JP4957376B2 - Photosensitive material for forming transparent conductive film, transparent conductive film using the same, method for producing the same, and electromagnetic shielding material - Google Patents

Description

  The present invention relates to a transparent conductive film for forming a conductive material that can block electromagnetic waves generated from electronic devices such as mobile phones, microwave ovens, CRTs, and flat panel displays and that requires transparency. The present invention relates to a forming photosensitive material, a transparent conductive film, a manufacturing method thereof, and an electromagnetic wave shielding material.

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

  In order to shield the electromagnetic wave, the property of not allowing the metal electromagnetic wave to penetrate may be used. For example, there are a method of making the casing a metal body or a high conductor, a method of inserting a metal plate between circuit boards, and a method of covering a cable with a metal foil. However, in CRT, PDP, etc., an observer needs to recognize characters and the like displayed on the screen, and transparency (translucency) is required.

  In particular, a plasma display panel (PDP) generates a large amount of electromagnetic waves as compared with a CRT or the like and requires a strong electromagnetic shielding ability. Therefore, a translucent electromagnetic shielding material for PDP is required to have extremely high conductivity. .

  Further, high transparency of 70% or more is required as a required level for transparency and 80% or more for PDP is desired.

  For example, for materials and methods that achieve both electromagnetic shielding properties and transparency of the conductive mesh pattern, various materials and methods have been proposed so far in order to solve the above problems. A method in which an electroless plating catalyst is printed in a grid pattern by a printing method, and then electroless plating is performed (for example, see Patent Documents 1 and 2). For example, a photoresist containing an electroless plating catalyst is applied. There has been proposed a method of performing electroless plating after forming a pattern of an electroless plating catalyst by performing exposure and development (for example, see Patent Document 3).

  Furthermore, a method of forming a metal thin film mesh on a transparent substrate by etching using a metal thin film photolithography method has been proposed (see, for example, Patent Documents 4 to 7).

  However, in electroless plating by printing, the line width is large and a dense pattern is difficult, and the combination of electroless plating and photoresist allows fine processing and can create a mesh with high aperture ratio, thus shielding electromagnetic waves. However, it is known that transparency is insufficient, expensive palladium needs to be used, the process is complicated and complicated, and the production cost is high.

  Apart from these, there is known a method of forming a metal silver thin film pattern by a silver salt diffusion transfer method utilizing the fact that a metal silver (conductive) pattern can be easily formed by a silver salt photosensitive material. In addition, the silver salt-containing layer is exposed, developed, and after forming a metallic silver portion and a light-transmitting portion, by carrying out physical development and / or plating treatment, conductive metal particles are supported on the metallic silver portion, It has been disclosed to obtain an electromagnetic shielding film that satisfies both high conductivity and translucency (see, for example, Patent Document 8).

The printing method and silver salt method are attracting attention as a method that replaces the etching method in terms of production cost, but because the mesh pattern is additive type (creates a mesh pattern on the substrate), the mesh pattern and the substrate There was a problem in adhesion. For example, in the case of PDP, a translucent electromagnetic wave shielding material is circulated by being bonded to a protective film, and finally bonded to an antireflection film and a near infrared absorption film, and is combined and used as an optical filter. When the protective film is peeled off and bonded to form a composite, if the adhesion is poor, the mesh pattern is peeled off from the base material, which causes a problem because it does not function as an electromagnetic shielding material.
JP 11-170420 A Japanese Patent Laid-Open No. 5-288989 JP-A-11-170421 JP 2003-46293 A Japanese Patent Laid-Open No. 2003-23290 Japanese Patent Laid-Open No. 5-16281 JP-A-10-338848 JP 2004-221564 A

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a transparent conductive film having high conductivity and light transmission, reduced interference unevenness and moire, a method for manufacturing the same, and the transparent conductive film It is an object to provide an electromagnetic wave shielding material using a transparent conductive film-forming photosensitive material, a transparent conductive film, a method for producing the same, and an electromagnetic wave shielding material that are used in the production of the transparent conductive film.

  The above object of the present invention can be achieved by the following configuration.

1. A transparent conductive film having an emulsion layer comprising at least silver halide and a binder on a support and capable of producing a transparent conductive film by forming a metallic silver portion in a mesh shape by developing after exposure. A photosensitive material for formation, wherein the swelling ratio of the emulsion layer is hardened with a hardener to be greater than 100% and less than or equal to 145% , and the binder is a hydrophilic polymer mainly composed of gelatin, A photosensitive material for forming a transparent conductive film, wherein the amount of polyvalent metal ions in gelatin is more than 0 ppm and 500 ppm or less .

2. The silver halide coating silver amount is 0.1 to 1 g / m ² and the thickness of the emulsion layer of the non-mesh portion (light transmissive portion) of the transparent conductive film in which the metallic silver portion is formed in the mesh shape is 2. The photosensitive material for forming a transparent conductive film according to 1 above, which has a thickness of 0.05 to 0.2 μm.

3. 3. The transparent conductive film-forming photosensitive material as described in 1 or 2 above, wherein the emulsion layer is hardened with 150 to 500 mg of a hardener per 1 g of all binders present on the same side.

4). 4. The photosensitive material for forming a transparent conductive film according to 3 above, wherein the hardener contained in the emulsion layer is at least one triazine derivative.

5. The support is a support in which at least one easy-adhesion layer is coated adjacently, the refractive index of the support is greater than that of the easy-adhesion layer, and the difference in refractive index between the support and the easy-adhesion layer 5. The photosensitive material for forming a transparent conductive film according to any one of 1 to 4 , wherein the photosensitive material is within 0.1.

6). The transparent conductive film-forming photosensitive material according to any one of 1 to 5 above is exposed, developed, and further subjected to intensification to form a metallic silver portion in a mesh shape. A method for producing a transparent conductive film.

7). A transparent conductive film obtained by the production method described in 6 above.

8). 8. An electromagnetic wave shielding material using the transparent conductive film described in 7 above.

  According to the present invention, a transparent conductive film having high conductivity and light transmissivity and having reduced interference unevenness and moire, a manufacturing method thereof, an electromagnetic wave shielding material using the transparent conductive film, and the transparent conductive film Provided are a photosensitive material for forming a transparent conductive film, a transparent conductive film, a method for producing the same, and an electromagnetic wave shielding material having good adhesion used in the production.

