JPWO2007102393A1 - Method for manufacturing electromagnetic shielding film, and electromagnetic shielding film - Google Patents

Abstract

Providing a production method of an electromagnetic wave shielding film with high productivity, and further providing an electromagnetic wave shielding film having a high electromagnetic wave shielding function, an excellent antireflection function, and a high near-infrared absorption function are provided on a support. An electromagnetic wave shielding film original plate provided with a layer containing silver halide grains is exposed to light and developed to form a mesh-like metal part, and then a layer having an antireflection function is formed by coating. This is achieved with an electromagnetic wave shielding film obtained by the method for producing an electromagnetic wave shielding film.

Description

  The present invention relates to a method for producing an electromagnetic wave shielding film that shields electromagnetic waves generated from electronic devices such as mobile phones, microwave ovens, CRTs, and flat panel displays, and an electromagnetic wave shielding film obtained by the production method.

  In recent years, there has been an increasing need to reduce electromagnetic interference (EMI) due to increased use of electronic devices. It has been pointed out that EMI causes malfunctions and failures of electronic and electrical equipment, and also harms the human body. For this reason, electronic devices are required to suppress the intensity of electromagnetic wave emission within the standards or regulations.

  In particular, the plasma display panel (PDP) generates electromagnetic waves in principle because it is based on the principle that a rare gas is made into a plasma state to emit ultraviolet rays and the phosphor emits light with this light. In addition, near infrared rays are also emitted at this time, which causes malfunction of an operating element such as a remote controller.

  The electromagnetic wave shielding ability can be simply expressed by a surface resistance value, 10 Ω / □ or less is required for a light-transmitting electromagnetic wave shielding film for PDP, and 2 Ω / □ or less for a consumer plasma television using PDP. The necessity is high, and extremely high conductivity of 0.2Ω / □ or less is more desirable.

  In order to achieve such high electromagnetic shielding properties, several methods have been proposed so far. For example, the method of attaching an infrared absorbing film to a glass plate baked with a metal mesh having a high aperture ratio is complicated and the manufacturing process for baking the metal mesh is complicated and requires skill in production, and the process time There was a problem that it took a long time. Since the developed silver obtained from the silver halide grains is metallic silver, it is considered to produce a metallic silver mesh by a manufacturing method applying photographic development. When a photosensitive material having a layer containing silver halide grains is exposed and developed in a mesh shape, a conductive metal silver portion in which silver particles are gathered in a mesh shape is formed (for example, see Patent Document 1).

  Other functions required for the PDP include an antireflection layer for preventing reflection of external light, a near infrared absorbing layer for shielding near infrared rays, a color tone correcting layer for correcting color balance, and the like. Since each functional filter has been produced and bonded individually, the manufacturing process is complicated, complicated, requires skill in production, and takes a long time. It was.

  Accordingly, studies have been made to solve this problem by integrating the above functional layers on a single support.

  However, since the physical and chemical properties and characteristics of each functional layer are different, it has been found that simple integration may cause a decrease in function or a great load on the manufacturing process.

For example, a layer containing silver halide grains needs to have a high silver to binder ratio in order to increase the conductivity of the formed mesh pattern. There is an attempt to disperse the near-infrared shielding layer in a hydrophobic plasticizer because of its configuration, using a non-aqueous organic solvent (see, for example, Patent Document 2), but close to the layer containing silver halide grains. On the other hand, it is a factor that decreases productivity.
JP 2004-221564 A JP 2005-099820 A

  An object of the present invention is to provide an electromagnetic wave shielding film having a high productivity and an electromagnetic wave shielding film having a high electromagnetic wave shielding function, an excellent antireflection function, and a high near-infrared absorption function produced by the production method. Is.

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

  1. An electromagnetic wave shielding film master having a layer containing photosensitive silver halide grains on a support is exposed to light and developed to form a mesh-like metal portion, and then a layer having an antireflection function is formed by coating. The manufacturing method of the electromagnetic wave shielding film characterized by the above-mentioned.

  2. 2. The method for producing an electromagnetic wave shielding film as described in 1 above, wherein the layer having an antireflection function is formed on the back surface of a support having a layer having an electromagnetic wave shielding function.

  3. 3. The method for producing an electromagnetic wave shielding film as described in 1 or 2 above, wherein the layer having an antireflection function comprises a plurality of light-transmitting layers containing inorganic fine particles and having different refractive indexes.

  4). 4. The electromagnetic wave shielding film according to any one of 1 to 3 above, wherein the layer containing the photosensitive silver halide grains is provided after providing a layer having a near-infrared absorbing function on a support. Production method.

  5). 5. The method for producing an electromagnetic wave shielding film according to any one of 1 to 4, wherein the layer containing the photosensitive silver halide grains is provided simultaneously with a layer having a near infrared absorption function on a support.

  6). 6. The layer according to 4 or 5 above, wherein the layer containing the photosensitive silver halide grains and the layer having a near infrared absorption function are formed by simultaneous multilayer coating by a slide hopper type coating device or a slide type curtain coating device. Manufacturing method of electromagnetic wave shielding film.

  7. 7. The method for producing an electromagnetic wave shielding film according to any one of 1 to 6, wherein the layer having an antireflection function is formed by successive multilayer coating using a slot type coating device.

  8). A metal having a mesh-like electromagnetic wave shielding function by subjecting the original plate for an electromagnetic wave shielding film provided with a layer containing photosensitive silver halide grains to exposure and development treatment, and further physical development treatment and / or plating treatment. 8. The method for producing an electromagnetic wave shielding film according to any one of 1 to 7, wherein a layer having an antireflection function is applied and formed after the layer is formed.

  9. 9. An electromagnetic wave shielding film produced by the method for producing an electromagnetic wave shielding film according to any one of 1 to 8 above.

  By the method for producing an electromagnetic wave shielding film of the present invention, an electromagnetic wave shielding film having both high electromagnetic wave shielding properties and high near-infrared absorptivity and further having an excellent antireflection function could be provided.

  In the method for producing an electromagnetic wave shielding film of the present invention, a mesh-shaped metal part is formed by exposing and developing an original plate for an electromagnetic wave shielding film in which a layer containing photosensitive silver halide grains is provided on a support. A layer having an antireflection function is formed by coating.

  In the present invention, a layer containing silver halide grains (silver halide grain-containing layer) is provided on the support in order to exhibit an electromagnetic wave shielding function. The silver halide grain-containing layer can contain a binder, an activator and the like in addition to the silver halide grains.

  Examples of the silver halide grains used in the present invention include inorganic silver halide grains such as silver halide and organic silver halide grains such as silver behenate. It is preferable to use it. As the silver halide preferably used in the present invention, for example, silver halide mainly composed of AgCl, AgBr, and AgI is preferably used. In order to obtain metallic silver having good conductivity, fine particles having high sensitivity are preferable, and iodine is used. A silver halide mainly composed of AgBr containing or AgCl containing bromine is preferably used.

  When silver halide grains are developed into metallic silver grains, the contact area needs to be as large as possible for electricity to flow from grain to grain. For that purpose, the smaller the particle size, the better. However, the small particles tend to aggregate and form a large lump, and the contact area is conversely reduced, so there is an optimum particle size.

  The average grain size of the silver halide is preferably 1 to 1000 nm (1 μm), more preferably 1 to 100 nm, in terms of a sphere equivalent diameter. The sphere equivalent diameter of silver halide grains is the diameter of grains having the same volume and having a spherical shape. The size of the silver halide grains is the temperature at the time of preparation of the silver halide grains, pAg, grain size control agent such as 1-phenyl-5 mercaptotetrazole, 2-mercaptobenzimidazole, benztriazole, tetrazaindene compounds. , Nucleic acid derivatives, thioether compounds and the like can be used in appropriate combinations.

  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 order to increase the sensitivity, tabular grains having an aspect ratio of 2 or more, 4 or more, 8 or more, and 16 or less can be preferably used. The particle size distribution may be wide or narrow, but a narrow distribution is preferable in order to obtain high conductivity and increase the aperture ratio. The monodispersity known in the photographic industry is preferably 100 or less, more preferably 30 or less. From the viewpoint of facilitating the flow of electricity, the larger the contact area between the generated particles, the better the shape of the particles.Thus, the flat and the larger the aspect ratio, the better. A ratio exists.

  The silver halide used in the present invention may further contain other elements. For example, in a photographic emulsion, it is also useful to dope metal ions used to obtain a high-contrast emulsion. In particular, transition metal ions such as rhodium ions, ruthenium ions, and iridium ions are preferably used because a difference between an exposed portion and an unexposed portion easily occurs when a metal 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 potassium bromide rhodate and potassium iridate.

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, Pd ions, Pt ions, Pd metals and / or silver halides containing Pt metals can also be preferably used. Pd and Pt may be uniformly distributed in the silver halide grains, but are preferably contained in the vicinity of the surface layer of the silver halide grains. In the present invention, the content of Pd ions and / or Pd metals contained in the silver halide is preferably 10 ^{−6 to} 0.1 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.

  In the present invention, chemical sensitization performed on a photographic emulsion can be performed to further improve sensitivity. As chemical sensitization, for example, noble metal sensitization such as gold, palladium, platinum sensitization, chalcogen sensitization such as sulfur sensitization with inorganic sulfur or organic sulfur compound, reduction sensitization such as tin chloride, hydrazine, etc. are used. be able to.

  Chemically sensitized silver halide grains can be spectrally sensitized. Preferred 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.
In the exposure of silver halide grains, a near-infrared sensitizing dye is preferably used when a near-infrared laser or the like is applied. For these dyes, reference can be made to JP-A Nos. 2000-347343, 2004-037711 and 2005-134710. Particularly preferred specific examples are shown below.

  These sensitizing dyes may be used alone or in combination. A combination of sensitizing dyes is often used for the purpose of supersensitization.

  In order to incorporate these sensitizing dyes in a silver halide emulsion, they may be dispersed directly in the emulsion, or water, methanol, propanol, methyl cellosolve, 2,2,3,3-tetrafluoro A solvent such as propanol may be added alone or in a mixed solvent and added to the emulsion. Further, as described in JP-B Nos. 44-23389, 44-27555, and 57-22089, an acid or base is allowed to coexist to form an aqueous solution, or US Pat. No. 3,822,135, As described in each specification of US Pat. No. 4,006,025, an aqueous solution or a colloidal dispersion prepared by coexisting a surfactant such as sodium dodecylbenzenesulfonate may be added to the emulsion. Further, after dissolving in a substantially immiscible solvent such as phenoxyethanol, water or a hydrophilic colloid dispersion may be added to the emulsion. As described in JP-A-53-102733 and JP-A-58-105141, it may be directly dispersed in a hydrophilic colloid and the dispersion may be added to the emulsion.

