JP2007243069A - Manufacturing method of composite filter and composite filter obtained by the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a composite filter capable of exposing and grounding an electromagnetic wave shield sheet without the need for exfoliating and eliminating step of another optical filter layer from on the electromagnetic wave shield sheet. <P>SOLUTION: The manufacturing method of the composite filter comprising (A) a continuous belt-like electromagnetic wave shield sheet 1 with a width W formed by laminating a mesh region and a grounding region 40 with a thickness of 5μm or below capable of entirely covering an image display region of a display to be applied on one side of a transparent substrate 11, and (B) a continuous belt-like adhesive optical filter 21 with a width X narrower than the width W one side of which an adhesive layer is laminated and at least part of a grounding region can be exposed, includes: directing the adhesive layer side of the continuous belt-like adhesive optical filter 21 to the conductor layer side of the electromagnetic wave shield sheet; continuously supplying the continuous belt-like adhesive optical filter 21 in a way of opposing just above the image display region part of the display in the electromagnetic wave shield sheet; adhering and laminating them; and exposing side end edges of the electromagnetic wave shield sheet as a grounding region. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a composite filter having an electromagnetic wave shielding function for shielding electromagnetic waves generated from a display such as a CRT or PDP, and an optical filter function, and more specifically, an optical filter layer from an electromagnetic wave shielding sheet. The present invention relates to a method for manufacturing a composite filter that can be grounded without peeling and / or removal.

  In recent years, with the advancement of functions and increased use of electric and electronic equipment, electromagnetic noise interference (EMI) has increased, and displays such as cathode ray tubes (CRTs) and plasma display panels (hereinafter referred to as PDPs). But electromagnetic waves are generated. A PDP is a combination of a glass having a data electrode, a fluorescent layer, and a glass having a transparent electrode, and generates a large amount of electromagnetic waves, near infrared rays, and heat when activated. Usually, in order to shield electromagnetic waves, a front plate including an electromagnetic wave shielding sheet is provided on the front surface of the PDP. The shielding property of electromagnetic waves generated from the front surface of the display requires a function of 30 dB or more at 30 MHz to 1 GHz. In addition, near infrared rays having a wavelength of 800 to 1,100 nm generated from the front of the display also cause other devices such as VTRs to malfunction, and need to be shielded.

  The electromagnetic wave shielding sheet used for such applications requires light transmittance as well as electromagnetic wave shielding performance. Therefore, as an electromagnetic shielding sheet, a transparent conductive ITO (indium tin oxide) film provided on the entire surface of a transparent substrate, or a metal such as a copper foil bonded to a transparent substrate made of a resin film with an adhesive Known is a foil etched into a mesh shape.

  In addition to the electromagnetic wave shielding function, the front plate placed on the front of the display blocks unnecessary light emitted from the display (for example, light with a wavelength of about 590 nm due to neon light emission in PDP), and adjusts the hue of the image to reproduce the color. There are cases where a function to improve the performance, a function to suppress unnecessary reflection of external light, a function to suppress unnecessary infrared radiation from the display and to prevent malfunction of an infrared using device may be required. Therefore, as the actual front plate, an electromagnetic wave shielding sheet and an optical filter having other filter functions, for example, a color filter, antireflection filter, near infrared absorption filter, etc., laminated and integrated into a composite filter are used. (For example, Patent Document 1).

When laminating the optical filter layer on the metal mesh surface, the surface of the metal mesh area is flattened by filling the mesh openings with a transparent resin called a flattening resin in advance. In general, the optical filter layer or the like is laminated on the layer via an adhesive layer. This is because the metal mesh layer has a concave and concave surface, and if an optical filter layer is directly laminated with an adhesive, bubbles remain in the metal mesh opening, and the light scattering of the bubbles causes compounding. This is because the problem arises that the haze value of the filter increases.
In the composite filter as described above, the metal mesh of the electromagnetic wave shielding sheet needs to be grounded. For this purpose, it is common to have a frame-like metal layer that is provided so as to surround the periphery of the metal mesh and that does not form an opening, and is grounded from this frame-like metal layer (Patent Literature). 1).
The conventional composite filter as described above is formed by laminating an electromagnetic wave shielding sheet and an optical filter, each cut to the size of one display, over the entire surface including the grounding portion.
In addition, the grounding process as described above is inevitably performed at a stage close to the final process in which each completed composite filter and display body are combined.
For this reason, when grounding, it is necessary to first peel off the laminated optical filter layer from the frame part of the part to be grounded to expose the metal of the frame part for the composite filter once laminated in all layers. is there. In this case, when the optical filter is peeled off, the metal layer on the frame portion of the thin film may be damaged and peeled off together. In addition, extra materials and processes for flattening the mesh-like region are required.
Under such circumstances, it is desired to omit the work for grounding and the flattening process.

On the other hand, as an exposure method at the time of grounding, for example, when the composite filter is cut into a size for one display, a cut that reaches the thickness of the entire optical filter layer to be peeled off separately from the cut portion (half cut) ) Is laminated on the electromagnetic wave shielding sheet in a state where it is placed 10 mm away from the end of the composite filter, for example, and then the optical filter layer and adhesive layer on the edge are peeled and removed at the cuts. Has been proposed (for example, Patent Document 2).
However, since the exposure work of the grounding portion described in these patent documents needs to be performed once for each display, mass production processing cannot be performed collectively, production efficiency is poor, and complicated. In addition, there is a problem that the processing requires a skill, and if it fails, the entire composite filter is wasted.
Also, a glass substrate is prepared, and an optical filter is laminated on the front surface side (observer side). On the other hand, an electromagnetic wave shielding sheet is exposed on the back surface side (display side) of the glass plate, and the metal mesh side is exposed on the outermost surface. A method of stacking in such a direction has also been proposed (for example, Patent Document 3).
In this case, since the frame portion for grounding is exposed on the outermost surface, it is not necessary to peel and remove the optical filter from the frame portion for grounding.
However, instead, the frame portion is sandwiched between the back surface of the composite filter and the space between the composite filter and the display, which causes another problem that the grounding work becomes difficult.

JP 2003-86991 A JP 2003-66854 A JP 2001-210988 A

  The present invention has been made in view of the above-described problems, and is performed for grounding a composite filter, without removing and removing other optical filter layers from the electromagnetic wave shielding sheet. The main object of the present invention is to provide a method of manufacturing a composite filter that can be exposed and grounded and that can be easily grounded.

In order to solve the above-mentioned problems, the present inventors have a composite filter in which an electromagnetic shielding sheet having a frame-shaped grounding portion and an optical filter are laminated, and a step of removing another optical filter layer from the electromagnetic shielding sheet. First, the present invention was completed by intensively studying a method for manufacturing a composite filter capable of exposing and grounding an electromagnetic wave shielding sheet and a composite filter.
That is, the present invention
A method for producing a composite filter for a display comprising a laminate of an electromagnetic wave shielding sheet and an optical filter,
(A) A mesh-like region having a thickness of 5 μm or less capable of covering the entire image display region of the applied display on one surface of the transparent substrate and a part of at least one side edge around the mesh-like region A continuous band-shaped electromagnetic wave shielding sheet having a width dimension W formed by laminating at least a conductor layer having a grounding area;
(B) An adhesive layer is laminated on one surface to cover all portions of the electromagnetic wave shielding sheet facing the image display region of the display and to expose at least a part of the grounding region. and a continuous strip-like adhesive optical filter having a narrow width X than the width W,
The adhesive layer side of the adhesive optical filter said continuous band-like, towards the conductive layer side of the electromagnetic shielding sheet, and the continuous strip-like adhesive optical filter facing the image display area of the display in the electromagnetic shielding sheet was continuously fed to cover the portion directly above the, the electromagnetic shielding sheet to bond the continuous strip-like adhesive optical filter, and laminating at least one side edge of the electromagnetic shielding sheet as a ground area, is exposed And (2) a composite filter for display obtained by the production method described in (1) above.

In the present invention, a continuous band-shaped electromagnetic wave shielding sheet having a width dimension W formed by laminating at least a conductor layer having a grounding region on a part of an edge on one side around a mesh-shaped region, and an adhesive layer on one surface A continuous band-like adhesive optical filter having a width dimension X narrower than the width dimension W, in which at least a part of the grounding region can be exposed, and the electromagnetic wave shielding. Adhering and laminating the above continuous belt-like adhesive optical filter on a sheet, and using both side edges of the electromagnetic wave shielding sheet as a grounding area, the exposed composite filter manufacturing method is used. The working area is reliably formed. For this reason, the composite filter obtained by the manufacturing method of the present invention exposes the electromagnetic wave shielding sheet without having a step of removing the other optical filter layer from the electromagnetic wave shielding sheet, which is performed for grounding the composite filter. And can be grounded.
Moreover, in the method for manufacturing a composite filter for display according to the present invention, as the electromagnetic wave shielding sheet, the line portion height of the mesh region is 5 μm or less, and the opening width of the opening portion of the mesh region is 150 μm or more. A continuous belt-like adhesive optical filter using an electromagnetic wave shielding sheet without a flattening layer coating at the opening in the mesh-like region, and having an adhesive layer having high fluidity during bonding and lamination as the continuous belt-like adhesive optical filter Can prevent bubbles from remaining in the openings of the mesh when laminating and bonding the electromagnetic wave shielding sheet and the optical filter while omitting the step of flattening the mesh surface. To avoid the inconvenience of increasing the haze value of the product, and to obtain a highly transparent composite filter with high production efficiency it can.
Furthermore, since the mesh area is 5 μm or less in thickness, no extra adhesive is required for the flattening process, and the adhesive layer flows out of the ground area, deviates, or adheres to the optical filter. There is an effect that there is no positional deviation from the agent layer.
That is, the method for manufacturing a composite filter according to the present invention does not have a step of removing the other optical filter layer from the electromagnetic wave shielding sheet for grounding the composite filter, and exposes and grounds the electromagnetic wave shielding sheet. It is possible to obtain a composite filter having high transparency with high production efficiency while omitting the step of flattening the possible composite filter on the mesh surface.

