JP2008283029A - Manufacturing method of electromagnetic wave shielding film, and electromagnetic wave shielding film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an electromagnetic wave shielding film capable of manufacturing an electromagnetic wave shielding film inexpensively with high productivity using a silver salt system, the film having transparency higher than that in a photolithography system even with the same resistance. <P>SOLUTION: In a manufacturing method of an electromagnetic wave shielding film, a coating solution containing metal salt particulates is uniformly applied and dried on a continuously running supporter. A coated layer is subsequently and continuously subjected to mesh pattern exposure using a mask and is thereafter subjected to development processing to form a metal mesh pattern on a support. Then, physical development processing and/or plating processing are performed to impart conductivity to a metal mesh pattern so that an electromagnetic shielding function becomes available. In the method, mesh pattern exposure onto the coated layer on the conveyed substrate is performed such that adjacent mesh patterns are partly overlapped. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention performs exposure, development, physical development and / or plating treatment on a layer in which a coating solution containing metal salt fine particles is uniformly applied and formed on a continuously running support, thereby producing a metal portion, light transmission The present invention relates to a method for producing an electromagnetic wave shielding film in which a conductive metal mesh pattern consisting of parts is continuously formed on a support, and also relates to an electromagnetic wave shielding film produced by the production method.

  In recent years, with the increasing use of various electrical equipment and electronic application equipment, Electromagnetic Interference (EMI) has increased rapidly, and in electronic and electrical equipment, the intensity of electromagnetic wave emission can be kept within standards or regulations. It is requested.

  For example, there are electromagnetic wave shielding materials used for the front surface of a display such as CRT (cathode ray tube), PDP (plasma display panel), liquid crystal, EL (electroluminescence).

  In particular, since PDP generates a large amount of electromagnetic waves and requires strong electromagnetic shielding ability as compared with CRT or the like, extremely high conductivity is required for a light-transmitting electromagnetic shielding material for PDP.

  The translucent electromagnetic wave shielding material is produced by forming a conductive mesh pattern on a support by any method, or forming a metal ultra-thin film on the entire surface of the support.

  Various materials and methods have been proposed for the production of conductive mesh patterns. For example, a method of forming a metal thin film mesh on a transparent substrate by etching using a metal thin film photolithography method has been proposed (for example, Patent Document 1).

  In addition to this, a method of forming a thin film mesh pattern of metallic silver using a silver salt photosensitive material is known. The silver salt fine particle-containing photosensitive layer is exposed, developed, and after forming a metallic silver portion and a light transmitting portion, the conductive silver particles are supported on the metallic silver portion by physical development and / or plating treatment, A conductive metal mesh pattern that simultaneously satisfies high conductivity and translucency can be easily obtained as an electromagnetic wave shielding film (for example, Patent Document 2).

  However, the above-described method using photolithography (Patent Document 1) requires a large number of steps and man-hours, so that the production yield is low, the apparatus cost is high, and the cost is extremely increased.

Further, in the method using the silver salt fine particle-containing photosensitive material of Patent Document 2, since the mesh pattern exposure of the silver salt fine particle-containing photosensitive layer is performed digitally, the apparatus cost becomes very expensive, resulting in a low manufacturing cost. It will be up.
JP 2003-46293 A JP 2004-221564 A

  Accordingly, an object of the present invention is to provide a method for producing an electromagnetic wave shielding film that can produce an electromagnetic wave shielding film that uses a silver salt method, is low in cost, has high productivity, and has a high transmittance even with the same resistance value as the photolithography method Is to provide.

  The above object of the present invention is achieved by the following means.

  1. A coating solution containing metal salt fine particles is uniformly applied on a continuously running support, dried, and then subjected to mesh pattern exposure sequentially and continuously using a mask on the coating layer, followed by development. A metal mesh pattern is formed on a support by treatment, and then a physical development treatment and / or a plating treatment is performed to impart conductivity to the metal mesh pattern to provide an electromagnetic shielding film. In the method, a method for producing an electromagnetic wave shielding film, wherein the mesh pattern exposure to the coating layer on the carrier to be conveyed is exposed so that adjacent mesh patterns partially overlap each other.

  2. The overlap when the adjacent mesh patterns are exposed so that they partially overlap each other is in the range of 0.2 to 3% of the longitudinal length of the support of the mesh pattern exposed at once by the mask. The manufacturing method of the electromagnetic wave shielding film of said 1 said.

  3. 3. The method for producing an electromagnetic wave shielding film according to 1 or 2 above, wherein the mask has a light transmission part which does not form a mesh as an outer frame of the mesh pattern.

  4). 3. The method for producing an electromagnetic wave shielding film according to 1 or 2, wherein the mask does not form a mesh as an outer frame of the mesh pattern and does not have a light transmission part.

  5. The method for producing an electromagnetic wave shielding film according to any one of 1 to 4, wherein the development treatment, the physical development treatment and / or the plating treatment are treated with a roll-to-roll.

  6). 6. The method for producing an electromagnetic wave shielding film according to any one of 1 to 5, wherein the plating treatment includes an electroless plating treatment, followed by an electrolytic plating treatment.

  7. The production of the electromagnetic wave shielding film according to any one of 1 to 5 above, wherein the plating treatment is performed by first performing electrolytic plating at a low current value and then performing electrolytic plating at a high current value. Method.

  8). 8. The method for producing an electromagnetic wave shielding film according to any one of 1 to 7, wherein the metal salt fine particles are metal halide fine particles.

9. 9. The method for producing an electromagnetic wave shielding film as described in any one of 1 to 8 above, wherein the coating amount of the metal component of the metal halide fine particles is 0.3 to 1 g / m ² by extrusion extrusion coating under reduced pressure.

  10. 10. An electromagnetic wave shielding film produced by the method for producing an electromagnetic wave shielding film according to any one of 1 to 9 above.

  According to the present invention, it was possible to provide a method for producing an electromagnetic wave shielding film at low cost and high productivity using a silver salt method.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

  Production of an electromagnetic shielding material against electromagnetic interference (EMI) by a silver salt method is performed by applying a silver salt on a base film, pattern exposure to a coating layer, developing a mesh, physical development, and / or plating. This is performed by a process of imparting conductivity.

  In production, it is desired that a conductive film is continuously formed so that the production process can be continuously assembled. If the digital exposure technique is used, a conductive portion can be continuously formed in this way, but the digital exposure machine has a high apparatus cost and a large equipment investment burden.

  The present invention is a technique for continuously forming a conductive film by pattern exposure using a mask, and the apparatus cost is low.

  In the production of electromagnetic shielding materials, if a conductive film cannot be formed continuously, there are problems of lowering the productivity of the plating process and lowering the yield of the plating (failure occurrence). By manufacturing a certain film, the cost can be reduced. This is particularly noticeable when electrolytic plating is performed.

  Therefore, the present invention uniformly applies a coating solution containing metal salt fine particles, specifically, a coating solution containing silver salt fine particles, to a continuously running support, and then applies the silver salt fine particle coating. A mask is used for the layer, and a mesh pattern exposure is sequentially performed and a development process is performed to continuously form a metal mesh pattern on the support, and then a physical development process and / or a plating process is performed on the metal mesh. When an electromagnetic wave shielding film is produced by applying a catching treatment to a metal mesh to produce an electromagnetic wave shielding film, the mesh pattern exposure by the mask on the coating layer on the support to be conveyed is one portion where the adjacent pattern exposure is performed. It is a manufacturing method of the electromagnetic wave shielding film characterized by performing so that it may overlap.

  For example, a roll film of polyethylene terephthalate, polycarbonate, triacetylcellulose, or the like is used as the support for forming a conductive metal part continuously by pattern exposure using a mask, but the invention is not limited thereto.

  For the formation of the silver salt fine particle-containing photosensitive layer on the support, the technique of a silver salt photosensitive material can be used. After coating and drying, a metal mesh pattern is formed on the silver salt fine particle-containing photosensitive layer formed on the support by successively performing exposure and development. In order to impart a strong electromagnetic wave shielding ability thereto, physical development and / or plating treatment is further performed. Metallic silver formed by physical development and / or development of the silver salt fine particle-containing photosensitive layer by plating treatment is further reinforced by metal plating, and the line width is increased to improve conductivity.