  In the present invention, the electromagnetic wave shielding film has an antireflection layer on the same support. The antireflection layer may be formed on a layer having a mesh-like metal part formed by exposing and developing a layer containing silver halide grains, but an antireflection layer is provided on the back side of the support. It is preferable. By finding that the back side can increase the adhesion strength of the antireflection layer by the surface treatment, and that the antireflection layer cannot be sufficiently smooth when formed on a layer having a mesh-like metal part. .

  The layer having an antireflection function according to the present invention is preferably composed of a plurality of light transmissive layers having different refractive indexes, and is composed of a high refractive index layer, a medium refractive index layer, and a low refractive index layer containing inorganic fine particles. More preferably. The layers having different refractive indexes are adjusted according to the kind of inorganic fine particles contained therein, the particle diameter, the added amount, the kind of resin binder, and the like.

  The refractive index of the high refractive index layer is preferably 1.55 to 2.30, and more preferably 1.57 to 2.20. The refractive index of the medium refractive index layer is adjusted so as to be an intermediate value between the refractive index of the base film and the refractive index of the high refractive index layer. The refractive index of the middle refractive index layer is preferably 1.55 to 1.80. The refractive index of the low refractive index layer is preferably 1.46 or less, and particularly preferably 1.3 to 1.45.

  The thickness of each layer is preferably 5 nm to 0.5 μm, more preferably 10 nm to 0.3 μm, and most preferably 30 nm to 0.2 μm.

  The haze of the metal oxide layer is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less. The strength of the metal oxide layer is preferably 3H or higher, and most preferably 4H or higher, with a pencil hardness of 1 kg. When the metal oxide layer is formed by coating, it is preferable to include inorganic fine particles and a binder polymer.

  The inorganic fine particles used for the metal oxide layer such as the middle refractive index layer or the high refractive index layer preferably have a refractive index of 1.80 to 2.80, and more preferably 1.90 to 2.80. . The primary particles of the inorganic fine particles preferably have a mass average diameter of 1 to 150 nm, more preferably 1 to 100 nm, and most preferably 1 to 80 nm.

The mass average diameter of the inorganic fine particles in the layer is preferably 1 to 200 nm, more preferably 5 to 150 nm, still more preferably 10 to 100 nm, and most preferably 10 to 80 nm. If the average particle diameter of the inorganic fine particles is 20 to 30 nm or more, it is measured by a light scattering method, and if it is 20 to 30 nm or less, it is measured by an electron micrograph. The specific surface area of the inorganic fine particles, a measured value by the BET method, is preferably from 10 to 400 m ² / g, more preferably from 20 to 200 m ² / g, a 30 to 150 m ² / g Is most preferred.

  The inorganic fine particles are particles formed from a metal oxide. Examples of metal oxides or sulfides include titanium dioxide (eg, rutile, rutile / anatase mixed crystal, anatase, amorphous structure), tin oxide, indium oxide, ITO, zinc oxide, zirconium oxide, and the like. Of these, titanium dioxide, tin oxide, and indium oxide are particularly preferable. The inorganic fine particles can contain oxides of these metals as main components and further contain other elements. The main component means a component having the largest content (mass%) among the components constituting the particles. Examples of other elements include Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, and S.

  The inorganic fine particles may be surface-treated. The surface treatment can be performed using an inorganic compound or an organic compound. Examples of inorganic compounds used for the surface treatment include alumina, silica, zirconium oxide and iron oxide. Of these, alumina and silica are preferable. Examples of the organic compound used for the surface treatment include polyols, alkanolamines, stearic acid, silane coupling agents, and titanate coupling agents. Of these, a silane coupling agent is most preferable. It may be processed by combining two or more types of surface treatments.

  The shape of the inorganic fine particles is preferably a rice grain shape, a spherical shape, a cubic shape, a layer shape, a spindle shape or an indefinite shape. Two or more kinds of inorganic fine particles may be used in combination in the metal oxide layer.

  The ratio of the inorganic fine particles in the metal oxide layer is preferably 5 to 90% by volume, more preferably 10 to 65% by volume, and still more preferably 20 to 55% by volume.

  The inorganic fine particles are used in a coating liquid for forming a metal oxide layer in a dispersion state dispersed in a medium. As the dispersion solvent for the inorganic fine particles, it is preferable to use a liquid having a boiling point of 60 to 170 ° C.

  Specific examples of the dispersing solvent include water, alcohol (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ester (eg, methyl acetate, ethyl acetate). , Propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (eg hexane, cyclohexane), aromatic hydrocarbons (eg benzene, toluene, xylene), amides (eg Dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ether (eg, diethyl ether, dioxane, tetrahydrofuran), ether alcohol (eg, 1-methoxy-2-propanol). It is. Of these, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are particularly preferable.

  The inorganic fine particles can be dispersed in the medium using a disperser. Examples of the disperser include a sand grinder mill (for example, a bead mill with pins), a high-speed impeller mill, a pebble mill, a roller mill, an attritor, and a colloid mill. A sand grinder mill and a high-speed impeller mill are particularly preferred. Further, preliminary dispersion processing may be performed. Examples of the disperser used for the preliminary dispersion treatment include a ball mill, a three-roll mill, a kneader, and an extruder.

  The metal oxide layer preferably uses a polymer having a crosslinked structure (hereinafter also referred to as “crosslinked polymer”) as a binder polymer. Examples of the crosslinked polymer include polymers having a saturated hydrocarbon chain such as polyolefin (hereinafter collectively referred to as “polyolefin”), crosslinked products such as polyether, polyurea, polyurethane, polyester, polyamine, polyamide and melamine resin. Among them, a crosslinked product of polyolefin, polyether and polyurethane is preferred, a crosslinked product of polyolefin and polyether is more preferred, and a crosslinked product of polyolefin is most preferred.

  Further, it is further preferable that the crosslinked polymer has an anionic group. The anionic group has a function of maintaining the dispersed state of the inorganic fine particles, and the crosslinked structure has a function of imparting a film forming ability to the polymer and strengthening the film. The anionic group may be directly bonded to the polymer chain, or may be bonded to the polymer chain via a linking group, but may be bonded to the main chain as a side chain via the linking group. preferable.

  The refractive index of the low refractive index layer used in the present invention is preferably 1.46 or less, particularly preferably 1.3 to 1.45. The low refractive index layer is formed by a sol-gel method using silicon alkoxide as a coating composition. Can be formed. Or it can be set as a low-refractive-index layer using a fluororesin. In particular, it is preferably composed of a cured product of a thermosetting or ionizing radiation curable fluorine-containing resin and ultrafine particles of silicon oxide. The silicon oxide ultrafine particles may be composite particles having porous particles described later and a coating layer provided on the surface of the porous particles, or hollow particles filled with a solvent, gas, or porous substance inside. preferable.

  The cured product preferably has a dynamic friction coefficient of 0.02 to 0.2, and a pure water contact angle of 90 to 130 °. Examples of the curable fluorine-containing resin include perfluoroalkyl group-containing silane compounds (for example, (heptadecafluoro-1,1,2,2-tetradecyl) triethoxysilane) and fluorine-containing copolymers (crosslinkable groups). As a structural unit). Specific examples of the fluorine-containing monomer unit include, for example, hexafluoroethylene, hexafluoropropylene, tetrafluoroethylene, fluoroolefins (for example, vinylidene fluoride perfluoro-2,2-dimethyl-1,3-dioxole, fluoroethylene, etc. Etc.), fluorinated alkyl ester derivatives of (meth) acrylic acid (for example, Biscoat 6FM (manufactured by Osaka Organic Chemical), M-2020 (manufactured by Daikin), etc.), fluorinated vinyl ethers, and the like. As a monomer having a crosslinkable group, in addition to a (meth) acrylate monomer having a crosslinkable functional group in the molecule in advance such as glycidyl methacrylate, it has a carboxyl group, an amino group, a hydroxyl group, a sulfonic acid group, etc. (meth) Examples include acrylate monomers (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, etc.). It is described in JP-A-10-25388 and JP-A-10-147739 that a crosslinked structure can be introduced after copolymerization.

  Moreover, not only the polymer which uses the said fluorine-containing monomer as a structural unit but the copolymer with the monomer which does not contain a fluorine atom can be used. There are no particular limitations on the monomer units that can be used in combination, for example, acrylic esters (methyl acrylate, methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate), methacrylic esters (methyl methacrylate, ethyl methacrylate). Butyl methacrylate, ethylene glycol dimethacrylate, etc.), styrene derivatives (styrene, divinylbenzene, α-methylstyrene, vinyltoluene, etc.), acrylamides (Nt-butylacrylamide, N-cyclohexylacrylamide, etc.), methacrylamides , Acrylonitrile derivatives, etc., olefins (ethylene, propylene, isoprene, vinylidene chloride, vinyl chloride, etc.), vinyl ethers (methyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate) Le, vinyl cinnamate) may be mentioned.

  In order to improve the scratch resistance, it is preferable to add silicon oxide fine particles to the fluorine-containing resin used for forming the low refractive index layer. The addition amount is adjusted in consideration of the refractive index and scratch resistance. As the silicon oxide fine particles, silica sol dispersed in a commercially available organic solvent can be added to the coating composition as it is, or various commercially available silica powders can be dispersed in an organic solvent and used.

  In the present invention, an electromagnetic wave shielding film master provided with a layer containing photosensitive silver halide grains is exposed to light and developed to form a mesh-like metal part, and then a layer having an antireflection function is formed by coating. It is characterized by doing. That is, we have found an important causal relationship regarding which of the layer having the mesh-like metal portion and the layer having the antireflection function should be formed first, and have arrived at the present invention.