The production method of the present invention is a method for producing a composite filter for a display comprising a laminate of an electromagnetic wave shielding sheet and an optical filter,
(A) A mesh-like region having a thickness of 5 μm or less capable of covering the entire image display region of the applied display on one surface of the transparent substrate and a part of at least one side edge around the mesh-like region A continuous band-shaped electromagnetic wave shielding sheet having a width dimension W formed by laminating at least a conductor layer having a grounding area;
(B) An adhesive layer is laminated on one surface to cover all portions of the electromagnetic wave shielding sheet facing the image display region of the display and to expose at least a part of the grounding region. A continuous strip-like adhesive optical filter having a width dimension X narrower than the width dimension W;
Directly above the part where the adhesive layer side of the continuous band-like adhesive optical filter faces the conductor layer side of the electromagnetic wave shielding sheet and the continuous band-like adhesive optical filter faces the image display area of the display in the electromagnetic wave shielding sheet The continuous band-like adhesive optical filter is adhered to and laminated on the electromagnetic wave shielding sheet, and at least one side edge of the electromagnetic wave shielding sheet is exposed as a grounding region. This is a method for manufacturing a composite filter for display.
Moreover, the composite filter for display of this invention is a composite filter for display obtained by the said manufacturing method.
Hereinafter, the present invention will be described in detail.

<(A) Electromagnetic wave shielding sheet>
The electromagnetic wave shielding sheet of (A) in the present invention is a mesh-like region capable of covering the entire image display region of the display to be applied on one surface of the transparent substrate, and at least one side edge around the mesh-like region. This is an electromagnetic wave shielding sheet having a continuous belt-like shape with a width dimension W formed by laminating at least a conductor layer having a grounding region at a part of the edge (hereinafter also simply referred to as an electromagnetic wave shielding sheet). The width dimension W is a dimension in a direction orthogonal to the continuous direction (flow direction or longitudinal direction) of the electromagnetic wave shielding sheet supplied in a continuous band shape when the composite filter is continuously produced, as shown in FIG. It is exemplified as one unit of electromagnetic wave shielding sheet (a part corresponding to one display device). In FIG. 1A, the left-right direction is the longitudinal direction, and one unit of the electromagnetic wave shielding sheets illustrated in this direction is connected continuously and periodically (not shown). The width dimension W corresponds to the dimension in the vertical (y) direction in FIG. Usually, the width direction is generally applied to the vertical direction of the display device, but the longitudinal (x) direction may be the vertical direction of the display device.
In general, the width in the (y) direction perpendicular to the longitudinal direction (x) to be continuously supplied is W, and the width W may include a side edge used as a grounding region.

An example of the electromagnetic wave shielding sheet used in the present invention is shown in FIG. FIG. 1A is a plan view of an example of an electromagnetic wave shielding sheet (one unit) used in the present invention, and FIG. 1B is a cross-sectional view of an example of an electromagnetic wave shielding sheet used in the present invention. As shown in FIG. 1A, the electromagnetic wave shielding sheet 1 of the present invention includes a mesh region 101 that can cover all image display regions of a display to be applied in the plane direction, and the mesh region. A conductor layer 12 having a grounding region 102 is formed on at least a part of the periphery of the substrate. The mesh area 101 has a size and shape that can cover the entire image display area of the applied display, and always includes a portion 30 that faces the image display area of the applied display. An outer edge portion that is an area outside the portion 30 that faces the image display area of the display may include the mesh area 101 or may include only the grounding area 102. The grounding region 102 normally has the same layer configuration as the mesh region 101 but does not form an opening, and is provided to facilitate grounding when installed on a display. The grounding region 102 may have a mesh shape in which an opening is formed. The grounding region 102 is often provided in a frame shape around the four sides in a portion that does not affect image display, which is an outer edge portion that is an outer region of the portion 30 facing the image display region of a rectangular display, The present invention is characterized in that it is provided not on the entire periphery of the mesh region 101 but on a part of the periphery and provided on only two sides or only one side. In the present invention, due to the characteristics of the manufacturing method, the grounding portion has at least one side edge in the width direction (y direction) when the electromagnetic shielding sheet is supplied as a continuous belt-like sheet. It is formed. In addition, at least a partial region of at least one of the side edges is formed by exposing the optical filter from the beginning at the time of lamination.
And when making the opposite side edge into a grounding region, it is preferable that the exposed width is approximately 1: 1 because the composite filter is symmetrical with respect to the center line.

As shown in FIG. 1B, the electromagnetic wave shielding sheet 1 of the present invention has a conductor layer 12 having a mesh region 101 and a grounding region 102 on one surface of a transparent substrate 11 in the thickness direction. Are at least laminated. The electromagnetic wave shielding sheet of the present invention may be formed by further laminating a non-conductive layer on the front and back surfaces of the conductor layer. Examples of the non-conductive layer include a rust preventive layer and a blackened layer that do not have conductivity.
Even if it is a rust prevention layer, a blackening layer, etc., when it has electroconductivity, it is contained in a conductor layer in this invention. The non-conductive layer further laminated on the front and back surfaces of the conductor layer is integrated with the conductor layer to form a mesh region and a grounding region.
In the present invention, the electromagnetic wave shielding sheet is prepared in the form of a continuous belt-like sheet, and is used in the form of a continuous belt in the process until it is cut into one unit corresponding to one display device.
Hereinafter, the electromagnetic wave shielding filter used in the present invention will be described in order from the transparent substrate 11.

[Transparent substrate]
The transparent substrate 11 is a layer for reinforcing a mesh layer 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 after considering heat resistance and the like as appropriate. Specific examples of the transparent substrate include a resin plate, a resin sheet (or a film, the same applies hereinafter), 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 resin is used as single or multiple types of mixed resin (a polymer alloy is included), and as a layer, it is used as a single layer or a laminated body 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 filler, a plasticizer, an antistatic agent, in these resins suitably as needed.

  In addition, what is necessary is just to set the thickness of a transparent base material according to a use, and there is no restriction | limiting in particular, When it consists of transparent resin, it is about 12-1000 micrometers normally, Preferably it is 50-500 micrometers. Within these thickness ranges, the mechanical strength is sufficient, there is no warp, slack, breakage, etc., and there is no cost increase due to excessive performance. Can be made thinner.

In addition, in order to continuously manufacture electromagnetic shielding filters and improve productivity, the transparent base material is in a stage until the entire lamination process of the composite filter is completed and the shape dimensions of one display device are determined. In this case, it is handled in the form of a continuous belt-like sheet.
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 have transparency, heat resistance, cost, and the like. In view of this, a biaxially stretched polyethylene terephthalate sheet is more preferable. In addition, although the transparency of a transparent base material is so good that it is good, 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.

[Conductor layer]
The conductor layer 12 is a layer having conductivity, and is a layer responsible for an electromagnetic wave shielding function. Even if the conductive layer 12 itself is opaque, the presence of an opening in a mesh shape causes an electromagnetic wave shield. It balances performance and light transmission. A perspective view of an example of the conductor layer 12 forming the mesh region 101 is shown in FIG. The conductor layer 12 forming the mesh region 101 has a mesh shape in which the openings 103 are closely arranged, and the mesh region has a line portion 104 that forms a frame that separates the openings 103 from each other. It is composed of

  In the present invention, the material and forming method of the conductor layer forming the mesh region and the grounding region are not particularly limited, and various conductor layers in a conventionally known conductor mesh type electromagnetic wave shielding sheet. Can be appropriately adopted. In general, the conductor layer mainly includes a metal layer, and in addition to this, includes a conductive treatment layer as will be described later, and, in some cases, a conductive blackening layer and a rust prevention layer.

