JP2006210763A - Electromagnetic wave shield filter for display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic wave shield filter for display which has thin lines that are formed into a meshy pattern so as to ensure conductivity and light transmittance, and that are hardly break and easily manufactured. <P>SOLUTION: At least a conductive mesh layer 2 having a mesh 2A of a mesh pattern in a plan view is formed on a transparent base material 1 to form the electromagnetic wave shield filter 10 for display. The mesh pattern of the mesh layer 2 is formed in such a way that a line width W is 50 to 100μm, and a line pitch P is 500 to 1,000μm, and the mesh size is determined as a diagonal dimension L of 800 mm or larger. The line width W is relatively large, but the diagonal dimension L is 800 mm or larger. Accordingly, the size gives a mesh part for use in a relatively large display. The lines are, therefore, not so conspicuous when they are seen from a ceratin distant place for watching the display. If the mesh layer 2 on the transparent base material 1 is covered with a colored filter layer at the display observer side, the lines become preferably less conspicuous. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electromagnetic wave shielding filter for a display disposed on the front surface of various displays such as a PDP (plasma display panel).

  Conventionally, a display is typically a CRT (CRT) display, but recently, a flat panel display (FPD) has been widely used as a thin TV or the like. Among FPDs, LCD (Liquid Crystal Display) and PDP (Plasma Display Panel) are pioneering, but in the future, SED (Surface-Production Electron-Emitter Display) will be used in addition to these. The spread of FED (Field Emission Display), which attracts attention, is also expected.

  In such various displays, electromagnetic waves are generated from pixel drive signals and so on. For example, in the case of PDP and CRT, the electromagnetic waves generated from these displays are shielded on the front of the display. An electromagnetic shielding filter is known. The electromagnetic wave shielding filter used for such applications requires light transmittance as well as electromagnetic wave shielding performance. Thus, a transparent substrate such as a resin film or glass is used as the substrate, and an electromagnetic wave for display provided with a mesh layer that achieves both electrical conductivity and light transmittance by etching or metal plating of a metal foil on the transparent substrate. A shield filter is known. Since the mesh layer made of a metal layer itself is light opaque, the layer is formed in a pattern so that the shape in plan view is a mesh shape, and a large number of small holes (openings) are provided so that light transmission is achieved. Is secured. However, if the mesh is too large, it will get in the way of the display image, and if the total area (opening ratio) of the mesh holes is small, the display image will also be disturbed and dark. However, if the lines that make up the mesh are made too thin, the area resistance of the mesh increases and disconnection or the like occurs, impairing the original electromagnetic shielding performance.

  Therefore, conventionally, the mesh shape of such a mesh layer is preferably set to have a size such as, for example, a line width W of a line constituting the mesh of 40 μm or less, a line pitch P of 200 μm or more, and the like. The aperture ratio of the mesh has been about 80% to 90% (for example, a mesh in which square openings are arranged in a square lattice, and the aperture ratio is K81% when the line pitch is 250 μm and the line width is 25 μm) (Patent Document 1). ).

  Also, if the surface of the mesh layer is light-reflective, unnecessary light such as outside light is reflected and the bright room contrast of the fluoroscopic image is lowered. Therefore, the surface of the mesh layer itself is usually blackened. It is also known that the blackened layer is blackened (Patent Document 1).

Japanese Patent No. 3388682

However, since the mesh of the mesh layer is composed of very thin lines with a line width of 40 μm or less, it is easy to break if care is not taken during manufacturing processing or after forming the mesh into a mesh shape, and the breakage is the manufacturing yield. It was a hindrance to the reduction and cost reduction.
That is, an object of the present invention is to provide an electromagnetic wave shielding filter for a display which is easy to manufacture because the mesh is hardly broken.

  In order to solve the above problems, an electromagnetic wave shielding filter for a display according to the present invention is for a display in which a conductive mesh layer having at least a mesh portion having a mesh shape in plan view is formed on a transparent substrate. In the electromagnetic wave shielding filter, the mesh shape of the mesh layer is such that the line width W is 50 to 100 μm, the line pitch P is 500 μm to 1000 μm, and the size of the mesh part is a diagonal dimension L of 800 mm or more. It was.

  By adopting such a configuration, the line width W is increased to 50 μm or more as compared with the conventional 40 μm or less, so that the line is not easily broken and the manufacture is facilitated. Moreover, the line width W is as thick as 50 μm or more, but the maximum is 100 μm, and the size of the mesh portion that ensures light transmission by the mesh is 800 mm or more in the diagonal dimension L. The mesh lines are inconspicuous from the distance of viewing such a large display because it is limited to those applicable to displays of a corresponding size or larger. Therefore, disconnection of the mesh can be prevented while ensuring the invisibility of the mesh.

Moreover, the electromagnetic wave shielding filter for a display according to the present invention has a configuration in which a colored filter layer is further provided so as to cover the mesh layer on the transparent substrate in the above configuration.
With such a configuration, in a method of application to a display in which the mesh layer side is an observer side with respect to the transparent base material, external light that has entered the electromagnetic wave shielding filter for display is reflected inside the colored filter layer. In order to reach the observer, it is necessary to pass through the colored filter layer twice in the forward path and in the return path, so that reflection of external light can be suppressed. As a result, reflection of external light from the line surface of the mesh layer is suppressed, and the line width W of the mesh layer is 50 μm, which is difficult to see even if it is thicker than in the past.

According to the electromagnetic wave shielding filter for a display according to the present invention, the mesh is difficult to be disconnected and the manufacturing becomes easy, and the manufacturing yield can be improved and the cost can be reduced.
Furthermore, if a colored filter layer is provided on the mesh layer on the transparent substrate, the mesh line can be made inconspicuous even if the mesh line is thick.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory view conceptually illustrating an electromagnetic wave shielding filter for a display according to the present invention in one form thereof, (A) is a cross-sectional view of a layer configuration, (B) is a partially enlarged plan view of a mesh shape, (C) is a whole top view which shows a mesh part and its diagonal dimension.
FIG. 2 is an explanatory diagram showing a desirable combination range of the line width W and the line pitch P.
FIG. 3 is a cross-sectional view illustrating two examples as a detailed configuration of the layer configuration of the mesh layer.
FIG. 4 is a cross-sectional view illustrating two examples as a configuration example having a colored filter layer.
FIG. 5 is a cross-sectional view illustrating three examples as additional layer configurations other than the transparent substrate and the mesh layer excluding the colored filter layer.

〔Overview〕
In the present invention, as in the electromagnetic wave shielding filter for display 10 illustrated in the cross-sectional view of FIG. 1A and the plan views of FIG. 1B and FIG. The mesh shape of the mesh layer 2 is such that the line width W of the mesh is 50 to 100 μm and the line pitch P is 500 μm to 1000 μm. The diagonal dimension L of the mesh part 2A, which is a region in which transparency is ensured, is set to a size of 800 mm or more. In addition, although the mesh layer 2 illustrated in FIG. 1C has the non-mesh portion 2B around the entire mesh portion 2A, the entire area of the electromagnetic wave shielding filter for display may be the mesh portion 2A. And by setting it as such a specific mesh layer, it becomes difficult to generate | occur | produce the disconnection of a line, without making the line of a mesh conspicuous. Further, for example, if the colored filter layer 3 is provided on the observer side of the mesh layer 2 on the transparent substrate 1 as shown in FIG. 4, the mesh can be made more inconspicuous.