First of all, contrary to the present invention, after coating and forming a layer having an antireflection function on a support first, a layer containing photosensitive silver halide grains is contained in the layer having an antireflection function. It has been found that some of the inorganic fine particles fall off and contaminate the inside of the production process for forming a layer containing photosensitive silver halide grains, which can cause coating stripes and spot failures.
Second, contrary to the present invention, after coating and forming a layer having an antireflection function on a support, exposure and development are performed on an original plate for an electromagnetic wave shielding film provided with a layer containing photosensitive silver halide grains. It has been found that when a mesh-like metal part is formed by treatment, the antireflection function is significantly reduced, the haze value is increased, the translucency is lowered, or spot-like defects are generated. This is because the inorganic fine particles contained in the layer having an antireflection function, particularly silicon oxide fine particles, are dissolved in the alkaline environment of the developing solution, or the dispersion stability of the inorganic fine particles is lowered and aggregation occurs. It is estimated that

  Thirdly, as described above, since the antireflection layer is generally applied using a non-aqueous organic solvent for the constituent material, charging of the support must be avoided in the application process. For this reason, it is necessary not only to have grounding equipment and explosion-proof measures, but also to apply at low speed. If a layer having a mesh-like metal part is provided in advance as in the present invention, the support can be prevented from being charged almost at all, so that high-speed coating is possible.

  In the electromagnetic wave shielding film of the present invention, it is preferable to increase the photographic gradation of the layer containing silver halide grains. As a method therefor, there is a method of narrowing the particle size distribution of silver halide grains, and it is known to use a hydrazine compound or a tetrazolium compound as a contrast enhancer for plate making. A hydrazine compound is a compound having a —NHNH— group, and a typical one is represented by the following general formula.

T-NHNHCO-V, T-NHNHCOCO-V
In the formula, each T represents an optionally substituted aryl group or heterocyclic group. The aryl group represented by T includes a benzene ring or a naphthalene ring, and this ring may have a substituent, and as a preferable substituent, a linear or branched alkyl group (preferably having 1 to 20 carbon atoms). Methyl group, ethyl group, isopropyl group, n-dodecyl group, etc.), alkoxy group (preferably C2-C21 methoxy group, ethoxy group, etc.), aliphatic acylamino group (preferably C2-C21 alkyl group) An acetylamino group, a heptylamino group, etc.), an aromatic acylamino group, and the like. Besides these, for example, a substituted or unsubstituted aromatic ring as described above is -CONH-, -O-, Also included are those bonded by a linking group such as —SO ₂ NH—, —NHCONH—, —CH ₂ CHN— and the like. V represents a hydrogen atom, an optionally substituted alkyl group (methyl group, ethyl group, butyl, trifluoromethyl group, etc.), aryl group (phenyl group, naphthyl group), heterocyclic group (pyridyl group, piperidyl group, pyrrolidyl group) , Furanyl group, thiophene group, pyrrole group and the like).

  The hydrazine compound can be synthesized with reference to the description in US Pat. No. 4,269,929. The hydrazine compound can be contained in the silver halide grain layer, in the hydrophilic colloid layer adjacent to the silver halide grain layer, or in another hydrophilic colloid layer. Particularly preferred hydrazine compounds are listed below.

(H-1): 1-trifluoromethylcarbonyl-2-{[4- (3-n-butylureido) phenyl]} hydrazine (H-2): 1-trifluoromethylcarbonyl-2- {4- [ 2- (2,4-Di-tert-pentylphenoxy) butyramide] phenyl} hydrazine (H-3): 1- (2,2,6,6-tetramethylpiperidyl-4-amino-oxalyl) -2- { 4- [2- (2,4-di-tert-pentylphenoxy) butyramide] phenyl} hydrazine (H-4): 1- (2,2,6,6-tetramethylpiperidyl-4-amino-oxalyl)- 2- {4- [2- (2,4-di-t-pentylphenoxy) butyramide] phenylsulfonamidophenyl} hydrazine (H-5): 1- (2,2,6,6-tetramethylpipe Lysyl-4-amino-oxalyl) -2- (4- (3- (4-chlorophenyl-4-phenyl-3-thia-butanamide) benzenesulfonamido) phenyl) hydrazine (H-6): 1- (2, 2,6,6-tetramethylpiperidyl-4-amino-oxalyl) -2- (4- (3-thia-6,9,12,15-tetraoxatricosanamide) benzenesulfonamido) phenylhydrazine (H- 7): 1- (1-Methylenecarbonylpyridinium) -2- (4- (3-thia-6,9,12,15-tetraoxatricosanamide) benzenesulfonamido) phenylhydrazine chloride.

  Particularly preferred hydrazine compounds are those in which a sulfonamidophenyl group is substituted as the T group and a trifluoromethyl group is substituted as the V group. The oxalyl group bonded to hydrazine is particularly preferably an optionally substituted piperidylamino group. Specific examples of the tetrazolium compound are shown below.

(T-1): 2,3-di (p-methylphenyl) -5-phenyltetrazolium chloride (T-2): 2,3-di (p-ethylphenyl) -5-phenyltetrazolium chloride (T-3) ): 2,3,5-tri-p-methylphenyltetrazolium chloride (T-4): 2,3-diphenyl-5- (p-methoxyphenyl) tetrazolium chloride (T-5): 2,3-di ( o-methylphenyl) -5-phenyltetrazolium chloride (T-6): 2,3,5-tri-p-methoxyphenyltetrazolium chloride (T-7): 2,3-di (o-methylphenyl) -5 -Phenyltetrazolium chloride (T-8): 2,3-di (m-methylphenyl) -5-phenyltetrazolium chloride (T-9): 2,3,5-tri-p-e Carboxymethyl phenyl tetrazolium chloride.

  These can be used with reference to the description of JP-B-5-58175, and can be used in combination with a hydrazine compound in some cases.

  When hydrazine is used as a thickening agent, an amine compound or a pyridine compound is used to enhance the reducing action of hydrazine. A typical amine compound can be represented by the following general formula containing at least one nitrogen atom.

RN (Z) -Q, RN (Z) -LN (W) -Q
R, Q, Z and W in the formula represent an alkyl group having 2 to 30 carbon atoms which may be substituted. In addition, these alkyl group chains may be bonded with a heteroatom such as nitrogen, sulfur or oxygen. R and Z, or Q and W may form a saturated and unsaturated ring with each other. L represents a divalent linking group. This linking group may contain a heteroatom such as sulfur, oxygen, and nitrogen. The linking group of L can have 1 to 200 carbon atoms, 1 to 30 sulfur atoms, 1 to 20 nitrogen atoms, 1 to 40 oxygen atoms, but is particularly limited is not. Specific examples of these amine compounds are shown below.

(A-1): Diethylaminoethanol (A-2): Dimethylamino-1
(A-3): 2-propanediol (A-4): 5-amino-1-pentanol (A-5): diethylamine (A-6): methylamine (A-7): triethylamine (A-8) ): Dipropylamine (A-9): 3-dimethylamino-1-propanol (A-10): 1-dimethylamino-2-propanol (A-11): Bis (dimethylaminotetraethoxy) thioether (A- 12): Bis (diethylaminopentaethoxy) thioether (A-13): Bis (piperidinotetraethoxy) thioether (A-14): Bis (piperidinoethoxyethyl) thioether (A-15): Bis (Nipeco Tindiethoxy) thioether (A-16): bis (dicyanoethylaminodiethoxy) ether (A-17): bis (dieto) Ciethylaminotetraethoxy) ether (A-18): 5-dibutylaminoethylcarbamoylbenzotriazole (A-19): 5-morpholinoethylcarbamoylbenzotriazole (A-20): 5- (2-methylimidazol-2- Ethylene) carbamoylbenzotriazole (A-21): 5-dimethylaminoethylureylenebenzotriazole (A-22): 5-diethylaminoethylureylenebenzotriazole (A-23): 1-diethylamino-2- (6-amino) Purine) ethane (A-24): 1- (dimethylaminoethyl) -5-mercaptotetrazole (A-25): 1-piperidinoethyl 5-mercaptotetrazole (A-26): 1-dimethylamino-5-mercaptotetrazole ( A-27): - mercapto-5-dimethylaminoethyl Chi punch line thiadiazole (A-28): 1- mercapto-2-morpholinoethane.

  As the amine compound that promotes the reducing action of the hydrazine compound, it is particularly preferable that the molecule has at least one piperidine ring or pyrrolidine ring, at least one thioether bond, and at least two ether bonds.

  As compounds that promote the reduction action of hydrazine, pyridinium compounds and phosphonium compounds are used in addition to amine compounds. Since onium compounds are positively charged, they are considered to promote high contrast by adsorbing to negatively charged silver halide grains and accelerating electron injection from the developing agent during development. ing. For preferred pyridinium compounds, reference can be made to the bispyridinium compounds disclosed in JP-A-5-53231 and JP-A-6-242534. Particularly preferred pyridinium compounds are those in which a bispyridinium body is formed by linking at the 1-position or 4-position of pyridinium. In the salt, chlorine ions, bromine ions and the like are preferable as the halogen anion, and other examples include boron tetrafluoride ions and perchlorate ions, but chlorine ions or boron tetrafluoride ions are preferable. Preferred bispyridinium compounds are shown below.

(B-1): 1,1'-dimethyl-4,4'-bipyridinium dichloride (B-2): 1,1'-dibenzyl-4,4'-bipyridinium dichloride (B-3): 1,1 '-Diheptyl-4,4'-bipyridinium dichloride (B-4): 1,1'-di-n-octyl-4,4'-bipyridinium dichloride (B-5): 4,4'-dimethyl-1,1 '-Bipyridinium dichloride (B-6): 4,4'-dibenzyl-1,1'-bipyridinium dichloride (B-7): 4,4'-diheptyl-1,1'-bipyridinium dichloride (B-8): 4,4'-di-n-octyl-1,1'-bipyridinium dichloride (B-9): bis (4,4'-diacetamide-1,1'-tetramethylenepyridinium) dichlori .

  The hydrazine compound acts on the high-concentration high-contrast, but the leg high-contrast is insufficient, so as an attempt to improve this, a technique using an oxidized form of the developing agent generated during development is used. Also good. The presence of a redox compound that reacts with the oxidized oxidant of the developing agent and the release of an inhibitor that suppresses the leg from this compound enhances the sharpness of the image. Oxidation of the developing agent is generated as the development progresses, and is therefore related to the reduction rate of the particles. If a development nucleus having a high reduction rate is formed with a chemical sensitizer, this effect can be enhanced. Therefore, it is preferable to use a good chemical sensitizer. When the redox compound is used, the edge of the image is sharpened, so that the particle interval can be narrowed and the resistance of the silver metal wire can be lowered.