  The shape of the mesh is arbitrary and not particularly limited, but the shape of the opening is typically a square. Examples of the shape of the opening include a triangle such as a regular triangle, a square such as a square, a rectangle, a rhombus, and a trapezoid, a polygon such as a hexagon, a circle, and an ellipse. The mesh has a plurality of openings having these shapes, and the openings are usually line-shaped line portions having a uniform width. Usually, the openings and the openings have the same shape and the same size over the entire surface. As an example of the specific size, the width of the line portion 104 between the openings (line width) is referred to as a line width T as shown in FIG. Preferably it is 50 micrometers or less. However, it is preferable to secure at least 5 μm or more for the expression of the electromagnetic wave shielding effect and prevention of breakage. The opening width of the opening is represented by (line pitch P) − (line width T), and is 100 μm or more, preferably 150 μm or more in the present invention. The line width T and the frontage width P are such that the aperture ratio = [(P−T) × (P−T) / P × P] × 100% is 60% or more. This is preferable because bubbles are less likely to remain in the opening during lamination with an optical filter described later. However, in order to exhibit electromagnetic wave shielding properties in the MHz to GHz band, the maximum aperture ratio is 3000 μm or less and 97% or less. In the present invention, the thickness of the finally obtained mesh region, that is, the height H of the line portion 104 between the openings is preferably 5 μm or less. In such a case, even when the step of flattening the mesh surface is omitted in advance before the lamination with the optical filter, the adhesive is placed in the opening of the metal mesh when the electromagnetic wave shielding sheet and the optical filter are laminated and bonded. This is because the layer easily enters uniformly, and bubbles do not easily remain in the opening. In this case, it is possible to avoid the disadvantage that the cloudiness value (haze) of the composite filter increases due to light scattering of the bubbles, and it is possible to obtain a composite filter with high transparency with high production efficiency. In consideration of the electromagnetic wave shielding function so that the electric resistance value of the metal is not increased and the electromagnetic wave shielding effect is not easily lost, it is more preferable that the height of the line portion of the mesh region is 1 to 3 μm. . In addition, the height of the line part of a mesh-like area | region says the total thickness including all the thickness of the layer which forms the line part 104. FIG. For example, when the line part 104 is composed of only a conductor layer, the height of the line part is equal to the thickness of the conductor layer. For example, the line part has a conductor layer, a non-conductive blackening layer, and a non-conductive layer. In the case of the conductive rust preventive layer, the height of the line portion is the total thickness of the conductor layer, the nonconductive blackened layer, and the nonconductive rust preventive layer. In addition, the bias angle of the mesh region (angle formed between the mesh line portion and the outer periphery of the electromagnetic wave shielding sheet) 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. .

A method for preparing such an electromagnetic wave shielding sheet in which a conductive layer having a mesh-like region is laminated is not particularly limited, and examples thereof include the following four methods.
(1) A method in which a conductive ink is printed in a pattern on a transparent substrate, and metal plating is performed on the conductive ink layer (for example, JP 2000-13088 A).
(2) A method in which a conductive ink or a chemical plating catalyst-containing photosensitive coating solution is applied to the entire surface of a transparent substrate, and the coating layer is made into a mesh by photolithography, followed by metal plating on the mesh (for example, , Sumitomo Osaka Cement Co., Ltd. New Materials Division, New Materials Research Institute, New Materials Research Group, “Photoresolvable Chemical Plating Catalyst”, [online], date not listed, Sumitomo Osaka Cement Co., Ltd. [2003 Search on January 7], Internet <URL: http://www.socnb.com/product/hproduct/display.html>).
(3) After laminating a transparent base material and a metal foil with an adhesive, the metal foil is formed into a mesh by a photolithography method (for example, JP-A-11-145678).
(4) On one surface of the transparent substrate, a metal thin film is formed by sputtering or the like to form a conductive treatment layer, and a transparent substrate on which a metal layer is formed as a metal plating layer by electrolytic plating is prepared. The metal plating layer and the conductive treatment layer of the metal-plated transparent base material are formed into a mesh shape by a photolithography method (for example, Japanese Patent No. 3502979, Japanese Patent Application Laid-Open No. 2004-241761).

  Among them, in the present invention, in particular, a thin film having a thickness of 5 μm or less, transparency and mesh accuracy are excellent, and a display image can be seen well. Further, in the manufacturing process, there is little warping or bubble mixing. It is particularly preferable to use the method (4) from the viewpoint of good yield and low cost in a short process. Then, the method to prepare the electromagnetic wave shielding sheet which has the conductor layer which forms the mesh-shaped area | region by the method of said (4) is demonstrated in detail.

  An example of an electromagnetic wave shielding sheet formed by the method (4) above, in which a conductor layer forming a mesh-like region is laminated on one surface of a transparent substrate, is shown in FIG. 3 is a cross-sectional view taken along line AA and BB in FIG. 3A shows a cross section that crosses the opening, and the openings 103 and the lines 104 are alternately formed. FIG. 3B shows a cross section that cuts the line 104 vertically, and the line 104 made of the conductor layer 12 is formed. Are formed continuously. In FIG. 3, the conductor layer 12 includes a conductive treatment layer 13 and a metal plating layer 14 (hereinafter, both are collectively referred to as a metal layer). In addition, in the cross-sectional views of the mesh-shaped region including FIG. 3, the height and width of the line portion 104 are greatly exaggerated much larger than other dimensions for the sake of clarity. It is.

(Formation of conductive treatment layer)
Since the transparent substrate 11 as described above is electrically insulating, when the method (4) is adopted, the surface of the transparent substrate 11 is subjected to a conductive treatment prior to metal electrolytic plating described later, and a conductive treatment layer is formed. Form. As a method for the conductive treatment, a thin film of a known conductive material may be formed. Examples of the conductive material include metals such as gold, silver, copper, iron, nickel, and chromium, or alloys of these metals (for example, nickel-chromium alloys). Moreover, transparent metal oxides, such as a tin oxide, ITO, and ATO, may be sufficient. The conductive treatment may be a single layer or a multilayer (for example, a laminate of a nickel-chromium alloy and a copper layer), and these materials are formed by a known vacuum deposition method, sputtering method, electroless plating method, or the like. The conductive treatment layer 13 is used. The thickness of the conductive treatment layer 13 is preferably an extremely thin layer of about 0.001 to 1 μm, as long as necessary conductivity can be obtained at the time of plating.

(Metal plating layer)
A metal plating layer 14 is formed on the surface of the conductive treatment layer 13 by electrolytic plating to form a metal-plated transparent substrate. As the material of the metal plating layer 14, for example, a metal having sufficient conductivity to shield electromagnetic waves, such as gold, silver, copper, iron, nickel, chromium, or an alloy containing these metals can be applied. The metal plating layer 14 may not be a simple substance, but may be a multilayer, and copper or a copper alloy is preferable from the viewpoint of ease of electrolytic plating and conductivity. In the present invention, since the height of the line portion of the mesh region is preferably 1 to 3 μm as described above, the thickness of the metal plating layer 14 is preferably about 2 μm at the maximum. If the height of the line portion of the mesh region is less than this, the electric resistance value of the metal is increased and the electromagnetic wave shielding effect tends to be impaired. The level difference of the part becomes large, and bubbles tend to remain when the adhesive layer is laminated.

(Blackening layer)
In order to absorb external light to the electromagnetic wave shielding sheet 1 and improve the visibility of the image on the display, a blackening process is performed on the observation side of the conductor layer 12 forming the mesh-like region, and the contrast is increased. It is preferable to improve the feeling. For this purpose, as shown in FIG. 4, a blackening layer 15A and / or 15B is provided on at least one surface of the metal plating layer 14 as necessary. The blackening layer is performed by either roughening the surface of the metal plating layer 14, providing light absorption over the entire visible light spectrum (blackening), or using both in combination. Further, when the conductive layer is formed by electrolytic plating, when the blackening layer 15A is provided on the surface of the transparent substrate 11, the following two methods are possible. (Method 1) A black conductive treatment layer 13 is provided on the transparent substrate 11, and this is also used as a blackening layer 15A. After that, a metal plating layer is formed on the blackening layer / conductive treatment layer 13 (15A). (Not shown). (Method 2) A transparent conductive treatment layer 13 such as ITO is provided on the transparent substrate 11, and a conductive blackening layer 15A is formed on the conductive treatment layer 11, and then a metal is formed on the blackening 15A. A plating layer is formed (the result is the layer structure of FIG. 4).

  As the blackening layers 15A and 15B, formation of metal oxides and metal sulfides and various methods can be applied. In the case of iron, it is usually exposed to steam at a temperature of about 450 to 470 ° C. for 10 to 20 minutes to form an oxide film (blackened film) of about 1 to 2 μm. An oxide film (blackened film) may be used. In the case of copper, a particle layer of copper-cobalt alloy, a nickel sulfide layer, a copper oxide layer, or the like is preferable.

  A preferable black density of the blackened layer is 0.6 or more. In addition, the measurement method of black density was set to the density standard ANSIT as an observation viewing angle of 10 degrees, an observation light source D50, and an illumination type using GRETAG SPM100-11 (trade name, manufactured by Kimoto Co., Ltd.) of COLOR CONTROL SYSTEM. The specimen is measured after calibration. Further, the light reflectance of the blackened layer is preferably 5% or less. The light reflectance is measured using a haze meter HM150 (trade name, manufactured by Murakami Color Co., Ltd.) in accordance with JIS-K7105. In addition, instead of measuring the reflectance, the Y value of reflection may be expressed by a color difference meter. In this case, the Y value is preferably 10 or less.