  In the present invention, the silver salt fine particle-containing photosensitive layer is developed and then subjected to a physical development process and / or a plating process. The plating process preferably comprises an electroless plating process, followed by an electrolytic plating process. In order to impart sufficient electromagnetic wave shielding ability to the metal mesh made of metallic silver, it is preferable to perform electrolytic plating.

  In the present invention, the fact that the conductive film is continuously formed greatly improves the efficiency of the electrolytic plating process.

  Unlike electroless plating, electrolytic plating applies a potential to the material to be plated and deposits metal here, so the conductive layer that constitutes the electromagnetic shielding material is continuously used to increase the productivity of the electrolytic plating process. Preferably it is formed.

  Hereinafter, a method of forming a continuous conductive layer by continuously exposing a silver salt fine particle-containing photosensitive layer on a support using a mask according to the present invention will be described.

  FIG. 1 conceptually shows an exposure mask M and a mesh pattern P formed by the mask. For example, in the case of a 42-inch monitor, mesh pattern exposure having a size of about 600 to 1000 mm and an area size that can cover the entire monitor surface can be performed.

  FIG. 1B schematically shows a mask to be used, and FIG. 1A shows an example of a mesh pattern obtained by mask exposure.

  The mesh pattern preferably has a line width of 20 μm or less and a line interval (pitch) of about 50 μm to 400 μm. The conductive metal portion may have a portion whose line width is wider than 20 μm for the purpose of ground connection or the like. From the viewpoint of moire, the line width of the conductive metal portion is preferably less than 15 μm, more preferably less than 10 μm, and most preferably less than 7 μm.

  In the mesh pattern, the ratio of the light transmitting portion (that is, the aperture ratio) is preferably 85% or more from the viewpoint of visible light transmittance, more preferably 90% or more, and 95% or more. Most preferred. The aperture ratio is the ratio of the portion without fine lines forming the mesh to the whole. For example, the aperture ratio of a square lattice mesh having a line width of 10 μm and a pitch of 200 μm is 90%.

  In FIG. 2, the pattern on the base material formed by the exposure through the mask M and the mask exposure was shown notionally. A silver salt fine particle-containing photosensitive solution is continuously coated on a continuously running support F to form a silver salt fine particle-containing silver photosensitive layer, and then exposed continuously (intermittently) using these masks. The method that is usually done when doing.

  FIG. 2A shows a case where exposure is performed on a support F having a silver photosensitive layer containing a silver photosensitive layer that travels through a mask M, and FIG. It shows a state where the exposure areas corresponding to the mesh pattern are formed continuously and independently. Incidentally, (c) shows that a metal mesh pattern made of metallic silver was formed on a support after exposure and development.

  After the development process, the metal mesh pattern formed by the metallic silver is further subjected to a catching process such as physical development or plating, and then cut into individual mesh pattern units to produce an electromagnetic wave shielding film.

  A mask exposure method according to the present invention is schematically shown in FIG.

  In the present invention, each mesh pattern unit is exposed so as to partially overlap each other.

  FIG. 3A shows this state. In the figure, n, n-1, n + 1, n + 2, etc. indicate the order in which the mask exposure is sequentially performed. In the figure, L is the unit pattern length of the mesh pattern. In the figure, l represents the overlap length with the adjacent mesh pattern. In this example, there are non-mesh portions at both ends, but the same applies even when there are no mesh portions. Here, the n-th pattern is exposed by overlapping with the (n-1) -th pattern by l, and l takes a length in the support transport direction and is subjected to mesh exposure (L) Of 0.2 to 3%. The nth mesh pattern is also partially overlapped and exposed for n + 1.

  In this example, there are non-mesh portions at both ends, but by overlapping these portions, it is possible to continuously produce a conductive film, which is preferable in terms of increasing the efficiency of the plating process. Even when a mask having no non-mesh portions at both ends is used, by overlapping the portions, a film having conductivity can be continuously formed, and the efficiency of the plating process can be increased.

  The overlap between the nth pattern and the (n + 1) th pattern is not necessarily the same as the overlap length between the nth pattern and the (n-1) th pattern. The pattern length (L) of the light transmission part may be in the range of 0.2 to 3%. However, considering the subsequent process, it is preferable in the process that it is the same overlap with the pattern before and after.

  By doing so, it is possible to continuously form the conductive part of the metal mesh pattern formed by exposure and development processing, and it is possible to perform electrolytic plating processing of multiple patterns simultaneously at the time of electrolytic plating. It becomes. It is possible to apply a uniform potential to the entire metal mesh regardless of where the terminal is in contact with the exposed area of the support or the metal mesh portion, and the electrolytic plating process can be continuously performed over a plurality of patterns.

  For example, FIG. 4 shows an example of the electroplating apparatus 16, but if a cathode-side power supply roll 48 </ b> A is provided at the entrance of the charge plating tank 36 and a roll potential is applied, the metal mesh pattern on the traveling support F is electrolyzed. In the plating tank 36, the positive electrode plate 48B is energized through the plating bath solution to cause an electrolytic plating current to flow, and the metal mesh pattern is subjected to electrolytic plating.

  Since it is a continuous electroconductive film, the metal mesh part on a support body becomes a uniform electric potential, and when this enters an electrolytic plating tank, it can plate continuously in an electrolytic tank.

  The metal mesh independent for each pattern as shown in FIG. 2 must be subjected to an electrolytic plating process for each pattern, and the processing load becomes an issue, and continuous processing cannot be performed.

  In the figure, 42A, 42B, and 44 are support rolls, and 62 is a rotating roll.

  Although the mask has been described as an example of a mask having a light transmission part that does not form a mesh as an outer frame of the mesh pattern, the light transmission part of the outer frame is not necessarily required. FIG. 5 shows an example of a mesh pattern when a mask having no light transmission part in the outer frame is used. Even in this case, it is sufficient if there is an overlap between mesh patterns that can substantially ensure conduction, and 0.2 to 3% of the pattern length (L) in the longitudinal direction of the support body of the pattern exposed at once by the mask. It is only necessary that the unit patterns overlap in the range. FIG. 5A shows a mesh pattern formed by mask exposure, and FIG. 5B shows an example of a seamless pattern when these are overlaid and exposed.

  In the present invention, a coating solution containing metal salt fine particles is uniformly applied on a traveling support, dried, and then subjected to mesh pattern exposure sequentially and continuously using a mask on the coating layer. Then, the metal mesh pattern is formed on the support by developing, and then the metal mesh pattern is subjected to a catching process by performing physical development and / or plating, thereby imparting conductivity, thereby providing a magnetic wave shielding film. Manufacturing.

  After the development process, the metal mesh formed by silver development alone is insufficient in conductivity, and physical development process and / or plating process is performed to reinforce the metal mesh pattern and impart conductivity.

  As the plating process, the electroplating process can be performed after the electroless plating process. From the viewpoint of productivity, it is preferable to perform electroplating at a high plating rate after performing electroless plating for a predetermined time. With only electroless plating, the plating process takes time.

  Further, it is possible to process only by electroplating. When performing only by electroplating, it is preferable to perform electroplating with a high current value after performing electroplating with a low current value first. By performing plating at a low current value in the initial stage, local unevenness of plating can be minimized. Therefore, when processing is performed only by electroplating, it is preferable to perform plating processing by gradually increasing the current value using a plurality of electrolytic plating processing apparatuses.

  Since the developed mesh has a high electric resistance value, it is not preferable to perform electroplating at a high current value because the plating thickness may be uneven. When electrolytic plating is performed at a low current value, there is a disadvantage that the growth rate of the plated metal is slow, but even a mesh having a low electrical resistance value can be uniformly plated. The plating process with a low current is performed for a certain period of time, and when the electrical resistance value of the film has dropped to some extent, the current value is increased, the plating growth rate is increased, and the final desired electrical resistance value is achieved. From the viewpoint of production efficiency, this is the most preferable production form.

  The low current value cannot be clearly defined, but may be determined from the growth rate and quality of the plated metal. The same applies to the high current value, and the same applies to the time for processing with a low current value and the time distribution for processing with a high current value.

  In the present invention, it is preferable that the development processing, the physical development processing and / or the plating processing are continuously processed with a roll-to-roll. Since the plating process can be continuously performed and it is not necessary to perform the process for each pattern, the conductivity can be improved efficiently, and a conductive metal mesh pattern having a high electromagnetic shielding ability can be obtained.