In this specification, the term representing the surface and direction specifying the orientation, such as “front side”, “front side”, “back side”, “back side”, etc., is a mesh layer formed on a transparent substrate. The surface (also the upper surface in the drawing) that faces in the same direction as the side (referred to as “front side”) is referred to as “front side”, and “back side” and “back side” are the opposite, “front side” or “front side”. The surface whose direction is opposite to the surface is referred to as the “back surface”, and the opposite direction is referred to as the “back side”.
In addition, when applied to a display, the viewer side surface may always be the back surface instead of the front surface defined in the present invention. However, in the case where the colored filter layer is provided on the mesh layer as described above, it is preferable that the colored filter layer side is the surface on the viewer side. This is because the effect of making the mesh layer inconspicuous by the colored filter layer is obtained more than in the opposite case.

  Hereinafter, the electromagnetic wave shielding filter for display according to the present invention will be described in order from a transparent substrate.

(Transparent substrate)
The transparent substrate 1 is a layer for reinforcing a mesh layer generally having a low mechanical strength. Therefore, as long as it has light transmittance as well as mechanical strength, it may be selected and used depending on the application, taking into account heat resistance, insulation, etc. as appropriate. Specific examples of the transparent substrate include a resin plate, a resin sheet (or a film, the same applies hereinafter), a glass plate, and the like.

  Examples of transparent resins used as resin plates and resin sheets include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, terephthalic acid-isophthalic acid-ethylene glycol copolymer, and terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer. Polyester resins such as nylon 6, polyamide resins such as nylon 6, polyolefin resins such as polypropylene and polymethylpentene, acrylic resins such as polymethyl methacrylate, styrene resins such as polystyrene and styrene-acrylonitrile copolymer, triacetyl Examples thereof include cellulose resins such as cellulose, imide resins, and polycarbonate resins.

In addition, these resins are used as a single or a plurality of types of mixed resins (including polymer alloys) as a resin material, and as a layer, they are used as a single layer or a laminate of two or more layers. In the case of a resin sheet, a uniaxially stretched or biaxially stretched sheet is more preferable in terms of mechanical strength.
Moreover, you may add additives, such as a ultraviolet absorber, a near-infrared absorber, a filler, a plasticizer, an antistatic agent, suitably in these resin as needed.

  Further, as glass of the glass plate, there are quartz glass, borosilicate glass, soda lime glass, etc. More preferably, the thermal expansion coefficient is small, the dimensional stability and the workability in high-temperature heat treatment are excellent, and the alkali component in the glass Non-alkali glass that does not contain any of them can be used, and it can also be used as an electrode substrate as a front substrate of a display.

  The thickness of the transparent substrate is not particularly limited as long as it depends on the application. When the transparent substrate is made of a transparent resin, it is usually about 12 to 1000 μm, preferably 50 to 700 μm, more preferably 100. ˜500 μm is desirable. On the other hand, when a transparent base material is a glass plate, about 1-5 mm is usually suitable. In any material, if the thickness is less than the above, the mechanical strength is insufficient, causing warping, sagging, breakage, etc. If the thickness exceeds the above, it becomes excessive performance and high cost, and thinning is difficult. .

In addition, as a transparent base material, a sheet (or film), a plate, or the like made of these inorganic materials or organic materials can be applied, and the transparent base material is a display main body made of a front substrate, a back substrate, or the like. It may be combined with the front substrate, which is a component, but in the form of using the electromagnetic wave shielding filter for display as the front filter placed in front of the front substrate, the sheet is better than the plate in terms of thinness and lightness. Needless to say, the resin sheet is superior to the glass plate in that it is excellent and is not broken.
Moreover, it is preferable to handle a transparent base material with the form of a continuous strip | belt-shaped sheet | seat (namely, web) at the point which can manufacture the electromagnetic wave shield filter for displays continuously, and can improve productivity.

  In this respect, a resin sheet is a preferable material for the transparent substrate, but among the resin sheets, in particular, polyester resin sheets such as polyethylene terephthalate and polyethylene naphthalate, and cellulose resin sheets are transparent, In view of heat resistance, cost, etc., a polyethylene terephthalate sheet is more preferable. In addition, although the transparency of a transparent base material is so good that it is high, Preferably the light transmittance which becomes 80% or more by visible light transmittance | permeability is good.

  In addition, a transparent substrate such as a resin sheet is appropriately coated on the surface thereof with known easy processes such as corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer treatment, pre-heat treatment, dust removal treatment, vapor deposition treatment, and alkali treatment. An adhesion treatment may be performed.

  The transparent substrate may be colored with a pigment or the like. By coloring, near infrared absorption, neon light absorption, color adjustment, prevention of external light reflection, and the like can be achieved. For example, various conventionally known dyes such as a near-infrared absorber, a neon light absorber, a color adjusting dye, and an external light reflection preventing dye may be added to the transparent substrate of the resin.

[Mesh layer]
The mesh layer 2 is an area formed in a pattern so that the plan view has a mesh shape (this area is referred to as a mesh portion 2A). 1C], and a layer that secures light transmission as well as electromagnetic shielding properties by the mesh shape. In the present invention, the mesh shape of the mesh layer 2 and the size of the mesh portion are specified.

[Mesh layer: Mesh shape]
A typical mesh shape in a region (mesh portion 2A) in which the mesh layer 2 secures light transmittance by a large number of openings is illustrated in the partially enlarged plan view of FIG. The mesh shape shown in the figure shows a typical mesh shape having a square lattice shape in which the line width W is uniform in length and breadth, the opening _AO is square, and this is regularly arranged vertically and horizontally. Mesh has a plurality of openings A _O, opening A _O between the normal width uniformity linear line portion A _L, and the normally as further in FIG. 1 (B), opening A _O, and openings The line portion A _L between A _O has the same shape and the same size on the entire surface. That is, the openings A _O having a single shape are regularly arranged vertically and horizontally with a predetermined width (line width W) therebetween.

The meaning of the line width W of the line portion A _L and the line pitch P, which is the repetition period of the line portion A _L , which defines the shape of the mesh in plan view, is a cross-sectional view of FIG. 1A and FIG. As shown in the plan view of FIG. Therefore, in a mesh in which square openings are arranged in a square lattice as shown in FIG. 1B, the value obtained by subtracting the line width W from the line pitch P is the length of one side of the square (opening width). )
Note that the mesh opening ratio K [%] is the ratio of the area occupied by all openings (in the mesh portion) to the total area (of the mesh portion provided with the openings). In the case of the mesh shape in FIG. 1B, {(P−W) ² / P ² } × 100 is calculated from the line pitch P.

