JP2009302439A - Light transmissive electromagnetic shield material and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light transmissive electromagnetic shield material having improved light transmittance and electromagnetic shielding performance without causing moire to occur. <P>SOLUTION: The light transmissive electromagnetic shield material has: a transparent substrate 110; and an electromagnetic shield layer 120 provided on the transparent substrate 110. In the light transmissive electromagnetic shield material, the electromagnetic shield layer 120 has a sea region structure in a sea-island structure, and the shapes of island regions 121 made of an opening surrounded by the electromagnetic shield layer 120 differ mutually. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a light-transmitting electromagnetic wave shielding material useful as a sticking sheet or the like that can be used for a front filter of a plasma display panel (PDP), a building window requiring an electromagnetic wave shield such as a hospital.

  In recent years, with the spread of OA equipment, communication equipment, etc., there is a concern about the influence on the human body caused by electromagnetic waves generated from these equipment. In addition, electromagnetic waves from a mobile phone or the like may cause malfunction of precision equipment, and electromagnetic waves are regarded as a problem.

  Therefore, a light-transmitting electromagnetic wave shielding material having an electromagnetic wave shielding property and a light transmitting property has been developed and put into practical use as a front filter for a PDP of an OA device. Such a light-transmitting electromagnetic wave shielding material is also used as a window material for installation of precision equipment such as hospitals and laboratories in order to protect precision equipment from electromagnetic waves.

  In this light-transmitting electromagnetic wave shielding material, it is necessary to make both light transmittance and electromagnetic wave shielding properties compatible. For this purpose, for example, a light-transmitting electromagnetic wave shielding material is used in which an electromagnetic wave shielding layer made of a conductive mesh in which a metal wire or a conductive fiber is made into a net is provided on one surface of a transparent substrate. Electromagnetic waves are shielded by the conductive mesh portion, and light transmission is ensured by the opening. In addition to this, a light-transmitting electromagnetic wave shielding material provided with an electromagnetic wave shielding layer made of a conductive mesh on a transparent substrate by etching a layer of copper foil or the like on a transparent substrate into a net shape and providing an opening. Etc. are also used.

  As described above, in the electromagnetic wave shielding layer, in order to achieve both excellent light transmittance and electromagnetic wave shielding properties, it is necessary to make the line width very small in the conductive mesh to form a very fine pattern. However, when the above-described conventional light-transmitting electromagnetic wave shielding material is disposed on the light-emitting panel, the periodic pattern of the pixel pitch and the conductive mesh in the light-emitting panel is overlapped to generate moire (interference fringes). This phenomenon makes the image very difficult to see.

  Therefore, in order to reduce the occurrence of moire, Patent Document 1 discloses a light-transmitting electromagnetic wave shielding material using a conductive mesh made of metal fibers having a wire diameter of 1 to 200 μm and an aperture ratio of 30 to 99.9%. Is disclosed. Moreover, in patent document 2, the light transmittance using the electroconductive mesh whose width | variety of the line which comprises a mesh is 3-18 micrometers, and the intersection thickness ratio in the intersection of the line which comprises a mesh is 2.0 or less. An electromagnetic shielding material is disclosed.

Japanese Patent Application Laid-Open No. 11-074684 JP 2004-221565 A

  As described above, in order to reduce the occurrence of moire in the light-transmitting electromagnetic wave shielding material, conventionally, means for adjusting the wire diameter, spacing, mesh shape, etc. of the conductive mesh have been used. However, in a conductive mesh having a certain period such as a lattice shape, there is a limit to the reduction in the generation of moire, and the generation of moire could not be sufficiently suppressed. Therefore, it is necessary to adjust the pattern so that the moire is not visible as much as possible by determining the pattern of the conductive mesh with respect to the pixel pitch in the light-emitting panel and adjusting the overlapping angle of the light-emitting panel and the conductive mesh. As a result, there was a problem that productivity was lowered.

  Accordingly, an object of the present invention is to provide a light-transmitting electromagnetic wave shielding material that is free from moire and has excellent light transmission and electromagnetic wave shielding properties.

  Another object of the present invention is to provide a method for producing the light transmissive electromagnetic wave shielding material.

  In this invention, it discovered that the said subject could be solved by making the shape of an electromagnetic wave shield layer into a sea island structure, and arrange | positioning the opening part for ensuring the transmission of light irregularly.

That is, the present invention is a light-transmitting electromagnetic wave shielding material having a transparent substrate and an electromagnetic wave shielding layer provided on the transparent substrate,
The electromagnetic shielding layer has a sea-island structure in plan view, and the electromagnetic shielding layer is formed in a sea region in the sea-island structure, and a plurality of island regions have openings, and the island region The above-mentioned problems are solved by a light-transmitting electromagnetic wave shielding material characterized in that the shapes of these are different from each other.

  Preferred embodiments of the light transmissive electromagnetic wave shielding material of the present invention are listed below.

(1) The island region has an irregularly bent and / or branched shape.
(2) The average width of the island region is 5 to 200 μm.
(3) The average width of the sea region is 5 to 200 μm.
(4) The sea region has a thickness of 0.1 to 40 μm.
(5) The aperture ratio of the electromagnetic wave shielding layer is 40 to 95%.
(6) The electromagnetic wave shielding layer is produced based on image data obtained by FM screening.
(7) The electromagnetic wave shielding layer is made of a metal including at least one selected from the group consisting of silver, copper, and aluminum.
(8) An optical filter for display using the light transmissive electromagnetic wave shielding material.
(9) A display in which the optical filter for display is bonded to the surface of an image display glass plate.

  In the light transmissive electromagnetic wave shielding material of the present invention, the electromagnetic wave shielding layer has a sea-island structure. Thus, when the electromagnetic wave shielding layer has an irregular pattern, the electromagnetic wave shielding property and the light transmittance are excellent, and the frequency of occurrence of moire is greatly reduced. Therefore, the light-transmitting electromagnetic wave shielding material can be manufactured without considering the pixel pitch in the light-emitting panel, and can be easily incorporated into a housing to be installed. .

  First, the light transmissive electromagnetic wave shielding material of the present invention will be described with reference to FIG. FIG. 1A is a cross-sectional view of the light transmissive electromagnetic wave shielding material of the present invention, and FIG. 1B is a plan view of a concavo-convex shape of a sea island structure possessed by the electromagnetic wave shielding layer of the light transmissive electromagnetic wave shielding material. .

  The light transmissive electromagnetic wave shielding material of the present invention includes a transparent substrate 110 and an electromagnetic wave shielding layer 120 provided on the transparent substrate 110 as shown in FIG. Further, as shown in FIG. 1B, the electromagnetic wave shielding layer 120 has a sea-island structure in plan view, and the electromagnetic wave shielding layer 120 is formed in the sea region in the sea-island structure. Has an opening 121 and the island regions have different shapes.

  Thus, the light-transmitting electromagnetic wave shielding material of the present invention has a pattern having no periodicity in which the electromagnetic wave shielding layer is formed in the sea region of the sea-island structure, and the shapes of the openings formed in the island region are different from each other. Have. Thereby, it is possible to highly suppress the occurrence of moire caused by light interference with the pixel pitch in the light-emitting panel. Furthermore, high electromagnetic shielding properties can be obtained by the sea region, and high light transmittance can be ensured by the island region including the opening. Therefore, the light transmissive electromagnetic wave shielding material of the present invention does not cause moire and has excellent light transmissive properties and electromagnetic wave shielding properties.

(Electromagnetic wave shielding layer)
The island region, that is, the opening in the electromagnetic wave shielding layer, preferably has an irregularly bent and / or branched shape. Accordingly, the electromagnetic shielding layer formed in the sea region also has an irregularly bent and / or branched shape, and a sea island structure in which the sea region and the island region are randomly bent and complicated can be obtained. . Therefore, it can be set as the electromagnetic wave shielding layer which does not have a fixed period, and generation | occurrence | production of a moire can be suppressed more highly.

  Moreover, although the island area which forms the said opening part may exist independently in the sea area, as shown to FIG. 1 (B), several island areas couple | bond together and are connected continuously. May be.

  The average width of the island regions in the sea-island structure, that is, the average width of the openings is preferably 5 to 200 μm, particularly 50 to 200 μm. Thereby, it can be set as the electromagnetic wave shielding layer which has sufficient light transmittance and is excellent in visibility.

  The average width of the sea region in the sea-island structure, that is, the average width of the electromagnetic wave shielding layer is preferably 5 to 200 μm, particularly preferably 5 to 50 μm. Thereby, it can be set as the electromagnetic wave shielding layer which has sufficient electromagnetic wave shielding property.

  In the present invention, the average width of the sea region and the average width of the island region are obtained by observing the electromagnetic wave shielding layer in the light transmissive electromagnetic wave shielding material with a magnification of about 1,000,000 times with an electron microscope (preferably a transmission electron microscope). Then, the width of the sea area or the island area is arbitrarily measured at least 100 locations, and the average value is obtained.

  The thickness of the sea region, that is, the thickness of the electromagnetic wave shielding layer is preferably 0.1 to 20 μm, particularly 1 to 8 μm. Thereby, the excellent electromagnetic wave shielding property can be ensured.

  The aperture ratio of the electromagnetic wave shielding layer is preferably 40 to 95%, particularly 50 to 60% in order to ensure sufficient electromagnetic wave shielding properties and light transmittance. The aperture ratio of the electromagnetic shielding layer refers to the area ratio occupied by the opening in the projected area of the electromagnetic shielding layer.

  The electromagnetic wave shielding layer having the above-described structure is preferably produced based on image data including an FM screen obtained by FM (Frequency Modulation) screening. The FM screen uses the number of dots arranged at random as grayscale expression. In the FM screen, the gradation level can be adjusted by FM screening using an FM screen program so that a plurality of dots are aggregated, and the sea-island structure as shown in FIG. Can be formed.

  In addition, the average width of the island region and the sea region in the electromagnetic wave shield layer can be adjusted by the size and number of dots on the FM screen.

  Since the electromagnetic wave shielding layer needs to have conductivity in order to obtain excellent electromagnetic wave shielding properties, the electromagnetic wave shielding layer is preferably made of a conductive material. As said electroconductive material, what is used for the electromagnetic wave shield layer in the conventional light transmissive electromagnetic wave shield layer can be used. For example, in addition to a metal, a conductive resin dispersed in a binder resin can be used.