  As a result of intensive studies in view of the above problems, the present inventors have obtained an emulsion of a light-sensitive material used for obtaining a transparent conductive film having high conductivity and light transmission and reduced moire. By making the layer (which becomes a transparent conductive film after development) extremely thin, the light transmittance of the non-mesh part (light transmissive part) can be improved, and the moire can be reduced because the height of the mesh part is low. I understood. Regarding conductivity, it is necessary to reduce the electric resistance value of developed silver, and it is effective to increase the density of silver halide grains by reducing binders such as gelatin from the emulsion layer. However, in this method, the retainability of the formed mesh line is deteriorated, resulting in poor adhesion. As a result of further studies, the present inventors have found that the adhesive layer and the conductivity can be compatible by setting the swelling ratio of the emulsion layer to 145% or less, and as soon as the present invention has been achieved.

  Hereinafter, the present invention will be described in detail.

<Support>
In the photosensitive material for forming a transparent conductive film of the present invention (hereinafter also simply referred to as a photosensitive material), a plastic film, a plastic plate, glass or the like can be used as a support. Examples of raw materials for plastic films and plastic plates include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), vinyl resins such as polyethylene (PE), polypropylene (PP), and polystyrene, and polycarbonate (PC). Triacetyl cellulose (TAC) or the like can be used.

  From the viewpoint of transparency, heat resistance, ease of handling, and price, the plastic film is preferably PET, PEN, or TAC.

  Since the electromagnetic wave shielding material for a display requires transparency, it is desirable that the support has high transparency. In this case, the total visible light transmittance of the plastic film or plastic plate is preferably 70 to 100%, more preferably 80 to 100%, and further preferably 90 to 100%. Moreover, in this invention, what colored the said plastic film and the plastic board to the extent which does not interfere with the objective of this invention can also be used as a color tone regulator.

<Emulsion layer>
In the light-sensitive material of the present invention, an emulsion layer containing silver halide is provided on a support as an optical sensor. The emulsion layer can contain a binder, a solvent and the like in addition to silver halide.

<Silver halide>
As the silver halide used in the present invention, the techniques conventionally used in various silver halide photographic light-sensitive materials can be used as they are in the present invention.

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

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

  For silver halide grains, from the viewpoint of image quality of the patterned metallic silver layer formed after exposure and development, the average grain size is preferably 0.1 to 1000 nm (1 μm) in terms of sphere equivalent diameter. The thickness is more preferably 0.1 to 100 nm, and further preferably 1 to 50 nm. The sphere equivalent diameter of silver halide grains is the diameter of grains having the same volume and having a spherical shape.

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

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

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

  In the present invention, in order to further improve the sensitivity as an optical sensor, chemical sensitization performed with a silver halide grain photographic emulsion can be performed. As chemical sensitization, gold sensitization, noble metal sensitization such as palladium, chalcogen sensitization such as sulfur, selenium and tellurium, reduction sensitization, and the like can be used.

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

<binder>
In the silver salt-containing layer according to the present invention, the binder (resin) can be used for the purpose of uniformly dispersing the silver salt particles and assisting the adhesion between the silver salt-containing layer and the support. The binder used in the present invention is most preferably gelatin. Examples of gelatin include lime-processed gelatin, acid-processed gelatin, and various modified gelatins such as phthalated gelatin and phenylcarbamoylated gelatin.

Gelatin generally contains divalent or higher polyvalent metal ions such as Fe, Mn, Cu, Zn, Mg, Ca as impurities, far exceeding 1000 ppm. The gelatin used for preparing the silver halide emulsion layer in the present invention is preferably purified so that these polyvalent metal ions are 500 ppm or less. The reason is not clear, but by reducing the polyvalent metal ion concentration, unevenness of plating generated in the intensification process, particularly in the plating process can be reduced, and the uniformity is improved. As a result, the conductivity is improved and contamination of the non-mesh part (light transmissive part) can be prevented. Such gelatin can be obtained by deionization such as ion exchange. For example, the content of the metal ions can be lowered by heating an aqueous gelatin solution and bringing it into contact with an ion exchange resin with stirring. Since metal elements in gelatin are usually cations, they can be removed by using H + type cation exchange resin, but negative complex salts are formed in metal elements. since it may, in such a case OH ^- can be removed by using a mold anion exchange resin. About these methods, the Chemical Society of Japan "Experimental Chemistry Course 2, Basic Technology II" Maruzen (1956), pages 151-202, the Chemical Society of Japan "New Experimental Chemistry Course 1, Basic Operation 1" Maruzen (1975), It is described in detail on pages 463-497. Determination of the content of polyvalent metal ions such as calcium ions in gelatin after ion exchange treatment may be carried out in accordance with the method described in the Gelatin Test Method for Photo (Abbreviation Baguy Method) established by the Joint Committee of Gelatin Test Method, 6th edition. .

  Content of the binder contained in the silver salt content layer concerning this invention is not specifically limited, It can determine suitably in the range which can exhibit a dispersibility and adhesiveness. The content of the binder in the silver salt-containing layer is preferably 1: 5 to 5: 1 in terms of Ag: binder volume ratio, more preferably 1: 3 to 3: 1, and 1: 2 to 2. More preferably, the ratio is 1. If the silver salt-containing layer contains a binder in an Ag: binder volume ratio of 1/4 or more, the metal particles can easily come into contact with each other in the physical development and / or plating process, and high conductivity can be obtained. Therefore, it is preferable. If the Ag: binder volume ratio of silver is 5 times or more, there are problems such as aggregation of silver halide grains, significant deterioration of coating properties, and cracking after drying due to insufficient binder.

<Hardener>
The emulsion layer of the photosensitive material for forming a transparent conductive film according to the present invention is preferably hardened with a hardener. As the hardener, known agents can be used, and vinylsulfone type hardeners and triazine type hardeners described in JP-A-61-249045 and JP-A-61-245153 can be used alone or in combination. However, in the present invention, the film is particularly preferably hardened with at least one triazine type hardener.

  Although there is no restriction | limiting in particular as a triazine type hardener used by this invention, It is preferable that it is a compound represented by the following general formula [HI] or [HI].

In the general formula [HI], R ¹ represents a chlorine atom, a hydroxy group, an alkyl group, an alkoxy group, an alkylthio group, -OM (M represents a monovalent metal atom), -NR'R "or -NHCOR. ″ ′ (R ′, R ″, R ″ ′ each represents a hydrogen atom, an alkyl group or an aryl group), and R ² has the same meaning as R ¹ except for a chlorine atom.

