predetermined reference spacing value; therefore, the plurality of irregular polygons 133 can have a deviation of approximately ±30% compared to the predetermined reference spacing value. Specifically, relative to the reference spacing value, the minimum spacing value can have a deviation of approximately -30%, and the maximum spacing value can have a deviation of approximately +30%. That is, the upper and lower limits of the spacing values ​​of the plurality of irregular polygons 133 can be determined by the reference spacing value. In other words, the reference spacing value refers to the spacing value that serves as a reference when determining the upper and lower limits of the spacing values.

[0127] For example, among the spacing values ​​of multiple irregular polygons 133, the minimum spacing value can be 0.7 times the reference spacing value, and the maximum spacing value can be 1.3 times the reference spacing value. Therefore, it is possible to prevent the size of each irregular polygon 133 from protruding significantly from its surroundings, and to suppress or prevent non-specific irregular polygons 133 from protruding from their surroundings.

[0128] In other words, if the upper and lower limits of the reference spacing values ​​exceed the aforementioned deviations, when an irregular polygon with the minimum spacing value is adjacent to an irregular polygon with the maximum spacing value, its boundary will appear to protrude more than its surroundings due to the size difference between them, thus creating a sense of incongruity. Conversely, if the deviations of the upper and lower limits of the reference spacing values ​​are within the aforementioned range, even if an irregular polygon with the minimum spacing value is adjacent to an irregular polygon with the maximum spacing value, its boundary will not appear to protrude more than its surroundings, and therefore will not create a sense of incongruity.

[0129] The reference spacing value can be determined to be the same as or similar to the pixel size of the display of the application screen device within a predetermined spacing value range. For example, the minimum and maximum spacing values ​​determined by the reference spacing value are such that the light transmittance of the electrode pattern 130 reaches about 80% or more and the surface resistance reaches about 10 Ω / cm. 2 Within the following range of spacing values: When the transmittance of the electrode pattern 130 is less than approximately 80%, it becomes difficult to accurately identify the image output from the display device positioned below the electrode pattern 130. When the surface resistance of the electrode pattern 130 exceeds approximately 10 Ω / cm... 2 When this happens, the touch recognition sensitivity of the electrode pattern 130 will decrease.

[0130] The aforementioned reference spacing value can be any value selected from approximately 100 μm or greater and approximately 500 μm or less. In this case, when the reference spacing value is less than approximately 100 μm, the minimum spacing value may be less than approximately 70 μm, and the transmittance of the electrode pattern 130 may be reduced to less than approximately 80% due to the irregular polygons with the minimum spacing value. When the reference spacing value exceeds approximately 500 μm, the maximum spacing value may exceed approximately 650 μm, and the surface resistance of the electrode pattern 130 may be greater than approximately 10 Ω / cm due to the irregular polygons with the maximum spacing value. 2 On the other hand, the larger the spacing value P among the multiple irregular polygons 133, the higher the light transmittance of the electrode pattern 130. Furthermore, the smaller the spacing value P among the multiple irregular polygons 133, the lower the surface resistance of the electrode pattern 130 may be.

[0131] Therefore, in the irregular polygon 133, the size of the reference spacing value and the range of the spacing value P can be determined as described above based on the required transmittance and surface resistance of the electrode pattern 130, and the transmittance and surface resistance of the electrode pattern 130 containing the irregular polygon 133 can be maintained at a desired high level. On the other hand, when the transmittance of the electrode pattern 130 deteriorates, the screen device has difficulty accurately recognizing the image output from the display, and when the surface resistance of the electrode pattern 130 increases, the touch recognition sensitivity may decrease.

[0132] As described above, when some non-specific portions of the irregular polygons 133 constituting the electrode pattern 130 are relatively larger or smaller in size than their surroundings, that portion may appear more prominent than its surroundings. Therefore, the range of the spacing value P of the irregular polygons 133 according to the first embodiment of the present invention is specifically exemplified below.

[0133] (Example 1)

[0134] The lower limit of the spacing value P of the irregular polygons 133 is approximately 70 μm, and the upper limit is approximately 130 μm. In this case, the reference spacing value can be approximately 100 μm. The shape or size of each irregular polygon 133 can be determined within these spacing values ​​P. Therefore, multiple irregular polygons 133 can have various spacing values ​​P that differ from each other within a spacing value P range of approximately greater than or equal to 70 μm and approximately less than or equal to 130 μm. This prevents the irregular polygons 133 from becoming excessively irregular and fundamentally prevents the formation of a predetermined shape with specific regularity in the electrode pattern 130.