  Examples of the conductive material include copper, stainless steel, aluminum, nickel, titanium, tungsten, tin, lead, iron, silver, carbon, or alloys thereof, preferably those made of metals such as copper, stainless steel, and nickel. Among these metals, it is particularly preferable to use a metal containing at least one selected from the group consisting of silver, copper and aluminum because an electromagnetic wave shielding layer can be easily formed by an FM screen and high electromagnetic wave shielding properties can be secured. .

  Alternatively, a conductive material in which conductive particles are dispersed in a binder resin can be used. Examples of the inorganic compound constituting the conductive particles include metals, alloys such as aluminum, nickel, indium, chromium, gold, vanadium, tin, cadmium, silver, platinum, copper, titanium, cobalt, and lead; or ITO, Indium oxide, tin oxide, zinc oxide, indium oxide-tin oxide (ITO, so-called indium-doped tin oxide), tin oxide-antimony oxide (ATO, so-called antimony-doped tin oxide), zinc oxide-aluminum oxide (ZAO; so-called aluminum dope) Examples thereof include conductive oxides such as zinc oxide). In particular, ITO is preferable. The average particle size is preferably 10 to 10,000 nm, particularly 10 to 50 nm.

  Examples of the binder resin include acrylic resin, polyester resin, epoxy resin, urethane resin, phenol resin, maleic acid resin, melamine resin, urea resin, polyimide resin, and silicon-containing resin. Furthermore, it is preferable that it is a thermosetting resin among these resins.

(Metal plating layer)
In the light-transmitting electromagnetic wave shielding material of the present invention, when it is desired to improve the electromagnetic wave shielding property by further reducing the electromagnetic wave shielding layer, it is preferable to further have a metal plating layer on the electromagnetic wave shielding layer.

  The metal plating layer can be formed by a known electrolytic plating method or electroless plating method. Generally, copper, copper alloy, nickel, silver, gold, zinc or tin can be used as the metal used for plating. These can be used alone or as two or more kinds of alloys. You may do it. Copper, copper alloy, silver, or nickel is preferable, and copper or copper alloy is particularly preferably used from the viewpoint of economy and conductivity.

(Blackening treatment layer)
Further, the electromagnetic wave shielding layer may be provided with antiglare performance. Therefore, in this invention, you may provide a blackening process layer on an electromagnetic wave shield layer and / or a metal plating layer by performing a blackening process to an electromagnetic wave shield layer and / or a metal plating layer. The blackening treatment can be performed by oxidation treatment, sulfurization treatment, black plating such as chromium alloy, or application of black or dark ink.

  The thickness of the blackening treatment layer is not particularly limited, but is 0.01 to 1 μm, preferably 0.01 to 0.5 μm. If the thickness is less than 0.01 μm, the antiglare effect of light may not be sufficient, and if it exceeds 1 μm, the apparent aperture ratio when viewed from the perspective may be reduced.

(Transparent substrate)
The transparent substrate on which the electromagnetic shielding layer having the sea-island structure described above is formed is not particularly limited as long as it is transparent (meaning “transparent to visible light”), but a plastic film is generally used. For example, polyester {eg, polyethylene terephthalate (PET), polybutylene terephthalate}, polymethyl methacrylate (PMMA), acrylic resin, polycarbonate (PC), polystyrene, triacetate resin, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyethylene, Examples thereof include ethylene-vinyl acetate copolymer, polyvinyl butyral, metal ion crosslinked ethylene-methacrylic acid copolymer, polyurethane, cellophane and the like. Among these, polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), etc. are highly resistant to loads during processing (heat, solvent, bending, etc.) and particularly highly transparent. preferable. In particular, PET is preferable because it has excellent processability.

  The thickness of the transparent substrate varies depending on the use of the light-transmitting electromagnetic wave shielding material or the like, but is generally 1 μm to 10 mm, 1 μm to 5 mm, particularly preferably 25 to 250 μm.

(Optical filter)
The light-transmitting electromagnetic wave shielding material of the present invention can be used as an optical filter for display by laminating further functional layers according to applications. Examples of the functional layer include a near infrared absorption layer, a hard coat layer, an antireflection layer, and a color tone adjustment layer. What is necessary is just to determine the lamination | stacking order of these functional layers in the optical filter for displays according to a use.

  The display optical filter may have a transparent adhesive layer for adhering to an electronic display.

  The near-infrared absorbing layer, hard coat layer, antireflection layer, color tone adjusting layer and transparent pressure-sensitive adhesive layer described above are the same as those used in conventionally known optical filters for displays, and are detailed here. Description is omitted.

  The display optical filter is used by being bonded to the surface of the image display glass plate of the display. The display includes a field emission display (FED) including a surface electric field display (SED), a liquid crystal display (LCD), a plasma display panel (PDP), a flat panel display (FPD) such as an EL display, and a CRT display. Can be mentioned.

  The light transmissive electromagnetic wave shielding material of the present invention can be produced by forming an electromagnetic wave shielding layer having the above-described sea-island structure on a transparent substrate using the following method.

(First manufacturing method)
As a first method for producing the light-transmitting electromagnetic wave shielding material of the present invention, a method using a photoresist method will be described with reference to FIG. In particular;
The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A different electromagnetic shielding layer is a method for producing a light transmissive electromagnetic shielding material formed on a transparent substrate,
A step (A) of forming an etching protective layer 230 on a portion of the metal film 222 corresponding to the sea region after forming the metal film 222 on the transparent substrate 210;
A step (B) of etching the exposed metal film 222 without forming the etching protective layer 230, and a step (C) of removing the etching protective layer 230,
A light-transmitting electromagnetic wave shielding material can be produced using a method including:

  In the step (A), the formation of the metal film on the transparent substrate is not particularly limited, but vapor deposition methods such as sputtering, ion plating, electron beam evaporation, vacuum evaporation, and chemical vapor deposition, It can be performed using a liquid phase film forming method such as electrolytic plating.

  In addition, about a transparent substrate, what was mentioned above in the light transmissive electromagnetic wave shielding material is used. Moreover, what was mentioned above in the electromagnetic wave shielding layer of a transparent electromagnetic wave shielding material is used also about the metal which comprises a metal film. The thickness of the metal film may be determined in consideration of the thickness of the obtained electromagnetic wave shielding layer.

  In the step (A), an etching protective layer is formed in a portion corresponding to the sea region composed of the electromagnetic wave shielding layer. As a result, as shown in FIG. 2, the opening 231 is formed in the portion corresponding to the island region formed of the opening in the electromagnetic wave shielding layer on the metal film without forming the etching protection layer. As such an etching protective layer, (i) a layer formed by printing an ink resistant to an etching solution on a metal film in a specific pattern, and (ii) a photocurable resin on the metal film A layer formed by exposing and developing a photoresist film formed by applying to a specific pattern can be used. In particular, the latter layer (ii) is preferably used because a fine pattern can be formed with high accuracy.

  As the photocurable resin, there is a conventional photosensitive resist. As the photosensitive resist, a negative type is used, and the exposed portion is cured and the non-exposed portion is not cured. Therefore, the non-exposed portion is developed by removing with a developer such as a solvent. Such photosensitive resists generally include polyvinyl cinnamate (solvent development), cyclized isoprene and bisazide (solvent development), polycinnamylidene acetate (solvent development), diallyl phthalate polymer (solvent development), cyclization There are polybutadiene type (solvent development), acrylic type (eg, monomer and oligomer having acryloyl group), and the like. Acrylics are binders (eg, poly (MMA-HEMA), ABS resin, triacetyl cellulose, polyacetal) and monofunctional or polyfunctional monomers, oligomers having ethylenic double bonds such as (meth) acryloyl groups, A composition in which a photopolymerization initiator is added to a polymer (eg, an acrylate copolymer) is used. Or the composition which can be made insoluble by light irradiation by adding the said monomer etc. to the water-soluble or alkali-soluble polymer which has photoreactive groups, such as an ethylenic double bond, can also be mentioned.

  The photo-curable resin is generally used by dissolving in an organic solvent when formed by coating, and a sheet-like one is used when pasting on a transparent substrate.

  The thickness of the photoresist film is preferably 0.1 to 20 μm, particularly preferably 0.5 to 5 μm. If it is thinner than 0.1 μm, the curability is inferior, and if it is thicker than 20 μm, it is difficult to obtain a thin line.

  The photoresist film produced as described above is exposed and developed to a portion corresponding to the island region formed of the opening of the electromagnetic wave shielding layer, that is, the island region and the plane formed of the opening of the electromagnetic wave shielding layer. Openings having the same visual shape and position are formed. As a result, a plating protective layer having the same shape and position in plan view as that of the sea region made of the electromagnetic wave shielding layer is formed in a portion corresponding to the sea region made of the electromagnetic wave shielding layer on the metal film.

  For example, when a photoresist film is formed on a metal film using a negative photosensitive resist, the photoresist film is a portion corresponding to the sea region in the sea-island structure of the electromagnetic wave shielding layer described above, For example, a method of removing the photoresist film in the non-exposed portion after exposing the portion corresponding to the island region as the non-exposed portion is used.

  Although the sea-island structure in the electromagnetic wave shielding layer is as described above, it is preferable that the shape of the island region formed of the opening of the electromagnetic wave shielding layer has an irregularly bent and / or branched shape. The shape of the opening in the layer is also preferably irregularly bent and / or branched.

  Therefore, in order to produce an etching protective layer in which an opening having such a specific pattern is formed, a photoresist film formed on a metal film is exposed imagewise based on image data obtained by FM screening. And it is preferable to produce by developing. As described above, by using the image data including the FM screen, the electromagnetic wave shielding layer having the sea-island structure shown in FIG. 1B can be easily and highly accurately formed.

  The photoresist film is exposed using, for example, a means for directly exposing the photoresist film imagewise with a laser light source or the like based on image data composed of an FM screen frequency-modulated by a computer using an FM screening program. Are preferred. It is also preferable to use a means for exposing the photoresist film imagewise with a laser light source or the like through a photomask having a light transmission portion formed on the basis of image data composed of an FM screen.