  As the alkyl group of the general formula [HI], the alkyl group of the alkoxy group and the alkylthio group is preferably a lower alkyl group having 1 to 5 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group. And these may further have a substituent. Examples of the aryl group include a phenyl group and a naphthyl group, which may further have a substituent. M is, for example, a sodium atom or a potassium atom.

In the general formula [H-II], R ³ and R ⁴ each represent a chlorine atom, a hydroxy group, an alkyl group, an alkoxy group, or —OM (M represents a monovalent metal atom), —Q— and — Q′— represents a linking group of —O—, —S— or —NH—, L represents an alkylene group or an arylene group, and m1 and n1 each represents 0 or 1.

  As the alkyl group of the general formula [H-II], an alkoxy group and an alkylthio group, a lower alkyl group having 1 to 5 carbon atoms is preferable, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group. And these may further have a substituent. The alkylene group is preferably one having 1 to 8 carbon atoms, for example, an ethylene group, a propylene group, a trimethylene group, a hexamethylene group or the like, and the arylene group is preferably an o-phenylene group, m- A phenylene group, a p-phenylene group, a 1,4-naphthalene group, and the like.

  Hereinafter, although the specific example of a triazine type hardener is shown, this invention is not limited to these.

  The amount of the hardener added depends on the total amount of binder on the same side of the photosensitive material for forming a transparent conductive film including the emulsion layer, and the swelling rate described below is greater than 100% and less than 145%. It is preferable to add. The preferable addition amount of the hardener contained in the transparent conductive film-forming photosensitive material of the present invention is preferably 150 mg or more, more preferably 200 mg or more and 500 mm or less, per 1 g of all binders on the same side.

[Swelling rate]
The photosensitive material for forming a transparent conductive film of the present invention is characterized in that the swelling ratio of the emulsion layer hardened with a hardener is more than 100% and 145% or less. Since the swelling ratio depends on the Ag: binder volume ratio, in the case of 1: 2 to 2: 1 which is the most preferable range of Ag: binder volume ratio of the present invention, it is preferably 130% or less, more preferably 120%. It is as follows. By setting the swelling ratio of the emulsion layer hardened with a hardener to the degree of swelling specified in the present invention, in particular, the adhesion to the base material after the development and intensification steps in which the emulsion layer becomes wet is achieved. In addition to being improved, it is possible to realize high scratch resistance with respect to a conveying roller or the like that contacts the emulsion layer surface side.

The swelling ratio (%) of the emulsion layer in the present invention is defined as a value obtained by measurement according to the following method.
Film thickness swell ratio (%) = {(layer film thickness when immersed in distilled water−layer film thickness before immersion) / (layer film thickness before immersion)} × 100
The film thickness of the layer when immersed in distilled water means the film thickness of the layer when the photosensitive material for forming a transparent conductive film, a silver halide photographic photosensitive material, is immersed in distilled water at 25 ° C. for 3 minutes. In the present invention, the measurement of the layer thickness is defined by the cryo SEM method. In the present invention, the adhesion between the substrate and the emulsion layer and the adhesion between the substrate and the mesh pattern can be improved by setting the swelling ratio to distilled water to 145% or less. In the present invention, as a method for controlling the swelling ratio, a method well known in the art can be used by changing the amount and type of the gelatin hardener.

<solvent>
The solvent that can be used in the preparation of the emulsion layer coating solution and the like according to the present invention is not particularly limited, and examples thereof include water, organic solvents (for example, alcohols such as methanol, ketones such as acetone, Amides such as formamide, sulfoxides such as dimethyl sulfoxide, esters such as ethyl acetate, ethers, and the like), ionic liquids, and mixed solvents thereof. Since a photographic silver halide gelatin emulsion is used, a solvent mainly containing water is preferred.

In the present invention, as described above, by reducing the film thickness, the light transmittance of the non-mesh part (light transmission part) is improved and the height of the mesh part is low and moire is reduced. The coated silver amount is 1 g / m ² or less, and the thickness of the emulsion layer of the non-mesh part (light transmission part) of the transparent conductive film obtained by forming the metallic silver part in a mesh shape is 0.1 μm or less. Preferably there is.

《Easily adhesive layer》
In the present invention, the support has an easy adhesion layer on the emulsion layer side, the refractive index of the easy adhesion layer is smaller than the refractive index of the support, and the difference in refractive index between the easy adhesion layer and the support. Is preferably within 0.1.

  This is because a polyester support having a high refractive index in the surface direction of around 1.66 (polyester is most preferable as the support) and an emulsion layer (transparent conductive material) in which the main binder is gelatin having a refractive index of about 1.52. By providing an easy adhesion layer having an intermediate refractive index between the polyester support and the easy adhesion layer adjacent to the polyester support, and the interface between the transparent conductive film and the easy adhesion layer. This is because the difference in refractive index is reduced to suppress interface reflection and to reduce interference light as a transparent conductive film.

  The easy-adhesion layer used in the present invention contains at least a resin (binder) for achieving adhesiveness and a material (refractive index adjusting agent) for obtaining a desired refractive index.

(resin)
As resin, the well-known material used as an easily bonding layer of a support body can be used, for example, acrylic resin, polyester-type resin, and urethane-type resin can be used.

  The acrylic resin can be obtained by acrylic monomers alone or by copolymerizing a plurality of types of acrylic monomers. Furthermore, it can also be produced using other monomers (comonomer).

  Examples of the acrylic monomer include acrylic acid; methacrylic acid; acrylic acid ester, such as alkyl acrylate (for example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t- Butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, phenylethyl acrylate, etc.), hydroxy-containing alkyl acrylates (eg, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, etc.); Alkyl methacrylates (eg, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate) , Isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, phenylethyl methacrylate, etc., hydroxy-containing alkyl methacrylate (for example, 2-hydroxyethyl) Methacrylates, 2-hydroxypropyl methacrylate, etc.); acrylamides; substituted acrylamides (eg, N-methylacrylamide, N-methylolacrylamide, N, N-dimethylolacrylamide, N-methoxymethylacrylamide, etc.); methacrylamide; substituted methacrylamide ( For example, N-methyl methacrylamide, N-methylol methacrylamide, , N-dimethylol methacrylamide, N-methoxymethyl methacrylamide, etc.); amino group-substituted alkyl acrylate (for example, N, N-diethylaminoethyl acrylate); amino group-substituted alkyl methacrylate (for example, N, N-diethylamino methacrylate); Epoxy group-containing acrylate (for example, glycidyl acrylate); Epoxy group-containing methacrylate (for example, glycidyl methacrylate); Acrylic acid salt (for example, sodium salt, potassium salt, ammonium salt); Methacrylic acid salt (for example, sodium salt, potassium salt) Salt, ammonium salt). The above-mentioned monomers can be used alone or in combination of two or more.