[0135] (Example 2)

[0136] The lower limit of the spacing value P of the plurality of irregular polygons 133 is approximately 140 μm, and the upper limit is approximately 260 μm. In this case, a reference spacing value can be approximately 200 μm. The shape or size of each irregular polygon 133 can be determined within these spacing values ​​P. That is, the plurality of irregular polygons 133 constituting the electrode pattern 130 can have various spacing values ​​P that differ from each other within a spacing value P range of approximately greater than or equal to 140 μm and approximately less than or equal to 260 μm.

[0137] (Example 3)

[0138] The lower limit of the spacing value P of the irregular polygons 133 is approximately 210 μm, and the upper limit is approximately 390 μm. In this case, a reference spacing value can be approximately 300 μm. The shape or size of each irregular polygon 133 can be determined within these spacing values ​​P. That is, the plurality of irregular polygons 133 constituting the electrode pattern 130 can have various spacing values ​​P that differ from each other within a spacing value P range of approximately greater than or equal to 210 μm and approximately less than or equal to 390 μm.

[0139] (Example 4)

[0140] The lower limit of the spacing value P of the irregular polygons 133 is approximately 245 μm, and the upper limit is approximately 455 μm. In this case, a reference spacing value can be approximately 350 μm. That is, the plurality of irregular polygons 133 constituting the electrode pattern 130 can have various spacing values ​​P that differ from each other within a spacing value P range of approximately 245 μm or greater and approximately 455 μm or less. When the range of spacing values ​​P of the plurality of irregular polygons 133 exceeds the above range, when irregular polygons with a spacing value P less than approximately 245 μm are adjacent to irregular polygons with a spacing value P greater than approximately 455 μm, a foreign object sensation may occur in the electrode pattern 130 due to the size difference between them.

[0141] (Example 5)

[0142] The lower limit of the spacing value P of the irregular polygons 133 is approximately 280 μm, and the upper limit is approximately 520 μm. In this case, a reference spacing value can be approximately 400 μm. The shape or size of each irregular polygon 133 can be determined within these spacing values ​​P. That is, the plurality of irregular polygons 133 constituting the electrode pattern 130 can have various spacing values ​​P that differ from each other within a spacing value P range of approximately greater than or equal to 280 μm and approximately less than or equal to 520 μm. When the range of the spacing values ​​P of the plurality of irregular polygons 133 exceeds the above range, when irregular polygons with a spacing value P less than approximately 280 μm are adjacent to irregular polygons with a spacing value P greater than approximately 520 μm, a foreign object sensation may occur in the electrode pattern 130 due to the size difference between them.

[0143] (Example 6)

[0144] The lower limit of the spacing value P of the irregular polygons 133 is approximately 315 μm, and the upper limit is approximately 585 μm. In this case, a reference spacing value can be approximately 450 μm. That is, the plurality of irregular polygons 133 constituting the electrode pattern 130 can have various spacing values ​​P that differ from each other within a spacing value P range of approximately greater than or equal to 315 μm and approximately less than or equal to 585 μm. If the spacing value P of the plurality of irregular polygons 133 exceeds the above range, the electrode pattern 130 may produce a foreign body sensation.

[0145] (Example 7)

[0146] The lower limit of the spacing value P of the irregular polygons 133 is approximately 350 μm, and the upper limit is approximately 650 μm. In this case, a reference spacing value can be approximately 500 μm. The shape or size of each irregular polygon 133 can be determined within these spacing values ​​P. That is, the multiple irregular polygons 133 constituting the electrode pattern 130 can have various spacing values ​​P that differ from each other within a spacing value P range of approximately greater than or equal to 350 μm and approximately less than or equal to 650 μm. If the spacing value P of the multiple irregular polygons 133 exceeds the above range, the electrode pattern 130 may produce a foreign body sensation.

[0147] As described above, the reference spacing value can be selected from 100 μm to 500 μm, and the range of spacing values ​​P of the multiple irregular polygons 133 can be determined based on the aforementioned reference spacing value, due to the electrical and optical characteristics of the touchscreen device formed by the grid. The touchscreen device should ensure a transmittance greater than or equal to a predetermined value at the top of the display device and requires low surface resistance to achieve high touch sensitivity.

[0148] The transmittance and surface resistance in the grid depend on the spacing value. Typically, the spacing value, transmittance, and surface resistance of the electrode pattern 130 are proportional. When the reference spacing value of the electrode pattern 130 is approximately 100 μm, the transmittance is approximately 80%, and the surface resistance is approximately 1 Ω□. Furthermore, when the reference spacing value of the electrode pattern 130 is approximately 500 μm, it has approximately 87% transmittance and approximately 7 Ω□ of surface resistance. From the above, it can be confirmed that as the spacing value increases, the transmittance improves; however, due to the correspondingly increased surface resistance, the touch sensitivity may be lower than that of a grid with a smaller spacing.