  The shape of the opening in plan view may be any shape other than the above-described square, and is not particularly limited. For example, a triangle such as a regular triangle, a square such as a square, a rectangle, a rhombus, a trapezoid, or a polygon such as a hexagon. Alternatively, it may be circular or elliptical. Further, the arrangement of the openings may be a regular arrangement or an irregular arrangement other than the square lattice arrangement. However, in the present invention, the line width W and the line pitch P in the mesh other than the square square lattice arrangement are square square mesh arrangements having the same aperture ratio K as the target mesh. The mesh shape is captured by replacing the line width W and the line pitch P in FIG. This is because the average characteristics of the entire surface are considered to be roughly similar.

  And in this invention, it is set as the shape whose line width W of a mesh is 50-100 micrometers and line pitch P is 500 micrometers-1000 micrometers as a specific shape of the planar view shape of a mesh. FIG. 2 is an explanatory diagram showing desirable combination regions (regions A) for these characteristic values of the line width W and the line pitch P. In FIG. 2, the horizontal axis represents the line width W and the vertical axis represents the line pitch P. The figure also shows a region (region B), which has been considered preferable in the past, where the line width W ≦ 40 μm and the line pitch P ≧ 200 μm. As shown in the figure, in the present invention, a practical and preferable result can be obtained for the prevention of disconnection in a portion of the region A deviating from the conventional region B.

By setting the line width W to 50 μm or more, disconnection, deformation, and inclination (falling) of the line are less likely to occur, and a beautiful line can be easily reproduced when forming the mesh. However, if the line width W exceeds 100 μm, the non-visibility of the mesh (the mesh is inconspicuous) will be reduced and practical even if the size of the display to be applied is defined as the diagonal size of the mesh part. Not.
The line pitch P is preferably increased within a range that does not affect the electromagnetic shielding performance because the aperture ratio K decreases as the line width W increases. Accordingly, the line pitch P is set to 500 μm or more. The aperture ratio K when the line pitch P is 500 μm and the line width W is 50 μm is 81%, and the aperture ratio K when the line pitch P is 500 μm and the line width W is 100 μm is 64%. The larger the line pitch P, the more advantageous in terms of the aperture ratio K. However, the line pitch P is set to 1000 μm or less. This is because when the line pitch P exceeds 1000 μm, the electromagnetic shielding performance is deteriorated.
With the above line width W and line pitch P, the aperture ratio K can be ensured to be at least 64%.

As described above, in the present invention, in the mesh shape region that has been considered to be inappropriate in the past, a range in which the performance is good is found. As a result, practical electromagnetic shielding performance and light transmittance (aperture ratio) K) can be secured and line breakage can be prevented.
Here, as for the specific sizes of the line width W and the line pitch P, square openings having a line width W = 50 μm and a line pitch P = 500 μm and an aperture ratio K = 81% are arranged in a square lattice. Mesh shape. Note that the direction in which the mesh lines extend is usually inclined from the vertical direction (or horizontal direction) at the time of application in order to prevent moire. The bias angle at that time (the angle formed between the mesh line and the outer periphery of the display electromagnetic wave shielding filter) may be appropriately set to an angle at which moire is difficult to occur in consideration of the pixel pitch of the display and the light emission characteristics.

  In the mesh layer 2, the portion of the mesh portion 2 A in which light transmittance is secured together with the electromagnetic wave shielding property by a large number of mesh-shaped openings is the mesh portion 2 </ b> A (see FIG. 1C). The mesh portion 2A may be provided in a region (surface) that requires at least light transmission as a surface. A mesh part is indispensable for the mesh layer, but there may be a non-mesh part 2B together with the part, or there may be only the mesh part 2A without the non-mesh part 2B. The non-mesh portion 2B is a portion other than the mesh portion 2A and is a region where light transmittance is not required as a surface. Usually, the non-mesh part 2B is provided in the outer peripheral part of the mesh part 2A. The non-mesh portion 2B is usually used for grounding. One example thereof is a quadrangular display electromagnetic wave shielding filter 10 illustrated in the plan view of FIG. 1C. In the same figure, portions that do not affect image display around the four sides of the mesh portion 2A are frame-shaped. The non-mesh portion 2B is provided. Such a frame-shaped non-mesh portion 2B can be used for grounding. The non-mesh part used for grounding is usually framed around all four sides. The frame-like non-mesh portion can also be used as an outer frame that enhances the appearance of the display image seen through the mesh portion by surrounding the image with a frame shape (for example, a black frame or the like). Available. In addition, it is preferable to expose at least a part of the non-mesh portion when grounding.

The size of the mesh portion 2A may be a size corresponding to the size of the display to which the electromagnetic wave shielding filter for display is applied. In particular, even in the case of a thick line width W, it is difficult to stand out to ensure the invisibility of the mesh. Therefore, the size of the mesh portion 2A is set to 800 mm or more in the diagonal dimension L [FIG. 1 (C)]. The mesh portion 2A is usually a quadrilateral according to the shape of the display, and the diagonal dimension of the quadrilateral is the diagonal dimension L. The diagonal dimension L is 800 mm or more in the case of a wide-screen television display having an aspect ratio of horizontal: vertical = 16: 9, which includes an effective screen size of 32 V (visual) type, which is larger than the 32 V type. This corresponds to a large display. Note that the aspect ratio of the target display is not limited to this, and may be a conventional aspect ratio of 4: 3 or the like.
The maximum value of the diagonal dimension L depends on the screen size of the display to be applied, and depends on the manufacturing technology of the large screen display. Incidentally, the 102 type (wide screen) is currently being marketed in the PDP. .

The non-mesh portion 2B may have an arbitrary shape according to its purpose. Therefore, the non-mesh portion may not be the entire periphery but may be two opposite sides or only one side.
Further, the non-mesh portion 2B is usually a surface portion having no opening at all, but may be a surface portion having some opening. For example, when a non-mesh portion having a shape such as a frame shape, information such as character information of a product number is expressed in the region as a set of a plurality of openings. For example, the portion is like a character printing portion in a screen plate for screen printing. However, in this case, since the portion is also small in area and the purpose is not to ensure light transmission as a surface, even if there is a portion in which a plurality of openings constituting the assembly are provided in a mesh shape , It becomes a non-mesh part.
The specific size of the non-mesh portion 2B depends on how it is used, but when the frame is in the shape of a ground or outer frame, the width of the frame is about 15 to 100 mm, especially 30 to 40 mm. Is.