  The redox compound has hydroquinones, catechols, naphthohydroquinones, aminophenols, pyrazolidones, hydrazines, reductones, etc. as redox groups. A preferred redox compound is a compound having a -NHNH- group as a redox group, and a typical redox compound is represented by the following general formula.

T-NHNHCO-V- (Time) _n -PUG
T-NHNHCOCO-V- (Time) _n -PUG
In the formula, T and V represent a group having the same meaning as the hydrazine compound. PUG represents a photographically useful group such as 5-nitroindazole, 4-nitroindazole, 1-phenyltetrazole, 1- (3-sulfophenyl) tetrazole, 5-nitrobenztriazole, 4-nitrobenzotriazole, 5- Examples thereof include nitroimidazole and 4-nitroimidazole. These development-inhibiting compounds are directly added to the CO site of T-NHNH-CO- through a heteroatom such as N or S or represented by (Time), and further via an alkylene, phenylene, aralkylene, or aryl group. And S can be connected via a heteroatom. In addition, those obtained by introducing a development inhibiting group such as triazole, indazole, imidazole, thiazole, thiadiaol into a hydroquinone compound having a ballast group can be used.

  For example, 2- (dodecylethylene oxide) thiopropionic acid amide-5- (5-nitroindazol-2-yl) hydroquinone, 2- (stearylamide) -5- (1-phenyltetrazol-5-thio) hydroquinone, 2 -(2,4-di-t-amylphenopropionic acid amide) -5- (5-nitrotriazol-2-yl) hydroquinone, 2-dodecylthio-5- (2-mercaptothiothiadiazole-5-thio) hydroquinone, etc. Is mentioned. Note that n represents 1 or 0. The redox compound can be synthesized with reference to the description in US Pat. No. 4,269,929.

  Particularly preferred redox compounds are listed below.

(R-1): 1- (4-Nitroindazol-2-yl-carbonyl) -2-{[4- (3-n-butylureido) phenyl]} hydrazine (R-2): 1- (5- Nitroindazol-2-yl-carbonyl) -2- {4- [2- (2,4-di-tertpentylphenoxy) butyramide] phenyl} hydrazine (R-3): 1- (4-nitrotriazole-2- Yl-carbonyl) -2- {4- [2- (2,4-di-tert-pentylphenoxy) butyramide] phenyl} hydrazine (R-4): 1- (4-nitroimidazol-2-yl-carbonyl) -2- {4- [2- (2,4-di-t-pentylphenoxy) butyramide] phenylsulfonamidophenyl} hydrazine (R-5): 1- (1-sulfophenyltetrazo 4-methyloxazole) -2- {3- [1-phenyl-1′-p-chlorophenylmethanethioglycinamidophenyl] sulfonamidophenyl} hydrazine (R-6): 1- (4-nitroindazole- 2-yl-carbonyl) -2-{[4- (octyl-tetraethylene oxide) -thio-glycinamidophenyl-sulfonamidophenyl]} hydrazine.

Hydrazine compounds, amine compounds, pyridinium compounds, tetrazolium compounds and redox compounds preferably contain 1 × 10 ^-6 ~5 × 10 ^-2 mol per mol of silver halide, in particular 1 × 10 ^-4 ~2 × 10 ^{- Two} moles are preferred. It is easy to adjust the addition degree of these compounds to increase the degree of contrast γ to 6 or more. γ can be further adjusted by monodispersity of the emulsion, the amount of rhodium used, chemical sensitization, and the like. Here, γ is a density difference with respect to a difference between exposure amounts giving density of 0.1 and 3.0.

  These compounds are used by being added to a layer containing halogenated particles or another hydrophilic colloid layer. If it is water-soluble, it is added to an aqueous solution. If water-insoluble, it is added to a silver halide grain solution or hydrophilic colloid solution as a solution of an organic solvent miscible with water, such as alcohols, esters, and ketones. That's fine. Moreover, when it does not melt | dissolve in these organic solvents, it can add with a ball mill, a sand mill, a jet mill, etc. and it can be made into 0.01-10 micrometers microparticles | fine-particles. As the fine particle dispersion method, a technique of solid dispersion of a dye as a photographic additive can be preferably applied. For example, a desired particle size can be obtained using a dispersing machine such as a ball mill, a planetary rotating ball mill, a vibrating ball mill, or a jet mill. When a surfactant is used at the time of dispersion, stability after dispersion can be improved.

  In the silver halide grain-containing layer according to the present invention, the silver halide grains are uniformly dispersed, and the silver halide grains are supported on the support to ensure adhesion between the silver halide grain-containing layer and the support. A binder can be used for the purpose.

  The binder that can be used in the present invention is not particularly limited, and both a water-insoluble polymer and a water-soluble polymer can be used, but a water-soluble polymer is preferably used from the viewpoint of improving developability. In the present invention, it is advantageous to use gelatin as a binder, but if necessary, gelatin derivatives, graft polymers of gelatin and other polymers, proteins other than gelatin, sugar derivatives, cellulose derivatives, single or co-polymerized A hydrophilic colloid such as a synthetic hydrophilic polymer such as a coalescent can also be used. There is no restriction | limiting in particular in the amount of binders in a silver halide grain content layer, The optimal value can be used from an applicability | paintability, a film physical property, electromagnetic wave shielding performance, etc.

  From the viewpoint of forming a developed silver network and increasing the conductivity of the film after development, in the present invention, it is preferable to set the Ag / binder volume ratio higher than that of a normal photographic silver halide photographic material. The binder content in the particle-containing layer is preferably 0.2 to 100 in terms of Ag / binder volume ratio, more preferably 0.3 to 30, and still more preferably 0.3 to 10. .

  In the present invention, a layer containing a near infrared absorbing dye is provided for the purpose of shielding near infrared rays. This near-infrared absorbing dye is a gelatin aqueous solution especially with fine particles of water-dispersible thermoplastic resin or phosphate ester, in order to enhance its near-infrared shielding effect, enhance dispersion or dissolution stability, and enhance stability over time. It has been found that it is preferable to disperse in it.

  The water-dispersible thermoplastic resin used in the present invention is a thermoplastic resin that is coated on a support and is thermoplastic at a drying temperature so that a film can be formed by heating and drying. The drying temperature is usually between room temperature and about 100 ° C., and drying is performed at a temperature in this range.

  The water-dispersible thermoplastic resin used in the present invention is treated as a synonym for latex because it handles a resin that is stably dispersed in an aqueous medium. Latex refers to white milky sap collected from rubber trees, etc., but since the emergence of emulsion polymers, polymeric substances including aqueous dispersions of synthetic polymers have stabilized in aqueous media. This name is used because what has been dispersed is called latex.

  Examples of the water-dispersible thermoplastic resin include polyvinylidene chloride, vinylidene chloride-acrylic acid copolymer, vinylidene chloride-itaconic acid copolymer, sodium polyacrylate, polyethylene oxide, acrylic acid amide-acrylic acid ester copolymer Monomers, styrene-maleic anhydride copolymers, acrylonitrile-butadiene copolymers, vinyl chloride-vinyl acetate copolymers, and monomers containing carboxylic acid groups such as acrylic acid, methacrylic acid, itaconic acid and maleic acid in some cases Alternatively, a styrene-butadiene copolymer, a styrene-isoprene copolymer, or the like using a small amount of one or a plurality of monomers having a sulfonic acid group such as dimethylacrylamide propane sulfonic acid or styrene sulfonic acid group may be used.

  The latex is widely used as a binder for aqueous coating, and among them, a latex that improves water resistance is preferable as a binder. The amount of latex used for obtaining water resistance as a binder is determined in consideration of applicability, but the amount used is preferably as high as possible from the viewpoint of moisture resistance, and is 50% or more and 100% or less based on the total mass of the binder. Is preferable, and 80% or more and 100% or less is more preferable. Such resins can also be obtained from the market.

  For example, styrene resin is an industry standard product number of styrene-butadiene copolymer, and various brands such as # 1500, # 1502, # 1507, # 1712, # 1778, Sumitomo SBR latex (Sumitomo Chemical Co., Ltd.) and JSR latex ( Nippon Synthetic Rubber Co., Ltd.) or Nipol Latex (Nippon Zeon Co., Ltd.) can be used. The styrene-butadiene copolymer has a copolymerization ratio (mass) of styrene and butadiene of 10/90 to 90/10, more preferably 20/80 to 60/40. A high styrene latex having a ratio of 60/40 to 90/10 is used by mixing with a resin having a low styrene content (10/90 to 30/70), so that the scratch resistance and physical strength of the photosensitive layer are used. It is preferable for increasing the ratio. The mixing ratio (mass) is preferably in the range of 20/80 to 80/20.

  As the high styrene latex, commercially available products such as JSR0051 and 0061 (above, trade names of Nippon Synthetic Rubber Co., Ltd.) and Nipol 2001, 2057, 2007 (trade names of Nippon Zeon Co., Ltd.) can be used. Examples of the latex having a low styrene content include conventional ones other than those listed as the high styrene latex, such as JSR # 1500, # 1502, # 1507, # 1712, and # 1778.

  Moreover, acrylic latex generally known as an acrylic resin, for example, Nipol AR31, AR32, or Hycar 4021 (all are trade names of Nippon Zeon Co., Ltd.) can be used.

  As the acrylic resin, a polymer or copolymer using the following acrylate monomer as a raw material can also be used. In the following, (meth) acryloyl group is used in the meaning of acryloyl group or methacryloyl group. Monomers having one (meth) acryloyl group in the molecule include aliphatic alcohol methacrylates such as methyl methacrylate, ethyl methacrylate and octyl methacrylate, and aliphatic alcohols such as methyl acrylate, ethyl acrylate, butyl acrylate and octyl acrylate. Acrylic acid esters, cyclohexyl acrylate, cyclohexyl methyl acrylate and other alicyclic alcohol acrylic esters, cyclohexyl methacrylate, cyclohexyl methyl methacrylate and other alicyclic alcohol methacrylic esters, phenyl acrylate, 4-promophenyl acrylate, benzyl acrylate , Acrylic acid ester containing an aromatic group such as benzyl methacrylate, phenyl methacrylate, 4- Le phenyl methacrylate, methacrylic acid ester containing an aromatic group such as benzyl methacrylate, 2-hydroxyethyl acrylate, hydroxyalkyl esters of acrylic acid or methacrylic acid such as 2-hydroxyethyl methacrylate.