[0149] Furthermore, by distributing the irregular polygons 133 within a predetermined range at a spacing value P, it is possible to prevent irregular polygons 133, which are larger or smaller than their surroundings, from appearing or clustering in unspecified areas of the electrode pattern 130, thereby preventing the unspecified areas of the electrode pattern 130 from appearing to protrude from their surroundings. That is, it is possible to prevent a foreign object sensation at the boundaries of the irregular polygons 133 due to size differences. At this time, since the surface resistance of the electrode pattern 130 is smaller as the reference spacing value approaches approximately 100 μm, touch sensitivity can increase, and since the light transmittance is greater as the reference spacing value approaches approximately 500 μm, the screen brightness of the display of the screen device can be increased.

[0150] On the other hand, the shape of the electrode pattern 130 formed as described above can be designed using, for example, a predetermined design program. However, designing the entire shape of the electrode pattern 130 at once using the predetermined design program would result in a considerable computational load. Therefore, referring to... Figure 11 The electrode pattern 130 according to the first embodiment of the present invention may include a plurality of unit grid blocks A that are arrayed together.

[0151] That is, in the embodiments of the present invention, the entire area of ​​the electrode pattern 130 can be divided into unit grid blocks A of the same size. The shape of the grid pattern is designed for the unit grid A of the blocks, and the shape of an electrode pattern 130 connected to each other can be formed by arranging the designed shapes. At this time, the size of the multiple unit grid blocks A can be determined according to, for example, the number of grid objects in the block. The number of grid objects in the block is determined according to the number of grids (polygons) in the block, and in this case, the suitable number of objects is approximately greater than or equal to 40,000 and approximately less than or equal to 250,000. When this number of objects is achieved with square-shaped blocks, the block size can be up to 5cm × 5cm. Specifically, the block size can be greater than or equal to 1cm × 1cm and less than or equal to 5cm × 5cm. For example, the block size can be selected in the range of greater than or equal to 1cm × 1cm and less than or equal to 5cm × 5cm. Of course, the block size can vary widely in the range of less than or equal to 5cm × 5cm.

[0152] The shape of this block uses a square shape that optimizes the side length per unit area; however, quadrilaterals of other shapes can also be used. The appropriate number of objects and block sizes is determined based on the computational capabilities of a standard design PC. Exceeding these appropriate numbers may cause problems during the design process.

[0153] At this point, to prevent the boundary of unit grid block A from becoming visible, the irregular polygons forming the boundary between unit grid blocks A on the outermost side of each of the multiple unit grid blocks A can have different shapes and sizes from each other. That is, the shape and size of the irregular polygons forming the boundary of the multiple unit grid blocks A can be corrected.

[0154] Specifically, the shape and size of the edges S of the irregular polygons 133 located at the boundary of unit grid block A can be corrected so that their lengths and their extension directions r are different from each other, and the shape of the irregular polygons 133 can be corrected so that the angles θ formed by adjacent edges S with each vertex V as the center are different from each other. This correction is called block boundary line correction, which can fundamentally prevent the creation of an unnatural feeling at the boundary of unit grid block A, and allow the individual unit grid blocks A to be arranged naturally or smoothly. That is, depending on the computing power of the design PC, since it is difficult to complete the design of the overall shape of the electrode pattern 130 at once, it is necessary to design the shape of the unit grid blocks A separately and then arrange them into the shape of an electrode pattern 130.

[0155] At this point, if the block boundary lines are not corrected, even if the spacing values ​​of the irregular polygons 133 adjacent to each other within each unit grid block A are different, it is possible that the spacing values ​​of the irregular polygons 133 adjacent to each other will be the same at the boundary of unit grid block A. Therefore, the boundary of unit grid block A may be visible.

[0156] On the other hand, when the shapes of the unit grid blocks A are designed separately and then arranged to design the shape of an electrode pattern 130, if block boundary line correction is performed, the spacing values ​​of the irregular polygons 133 that are adjacent to each other on all surfaces of the electrode pattern 130 can be different from each other. Therefore, the boundaries of the unit grid blocks A can be prevented from being visible.