[Mesh layer: its constituent layers]
If the layer structure content of the mesh layer 2 is described in more detail, it has at least a mesh-like conductor layer 21 that mainly performs an electromagnetic wave shielding function by its conductivity. When the surface of the mesh-like conductor layer 21 itself is black, it may be composed of only the mesh-like conductor layer. However, normally, if the surface blackness, durability against rust, conductivity, etc. are not sufficient from the mesh-like conductor layer alone, depending on the insufficient performance, other than this Further, the blackening layer 22, the rust prevention layer 23 and the like are also provided as the constituent layers. These additional layers such as the blackening layer and the anticorrosion layer, as long as they maintain the mesh shape that is the geometric feature of the mesh layer, these layers are used as constituent layers of the mesh layer. The invention captures it (see FIG. 3).
Therefore, in the case of the drawing in which the breakdown of the layer structure is not specified but the layer breakdown is simply indicated as the mesh layer 2 in a single layer, it is not necessary to specify the breakdown of the layer structure. It is a conceptual drawing including a mesh layer in the case of having a stratified layer.

[Mesh layer: Mesh-like conductor layer]
The mesh-like conductor layer 21 is typically formed by etching a metal foil, but other mesh layers are also significant in electromagnetic shielding performance. Therefore, in the present invention, the material and forming method of the mesh-like conductor layer are not particularly limited, and various mesh-like conductor layers in a conventionally known light-transmitting electromagnetic wave shielding filter can be appropriately employed. is there. For example, a mesh-like conductor layer is formed from the beginning on a transparent substrate using a printing method, a plating method, or the like, or initially, the entire surface is formed on a transparent substrate by a plating method. After forming the body layer, it may be a mesh-like conductor layer formed into a mesh shape by etching or the like.

  For example, when the mesh shape of the mesh-like conductor layer is formed by etching, it can be formed by patterning the metal layer laminated on the transparent base material by etching and opening the openings to form a mesh. To laminate a metal layer on a transparent substrate, the metal layer prepared as a metal foil is laminated to the transparent substrate with an adhesive, or the metal layer is deposited, sputtered, plated, etc. without using a laminating adhesive It can also be laminated on a transparent substrate using one or two or more physical or chemical forming methods. In addition, the mesh-like conductor layer by etching can also be formed into a mesh-like mesh-like conductor layer by patterning a single metal foil before lamination on a transparent substrate by etching. This single-layer mesh conductor layer is laminated on a transparent substrate with an adhesive or the like. Among these, a metal foil is laminated on a transparent substrate with an adhesive, and then meshed by etching after being easy to handle a mesh-like conductor layer with low mechanical strength and excellent in productivity. A mesh-like conductor layer that is processed and laminated on the transparent substrate via an adhesive is desirable.

  The mesh-like conductor layer is not particularly limited as long as it is a substance having sufficient conductivity to exhibit electromagnetic wave shielding performance, but usually a metal layer is preferable in terms of good conductivity, and the metal layer is as described above. It can be formed by vapor deposition, plating, metal foil lamination or the like. Examples of the metal material of the metal layer or the metal foil include gold, silver, copper, iron, nickel, and chromium. The metal of the metal layer may be an alloy, and the metal layer may be a single layer or multiple layers. For example, in the case of iron, low carbon steel such as low carbon rimmed steel and low carbon aluminum killed steel, Ni-Fe alloy, Invar alloy, and the like are preferable. On the other hand, when the metal is copper, it becomes copper or copper alloy, but as copper foil there are rolled copper foil and electrolytic copper foil, but from the point of thinness and its uniformity, adhesion with blackened layer, etc. Is preferably an electrolytic copper foil.

  In addition, the thickness of the conductor layer by a metal layer is about 1-100 micrometers, Preferably it is 5-20 micrometers. If the thickness is too thin, it will be difficult to obtain sufficient electromagnetic shielding performance due to an increase in electrical resistance, and if the thickness is too thick, it will be difficult to obtain a high-definition mesh shape. The side of the mesh disturbs the display angle of the display.

  Further, the surface of the metal layer serving as the mesh-like conductor layer is preferably a rough surface when it is necessary to improve the adhesion with an adjacent layer such as a transparent adhesive layer for adhesion and lamination with the transparent substrate. For example, in the case of copper foil, a rough surface is obtained on the surface (the surface of the blackened layer) simultaneously with the formation of the blackened layer by the blackening treatment. The degree of the rough surface is 10-point average roughness Rz [JIS-B0601 compliant (1994 version)], preferably about 0.1 to 10 μm, more preferably 1.5 μm or less, still more preferably 0.5. ˜1.5 μm. If the roughness is less than this, the effect of roughening cannot be sufficiently obtained, and if the roughness is larger than this, bubbles tend to be embraced during application of an adhesive, a resist or the like.

[Mesh layer: Blackened layer]
The blackening layer 22 can improve the bright room contrast of the display and can improve the invisibility of the mesh lines of the mesh layer. Some blackening layers have a roughened surface as described above and can improve adhesion. In terms of improving bright room contrast, the blackening layer is preferably provided on all surfaces of the mesh layer (mesh-like conductor layer itself or a mesh-like conductor layer already formed such as a rust-preventing layer) visible to the observer. Of these, if it is provided on one or more of the front, back and side surfaces, a corresponding effect can be obtained. Accordingly, the surface to be provided depends on the arrangement relationship between the electromagnetic wave shielding filter for display and the display, but only the front surface, only the back surface (see, for example, FIG. 3A), both the front and back surfaces, only the side surfaces (both sides or one side), Both side surfaces (see, for example, FIG. 3B), back surface and both side surfaces, front and back both surfaces, both side surfaces, and the like.

In any case, the blackened layer may be a layer exhibiting a dark color such as black, and may be any layer that satisfies basic physical properties such as adhesion, and a known blackened layer can be appropriately employed.
Therefore, as the blackening layer, an inorganic material such as a metal, an organic material such as a black colored resin, or the like can be used. For example, as the inorganic material, a metal compound such as a metal, an alloy, a metal oxide, or a metal sulfide is used. It is formed as a metal-based layer. As a method for forming the metal layer, various conventionally known blackening methods can be appropriately employed. Especially, the blackening process by a plating method is preferable at adhesiveness, uniformity, ease, etc. As a material for the plating method, for example, a metal such as copper, cobalt, nickel, zinc, molybdenum, tin, or chromium, a metal compound, or the like is used. These are superior to the case of cadmium or the like in terms of adhesion and blackness.

  When the mesh-like conductor layer is made of copper, such as copper foil, a preferable plating method for the blackening treatment for forming the blackened layer is a mesh-like conductor layer made of copper (because it is performed before forming the mesh shape). There is a cathodic electrodeposition plating method in which, if present, the previous conductor layer) is subjected to cathodic electrolysis in an electrolytic solution made of sulfuric acid, copper sulfate, cobalt sulfate or the like, and cationic particles are deposited. According to this method, the rough surface can be obtained simultaneously with the black color by the adhesion of the cationic particles. Copper particles and copper alloy particles can be used as the cationic particles. The copper alloy particles are preferably copper-cobalt alloy particles, and the average particle diameter is preferably 0.1 to 1 μm. A blackened layer composed of a copper-cobalt alloy particle layer is obtained by the copper-cobalt alloy particles. The cathodic electrodeposition method is also preferable in that the average particle size of the cationic particles to be adhered is adjusted to 0.1 to 1 μm. When the average particle diameter exceeds the above range, the density of the adhered particles is reduced, blackness is reduced and unevenness occurs, and particle falling off (powder falling) is likely to occur. On the other hand, even if the average particle diameter is less than the above range, the blackness is lowered. In the cathodic electrodeposition method, when the treatment is performed at a high current density, the treated surface becomes cathodic, and activated by reducing hydrogen generation, the adhesion between the copper surface and the cationic particles is remarkably improved.