  As monomers having two or more (meth) acryloyl groups in the molecule, acrylic acid diesters such as ethylene glycol diacrylate, propylene glycol diacrylate, diethylene glycol diacrylate, 1,3-diaacryloxy-2-propanol polyethylene glycol diacrylate, Methacrylic acid diesters such as ethylene glycol dimethacrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-dimethacryloxy-2-propanol, acrylic acid triesters such as glycerin triacrylate, trimethylolpropane triacrylate, Meta such as glycerin trimethacrylate, trimethylolpropane trimethacrylate There are acrylic acid tri-ester.

  As the styrene resin, methyl styrene monomers such as methyl styrene, ethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, octyl styrene, dimethyl styrene, trimethyl styrene, diethyl styrene, triethyl styrene, fluoro styrene, chloro A halogenated styrene monomer such as styrene, bromostyrene, iodostyrene or dibromostyrene, a nitrostyrene monomer, an acetylstyrene monomer, a methoxystyrene monomer, or the like is used alone or copolymerized with another monomer.

  The vinyl resin contains vinyl pyridine, vinyl pyrrolidone, vinyl carbazole, vinyl acetate, acrylonitrile, vinyl chloride, vinyl bromide, vinylidene chloride, vinylidene bromide, vinylidene, or the like as a structural unit as a monomer. Moreover, you may include the monomer which has a 2 or more vinyl group in a molecule | numerator as a structural unit. Examples thereof include conjugated diene monomers such as divinylbenzene, butadiene, and chloroprene, isoprene adipate divinyl, divinyl sulfone, triethylene glycol divinyl ether, 1,4-cyclohexanedimethanol divinyl ether, and the like.

  These monomers can be emulsion polymerized as described above. As the water-soluble polymerization initiator used in this emulsion polymerization, any one can be selected, and examples thereof include 2,2′-azobis (2-methylpropionamidine) dihydrochloride, 4,4′-azobis (4-cyano). Valeric acid), 2,2'-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) Propane] dihydrochloride, 2,2'-azobisisobutyramide dihydrate and the like. The amount of the water-soluble polymerization initiator used is preferably 0.001 to 0.5 mol% with respect to all monomers.

  Moreover, the dispersant used for the emulsion polymerization is appropriately used to stabilize the system. Examples of the dispersion stabilizer or dispersant include polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polymethacrylamide, hydroxyalkyl acrylate polymer, hydroxyalkyl methacrylate polymer, polyacrylic acid or salt thereof, polymethacrylic acid or salt thereof, and ethylene-acrylic acid. Copolymer or salt thereof, ethylene-methacrylic acid copolymer or salt thereof, ethylene-maleic acid copolymer or salt thereof, styrene-acrylic acid copolymer or salt thereof, styrene-methacrylic acid copolymer or salt thereof , Polyethyleneimine, polyalkylene glycol, polyalkylene oxide, methylolated polyamide, water-soluble melamine resin, water-soluble phenol resin, water-soluble urea resin, casein, gelatin, carboxymethylcellulose , Methyl cellulose, hydroxyalkyl cellulose, carboxymethyl starch, cationized starch, dextrin, alginic acid or salt thereof, carrageenan, gellan gum, locust bean gum, gum arabic, tragacanth gum, glucomannan, zalep mannan, guar gum, plant mucus, etc. A single substance or a mixture of two or more kinds is used.

  The dispersant is preferably used in an amount of 0.01 to 20% by mass based on the total amount of monomers used or the total amount of resin to be dispersed. Further, the surfactant used in the emulsion polymerization is not particularly limited as long as it does not adversely affect the polymerization reaction, and is an anionic surfactant, a cationic surfactant, an amphoteric surfactant or a nonionic surfactant. Either of these can be used.

  For example, sodium alkylbenzene sulfonate, higher alcohol sulfate sodium salt, higher α-olefin sulfonate sodium salt, higher fatty acid salt, higher alkylphenol alkylene oxide sodium sulfonate, higher alkyl amine salt, higher alkyl trimethyl ammonium salt, higher alkyl pyridinium salt Higher acylaminomethylpyridinium salt, higher acyloxymethylpyridinium salt, N, N-dipolyoxyethylene-N-higher alkylamine salt, higher alkylpolyethylenepolyamine salt, trimethyl higher alkylaniline sulfate, trimethyl higher alkylbenzylammonium salt, Higher alcohol ethylene oxide adduct, higher alkylphenol ethylene oxide adduct, higher fatty acid ethylene oxide addition Higher alkylamine ethylene oxide adducts, higher fatty acid amide ethylene oxide adducts, glycerin higher fatty acid esters, pentaerythritol higher fatty acid esters, higher fatty acid esters of sorbitol and sorbitan (or their ethylene oxide adducts), sucrose higher fatty acid esters, polyols Examples thereof include higher alkyl ethers, higher fatty acid amides of alkanolamines, amino acid type amphoteric activators, betaine type amphoteric activators and the like, or a mixture of two or more thereof.

  The surfactant is preferably used in an amount of 0.01 to 20% by mass based on the total amount of monomers used or the total amount of resin to be dispersed.

  The water-dispersible thermoplastic resin according to the present invention is preferably used together with gelatin at a mixing mass ratio of 1: 2 to 10: 1. By using in combination with gelatin, simultaneous coating with the silver halide grain-containing layer is possible, and productivity is remarkably improved. When the mass ratio of gelatin is large, the moisture resistance is greatly deteriorated, and when it is small, the coating is difficult to be uniform.

  When used with gelatin, a phosphate compound can be dispersed in fine particles in gelatin instead of the water-dispersible thermoplastic resin.

  In the method of dispersing the phosphoric acid ester compound in an average particle size of 10 nm to 10 μm, the phosphoric acid ester compound is dissolved in an ester organic solvent such as ethyl acetate, and a nonionic or anionic surfactant is added to the gelatin. Can be dispersed. As the nonionic or anionic surfactant used here, a surfactant of the type used for emulsion polymerization of a water-dispersible thermoplastic resin can be applied. In order to improve the dispersibility, a highly efficient homogenizer, ultrasonic dispersion, supersonic jet dispersion, or the like can be used to disperse as fine particles.

  Examples of the phosphoric ester compound include those obtained by esterifying phosphoric acid with an aliphatic alcohol, aromatic alcohol, or a mixed alcohol thereof, and condensed esters obtained by condensing two or more dialkyl or diaryl phosphoric esters. Specific examples include trioctyl phosphate ester, tridodecyl phosphate ester, triphenyl phosphate ester, tricresyl phosphate ester, tri p-methylphenyl phosphate ester, and the like.

  Specific examples of near-infrared absorbing dyes include polymethine, phthalocyanine, naphthalocyanine, metal complex, aminium, imonium, diimonium, anthraquinone, dithiol metal complex, naphthoquinone, indolephenol, azo And triallylmethane compounds.

  The PDP optical filter is required to have near-infrared absorptivity mainly for absorption of heat rays and noise prevention of electronic devices. For this purpose, a dye having a near-infrared absorbing ability having a maximum absorption wavelength of 750 to 1100 nm is preferable, and a metal complex, aminium, phthalocyanine, naphthalocyanine, diimonium, and squalium compound are particularly preferable.

  The absorption maximum of a conventionally known nickel dithiol complex compound or fluorinated phthalocyanine compound is 700 to 900 nm, and for practical use, an aminium compound usually having an absorption maximum in a longer wavelength region than the above compound. In particular, when used in combination with a diimmonium compound, an effective near infrared absorption effect can be obtained.

  Specific examples of imonium compounds that can be used in the present invention are shown below.

(I-1): N, N, N ′, N′-tetrakis (4-di-n-butylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-2): N, N, N ′, N′-tetrakis (4-di-n-butylaminophenyl) -1,4-benzoquinone-bis (imonium / perchloric acid)
(I-3): N, N, N ′, N′-tetrakis (4-di-amylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-4): N, N, N ′, N′-tetrakis (4-di-n-propylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-5): N, N, N ′, N′-tetrakis (4-di-n-hexylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-6): N, N, N ′, N′-tetrakis (4-di-iso-propylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-7): N, N, N ′, N′-tetrakis (4-di-n-pentylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid)
(I-8): N, N, N ′, N′-tetrakis (4-di-methylaminophenyl) -1,4-benzoquinone-bis (imonium hexafluoroantimonic acid).

  As a near-infrared absorbing dye in the present invention, diimonium compounds are IRG-022, IRG-040 (these are trade names manufactured by Nippon Kayaku Co., Ltd.), nickel dithiol complex compounds are SIR-128, SIR-130, SIR-132, SIR-159, SIR-152, SIR-162 (these are trade names manufactured by Mitsui Chemicals, Inc.), phthalocyanine compounds are IR-10, IR-12 (above, products manufactured by Nippon Shokubai Co., Ltd.) Name) etc. can be used.

  The near-infrared absorbing dye may be used after being dissolved in an organic solvent such as alcohol solvents such as methanol, ethanol and isopropanol, ketone solvents such as acetone, methyl ethyl ketone and methyl butyl ketone, dimethylsulfoxide, dimethylformamide, dimethyl ether and toluene. It is preferable to apply fine particles having an average particle diameter of 0.01 to 10 μm with a fine particle machine, and the addition amount is preferably in the range of 0.05 to 3.0 at the maximum wavelength of the optical density.

  In addition, when making the color correction layer contain the pigment | dye which has near-infrared absorptivity, you may contain any 1 type in said pigment | dye, and may contain 2 or more types. In order to avoid deterioration of the near-infrared absorbing dye due to ultraviolet rays, it is preferable to use an ultraviolet absorber.

  As the ultraviolet absorber, known ultraviolet absorbers such as salicylic acid compounds, benzophenone compounds, benzotriazole compounds, S-triazine compounds, cyclic imino ester compounds, and the like can be preferably used. Of these, benzophenone compounds, benzotriazole compounds, and cyclic imino ester compounds are preferred. As what is blended with the polyester, a cyclic imino ester compound is particularly preferable.