  FM screens such as Staccato (manufactured by CREO), Randot (manufactured by Dainippon Screen), RandotX (manufactured by Dainippon Screen), Stain Screening (manufactured by Heidelberg), and Crystal Raster (manufactured by Agfa) are commercially available. You can also use what you have.

  In order to form an electromagnetic wave shield layer having a sea-island structure as shown in FIG. 1B, dots are randomly generated by inputting numerical values necessary for the FM screening program when frequency modulation is performed. It is preferable to obtain an FM screen by adjusting the dots so that the dots are connected in a dense manner corresponding to the gray scale and connecting a plurality of dots.

  The shape of the dots constituting the FM screen may be any shape such as a polygon such as a triangle and a quadrangle, a circle, and an ellipse. Of these, a quadrangle, particularly a square is preferable.

  The dots constituting the FM screen are preferably quadrangles having a side length of 2 to 30 μm, particularly 15 to 30 μm. In the FM screen, the dot portion does not transmit light, and the portion other than the dot transmits light. Therefore, a dot portion, preferably an aggregate portion of a plurality of dots in the FM screen forms an opening in the photoresist film. Therefore, by making the shape of the dots constituting the FM screen as described above, it is possible to form an etching protective layer having an opening at a site corresponding to the island region formed from the opening of the electromagnetic wave shielding layer. .

  Further, the total area of dots with respect to the total area of the FM screen is preferably 20 to 60%, particularly preferably 40 to 50%. By setting the total area to 20% or more, an electromagnetic shielding layer having a sea-island structure in which a plurality of island regions are connected can be easily formed. By setting the total area to 60% or less, a high aperture ratio of the electromagnetic shielding layer is achieved. Can be secured.

  As a light source used for exposure, many light emitting in the ultraviolet to visible range can be adopted, for example, ultra-high pressure, high pressure, low pressure mercury lamp, chemical lamp, xenon lamp, halogen lamp, mercury lamp, carbon arc lamp, incandescent A lamp, a laser beam, etc. are mentioned. The irradiation time cannot be determined unconditionally depending on the type of lamp and the intensity of the light source, but is about several seconds to several minutes.

  The photoresist layer is exposed imagewise using an FM screen and then developed to remove the unexposed photoresist film. The development can be performed using a conventionally known method, for example, a means for immersing the entire laminate including a transparent substrate, a metal film, and a photoresist layer in a photoresist removal treatment solution such as a sodium carbonate aqueous solution. Can be used.

  The photoresist layer obtained as described above preferably has a sea-island structure similar to that shown in FIG. Further, the width of the photoresist layer, the opening of the photoresist layer, and the aperture ratio in the photoresist layer may be determined so that a desired electromagnetic wave shielding layer can be obtained.

  In the case of using a layer formed by printing (i) an ink resistant to an etching solution on a metal film in a specific pattern as an etching protective layer, the ink is used as described in (ii) above. It is preferable to perform image-like printing based on image data obtained by FM screening as in the case of the above layer. As the printing method, for example, an inkjet method can be used. As the image data obtained by the FM screening, the same data as the layer (ii) described above is used.

  Next, in the step (B), the metal film exposed in the opening of the etching protective layer is etched.

  The etching can be performed using a conventionally known method. For example, it can be performed using an etchant such as iron chloride, copper chloride, ammonia sulfate, ammonia alkali, chromium sulfate, nitric acid, or the like.

  Next, the etching protective layer is removed in step (C). As a result, as shown in FIG. 2, an electromagnetic wave shielding layer 220 made of metal is formed in the sea region of the sea island structure on the transparent substrate 210, and the openings 221 are formed in the sea region in different shapes. The light-transmitting electromagnetic wave shielding material of the present invention is obtained.

  The removal of the photoresist layer can be performed using, for example, an aqueous sodium hydroxide solution.

(Second manufacturing method)
As a manufacturing method of the light-transmitting electromagnetic wave shielding material of the present invention, the following second manufacturing method can be used in addition to the above-described method. The method will be described below with reference to FIG. In particular;
The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A different electromagnetic shielding layer is a method for producing a light transmissive electromagnetic shielding material formed on a transparent substrate,
A step (A) of forming a mask layer 340 on a portion of the transparent substrate 310 corresponding to the island region by printing a printing ink containing a material soluble in a solvent;
Forming a conductive material layer 322 containing a conductive material insoluble in the solvent on the transparent substrate 310 having the mask layer 340; and
(C) forming the electromagnetic wave shielding layer 320 by removing the mask layer 340 and the conductive material layer 344 on the mask layer 340 with the solvent;
It is a method including.

  In the printing ink used in the step (A), the material soluble in the solvent is selected according to the solvent used for the subsequent removal. For example, when an aqueous solvent is used as the solvent, a water-soluble substance is used, and when an oil-based solvent is used as the solvent, an oil-soluble substance is used. Examples of the solvent include known organic solvents, but water is particularly preferable in consideration of the low cost and the influence on the environment. The water may be an aqueous solution containing an organic solvent soluble in water (eg, alcohol such as methanol or ethanol), an acid, an alkali, or a surfactant in addition to normal water. A combination of water and methanol is preferable, and the ratio is preferably 5:95 to 50:50 by mass ratio.

  When the solvent is water, the material soluble in the solvent includes water-soluble polymer materials such as water-soluble resins such as polyvinyl alcohol, hydroxyethyl cellulose, carboxymethyl cellulose, polyethylene oxide, polyacrylamide, and polyvinylpyrrolidone. In particular, polyvinyl alcohol is preferable in that it has good water solubility. The molecular weight of the water-soluble resin is generally 10,000 to 100,000 (number average molecular weight by GPC), particularly preferably 29000 to 40,000. In particular, when polyvinyl alcohol is used, the polymerization degree is generally 300 to 1500, particularly 500 to 1000, and the saponification degree is preferably 85 to 90. If desired, the material used for forming this pattern may be mixed with a pigment, a dye or the like in order to make it easy to confirm the finished state. Examples of the pigment include barium sulfate, calcium carbonate, silica, mica, and clay, but barium sulfate is preferable. The pigment is preferably in the range of 20 to 200% by mass and 20 to 150% by mass with respect to the resin.

  The density | concentration of the material soluble with respect to the solvent in printing ink should just be about 5-50 mass%. In the printing ink, water is preferably used as a solvent, but alcohols, preferably lower alcohols such as ethyl alcohol, isopropyl alcohol, and normal propyl alcohol may be used in combination for the purpose of drying preparation.

  In the step (A), a mask layer is formed on a portion corresponding to the island region formed from the opening in the electromagnetic wave shielding layer on the transparent substrate by printing the above-described printing ink. In order to produce such a mask layer, a conventionally known method can be appropriately used. For example, there is a method of printing a printing ink using (i) a concave plate in which a concave pattern corresponds to an island region, or (ii) a screen printing plate in which an opening pattern corresponds to an island region. Preferably used.

(I) To produce a concave plate in which the pattern of the concave portion corresponds to the island region, for example, as shown in FIG.
A step (1) of forming a photoresist layer 480 having a pattern in which openings 481 are formed in portions corresponding to island regions on the printing plate base material 470, and printing exposed in the openings 481 (2) forming a printing plate having ink containing cells 461 by removing the photoresist layer 480 after etching a part of the plate base 470;
A method including the above can be used.

  In the said process (1), if it is a well-known thing in printing methods, such as the conventional gravure, as a printing plate base material used, it can be used without a restriction | limiting. For example, as shown in FIG. 4, a metal plate 460 formed on a metal substrate 450, such as a metal substrate made of steel, aluminum, or iron, a copper plating film formed, or the like. Can be mentioned. Moreover, the shape of the base material for printing plates should just be well-known shapes, such as flat form or cylinder shape, However, When using gravure printing, it has a cylinder shape generally.

In order to form the photoresist layer having the above-mentioned specific pattern on the printing plate substrate, for example, a method of exposing and developing the photoresist film can be used. When performed using the method, the step (1) includes:
(1-1) a step of forming a photoresist film on the printing substrate; and (1-2) a portion corresponding to the sea region formed by the electromagnetic wave shielding layer is used as an exposed portion of the photoresist film. The step corresponding to the island region formed from the opening in the electromagnetic wave shield layer is exposed as a non-exposed portion, and then the photoresist film in the non-exposed portion is removed.

  In addition, about the said photoresist film, since the thing similar to the photoresist film in the method mentioned above is used as a 1st manufacturing method of a light transmissive electromagnetic wave shielding material, detailed description is abbreviate | omitted here.

  The specific pattern described above in the photoresist layer is preferably formed based on image data obtained by FM screening. By using the FM screen in this manner, the electromagnetic wave shielding layer having the sea-island structure shown in FIG. 1B can be formed easily and with high accuracy. Therefore, the exposure of the photoresist film in the step (1-2) is preferably performed based on image data including an FM screen obtained by FM screening, for example. Also for the exposure and development of the photoresist film, since the same method as the above-mentioned step (B) is used as the first manufacturing method of the light-transmitting electromagnetic wave shielding material, detailed description is omitted here.

  The shape of the dots constituting the FM screen may be any shape such as a polygon such as a triangle and a quadrangle, a circle, and an ellipse. Of these, a quadrangle, particularly a square is preferable.

  The dots constituting the FM screen are preferably quadrangles having a side length of 2 to 30 μm, particularly 15 to 30 μm. In the FM screen, the dot portion does not transmit light, and the portion other than the dot transmits light. Therefore, the dot portion in the FM screen, preferably an aggregate portion of a plurality of dots, forms an opening in the photoresist layer. Therefore, by making the shape of the dots constituting the FM screen as described above, it is possible to form a photoresist layer having an opening in a portion corresponding to the island region formed from the opening of the electromagnetic wave shielding layer. .

  Further, the total area of dots with respect to the total area of the FM screen is preferably 20 to 60%, particularly preferably 40 to 50%. By setting the total area to 20% or more, an electromagnetic shielding layer having a sea-island structure in which a plurality of island regions are connected can be easily formed. By setting the total area to 60% or less, a high aperture ratio of the electromagnetic shielding layer is achieved. Can be secured.

  Next, in the step (2), first, a part of the printing plate substrate exposed at the opening in the photoresist layer can be etched using a conventionally known method. For example, it can be performed using an etchant such as iron chloride, copper chloride, ammonia sulfate, ammonia alkali, chromium sulfate, nitric acid, or the like.