[0157] Figure 12 These are photographs comparing and illustrating electrode patterns according to embodiments and comparative examples of the present invention. Figure 12 (a) shows an electrode pattern according to a comparative example of the invention, having a spacing range of approximately 70 μm and approximately 130 μm, and a grid line width and depth of approximately 10 μm. Since the block boundary lines are in an uncorrected state, at least some adjacent irregular polygons near the boundary of a unit grid block have the same spacing value. Observing the boundary lines of the grid pattern of the comparative example, it can be seen that relatively small irregular polygons are clustered together, and the shadows of straight lines on the grid pattern are visible due to these size differences.

[0158] on the contrary, Figure 12 Figure (b) shows an electrode pattern 130 according to an embodiment of the present invention, which has a spacing value range of approximately greater than or equal to 70 μm and approximately less than or equal to 130 μm, and the line width and depth of the grid lines are approximately 10 μm. Since the block boundary lines are in an uncorrected state, the spacing value of each of the irregular polygons adjacent to each other on all surfaces of the electrode pattern 130 is different from each other. As shown in the figure, the spacing values ​​of the plurality of irregular polygons 133 deviate from the reference spacing value by approximately ±30%, thus preventing the aggregation of irregular polygons throughout the grid pattern due to size differences, and confirming that the aforementioned aggregation does not occur at the boundaries between blocks. That is, in the embodiment of the present invention, it can be seen that no straight-line shadows are formed on the grid pattern.

[0159] On the other hand, the aforementioned boundary line refers to the boundary line of the unit grid block that forms the electrode pattern.

[0160] Figure 13 These are diagrams comparing and illustrating the characteristics of screen devices according to embodiments and comparative examples of the present invention. That is, Figure 13This is a table comparing and illustrating the light transmittance of screen devices according to embodiments and comparative examples of the present invention. Light transmittance refers to the transmittance of light intensity through the screen device; the larger the size of the screen device, the better its ability to transmit light.

[0161] Figure 13 The comparative example shows a grid pattern of irregular polygons without using reference spacing values ​​to limit the upper and lower limits of the spacing values. The center value of the spacing values ​​of the grid pattern is about 100 μm and the range of the spacing values ​​is within a predetermined range that is greater than or equal to about 70 μm and less than or equal to about 130 μm. The grid pattern includes irregular polygons with a line width and depth of about 10 μm. Figure 13 The embodiments illustrate a grid pattern of irregular polygons with upper and lower limits for the spacing values ​​defined by reference spacing values. The spacing value of the grid pattern is about 100 μm, and the spacing value ranges from about 70 μm to about 130 μm. The grid pattern includes irregular polygons with a line width and depth of about 10 μm for the grid lines.

[0162] Comparison includes based on Figure 13 The transmittance of the screen device with the electrode pattern of the comparative example and the screen device including the electrode pattern according to the embodiment shows that the transmittance of the comparative example is less than 84%, while the transmittance of the embodiment is greater than 84%. In other words, it can be seen that the transmittance of the embodiment is higher. This means that the screen device of the embodiment can better transmit the image of the display.

[0163] The reason for the aforementioned difference in transmittance between the comparative example and the embodiment is that, in the comparative example, due to the large difference between the upper and lower limits of the spacing value, the irregular polygon with a relatively small spacing value appears more prominent compared to its surroundings, and this portion produces a shadow that deepens. The interference between this shadow and the pixel pattern of the display forms moiré fringes. In contrast, in the first embodiment, the upper and lower limits of the spacing value are defined to have a deviation of approximately ±30% compared to the reference spacing value. As the spacing value is distributed differently within the defined range, while eliminating the repetition of regular shapes within the electrode pattern, excessive irregularity can be prevented, thereby fundamentally preventing moiré fringes caused by size differences and maintaining good visibility.

[0164] Figure 14 These are images used to illustrate whether moiré patterns appear in a screen device according to an embodiment of the present invention. Figure 15 These are images illustrating a display using a screen device according to an embodiment of the present invention. Figure 14 The darker area represents the bezel of the display device, and the lighter area inside this dark bezel represents the screen of the monitor. Figure 14These are images of a display taken using a screen device according to an embodiment of the present invention.

[0165] In the comparative example, the Moiré effect may be exacerbated depending on how the angle is determined on the display, because irregular polygons may cluster at irregular locations within the electrode pattern and potentially create shadows. In contrast, in the embodiment, it is possible to fundamentally prevent irregular polygons from clustering at irregular locations within the grid pattern or creating shadows, thus... Figure 14 As shown, even when the screen device is superimposed on the display, no moiré interference fringes appear. Therefore, as Figure 15 As shown in the embodiments of the present invention, even with a 360-degree rotating screen device, moiré effects can be avoided in all directions, thereby ensuring good visibility.