As a preferable specific example,
(U-1): 2- (2-hydroxy-3,5-di-α-cumyl) -2H-benzotriazole (U-2): 5-chloro-2- (2-hydroxy-3-t-butyl -5-methylphenyl) -2H-benzotriazole,
(U-3): 5-chloro-2- (2-hydroxy-3,5-di-t-butylphenyl) -2H-benzotriazole (U-4): 5-chloro-2- (2-hydroxy-) 3,5-di-α-cumylphenyl) -2H-benzotriazole (U-5): 5-chloro-2- (2-hydroxy-3-α-cumyl-5-t-octylphenyl) -2H-benzotriazole (U-6): 2- (3-tert-butyl-2-hydroxy-5- (2-isooctyloxycarbonylethyl) phenyl) -5-chloro-2H-benzotriazole (U-7): 5-tri Fluoromethyl-2- (2-hydroxy-3-α-cumyl-5-t-octylphenyl) -2H-benzotriazole (U-8): 5-trifluoromethyl-2- (2-hydroxy-5-t -Oct Phenyl) -2H-benzotriazole (U-9): 5-trifluoromethyl-2- (2-hydroxy-3,5-di-t-octylphenyl) -2H-benzotriazole (U-10): 5- Trifluoromethyl-2- (2-hydroxy-3-α-cumyl-5-t-butylphenyl) -2H-benzotriazole (U-11): 2,4-bis (4-biphenylyl) -6- ( 2-hydroxy-4-octyloxycarbonylethylideneoxyphenyl) -s-triazine (U-12): 2,4-bis (2,4-dimethylphenyl) -6- [2-hydroxy-4- (3-nonyloxy) * -2-Hydroxypropyloxy) -5-α-cumylphenyl] -s-triazine, (* is a mixture of octyloxy, nonyloxy and decyloxy groups) Show.)
(U-13): 2,4,6-tris (2-hydroxy-4-isooctyloxycarbonylisopropylideneoxyphenyl) -s-triazine (U-14): hydroxyphenyl-2H-benzotriazole (U-15) ): 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole (U-16): 2- (3,5-di-t-butyl-2-hydroxyphenyl) -2H-benzotriazole is there.

  In the method for producing an electromagnetic wave shielding film of the present invention, it is preferable to provide a layer containing photosensitive silver halide grains after providing a layer having a near infrared absorption function on a support. Or it is preferable to provide simultaneously the layer which has a near-infrared absorption function, and the layer containing a photosensitive silver halide grain on a support body.

  This is because the silver / binder volume ratio of the layer containing the photosensitive silver halide grains of the present invention is high, and the coating stability is low in the usual method, so low-speed coating is unavoidable. This is because it has been found that the coating stability of the layer containing the photosensitive silver halide grains is improved so that high-speed coating is possible.

  In addition, when a layer having a near-infrared absorption function and a layer containing photosensitive silver halide grains are laminated in a simultaneous multilayer system, even if the silver / binder volume ratio of the layer containing photosensitive silver halide grains is considerably high, high speed This is because it has been found that application is possible. Furthermore, if the support, the layer having a near-infrared absorbing function, and the layer containing photosensitive silver halide grains are close to each other or adjacent to each other, halation or irradiation when exposure is performed with a near-infrared laser beam or the like. Can be reduced, and a mesh pattern composed of sharper fine lines can be formed, which is preferable.

  In the present invention, as a support, for example, a cellulose ester film, a polyester film, a polycarbonate film, a polyarylate film, a polysulfone (including polyethersulfone) film, a polyester film such as polyethylene terephthalate, polyethylene naphthalate, etc. , Polyethylene film, polypropylene film, cellophane, cellulose diacetate film, cellulose acetate butyrate film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol film, syndiotactic polystyrene film, polycarbonate film, norbornene resin film, poly Methyl pentene film, polyether ketone film, polyether Ketone-imide film, a polyamide film, a fluororesin film, a nylon film, a polymethyl methacrylate film or an acrylic film or the like.

  Of these, cellulose triacetate film, polycarbonate film, polysulfone (including polyethersulfone) and polyethylene terephthalate film are preferably used.

  In the present invention, it is particularly preferable to use a cellulose ester film as the support from the viewpoints of transparency, isotropy, adhesion and the like.

  When the electromagnetic wave shielding film of the present invention is used for a display screen of a display, since high transparency is required, it is desirable that the support itself has high transparency. In this case, the average transmittance of the entire visible light region of the plastic film or glass plate is preferably 85 to 100%, more preferably 90 to 100%. In the present invention, as the color tone modifier, the plastic film or glass plate colored to the extent that the object of the present invention is not hindered can also be used.

  In the present invention, the average transmittance in the visible light region is 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, and obtaining the average value. It is defined as

  In the present invention, an embodiment in which the average transmittance in the visible light region is 85% or more is preferable, more preferably 88% or more, and still more preferably 90% or more.

  Although there is no restriction | limiting in particular in the thickness of the support body used for this invention, From a maintenance of the transmittance | permeability and a viewpoint of handleability, it is preferable that it is 5-200 micrometers, and it is still more preferable that it is 30-150 micrometers.

  Before applying a silver halide layer or the like to the support used in the present invention, it is preferable to subject the surface to hydrophilic treatment or to apply an undercoat layer or the like on various supports.

  As a method for applying the silver halide grain layer, the near-infrared absorbing dye layer, and the antireflection layer in the present invention, various methods are conventionally known. For example, dip coating method, blade coating method, air knife coating method, wire bar coating method, gravure coating method, reverse roll coating method, slot type coating method, slide hopper coating method, slot type curtain coating method, slide type curtain coating method Etc. are known. And in these coating methods, in order to obtain a uniform dry film thickness with high accuracy in the width direction of the substrate, pay attention to the coating film thickness accuracy and uniformity during coating (after coating and before drying), Applying.

  Among these coating methods, a coating apparatus having a flow rate regulation die is particularly capable of high-speed, thin-film, high-precision, multi-layer simultaneous coating, and photographic photosensitive material, inkjet recording material, magnetic recording material, etc. It is widely used as a coating device.

  In the present invention, it is preferable to use a coating apparatus having a flow rate regulation die. In particular, the slide hopper type coating device and the slide type curtain coating device can be applied simultaneously, and by applying the silver halide grain-containing layer and the near infrared absorbing dye-containing layer simultaneously, the productivity can be remarkably improved. It becomes possible.

  The anti-reflection layer is most suitable for the anti-reflection layer because simultaneous multi-layer coating is difficult as a coating liquid composition. The slot-type coating device is also a coating device having a die, and by using this method, high-precision coating is possible.

  In the case of a slide hopper coating device, the coating liquid sent to the die from the liquid feeding pump enters a liquid reservoir called a pocket spreading in the width direction, and from here a narrow slit so as to have a uniform thickness in the coating width direction. It is pushed out and flows down the slide surface, and a coating liquid reservoir called a bead is formed between the slide surface tip and the continuously running support, and coating is performed through this bead. By overlaying different liquids on the slide surface, simultaneous multi-layer coating can be performed. In order to stabilize the bead, a decompression chamber is provided below the bead and is maintained at a negative pressure so that the bead is stably formed.

  In the case of a slide type curtain applicator, the slide surface flows down with a uniform thickness in the coating width direction, and a curtain-like liquid film is formed between the edge guides provided at both ends of the slide surface. The falling curtain-like liquid film collides with the continuously running support to form a coating layer. In the case of a slide type curtain coating apparatus, simultaneous multilayer coating can be performed by superimposing different liquids on the slide surface.

  In the case of the slot type coating apparatus, the coating liquid extruded with a uniform film thickness in the width direction is pushed out from the slit, and a bead is formed directly with the traveling support, and coating is performed through this bead. Also in the case of the slot type coating apparatus, a decompression chamber is installed below the bead for stabilization of the bead as necessary.

  After coating by these coating apparatuses, the coating solution may be dried by various drying methods and then wound up or may be transported to the next process as it is.

  In the present invention, the silver halide grain-containing layer provided on the support is exposed to form a conductive pattern by development / reinforcement processing described later. Examples of the light source used for the exposure include light such as visible light and ultraviolet light, radiation such as electron beam and X-ray, and the like using ultraviolet light or near infrared light is preferable. Further, a light source having a wavelength distribution may be used for exposure, or a light source having a narrow wavelength distribution may be used.

  As the visible light, various light emitters that emit light in the spectral region are used as necessary. For example, one or more of a red light emitter, a green light emitter, and a blue light emitter are mixed and used. The spectral region is not limited to the above red, green, and blue, and phosphors that emit light in the yellow, orange, purple, or infrared region are also used. An ultraviolet lamp is also preferable, and g-line of a mercury lamp, i-line of a mercury lamp, etc. are also 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, F ₂ 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 a device that is particularly compact, quick, long-life, and highly stable, 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 method for exposing the silver halide grain-containing layer to an image may be performed by surface exposure using a photomask or by scanning exposure using a laser beam. At this time, either condensing exposure using a lens or reflection exposure using a reflecting mirror may be used, and exposure methods such as surface contact exposure, near field exposure, reduced projection exposure, and reflection projection exposure can be used. The laser output may be about several tens of μW to 5 W, as long as it is an amount suitable for exposing the silver halide.

  In the present invention, after the silver halide grain-containing layer is exposed, development processing is performed. 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.

  Further, sodium sulfite or potassium sulfite as a preservative, sodium carbonate or potassium carbonate as a buffering agent, 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 according to the present invention 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.

  In the present invention, the development process performed after exposure may include pre-fixing physical development. The term “physical development before fixing” as used herein refers to a process of reinforcing developed silver by supplying silver ions from outside the silver halide grains having a latent image by exposure before performing fixing processing described later. As a specific method for supplying silver ions from the developing solution, for example, a method in which silver ions or silver complex ions silver nitrate are dissolved in advance in the developing solution as described in physical development described later, or development A silver halide solvent such as sodium thiosulfate or ammonium thiocyanate is dissolved in the solution, and unexposed silver halide is dissolved during development to compensate for development of silver halide grains having a latent image. There is a method to force.

  In the present invention, it is preferable to use a formulation in which a silver halide solvent is dissolved in advance in a developing solution because a decrease in the transmittance of the film due to the occurrence of fogging in an unexposed portion can be suppressed.

  In the development processing in the present invention, after the black and white development of the exposed silver halide grains, fixing processing is performed for the purpose of removing and stabilizing the unexposed silver halide grains.