(Rust prevention layer)
Furthermore, it is preferable to provide the rust prevention layer 16B so that the surface of the metal plating layer 14 exposed on the outermost surface or the blackening layer 15B may be covered.
The rust prevention layer 16B is preferably provided on at least the blackening layer in order to prevent the rust prevention function and the blackening layer from dropping or deforming. As the rust prevention layer 16B, an oxide of nickel, zinc, and / or copper, or a chromate treatment layer can be applied. The nickel, zinc, and / or copper oxide may be formed by a known plating method, and the thickness is about 0.001 to 1 μm, preferably 0.001 to 0.1 μm.

  The blackening layers 15A and 15B may be provided at least on the observation side, and the contrast is improved and the visibility of the image on the display is improved. Further, it may be provided on the other surface, that is, on the display surface side, and stray light generated from the display can be suppressed, so that the visibility of the image is further improved.

Next, the process of making the conductor layer on the transparent substrate provided as described above into a mesh by a photolithography method will be described.
First, a conductive layer on a transparent substrate prepared as described above, for example, a metal layer (metal plating layer) 14 on a transparent substrate is provided with a resist layer, mesh-patterned, and not covered with a resist layer. After removing a portion of the metal layer 14 by etching, a mesh-like metal layer is formed by a so-called photolithography method in which the resist layer is removed. Furthermore, existing equipment can be used, and by performing many of these manufacturing processes continuously, quality is high, production efficiency is high, yield is high, and production can be performed at low cost.

(Photolithography method)
A resist layer is provided in a mesh pattern on the conductor layer surface of the laminate, and a portion of the conductor layer not covered with the resist layer is removed by etching, and then the resist layer is removed to form a mesh. .

(masking)
First, the surface on the conductor layer side of the laminate of the transparent base material 11 and the conductor layer 12 is made into a mesh shape by a photolithography method, and the mesh-like region 101 is formed. Also in this step, it is preferable to process a roll-shaped laminated body continuously wound in a band shape (referred to as a winding process or a roll-to-roll process). Masking, etching, and resist peeling are performed in a state where the laminate is stretched without looseness while being conveyed continuously or intermittently.

  First, in the masking, for example, a photosensitive resist is applied onto the conductor layer 12 forming the mesh-like region, and after drying, contact exposure with a predetermined pattern plate (photomask), water development, and dura Treat and bake. Note that either a negative type or a positive type of photosensitive resist can be used. When the photosensitive resist is a negative type, the mesh pattern of the pattern plate is a positive (positive image) with transparent line portions. When the photosensitive resist is positive, the mesh pattern of the pattern plate is a negative (negative image) with a transparent opening. Further, the exposure pattern is a desired pattern as an electromagnetic wave shielding sheet, and is composed of a pattern of a mesh area at a minimum. Further, as necessary, a grounding area pattern is added to the outer periphery of the mesh area as shown in FIG.

  In the winding of the resist, the conductive layer 12 that forms a mesh-like region while continuously or intermittently transporting a continuous belt-shaped laminated body (a laminated body of the transparent base material 11 and the conductive layer 12) is used in the winding process. A resist such as casein, PVA, or gelatin is applied to the surface by dipping (dipping), curtain coating, pouring, or the like. Moreover, a dry film resist may be used instead of application | coating, and workability | operativity can be improved. In the case of a casein resist, baking is performed at 200 to 300 ° C., but the lowest possible temperature is preferable in order to prevent warping of the laminate.

(etching)
Etching is performed after masking. As the etching solution used for the etching, a solution of ferric chloride or cupric chloride that can be easily circulated when etching is continuously performed is preferable. The etching is basically the same as the equipment for manufacturing a shadow mask for a color TV cathode ray tube that etches a strip-like continuous steel material, particularly a thin plate having a thickness of 20 to 80 μm. That is, the existing manufacturing equipment of the shadow mask can be diverted, and from masking to etching can be continuously produced continuously, which is extremely efficient. After etching, the substrate may be dried after washing with water, stripping the resist with an alkaline solution, and washing. Since the transparent base material is exposed on the surface of the mesh opening thus formed, the transparency of the mesh opening is good.

<(B) Step of preparing a continuous belt-like adhesive optical filter>
As the continuous band-like adhesive optical filter (B) according to the present invention (hereinafter also simply referred to as an optical filter), an adhesive layer is laminated on one surface, and the image of the display in the continuous band-like electromagnetic wave shielding sheet. A continuous belt-like shape having a shape and a width dimension X that covers all the part facing the display area and can expose at least a part of the grounding area on at least one of both end portions of the electromagnetic wave shielding sheet Prepare an adhesive optical filter. Here, as shown in FIG. 6, the width dimension X is a width in the (y) direction orthogonal to the longitudinal direction (x) to be continuously supplied, and is a width narrower than the width W of the electromagnetic wave shielding sheet. It takes a thing. Since the difference between the width W and the width X is the width of the grounding region, (W−X) is determined from the required area for grounding, the connection method with the conductive tape, and the like.

  A cross-sectional view of an example of the optical filter used in the present invention is shown in FIG. As shown in FIG. 5, the continuous band-like adhesive optical filter 20 used in the present invention is continuous in the longitudinal direction x with a width dimension X, and an adhesive layer 22 is laminated on one surface of the optical filter 21. The optical filter 21 is formed by laminating a transparent base material 23 and a function expressing layer 24. The functional expression layer is not particularly limited. For example, an optical filter functional layer such as a near-infrared absorbing layer, a neon light absorbing layer, an ultraviolet absorbing layer, an antireflection layer, or the like is essential, and a hard coat layer or an antifouling layer is used as necessary. An anti-glare layer is added. FIG. 5 exemplifies a case where the functional expression layer 24, the transparent base material 23, and the adhesive layer 22 are composed of three layers. Each of the functional expression layer, the transparent substrate, and the adhesive layer is illustrated as follows. There may be a single layer or a multilayer, and there may be a configuration in which the function-expressing layer and the transparent substrate are laminated to each other. In addition, the function-expressing layer may serve as the function of the transparent substrate, and may be composed of a function-expressing layer and an adhesive layer. Alternatively, an adhesive layer may be provided between each function expressing layer or between the function expressing layer and the transparent substrate. The optical filter used in the present invention has an adhesive layer on at least one surface and has adhesiveness. Therefore, it is not limited to the transparent substrate side, and there may be a configuration in which an adhesive layer is provided on the function expressing layer side.

[Layer structure of optical filter]
(Transparent substrate)
As the transparent substrate used for the optical filter, the same transparent substrate as described in the electromagnetic wave shielding sheet can be used.

(Functional expression layer)
Among the function expressing layers, as the near-infrared absorbing layer, a commercially available film having a near-infrared absorber (for example, Toyobo Co., Ltd., trade name No. 2832) is laminated with an adhesive, or a near-infrared absorbing dye is contained in the binder resin. May be applied. As the near-infrared absorbing dye, when an optical filter is applied to the front surface of a typical PDP, the near-infrared region generated when the PDP emits light using xenon gas discharge, that is, a wavelength of 800 nm to 1100 nm. It is preferable that the near-infrared transmittance in the band is 20% or less, more preferably 10% or less. At the same time, the near-infrared absorbing layer desirably has a sufficient light transmittance in the visible light region, that is, in the wavelength region of 380 nm to 780 nm. Specific examples of near-infrared absorbing dyes include polymethine compounds, cyanine compounds, phthalocyanine compounds, naphthalocyanine compounds, naphthoquinone compounds, anthraquinone compounds, imonium compounds, diimonium compounds, aminium compounds, pyrylium. Compounds, cerium compounds, squarylium compounds, copper complexes, nickel complexes, dithiol metal complexes organic near-infrared absorbing dyes, tin oxide, indium oxide, tungsten hexachloride, aluminum oxide, zinc oxide, iron oxide One or two or more inorganic near-infrared absorbing dyes such as these can be used in combination.
The binder resin may be a thermoplastic resin such as a polyester resin, a polyurethane resin, or an acrylic resin, a thermosetting resin or an ultraviolet curable resin made of a monomer such as epoxy, acrylate, or methacrylate, a prepolymer, or a hydroxyl group. A curable resin such as a two-component curable urethane resin utilizing a reaction between the alkenyl group and an isocyanate group can be used.

  Among the function expressing layers, the neon light absorbing layer is installed to absorb neon light emitted from the PDP when the optical filter is used for plasma display. The emission spectrum band of neon atoms is 550 to 640 nm, and it is preferable to design the light transmittance at a center wavelength of 590 nm to be 50% or less. The neon light absorption layer may be formed by dispersing a dye conventionally used as a dye having an absorption maximum in a wavelength region of at least 550 to 640 nm in a binder resin as mentioned in the near infrared absorption layer. it can. Specific examples of the dye include cyanine, oxonol, methine, subphthalocyanine or porphyrin.