  Moreover, as a blackening layer, black chrome, black nickel, a nickel alloy, etc. are preferable, and as this nickel alloy, they are a nickel-zinc alloy, a nickel-tin alloy, and a nickel-tin-copper alloy. In particular, the nickel alloy has a good degree of blackness and conductivity, can also impart a rust prevention function to the blackened layer (becomes a blackened layer and a rustproof layer), and can omit the rustproof layer. In addition, since the particles of the blackened layer are usually needle-like, the appearance is likely to change due to external force, but the blackened layer made of nickel alloy is difficult to deform and the appearance is difficult to change in the post-processing step. Benefits. In addition, the formation method of a nickel alloy as a blackening layer may be a known electrolytic or electroless plating method, and the nickel alloy may be formed after nickel plating.

[Mesh layer: Antirust layer]
As the mesh layer 2, the mesh-like conductor layer 21 made of a metal layer is rusted during manufacturing and handling, etc., and there is a concern that the electromagnetic shielding performance may be deteriorated. The exposed surface of the mesh conductor layer may be covered with the rust layer 23. Moreover, when the blackening layer mentioned above is easy to rust, it is preferable to coat | cover including a blackening layer. The coating of the antirust layer may be performed on a surface selected in consideration of the manufacturing cost from one or more necessary surfaces among the front surface, the back surface, and the side surface of the mesh-like conductor layer. Therefore, the coating of the anticorrosive layer is only the front surface, only the back surface, both front and back surfaces (see, for example, FIG. 3A), only the side surface (both sides or one side), the front surface and both side surfaces, the back surface and both side surfaces, the front and back both surfaces and both side surfaces. Etc.

  The rust preventive layer is not particularly limited as long as it does not rust more easily than the mesh-like conductor layer coated with the rust preventive layer, such as an inorganic material such as metal, an organic material such as resin, or a combination thereof. In some cases, the blackened layer is also covered with a rust-preventing layer, so that the particles of the blackened layer can be prevented from falling off and deformed, and the blackness of the blackened layer can be increased. In this respect, when the mesh-like conductor layer is formed of a metal foil, when the blackened layer is provided on the metal foil on the transparent substrate by the blackening treatment, the blackened layer is prevented from falling off or being altered. In terms of meaning, it is preferably provided before lamination of the transparent substrate and the metal foil.

  As the rust prevention layer 23, a conventionally known layer may be appropriately employed, and for example, a metal or alloy such as chromium, zinc, nickel, tin, copper, or a metal compound metal oxide layer may be used. These can be formed by a known plating method or the like. Here, if it shows an example of a rust prevention layer preferable at points, such as a rust prevention effect and adhesiveness, the chromium compound layer obtained by carrying out a chromate process after galvanization will be mentioned. Moreover, the rust prevention layer by this chromium compound layer is the blackening layer which consists of the copper-cobalt alloy particle layer mentioned later, and the transparent adhesive layer 5 at the time of carrying out the adhesion lamination of the transparent base material 1 and the mesh layer 2 (especially). Excellent adhesion to a two-component curable urethane resin adhesive).

In the case of chromium, chromate (chromate) treatment or the like may be used. The chromate treatment is carried out by bringing the chromate treatment solution into contact with the treated surface. This contact is not limited to coating methods such as roll coating, curtain coating, squeeze coating, pouring (single-sided contact), and electrostatic fogging. According to the chemical method, the dipping method, etc., double-sided contact is also possible. Moreover, what is necessary is just to dry, without washing with water after a contact. In addition, an aqueous solution containing chromic acid is usually used for the chromate treatment liquid. Specifically, “Alsurf (registered trademark) 1000” (manufactured by Nippon Paint Co., Ltd.), “PM-284” (Nippon Parkerizing Co., Ltd.) A processing solution such as a company) can be used.
In the chromate treatment, galvanization before the treatment is preferable in terms of adhesion and rust prevention effect. In addition, the rust preventive layer may contain a silicon compound such as a silane coupling agent in order to improve acid resistance during etching or acid cleaning.
In addition, the thickness of a rust prevention layer is about 0.001-10 micrometers normally, Preferably it is 0.01-1 micrometer.

[Colored filter layer]
The colored filter layer 3 is an achromatic or chromatic transparent layer that absorbs visible light. Such a colored filter layer itself is an electromagnetic wave shield as a neon light absorbing filter, a color adjustment filter, an external light antireflection filter, or the like. Already known in filters. In particular, in the present invention, such a colored filter layer is provided as the colored filter layer 3 that covers the viewer side of the display of the mesh layer on the transparent substrate, thereby making the mesh line more inconspicuous and further non- Visibility can be improved. It should be noted that the provision of the mesh layer so as to cover the viewer side means that the mesh layer passes through the colored filter layer when viewed from the viewer side of the display image with the display electromagnetic wave shielding filter installed on the front of the display. It means that it can be seen only. When the electromagnetic wave shielding filter for display 10 is installed so that the mesh layer 2 side of the electromagnetic wave shielding filter for display 10 faces the viewer side, a colored filter layer is formed on the front side of the mesh layer as shown in FIG. Further, when the display electromagnetic wave shielding filter 10 is installed so that the transparent substrate 1 side faces the observer side, although not shown, a colored filter layer is provided on the back side (the side opposite to the mesh layer) of the transparent substrate 1. Form. Of course, even if such a colored filter layer 3 is not provided, the colored filter layer 3 may be omitted if the mesh line is already inconspicuous and further improvement in invisibility is unnecessary. However, there is a colored filter layer having the same layered positional relationship as that of the colored filter layer of the present invention for the purpose other than the improvement of the invisibility, for example, neon light absorption, color adjustment, anti-reflection of external light, and the like. May be. Moreover, it is good also as the colored filter layer 3 which also serves these other purposes.