  In the step (2), after the etching, the patterned photoresist layer can be removed using, for example, an aqueous sodium hydroxide solution.

  According to the step (2), a concave plate having a concave pattern corresponding to an island region which is an opening in the electromagnetic wave shielding layer can be formed. The opening in the concave plate functions as an ink containing cell. In the method, it is preferable that the shape of the concave plate patterned in this way has a structure similar to the sea-island structure as shown in FIG. In the second method, the opening in the concave plate corresponds to an island region made up of the opening in the mask layer and the electromagnetic wave shielding layer produced in a later step. Further, the width of the island region formed of the photoresist layer and the opening of the photoresist layer, and the aperture ratio in the photoresist layer may be determined so that a desired electromagnetic wave shielding layer can be obtained.

  Using the intaglio plate produced as described above, a printing ink containing a material soluble in a solvent is printed on the transparent substrate, thereby forming a mask layer on a portion corresponding to the island region of the transparent substrate. In this case, a printing method such as a conventionally known gravure printing method may be used. For example, after printing ink containing a material soluble in a solvent is applied to the intaglio, the printing ink contained in the depression of the intaglio is transferred onto the transparent substrate by bringing the ink into contact with the transparent substrate. Done.

  In this way, by printing the printing ink on the transparent substrate using the intaglio, the width of the mask layer that can be wet and spread although the printing ink is slightly on the transparent substrate is widened, thereby forming in a later process. The width of the electromagnetic wave shielding layer can be made fine.

  In addition, (ii) in order to produce a screen printing plate in which the pattern of the opening used in the step (A) corresponds to the island region, the opening in which the mesh substrate is exposed in the portion corresponding to the island region For example, a method of forming a photoresist layer having a pattern having a pattern on a mesh substrate is used.

  In order to form a photoresist layer having such a specific pattern, a method similar to the above-described concave plate is used.

  The mesh base material is not particularly limited as long as it is a conventionally known material used in screen printing. There are resin fibers such as silk, nylon, and polyester, and a stainless mesh, but when printing accuracy is required, a stainless mesh with little expansion and contraction and good dimensional accuracy is used. For example, a stainless steel wire having a wire diameter of 14 μm expressed as SS380-14 and having a density of 380 per 25.4 mm (1 inch) and a plain weave mesh is used.

  Using the screen printing plate produced as described above, a printing layer containing a solvent-soluble material is printed on the transparent substrate, whereby a mask layer is formed on the portion corresponding to the island region of the transparent substrate. The formation may be performed in the same manner as a conventionally known screen printing method.

  Further, as a printing method of the printing ink in the step (A), in addition to the above-described method using the concave plate or the screen printing plate, the printing ink is used for the FM screen in the same manner as the concave plate or the screen printing plate described above. It is also possible to perform image-like printing based on the image data obtained by the ning. As the printing method, for example, an inkjet method can be used.

  In the step (A), the printing ink printed on the transparent substrate is preferably dried. The drying may be performed by leaving at room temperature, or may be performed by heating at 90 to 130 ° C. for 2 to 10 seconds. Thereby, the mask layer formed using the printing ink on the transparent substrate is obtained. The thickness of the mask layer may be about 0.1 to 5 μm.

  In the method of the present invention, as described above, the mask layer is formed on the transparent substrate in the step (A). In order to improve the adhesion between the mask layer and the transparent substrate, the adhesive layer is formed on the transparent substrate. It is preferable to form a mask layer on the adhesive layer.

  The said adhesive layer is a layer for improving the adhesiveness of a transparent substrate, the mask layer formed in a post process, and an electromagnetic wave shield layer. For the adhesive layer, for example, a general adhesive such as an epoxy resin, a polyester resin, an acrylic resin, a urethane resin, or an epoxy urethane copolymer resin can be used, but a thermosetting adhesive is preferably used. .

  In order to form the adhesive layer on the transparent substrate, a solution obtained by dispersing or dissolving the adhesive in a solvent may be applied to the transparent substrate with a suitable coater such as a coater and then dried.

  The thickness of the adhesive layer is preferably 3 to 10 μm, particularly 4 to 8 μm. Thereby, sufficient adhesiveness can be ensured.

  Next, in the method of the present invention, the step (B) of forming a conductive material layer containing a conductive material insoluble in a solvent on a transparent substrate having a mask layer is performed. The conductive material is preferably a metal or alloy such as aluminum, nickel, indium, chromium, gold, vanadium, tin, cadmium, silver, platinum, copper, titanium, cobalt, lead, or a conductive metal oxide such as ITO. is there. If the thickness of the conductive material layer is too thin, the electromagnetic shielding performance is insufficient, which is not preferable. If the thickness is too thick, the thickness of the light-transmitting electromagnetic shielding material obtained is affected and the viewing angle is narrowed. Therefore, the thickness is preferably about 0.5 to 100 μm.

  Methods for forming the conductive material layer include sputtering methods, ion plating methods, vacuum deposition methods, chemical vapor deposition methods and the like (vapor phase plating methods), liquid phase plating methods (electrolytic plating, electroless plating, etc.), printing, and coating. As exemplified, vapor phase plating (sputtering, ion plating, vacuum deposition, chemical vapor deposition) or liquid phase plating in a broad sense is suitable.

  When the conductive material layer is formed by coating, as an insoluble conductive material, metal and / or metal compound particles having a particle size of 1 μm or less (preferably metal and / or metal compound particles, particularly silver oxide particles or organic silver particles) ), And a coating solution containing these is applied and dried.

  Next, in the method of the present invention, the step (C) of forming the electromagnetic wave shielding layer is performed by removing the mask layer and the conductive material layer on the mask layer with a solvent.

  As the solvent to be brought into contact with the mask layer, a solvent in which a material soluble in the solvent used for forming the mask layer may be used, and an organic solvent or water, preferably water.

  After immersing the transparent substrate on which the mask layer is formed in a solvent, or after applying the solvent to the transparent substrate on which the mask layer is formed, the mask layer is preferably rubbed with a sponge or a brush to rub the mask layer. Can be removed.

(Third production method)
As a manufacturing method of the light-transmitting electromagnetic wave shielding material of the present invention, the following third manufacturing method can be used in addition to the above-described method. Below, the said method is demonstrated, using FIG. In particular;
The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A method for producing a light-transmitting electromagnetic wave shielding material in which different electromagnetic wave shielding layers are formed on a transparent substrate via an electroless plating catalyst layer,
A step (A) of producing an electroless plating catalyst layer 590 on the transparent substrate 510;
A step (B) of forming a plating protective layer 540 on a portion corresponding to the island region of the electroless plating catalyst layer 590 by applying a printing ink containing a synthetic resin;
A step (C) of forming an electromagnetic wave shielding layer 520 by electroless plating on the electroless plating catalyst layer 590 exposed without forming the plating protective layer 540;
Can be used.

  In the step (A), in order to produce the electroless plating catalyst layer, means for applying and drying the electroless plating catalyst ink on the entire surface of at least one surface of the transparent substrate is used.

  As the electroless plating catalyst ink, an ink containing a mixture or reaction product of a silane coupling agent and an azole compound and a noble metal compound is used.

  As the silane coupling agent used in the electroless plating catalyst ink, it is preferable to use a silane coupling agent having a functional group having a metal capturing ability in one molecule. This makes it possible to achieve an electronic state and orientation that effectively expresses the activity of the noble metal compound that is the electroless plating catalyst, and high adhesion to the material to be plated is obtained.

  An example of the silane coupling agent is an epoxy group-containing silane compound. Examples of the epoxy group-containing silane compound include γ-glycidoxypropyltrialkoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropyltriethoxysilane. , 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the like. These may be used alone or in combination of two or more. In particular, γ-glycidoxypropyltrialkoxysilane is preferably used because the obtained electroless plating catalyst layer has high light transmittance.

  Next, as the azole compound used in the electroless plating catalyst ink, imidazole, oxazole, thiazole, selenazole, pyrazole, isoxazole, isothiazole, triazole, oxadiazole, thiadiazole, tetrazole, oxatriazole, thiatriazole , Benzazole, indazole, benzimidazole, benzotriazole, indazole and the like. Although not limited to these, imidazole is particularly preferable because it is excellent in reactivity with a functional group such as an epoxy group of the silane coupling agent and a noble metal compound.

  In the electroless plating catalyst ink, the silane coupling agent and the azole compound may be simply mixed, or may be reacted in advance to form a reaction product. Thereby, while being able to disperse | distribute a noble metal compound more highly in an atomic level in an electroless-plating catalyst layer, the light transmittance of the obtained electroless-plating catalyst layer can be improved.

  In order to react the silane coupling agent with the azole compound, for example, 0.1 to 10 mol of silane coupling agent is mixed with 1 mol of azole compound at 80 to 200 ° C. for 5 minutes to It is preferable to react for 2 hours. At that time, a solvent is not particularly required, but an organic solvent such as chloroform, dioxanemethanol, ethanol or the like may be used in addition to water. The electroless plating catalyst ink is obtained by mixing a noble metal compound with the reaction product of the silane coupling agent and the azole compound thus obtained.

  Next, the noble metal compound used in the electroless plating catalyst ink exhibits a catalytic effect capable of selectively depositing and growing a metal such as copper or aluminum from the electroless plating solution. Specifically, it is preferable to use a compound containing a metal atom such as palladium, silver, platinum and gold because high catalytic activity is obtained. Examples of the compound include chlorides, hydroxides, oxides, sulfates, ammonium salts, and the like of the metal atom, and palladium compounds, particularly palladium chloride is preferable.

  The electroless plating catalyst ink preferably contains 0.001 to 50 mol%, more preferably 0.1 to 20 mol% of the noble metal compound with respect to the azole compound and the silane coupling agent. If the concentration of the noble metal compound is less than 0.001 mol%, sufficient catalytic activity may not be obtained, and an electromagnetic wave shielding layer having a desired thickness may not be formed. There is a risk that the catalytic effect of the noble metal compound cannot be obtained.

  The electroless plating catalyst ink may contain a suitable solvent. Examples of the solvent include water, methyl alcohol, ethyl alcohol, 2-propanol, acetone, toluene, ethylene glycol, polyethylene glycol, dimethylformamide, dimethyl sulfoxide, and dioxane. These may be used individually by 1 type and may be used in mixture of 2 or more types.