  Examples of comonomers include styrene and its derivatives; unsaturated dicarboxylic acids (eg, itaconic acid, maleic acid, fumaric acid); esters of unsaturated dicarboxylic acids (eg, methyl itaconate, dimethyl itaconate, methyl maleate, maleate) Dimethyl acid, methyl fumarate, dimethyl fumarate); unsaturated dicarboxylic acid salts (for example, sodium salts, potassium salts, ammonium salts); monomers containing sulfonic acid groups or salts thereof (for example, styrene sulfonic acid, vinyl sulfone) Acid and their salts (sodium salt, potassium salt, ammonium salt)); acid anhydrides such as maleic anhydride and itaconic anhydride; vinyl isocyanate; allyl isocyanate; vinyl methyl ether; vinyl ethyl ether; The above-mentioned monomers can be used alone or in combination of two or more.

  Examples of the polyester resin include an aqueous polyester obtained by a condensation polymerization reaction of a mixed dicarboxylic acid component and a glycol component.

  The dicarboxylic acid component is a dicarboxylic acid component having a sulfonic acid salt (dicarboxylic acid having a sulfonic acid salt and / or an ester-forming derivative thereof) in an amount of 5 to 5 with respect to all dicarboxylic acid components in the water-soluble polyester copolymer. It is a dicarboxylic acid component containing 15 mol%.

  As the dicarboxylic acid having a sulfonate and / or an ester-forming derivative thereof used in the present invention, those having an alkali metal sulfonate group are particularly preferable. For example, 4-sulfoisophthalic acid, 5-sulfoisophthalic acid, Alkali metal salts such as sulfoterephthalic acid, 4-sulfophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5- [4-sulfophenoxy] isophthalic acid or ester-forming derivatives thereof are used. Isophthalic acid sodium salt or an ester-forming derivative thereof is particularly preferred. The dicarboxylic acid and / or ester-forming derivative thereof having these sulfonates is particularly preferably used in an amount of 6 to 10 mol% based on the total dicarboxylic acid component from the viewpoint of water solubility and water resistance.

  Other dicarboxylic acid components include aromatic dicarboxylic acid components (aromatic dicarboxylic acids and / or ester-forming derivatives thereof), alicyclic dicarboxylic acid components (alicyclic dicarboxylic acids and / or ester-forming derivatives thereof), Aliphatic dicarboxylic acid components (aliphatic dicarboxylic acid and / or ester-forming derivatives thereof) and the like.

  Examples of the aromatic dicarboxylic acid component mainly include a terephthalic acid component (terephthalic acid and / or an ester-forming derivative thereof), an isophthalic acid component (isophthalic acid and / or an ester-forming derivative thereof), and the like.

  Specific examples of the aromatic dicarboxylic acid component include aromatic dicarboxylic acids such as phthalic acid, 2,5-dimethylterephthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, biphenyldicarboxylic acid, and the like. Examples include ester-forming derivatives.

  Examples of the alicyclic dicarboxylic acid and / or ester-forming derivatives thereof include 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 4 4,4'-bicyclohexyldicarboxylic acid or the like, or ester-forming derivatives thereof.

  In the present invention, a linear aliphatic dicarboxylic acid and / or an ester-forming derivative thereof may be used within a range of 15 mol% or less of the total dicarboxylic acid component. Examples of such dicarboxylic acid components include aliphatic dicarboxylic acids such as adipic acid, pimelic acid, speric acid, azelaic acid, and sebacic acid, and ester-forming derivatives thereof.

  In the present invention, ethylene glycol is preferably used in an amount of 50 mol% or more based on the total glycol component from the viewpoint of the mechanical properties of the polyester copolymer and the adhesiveness to the polyester film. As the glycol component used in the present invention, 1,4-butanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyethylene glycol and the like may be used in combination in addition to ethylene glycol.

  As the polyurethane-based resin, the following commercially available aqueous polyurethane can be used.

  Examples of commercially available waterborne polyurethanes include Takelac series W-7004, W-6010, W-605, W-512, W-511, W-405, Bayer's Impranil manufactured by Mitsui Chemicals Polyurethanes. DLH and Impranyl DLN, Dai-ichi Kogyo Seiyaku Superflex 100, Superflex 200, Superflex 300, Hydran HW-140, Hydran HW-111, Hydran HW-100, Hydran HW-101, Hydran HW-312, Hydran HW-311, Hydran HW-310, Hydran LW-513, Hydran HC-200, Hydran HC-400M, Bondick 1010C, Bondick 1050, Bondick 1070, Bondick 1310B, Bond Ikku 1310F, Bonn Dick 1310NS, Bonn Dick 1340, Bonn Dick 1510, Bonn Dick 1610NS, Bonn Dick 1630, Bonn Dick 1640, Bonn Dick 1670 (N), may be mentioned carbon Dick 1670-40 like. Among these commercially available aqueous polyurethanes, particularly preferred products are W-7004, W-605, Impranyl DLH, Impranyl DLN, Superflex 100, Superflex 200, Hydran HW-312, Hydran HW-140, Hydran HW-310, And Hydran HW-311.

(Refractive index modifier)
The refractive index adjusting agent used for the easy-adhesion layer is not particularly limited as long as the desired refractive index can be achieved, but the refractive index of the binder resin is generally around 1.5, which is relatively low. It is preferable that the agent has a relatively high refractive index such that the refractive index exceeds 1.7. Examples of such a high refractive index material include metal oxides such as tin oxide, cerium oxide, titanium oxide, yttrium oxide, lanthanum oxide, niobium oxide, and zirconium oxide. However, when the particle diameter of such a metal oxide exceeds 100 nm, the haze of the film increases. Therefore, the primary particle diameter is preferably 1 to 100 nm, and more preferably 1 to 50 nm. As the agent for achieving such a particle size, the aforementioned metal oxide sol can be preferably used. Of these, tin oxide sol and cerium oxide sol are preferable.