By the way, in the present invention, the colored filter layer 3 provided so as to cover the front side of the mesh layer as shown in FIG. 4 is roughly divided into two types according to the layer positional relationship with the mesh layer. That is, as in the colored filter layer 3 illustrated in the cross-sectional view of FIG. 4A, a configuration in which the mesh layer 2 is directly covered so as to fill the surface unevenness by the mesh layer 2, and FIG. As in the colored filter layer 3 illustrated in the cross-sectional view, the surface unevenness due to the mesh layer 2 is first flattened with a colorless and transparent flattening resin layer 4 that fills at least the concave portion in the opening, and then the flattening resin layer 4 In this form, the mesh layer 2 is indirectly covered on the top.
Note that the colored filter layer 3 in the form of FIG. 4A also has a function of flattening the surface unevenness due to the mesh layer 2 and is a layer that also serves as the flattening resin layer 4 described in FIG. Become.
Further, in FIG. 4B, the flattening by the flattening resin layer 4 is more preferably complete flatness, but it may be closer to flatness if it is not perfect flatness. Is not necessary. Therefore, if the mesh layer 2 is indirectly covered when the latter is not directly above the line portion, the mesh layer and the colored filter layer are in direct contact with each other directly above the line portion.
In the case of FIG. 4B, the planarizing resin layer may function as an adhesive layer. Of course, an adhesive layer (not shown) may be provided between the flattening resin layer.

  As described above, in the case where the colored filter layer 3 according to the present invention is formed on the front side of the mesh layer, the form (FIG. 4 (A)) that also serves as the planarizing resin layer or the form that does not serve as the same (FIG. 4 (B)). However, either may be used. In the shared mode, the layer configuration is reduced correspondingly, and the manufacturing process can be simplified. In addition, in the form that is not shared as shown in FIG. 4B, there is an advantage that the thickness uniformity of the colored filter layer (surface uniformity of the filter performance) can be easily obtained, and the planarized resin layer surface that completely covers the mesh layer. In the case where it is provided above, there is also an advantage that it is possible to avoid the concern that the dye added to the colored filter layer deteriorates with time due to the metal of the mesh layer.

  The reason why the non-visibility of the line is improved by the colored filter layer 3 will be described. The display electromagnetic wave shielding filter is used from the observer side to the display electromagnetic wave shield by using the colored filter layer side as the observer side. Even if the external light incident on the shield filter is reflected by the mesh layer, it passes through the colored filter layer at least twice in the forward path and the return path. Therefore, compared with the case where the image light of the display that passes through the electromagnetic wave shielding filter for display from the transparent substrate side to the mesh layer side passes through the colored filter layer only once, the external light reflected by the mesh layer is the colored filter layer. The light absorption of is large. As a result, the non-visibility of the mesh of the mesh layer is improved while the adverse effect on the brightness of the display is minimized.

  As the colored filter layer 3 as described above, a known colored filter material made of an inorganic material such as colored glass or a vapor-deposited thin film or an organic material such as a colored resin may be appropriately employed. For example, in the case of a colored resin, it is formed as a layer containing a dye in a transparent resin binder. In addition, the colored filter layer formed from such a dye and a resin binder has an advantage that a low-cost forming method such as a coating method or a printing method can be used.

The resin of the resin binder is not particularly limited as long as it is a transparent resin, and a known resin may be appropriately employed. For example, a thermoplastic resin, a thermosetting resin, an ionizing radiation curable resin, or the like. For example, thermoplastic resins are acrylic resins, polyester resins, thermoplastic urethane resins, vinyl acetate resins, etc., and thermosetting resins are urethane resins, epoxy resins, curable acrylic resins, etc. Examples of the radiation curable resin include acrylate resins that are cured by ultraviolet rays or electron beams.
In addition, in the case where the planarizing resin layer is also used, ionizing radiation can be formed in a solvent-free or nearly solvent-free state in terms of the function as the planarizing resin layer, that is, in terms of easily filling the unevenness by the mesh layer. A curable resin is a more preferred resin.

  In order to form a colored filter layer with a resin binder containing a dye, a composition containing the resin and the dye as described above, usually a solvent, and various other additives as required, It can be formed by a known layer forming method such as a coating method or a printing method by using it as an ink. Specifically, the display observer side surface of the electromagnetic wave shielding filter for display with the mesh layer laminated, for example, the surface on the mesh layer side of the transparent base material, or even the planarizing resin layer in the form of FIG. When formed on the surface of the mesh layer, a coating method such as roll coating, comma coating or gravure coating, or a printing method such as screen printing or gravure printing is appropriately employed for the surface of the flattening resin layer. Can be formed. In the printing method, partial formation in an arbitrary shape is easy, but even in the coating method, partial formation can be performed by intermittent coating.

  In addition, as a pigment to be included in the resin binder, if only non-visibility is aimed, an achromatic ND (Neutral Density) whose wavelength dependency of light absorption in the visible light region is flat (or substantially flat). Filters) filter is preferred. However, the colored filter layer 3 may also have another optical filter function. In this case, for example, in the neon light absorption, color adjustment, etc., the color may be consciously chromatic.

  In addition, what is necessary is just to use the pigment | dye according to the said filter objective as a pigment | dye contained in a resin binder, For example, if an achromatic ND filter may be used, a well-known organic pigment | dye, a pigment, etc. may be used suitably. Moreover, you may use together 2 or more types of pigment | dyes other than single 1 type use. For example, if the color is undesirably exhibited by addition of a dye, another dye that cancels the color and approaches an achromatic color may be used in combination.

  The colored filter layer is composed of a resin as described above, usually a solvent, and a composition containing various other additives, pigments, and the like as a coating liquid or ink. It can be formed by a known layer forming method. Specifically, the coating method such as roll coating, comma coating, gravure coating, or screen printing on the surface on the mesh layer side of the transparent substrate on which the mesh layer is laminated, or the surface on the transparent substrate side, A printing method such as gravure printing may be employed as appropriate. In the printing method, partial formation in an arbitrary shape is easy, but even in the coating method, partial formation can be performed by intermittent coating.

[Flatening resin layer]
The flattening resin layer 4 has already been partially described in the above color filter layer, but as shown in the cross-sectional view of FIG. In the case where the colored filter layer 3 is provided, it is easy to obtain a uniform thickness of the colored filter layer by flattening the surface on which the colored filter layer is formed as the base layer of the colored filter layer 3, or the colored filter layer 3 is not provided. Is a layer that prevents entrapment of air bubbles and protects the mesh layer from external force when the mesh layer is laminated with an adherend and an adhesive. In terms of protection, the planarizing resin layer is also a surface protective layer.
Such a flattened resin layer 4 can be formed by applying a liquid composition containing a resin to the uneven surface generated by the mesh layer 2 laminated on the transparent substrate 1 by coating or the like. The liquid composition is not particularly limited as long as it contains a transparent resin, and a known resin may be appropriately employed. For example, a thermoplastic resin, a thermosetting resin, an ionizing radiation curable resin, etc. listed in the colored filter layer.

  In addition, you may utilize a shaping sheet | seat in order to make the surface of the planarization resin layer into a desired flat surface. The method of using the shaped sheet is, for example, from the top of the mesh layer laminated on the transparent substrate, while applying the coating liquid for forming the planarizing resin layer and the coating film is liquid, Cover the surface with a shaping sheet, shape the flat surface of the shaping sheet on the surface, and solidify the coating film. By peeling the shaped sheet, the surface of the flattening resin layer is made a desired flat surface. Alternatively, if a state in which the coating film is plastically deformed by heating appears even after the coating is solidified, the shaped sheet may be peeled off after being formed by heating and pressurizing and shaping.