  The electroless plating catalyst ink may further contain an additive such as a surfactant as necessary.

  As a method of applying the electroless plating catalyst ink on at least one entire surface of the transparent substrate, gravure reverse, gravure coat, micro gravure coat, lip coat, roll reverse coat, wire bar coat, kiss coat, die coat, roll coat, Methods such as spin coating, air spraying, airless spraying, dipping, and brushing are common, but are not limited thereto.

  The electroless plating catalyst ink transferred onto the transparent substrate is preferably dried by heating to 80 to 160 ° C, more preferably 120 to 140 ° C. When the heating temperature is less than 80 ° C., the evaporation rate of water is slow and there is a possibility that sufficient film forming properties cannot be obtained. On the other hand, if the temperature exceeds 160 ° C., the electroless plating catalyst layer forming material may be thermally decomposed to reduce adhesion, and may be discolored to reduce light transmittance. The drying time is preferably 1 second to 5 minutes.

  Next, in the method of the present invention, by printing a printing ink containing a synthetic resin, on the portion corresponding to the island region of the electroless plating catalyst layer, that is, the island region and the plane of the electroless plating catalyst layer Step (B) of forming a plating protective layer having the same visual shape and position is performed.

  The printing ink can be printed using a conventionally known method. For example, a printing ink is printed using (i) a concave plate in which a concave pattern corresponds to the island region, or (ii) a screen printing plate in which an opening pattern corresponds to the island region. Etc. are preferably used.

  The step (B) is the second of the present invention described above, except that a printing ink containing a synthetic resin is used instead of a printing ink containing a material soluble in a solvent, and this is printed on a transparent substrate. Since it can implement similarly to the process (A) in this method, detailed description is abbreviate | omitted here.

  The synthetic resin used for the printing ink may be any resin that is resistant to electroless plating solution and has transparency. For example, at least one selected from the group consisting of an acrylic resin, a polyester resin, a vinyl chloride resin, and a polystyrene resin is preferable. These may be used individually by 1 type and may be used in mixture of 2 or more types.

  The printing ink may contain 5 to 50% by mass, more preferably 10 to 40% by mass of the synthetic resin. If the concentration of the synthetic resin is less than 5% by mass, a plating protective layer having a desired thickness may not be formed, and if it exceeds 50% by mass, the light transmittance of the obtained plating protective layer may be reduced.

  Any solvent can be used for the printing ink as long as it can dissolve the resin and has excellent film formability. Specifically, dichloromethane, tetrahydrofuran, cyclohexanone, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, methyl lactate, ethyl lactate, 2-ethoxyethyl acetate, methyl pyruvate, pyruvate Ethyl, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, cyclohexanone, methyl ethyl ketone, 2-heptanone, 1,4- Dioxane, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, ethylene glycol monoisopropyl ether, toluene, vinegar Ethyl and butyl acetate.

  The resist ink may further contain a transparent filler or a polymer thickener in order to improve the printing finish.

  The printing ink transferred onto the electroless plating catalyst layer is preferably dried at 70 to 120 ° C., more preferably 90 to 110 ° C., for about 5 seconds to 5 minutes.

  Next, in the method of the present invention, the step (C) of forming the electromagnetic wave shielding layer 520 by electroless plating on the electroless plating catalyst layer 590 exposed without forming the plating protective layer 540 is performed. . However, before the step (C), it is preferable to perform a step of performing a reduction treatment on the electroless plating catalyst layer exposed without being covered with the plating protective layer. By the reduction treatment, the noble metal compound contained in the electroless plating catalyst layer can be reduced and metallized, and the catalytic activity can be improved.

  The reduction treatment is not particularly limited as long as it is a method that can reduce and metallize the noble metal compound contained in the electroless plating catalyst layer. Specifically, (i) a liquid phase reduction method in which the transparent substrate on which the electroless plating catalyst layer is formed is treated with a solution containing a reducing agent, and (ii) the electroless plating catalyst layer is formed. A vapor phase reduction method in which a transparent substrate is brought into contact with a reducing gas is preferably used.

  As a method of treating with a solution containing a reducing agent in the liquid phase reduction method, specifically, a method of immersing the transparent substrate on which the electroless plating catalyst layer is formed in a solution containing a reducing agent, A method of spraying a solution containing a reducing agent on the surface of the transparent substrate on which the electroless plating catalyst layer is formed is used.

The solution containing the reducing agent is prepared by dispersing or dissolving a predetermined reducing agent in a solvent such as water. The reducing agent is not particularly limited, but formamide, dimethylformamide, diethylformamide, dimethylacetamide, dimethylacrylamide, sodium borohydride, potassium borohydride, glucose, aminoborane, dimethylamineborane (DMAB), trimethylamineborane (TMAB) ), Hydrazine, diethylamine borane, formaldehyde, glyoxylic acid, imidazole, ascorbic acid, hydroxylamine, hydroxylamine sulfate, hydroxylamine hydrochloride, hypophosphorous acid, hypophosphite such as sodium hypophosphite, hydroxylamine sulfate, Examples thereof include sulfites such as sodium sulfite, hydrosulfite (Na ₂ S ₂ O ₄ : also referred to as sodium dithionite), and the like. If the reducing agent is the same as the reducing agent contained in the electroless plating bath used in the subsequent step, electroless plating can be performed without washing the transparent substrate after the reduction treatment, There is little risk of changing the composition of the electroless plating bath.

  As the reducing agent, aminoborane, dimethylamine borane, sodium hypophosphite, hydroxylamine sulfate, hydrosulfite, and formalin are preferably used because the high reducibility of the noble metal compound can be obtained.

  The content of the reducing agent in the solution containing the reducing agent is preferably 0.01 to 200 g / L, particularly preferably 0.1 to 100 g / L. If the concentration of the reducing agent is too low, it may take a long time to sufficiently perform the reduction treatment, and if the concentration of the reducing agent is too high, the precipitated noble metal may fall off.

  In the liquid phase reduction method, the electroless plating catalyst layer is formed because the precious metal compound contained in the electroless plating catalyst layer is highly reducible as a method of using a solution containing a reducing agent. It is preferable to use a method of immersing the transparent substrate in a solution containing a reducing agent.

  When the transparent substrate is immersed, the temperature of the solution containing the reducing agent is preferably 20 to 90 ° C, particularly 50 to 80 ° C. Further, the immersion time may be at least 1 minute or more, preferably about 1 to 10 minutes.

  On the other hand, when the reduction treatment is performed using the gas phase reduction method, the reducing gas is not particularly limited as long as it is a reducing gas such as hydrogen gas or diborane gas. What is necessary is just to determine suitably the reaction temperature and reaction time at the time of the reduction process using reducing gas according to the kind etc. of reducing gas to be used.

  Next, the electroless plating on the electroless plating catalyst layer reduced in the step (C) can be performed according to a conventional method using an electroless plating bath. That is, it is performed by immersing a plating base material in a plating solution containing a plating metal salt, a chelating agent, a pH adjusting agent, a reducing agent, etc. as a basic composition, or dividing the above-described plating solution into two or more solutions. What is necessary is just to select suitably, such as performing a plating process by an addition system.

  As the plating metal, those described above as the metal constituting the electromagnetic wave shielding layer in the light transmissive electromagnetic wave shielding material of the present invention can be used.

  Electroless plating is well known, and may be carried out at room temperature or under warming according to a conventional method by appropriately selecting and preparing chemicals. As an example of electroless plating, when an electromagnetic shielding layer made of Cu is formed, a water-soluble copper salt such as copper sulfate 1 to 100 g / L, particularly 5 to 50 g / L, a reducing agent such as formaldehyde 0.5 to 0.5 10 g / L, especially 1 to 5 g / L, a solution containing 20 to 100 g / L, particularly 30 to 70 g / L of a complexing agent such as EDTA, and adjusted to pH 12 to 13.5, particularly 12.5 to 13 A method of immersing the transparent substrate on which the electroless plating catalyst layer is formed at 50 to 90 ° C. for 30 seconds to 60 minutes can be employed.

  Further, when performing electroless plating, the substrate to be plated may be rocked and rotated, or the vicinity thereof may be agitated with air.

  In the light-transmitting electromagnetic wave shielding material obtained by the third method of the present invention described above, a plating protective layer is formed in the opening in the electromagnetic wave shielding layer. This plating protective layer is made of synthetic resin such as acrylic resin and is excellent in transparency. Therefore, it can be regarded as an opening in the electromagnetic wave shielding layer of the light transmissive electromagnetic wave shielding material.

(Fourth manufacturing method)
As a method for producing the light-transmitting electromagnetic wave shielding material of the present invention, the following fourth production method can be used in addition to the method described above. Below, the said method is demonstrated, using FIG. In particular;
The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A different electromagnetic shielding layer is a method for producing a light transmissive electromagnetic shielding material formed on a transparent substrate,
A step (A) of forming an electroless plating catalyst layer 690 on a portion corresponding to the sea region of the transparent substrate 610 by printing an electroless plating catalyst ink;
(B) forming an electromagnetic wave shielding layer 620 by electroless plating on the electroless plating catalyst layer 690;
The method including is used.

  The electroless plating catalyst ink used in the step (A) is the same as that used in the third method of the present invention.

  In the step (A), by printing the electroless plating catalyst ink, on the portion corresponding to the sea area composed of the electromagnetic wave shielding layer of the transparent substrate, that is, the sea area composed of the electromagnetic wave shielding layer and the plan view shape; An electroless plating catalyst layer having the same position is formed. In order to form such an electroless plating catalyst layer, for example, (i) a concave plate in which the pattern of the concave portion corresponds to the sea region formed by the electromagnetic wave shielding layer, or (ii) It is preferable to print using a screen printing plate in which the pattern of the opening corresponds to the sea region composed of the electromagnetic wave shielding layer.

(I) In order to produce a concave plate in which the pattern of the concave portion corresponds to the sea region composed of the electromagnetic wave shielding layer, for example, as shown in FIG.
A step (1) of forming a photoresist layer 780 having a pattern in which an opening 781 is formed in a portion corresponding to the sea region formed from the electromagnetic wave shielding layer on the printing plate base material 770, and the opening (2) a step of forming a printing plate having an opening 761 by removing a part of the printing plate substrate 770 exposed at 781 and then removing the photoresist layer 780;
A method including the above can be used.