  Hereafter, the component requirements used by this invention are demonstrated.

[Support]
As the support used in the present invention, a plastic film, a plastic plate, glass or the like can be used, and a plastic film is preferred.

  Examples of the raw material for the plastic film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate, polyolefins such as polyethylene (PE), polypropylene (PP), polystyrene, and EVA, polyvinyl chloride, and polyvinylidene chloride. Vinyl resin, polyether ether ketone (PEEK), polysulfone (PSF), polyether sulfone (PES), polycarbonate (PC), polyamide, polyimide, acrylic resin, triacetyl cellulose (TAC), cyclic olefin resin, etc. Yes, coating, exposure, development processing and the like are continuously performed while being unwound from the roll-shaped substrate.

  From the viewpoint of transparency, heat resistance, ease of handling and price, the plastic film is preferably a polyethylene terephthalate film or a triacetyl cellulose film.

  Although the plastic film etc. in this invention can also be used by a single layer, it can also be used as a multilayer film combining two or more layers.

  In the present invention, a coating solution containing metal salt fine particles is uniformly coated on a support, dried, and then subjected to mesh pattern exposure using a mask for the coating layer. Specifically, the coating layer containing metal salt fine particles is a layer containing silver salt fine particles as a photosensor (silver salt fine particle-containing photosensitive layer). Binder resin, additives and the like, and can contain a solvent and the like.

[Silver salt fine particle photosensitive layer]
Examples of the silver salt fine particles used include inorganic silver salts such as silver halide and organic silver salts such as silver acetate, but it is preferable to use silver halide having excellent characteristics as an optical sensor.

  The silver halide preferably used in the present invention will be further described.

  In the silver halide used in the present invention, the silver halide technique used in silver salt photographic film, photographic paper, film for printing plate making, emulsion mask for photomask, etc. can be used as it is.

  The halogen element contained in the silver halide may be any of chlorine, bromine, iodine and fluorine, or a combination thereof. For example, silver halide mainly composed of AgCl, AgBr, and AgI is preferably used, and silver halide mainly composed of AgCl is preferably used.

  Here, “silver halide mainly composed of AgCl” refers to silver halide in which the molar fraction of chloride ions in the silver halide composition is 50% or more. The silver halide grains mainly composed of AgCl may contain iodide ions and bromide ions in addition to chloride ions.

  Silver halide is in the form of solid grains. From the viewpoint of image quality of the patterned metallic silver layer formed after exposure and development, the average grain size of silver halide is 0.1 to 1000 nm in terms of sphere equivalent diameter ( 1 μm) is preferable, 0.1 to 100 nm is more preferable, and 1 to 50 nm is even more preferable. The sphere equivalent diameter of silver halide grains refers to the diameter (equivalent circle diameter) when the projected area of silver halide grains is converted into a circle image of the same area. It is determined from the average of 1000 particles using a scanning electron microscope.

  The shape of the silver halide grains is not particularly limited, and may be various shapes such as a spherical shape, a cubic shape, a flat plate shape (hexagonal flat plate shape, triangular flat plate shape, tetragonal flat plate shape, etc.), octahedron shape, and tetrahedron shape. Can be.

In the silver halide used in the present invention, it is also useful to dope metal ions in order to obtain a hard emulsion. In particular, transition metal ions such as rhodium ions and iridium ions are preferably used because a difference between an exposed portion and an unexposed portion tends to occur clearly when a metallic silver image is generated. Transition metal ions represented by rhodium ions and iridium ions can also be compounds having various ligands. Examples of such a ligand include cyanide ions, halogen ions, thiocyanate ions, nitrosyl ions, water, hydroxide ions, and the like. Specific examples of the compound include K ₃ Rh ₂ Br ₉ and K ₂ IrCl ₆ .

In the present invention, the content of the rhodium compound and / or iridium compound contained in the silver halide is 10 ⁻¹⁰ to 10 ⁻² mol / mol Ag with respect to the number of moles of silver in the silver halide. Preferably, it is 10 ⁻⁹ to 10 ⁻³ mol / mol Ag.

  In addition, in the present invention, silver halides containing Pd (II) ions and / or Pd metals can also be preferably used. Pd may be uniformly distributed in the silver halide grains, but is preferably contained in the vicinity of the surface layer of the silver halide grains. Here, Pd “contains in the vicinity of the surface layer of the silver halide grains” means that the Pd content is higher than the other layers within 50 nm in the depth direction from the surface of the silver halide grains. means. Such silver halide grains can be prepared by adding Pd in the course of forming silver halide grains. After adding silver ions and halogen ions to 50% or more of the total addition amount, Pd Is preferably added. It is also preferred that Pd (II) ions be present on the surface of the silver halide by a method such as addition at the time of post-ripening.

  The Pd-containing silver halide grains increase the speed of physical development and electroless plating, increase the production efficiency of a desired electromagnetic shielding material, and contribute to the reduction of production costs. Pd is well known and used as an electroless plating catalyst. However, in the present invention, Pd can be unevenly distributed on the surface layer of silver halide grains, so that extremely expensive Pd can be saved. is there.

In the present invention, the content of Pd ions and / or Pd metals contained in the silver halide is preferably 10 ^{−4 to} 0.5 mol / mol Ag with respect to the number of moles of silver in the silver halide, More preferably, it is 0.01-0.3 mol / mol Ag.

Examples of the Pd compound used include PdCl ₄ and Na ₂ PdCl ₄ .

  In the present invention, in order to further improve the sensitivity as an optical sensor, chemical sensitization performed with a photographic emulsion can be performed. As chemical sensitization, for example, noble metal sensitization such as gold sensitization, chalcogen sensitization such as sulfur sensitization, reduction sensitization or the like can be used.

  Examples of emulsions that can be used in the present invention include color negatives described in Examples of JP-A-11-305396, JP-A-2000-321698, JP-A-13-281815, and JP-A-2002-72429. A film emulsion, a color reversal film emulsion described in JP-A No. 2002-214731, a color photographic paper emulsion described in JP-A No. 2002-107865, and the like can be suitably used.

  Chemically sensitized silver halide grains can also be spectrally sensitized. Preferable spectral sensitizing dyes include cyanine, carbocyanine, dicarbocyanine, complex cyanine, hemicyanine, styryl dye, merocyanine, complex merocyanine, holopolar dye, and the like. Can be used alone or in combination.

  Particularly useful dyes are cyanine dyes, merocyanine dyes, and complex merocyanine dyes. Any of nuclei usually used for cyanine dyes can be used as these basic heterocyclic nuclei. A pyrroline nucleus, an oxazoline nucleus, a thiazoline nucleus, a pyrrole nucleus, an oxazole nucleus, a thiazole nucleus, a selenazole nucleus, an imidazole nucleus, a tetrazole nucleus, a pyridine nucleus, and a nucleus in which an alicyclic hydrocarbon ring is fused to these nuclei; and these A nucleus fused with an aromatic hydrocarbon ring, that is, an indolenine nucleus, a benzindolenin nucleus, an indole nucleus, a benzoxazole nucleus, a naphthoxazole nucleus, a benzothiazole nucleus, a naphthothiazole nucleus, a benzoselenazole nucleus, a benzimidazole nucleus, Such as quinoline nuclei. These nuclei may be substituted on carbon atoms. The merocyanine dye or the complex merocyanine dye includes a pyrazoline-5-one nucleus, a thiohydantoin nucleus, a 2-thiooxazolidine-2,4-dione nucleus, a thiazolidine-2,4-dione nucleus, and a rhodanine nucleus as a nucleus having a ketomethylene structure. 5- to 6-membered heterocycle nuclei such as thiobarbituric acid nuclei can be applied. Particularly preferred sensitizing dyes are near infrared sensitizing dyes. For these dyes, JP-A Nos. 2000-347343, 2004-037711, and 2005-134710 can be referred to.

<binder>
In the silver salt fine particle-containing photosensitive layer of the present invention, the crosslinkable binder (resin) can be used for the purpose of uniformly dispersing the silver salt particles and assisting the adhesion between the silver salt fine particle-containing photosensitive layer and the support. . In the present invention, both the water-insoluble polymer and the water-soluble polymer can be used as the crosslinkable binder, but it is preferable to use a water-soluble polymer.