  In the fixing process of the present invention, the fixing solution used in a photographic film or photographic paper using silver halide grains can be used. The fixing solution used in the fixing process according to the present invention is sodium thiosulfate as a fixing agent. , Potassium thiosulfate, ammonium thiosulfate and the like can be used. As a hardening agent at the time of fixing, aluminum sulfate, chromium sulfate, or the like can be used. 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.

  The washing water used in the present invention includes N-methyl-isothiazol-3-one, N-methyl-isothiazol-5-chloro-3-one, and N-methyl-isothiazole-4,5 as antifungal agents. -Dichloro-3-one, 2-nitro-2-bromo-3-hydroxypropanol, 2-methyl-4-chlorophenol, hydrogen peroxide and the like can be used.

  In the present invention, in order to assist the contact between the developed silvers formed by the above-described development process, and to increase the conductivity, it is preferable to perform a reinforcement process. In the present invention, the intensifying process refers to a process in which a conductive substance source not contained in the silver halide light-sensitive material is supplied from the outside during the development process or after the process to increase the conductivity. Examples of such a method include physical development or plating treatment.

  Physical development is performed by immersing a light-sensitive material containing a silver halide emulsion having a latent image in a processing solution containing silver ions or silver complex ions and a reducing agent, as is well known in the photographic art. Can do.

  In the present invention, physical development is defined not only when the development start point of physical development is the latent image nucleus but also when developed silver is the physical development start point, and this can be preferably used.

  In the present invention, various conventionally known plating methods can be used for the plating treatment used as the intensifying treatment. For example, electrolytic plating and electroless plating can be performed alone or in combination. Among them, electrolytic plating excellent in selectivity of plating metal, adjustment of plating speed, and plating strength can be preferably used in the present invention. Electroless plating has the advantage that uneven plating due to uneven current distribution does not occur. As a metal that can be used for plating, for example, copper, nickel, cobalt, tin, silver, gold, platinum, and other various alloys can be used. It is particularly preferable to use copper electrolytic plating from the viewpoint that the plating process is relatively easy and high conductivity is easily obtained.

  The intensifying process can be performed at any timing during development, after development, before fixing, and after fixing process. However, from the viewpoint of maintaining high transparency of the film, an embodiment in which it is performed after the fixing process is preferable.

  In the present invention, it is preferable to carry out an oxidation treatment after the development treatment or the intensification treatment. By the oxidation treatment, unnecessary metal components can be ionized and dissolved and removed, and the transmittance of the film can be further increased.

  In the present invention, a mode in which a conductive mesh pattern is formed by drawing a lattice-like fine line pattern by exposure and then performing development processing or the like in order to impart high translucency and high electromagnetic wave shielding performance is preferable. The conductive metal part preferably has a line width of 20 μm or less and a line interval of 50 μm or more. In addition, the conductive metal portion may have a portion whose line width is larger 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 part is preferably less than 18 μm, more preferably less than 15 μm, further preferably less than 14 μm, and less than 10 μm. Is more preferred, most preferably less than 7 μm. Moreover, 0.05-30 micrometers is preferable, as for the thickness of a line | wire, 0.1-20 micrometers is more preferable, and 0.1-10 micrometers is especially preferable.

  In the present invention, in order to provide high translucency and high electromagnetic wave shielding performance, the visible light transmittance of the portion without the fine lines of the lattice-like mesh pattern is preferably 70% or more, more preferably 80% or more, and 90%. The above is particularly preferable. In measurement, the measurement aperture needs to be sufficiently larger than the mesh pattern pitch described above, and is preferably obtained by measuring at least 100 times larger than the mesh area of the mesh.

  The conductive metal portion in the present invention has an aperture ratio of preferably 85% or more, more preferably 90% or more, and most preferably 95% or more from the viewpoint of visible light transmittance. The aperture ratio is the proportion of the entire portion of the mesh without fine lines. For example, the aperture ratio of a square grid mesh with a line width of 10 μm and a pitch of 200 μm is 90%. Further, the visible light transmittance of the opening (portion without a thin line) is preferably 80% or more, more preferably 90% or more, and particularly preferably 95% or more.

  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 10 g of gelatin per 100 g of silver in an aqueous medium and containing silver iodobromide grains (I = 2.5 mol%) having an average sphere equivalent diameter of 0.044 μm was prepared. At this time, the mass ratio of silver / gelatin was 10/1 (silver / gelatin volume ratio 1.3), and alkali-treated low molecular weight gelatin having an average molecular weight of 40,000 was used as the gelatin species.

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 performing gold sulfur sensitization using chloroauric acid and sodium thiosulfate, the following sensitizing dye SD-1 was added at 10 ^-4 mol per mol of silver halide. After spectral sensitization, hydrazine (H-2) and an accelerator amine compound (A-10) were added as a contrast-increasing agent.

The film was coated on a polyethylene terephthalate (PET) film that had been subjected to both-side undercoating using a slide hopper type coating apparatus so that the silver coating amount was 10 g / m ² (gelatin coating amount 1 g / m ² ).

<Exposure / development processing>
Using an image setter that gives a grid-like mesh pattern of line / space = 10 μm / 195 μm to the obtained sample 101, laser light having an oscillation wavelength of 440 nm (blue semiconductor laser diode manufactured by Nichia Corporation) ), And then developed for 60 seconds at 25 ° C. using the following developer, further fixed for 120 seconds at 25 ° C. using the following fixer, and then washed with water. It was. A mesh-like lattice pattern, which is a metal silver image, was formed on the obtained sample 101.

(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% W / V) 26.5 g
Water was added to 1 L and the pH was adjusted to 5.0.

  On the back side of the sample 101 on which the development-processed mesh-like metal lattice pattern was formed, a solution having the following composition was sequentially applied in a multilayer manner using a slot type coating device in the order of the middle refractive layer, the high refractive layer, and the low refractive layer. The coating thickness after drying of each layer was adjusted to 80 nm, 70 nm, and 95 nm in this order. In this way, an electromagnetic wave shielding film sample 101 having an antireflection layer was produced.

<< Preparation / application of antireflection layer >>
<Preparation of titanium dioxide dispersion>
Titanium dioxide (primary particle mass average particle diameter: 50 nm, refractive index: 2.70) 30 parts by mass, anionic diacrylate monomer (PM21, Nippon Kayaku Co., Ltd.) 4.5 parts by mass, cationic methacrylate monomer (DMAEA, manufactured by Kojin Co., Ltd.) 0.3 parts by mass and 65.2 parts by mass of methyl ethyl ketone were dispersed by a sand grinder to prepare a titanium dioxide dispersion.

(Preparation of coating solution for medium refractive index layer)
In 151.9 g of cyclohexanone and 37.0 g of methyl ethyl ketone, 0.14 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and 0.04 g of a photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) were dissolved. Further, 6.1 g of the above titanium dioxide dispersion and 2.4 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.) were added and stirred at room temperature for 30 minutes. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a medium refractive index layer.

(Preparation of coating solution for high refractive index layer)
In 1152.8 g of cyclohexanone and 37.2 g of methyl ethyl ketone, 0.06 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and 0.02 g of a photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) were dissolved. Furthermore, the ratio of the above titanium dioxide dispersion and the titanium dioxide dispersion of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.) is increased, and the refractive index of the high refractive index layer is increased. The amount was adjusted so as to be a ratio, and the mixture was stirred at room temperature for 30 minutes, and then filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
Silane coupling agent (KBM-503, Shin-Etsu Silicone Co., Ltd.) 3 g and 0.1 M / L hydrochloric acid 2 g were added to 200 g of methanol dispersion of silica fine particles with an average particle size of 15 nm (methanol silica sol, manufactured by Nissan Chemical Co., Ltd.). In addition, the mixture was stirred at room temperature for 5 hours and then allowed to stand at room temperature for 3 days to prepare a dispersion of silica fine particles treated with silane coupling. To 35.04 g of the dispersion, 58.35 g of isopropyl alcohol and 39.34 g of diacetone alcohol were added. Further, 1.02 g of photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and 0.51 g of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) in 772.85 g of isopropyl alcohol were added. Further, 25.6 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.) was added and dissolved. 67.23 g of the resulting solution was added to the above dispersion, a mixture of isopropyl alcohol and diacetone alcohol. The mixture was stirred for 20 minutes at room temperature and filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for a low refractive index layer.

  Next, as a comparative example, a sample 102 was produced in the application order opposite to that of the sample 101. That is, the antireflective layer is sequentially coated on a polyethylene terephthalate (PET) film that has been undercoated with a slot type coating device and dried, and then the silver halide grain-containing layer is placed on the opposite side of the support on a slide hopper Coating was performed using a mold coating device, and exposure and development processes were performed to form an electromagnetic wave shielding layer having a mesh-like metal lattice pattern. In this way, an electromagnetic wave shielding film sample 102 having an antireflection layer was produced.

<Evaluation>
Each sample produced by the above method was evaluated for the electromagnetic wave attenuation effect, transparency, and spot failure on the film surface by the following method.

(Electromagnetic wave attenuation effect)
After development, the silver image part is heated with an infrared pulsed semiconductor laser with a wavelength of 800 to 870 nm and an output of 50 W (Frankfurt, pulse width 10 msec), and the electromagnetic wave attenuation effect is measured by the electromagnetic wave shielding measurement method (KEC method) by the Kansai Electronics Industry Promotion Center. The electromagnetic wave attenuation effect was measured, and the electromagnetic wave attenuation effect (dB) at 100 MHz was compared.

(transparency)
For the transparency, a three-step evaluation was made by visual relative evaluation: good, slightly cloudy, and clearly cloudy.

(Spot failure)
The number of spot failures on the film surface as a product was evaluated by the visual number per 10 cm @ 2. Evaluation criteria were as follows.

◎: Extremely good 0 pieces ○: Good 1-2 pieces Δ: Practically acceptable level 3-4 pieces X: Unpractical level 5-8 pieces

(Evaluation of antireflection properties)
Specimens are placed horizontally on a desk, and a Paruk fluorescent lamp (3-wavelength emission type) is mounted on a 3m-high ceiling. Each set consists of two FL40SS / ELW / 37-type 37W units manufactured by Matsushita Electric Industrial Co., Ltd. 8 sets were arranged. The evaluator sat down on a desk chair and relatively evaluated the status of the fluorescent lamp reflected on the sample on the desk as follows.