  Of the function expressing layers, the ultraviolet absorbing layer can be formed by, for example, dispersing an ultraviolet absorbent in a binder resin. Examples of the ultraviolet absorber include organic compounds such as benzotriazole and benzophenone, and inorganic compounds composed of particulate zinc oxide, cerium oxide, and the like. As the binder resin, resins such as those listed for the near infrared absorption layer can be used.

  Moreover, as the antireflection layer (also abbreviated as AR (Anti Reflection) layer) among the function-expressing layers, for example, a multi-layer configuration in which low refractive index layers and high refractive index layers are alternately stacked is generally used. It can be formed by a dry method such as vapor deposition or sputtering, or by using a wet method such as coating. Note that silicon oxide, magnesium fluoride, fluorine-containing resin, or the like is used for the low refractive index layer, and titanium oxide, zinc sulfide, zirconium oxide, niobium oxide, or the like is used for the high refractive index layer. The reflected light is canceled by the light interference in the multilayer film.

In addition, as a hard coat layer (abbreviated as HC (Hard Coat) layer) among the function expressing layers, for example, polyfunctional (meth) such as polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, etc. An acrylate prepolymer, or a trifunctional or higher polyfunctional (meth) acrylate monomer such as trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, or the like It can be formed as a coating film using an ionizing radiation curable resin selected and combined in combination of two or more of monomers or prepolymers.
Here, (meth) acrylate is a composite notation meaning acrylate or methacrylate.

  In addition, as the anti-glare layer (also abbreviated as AG (Anti Glare) layer) among the function-expressing layers, a coating film formed by adding an inorganic filler such as silica in a resin binder, or a shaped sheet or a shaped plate, etc. Can be formed as a layer in which fine irregularities for irregularly reflecting external light are provided on the surface of the layer. As the resin of the resin binder, a curable acrylic resin, an ionizing radiation curable resin, or the like is preferably used in the same manner as the hard coat layer because surface strength is desired as the surface layer.

Of the function expressing layers, the antifouling layer is generally a water-repellent or oil-repellent coat, and a siloxane-based, fluorinated alkylsilyl compound or the like can be applied. A fluorine-based or silicone-based resin used as a water-repellent paint can be preferably used. For example, when the low refractive index layer of the antireflection layer is formed of SiO ₂ , a fluorosilicate water-repellent paint is preferably used.

(Adhesive layer)
Next, the adhesive layer which is an essential layer in the optical filter used in the present invention and is laminated on one surface will be described.
If the said adhesive bond layer is a layer which can adhere | attach the said optical filter and the said electromagnetic wave shielding sheet, the kind etc. will not be specifically limited, Various natural or synthetic resins are used, and it adheres. As a method, heat curing or ionizing radiation curing, heat fusion, adhesion, or the like can be applied.

Moreover, in this invention, it is especially preferable that it is an adhesive layer which has fluidity | liquidity at the time of adhesion | attachment with the said electromagnetic wave shielding sheet, and lamination | stacking. The fluidity mentioned here refers to the property of deforming or displacing indefinitely with little or no restoring force against external force. For example, Newton viscosity such as water, dilatancy or thixotropic (non-Newton) viscosity, or creep deformability is comprehensively referred to. In such a case, even if the mesh surface of the electromagnetic wave shielding sheet is not flattened, the adhesive layer spreads to every corner in the mesh opening during lamination and adhesion of the electromagnetic wave shielding sheet and the optical filter. Therefore, it is possible to prevent bubbles from remaining in the opening. Accordingly, it is possible to avoid the disadvantage that the haze value of the composite filter increases due to light scattering of bubbles while omitting the step of flattening the mesh surface, and it is possible to obtain a highly transparent optical filter with high production efficiency. . Accordingly, the fluidity of the adhesive layer in the present invention is such that the adhesive layer can be deformed to replace the air in the mesh region opening and fill the opening. The fluidity of the adhesive layer in the present invention is, as a guide, when the adhesive is pressed onto the mesh surface, 50,000 cps or less, preferably about 10000 cps (measured value with a C-type rotational viscometer. It is preferable to have a viscosity of a value of 2). Further, even when a low-flowing adhesive having a viscosity exceeding 50000 cps is used, if the adhesive layer is heated at the time of bonding and the air between the adhesive layer and the mesh surface is sucked in vacuum, the above-mentioned residual bubbles can be obtained. It can be resolved. However, after filling the mesh opening of the continuous band-shaped electromagnetic wave shielding sheet and laminating with the continuous band-shaped adhesive optical filter, the fluidity of the pressure-sensitive adhesive may be lowered as necessary. That is, at the time of adhesion with the electromagnetic wave shielding sheet, the fluidity of the pressure-sensitive adhesive is preferably higher for the purpose of reliably filling the mesh opening.
However, after adhesion and lamination, it is important that the pressure-sensitive adhesive does not have fluidity, and the pressure-sensitive adhesive flows out from the lamination interface between the electromagnetic wave shielding sheet and the adhesive optical filter, or a dye (colored) in the pressure-sensitive adhesive layer. A pressure-sensitive adhesive that does not promote discoloration of the dye when the agent is added may be selected and used. However, even with a low-fluidity adhesive, it is possible to prevent the bubbles from remaining by using heating and vacuum suction together with pressurization.

  As the adhesive layer having fluidity, it is sufficient that the adhesive layer has fluidity at the time of adhesion and lamination. For example, an adhesive layer made of a resin that has been fluidized (liquefied) by dissolving or dispersing in an adhesive or solvent, Even an adhesive layer composed of a natural rubber or synthetic resin that is fluid at room temperature without being dissolved or dispersed, or a syrup-type adhesive in which the polymer is dissolved in the reaction monomer Good. Further, it may be a hot-melt adhesive layer that is melted by applying an appropriate temperature and has fluidity. Further, it may be an adhesive layer containing a polymerization reactive monomer that is liquid at room temperature, and may be an adhesive layer that is cured by ultraviolet rays, heat, or the like after lamination. Among them, as a method for reducing the fluidity of the adhesive layer, for example, a cross-linking agent is added to the adhesive layer in advance and bonded to the electromagnetic wave shielding sheet. Examples of suitable methods include a polymerization method.

Among these, a pressure-sensitive adhesive is preferable as the fluid adhesive layer used in the present invention.
Here, the pressure-sensitive adhesive is a kind of adhesive. Of the adhesives, only adhesiveness on the surface is obtained only by pressing moderately, usually lightly by hand, at the time of bonding. It can be glued.
In order to develop the adhesive force of the pressure-sensitive adhesive, usually, physical energy or action such as heating, humidification, and radiation (ultraviolet ray, electron beam, etc.) irradiation is unnecessary, and no chemical reaction such as polymerization reaction is required.
Moreover, the pressure-sensitive adhesive can maintain the adhesive strength to the extent that it can be re-peeled even after bonding.
There is no restriction | limiting in particular as such an adhesive, It has moderate adhesiveness (adhesive force), transparency, and coating suitability from what is conventionally used as a well-known adhesive, and it is used in this invention. An optical filter that does not substantially change the transmission spectrum of the optical filter is appropriately selected.

  An acrylic adhesive is mentioned as an adhesive suitably used. The acrylic pressure-sensitive adhesive is a polymer containing at least a (meth) acrylic acid alkyl ester monomer. Generally, it is a copolymer of a (meth) acrylic acid alkyl ester monomer having an alkyl group having about 1 to 18 carbon atoms and a monomer having a carboxyl group. In the present invention, (meth) acrylic acid refers to acrylic acid and / or methacrylic acid.

Examples of (meth) acrylic acid alkyl ester monomers used here include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, sec-propyl (meth) acrylate, N-butyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, Examples thereof include n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, undecyl (meth) acrylate, and lauryl (meth) acrylate.
Moreover, the said (meth) acrylic-acid alkylester is copolymerized in the quantity of 30-99.5 weight part normally in an acrylic adhesive.

  Moreover, as a monomer which has a carboxyl group which forms an acrylic adhesive, monomers containing a carboxyl group such as (meth) acrylic acid, itaconic acid, crotonic acid, maleic acid, monobutyl maleate and β-carboxyethyl acrylate are used. Can be mentioned.

  Furthermore, in addition to the above, the acrylic pressure-sensitive adhesive used in the present invention may be copolymerized with a monomer having another functional group within a range not impairing the properties of the acrylic pressure-sensitive adhesive. Examples of monomers having other functional groups include monomers containing hydroxyl groups such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and allyl alcohol; (meth) acrylamide, N-methyl Monomers containing amide groups such as (meth) acrylamide and N-ethyl (meth) acrylamide; Monomers containing amide groups and methylol groups such as N-methylol (meth) acrylamide and dimethylol (meth) acrylamide; Monomers having functional groups such as monomers containing amino groups such as (meth) acrylate, dimethylaminoethyl (meth) acrylate and vinylpyridine; epoxy group-containing monomers such as allyl glycidyl ether and (meth) acrylic acid glycidyl ether Can be mentioned. In addition to these, fluorine-substituted (meth) acrylic acid alkyl ester, (meth) acrylonitrile, and the like, vinyl group-containing aromatic compounds such as styrene and methylstyrene, vinyl acetate, and vinyl halide compounds can be used.