  Examples of the water-soluble crosslinking binder include polysaccharides such as gelatin, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), starch, cellulose and derivatives thereof, polyethylene oxide, polyvinylamine, chitosan, polylysine, polyacrylic acid, Examples include polyalginic acid, polyhyaluronic acid, carboxycellulose, and the like. These have neutral, anionic, and cationic properties depending on the ionicity of the functional group.

  Since silver halide gelatin emulsion for photography is used as the silver halide grains, gelatin is most preferable as the crosslinkable binder (resin).

  Examples of gelatin include lime-processed gelatin, acid-processed gelatin, and various modified gelatins such as phthalated gelatin and phenylcarbamoylated gelatin.

  The content of the binder contained in the silver salt fine particle-containing photosensitive layer of the present invention is not particularly limited, and can be appropriately determined as long as dispersibility and adhesion can be exhibited. The content of the binder in the silver salt fine particle-containing photosensitive layer is preferably from 1/4 to 100, more preferably from 1/3 to 10, more preferably from 1/2 to 1 in terms of Ag / binder volume ratio. More preferably. Most preferably, it is 1 / 1-2. If the silver salt fine particle-containing photosensitive layer contains a binder of 1/4 or more by Ag / binder volume ratio, the metal particles can easily come into contact with each other in the physical development and / or plating process, and high conductivity can be obtained. Therefore, it is preferable.

  The crosslinkable binder is formed so as to maintain a predetermined film strength by being cross-linked by a cross-linking agent when the silver salt fine particle-containing photosensitive layer is formed.

  The crosslinking agent for the crosslinkable binder is not particularly limited as long as it is an agent that substantially crosslinks only the crosslinkable binder and does not crosslink with the water-soluble compound.

  When the crosslinkable binder is gelatin, vinylsulfone type hardeners and chlorotriazine type hardeners described in JP-A-61-249045 and JP-A-61-245153 can be used. In addition, a thickening agent or a main seasoning agent such as an activator as a spreading agent may be included as necessary.

  Moreover, you may use a hydrazine compound etc. as a method of making a silver halide grain high contrast. Further, a high contrast accelerator or the like may be used.

<solvent>
The solvent used in the silver halide grain-containing layer of the present invention is not particularly limited. For example, water, organic solvents (for example, alcohols such as methanol, ketones such as acetone, amides such as formamide, etc.) Sulfoxides such as dimethyl sulfoxide, esters such as ethyl acetate, ethers, etc.), ionic liquids, and mixed solvents thereof. Since a photographic silver halide gelatin emulsion is used, a solvent mainly containing water is preferred. The solvent mainly composed of water is a solvent containing 70% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more of water. Water alone is also preferred.

[Application]
Various methods are conventionally known as a method for applying a silver halide grain layer. For example, dip coating method, blade coating method, air knife coating method, wire bar coating method, gravure coating method, reverse roll coating method, extrusion type coating method, slide hopper coating method, slot type curtain coating method, slide type curtain Application methods and the like are known.

In the present invention, it is preferable to use a vacuum extrusion coating method by an extrusion coating method using a vacuum chamber. Thereby, it is preferable to apply | coat so that it may become the range of 0.3-1 g / m < ² > as an application quantity of a metal component. Even if there is a change in the surface properties and wettability of the support, the pressure-extrusion extrusion coating method applies a uniform film thickness with almost no change in the wetted position of the coating liquid on the support because the bead portion is decompressed. A membrane can be obtained.

  Since the conventional coating liquid expresses the target performance only by the coating liquid, it is necessary to apply the film with a certain film thickness. However, the functions required for the electromagnetic wave shielding film are the light transmittance and the electromagnetic wave shielding function, and the electromagnetic wave shielding function depends on the electric resistance value. Since the electrical resistance value depends on the metal film thickness after the plating treatment, the silver salt fine particle-containing photosensitive layer may be a thin film. However, it is most preferable to apply a silver halide fine particle-containing photosensitive solution having a high silver / binder ratio as a thin film because a physical development process and a plating process are easier when the metal component is larger and the binder amount is smaller.

[exposure]
In the present invention, the metal salt fine particle-containing photosensitive solution is uniformly applied onto a continuously running support, dried, and then subjected to mesh pattern exposure in the applied layer using a mask in order in the transport direction of the support. The conductive metal mesh pattern is continuously formed as described above by performing the development process, further the physical development process and / or the plating process after performing the process continuously while overlapping a part of the exposed portion by the mask. Get.

  The exposure is preferably contact exposure through a mask, but other methods may be used. As the exposure light source, an electromagnetic wave is used. Examples of the electromagnetic wave include light such as visible light and ultraviolet light, and radiation such as X-rays. Furthermore, a light source having a wavelength distribution may be used for exposure, or a light source having a specific wavelength may be used.

  In the present invention, exposure can be performed using various laser beams. For example, the exposure in the present invention is performed by using a monochromatic high light source such as a gas laser, a light emitting diode, a semiconductor laser, a semiconductor laser, or a second harmonic light source (SHG) that combines a solid state laser using a semiconductor laser and a nonlinear optical crystal A scanning exposure method using density light can be preferably used, and a KrF excimer laser, ArF excimer laser, F2 laser, or the like can also be used.

  In order to make the system compact and quick, exposure is preferably performed using a semiconductor laser, a semiconductor laser, or a second harmonic generation light source (SHG) that combines a solid-state laser and a nonlinear optical crystal. In order to design an apparatus that is particularly compact, quick, long-life, and high in stability, exposure is preferably performed using a semiconductor laser.

  Specifically, an ultraviolet semiconductor, a blue semiconductor laser, a green semiconductor laser, a red semiconductor laser, a near infrared laser, or the like is preferably used as the laser light source.

  The mask is formed of a light-shielding material such as metal and can be manufactured using various known methods. For example, the mask can be manufactured by etching a metal thin film using photolithography.

[Development processing]
In the present invention, the development processing (process) represents from development processing to fixing processing as follows.

  In the present invention, development processing is performed after exposing the original plate for an electromagnetic wave shielding material having a silver halide grain-containing photosensitive layer. The development process is preferably a so-called black-and-white development process that does not contain a color developing agent.

  As the developing solution, in addition to hydroquinones such as hydroquinone, sodium hydroquinonesulfonate, chlorohydroquinone and the like as developing agents, 1-phenyl-3-pyrazolidone, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1- Use in combination with pyrazolidones such as phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone, 1-phenyl-4-methyl-3-pyrazolidone and superadditive developing agents such as N-methylparaaminophenol sulfate. Can do. Further, it is preferable to use a reductone compound such as ascorbic acid or isoascorbic acid in combination with the superadditive developing agent without using hydroquinone.

  In addition, sodium sulfite or potassium sulfite as a preservative, sodium carbonate or potassium carbonate as a buffer, diethanolamine, triethanolamine, diethylaminopropanediol or the like as a development accelerator can be appropriately used in the developing solution.

  The development processing solution used in the development processing can contain an image quality improver for the purpose of improving the image quality. Examples of the image quality improver include nitrogen-containing heterocyclic compounds such as 1-phenyl-5-mercaptotetrazole and 5-methylbenzotriazole. Further, when a lith developer is used, it is particularly preferable to use polyethylene glycol.

  In the present invention, it is preferable that the development processing performed after exposure includes physical development before fixing. The term “physical development before fixing” as used herein refers to a process in which silver ions are supplied from outside the silver halide grains having a latent image by exposure to reinforce developed silver before performing a fixing process described later. As a specific method for supplying silver ions from the developing solution, for example, a method of dissolving silver nitrate or the like in advance in a developing solution and dissolving silver ions, or sodium thiosulfate in the developing solution, Examples include a method in which a silver halide solvent such as ammonium thiocyanate is dissolved, unexposed silver halide is dissolved during development, and development of silver halide grains having a latent image is supplemented.

  In the present invention, it is preferable to use a formulation in which a silver halide solvent is preliminarily dissolved in a developer because a reduction in the transmittance of the film due to fogging in unexposed areas can be suppressed.