○: Reflection of nearby fluorescent lamps is a little anxious, but I don't care about distances. △: I also care about reflections of distant fluorescent lamps.

(Coating speed limit)
When coating the silver halide grain-containing layer coating solution, the coating speed was changed, and the upper limit speed (m / min) at which coating unevenness (mainly step unevenness) occurred and the uniformity of the coated surface was impaired was examined.

(Other)
In addition, the findings found in the preparation of the sample are shown.

  A slight crack was observed in the antireflection layer of sample 102.

From the above results, in the production of the electromagnetic wave shielding film, by forming a mesh-shaped metal part and then coating and forming a layer having an antireflection function, the antireflection layer is excellent in transparency and spot failure is not a problem. It can be seen that this is an excellent production method with high antireflection properties and no occurrence of cracks.

In addition, as a result of measuring the charge amount of the support in the transport state immediately before applying the antireflection layer,
Compared with the sample 102, the sample 101 has a small charge amount, and it was found that the ground works effectively. It turns out that it is the outstanding manufacturing method which can reduce the load to a production process.

Example 2
<< Preparation of near-infrared absorbing dye coating liquid-1 >>
To a 0.5 L three-necked flask, add 300 g of deionized water, 25 g of methyl methacrylate (MMA), 25 g of styrene, 45 g of ethyl acrylate (EA), 5 g of hydroxyethyl methacrylate (HEMA), 250 mg of ammonium persulfate, and bubbling with nitrogen The mixture was stirred at 100 ° C. for 3 hours to obtain an acrylic resin (AC) aqueous dispersion. After completion of the reaction, 100 mg of hydroquinone was added to obtain a thermoplastic resin aqueous dispersion.

  To this dispersion, an immonium-based near-infrared absorbing dye (I-2) finely dispersed in a solid particle of 100 nm or less is added. After stirring for 1 hour, a 2% by weight aqueous gelatin solution is further added, and a near-infrared absorbing dye coating solution It was set to -1.

  The near-infrared absorbing dye was dispersed with a planetary ball mill (partially stabilized zirconia) manufactured by Ito. 100 ml of water, 10 g of near-infrared absorbing dye (I-2) and beads (5 mm diameter) were operated in 30 ml at room temperature in a 200 ml container to prepare a dispersion liquid having an average particle diameter of 100 nm.

<< Preparation of near-infrared absorbing dye coating liquid-2 >>
Phosphate ester-gelatin dispersion was 0.2 g of 4 g of tricresyl phosphate ester, 50 ml of ethyl acetate, and a surfactant (condensate of lauryl alcohol and a polyethylene glycol having a polymerization degree of 10) in 50 ml of an aqueous gelatin solution (4% by mass). Added and ultrasonically dispersed. To this dispersion, an immonium-based near-infrared absorbing dye (I-2) in which fine solid particles were dispersed to 100 nm or less was added to obtain a near-infrared absorbing dye coating solution-2.

  The near-infrared absorbing dye was dispersed in the same manner as the preparation of the near-infrared absorbing dye coating liquid-1.

As the support, the same undercoated polyethylene terephthalate film as used in Example 1 was used, and the amount of imonium-based near infrared dye (I-2) was 0.1 g / m ² , so that the near infrared absorbing dye was used. Coating liquids 1 and 2 were applied using a slide hopper type coating device, respectively, to obtain samples 201 and 202.

On the near-infrared absorbing layer of Samples 201 and 202, the same silver halide particle-containing coating solution as in Example 1 was applied so that the silver coating amount was 10 g / m ² (gelatin coating amount 1 g / m ² ). .

  Next, the near-infrared absorbing dye coating liquids 1 and 2 and the same silver halide particle-containing coating liquid as in Example 1 were mixed using a slide hopper type coating apparatus, the lower layer being a near-infrared absorbing dye layer and the upper layer being a halogen. Samples 203 and 204 were prepared by simultaneous multilayer coating so as to form a silver halide grain-containing layer.

  Samples 201 to 204 were exposed and developed in the same manner as in Example 1 to form a mesh-like metal lattice pattern. And the coating liquid of the antireflection layer was prepared by the same method as Example 1, and it apply | coated with the same application amount as Example 1 on the back surface side of the support body.

On the same undercoated polyethylene terephthalate film as in Example 1, the same silver halide particle-containing coating solution as in Example 1 was applied so that the silver coating amount was 10 g / m ² (gelatin coating amount 1 g / m ² ). After coating and exposing and developing in the same manner as in Example 1 to form a mesh-like metal lattice pattern, the near-infrared absorbing dye coating liquids 1 and 2 were respectively coated thereon, and samples 205 and 206 were applied. Was made. And the coating liquid of the antireflection layer was prepared by the same method as Example 1, and it apply | coated with the same application amount as Example 1 on the back surface side of the support body.

<Evaluation>
Each sample produced by the above method was evaluated in the same manner as in Example 1.

(Near infrared dye layer stability over time)
Evaluation of stability over time was carried out for 200 hours under the condition of a temperature of 70 ° C. and a relative humidity of 90%, and displayed as a percentage of deterioration of the absorption maximum. Table 2 shows the contents of the fabricated samples and the evaluated performance results. In the light resistance deterioration test, Super Xenon Weather Meter SX75 manufactured by Suga Test Instruments Co., Ltd. was used, and the relative humidity was 50%, the irradiation intensity was 50 W / m ² , and the rate of absorption deterioration after 100 hours test was evaluated. The smaller the value, the higher the stability and the better.

(Other)
In addition, the findings found in the preparation of the sample are shown.

  In samples 205 and 206, coating unevenness of the near-infrared absorbing dye-containing layer slightly occurred. It is inferred that this is due to the unevenness of the mesh pattern in the lower layer.

  From the above results, in the production of an electromagnetic wave shielding film, after providing a layer having a near infrared absorption function, a layer containing photosensitive silver halide grains is provided, or a layer having a near infrared absorption function and a photosensitive silver halide By providing a layer containing particles by simultaneous multi-layer coating, not only the electromagnetic wave attenuation effect, transparency of the antireflection layer and spot failure, but also high-speed coating is possible, and the near-infrared dye layer is also stable over time. It is high and it turns out that it is an outstanding manufacturing method without the problem in the applicability | paintability of a near-infrared dye layer.

Example 3
A gelatin aqueous solution was added to the silver halide grain-containing coating solution in Samples 203 and 204 of Example 2, and the silver coating amount was 1.0 g / m ² and the gelatin coating amount was 0.2 g / m ² (silver / gelatin). Samples 301 and 302 were produced in the same manner except that the volume ratio was 0.64).

After performing exposure and development processing in the same manner as in Example 1, continuous physical development was performed at 25 ° C. for 5 minutes with the following physical developer, followed by washing with water. Then, the following copper plating solution was subjected to electrolytic plating at 2.5 A / cm ² at 25 ° C. for 5 minutes and washed with water.

(Physical developer)
800ml of pure water
Citric acid 5g
Hydroquinone 7g
Silver nitrate 3g
Add water to bring the total volume to 1 liter.

(Copper plating solution)
125 g of copper sulfate
85 g of sulfuric acid
Polyethylene glycol 0.1g
1M hydrochloric acid 2.0ml
Add water to bring the total volume to 1 liter.

  After drying, in the same manner as in Example 1, the antireflection layer was applied to the back side of the support in the same amount as in Example 1.

  As a result of performing the same evaluation as in Examples 1 and 2, samples 301 and 302 subjected to intensifying treatment such as physical development and plating are excellent electromagnetic shielding films satisfying all the evaluation items. It can be seen that the manufacturing method is excellent.

Example 4
The sample was the same except that the sensitizing dye (SD-1) in the silver halide grains in the sample 101 of Example 1 and the sample 301 of Example 3 was replaced with a near-infrared sensitizing dye (S-1). 401 and 402 were created. In the exposure, an electromagnetic wave shielding film was produced in the same manner except that near-infrared semiconductor laser light having an oscillation wavelength of 810 nm was used.

  When the metal mesh was examined with an electron microscope, sharp thin lines were reproduced in the sample 402. From this, the silver halide grains are near-infrared sensitized and show near-infrared sensitivity, and an electromagnetic wave shielding film original plate having a near-infrared absorbing dye layer in the near layer is formed with a mesh pattern with near-infrared laser light. It was found that when exposed, a particularly excellent electromagnetic shielding film can be produced.

Claims (9)

An electromagnetic wave shielding film master having a layer containing photosensitive silver halide grains on a support is exposed to light and developed to form a mesh-like metal portion, and then a layer having an antireflection function is formed by coating. The manufacturing method of the electromagnetic wave shielding film characterized by the above-mentioned. The method for producing an electromagnetic wave shielding film according to claim 1, wherein the layer having an antireflection function is formed by coating on the back side of the support having a layer having a mesh-like metal part. The method for producing an electromagnetic wave shielding film according to claim 1 or 2, wherein the layer having an antireflection function comprises a plurality of light-transmitting layers containing inorganic fine particles and having different refractive indexes. 4. The layer according to any one of claims 1 to 3, wherein the layer containing the photosensitive silver halide grains is provided after providing a layer having a near-infrared absorbing function on a support. The manufacturing method of the electromagnetic wave shielding film of description. The electromagnetic wave according to any one of claims 1 to 4, wherein the layer containing the photosensitive silver halide grains is provided simultaneously with the layer having a near-infrared absorbing function on the support. Manufacturing method of shielding film. 5. The method according to claim 4, wherein the layer containing the photosensitive silver halide grains and the layer having a near-infrared absorbing function are formed by simultaneous multilayer coating by a slide hopper type coating device or a slide type curtain coating device. The manufacturing method of the electromagnetic wave shielding film of Claim 5. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 6, wherein the layer having an antireflection function is formed by successive multilayer coating using a slot type coating device. A metal having a mesh-like electromagnetic wave shielding function by subjecting the original plate for an electromagnetic wave shielding film provided with a layer containing photosensitive silver halide grains to exposure and development treatment, and further physical development treatment and / or plating treatment. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 7, wherein after the layer is formed, a layer having an antireflection function is applied and formed. An electromagnetic wave shielding film produced by the method for producing an electromagnetic wave shielding film according to any one of claims 1 to 8.