  In the said process (1), if it is a well-known thing in printing methods, such as the conventional gravure, as a printing plate base material used, it can be used without a restriction | limiting. For example, as shown in FIG. 7, a metal film 760 is formed on a metal substrate 750, such as a metal substrate made of steel, aluminum, or iron, a copper plating film is formed. Can be mentioned. Moreover, the shape of the base material for printing plates should just be well-known shapes, such as flat form or cylinder shape, However, When using gravure printing, it has a cylinder shape generally.

In order to form the photoresist layer having the above-mentioned specific pattern on the printing plate substrate, for example, a method of exposing and developing the photoresist film can be used. When performed using the method, the step (1) includes:
(1-1) a step of forming a photoresist film on the printing substrate; and (1-2) a portion corresponding to the sea region formed by the electromagnetic wave shielding layer of the photoresist film is a non-exposed portion. Then, after exposing the portion corresponding to the island region formed from the opening in the electromagnetic wave shield layer as an exposed portion, the step of removing the photoresist film in the non-exposed portion can be performed.

  In addition, about the said photoresist film, since the thing similar to the photoresist film in the method mentioned above is used as a 1st manufacturing method of a light transmissive electromagnetic wave shielding material, detailed description is abbreviate | omitted here.

  The specific pattern described above in the photoresist layer is preferably formed based on image data obtained by FM screening. By using the FM screen in this manner, the electromagnetic wave shielding layer having the sea-island structure shown in FIG. 1B can be formed easily and with high accuracy. Therefore, the exposure of the photoresist film in the step (1-2) is preferably performed based on image data including an FM screen obtained by FM screening, for example. Also for the exposure and development of the photoresist film, since the same method as the above-mentioned step (B) is used as the first manufacturing method of the light-transmitting electromagnetic wave shielding material, detailed description is omitted here.

  The shape of the dots constituting the FM screen may be any shape such as a polygon such as a triangle and a quadrangle, a circle, and an ellipse. Of these, a quadrangle, particularly a square is preferable.

  The dots constituting the FM screen are preferably quadrangles having a side length of 30 to 2 μm, particularly 30 to 15 μm. In the FM screen, the dot portion does not transmit light, and the portion other than the dot transmits light. Therefore, a dot portion, preferably an aggregate portion of a plurality of dots in the FM screen forms an opening in the photoresist film. Therefore, by making the shape of the dots constituting the FM screen as described above, a photoresist layer having an opening at a site corresponding to the sea region formed from the electromagnetic wave shielding layer can be formed.

  Further, the total area of dots with respect to the total area of the FM screen is preferably 60 to 20%, particularly preferably 50 to 40%. By setting the total area to 20% or more, an electromagnetic shielding layer having a sea-island structure in which a plurality of island regions are connected can be easily formed. By setting the total area to 60% or less, a high aperture ratio of the electromagnetic shielding layer is achieved. Can be secured.

  Next, in the step (2), first, a part of the printing plate substrate exposed at the opening in the photoresist layer can be etched using a conventionally known method. For example, it can be performed using an etchant such as iron chloride, copper chloride, ammonia sulfate, ammonia alkali, chromium sulfate, nitric acid, or the like.

  In the step (2), after the etching, the patterned photoresist layer can be removed using, for example, an aqueous sodium hydroxide solution.

  By the step (2), a concave plate having a concave pattern corresponding to the sea region composed of the electromagnetic wave shielding layer can be formed. The opening in the concave plate functions as an ink containing cell. In the method, it is preferable that the shape of the concave plate patterned in this way has a structure similar to the sea-island structure as shown in FIG. Further, the width of the island region formed of the photoresist layer and the opening of the photoresist layer, and the aperture ratio in the photoresist layer may be determined so that a desired electromagnetic wave shielding layer can be obtained.

  In order to form an electroless plating catalyst layer on a portion corresponding to the sea area of a transparent substrate by printing an electroless plating catalyst ink on the transparent substrate using the intaglio plate produced as described above, What is necessary is just to carry out similarly to printing methods, such as a well-known gravure printing method. For example, after applying the electroless plating catalyst ink to the intaglio, the printing ink accommodated in the concave portion of the intaglio is transferred onto the transparent substrate by bringing it into contact with the transparent substrate.

  In order to produce a screen printing plate in which the pattern of the opening used in step (A) corresponds to the island region formed from the opening in the electromagnetic wave shielding layer, an electromagnetic wave is formed on the mesh substrate. A method of forming a photoresist layer having a pattern having an opening in which a mesh base material is exposed in a portion corresponding to the sea region formed from the shield layer is used.

  In order to form a photoresist layer having such a specific pattern, the same layer as the etching protection layer (ii) in the concave plate described above is used.

  The mesh base material is not particularly limited as long as it is a conventionally known material used in screen printing. There are resin fibers such as silk, nylon, and polyester, and a stainless mesh, but when printing accuracy is required, a stainless mesh with little expansion and contraction and good dimensional accuracy is used. For example, a stainless steel wire having a wire diameter of 14 μm expressed as SS380-14 and having a density of 380 per 25.4 mm (1 inch) and a plain weave mesh is used.

  In order to form a plating protective layer on a portion corresponding to the island region of the transparent substrate by printing the electroless plating catalyst ink on the transparent substrate using the screen printing plate prepared as described above, conventionally, What is necessary is just to carry out similarly to the well-known screen printing method.

  Moreover, as a printing method of the electroless plating catalyst ink in the step (A), in addition to the method using the concave plate or the screen printing plate described above, the electroless plating catalyst ink is used for the concave plate or the screen printing described above. Similarly to the plate, it can be performed by printing like an image based on image data obtained by FM screening. As the printing method, for example, an inkjet method can be used.

  In the step (A), the printing ink printed on the transparent substrate is preferably dried. The drying may be performed by leaving at room temperature, or may be performed by heating at 90 to 130 ° C. for 2 to 10 seconds. Thereby, the plating protective layer formed using the printing ink on the transparent substrate is obtained. The thickness of the plating protective layer may be about 0.1 to 5 μm.

  Next, in the method of the present invention, a step of forming an electromagnetic wave shielding layer by performing electroless plating on the electroless plating catalyst layer produced as described above is performed. Moreover, you may implement the process of performing a reduction process to the electroless-plating catalyst layer before the said process. In addition, since the same method as described in the third method of the present invention is used for the electroless plating step and the reduction treatment step, detailed description is omitted here.

  In the first to fourth manufacturing methods of the present invention described above, when it is desired to improve the electromagnetic wave shielding effect by making the electromagnetic wave shielding layer have a lower resistance value, a metal plating layer is formed on the electromagnetic wave shielding layer formed on the transparent substrate. It is preferable to carry out the forming step.

  The metal plating layer can be formed by a known electrolytic plating method or electroless plating method. Generally, copper, copper alloy, nickel, silver, gold, zinc or tin can be used as the metal used for plating. These can be used alone or as two or more kinds of alloys. You may do it. Copper, copper alloy, silver, or nickel is preferable, and copper or copper alloy is particularly preferably used from the viewpoint of economy and conductivity.

  Further, the electromagnetic wave shielding layer may be provided with antiglare performance. Therefore, in the method of the present invention, the blackening treatment layer may be provided on the surface of the electromagnetic wave shielding layer and / or the metal plating layer by the step of blackening the electromagnetic wave shielding layer and / or the metal plating layer. . For example, it can be performed by oxidation treatment of the electromagnetic wave shielding layer and / or metal plating layer, sulfurization treatment, black plating of chromium alloy or the like, or application of black or dark ink. Among these, as the blackening treatment, oxidation treatment and sulfurization treatment are preferable.

  When the oxidation treatment is performed as the blackening treatment, the blackening treatment liquid is generally a mixed aqueous solution of hypochlorite and sodium hydroxide, a mixed aqueous solution of chlorite and sodium hydroxide, peroxodisulfuric acid, It is possible to use a mixed aqueous solution of sodium hydroxide, etc. Especially from the economical point of view, a mixed aqueous solution of hypochlorite and sodium hydroxide or a mixed aqueous solution of chlorite and sodium hydroxide is used. It is preferable to do.

  In the case of performing sulfurization treatment as the blackening treatment, it is generally possible to use an aqueous solution such as potassium sulfide, barium sulfide and ammonium sulfide as the blackening treatment liquid, preferably potassium sulfide and ammonium sulfide. In particular, ammonium sulfide is preferably used because it can be used at a low temperature.

  The thickness of the blackening treatment layer is not particularly limited, but is 0.01 to 1 μm, preferably 0.01 to 0.5 μm. If the thickness is less than 0.01 μm, the antiglare effect of light may not be sufficient, and if it exceeds 1 μm, the apparent aperture ratio when viewed from the perspective may be reduced.

(Fifth manufacturing method)
As a manufacturing method of the light-transmitting electromagnetic wave shielding material of the present invention, the following fifth manufacturing method can be used in addition to the above-described method. Specifically, the shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in a sea region in the sea-island structure, and openings are formed in a number of island regions, and the island region A method for producing a light-transmitting electromagnetic wave shielding material formed on a transparent substrate, electromagnetic wave shielding layers having different shapes from each other,
Forming an electromagnetic wave shielding layer by printing a conductive ink containing conductive particles and a binder resin on a portion corresponding to the sea region of the transparent substrate;
It is a method including.

  The conductive ink includes conductive particles and a binder resin. Examples of the conductive particles include aluminum, nickel, indium, chromium, gold, vanadium, tin, cadmium, silver, platinum, copper, titanium, cobalt, lead, and other metals and alloys; or ITO, indium oxide, tin oxide, and oxide. Conductivity such as zinc, indium oxide-tin oxide (ITO, so-called indium-doped tin oxide), tin oxide-antimony oxide (ATO, so-called antimony-doped tin oxide), zinc oxide-aluminum oxide (ZAO; so-called aluminum-doped zinc oxide) An oxide etc. can be mentioned. These may be used alone or in combination of two or more.