  In the development processing in the present invention, after the development of the exposed silver halide grains, fixing processing is performed for the purpose of removing and stabilizing the unexposed silver halide grains. For the fixing treatment in the present invention, a fixer formulation used for photographic films, photographic papers and the like using silver halide grains can be used. The fixing solution used in the fixing process may use sodium thiosulfate, potassium thiosulfate, ammonium thiosulfate, or the like as a fixing agent. Aluminum sulfate, chromium sulfate, or the like can be used as a hardener for fixing. As the fixing agent preservative, sodium sulfite, potassium sulfite, ascorbic acid, erythorbic acid and the like described in the developing solution can be used, and citric acid, oxalic acid, and the like can be used.

  By performing exposure and development processing, a mesh pattern made of metallic silver is formed and a light transmissive portion is also formed.

  In the method for producing an electromagnetic wave shielding material of the present invention, it is particularly preferable to perform development with a fixing solution that does not contain a hardener such as a water-soluble aluminum compound in the fixing solution.

  In the first development processing, it is preferable that the dura is not strong.

  Therefore, it is particularly preferable to perform development processing with a fixing solution that does not contain a hardener such as a water-soluble aluminum compound in the fixing solution.

  On the other hand, as the electromagnetic wave shielding material, it is necessary to give the layer containing the electromagnetic wave shielding metal pattern a certain strength, so after physical development and / or plating treatment, the film needs to be cross-linked to increase the film strength. It is preferable to crosslink and harden the binder resin in the layer containing the metal pattern. For example, when the binder resin is gelatin, aldehyde compounds such as glutaraldehyde, glutaraldehyde sulfite adduct, aluminum chloride, aluminum sulfate, potassium alum etc. It is preferable to cross-link the membrane with a water-soluble aluminum salt. Accordingly, after the physical development or plating treatment bath, for example, a hardening bath containing a gelatin hardening agent is provided, and the binder resin is crosslinked and then dried.

  Alternatively, a crosslinking agent may be included in the physical development and / or plating process to serve as a hardening bath.

  In particular, the hardening bath containing aluminum ions only needs to immerse the electromagnetic wave shielding material in the hardening bath after physical development and / or plating, and the stability of the hardening bath itself is good. This is particularly preferable because a strong film can be obtained.

  The gradation after development processing in the present invention is not particularly limited, but is preferably more than 4.0. When the gradation after the development processing exceeds 4.0, the conductivity of the conductive metal portion can be increased while keeping the transparency of the light transmissive portion high. Examples of means for setting the gradation to 4.0 or higher include the aforementioned doping of rhodium ions and iridium ions.

[Physical development and plating]
In the present invention, for the purpose of imparting conductivity to the metal silver portion formed by the exposure and development processing, physical development and / or plating treatment for supporting the conductive metal particles on the metal silver portion is performed.

  “Physical development” in the present invention means that metal particles such as silver ions are reduced with a reducing agent on metal or metal compound nuclei to deposit metal particles. This physical phenomenon is used for instant B & W film, instant slide film, printing plate manufacturing, and the like, and the technology can be used in the present invention.

  Further, the physical development may be performed simultaneously with the development processing after exposure or separately after the development processing.

  In the present invention, the plating treatment can be performed using electroless plating (chemical reduction plating or displacement plating), electrolytic plating, or both electroless plating and electrolytic plating.

  In the present invention, it is preferable that the plating process is an electroless plating process followed by an electrolytic plating process.

  In the plating treatment, it is also preferable to first perform electrolytic plating at a low current value and then perform electrolytic plating at a high current value.

  Electrolytic plating at a low current value allows uniform plating even on high resistance films, but the growth rate of the plating metal is slow, and electrolytic plating at high current values does not allow uniform plating on high resistance films. However, since the growth rate of the plated metal is fast, the current value and the plating processing time at each current value may be determined from the aspects of quality and production capacity.

  For the electroless plating in the present invention, a known electroless plating technique can be used. For example, an electroless plating technique used for a printed wiring board can be used, and the electroless plating is an electroless copper plating. Preferably there is.

  Chemical species contained in the electroless copper plating solution include copper sulfate and copper chloride, formalin and glyoxylic acid as the reducing agent, EDTA and triethanolamine as the copper ligand, and other bath stabilization and plating film Examples of the additive for improving the smoothness include polyethylene glycol, yellow blood salt, and bipyridine. Examples of the electrolytic copper plating bath include a copper sulfate bath and a copper pyrophosphate bath.

  The plating speed at the time of plating in the present invention can be performed under moderate conditions, and high-speed plating of 5 μm / hr or more is also possible. In the plating treatment, various additives such as a ligand such as EDTA can be used from the viewpoint of improving the stability of the plating solution.

  In addition, as the electrolytic plating treatment, a known electrolytic plating technique can be applied, for example, an electrolytic plating technique used in a printed wiring board or the like can be applied, and the electrolytic plating is electrolytic copper plating. Is preferred. As the plating bath solution, it is preferable to apply an electrolytic copper plating bath solution. Examples of the electrolytic copper plating bath include a copper sulfate bath, a copper pyrophosphate bath, a copper borofluoride bath, and the like. Chemical species contained in the electrolytic copper plating solution include copper sulfate and copper chloride, sulfuric acid that improves the stability and conductivity of the plating solution, and increases the uniform electrodeposition, the dissolution of the anode, and the auxiliary effect of additives As an additive for improving chlorine and bath stabilization and plating denseness, polyethylene oxide, bipyridine and the like can be mentioned.

  An electrolytic plating current is applied from the power supply for plating from the negative electrode side power supply roll to the metal mesh portion on the support, which is the surface to be plated, to perform electrolytic plating. Since the metal mesh pattern is seamlessly continuous, electrolytic plating can be performed continuously.

  The electrolytic plating treatment is preferably performed by arranging two sets of tanks and changing the current value. Moreover, you may perform this 2 or more according to desired plating film thickness (thickness of an electroconductive metal part).

  Thereafter, the long film having the metal mesh pattern subjected to the electrolytic plating treatment is subjected to the same treatment, and then the attached plating solution is removed by an air knife and a water absorption roll, etc., and further carried into a washing tank and washed, Moreover, it is rust-proofed and dried and wound up.

  In this way, the coating solution containing the metal salt fine particles is uniformly applied on the traveling support and dried to form a coating (conductive metal portion) on the mesh pattern-shaped metal silver portion of the photosensitive material used as the coating layer. Is done. Here, it is preferable that a conductive metal part contains 50 mass% or more of silver with respect to the total mass of the metal contained in a conductive metal part, and it is further more preferable to contain 60 mass% or more. If silver is contained in an amount of 50% by mass or more, the time required for physical development and / or plating can be shortened, productivity can be improved, and cost can be reduced. Furthermore, when copper and palladium are used as the conductive metal particles forming the conductive metal part, the total mass of silver, copper and palladium is 80% by mass or more based on the total mass of the metal contained in the conductive metal part. It is preferable that it is 90 mass% or more.

[Conductive metal part]
Next, the conductive metal pattern formed in the present invention will be described.

  In the present invention, the electromagnetic wave shielding mesh pattern made of the conductive metal part is electrically conductive to the metal silver part by physically developing or plating the mesh pattern made of the metal silver part formed by the exposure and development processes described above. It is preferably formed by supporting the conductive metal particles.

  In addition to the silver described above, the conductive metal particles supported on the metallic silver portion by physical development and / or plating treatment are copper, aluminum, nickel, iron, gold, cobalt, tin, stainless steel, tungsten, chromium, titanium. , Palladium, platinum, manganese, zinc, rhodium and other metals, or alloys of these in combination. Copper, aluminum, or nickel particles are preferable from the viewpoint of conductivity, price, and the like. Moreover, when providing magnetic field shielding properties, it is preferable to use paramagnetic metal particles.

  In the conductive metal part, the conductive metal particles contained in the conductive metal part are preferably copper particles from the viewpoint of enhancing contrast and preventing the conductive metal part from being oxidized and fading over time. More preferably, the surface is blackened. The blackening treatment can be performed using a method performed in the printed wiring board field. For example, blackening treatment is performed by treating at 95 ° C. for 2 minutes in an aqueous solution of sodium chlorite (31 g / l), sodium hydroxide (15 g / l), and trisodium phosphate (12 g / l). Can do.