[0166] The electromagnetic wave shielding films 100 and 200 according to the present invention, having the structure described above, have improved shielding performance. That is, the electromagnetic wave shielding films 100 and 200 according to the present invention can not only exert improved electromagnetic wave shielding performance in any frequency band of electromagnetic waves generated from the application product, but also can comprehensively shield electromagnetic waves of various frequency bands generated from complex products or various fields with a high shielding rate without being limited by frequency band.

[0167] Furthermore, when the electrode patterns 130 and 230 of the electromagnetic wave shielding films 100 and 200 according to the present invention include irregular polygons 133, interference with the pixel patterns of the display can be prevented, thereby avoiding moiré effects at all angles of the plane and achieving improved visibility. Moreover, these irregular polygons 133 can suppress pattern aggregation of the electrode patterns 130 and 230, making the distribution of the electrode patterns 130 and 230 more balanced, thereby further improving the electromagnetic wave shielding effect.

[0168] Specifically, since the multiple irregular polygons 133 are polygonal shapes with at least four sides and different from each other, the visibility of boundary lines can be solved from all 360 degrees while meeting the optical and electrical characteristics required by the screen device, and the moiré effect can be avoided. Therefore, when the screen device is attached to the front of the display device and used as a touch screen device or an electromagnetic wave shielding device, the moiré effect caused by the foreign object sensation of the grid pattern can be fundamentally prevented. Furthermore, by preventing the pixel pattern of the display device from interfering with the electrode pattern 130 of the screen device from all angles of the display without being affected by the pixel pattern, the moiré effect can be avoided from all 360 degrees and the visibility of the screen device can be improved.

[0169] While specific embodiments have been described in the invention summary, various modifications can naturally be made without departing from the scope of the invention. Therefore, the scope of the invention is not limited to the described embodiments, but should be defined by the appended claims and their equivalents.

[0170] Industrial availability

[0171] This invention relates to an electromagnetic wave shielding film. Since it can provide an electromagnetic wave shielding film with improved electromagnetic wave shielding efficiency and high electromagnetic wave shielding performance in all frequency bands of electromagnetic waves, this invention has industrial applicability.

Claims

1. An electromagnetic wave shielding film, wherein, include: substrate; The electrode pattern is disposed on one surface of the substrate and contains metal particles; as well as A transparent conductive layer is disposed on one surface of the electrode pattern and covers the electrode pattern arranged along one surface of the substrate. The surface resistivity of the transparent conductive layer is 150 Ω / mm², and the transparent conductive layer is made of indium tin oxide (ITO). The metal particles each comprise a first particle having a size within a first range and a second particle having a size within a second range smaller than the first range, wherein the number of second particles is greater than the number of first particles, and at least one first particle is mixed among the second particles. The size of the first range is greater than or equal to 1 μm and less than or equal to 1.5 μm; the size of the second range is greater than or equal to 400 nm and less than or equal to 450 nm. The ratio of the number of the first particle to the number of the second particle is 3:

7. The electrode pattern is formed in a grid pattern shape, the grid pattern shape comprising a plurality of polygons arranged along one surface of the substrate. The plurality of polygons includes a plurality of irregular polygons that are adjacent to each other, wherein the spacing values ​​of the adjacent irregular polygons are different from each other. The spacing between the plurality of irregular polygons is greater than or equal to 70 μm and approximately less than or equal to 130 μm. The irregular polygon has four or more vertices, and the directions of extension of each side are different from each other. In the irregular polygon, the angles formed by the edges adjacent to each other with each vertex as the center are different. The width and depth of the electrode pattern lines are greater than or equal to 4 μm and approximately less than or equal to 10 μm.

2. The electromagnetic wave shielding film according to claim 1, wherein, The electrode pattern includes a first structure in which a plurality of second particles surround the first particle.

3. The electromagnetic wave shielding film according to claim 2, wherein, The electrode pattern also includes a second structure, which is composed of multiple second particles connected together.

4. The electromagnetic wave shielding film according to claim 3, wherein, The electrode pattern includes more second structures than the first structure.

5. The electromagnetic wave shielding film according to claim 1, wherein, The electrode pattern is formed along a groove, which is formed on one surface of the substrate or on one surface of a resin layer disposed on one surface of the substrate.

6. The electromagnetic wave shielding film according to claim 1, wherein, The metal particles are selected from any one of silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), and chromium (Cr).

7. The electromagnetic wave shielding film according to claim 1, wherein, The substrate is a transparent substrate, and therefore can be used as a light-transmitting screen device for a display.

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