  Especially, as said electroconductive particle, silver, copper, gold | metal | money, nickel, indium, and tin are mentioned preferably. With these conductive particles, the conductivity of the resulting mesh-like conductive layer can be improved by contact with a strong acid as described later.

  The average particle diameter of the conductive particles is preferably 10 nm to 10 μm, particularly preferably 10 nm to 5 μm. Thereby, as will be described later, the conductivity can be improved by contact with a strong acid, and a conductive layer having excellent conductivity can be formed.

  The content of the conductive particles in the conductive ink is preferably 400 to 1000 parts by mass, particularly 400 to 800 parts by mass with respect to 100 parts by mass of the binder resin. Thereby, the conductive layer excellent in the contact property of electroconductive particles can be formed.

  Examples of the binder resin used in the conductive ink include acrylic resin, polyester resin, epoxy resin, urethane resin, phenol resin, maleic acid resin, melamine resin, urea resin, polyimide resin, and silicon-containing resin. Furthermore, it is preferable that it is a thermosetting resin among these resins.

  The conductive ink may further contain a solvent in order to adjust to an appropriate viscosity. Examples of the solvent include alcohols such as hexanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, stearyl alcohol, seryl alcohol, cyclohexanol, terpineol; ethylene glycol monobutyl ether (butyl cellosolve), ethylene Examples thereof include alkyl ethers such as glycol monophenyl ether, diethylene glycol, diethylene glycol monobutyl ether (butyl carbitol), cellosolve acetate, butyl cellosolve acetate, carbitol acetate, and butyl carbitol acetate.

  The conductive ink may further contain a black colorant. Thereby, with the improvement of a printing precision, the glare-proof effect at the time of seeing from the transparent substrate side can be provided in the light transmissive electromagnetic wave shielding material obtained.

  Preferred examples of the black colorant include carbon black, titanium black, black iron oxide, graphite, and activated carbon. These may be used individually by 1 type and may be used in mixture of 2 or more types. Of these, carbon black is preferable. Examples of carbon black include acetylene black, channel black, and furnace black. The average particle size of carbon black is preferably 0.1 to 1,000 nm, particularly preferably 5 to 500 nm.

  The content of the black colorant in the conductive ink is preferably 0.1 to 10 parts by mass, particularly 1 to 5 parts by mass with respect to 100 parts by mass of the binder resin.

  The conductive ink may further contain a conventionally known auxiliary agent such as a dispersant such as a surfactant, a plasticizer, an antifoaming agent, and a curing agent.

  In the method of the present invention, in order to print the conductive ink on the portion of the transparent substrate corresponding to the sea region composed of the electromagnetic wave shielding layer, for example, the conductive ink is used, Printing is preferably performed using a corresponding intaglio plate or (ii) a screen printing plate in which the pattern of openings corresponds to the sea area. Since these methods can be carried out in the same manner as the fourth method of the present invention except that conductive ink is used in place of the electroless plating catalyst ink, detailed description thereof is omitted here.

  In addition to the method using the concave plate or screen printing plate described above, the conductive ink can be obtained by FM screening in the same manner as the concave plate or screen printing plate described above. It can also be performed by printing in an image-like manner based on the image data. As the printing method, for example, an inkjet method can be used.

  The conductive ink printed on the transparent substrate is usually preferably cured by drying at room temperature to 250 ° C.

  Hereinafter, the present invention will be described with reference to examples. The present invention is not limited by the following examples.

(Example 1)
A biaxially stretched polyethylene terephthalate film (PET film) (thickness: 100 μm, Lumirror manufactured by Toray Industries, Inc.) was prepared as a transparent substrate. After forming a copper film (thickness: 3.0 μm) on one side of this film by vacuum evaporation under a vacuum of 1.3 × 10 ⁻³ Pa at room temperature, a photosensitive resist ( By applying PMER-N HC600Y manufactured by Tokyo Ohka Kogyo Co., Ltd. with a bar coater and drying at 80 ° C. for 10 minutes, a laminate of PET film / copper film / photosensitive resist film was obtained.

Next, FM screening is performed by the FM screening program to obtain image data consisting of an FM screen (dot shape: square with a side length of 20 μm, total area of dots 45% of the total area of the FM screen). Based on this, the photosensitive resist film was exposed to an ultraviolet ray of 60 mJ / cm ² and alkali-developed, and then washed and dried to pattern the photosensitive resist film. As a result, a photoresist layer having a sea-island structure in which a photoresist layer was formed in the sea region, openings were formed in a number of island regions, and the shapes of the island regions were different from each other was obtained.

  Next, the copper film exposed in the opening was etched with a cupric chloride solution, and the photoresist layer was peeled off with a strong alkaline solution. Thereby, the electromagnetic wave shielding layer (opening ratio 55%) which shows the sea-island structure which consists of copper as shown in FIG.1 (B) was formed on PET film, and the light-transmitting electromagnetic wave shielding material was obtained. The electromagnetic shielding layer (average width 40 μm, thickness 3.0 μm) was formed in the sea region of the sea-island structure, and openings (average width 60 μm) were formed in many island regions.

(Example 2)
By applying a photosensitive resist (PMER-N HC600Y manufactured by Tokyo Ohka Kogyo Co., Ltd.) with a bar coater on the surface of a copper substrate (thickness 100 μm) as a printing plate base material, and drying at 80 ° C. for 10 minutes, And a laminate of the photosensitive resist film was obtained.

Next, FM screening is performed by the FM screening program to obtain image data consisting of an FM screen (dot shape: square with a side length of 20 μm, total area of dots 45% of the total area of the FM screen). Based on this, the photosensitive resist film was exposed to an ultraviolet ray of 60 mJ / cm ² and alkali-developed, and then washed and dried to pattern the photosensitive resist film. As a result, a photoresist layer having a sea-island structure in which a photoresist layer was formed in the sea region, openings were formed in a number of island regions, and the shapes of the island regions were different from each other was obtained.

  Next, the copper substrate exposed in the opening was etched to a depth of 5 μm with a cupric chloride solution, and the resist film was peeled off with a strong alkali solution. As a result, a printing plate in which an ink containing cell was formed in the etched portion was produced.

  Next, on one side of a biaxially stretched polyethylene terephthalate film (PET film) (thickness 100 μm, Lumirror manufactured by Toray Industries, Inc.), a two-component curable aqueous adhesive (trade name, ADW-615, manufactured by Toyo Motor Co., Ltd.) / CAT-EP5) was applied by gravure coating to form an adhesive layer (thickness 0.5 μm).

  A polyvinyl alcohol aqueous solution with a solid content of 20% by mass is applied to the previously prepared printing plate, and after the excess polyvinyl alcohol aqueous solution adhering to the printing plate surface is scraped off by a doctor blade, the polyvinyl alcohol aqueous solution of the printing plate is applied. The adhesive layer formed on the PET film and the adhesive layer formed on the PET film are overlapped and adhered with a roller, and then the printing plate is peeled off to remove the polyvinyl alcohol aqueous solution contained in the ink containing cell. Transcribed above. Then, the plating protective layer was formed by drying the polyvinyl alcohol aqueous solution on an adhesive bond layer at 100 degreeC for 3 minutes.

Next, after forming a copper film (thickness 0.3 μm) on the adhesive layer on which the plating protective layer has been formed by vacuum deposition under a vacuum of 1.3 × 10 ⁻³ Pa at room temperature. The surface was rubbed with a sponge while immersed in water at 25 ° C., the plating protective layer was dissolved and removed, rinsed with water, and dried at 100 ° C. for 3 minutes. Thereby, the electromagnetic wave shielding layer (opening ratio 65%) which shows the sea island structure which consists of copper as shown in FIG.1 (B) was formed on PET film, and the light-transmitting electromagnetic wave shielding material was obtained. The electromagnetic shielding layer (average width 37 μm, thickness 3.0 μm) was formed in the sea region of the sea-island structure, and openings (average width 63 μm) were formed in many island regions.

Next, on the electromagnetic wave shielding layer prepared above, as the following plating solution and plating conditions,
A metal plating layer made of copper was formed by electrolytic copper plating. The metal plating layer had a thickness of 3.0 μm, a line width of 39 μm, and an aperture ratio of 60%.

Plating solution Copper sulfate: 200-250 g / L
Metallic copper: 50-62 g / L
Sulfuric acid: 35-75 g / L
Sulfuric acid / copper copper: about 1/1
Chlorine: 20-40mg / L
Electroplating conditions Electrolyte temperature: 30 ° C
Plating solution temperature: 30 ° C
Current density: 5 A / dm ²
Processing time: 30 minutes

(Comparative Example 1)
A mixture of polyvinyl alcohol resin (molecular weight 3000) and barium sulfate (mass ratio polyvinyl alcohol resin: barium sulfate = 2: 1) was dissolved in a mixed solution of water and methanol (mass ratio water: methanol = 1: 4), A polyvinyl alcohol solution having a solid content of 20 wt% was prepared. Using this solution as an ink, square dots were printed by gravure printing on a PET film (thickness 100 μm, Lumirror manufactured by Toray Industries, Inc.). After drying this, copper was vacuum-deposited to obtain a copper layer having a thickness of 0.3 μm. Next, the dot portion was dissolved and removed with water at 25 ° C., washed with water and dried to obtain a light transmissive electromagnetic wave shielding material in which an electromagnetic wave shielding layer composed of a mesh copper layer was formed on the PET film.

  Each of the dots had a square shape with a size of 200 μm per side, the interval between the dots was 20 μm, the dot array was a square lattice, and the printed thickness of the dots was about 2 μm after drying. Reflecting this accurately, the mesh-like electromagnetic shielding layer has a square lattice shape corresponding to the negative pattern of dots, the line width is 20 μm, the pitch between the lattices is 200 μm, and the aperture ratio is 80% (area ratio). there were.

  Next, an electrolytic copper plating process was performed on the electromagnetic wave shielding layer produced above in the same manner as in Example 2 to form a metal plating layer made of copper. The metal plating layer had a thickness of 3.0 μm, a line width of 22 μm, and an aperture ratio of 78%.