  The conductive metal part preferably contains 50% by mass or more, and more preferably 60% by mass or more of silver with respect to the total mass of the metal contained in the conductive metal part. When silver is contained in an amount of 50% by mass or more, the time required for physical development and / or plating can be shortened, productivity can be improved, and cost can be reduced.

  Furthermore, when copper and palladium are used as the conductive metal particles forming the conductive metal part, the total mass of silver, copper and palladium is 80% by mass or more based on the total mass of the metal contained in the conductive metal part. It is preferable that it is 90 mass% or more.

Since the conductive metal portion in the present invention carries conductive metal particles, good conductivity can be obtained. For this reason, the surface resistivity of the translucent electromagnetic wave shielding film (conductive metal part) of the present invention is preferably 10 ³ Ω / □ or less, more preferably 10 ² Ω / □ or less, more preferably 10Ω. / □ or less is more preferable, and 1.0Ω / □ or less is most preferable.

  In the use of the translucent electromagnetic wave shielding material, the conductive metal portion preferably has a line width of 20 μm or less and a line interval of 50 μm or more. The conductive metal portion may have a portion whose line width is wider than 20 μm for the purpose of ground connection or the like. Further, from the viewpoint of making the image inconspicuous, the line width of the conductive metal portion is preferably less than 15 μm, more preferably less than 10 μm, and most preferably less than 7 μm.

  In the mesh pattern, the ratio of the light transmitting portion (that is, the aperture ratio) is preferably 85% or more from the viewpoint of visible light transmittance, more preferably 90% or more, and 95% or more. Most preferred. The aperture ratio is the ratio of the portion without fine lines forming the mesh to the whole. For example, the aperture ratio of a square lattice mesh having a line width of 10 μm and a pitch of 200 μm is 90%.

[Light transmittance]
In the present invention, the average transmittance in the visible light region is the average value obtained by integrating the transmittances in the visible light region obtained by measuring the transmittance in the visible light region from 400 to 700 nm at least every 5 nm. Defined as

  In measurement, the measurement aperture needs to be sufficiently larger than the mesh pattern described above, and is obtained by measuring at least 100 times larger than the mesh area of the mesh.

  In the present invention, the average transmittance in the visible light region is preferably 80% or more, more preferably 85% or more, and further preferably 90% or more.

[Layer structure of electromagnetic shielding material]
The thickness of the support in the electromagnetic wave shielding material of the present invention is preferably 5 to 200 μm, and more preferably 30 to 150 μm. If it is the range of 5-200 micrometers, the transmittance | permeability of a desired visible light will be obtained and handling will also be easy.

  The thickness of the metallic silver portion provided on the support before physical development and / or plating can be appropriately determined by the coating thickness of the coating solution for the silver halide grain-containing layer applied on the support. . The thickness of the metallic silver part is preferably 30 μm or less, more preferably 20 μm or less, further preferably 0.01 to 9 μm, and most preferably 0.05 to 5 μm.

  As an application of the electromagnetic wave shielding material for the display, the thinner the conductive metal portion, the wider the viewing angle of the display, which is preferable. As the conductive wiring material, thinning and high density are required, and from such a viewpoint, the thickness of the layer made of the conductive metal supported on the conductive metal part is preferably less than 9 μm, It is more preferably 0.1 μm or more and less than 5 μm, and further preferably 0.1 μm or more and less than 3 μm.

  In the present invention, a metallic silver portion having a desired thickness is formed by controlling the coating thickness of the silver salt-containing layer, and the thickness of the layer made of conductive metal particles can be freely controlled by physical development and / or plating treatment. Therefore, even a translucent electromagnetic wave shielding film having a thickness of less than 5 μm, preferably less than 3 μm, can be easily formed.

  Hereinafter, the present invention will be described more specifically with reference to examples of the present invention.

  In addition, the material, usage-amount, ratio, processing content, processing procedure, etc. which are shown in the following Examples can be changed suitably unless it deviates from the meaning of this invention. Accordingly, the scope of the present invention should not be construed as being limited by the specific examples shown below.

Example 1
<< Preparation of a solution containing silver halide grains >>
An emulsion containing silver iodobromide grains (I = 2.5 mol%) having an average equivalent spherical diameter of 0.044 μm and containing 100 g of gelatin per 100 g of Ag in an aqueous medium was prepared. At this time, the Ag / gelatin mass ratio was 10/1, and alkali-treated low molecular weight gelatin having an average molecular weight of 40,000 was used as the gelatin type.

Further, potassium bromide rhodate and potassium chloroiridate were added to this emulsion so as to have a concentration of 10 ⁻⁷ (mol / mol silver), and silver bromide grains were doped with Rh ions and Ir ions.

After adding sodium chloropalladate to this emulsion and further sensitizing gold sulfur with chloroauric acid and sodium thiosulfate, add 10 ^-4 mol of near-infrared sensitizing dye per mol of silver halide. After performing near-infrared sensitization (using (S-1)), hydrazine (H-2) and an amine compound (A-10) as an accelerator were added as a thickening agent.

(H-2): 1-trifluoromethylcarbonyl-2- {4- [2- (2,4-di-tert-pentylphenoxy) butyramide] phenyl} hydrazine (A-10): 1-dimethylamino-2 -Propanol The silver halide grain size was prepared to be 44 nm depending on the temperature at the time of preparation (25 ° C.).

<Application of silver halide-containing solution>
Polyethylene terephthalate was used as a support, and the silver halide-containing liquid was applied by a reduced pressure extrusion coating method so that the amount of silver applied was 0.5 g / m ² .

<< Exposure / Development >>
Line / space = 5 μm / 245 μm, exposure length (mesh exposure pattern length (L) in the longitudinal direction) 2000 mm, and light transmission part of 30 mm on the outer edge of the mesh part. Continuous exposure was performed using a glass mask having a thickness of 10 mm while overlapping the exposure length. As the light source, red semiconductor laser exposure (685 nm) was used.

  Thereafter, development was performed at 25 ° C. for 45 seconds using the following developer, and further development processing was performed using a fixing solution, followed by rinsing with pure water.

(Developer composition)
Hydroquinone 30g
1-phenyl-3,3-dimethylpyrazolidone 1.5 g
Potassium bromide 3.0g
Sodium sulfite 50g
Potassium hydroxide 30g
Boric acid 10g
Nn-Butyldiethanolamine 15g
Water was added to 1 L, and the pH was adjusted to 10.20.

(Fixing solution composition)
240 ml of 72.5% aqueous solution of ammonium thiosulfate
Sodium sulfite 17g
Sodium acetate trihydrate 6.5g
Boric acid 6.0g
Sodium citrate dihydrate 2.0g
Acetic acid 90% aqueous solution 13.6ml
4.7% sulfuric acid 50% aqueous solution
Aluminum sulfate (aqueous solution with an Al ₂ O ₃ equivalent content of 8.1% mass / volume) 26.5 g
Water was added to 1 L and the pH was adjusted to 5.0.

《Physical development》
Using the following physical developer, physical development was performed at 25 ° C. for 300 seconds, followed by washing with water.

(Physical developer)
800ml of pure water
Citric acid 5g
Hydroquinone 7g
Silver nitrate 3g
Water was added to adjust the total volume to 1L.

<Electrolytic plating>
Electrolytic plating was performed using the following electrolytic plating solution under the conditions of 25 degrees and 3 A / cm ² to form an electrolytic copper plating film having a thickness of 5 μm.

80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

Example 2
<< Preparation of a solution containing silver halide grains >>
The same silver halide emulsion as in Example 1 was used.

<Application of silver halide-containing solution>
In the same manner as in Example 1, coating was performed by a reduced pressure extrusion coating method so that the amount of silver applied was 0.5 g / m ² .

<< Exposure / Development >>
Using a glass mask in which a silver halide-containing solution is applied / dried, a line / space = 5 μm / 245 μm, an exposure length of 1800 mm, and a mesh is formed over the entire length of the exposed portion, the exposure length Were continuously exposed while superposing 5 mm. As the light source, red semiconductor laser exposure (685 nm) was used.

  Thereafter, development was performed at 25 ° C. for 45 seconds using the following developer, and further development processing was performed using a fixing solution, followed by rinsing with pure water.

