JP2008288305A - Electromagnetic wave shield film and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic wave shield film having superior electromagnetic wave cut-off capability and high transparency and having less spot defectives on a mesh pattern to offer superior mesh uniformity and a method for manufacturing the electromagnetic wave film, and to provide an electromagnetic wave shield film which hardly allows a plating layer on the mesh pattern to peel even in production of a long continuous roll, shows less time-dependent color change, and is highly stable, and a method for manufacturing the electromagnetic wave shield film. <P>SOLUTION: In the method for manufacturing the electromagnetic wave shield film, a silver halogenide photosensitive material having a transparent support is exposed to light and is subjected to a development process to form a metal silver mesh portion, which is then subjected to a copper plating process to form a highly conductive mesh portion. A copper sulfate used for the copper plating process is a refined copper sulfate having an iron (Fe) content rate of 100 ppm or lower. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to 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 a method for manufacturing the same.

  In recent years, the use of electronic devices such as display devices used in mobile phones, personal computers, TVs and the like has increased, but electromagnetic waves are generally emitted from these electronic devices, It is known that so-called electromagnetic interference (EMI) occurs, such as malfunction of electronic and electrical equipment, failure, or the possibility of harming the human body. Along with this, there is an increasing need to reduce such EMI, and standards or regulations regarding the intensity of electromagnetic wave emission are established mainly in Europe and the United States, and recent electronic devices are required to meet these standards. Yes. In particular, it is necessary to achieve both electromagnetic shielding performance and transparency for equipment that requires visibility such as CRT, flat panel display, and window glass. These are generally provided with a conductive metal pattern on a transparent resin film, and a continuous metal mesh pattern is formed on a long transparent resin film to improve its light transmission and conductivity. Further, the metal mesh is reinforced by plating (for example, see Patent Documents 1 to 4).

However, plating of a fine metal mesh with a line width of about 10 μm and a line interval of about 200 μm requires a high degree of control because even a small spot has a large influence. In particular, in the case of a method in which a silver halide light-sensitive material is exposed and developed, and a mesh pattern is formed by intensifying treatment such as physical development or plating, it is cheaper and more productive than conventional sputtering or printing methods. Although high, there is a problem that spot defects and uneven plating easily occur in the plating process. Furthermore, peeling of the plating layer and discoloration of the mesh over time are also problems.
WO 01/51276 pamphlet International Publication No. 04/7810 Pamphlet JP 2004-221564 A International Publication No. 06/88059 Pamphlet

  The present invention has been made in view of the above problems, and its purpose is an electromagnetic wave shielding film having excellent electromagnetic wave shielding performance, high transparency, few mesh pattern spot defects, and excellent mesh uniformity. It is another object of the present invention to provide an electromagnetic wave shielding film excellent in stability and a method for producing the same, in which the plating layer of the mesh pattern is hardly peeled off even in the production of the long continuous roll, and the discoloration with time is little.

  As a result of studying the above problems, the present inventors have found that an excellent transparent electromagnetic wave shielding film can be obtained by improving the frame portion of the metal mesh pattern.

  That is, the object of the present invention is achieved by the following.

  1. An electromagnetic wave in which a silver halide photosensitive material having a transparent support is exposed to light and developed to form a metal silver mesh portion, and the metal silver mesh portion is further subjected to copper plating to form a highly conductive mesh portion. In the manufacturing method of a shield film, the copper sulfate used for this copper plating process is a refined copper sulfate whose iron (Fe) content rate is 100 ppm or less, 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 an iron (Fe) content of the copper sulfate is 50 ppm or less with respect to copper (Cu).

  3. 3. The method for producing an electromagnetic shielding film according to 1 or 2, wherein the copper sulfate has a silicon (Si) content of 20 ppm or less with respect to copper (Cu).

  4). 4. The method for producing an electromagnetic wave shielding film according to any one of 1 to 3, wherein a content of at least one of Ca and Mg of the copper sulfate is 5 ppm or less with respect to copper (Cu).

  5. 5. The method for producing an electromagnetic wave shielding film according to any one of 1 to 4, wherein the copper sulfate is high-purity copper sulfate having a purity of 99.99% or more.

  6). The electromagnetic wave shielding film according to any one of 1 to 5, wherein a copper plating solution used for the copper plating treatment contains 0.1 to 100 ppm of silver (Ag) with respect to copper (Cu). Manufacturing method.