Furthermore, in the acrylic pressure-sensitive adhesive used in the present invention, in addition to the monomer having other functional groups as described above, another monomer having an ethylenic double bond can be used. Examples of monomers having an ethylenic double bond include diesters of α, β-unsaturated dibasic acids such as dibutyl maleate, dioctyl maleate and dibutyl fumarate; vinyl esters such as vinyl acetate and vinyl propionate. Vinyl ether; vinyl aromatic compounds such as styrene, α-methylstyrene and vinyl toluene; (meth) acrylonitrile and the like.
In addition to the monomer having an ethylenic double bond as described above, a compound having two or more ethylenic double bonds may be used in combination. Examples of such compounds include divinylbenzene, diallyl malate, diallyl phthalate, ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, methylene bis (meth) acrylamide, and the like.

  Furthermore, in addition to the above-described monomers, monomers having an alkoxyalkyl chain can be used. Examples of alkoxyalkyl esters of (meth) acrylic acid include 2-methoxyethyl (meth) acrylate, methoxyethyl (meth) acrylate, 2-methoxypropyl (meth) acrylate, 3-methoxypropyl (meth) acrylate , 2-Methoxybutyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 4-ethoxybutyl (meth) acrylate And so on.

Moreover, the homopolymer of the (meth) acrylic-acid alkylester monomer may be sufficient. For example, (meth) acrylic acid ester homopolymers include poly (meth) acrylate methyl, poly (meth) ethyl acrylate, poly (meth) acrylate propyl, poly (meth) acrylate butyl, poly (meth) Examples include octyl acrylate.
As a copolymer containing 2 or more types of acrylate units, methyl (meth) acrylate- (meth) ethyl acrylate copolymer, (meth) methyl acrylate- (meth) butyl acrylate copolymer, ( Examples include methyl (meth) acrylate- (meth) acrylic acid 2-hydroxyethyl copolymer, methyl (meth) acrylate- (meth) acrylic acid 2-hydroxy-3-phenyloxypropyl copolymer, and the like.

As a copolymer of (meth) acrylic acid ester and other functional monomers, (meth) methyl acrylate-styrene copolymer, (meth) methyl acrylate-ethylene copolymer, (meth) acrylic An acid methyl- (meth) acrylic acid 2-hydroxyethyl-styrene copolymer may be mentioned.
For example, (meth) acrylic acid ester homopolymers include poly (meth) acrylate methyl, poly (meth) ethyl acrylate, poly (meth) acrylate propyl, poly (meth) acrylate butyl, poly (meth) Examples include octyl acrylate.
Examples of commercially available acrylic pressure-sensitive adhesives include Nos. TU-41A, TD-06, and Nitto Denko's No. 591, no. 5915, no. 5919M, no. 595B, CS9621, LA-50, LA-100, HJ-9210, HJ-9150W, etc. are preferably used.

  As the rubber-based adhesive, the main component is, for example, natural rubber, polyisoprene rubber, polyisobutylene, polybutadiene rubber, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, etc. Those containing at least one selected are used.

Moreover, it is preferable to mix | blend antioxidant, such as benzotriazole, with an adhesive bond layer. It is possible to prevent the color change from occurring due to oxidation of the conductive layer by the acid component contained in the adhesive at the interface between the adhesive layer and the conductive layer of the obtained composite filter.
Furthermore, a crosslinking agent such as an isocyanate compound, a tackifier, a silane coupling agent, a filler, and the like can be blended in the adhesive layer as desired.

  The adhesive layer may contain one or more near infrared absorbing dyes, ultraviolet absorbers, and / or neon light absorbing dyes as described above. By doing in this way, since the function of a plurality of functional layers can be combined with one layer and integrated with the adhesive layer, the total thickness, the number of processes, and the cost as a composite filter can be reduced. This is possible and preferable. In that case, it is preferable that the light transmittance in the wavelength region of 800 nm to 1100 nm is 20% or less, especially 10% or less, and the light transmittance in the wavelength region of 560 to 630 nm is 30% or less, especially 25% or less. .

[Shape and dimensions of optical filter]
Next, the shape and dimensions of the optical filter will be described.
The optical filter used in the present invention first covers the entire image display area of the display to be applied in order to uniformly exert the function of the optical filter over the entire area of the image display area of the applied display. Must have a shape and dimensions that are possible. Therefore, the optical filter used for this invention has the shape and dimension which can cover all the part 30 which opposes the image display area | region of the display of the said electromagnetic wave shielding sheet first.

  Here, the image display area refers to the entire area inside the frame by the outer frame when viewed from the display side of the display, outside the area that is substantially inside the frame and displaying the image. If there is a black area (border) that substantially does not display an image, it is outside the image display area. However, it is uncomfortable that the appearance is different from that of the image display area as long as the black area is also seen from the viewpoint of practical use. Therefore, for convenience, it is preferable to handle the black area by including it in the image display area. Moreover, the part 30 which opposes the image display area of the display of an electromagnetic wave shielding sheet is the area | region which faces an image display area so that all the image display areas of the applied display may be covered among the mesh-shaped area | regions 101 of an electromagnetic wave shielding sheet. This is an area having substantially the same shape and size as the image display area. Usually, in order to facilitate alignment with the image display area of the display, it is often slightly (a few millimeters) larger than the image display area of the display.

  The shape and dimensions of the optical filter used in the present invention are only required to be able to cover the entire portion 30 facing the image display area of the display of the electromagnetic wave shielding sheet, and have the same shape and the same as the image display area of the display. However, in order to facilitate alignment with the display image display area of the display and the portion of the electromagnetic shielding sheet facing the display image display area, it is usually slightly smaller than the display image display area. Make it larger. Therefore, the shape of the optical filter can be, for example, a shape that can cover the image display area of the display to be applied or the image display area of the display of the electromagnetic wave shielding sheet. In addition, as for the size of the optical filter, the width dimension X can be increased by, for example, about 1 mm to 20 mm, more preferably 1 mm to 10 mm, and particularly preferably about 2 mm to 5 mm, as compared with the image display area of the display to which the optical filter is applied.

  On the other hand, in the present invention, in order to secure a grounding portion on the electromagnetic wave shielding sheet at the same time as laminating the continuous band adhesive optical filter with the continuous electromagnetic wave shielding sheet, the optical filter used in the present invention is the electromagnetic wave shielding sheet. It has a shape and a dimension capable of exposing at least a part of the grounding region. The grounding region originally does not require mesh formation, but a mesh may be formed. Further, the exposed portion may include a part of the mesh region existing outside the portion facing the image display region of the display.

In order to have a shape and dimensions that can expose at least a part of the grounding region of the electromagnetic wave shielding sheet, the optical filter is one sheet when the electromagnetic wave shielding sheet is actually used as a composite filter for display. It is not possible to have the same shape and width dimensions as the entire area of the electromagnetic shielding sheet, and it is necessary to have a width dimension X smaller than the width W of the electromagnetic shielding sheet. However, it is only necessary that at least a part of the grounding region can be exposed. For example, as shown in FIG. 6A, there are lines that overlap the left and right edges of the region for one electromagnetic wave shielding sheet. The shape may be such that only the upper and lower edges become the exposed portion 40. The width dimension X of the optical filter is such that, for example, the upper and lower sides can be exposed, for example, 1 mm to 20 mm, more preferably 1 mm to 10 mm, and particularly preferably about 2 mm to 5 mm, as compared with the width W of the electromagnetic wave shielding sheet. That is, it is desirable to reduce the width dimension difference (W−X) by 2 to 40 mm, more preferably 2 to 20 mm, and particularly preferably 4 to 10 mm.
In the design of the display, as shown in FIG. 6 (B), when the grounding region is on both the left and right sides, a continuous band-shaped electromagnetic wave shielding filter that is continuous in the vertical direction in the figure may be prepared. The width dimension X of the optical filter is determined in the same manner as described above from the relationship with the width W in the left-right direction of the electromagnetic wave sheet.

<Exposure of electromagnetic shielding sheet edge>
In the method for producing a composite filter according to the present invention, the adhesive layer side of the continuous band-shaped adhesive optical filter is directed toward the conductor layer side of the electro-continuous band-shaped magnetic wave shielding sheet, and the continuous band-shaped adhesive optical filter is the above-mentioned In the state of covering the portion directly opposite the image display area of the display in the electromagnetic continuous electromagnetic wave shielding sheet and aligning so that one or both desired portions of the grounding area on both side edges in the width direction are exposed, The continuous band-like adhesive optical filter is bonded and laminated on the electric continuous band-like electromagnetic wave shielding sheet. Thereby, at least a part of the grounding region of the electromagnetic wave shielding sheet is exposed.