(Developer composition)
Hydroquinone 30g
1-phenyl-3,3-dimethylpyrazolidone 1.5 g
Potassium bromide 3.0g
Sodium sulfite 50g
Potassium hydroxide 30g
Boric acid 10g
Nn-Butyldiethanolamine 15g
Water was added to 1 L, and the pH was adjusted to 10.20.

(Fixing solution composition)
240 ml of 72.5% aqueous solution of ammonium thiosulfate
Sodium sulfite 17g
Sodium acetate trihydrate 6.5g
Boric acid 6.0g
Sodium citrate dihydrate 2.0g
Acetic acid 90% aqueous solution 13.6ml
4.7% sulfuric acid 50% aqueous solution
Aluminum sulfate (aqueous solution with an Al ₂ O ₃ equivalent content of 8.1% mass / volume) 26.5 g
Water was added to 1 L and the pH was adjusted to 5.0.

《Physical development》
Using the following physical developer, physical development was performed at 25 ° C. for 300 seconds, followed by washing with water.

(Physical developer)
800ml of pure water
Citric acid 5g
Hydroquinone 7g
Silver nitrate 3g
Water was added to adjust the total volume to 1L.

<Electrolytic plating>
Electrolytic plating was performed using the following electrolytic plating solution under the conditions of 25 degrees and 3 A / cm ² to form an electrolytic copper plating film of 5 μm, and electromagnetic shielding film 2 was created.

80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

Example 3
<< Preparation of a solution containing silver halide grains >>
The same silver halide emulsion as in Example 1 was used.

<Application of silver halide-containing solution>
In the same manner as in Example 1, coating was performed by a reduced pressure extrusion coating method. The amount of silver applied was 0.8 g / m ² .

<< Exposure / Development >>
Using a glass mask in which a silver halide-containing solution is coated / dried, a line / space = 5 μm / 245 μm, an exposure length of 1500 mm, and a mesh is formed over the entire length of the exposed portion, the exposure length Were continuously exposed while overlapping 30 mm. As the light source, red semiconductor laser exposure (685 nm) was used.

  Thereafter, development was performed at 25 ° C. for 45 seconds using the following developer, and further development processing was performed using a fixing solution, followed by rinsing with pure water.

(Developer composition)
Hydroquinone 30g
1-phenyl-3,3-dimethylpyrazolidone 1.5 g
Potassium bromide 3.0g
Sodium sulfite 50g
Potassium hydroxide 30g
Boric acid 10g
Nn-Butyldiethanolamine 15g
Water was added to 1 L, and the pH was adjusted to 10.20.

(Fixing solution composition)
240 ml of 72.5% aqueous solution of ammonium thiosulfate
Sodium sulfite 17g
Sodium acetate trihydrate 6.5g
Boric acid 6.0g
Sodium citrate dihydrate 2.0g
Acetic acid 90% aqueous solution 13.6ml
4.7% sulfuric acid 50% aqueous solution
Aluminum sulfate (aqueous solution with an Al ₂ O ₃ equivalent content of 8.1% mass / volume) 26.5 g
Water was added to 1 L and the pH was adjusted to 5.0.

《Physical development》
Using the following physical developer, physical development was performed at 25 ° C. for 300 seconds, followed by washing with water.

(Physical developer)
800ml of pure water
Citric acid 5g
Hydroquinone 7g
Silver nitrate 3g
Water was added to adjust the total volume to 1L.

<Electrolytic plating>
Electrolytic plating was performed using the following electrolytic plating solution under the conditions of 25 degrees and 3 A / cm ² to form a 5 μm electrolytic copper plating film, and electromagnetic shield film 3 was created.

80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

Example 4
<< Preparation of a solution containing silver halide grains >>
The same silver halide emulsion as in Example 1 was used.

<Application of silver halide-containing solution>
In the same manner as in Example 1, coating was performed by a reduced pressure extrusion coating method. The amount of silver applied was 0.8 g / m ² .

<< Exposure / Development >>
Using a glass mask in which a silver halide-containing liquid is applied / dried, a line / space = 5 μm / 245 μm, an exposure length of 2000 mm, and a mesh is formed over the entire length of the exposed portion, the exposure length Were continuously exposed while superposing 5 mm. As the light source, red semiconductor laser exposure (685 nm) was used.

  Thereafter, development was performed at 25 ° C. for 45 seconds using the following developer, and further development processing was performed using a fixing solution, followed by rinsing with pure water.

(Developer composition)
Hydroquinone 30g
1-phenyl-3,3-dimethylpyrazolidone 1.5 g
Potassium bromide 3.0g
Sodium sulfite 50g
Potassium hydroxide 30g
Boric acid 10g
Nn-Butyldiethanolamine 15g
Water was added to 1 L, and the pH was adjusted to 10.20.

(Fixing solution composition)
240 ml of 72.5% aqueous solution of ammonium thiosulfate
Sodium sulfite 17g
Sodium acetate trihydrate 6.5g
Boric acid 6.0g
Sodium citrate dihydrate 2.0g
Acetic acid 90% aqueous solution 13.6ml
4.7% sulfuric acid 50% aqueous solution
Aluminum sulfate (aqueous solution with an Al ₂ O ₃ equivalent content of 8.1% mass / volume) 26.5 g
Water was added to 1 L and the pH was adjusted to 5.0.

《Physical development》
Using the following physical developer, physical development was performed at 25 ° C. for 300 seconds, followed by washing with water.

(Physical developer)
800ml of pure water
Citric acid 5g
Hydroquinone 7g
Silver nitrate 3g
Water was added to adjust the total volume to 1L.

<Electrolytic plating>
Electrolytic plating is performed using the following electrolytic plating solution under the conditions of 25 ° C. and 1 A / cm ² to form a 2 μm copper plating film, then the conditions are changed to 3 A / cm ² , and a 3 μm copper plating film is further formed. And the electromagnetic wave shielding film 4 was produced as a plating film of a total of 5 micrometers.

80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

Example 5
<< Preparation of a solution containing silver halide grains >>
The same silver halide emulsion as in Example 1 was used.

<Application of silver halide-containing solution>
In the same manner as in Example 1, coating was performed by a reduced pressure extrusion coating method. The amount of silver applied was 0.8 g / m ² .

<< Exposure / Development >>
Using a glass mask in which a silver halide-containing solution is applied / dried, a line / space = 5 μm / 245 μm, an exposure length of 1800 mm, and a mesh is formed over the entire length of the exposed portion, the exposure length Were continuously exposed while overlapping 40 mm. As the light source, red semiconductor laser exposure (685 nm) was used.

  Thereafter, development was performed at 25 ° C. for 45 seconds using the following developer, and further development processing was performed using a fixing solution, followed by rinsing with pure water.

(Developer composition)
Hydroquinone 30g
1-phenyl-3,3-dimethylpyrazolidone 1.5 g
Potassium bromide 3.0g
Sodium sulfite 50g
Potassium hydroxide 30g
Boric acid 10g
Nn-Butyldiethanolamine 15g
Water was added to 1 L, and the pH was adjusted to 10.20.

(Fixing solution composition)
240 ml of 72.5% aqueous solution of ammonium thiosulfate
Sodium sulfite 17g
Sodium acetate trihydrate 6.5g
Boric acid 6.0g
Sodium citrate dihydrate 2.0g
Acetic acid 90% aqueous solution 13.6ml
4.7% sulfuric acid 50% aqueous solution
Aluminum sulfate (aqueous solution with an Al ₂ O ₃ equivalent content of 8.1% mass / volume) 26.5 g
Water was added to 1 L and the pH was adjusted to 5.0.

《Electroless plating》
Electroless plating was performed using the following Pd catalyst solution and electroless plating solution to form a 3 μm electroless copper plating film.

(Pd catalyst solution)
Palladium sulfate 20mg
Add water to bring the total volume to 1 liter.

(Electroless copper plating solution)
Copper sulfate 0.04 mol Formaldehyde (37% by mass) 0.08 mol Sodium hydroxide 0.10 mol Triethanolamine 0.05 mol Polyethylene glycol 100 ppm
Add water to bring the total volume to 1 liter.

<Electrolytic plating>
Using the following electrolytic plating solution, a copper plating film of 2 μm was further formed under the conditions of 25 ° C. and 3 A / cm ² , and the electromagnetic wave shielding film 5 was produced as a total 5 μm plating film.

80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

Example 6
<< Preparation of a solution containing silver halide grains >>
The same silver halide grain-containing liquid as in Example 1 was used.