  7. The method for producing an electromagnetic wave shielding film according to any one of 1 to 6, wherein the copper plating obtained by the copper plating treatment is electrolytic copper plating.

  8). 8. The method for producing an electromagnetic wave shielding film according to any one of 1 to 7, wherein the development treatment comprises chemical development treatment, fixing treatment, and physical development treatment.

  9. 9. The method for producing an electromagnetic wave shielding film according to any one of 1 to 8, wherein the electromagnetic wave shielding film is continuously produced by a long roll having a width of 50 cm or more.

  10. 10. The method for producing an electromagnetic wave shielding film as described in any one of 1 to 9 above, wherein the silver halide of the silver halide photosensitive material contains 70 mol% or more of silver chloride.

  11. An electromagnetic wave shielding film having a highly conductive mesh part formed by copper plating on the surface of a silver mesh on a transparent support, wherein Ag is present on the surface of the highly conductive mesh part Shield film.

  According to the present invention, an electromagnetic wave shielding film excellent in electromagnetic wave shielding performance, having high transparency, having few mesh pattern spot defects, and excellent in mesh uniformity, and a method for producing the same, and further in production of long continuous rolls However, it is possible to provide an electromagnetic wave shielding film that is less likely to peel off the plating layer of the mesh pattern, has little discoloration over time, and has excellent stability, and a method for manufacturing the same.

  In the present invention, a silver halide photosensitive material having a transparent support is exposed to light and developed to form a metal silver mesh portion, and the metal silver mesh portion is further plated to form a highly conductive mesh portion. The present invention relates to a formed electromagnetic wave shielding film and a manufacturing method thereof. In particular, the present invention relates to an electromagnetic wave shielding film characterized in that metallic silver is present on the surface of the metal plating coating and a method for producing the same. The present invention also relates to a production method suitable for continuously producing an electromagnetic shielding film with a long roll.

  Hereinafter, the best mode for carrying out the present invention will be described in detail, but the present invention is not limited thereto.

(Transparent support)
In the present invention, a normal synthetic resin film can be used as the transparent support (hereinafter also referred to as a support).

  For example, cellulose ester film, polyester film, polycarbonate film, polyarylate film, polysulfone (including polyethersulfone) film, polyethylene terephthalate, polyethylene naphthalate polyester film, 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, polymethylpentene film, polyether ketone film, Polyetherketoneimide film, polyamid Film, fluororesin film, a nylon film, a polymethyl methacrylate film or an acrylic film or the like. In addition to these plastic films, quartz glass, soda glass, and the like can be used.

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

  In the present invention, it is particularly preferable to use a polyethylene terephthalate film or a polyethylene naphthalate film that is a polyester film as the support from the viewpoints of transparency, isotropic properties, adhesiveness, durability, and the like.

  When the electromagnetic wave shielding film of the present invention is used for a display screen of a display, high transparency is required. Therefore, it is desirable that the support itself has high transparency. In this case, the average transmittance in the visible light region of the plastic film or glass plate is preferably 85 to 100%, more preferably 90 to 100%. Moreover, in this invention, what colored the said plastic film or glass plate to the extent which does not interfere with the objective of this invention can also be used as a color tone regulator. 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 measurement, the measurement aperture needs to be sufficiently larger than the mesh pattern described above, and is obtained by measuring at least an area 100 times larger than the mesh area of the mesh.

  The support used in the present invention is 100 m or more, more preferably 500 m or more, still more preferably 1000 m or more and 2000 m or less in order to produce the continuous support as a long roll.

  The width of the support used in the present invention is 1 m or more, preferably 1.5 m or more, and more preferably 2 m or more and 5 m or less because of the demand for a display panel with a larger screen.

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

(Mesh part)
The line width of the conductive metal mesh portion formed for shielding electromagnetic waves is usually 20 μm or less, preferably 18 μm or less, more preferably 15 μm or less, even more preferably 3 μm or more, from the viewpoint of making the mesh inconspicuous. 10 μm or less is most preferable. If it is less than 3 μm, the conductivity is slightly insufficient.

  The line spacing of the mesh part is preferably 150 μm or more, more preferably 180 μm or more, and particularly preferably 200 μm or more. The thickness of the fine mesh wire is preferably 0.1 μm or more and 25 μm or less, more preferably 0.2 or more and 20 μm or less, and particularly preferably 0.5 μm or more and 15 μm or less.