(Evaluation)
1. Moire generation Each light-transmitting electromagnetic wave shielding material produced above is installed on the front surface of a PDP device having a pixel pitch of 1.26 mm (RGB each cell 0.42 mm), and the state of moire generation between the pixel and the electromagnetic wave shielding layer is observed. It was observed visually. In the light-transmitting electromagnetic wave shielding material produced in Comparative Example 1, moire fringes with a period of 2 to 20 mm were generated in the regions of bias angles of 0 ° to 10 ° and 30 ° to 90 °, and the display quality was poor. . On the other hand, in the light-transmitting electromagnetic wave shielding materials of Examples 1 and 2, generation of moire could not be confirmed at any bias angle.

2. Electromagnetic wave shielding property The electromagnetic wave shielding property of each light-transmitting electromagnetic wave shielding material produced above is measured using an Anritsu EMI shield measuring device (MA8602B) in accordance with the KEC method (Kansai Electronics Industry Promotion Center). It evaluated by measuring the attenuation factor (dB) of electromagnetic waves in the range of 50-500 MHz. The sample size was 90 mm × 110 mm. The results are shown in Table 1. In Table 1, those with an electromagnetic wave attenuation rate of 50 dB or more are indicated as “◯”, and those with less than 10 dB are indicated as “x”.

3. Light transmittance Using a fully automatic direct reading haze computer HGM-2DP (manufactured by Suga Test Instruments Co., Ltd.), the total light transmittance in the thickness direction of each of the light transmissive electromagnetic wave shielding materials produced above was measured. The said measurement was implemented in three places in the light transmissive electromagnetic wave shielding material, The light transmittance was evaluated by making the average value into the total light transmittance of the light transmissive electromagnetic wave shielding material. The results are shown in Table 1.

FIG. 1A is a cross-sectional view of the light transmissive electromagnetic wave shielding material of the present invention, and FIG. 1B is a schematic top view of a concavo-convex shape of a sea-island structure possessed by the electromagnetic wave shielding layer of the light transmissive electromagnetic wave shielding material. is there. It is explanatory drawing of each process in the 1st manufacturing method of the transparent electromagnetic wave shielding material of this invention. It is explanatory drawing of each process in the 2nd manufacturing method of the transparent electromagnetic wave shielding material of this invention. It is explanatory drawing of each process in the preparation method of the concave plate used suitably for the 2nd manufacturing method of the light-transmitting electromagnetic wave shielding material of this invention. It is explanatory drawing of each process in the 3rd manufacturing method of the transparent electromagnetic wave shielding material of this invention. It is explanatory drawing of each process in the 4th manufacturing method of the transparent electromagnetic wave shielding material of this invention. It is explanatory drawing of each process in the preparation method of the concave plate used suitably for the 4th manufacturing method of the light-transmitting electromagnetic wave shielding material of this invention.

Explanation of symbols

110, 210, 310, 510, 610 transparent substrate,
120, 220, 320, 520, 620 Electromagnetic wave shielding layer,
121, 221 and 321 openings,
222 metal film,
322 conductive material layer,
340 mask layer,
540 plating protective layer,
450, 750 metal substrate,
460, 760 metal film,
461 and 761 ink storage cells,
470, 770 printing substrate,
480, 780 photoresist layer,
481, 781 recess,
590, 690 Electroless plating catalyst layer.

Claims (34)

A light transmissive electromagnetic shielding material having a transparent substrate and an electromagnetic shielding layer provided on the transparent substrate,
The electromagnetic shielding layer has a sea-island structure in plan view, and the electromagnetic shielding layer is formed in a sea region in the sea-island structure, and a plurality of island regions have openings, and the island region The light-transmitting electromagnetic wave shielding material characterized by having different shapes.   The light-transmitting electromagnetic wave shielding material according to claim 1, wherein the island region has an irregularly bent and / or branched shape.   The light transmitting electromagnetic wave shielding material according to claim 1, wherein an average width of the island region is 5 to 200 μm.   4. The light-transmitting electromagnetic wave shielding material according to claim 1, wherein an average width of the sea region is 5 to 200 μm.   The light-transmitting electromagnetic wave shielding material according to any one of claims 1 to 4, wherein the sea region has a thickness of 0.1 to 20 µm.   The light-transmitting electromagnetic wave shielding material according to claim 1, wherein an opening ratio of the electromagnetic wave shielding layer is 40 to 95%.   The light-transmitting electromagnetic wave shielding material according to claim 1, wherein the electromagnetic wave shielding layer is produced based on image data obtained by FM screening.   The light-transmitting electromagnetic wave shielding material according to claim 1, wherein the electromagnetic wave shielding layer is made of a metal including at least one selected from the group consisting of silver, copper, and aluminum.   An optical filter for display, wherein the light-transmitting electromagnetic wave shielding material according to claim 1 is used.   A display comprising the optical filter for display according to claim 9 bonded to a surface of an image display glass plate. The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A different electromagnetic shielding layer is a method for producing a light transmissive electromagnetic shielding material formed on a transparent substrate,
Forming a metal film on the transparent substrate, and then forming an etching protective layer on the metal film corresponding to the sea region (A),
A step (B) of etching a metal film exposed without forming the etching protective layer, and a step (C) of removing the etching protective layer,
A method for producing a light-transmitting electromagnetic wave shielding material, comprising:   The etching protective layer is produced by producing a photoresist film on the metal film and then exposing and developing the photoresist film imagewise based on image data obtained by FM screening. The method for producing a light-transmitting electromagnetic wave shielding material according to claim 11.   The light-transmitting electromagnetic wave shielding material according to claim 12, wherein the dots constituting the image data are squares each having a side length of 2 to 30 μm.   14. The light-transmitting electromagnetic wave shielding material according to claim 12, wherein the total area of dots with respect to the total area of the image data is 20 to 60%. The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A different electromagnetic shielding layer is a method for producing a light transmissive electromagnetic shielding material formed on a transparent substrate,
A step (A) of forming a mask layer on a portion corresponding to the island region of the transparent substrate by printing a printing ink containing a material soluble in a solvent;
Forming a conductive material layer containing a conductive material insoluble in the solvent on the transparent substrate having the mask layer (B);
(C) forming the electromagnetic wave shielding layer by removing the mask layer and the conductive material layer on the mask layer with the solvent;
A method for producing a light-transmitting electromagnetic wave shielding material, comprising:   The printing in the step (A) is performed using a concave plate in which a concave pattern corresponds to the island region, or a screen printing plate in which an opening pattern corresponds to the island region. The manufacturing method of the light transmissive electromagnetic wave shielding material of description.   The method for producing a light-transmitting electromagnetic wave shielding material according to claim 16, wherein the pattern is formed based on image data obtained by FM screening.   The light transmissive electromagnetic wave shielding material according to claim 17, wherein the dots constituting the image data are squares each having a side length of 2 to 30 μm.   19. The light-transmitting electromagnetic wave shielding material according to claim 17, wherein a total area of dots with respect to the total area of the image data is 20 to 60%. The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A method for producing a light-transmitting electromagnetic wave shielding material in which different electromagnetic wave shielding layers are formed on a transparent substrate via an electroless plating catalyst layer,
A step (A) of producing an electroless plating catalyst layer on a transparent substrate;
A step (B) of forming a plating protective layer on a portion corresponding to the island region of the electroless plating catalyst layer by printing a printing ink containing a synthetic resin;
A step (C) of forming an electromagnetic wave shielding layer by electroless plating on the electroless plating catalyst layer exposed without forming the plating protective layer;
A method for producing a light-transmitting electromagnetic wave shielding material, comprising:   21. The printing in the step (B) is performed using a concave plate in which a concave pattern corresponds to the island region, or a screen printing plate in which an opening pattern corresponds to the island region. The manufacturing method of the light transmissive electromagnetic wave shielding material of description.   The method for producing a light-transmitting electromagnetic wave shielding material according to claim 21, wherein the pattern is formed based on image data obtained by FM screening.   23. The light transmissive electromagnetic wave shielding material according to claim 22, wherein the dots constituting the image data are squares each having a side length of 2 to 30 [mu] m.   The light-transmitting electromagnetic wave shielding material according to any one of claims 22 and 23, wherein a total area of dots with respect to a total area of the image data is 20 to 60%. The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A different electromagnetic shielding layer is a method for producing a light transmissive electromagnetic shielding material formed on a transparent substrate,
A step (A) of forming an electroless plating catalyst layer on a portion of the transparent substrate corresponding to the sea region by printing an electroless plating catalyst ink;
Step (B) of forming an electromagnetic wave shielding layer by electroless plating on the electroless plating catalyst layer;
A method for producing a light-transmitting electromagnetic wave shielding material, comprising:   The printing in the step (A) is performed using a concave plate in which a concave pattern corresponds to the sea region, or a screen printing plate in which an opening pattern corresponds to the sea region. The manufacturing method of the light transmissive electromagnetic wave shielding material of description.   27. The method for producing a light-transmitting electromagnetic wave shielding material according to claim 26, wherein the pattern is formed based on image data obtained by FM screening.   28. The light transmissive electromagnetic wave shielding material according to claim 27, wherein the dots constituting the image data are squares having a side length of 30 to 2 [mu] m.   30. The light transmissive electromagnetic wave shielding material according to claim 27, wherein a total area of dots with respect to a total area of the image data is 60 to 20%. The shape in plan view shows a sea-island structure, and the electromagnetic shielding layer is formed in the sea region in the sea-island structure, and openings are formed in a number of island regions, and the shape of the island regions is mutually A method for producing a light-transmitting electromagnetic wave shielding material, wherein different electromagnetic wave shielding layers are formed on a transparent substrate,
Forming an electromagnetic wave shielding layer by printing a conductive ink containing conductive particles and a binder resin on a portion corresponding to the sea region of the transparent substrate;
A method for producing a light-transmitting electromagnetic wave shielding material, comprising:   The light according to claim 32, wherein the printing in the step is performed using a concave plate in which a concave pattern corresponds to the sea area, or a screen printing plate in which an opening pattern corresponds to the sea area. A method for producing a transparent electromagnetic shielding material.   32. The method for producing a light-transmitting electromagnetic wave shielding material according to claim 31, wherein the pattern is formed based on image data obtained by FM screening.   33. The light transmissive electromagnetic wave shielding material according to claim 32, wherein the dots constituting the image data are squares having a side length of 30 to 2 [mu] m.   34. The light transmissive electromagnetic wave shielding material according to claim 32, wherein a total area of dots with respect to a total area of the image data is 60 to 20%.

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