  The metal oxide sol can be produced by a known method. For example, for the tin oxide sol, the method described in JP-B-35-6616 can be used.

  The metal oxide sol described above is commercially available from Taki Chemical Co., Ltd., and such materials can be used.

  The easy-adhesion layer according to the present invention can be formed by coating and drying on a plastic film using a generally well-known coating method.

  Examples of coating methods that can be used include dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, or US Pat. No. 2,681,294. Examples include the extrusion coating method using the described hopper. In addition, as required, U.S. Pat. Nos. 2,761,791, 3,508,947, 2,941,898, and 3,526,528, Harasaki A method of simultaneously applying two or more layers described in Yuji's “Coating Engineering”, page 253 (published by Asakura Shoten in 1973) can also be used. Drying conditions are generally 100 to 200 ° C. and about 10 seconds to 10 minutes.

  In applying the coating liquid for the easy adhesion layer onto the support, the support can be pretreated. Pretreatment includes chemical treatment, alkali treatment, mixed acid treatment, mechanical surface-roughening treatment, corona discharge treatment, ultraviolet treatment, high-frequency treatment, glow discharge treatment, active plasma treatment, laser treatment, ozone treatment, and other surface activation treatments. Can be mentioned.

  When providing an easy-adhesion layer on the support, it can be provided before or after stretching during film formation of the support film, but it is not necessary to consider the stretchability of the easy-adhesion layer. is there.

  If necessary, a surfactant, a swelling agent, a matting agent, an antihalation dye, a pigment, an antifoggant, a preservative, and the like may be added to the coating solution.

  Moreover, you may provide a 2nd easily bonding layer on an easily bonding layer as needed. At this time, the refractive index of the second easy-adhesion layer is preferably the same as or smaller than the refractive index of the first easy-adhesion layer adjacent to the support, and is equal to or greater than the refractive index of the binder of the electromagnetic wave shielding layer. It is preferable. In particular, from the viewpoint of adhesiveness of the transparent conductive film and reduction of interference unevenness, the second easy-adhesion layer is preferably made of gelatin as a main binder.

<< Transparent conductive film and manufacturing method thereof >>
In the method for producing a transparent conductive film of the present invention, after exposing the photosensitive material for forming a transparent conductive film, development processing is performed to form a metallic silver part in a mesh shape, or after exposing the photosensitive material for forming a transparent conductive film, Development processing is performed, and further reinforcement processing is performed to form a metallic silver portion in a mesh shape.

(exposure)
In the method for producing a transparent conductive film of the present invention, pattern-like exposure is performed on an emulsion layer provided on a support. The exposure can be performed using electromagnetic waves. Examples of the electromagnetic wave include light such as visible light and ultraviolet light, and radiation such as X-rays. Furthermore, a light source having a wavelength distribution may be used for exposure, or a light source having a specific wavelength may be used.

  The method of exposing the emulsion layer in a pattern may be performed by surface exposure using a photomask or by scanning exposure using a laser beam.

(developing)
In the method for producing a transparent conductive film of the present invention, the emulsion layer is exposed and then developed (hereinafter also referred to as chemical development to distinguish it from physical development). For the chemical development, a development processing technique mainly composed of normal chemical development used for a silver salt photographic film, photographic paper, a printing plate making film, a photomask emulsion mask or the like can be used. The developer is not particularly limited as long as it is a developer mainly composed of chemical development, but a PQ developer, MQ developer, MAA developer or the like can also be used, and a lith developer such as D-85. Can be used.

  Here, “chemical development” refers to a development process in which metallic silver of an image formed by developing a latent image silver as a catalyst is formed by reducing silver ions constituting individual silver halide grains.

(Fixing)
In the present invention, fixing is performed to remove and stabilize the unexposed silver salt (silver halide grains). For fixing in the present invention, fixing techniques used for silver salt photographic film, photographic paper, film for printing plate making, emulsion mask for photomask, and the like can be used.

  In the fixing solution used in the present invention, sodium thiosulfate, potassium thiosulfate, ammonium thiosulfate, or the like can be used as a fixing agent. Aluminum sulfate, chromium sulfate, or the like can be used as a hardener for fixing. As the fixing agent preservative, sodium sulfite, potassium sulfite, ascorbic acid, erythorbic acid and the like described in the developing composition can be used, and citric acid, oxalic acid, and the like can be used.

(Reinforcement processing)
In one of the methods for producing a transparent conductive film of the present invention, the photosensitive material for forming a transparent conductive film is exposed and developed, and further, in order to improve conductivity, a reinforcing treatment is performed to form a metallic silver portion in a mesh shape. Form. Examples of the intensifying process include a physical development process and / or a plating process.

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

  In the present invention, physical development refers to reduction of metal ions such as silver ions with a reducing agent on metal or metal compound nuclei to precipitate metal particles. This physical phenomenon is used for instant B & W film, instant slide film, printing plate manufacturing, and the like, and the technology can be used in the present invention.

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

  In the present invention, the plating process can be performed using electroless plating (chemical reduction plating or displacement plating), electrolytic plating, or both electroless plating and electrolytic plating. For the electroless plating in the present invention, a known electroless plating technique can be used, for example, an electroless plating technique used in a printed wiring board or the like can be used, and the electroless plating is an electroless copper plating. Preferably there is.

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

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

(Electromagnetic wave shielding material)
The transparent conductive film of the present invention obtained by the method for manufacturing a transparent conductive film of the present invention has high conductivity and light transmittance, and is used as an electromagnetic wave shielding material with reduced interference unevenness and moire.

(Conductive metal part)
In the present invention, the electromagnetic wave shielding pattern made of the conductive metal part is formed by conducting a physical development or plating treatment on the pattern made of the metal silver part formed by the above-described exposure and development process. It is preferably formed by supporting metal particles.

  In the present invention, metallic silver is preferably formed in the exposed portion in order to increase transparency.