  A method for producing such a composite filter for display of the present invention will be specifically described with reference to the drawings. FIG. 7 is a process diagram illustrating one example of a stacking process of the manufacturing method of the composite filter for display according to the present invention. FIG. 7A1 shows a portion where the continuous band-like adhesive optical filter having the width dimension X is opposed to the image display region of the display in the electromagnetic wave shielding sheet having the width dimension W in a direction orthogonal to the continuously supplied longitudinal direction. It is sectional drawing which shows the state supplied continuously in the state aligned so that it may coat | cover just above, FIG. 7 (A2) is a top view which shows the state which performed the said position alignment.

  In this step, first, as shown in FIG. 7A1, the adhesive layer 22 side of the continuous band-like adhesive optical filter 20 is directed toward the conductor layer side 12 of the electromagnetic wave shielding sheet 1, and FIG. As shown in (A2), the continuous band-like adhesive optical filter 20 faces the image display area in the width direction directly above the portion 30 that faces the image display area of the display of the continuous band-like electromagnetic wave shielding sheet. The position is adjusted so as to cover all the portions 30 to be covered. When performing this alignment, it is preferable to increase the positional accuracy by attaching a register mark on the electromagnetic wave shielding sheet or using an optical sensor.

  In the state aligned as described above, next, as shown in FIG. 7 (B1), the adhesive layer 22 of the continuous band-like adhesive optical filter 20 is bonded and laminated to the continuous band-like electromagnetic wave shielding sheet 1. Then, at least a part of the grounding area of the electromagnetic wave shielding sheet 1 is exposed. The exposed portion 40 is not particularly limited as long as it is appropriately designed so as to enable grounding. However, a portion that does not affect the image display around the four sides of the rectangular electromagnetic shielding sheet is often provided in a frame shape. In the present invention, the entire periphery of the edge of the electromagnetic wave shielding sheet is not exposed, and two opposing sides or at least one side thereof may be exposed. Incidentally, in the form of FIG. 7, the grounding region 40 is exposed at both side edges. In FIG. 7, in order to simplify the illustration and description, in practice, a number of electromagnetic wave shielding sheets and optical filters for one unit are connected in the x direction in a continuous manner to form a continuous belt shape. Only the unit is extracted and illustrated. Actually, in the left-right direction of the composite filter of FIG. 7A2, there are a number of the same composite filters (for one unit) as shown in FIG. It is connected and connected. And after this adhesion | attachment and a lamination | stacking process, the continuous strip | belt-shaped composite filter with which the electromagnetic wave shielding sheet and the optical filter were laminated | stacked is cut | judged for every unit at a suitable time, and is sheet-ized. A single filter is installed in front of the display. Grounding is performed in the grounding area 40 at appropriate time points before and after that.

  The display composite filter of the present invention manufactured by the manufacturing method as described above does not have a step of removing other optical filter layers from the electromagnetic shielding sheet, which has been essential for grounding the composite filter. The electromagnetic shielding sheet can be exposed and grounded. Since there is no peeling and removing step that needs to be performed once for each display, mass production processing is possible and production efficiency is good.

  In particular, as the electromagnetic wave shielding sheet, the height of the line portion of the mesh-like region is 5 μm or less, the opening width of the mesh opening is 150 μm or more, and the mesh opening has no flattening layer coating. When using a continuous belt-like electromagnetic shielding sheet and using a continuous belt-like adhesive optical filter having a fluid adhesive layer at the time of adhesion and lamination as the continuous belt-like adhesive optical filter, the step of flattening the mesh region is performed. It is unnecessary, and it is possible to reduce unnecessary materials and processes, and to obtain a composite filter having excellent transparency with high production efficiency.

  The display composite filter obtained by the production method according to the present invention preferably has a high transparency, and preferably has a haze of 3 or less. Here, haze means a value measured by a method according to JIS K7105-1981.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

Hereinafter, the present invention will be specifically described with reference to examples.
<Example 1>
(1) Manufacture of electromagnetic wave shielding sheet The continuous strip | belt-shaped electromagnetic wave shielding sheet 1 shown as a unit in the top view of FIG. 1 (A) was produced as follows.
A continuous belt-like uncolored transparent biaxially stretched polyethylene terephthalate film having a thickness of 100 μm and a polyester resin primer layer formed on one side was prepared as the transparent substrate 11.
On the primer layer of the transparent substrate, a nickel-chromium alloy layer having a thickness of 0.1 μm and a copper layer having a thickness of 0.2 μm (a part of the conductor layer) are sequentially provided by sputtering. Treatment layer 13 was obtained.
A copper metal plating layer 14 (remaining portion of the conductor layer) having a thickness of 2.0 μm is provided on the surface of the conductive treatment layer by an electrolytic plating method using a copper sulfate bath, and the conductive treatment layer 13 and the metal plating layer are provided. Both layers 14 were formed as the conductor layer 12, and a continuous copper-clad laminate sheet was produced in which the conductor layer was directly formed on the transparent substrate without interposing the adhesive layer therebetween.

  Next, a blackened layer 15B was formed on the conductor layer. Specifically, a nickel plate is used for the anode, and the conductor layer is formed on a transparent substrate in a blackening plating bath made of a mixed aqueous solution of nickel ammonium sulfate aqueous solution, zinc sulfate aqueous solution and sodium thiocyanate aqueous solution. The laminated sheet thus immersed is subjected to electrolytic plating and blackening treatment, and a blackening layer 15B made of a nickel-zinc alloy is formed on the entire exposed conductor layer to form a conductor layer 12. A continuous sheet on which (the conductive treatment layer 13, the metal plating layer 14, and the blackening layer 15A) were laminated was obtained.

Next, the conductive layer of the laminated sheet is etched using a photolithography method, and the mesh region 101 including the opening 103 and the line portion 104, and the outer edge that surrounds the four circumferences of the mesh region 101. A frame-shaped grounding region 102 was formed in the part.
Specifically, using a production line for a color TV shadow mask, the etching was performed consistently from masking to etching on the continuous belt-like laminated sheet. That is, after applying a photosensitive etching resist to the entire conductor layer surface of the laminated sheet, a desired mesh pattern is closely exposed, developed, hardened, and baked, and on the area corresponding to the line portion of the mesh. After processing the resist layer into a pattern in which the resist layer remains and there is no resist layer on the area corresponding to the opening, the conductor layer and the blackened layer are removed by etching with an aqueous ferric chloride solution. A mesh-shaped opening was formed, and then water washing, resist peeling, washing, and drying were sequentially performed.

The mesh shape of the mesh region is such that the line width of the linear part whose opening is a square and non-opening is 10 μm, the line interval (pitch) is 300 μm, and the height of the line part is 2.3 μm. When cut into rectangular sheets as in (A), the bias angle defined as the subordinate angle of the line portion with respect to the long side of the rectangle was 49 degrees. Further, when the completed composite filter is mounted on the front surface of the image display device (display), a portion 30 that faces the image display region of the display exists in the mesh region 101, and the mesh region 101 At the peripheral edge, when the continuous belt-like sheet as a composite filter is cut, the pattern is designed such that an exposed portion having a width of 15 mm is left on the upper and lower sides as the grounding region 102 without opening.
In this way, an electromagnetic wave shielding sheet 1 of Example 1 having no flattening layer and having a width dimension W of 570 mm was obtained.

(2) Manufacture of continuous strip-like adhesive optical filter Next, the continuous strip-like adhesive optical filter 20 to be laminated on the continuous strip-like electromagnetic wave shielding sheet 1 was prepared. As the layer configuration of the optical filter, an anti-reflection layer / ultraviolet absorption layer / adhesive layer 22 (adhesive layer 22 also serves as a near infrared absorption layer and a neon light absorption layer) was prepared. “/” Indicates that the left and right layers are laminated and integrated.

As the ultraviolet absorbing layer, a Tetron film (trade name “HB type”, manufactured by Teijin Ltd.), which is a transparent biaxially stretched PET film having a width dimension X of 550 mm and a thickness of 50 μm, kneaded with an ultraviolet absorber. ) Was used. The ultraviolet absorbing layer was also used as a substrate for coating and forming an antireflection layer.
The antireflection layer was formed by sequentially forming a high refractive index layer and a low refractive index layer on the ultraviolet absorbing layer.
Here, the high refractive index layer is a cured product having a thickness of 3 μm and a refractive index of 1.69 of a composition (trade name “KZ7973” manufactured by JSR Corporation) in which ultrafine zirconia particles are dispersed in an ultraviolet curable resin. Consists of layers.
The low refractive index resin layer is made of a cured product having a thickness of 100 nm and a refractive index of 1.41 made of a fluororesin-based ultraviolet curable resin (trade name “TM086” manufactured by JSR Corporation).

Further, by forming an adhesive layer 22 on the side opposite to the antireflection layer side of the ultraviolet absorber layer, and adding a near infrared absorber and a neon light absorber in the adhesive layer 22, The adhesive layer was also used as a near infrared absorption layer and a neon light absorption layer.
A cyanine dye was added as a neon light absorber, and a diimonium dye and a phthalocyanine dye were added as a near infrared absorber.