<Application of silver halide-containing solution>
In the same manner as in Example 1, coating was performed by a reduced pressure extrusion coating method so that the amount of silver applied was 0.5 g / m ² .

<< Exposure / Development >>
Using a glass mask having a line / space = 5 μm / 245 μm, an exposure length of 1500 mm, and a light transmission part of 30 mm on the outer edge of the mesh part, the exposure length is applied to the coating film coated / dried with the silver halide-containing liquid. Continuous exposure was performed while overlapping the thickness by 20 mm. As the light source, red semiconductor laser exposure (685 nm) was used.

  Thereafter, development was performed at 25 ° C. for 45 seconds using the following developer, and further development processing was performed using a fixing solution, followed by rinsing with pure water.

(Developer composition)
Hydroquinone 30g
1-phenyl-3,3-dimethylpyrazolidone 1.5 g
Potassium bromide 3.0g
Sodium sulfite 50g
Potassium hydroxide 30g
Boric acid 10g
Nn-Butyldiethanolamine 15g
Water was added to 1 L, and the pH was adjusted to 10.20.

(Fixing solution composition)
240 ml of 72.5% aqueous solution of ammonium thiosulfate
Sodium sulfite 17g
Sodium acetate trihydrate 6.5g
Boric acid 6.0g
Sodium citrate dihydrate 2.0g
Acetic acid 90% aqueous solution 13.6ml
4.7% sulfuric acid 50% aqueous solution
Aluminum sulfate (aqueous solution with an Al ₂ O ₃ equivalent content of 8.1% mass / volume) 26.5 g
Water was added to 1 L and the pH was adjusted to 5.0.

《Physical development》
Using the following physical developer, physical development was performed at 25 ° C. for 300 seconds, followed by washing with water.

(Physical developer)
800ml of pure water
Citric acid 5g
Hydroquinone 7g
Silver nitrate 3g
Water was added to adjust the total volume to 1L.

<Electrolytic plating>
Electrolytic plating treatment was performed using the following electrolytic plating solution under the conditions of 25 degrees and 3 A / cm ² to form a 5 μm electrolytic copper plating film, and electromagnetic created a shielding film.

80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

Comparative Example 1
<< Preparation of a solution containing silver halide grains >>
The same silver halide emulsion as in Example 1 was used.

<Application of silver halide-containing solution>
In the same manner as in Example 1, coating was performed by a reduced pressure extrusion coating method so that the amount of silver applied was 0.5 g / m ² .

<< Exposure / Development >>
A grid-like drawing pattern that can give developed silver of line / space = 5 μm / 245 μm is intermittently exposed to a coating film obtained by applying / drying a silver halide-containing solution using a mask having an exposure length of 2000 mm. went. The light source was exposed to a red semiconductor laser (685 nm), developed using the same developer and fixer as in the examples, and then rinsed with pure water.

<Electrolytic plating>
Using the following electrolytic plating solution, electrolytic plating treatment was performed at 25 ° C. under the conditions of 1 A / cm ² to form a 2 μm copper plating film, the conditions were changed to 3 A / cm ² , and a 3 μm copper plating film was further formed. The sample of Comparative Example 1 was formed as a plated film having a total thickness of 5 μm.

(Electrolytic copper plating solution)
80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

Comparative Example 2
<< Preparation of a solution containing silver halide grains >>
The same silver halide emulsion as in Example 1 was used.

<Application of silver halide-containing solution>
In the same manner as in Example 1, coating was performed by a reduced pressure extrusion coating method so that the amount of silver applied was 0.5 g / m ² .

<< Exposure / Development >>
A grid-like drawing pattern that can give developed silver of line / space = 5 μm / 245 μm to a coating film obtained by applying / drying a silver halide-containing solution, with a red semiconductor laser (wavelength 685 nm), DMD (digital mirror device) Were used so as to form an image of the laser light for each exposure head, and continuous exposure was performed. Thereafter, development processing was performed using the same developer and fixing solution as in the example, and then rinsed with pure water.

<Electrolytic plating>
Using the following electrolytic plating solution, electrolytic plating treatment was performed at 25 ° C. under the conditions of 1 A / cm ² to form a 2 μm copper plating film, the conditions were changed to 3 A / cm ² , and a 3 μm copper plating film was further formed. A sample of Comparative Example 2 was formed as a plating film having a total thickness of 5 μm.

(Electrolytic copper plating solution)
80 g of copper sulfate
200g of sulfuric acid
Chloride ion 50ppm
Water was added to adjust the total volume to 1L.

<Evaluation>
For each of the transparent electromagnetic wave shielding film samples having a conductive metal mesh portion obtained in this way, the specific surface resistivity and the transmittance were measured with a resistivity meter (Loresta GP (MCP-T610 type): ( The measurement was performed using Dia Instruments Co., Ltd.) and a spectrophotometer (Hitachi spectrophotometer U-3210: manufactured by Hitachi, Ltd.). In addition, the transmittance | permeability calculated | required as the average value which integrated | accumulated each transmittance | permeability of the visible light region calculated | required by measuring the transmittance | permeability of the visible light region to 400-700 nm at least every 5 nm.

  Each evaluation item was evaluated as follows.

○: Very good Δ: Although there are drawbacks, practical lower limit ×: Not usable.

  Each manufacturing method was evaluated as follows from the viewpoint of device manufacturing cost and production yield.

○: Low cost and high yield △: Standard (acceptable range)
×: expensive or low yield, unusable

  From Table 1, the electromagnetic wave shielding film produced by the production method of the present invention is excellent in both light transmittance and electromagnetic wave shielding properties, and in the production method of the present invention, compared to the conventional method, the cost of the apparatus, In terms of production yield, it is superior to the conventional method.

It is a conceptual diagram which shows the pattern formed with the mask M for exposure, and a mask. It is a conceptual diagram which shows the pattern on the base material formed by exposure through the mask M, and mask exposure. It is a conceptual diagram which shows the method of this invention exposed so that the part of a mesh pattern may overlap. It is a conceptual diagram which shows the example of an electroplating apparatus. An example of a mesh pattern in the case where a mask having no light transmission part is used in the outer frame is shown.

Explanation of symbols

16 Electrolytic plating equipment 36 Charge plating tank 42A, 42B, 44 Support roll 48A Cathode side feeding roll 48B Positive electrode plate 62 Rotating roll

Claims (10)

A coating solution containing metal salt fine particles is uniformly applied on a continuously running support, dried, and then subjected to mesh pattern exposure sequentially and continuously using a mask on the coating layer, followed by development. A metal mesh pattern is formed on a support by treatment, and then a physical development treatment and / or a plating treatment is performed to impart conductivity to the metal mesh pattern to provide an electromagnetic shielding film. In the method, a method for producing an electromagnetic wave shielding film, wherein the mesh pattern exposure to the coating layer on the carrier to be conveyed is exposed so that adjacent mesh patterns partially overlap each other. The overlap when the adjacent mesh patterns are exposed so that they partially overlap each other is in the range of 0.2 to 3% of the longitudinal length of the support of the mesh pattern exposed at once by the mask. The method for producing an electromagnetic wave shielding film according to claim 1. The method for producing an electromagnetic wave shielding film according to claim 1, wherein the mask has a light transmission part that does not form a mesh as an outer frame of the mesh pattern. The method for producing an electromagnetic wave shielding film according to claim 1, wherein the mask does not form a mesh as an outer frame of the mesh pattern and does not have a light transmission part. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 4, wherein the development treatment, the physical development treatment and / or the plating treatment is performed with a roll-to-roll. The method for producing an electromagnetic wave shielding film according to claim 1, wherein the plating treatment includes an electroless plating treatment and an electrolytic plating treatment subsequent thereto. The electromagnetic wave shielding film according to any one of claims 1 to 5, wherein the plating treatment is performed by first performing electrolytic plating at a low current value and then performing electrolytic plating at a high current value. Production method. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 7, wherein the metal salt fine particles are metal halide fine particles. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 8, wherein the coating amount of the metal component of the metal halide fine particles is 0.3 to 1 g / m ² by extrusion extrusion coating under reduced pressure. . An electromagnetic wave shielding film produced by the method for producing an electromagnetic wave shielding film according to claim 1.

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