The shaping sheet is not particularly limited as long as it has releasability from the coating film of the flattening resin layer and a flat surface, and an appropriate material may be selected and used. Examples of such materials include polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyamide resins such as nylon 6, and polyolefin resins such as polypropylene and polymethylpentene. Is mentioned. As a specific example, a biaxially stretched polyethylene terephthalate sheet is suitable.
Note that the shaping surface of the shaping sheet (that is, the surface of the flattening resin layer as a result) is a flat surface, but it is a mirror surface or a fine uneven surface for the purpose of improving the adhesion of the shaping surface. It is also good. In addition, when the resin sheet alone is used as the shaping sheet, if the mold release property of the shaping surface is insufficient, a release layer made of a release material such as silicone may be formed on the shaping surface.

  In addition, you may utilize the said shaping sheet similarly also about the case where it forms in the form which combines a colored filter layer with the planarization resin layer.

  In addition, the flattening resin layer or the colored filter layer that also serves as the flattening resin layer can be flattened if it is provided at least in the opening of the mesh layer for the purpose of flattening. A transparent layer that is laminated by a transparent adhesive layer on the entire surface of the transparent substrate and prevents the light transmission from being deteriorated because the surface of the transparent adhesive layer exposed at the opening is a rough surface. It can also function as a fluorinated resin layer. Therefore, a flattening resin layer or a colored filter layer that also serves as a flattening resin layer may be used.

[Other layers]
The electromagnetic wave shielding filter for display according to the present invention may have a configuration in which layers other than the above-described layers are appropriately laminated as necessary. For example, a transparent adhesive layer, a planarizing resin layer (partly described above), an optical filter layer other than the colored filter layer, a surface protective layer, an adhesive layer, an adherend, and the like. These may be known ones in conventional electromagnetic wave shielding filters.

(Other layers: transparent adhesive layer)
The transparent adhesive layer is interposed between the transparent substrate 1 and the mesh layer 2 as shown in the cross-sectional view of FIG. 5A, and is used to bond and laminate these layers. . The figure shows a case where the mesh layer 2 is formed from a metal foil such as a copper foil. As a result, the transparent adhesive layer 5 exists on the entire surface of the transparent substrate 1 including the opening of the mesh layer 2. It is a form. The transparent adhesive used for the transparent adhesive layer is not particularly limited, and a known adhesive may be appropriately employed. For example, urethane adhesives, acrylic adhesives, epoxy adhesives, rubber adhesives, and the like can be given.

[Other layers: adherend, other optical filter layers, surface protective layers, etc.]
The adherend is, for example, another optical filter layer (film, sheet, plate) other than the colored filter layer 3, a surface protective layer (film, sheet, plate), and the like, and is a cross-sectional view of FIG. An example of the adherend 6 shown in FIG. 5 shows an example in which the colored filter layer 3 is combined with the adhesive layer or not, and is incorporated on the surface side of the display electromagnetic shielding filter 10. Here, the optical filter function of the optical filter layer includes near infrared absorption, antireflection (including antiglare), color tone adjustment (neon light absorption, improved color reproducibility), ultraviolet absorption, and the like. The function of the surface protective layer is antifouling, hard coat and the like. These may be appropriately selected from conventionally known ones. Other optical filter layers and surface protective layers may be formed not on the adherend but on appropriate layers or on the outermost surface by coating or the like (however, the surface protective layer is formed on the outermost surface).

On the contrary, the adherend 6 may be laminated on the back side of the electromagnetic wave shielding filter for display as illustrated in the cross-sectional view of FIG. In the figure, the back surface of the adherend 6 is the display side exposed surface. Further, in the same figure, there is no particular indication between the transparent substrate 1 and the adherend 6, but when there is no adhesion between them, a transparent adhesive layer is appropriately laminated therebetween. In addition, what is necessary is just to employ | adopt well-known adhesives, such as a non-adhesive adhesive agent or an adhesive (adhesive layer), as a contact bonding layer also including the case where the said planarization resin layer is combined with an adhesive layer. Further, the adherend may be laminated on the front and back surfaces of the electromagnetic wave shielding filter for display. In that case, the type (function) of the adherend can be properly used on the front and back sides.
In addition, when making the surface side of the electromagnetic wave shielding filter for displays into the observer side, as a to-be-adhered body laminated | stacked on the back side of this filter, the front plate etc. of display itself are mentioned.

[Others]
In addition, in the resin constituting the transparent base material, the flattening resin layer, the transparent adhesive layer, the surface protective layer, the adhesive layer, the pressure-sensitive adhesive layer, the adherend, etc., an external light antireflection pigment, a neon light absorber In the electromagnetic wave shielding filter such as a color adjusting dye, a known dye may be appropriately added.

  Further, FIG. 3 for explaining the details of the mesh layer, FIG. 4 and FIG. 5 for explaining the other layers, etc. exemplify each example, but it goes without saying that these may be combined as appropriate. is there. The present invention is not limited to these drawings or the following examples.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[Example 1]
A desired electromagnetic wave shielding filter 10 for a display having a mesh shape as shown in FIGS. 1B and 1C and a mesh layer structure as shown in FIG. 3A was produced as follows. First, as a metal foil used as the mesh-like conductor layer 21, a continuous strip-shaped electrolytic copper foil having a thickness of 10 μm in which a blackened layer 22 made of copper-cobalt alloy particles was formed on one surface was prepared. Further, as the transparent substrate 1, a non-colored transparent biaxially stretched polyethylene terephthalate film having a thickness of 100 μm and a continuous web was prepared.

  And after carrying out zinc plating with respect to both surfaces of the said copper foil, the well-known chromate process was performed by the dipping method, and the antirust layer 23 was formed in both front and back surfaces. Next, the copper foil was dry laminated with the transparent two-component curable urethane resin adhesive on the transparent base on the blackened layer surface side, and then cured at 50 ° C. for 3 days to obtain a copper foil (rust prevention layer). A copper-laminated laminated sheet was obtained as a continuous web having a transparent adhesive layer 5 having a thickness of 7 μm between the transparent substrate and the transparent substrate (see FIG. 5A for the transparent adhesive layer).

Next, the copper foil (the entire conductor layer, blackening layer, and rust prevention layer) is etched on the copper-laminated laminate sheet by etching using a photolithography method, and the rust prevention layer 23 and the mesh conductor layer. A mesh laminated sheet in which the mesh layer 2 composed of 21 and the blackened layer 22 was formed on the transparent substrate 1 was obtained.
Specifically, the etching was performed from masking to etching on the continuous belt-shaped copper-clad laminate sheet using a production line for a color TV shadow mask. That is, after applying an etching resist to the entire surface of the conductor layer of the copper-clad laminate sheet, a desired mesh pattern is closely exposed, developed, hardened, baked, and then blackened with a ferric chloride solution, an anticorrosive layer The copper foil was etched to form a mesh-shaped opening, and then washed with water, stripped of resist, washed, and dried sequentially.