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

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

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

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

  Since the conductive metal portion in the present invention carries conductive metal particles, good conductivity can be obtained. For this reason, the surface resistivity of the translucent electromagnetic wave shielding film (conductive metal part) of the present invention is preferably 10Ω / □ or less, more preferably 1Ω / □ or less, and 0.5Ω / □. Most preferably:

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

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

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

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

(Functional materials other than electromagnetic shielding)
The transparent conductive film of the present invention may be separately provided with a functional layer having functionality as necessary. This functional layer can have various specifications for each application. For example, as an electromagnetic shielding material for displays, the anti-reflection layer with anti-reflection function with adjusted refractive index and film thickness, non-glare layer or anti-glare layer (both have anti-glare function), and absorbs near infrared rays. Near-infrared absorbing layers made of chemical compounds and metals, layers with a color tone adjustment function that absorbs visible light in a specific wavelength range, antifouling layers with a function that easily removes dirt such as fingerprints, and scratch-resistant hardware A coating layer, a layer having an impact absorbing function, a layer having a function of preventing glass scattering when glass is broken, and the like can be provided. These functional layers may be provided on the opposite side of the silver halide grain-containing layer and the support, or may be provided on the same side.

  These functional films may be directly bonded to the PDP, or may be bonded to a transparent substrate such as a glass plate or an acrylic resin plate separately from the plasma display panel body. These functional films are called optical filters (or simply filters), and if they are for plasma displays, they are called plasma display filters.

  In order to suppress reflection of external light and suppress a decrease in contrast, an antireflection layer provided with an antireflection function contains inorganic substances such as metal oxides, fluorides, silicides, borides, carbides, nitrides and sulfides. , Vacuum deposition method, sputtering method, ion plating method, ion beam assist method, etc., a method of laminating a single layer or a multilayer, such as a method of laminating a resin having different refractive index such as acrylic resin, fluorine resin, etc. There is. Moreover, the film which gave the antireflection process can also be affixed on this filter. Further, if necessary, a non-glare layer or an anti-glare layer can be provided. For the non-glare layer or the anti-glare layer, a method of coating fine powders such as silica, melamine, acrylic, etc. into an ink and coating the surface can be used. The ink can be cured by thermal curing or photocuring. Further, a non-glare-treated or anti-glare-treated film can be pasted on the filter. Further, if necessary, a hard coat layer can be provided.

  The near-infrared absorbing layer is a layer containing a near-infrared absorbing dye such as a metal complex compound or a silver sputtered layer. Here, the silver sputter layer can cut light of 1000 nm or more from near infrared rays, far infrared rays to electromagnetic waves by alternately laminating dielectric layers and metal layers on a substrate by sputtering or the like. The dielectric layer is a transparent metal oxide such as indium oxide or zinc oxide, and the metal layer is generally silver or a silver-palladium alloy. Usually, the dielectric layer starts with 3 layers, 5 layers, 7 or 11 layers are stacked.

  A layer having a color tone adjustment function that absorbs visible light in a specific wavelength range is displayed in blue because the PDP has a characteristic that the phosphor that emits blue light emits red light in addition to blue. There is a problem that a portion to be displayed is displayed in a purplish color, and as a countermeasure against this, it is a layer that corrects colored light and contains a dye that absorbs light at around 595 nm.

  The transparent conductive film of the present invention can be used as an electromagnetic shielding material because it has good electromagnetic shielding properties and transparency. In particular, the electromagnetic wave shielding material of the present invention is a front surface of a display such as CRT (cathode ray tube), PDP (plasma display panel), liquid crystal, EL (electroluminescence), microwave oven, electronic device, printed wiring board, etc. It can use suitably as a translucent electromagnetic wave shielding material used. Furthermore, it can be used as various conductive wiring materials such as circuit wiring.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
(Preparation of polyester support)
After drying polyethylene terephthalate pellets with an intrinsic viscosity of 0.65 dl / g at 150 ° C. for 6 hours, as a die for extrusion molding, melt extrusion at 290 ° C. using a coat hanger type T die, and applying electrostatically, about 30 ° C. The film was rapidly cooled on a cooling drum to obtain an unstretched film having a thickness of 1.1 mm. The obtained unstretched film was sequentially and longitudinally biaxially stretched under the following conditions, and was heat-set, and both ears were slit to obtain a biaxially stretched polyester support having a thickness of 100 μm.

Longitudinal stretching: Preheating roll temperature due to difference in roll peripheral speed: 78 ° C
Film temperature during stretching with infrared heater: 95 ° C
Stretch ratio: 3.3 times Lateral stretch: Stretching by stenter method Zone temperature: 100 ° C
Stretch ratio: 3.3 times Heat setting temperature: 220 ° C
(Polyester support with easy adhesion layer)
Both surfaces of the 100 μm polyester support thus obtained were subjected to a corona discharge treatment of 12 W · min / m ² , and an easy-adhesion coating solution B1 was applied to each surface to a dry film thickness of 0.1 μm. The top was subjected to a corona discharge treatment of 12 W · min / m ² , and the easy-adhesion coating solution B2 was applied to a dry film thickness of 0.06 μm. Then, heat processing was implemented at 120 degreeC for 1.5 minutes, and the polyester support body with an easily bonding layer was obtained.

<Easily adhesive coating solution B1>
Easy adhesion layer resin P-1 50g
Refractive index adjuster Z-1 (addition amounts are listed in Table 1)
Compound (UL-1) 0.2g
Finish to 1000ml with water <Easily adhesive coating solution B2>
10g gelatin
Compound (UL-1) 0.2g
Compound (UL-2) 0.2g
Silica particles (average particle size 3μm) 0.1g
Hardener (UL-3) 1g
Finish to 1000ml with water

(Easily adhesive layer resin)
P-1: Copolymer latex liquid of 20 parts by mass of styrene, 40 parts by mass of glycidyl methacrylate, and 40 parts by mass of butyl acrylate (solid content: 30%)
(Refractive index modifier)
Z-1: Tin oxide sol (synthesis of tin oxide sol)
65 g of SnCl ₄ .5H ₂ O was dissolved in 2000 ml of distilled water to obtain a homogeneous solution, which was then boiled to obtain a precipitate. The produced precipitate is taken out by decantation and washed with distilled water many times. Silver nitrate is added dropwise to distilled water in which the precipitate has been washed, and after confirming that there is no reaction of chlorine ions, distilled water is added to the washed precipitate to make a total volume of 2000 ml. To this, 40 ml of 30% aqueous ammonia was added and heated to obtain a uniform sol. Further, while adding ammonia water, the solution was concentrated by heating until the solid content concentration of SnO ₂ reached 8.3% by mass to obtain a tin oxide sol.