As the adhesive, a low-flowing acrylic resin-based pressure-sensitive adhesive (manufacturer: Nitto Denko Corporation, trade name: CS9621) was used.
The optical filter 20 configured as described above has a shape that covers a portion 30 that faces the image display region on the mesh of the electromagnetic wave shielding sheet 1 and a portion (rectangle) that faces most of the left and right ground frame portions, and It was set as the continuous strip | belt-shaped adhesive optical filter 10 mm larger than an image display area and the width dimension 550mm.

(3) Manufacture of composite filter Then, the obtained continuous band-shaped electromagnetic wave shielding sheet 1 and the continuous band-shaped adhesive optical filter 20 are combined with the mesh in which the adhesive layer 22 is the conductor layer 12 as shown in FIG. The continuous adhesive optical filter covers the portion 30 facing the image display area of the mesh-like region 101 and the portion overlapping the left and right grounding frame portions, and facing the ground-like region 101. The inner peripheral side 2 mm of the upper and lower sides of the working region 102 is covered with the continuous adhesive optical filter, while the outer peripheral side 10 mm of the grounding region 102 of the upper and lower sides is not covered and the conductor layer is exposed. Then, the mesh region 101 and the adhesive layer 22 were bonded and laminated together. As a lamination condition at this time, the electromagnetic wave shielding sheet 1 and the continuous belt-like adhesive optical filter 20 are paired with a pair of sandwiched rubber rolls (iron cores) in the above alignment state via guide guides. Is surrounded by silicon rubber) with a maximum linear pressure of 10 kg / cm, while the heating and decompression chamber covering the nipping rubber roll is used with a vacuum pump, an electromagnetic wave shielding sheet, an optical filter, The air was sucked in between, and was laminated in a heated and pressurized state (so-called roll-to-roll processing) by blowing hot air at 80 ° C. from the continuous adhesive optical filter side.

<Example 2>
In the production of the composite filter of Example 1 (3), the composite filter was prepared in the same manner as in Example 1 except that lamination was performed at room temperature (20 ° C.) with a rubber roller at a maximum pressure of 10 kg / cm. Manufactured.

<Example 3>
In the production of the continuous band-like adhesive optical filter of Example 1 (2), an acrylic resin-based pressure-sensitive adhesive having high fluidity (manufacturer; manufactured by Yodogawa Paper, trade name: “TU-41A”) is used as an adhesive. A composite filter was produced in the same manner as in Example 1 except that it was used.

<Example 4>
In the production of the continuous belt-like adhesive optical filter of Example 2 (2), as an adhesive, an acrylic resin-based pressure-sensitive adhesive (manufacturer; manufactured by Yodogawa Paper Mill, trade name: “TU-41A”) is used. A composite filter was produced in the same manner as in Example 2 except that.

<Comparative Example 1>
In place of the continuous band-like adhesive optical filter of Example 1 (2), when the continuous band-like adhesive optical filter having the same width dimension X as the width dimension W of the electromagnetic wave shielding sheet is cut into sheets, the shape and The dimensions were the same as those of the electromagnetic wave shielding sheet 1 formed into a single sheet in the shape of FIG.
Further, when laminating the sheet-adhesive adhesive optical filter with the electromagnetic wave shielding sheet 1, both outer edges are aligned, and the sheet-adhesive adhesive optical filter is used for the ground region 101 on the mesh of the electromagnetic wave shielding sheet 1 and for grounding. Both regions 102 were covered over the entire area.
Others were processed in the same manner as in Example 1 to obtain a composite filter of Comparative Example 1.

<Comparative example 2>
Similarly to Comparative Example 1, the shape and dimensions of the single-wafer adhesive optical filter are the same as those of the single-wafer electromagnetic wave shielding sheet 1, and the single-wafer adhesive optical filter is a region 101 on the mesh of the electromagnetic wave shielding sheet 1. The composite filter of Comparative Example 2 was obtained by processing in the same manner as in Example 2 except that both the grounding region 102 and the grounding region 102 were laminated so as to cover the entire region.

<Comparative Example 3>
Similarly to Comparative Example 1, the shape and dimensions of the single-wafer adhesive optical filter are the same as those of the single-wafer electromagnetic wave shielding sheet 1, and the single-wafer adhesive optical filter is a region 101 on the mesh of the electromagnetic wave shielding sheet 1. The composite filter of Comparative Example 3 was obtained by processing in the same manner as in Example 3 except that both the grounding region 102 and the grounding region 102 were laminated so as to cover the entire region.

<Comparative example 4>
Similarly to Comparative Example 1, the shape and dimensions of the single-wafer adhesive optical filter are the same as those of the single-wafer electromagnetic wave shielding sheet 1, and the single-wafer adhesive optical filter is a region 101 on the mesh of the electromagnetic wave shielding sheet 1. The composite filter of Comparative Example 4 was obtained by processing in the same manner as in Example 4 except that both the grounding region 102 and the grounding region 102 were laminated so as to cover the entire region.

[Performance evaluation method]
The following points were evaluated with respect to the above examples and comparative examples. The evaluation results are shown in Table 1. From Table 1, in any of the embodiments of the present invention, the optical filter peeling work on the grounding area is unnecessary, so there is no problem in grounding work due to this. In addition, it is confirmed that by using a highly fluid material for the adhesive, or by applying heating and vacuum suction together with pressurization at the time of bonding, a product free of white turbidity due to residual bubbles in the mesh opening can be obtained. It was.
(1) Workability at the time of grounding The grounding work was performed on 10 samples. We compared the necessity of exposure work in the ground contact area, the complexity of the exposure work, and the degree of occurrence of defects.
[Criteria]
No exposure work required; ○
Exposure work is required. However, it can be reliably peeled every time, there is no breakage of the conductor layer every time;
Exposure work is required. However, it cannot be peeled once or more, or there is breakage damage to the conductor layer; ×

(2) Transparency of mesh-like region The composite filters were compared through visual observation.
Cloudy (cloudy) or those that do not recognize the presence of bubbles; ○
Appearance of cloudiness or air bubbles;
Appearance of cloudiness or bubbles, especially noticeable; ×

FIG. 1A is a plan view showing an example of an electromagnetic wave shielding sheet used in the present invention, and FIG. 1B is a cross-sectional view of an example of an electromagnetic wave shielding sheet used in the present invention. It is a perspective view which shows an example of the mesh-like area | region 101 of the conductor layer of this invention. It is a figure which shows an example of the electromagnetic wave shielding sheet used for this invention. It is a figure which shows another example of the electromagnetic wave shielding sheet used for this invention. It is a figure which shows an example of the optical filter used for this invention. It is a figure which shows an example of the exposed part of the electromagnetic wave shielding sheet in this invention. It is process drawing which shows an example of the adhesion | attachment of the manufacturing method of the composite filter for displays of this invention, and a lamination process as a unit. It is a figure which shows the continuous body immediately after lamination | stacking of the composite filter for displays of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic wave shielding sheet 11 Transparent base material 12 Conductor layer 13 Conductive treatment layer 14 Metal plating layer (metal layer)
DESCRIPTION OF SYMBOLS 15 Blackening layer 16 Rust prevention layer 20 Adhesive optical filter 21 Optical filter 22 Adhesive layer 23 Transparent base material 24 Function expression layer 40 (102) Grounding area 50 Composite filter 101 Mesh area 103 Opening part 104 Line part

Claims (5)

A method for producing a composite filter for a display comprising a laminate of an electromagnetic wave shielding sheet and an optical filter,
(A) A mesh-like region having a thickness of 5 μm or less capable of covering the entire image display region of the applied display on one surface of the transparent substrate and a part of at least one side edge around the mesh-like region A continuous band-shaped electromagnetic wave shielding sheet having a width dimension W formed by laminating at least a conductor layer having a grounding area;
(B) An adhesive layer is laminated on one surface to cover all portions of the electromagnetic wave shielding sheet facing the image display region of the display and to expose at least a part of the grounding region. A continuous strip-like adhesive optical filter having a width dimension X narrower than the width dimension W;
Directly above the part where the adhesive layer side of the continuous band-like adhesive optical filter faces the conductor layer side of the electromagnetic wave shielding sheet and the continuous band-like adhesive optical filter faces the image display area of the display in the electromagnetic wave shielding sheet characterized by continuously supplying to cover, bonded to the continuous strip-like adhesive optical filter to the electromagnetic shielding sheet, and then laminated, as a ground area at least one side edge of the electromagnetic shielding sheet, an exposing The manufacturing method of the composite filter for displays.   The method for producing a composite filter for display according to claim 1, wherein the electromagnetic wave shielding sheet has an opening width of 150 μm or more in an opening of a mesh region.   The manufacturing method of the composite filter for displays of Claim 1 or 2 which uses the continuous adhesive optical filter which has a fluid adhesive layer at the time of adhesion | attachment and lamination | stacking as said continuous strip adhesive optical filter.   The manufacturing of the composite filter for display according to any one of claims 1 to 3, wherein the grounding region is a side edge of the electromagnetic wave shielding sheet, and an exposed width of the side edge is approximately 1: 1. Method.   A composite filter for a display, which is obtained by the manufacturing method according to claim 1.

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