The mesh shape of the mesh layer is a square lattice shape in which the openings A _O are square and regularly arranged vertically and horizontally as shown in FIG. 1B, and the mesh line width W is 50 μm and the line pitch P is 500 μm ( The aperture ratio K is 81%), which is a bias angle of 49 degrees defined as a minor angle with respect to the long side [see FIG. 1C] of the rectangular area of the mesh portion 2A. The size of the mesh portion 2A of the mesh layer is a mesh portion shape corresponding to a wide screen having a diagonal dimension L of 820 mm (equivalent to 32V type) and an aspect ratio of horizontal: vertical = 16: 9. Further, the mesh of the mesh layer is such that when a continuous belt-like web is cut into a sheet having a desired size, a non-mesh portion 2B having a frame shape with a width of 40 mm having no openings on the outer periphery of the four sides is left. Etched into.

  Next, in order to unwind the mesh laminated sheet once wound up and form the flattened resin layer 4 on the surface of the mesh layer 2, the non-mesh portion 2B is partially coated with the acrylic resin coating liquid. It was coated on the mesh layer by intermittent coating by an intermittent die coating method so as to be exposed. Apply the coating from the mesh part to the non-mesh part of the outer periphery by 2.5mm until it enters the non-mesh part, and leave the outer non-mesh part as an exposed part without coating. did. Further, the planarizing resin layer 4 was formed as a continuous layer on the mesh layer including the portion directly above the line portion together with the opening in the mesh portion (thickness 8 μm immediately above the line portion).

  And after the said application | coating, as a shaping sheet | seat which shapes a flat surface with respect to the coating film after drying a solvent, the continuous-belt-shaped commercially available biaxially-stretched polyethylene terephthalate film with a thickness of 50 micrometers is the unadhesive process. After laminating to the coating film on the surface, it was peeled off to form a transparent flattened resin layer 4 having a flat surface and covering the mesh part (and part of the non-mesh part) of the mesh layer.

Then, a transparent black paint with the addition of black organic pigments in an acrylic resin binder, the exposed portion of the non-mesh portion on the upper Symbol portions formed planarizing resin layer 4 is intermittently applied as leave, thickness After forming a colored filter layer 3 having a visible light transmittance of 70% at 10 μm (single colored filter layer alone), it is cut into a rectangular sheet as shown in FIG. An electromagnetic wave shielding filter 10 was produced (see FIG. 4B, but the transparent adhesive layer 5 is not shown).

[Example 2]
An electromagnetic wave shielding filter for display was produced in the same manner as in Example 1, except that the line width W was changed to 100 μm and the line pitch P was changed to 1000 μm (the aperture ratio K was 81%).

Example 3
In Example 1, an electromagnetic wave shielding filter for display was produced in the same manner as in Example 1 except that the formation of the colored filter layer was omitted.

[Comparative Example 1]
In Example 1, except that the line width W was changed to 40 μm, the line pitch P was changed to 400 μm (the aperture ratio K was the same at 81%), and the formation of the colored filter layer was omitted, the same as in Example 1, An electromagnetic shielding filter for display was created.

[Comparative Example 2]
In Example 1, the line width W was changed to 10 μm, the line pitch P was changed to 200 μm (the aperture ratio K was 90.3%), and the formation of the colored filter layer was omitted, and the same as in Example 1. An electromagnetic shielding filter for display was created.

[Comparative Example 3]
An electromagnetic wave shielding filter for display was produced in the same manner as in Example 1, except that the line width W was changed to 200 μm and the line pitch P was changed to 1000 μm (the aperture ratio K was 64%).

[Performance evaluation]
About the electromagnetic wave shielding filter for each display of an Example and a comparative example, the non-visibility of the mesh line and the generation | occurrence | production condition of the disconnection of this line at the time of manufacture were evaluated. The results are shown in Table 1.

(1) Line invisibility: An electromagnetic shielding filter for display is placed on the front surface of the PDP with its mesh layer side facing the viewer, and it is visually observed whether the line is conspicuous from a position with a clear viewing distance of 100 cm. And evaluated. The case where the line was not conspicuous was evaluated as good (◯), the case where it was slightly conspicuous but within the good level was almost good (Δ), and the case where the line was conspicuous was evaluated as bad (×).
(2) Line break: the electromagnetic wave shielding filter of the examples and comparative examples was processed under the same conditions was observed under magnification the line portion A _L of the mesh layer under a microscope. In the mesh portion, breaking the line section A _L, or inclined (line section A _L side rises vertically on a transparent substrate by etching time is inclined to have the state. Line portion side and a transparent substrate surface The case where none of the angle formed by the angle of less than 90 ° or more than 90 ° was recognized was evaluated as good (◯). The line portion A _L disconnected, or that any observed slope was evaluated impossible (×).

  As shown in Table 1, the invisibility was almost good only in Example 3 where there was no colored filter layer, but in Examples 1 and 2 where the colored filter layer was present, the line was not noticeable by the colored filter layer. In comparison with Example 3, the line width W was 100 μm, including Example 2, which was thick, and was favorable. In all of Examples 1 to 3, disconnection was also good. However, Comparative Example 1 and Comparative Example 2 had good non-visibility, but disconnection was impossible. Further, in Comparative Example 3 in which the line width was increased to 200 μm, disconnection was good, but non-visibility was not possible.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which illustrates conceptually the electromagnetic wave shielding filter for displays by this form with the form, (A) is sectional drawing of a layer structure, (B) is a partial enlarged plan view of a mesh shape, (C) is a mesh. The whole top view which shows a part and its diagonal dimension. Explanatory drawing which shows the desirable combination range of line width W and line pitch P. FIG. Sectional drawing which illustrates two examples as a detailed structure of the layer structure of a mesh layer. Sectional drawing which illustrates two examples as a structural example which has a colored filter layer. Sectional drawing which illustrates three examples as additional layer structures other than the transparent base material except a colored filter layer, and a mesh layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent base material 2 Mesh layer 2A Mesh part 2B Non-mesh part 21 Mesh-like conductor layer 22 Blackening layer 23 Antirust layer 3 Colored filter layer 4 Flattening resin layer 5 Transparent adhesive layer 6 Adhering body 10 Display electromagnetic wave Shield filter A _L line (non-opening)
A _O Opening L Diagonal dimension P Line pitch W Line width

Claims (2)

In an electromagnetic wave shielding filter for a display in which a mesh layer having a mesh portion having a mesh shape in a plan view is formed on a transparent substrate,
An electromagnetic wave shielding filter for a display, wherein the mesh shape of the mesh layer is a line width W of 50 to 100 µm, a line pitch P of 500 µm to 1000 µm, and a mesh portion having a diagonal dimension L of 800 mm or more. The electromagnetic wave shielding filter for a display according to claim 1, further comprising a colored filter layer so as to cover an observer side of the display of the mesh layer on the transparent substrate.

Images