[Preparation of photosensitive material for forming transparent conductive film]
(Preparation of silver halide emulsion)
The following solution A was kept at 34 ° C. in a reaction vessel, and the pH was adjusted to 2.95 using nitric acid (concentration 6%) while stirring at high speed using a mixing and stirring device described in JP-A-62-2160128. It was adjusted. Subsequently, the following solution B and the following solution C were added at a constant flow rate over 8 minutes and 6 seconds using the double jet method. After completion of the addition, the pH was adjusted to 5.90 using sodium carbonate (concentration 5%), and then the following solution D and solution E were added.

(Solution A)
Alkali-treated inert gelatin (average molecular weight 100,000) 18.7g
Sodium chloride 0.31g
Solution I 1.59ml
Pure water 1246ml
(Solution B)
169.9g of silver nitrate
Nitric acid (concentration 6%) 5.89ml
Finish to 317.1 ml with pure water (Solution C)
Alkali-treated inert gelatin (average molecular weight 100,000) 5.66 g
Sodium chloride 58.8g
13.3 g of potassium bromide
Solution I 0.85ml below
Solution II below 2.72 ml
Finish to 317.1 ml with pure water.

(Solution D)
2-Methyl-4hydroxy-1,3,3a, 7-tetraazaindene 0.56 g
112.1 ml of pure water
(Solution E)
Alkali-treated inert gelatin (average molecular weight 100,000) 3.96 g
Solution I 0.40ml
128.5 ml of pure water
(Solution I)
Surfactant: 10% methanol solution of polyisopropylene polyethylene oxydisuccinate sodium salt (Solution II)
10% aqueous solution of rhodium hexachloride complex After completion of the above operation, desalting and water washing are performed using a flocculation method at 40 ° C. according to a conventional method. The pH was adjusted to 5.90 at 40 ° C., and finally a silver chlorobromide cubic grain emulsion containing 10 mol% of silver bromide and having an average grain size of 0.09 μm and a coefficient of variation of 10% was obtained.

(Solution F)
Alkali-treated inert gelatin (average molecular weight 100,000) 16.5g
Pure water 139.8ml
The silver halide emulsion was subjected to chemical sensitization at 60 ° C. for 50 minutes using 20 mg of sodium thiosulfate per mole of silver halide, and 4-hydroxy-6-methyl-1,3, after completion of chemical sensitization. 500 mg of 3a, 7-tetrazaindene (TAI) per 1 mol of silver halide and 150 mg of 1-phenyl-5-mercaptotetrazole per 1 mol of silver halide were added to obtain silver halide emulsion EM-1. In this silver halide emulsion EM-1, the volume ratio of silver halide grains to gelatin (silver halide grains / gelatin) was 0.625. Further, a coating aid (S-1) was added at 2.5 mg / m ² , a dye (F-1) was added at 30 mg / m ² , and the hardener was added as shown in Table 1 to prepare an emulsion layer coating solution. . The amount of hardener added was determined so that the emulsion layer swelling ratio shown in Table 1 was obtained.

  The coating solution thus obtained was placed on one surface of the above-mentioned easily-adhesive polyester film support so that the emulsion layer dry film thickness, non-mesh part film thickness, silver amount, presence or absence of surfactants, or the type described in Table 1 were obtained. After the coating, an aging treatment was performed at 50 ° C. for 24 hours to prepare a photosensitive material for forming a transparent conductive film.

〔exposure〕
The obtained photosensitive material was cut into A4 size and exposed with a UV exposure device through a mesh photomask (pitch / line width = 300 μm / 5 μm).

[Chemical development]
The exposed photosensitive material is developed for 60 seconds at 25 ° C. using the following developer (DEV-1), and then fixed for 120 seconds at 25 ° C. using the following fixing solution (FIX-1). It was.

(DEV-1)
500 ml of pure water
Metol 2g
80 g of anhydrous sodium sulfite
Hydroquinone 4g
4g borax
Sodium thiosulfate 10g
Potassium bromide 0.5g
Add water to bring the total volume to 1 liter (FIX-1)
750 ml of pure water
Sodium thiosulfate 250g
Anhydrous sodium sulfite 15g
Glacial acetic acid 15ml
Potash alum 15g
Add water to bring the total volume to 1 liter [Physical development]
Next, physical development was performed at 25 ° C. for 10 minutes using the following physical developer (PDEV-1), followed by washing with water and drying.

(PDEV-1)
The following A liquid and B liquid are mixed immediately before processing (A liquid).
400ml of pure water
Citric acid 10g
Disodium hydrogen phosphate 1g
Ammonia water (28% aqueous solution) 1.2ml
Hydroquinone 3g
(Liquid B)
10 ml of pure water
0.4 g of silver nitrate
(Washing treatment and drying treatment)
The washing process was performed with tap water for 10 minutes. Moreover, the drying process was dried until it became a dry state using drying air (50 degreeC).

[Electrolytic copper plating]
Furthermore, electrolytic plating was performed for 2 minutes at 6A and 25 ° C. using the following plating solution (PL-1) to prepare transparent conductive films 101 to 110 having conductive metal portions made of developed silver and copper.

(PL-1)
1000ml of pure water
200 g of copper sulfate
50g of sulfuric acid
The obtained conductive metal portion of the transparent conductive film had a mesh pattern corresponding to the exposure pattern, and in each sample, the line width was 10 μm and the pitch width was 290 μm. The aperture ratio of the light transmission portion was about 93%.

[Measurement and evaluation]
Measurement of refractive index of support and easy adhesion layer, swelling rate of emulsion layer (photosensitive material for forming transparent conductive film), plating uniformity, transmittance of transparent conductive film, surface resistance, interference unevenness and moire by the following methods evaluated.

(Swell rate)
Measurement of layer thickness before immersion After surface exposure with a microtome, the cross section of a pretreated sample coated with 1 nm of Pt-Pd is observed with SEM at an acceleration voltage of 10 kV using a S-800 made by Hitachi, and the dry film thickness is measured. did.

Measurement of layer thickness during immersion in distilled water After immersion for 3 minutes at 25 ° C. in distilled water, the film was placed in liquid nitrogen to preserve the swelling state, and then the film was cleaved with a cryo SEM system. The ice on the fractured surface was removed by raising the temperature to −70 ° C., and SEM observation was performed at an acceleration voltage of 10 kV and 5 kV using a Hitachi S-800 and a Hitachi cryo SEM system, and the swelling film thickness was measured. Using the obtained measured values, the swelling ratio was calculated by the following equation.

Film thickness swell ratio (%) = {(layer film thickness when immersed in distilled water−layer film thickness before immersion) / (layer film thickness before immersion)} × 100
(Plating uniformity)
The samples after the plating treatment were visually examined for unevenness and evaluated according to the following criteria.

○: Unevenness is hardly recognized Δ: Unevenness is slightly recognized, but is within an allowable range (about 25% of the total area)
X: Unevenness is considerably observed (about 50% of the total area)
XX: Very uneven (80% or more of the total area).

(Adhesion)
The cross cut adhesion test method of JIS-K5400 was used. A cross-shaped cut line was drawn on the sample after plating, and cellophane tape No. 1 manufactured by Nitto Denko Corporation was drawn. 29 was affixed, the tape was peeled off, and the peeled state of the film was examined. F = n ₁ / n × 100 (%) where F is the film remaining rate, n is the number of cross-cut squares, and n ₁ is the number of squares to which the film is still attached after tape peeling. evaluated.

(Transmittance)
The total transmittance in the wavelength range of 380 to 780 nm excluding the contribution of light absorption and reflection of the support of the sample having the conductive metal part and the light transmissive part obtained as described above was measured, and the conductivity The ratio with the theoretical transmittance calculated from the aperture ratio obtained by measuring the line width of the metal part was evaluated according to the following criteria.

A: Total transmittance / theoretical transmittance is 90% or more ○: Total transmittance / theoretical transmittance is 80% to less than 90% Δ: Total transmittance / theoretical transmittance is 70% to less than 80% ×: Total transmittance / Theoretical transmittance is less than 70%.

(Surface resistance)
The surface resistance of the conductive metal portion of the transparent conductive film was measured using a resistivity meter Loresta GP series 4-probe probe manufactured by Dia Instruments Co., Ltd., and 20 points were measured to obtain an average.

(Interference unevenness)
The sample was placed on a black board with the emulsion layer facing upward, illuminated with a 27 W three-wavelength fluorescent lamp from above, and visually checked for the presence or absence of interference unevenness, and evaluated according to the following criteria.

○: Unevenness is not recognized Δ: Unevenness is slightly recognized ×: Unevenness is considerably recognized

(Moire)
A sample was placed on the front face of a Hitachi PDP TV and a Matsushita Electric PDP TV at a bias angle with a minimum moire, and visual sensory evaluation was performed. While observing the television screen directly, the image display surface was observed by changing the observation position with respect to the television screen at various positions such as oblique, and evaluated according to the following criteria.

○: Moire is not recognized Δ: Moire is slightly recognized ×: Moire is considerably recognized Table 1 shows the results of measurement and evaluation.

As is clear from Table 1, the adhesiveness of the photosensitive material for forming a transparent conductive film in which the swelling ratio of the emulsion layer of the present invention is 145% or less is good, and the adhesiveness between the mesh line and the substrate is sufficient It can be seen that the plating uniformity is also good. When the adhesion is insufficient, film peeling occurs during the plating process, so that the desired surface resistance value cannot be processed, resulting in a high resistance value. Further, the silver halide coating silver amount is 1 g / m ² or less, and the thickness of the emulsion layer in the non-mesh part (light transmission part) of the transparent conductive film obtained by forming the metallic silver part in a mesh shape is 0.00. It can be seen that the transparent conductive film of the present invention produced at 1 μm or less satisfies high transmittance and high conductivity at the same time, and moire is reduced. It can also be seen that interference unevenness is reduced when the refractive index of the easy adhesion layer is smaller than the refractive index of the support and the difference in refractive index between the easy adhesion layer and the support is within 0.1.

Example 2
Samples 201 to 204 were prepared in the same manner as Sample 105 except that gelatin E in Sample 105 of Example 1 was replaced with gelatin A to D shown in Table 2, and evaluated in the same manner as in Example 1. The results are shown in Table 2.

  The content of divalent or higher polyvalent metal ions in gelatin described in Table 2 was determined by adjusting the degree of ion exchange treatment in the gelatin production process.

  As is apparent from Table 2, the photosensitive material for forming a transparent conductive film in which the content of divalent or higher polyvalent metal ions in the gelatin of the present invention is 500 ppm or less has no plating unevenness and exhibits a higher effect.

Claims (8)

A transparent conductive film having an emulsion layer comprising at least silver halide and a binder on a support and capable of producing a transparent conductive film by forming a metallic silver portion in a mesh shape by developing after exposure. A photosensitive material for formation, wherein the swelling ratio of the emulsion layer is hardened with a hardener to be greater than 100% and less than or equal to 145% , and the binder is a hydrophilic polymer mainly composed of gelatin, A photosensitive material for forming a transparent conductive film, wherein the amount of polyvalent metal ions in gelatin is more than 0 ppm and 500 ppm or less . The silver halide coating silver amount is 0.1 to 1 g / m ² and the thickness of the emulsion layer of the non-mesh portion (light transmissive portion) of the transparent conductive film in which the metallic silver portion is formed in the mesh shape is The photosensitive material for forming a transparent conductive film according to claim 1, wherein the photosensitive material is 0.05 to 0.2 μm. A transparent conductive film for forming the light-sensitive material according to claim 1 or 2, characterized in that said emulsion layer is hardened with a hardener total binder 1g per 150~500mg present on the same side. 4. The photosensitive material for forming a transparent conductive film according to claim 3 , wherein the hardener contained in the emulsion layer is at least one triazine derivative. The support is a support in which at least one easy-adhesion layer is coated adjacently, the refractive index of the support is greater than that of the easy-adhesion layer, and the difference in refractive index between the support and the easy-adhesion layer The photosensitive material for forming a transparent conductive film according to any one of claims 1 to 4 , wherein the photosensitive material is within 0.1. A metal silver part is formed in a mesh shape by exposing the photosensitive material for forming a transparent conductive film according to any one of claims 1 to 5 to a developing process after the exposure, and further performing a reinforcing process. A method for producing a transparent conductive film. A transparent conductive film obtained by the production method according to claim 6 . An electromagnetic wave shielding material using the transparent conductive film according to claim 7 .