  The mesh portion in the present invention preferably has an aperture ratio of more than 80%, more preferably 85% or more, and most preferably 90% or more from the viewpoint of visible light transmittance. The aperture ratio is the ratio of the portion without fine lines forming the mesh to the whole. For example, the aperture ratio of a square lattice mesh having a line width of 10 μm and a pitch of 200 μm is 90%.

  In the present invention, in order to give high translucency and high electromagnetic wave shielding performance, a lattice-like fine line mesh pattern is drawn by exposure, and then a development process or the like is performed to form a conductive mesh pattern. An electromagnetic wave shielding film is preferred.

(Frame part)
The frame portion is a connection portion for grounding a current generated by absorbing electromagnetic waves in the mesh portion, and generally forms a strip-shaped frame in order to improve conductivity.

(Mesh formation method)
In the electromagnetic wave shielding film of the present invention, the method for forming a conductive mesh having an electromagnetic wave shielding function is a known method, that is, a vapor deposition method, various printing methods (gravure printing, screen printing, offset printing, ink jet printing), etching method, A photolithographic method or the like can be used, but a silver salt photographic method in which a silver halide photosensitive material is formed by exposure, development processing, and intensification processing as necessary is preferable.

(Silver halide)
When the electromagnetic wave shielding film of the present invention is formed using a silver salt photography method, a silver halide emulsion-containing layer containing a silver halide and a binder described later is provided on the support. In addition to this, a hardening agent, a thickening agent, an activator, etc. can be contained.

In the present invention, the content of the silver halide in terms of silver in 0.05 g / m ² or more, preferably less than 3 g / m ^2, particularly preferably in terms of silver 0.3 g / m ² or more and less than 1 g / m ² It is. When the silver halide content is less than 0.05 g / m ² , it is difficult to obtain sufficient electromagnetic wave shielding performance. This is presumed to be because the amount of developed silver nuclei serving as a catalyst for physical development or metal plating treatment described later becomes insufficient and it becomes difficult to form an effective conductive mesh. In addition, when the silver halide content is 3 g / m ² or more, the amount of silver halide relative to the binder is relatively large, so that the film tends to become brittle and it is difficult to maintain sufficient film strength. It becomes.

  When the amount of the binder is increased in order to maintain the physical properties of the film, the distance between the grains of the silver halide grains is increased, so that it becomes difficult to form a developed silver network, and it becomes difficult to form an effective conductive mesh. The durability against changes in humidity is insufficient, and the effects of the present invention are difficult to obtain.

In the present invention, the binder amount of the silver halide light-sensitive material is particularly preferably 10 mg / m ² or more and 0.2 g / m ² or less from the viewpoint of achieving both conductivity and film properties. When the amount of the binder is less than 10 mg / m ^2, the amount of silver halide relative to the binder is relatively large, so that the coating tends to become brittle and it is difficult to maintain sufficient coating strength. On the other hand, when the amount of the binder is more than 0.1 g / m ² , the distance between the grains of the silver halide grains becomes large, so that it becomes difficult to form a developed silver network, and it becomes difficult to form an effective conductive mesh. Further, durability against changes in temperature and humidity becomes insufficient, and the effects of the present invention cannot be obtained.

  The composition of the silver halide grains used in the present invention has an arbitrary halogen composition such as silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide and silver chloroiodide. However, in order to obtain metallic silver having good conductivity, fine particles having high sensitivity are preferable, and silver chloride-containing particles are preferably used. Particularly preferred are those containing 70 mol% or more of silver chloride.

  In order to reduce the surface specific resistance after silver halide grains are developed to become metallic silver grains and effectively shield electromagnetic waves, the contact area between developed silver grains needs to be as large as possible. For this purpose, a smaller silver halide grain size is better to increase the surface area ratio, but too small grains tend to agglomerate into large agglomerates, in which case the contact area will be reduced, so there is an optimum grain size. To do. In the present invention, the average grain size of the silver halide grains is preferably 0.01 to 0.5 μm, more preferably 0.03 to 0.3 μm, in terms of a sphere equivalent diameter. In addition, the sphere equivalent diameter of silver halide grains represents the diameter of grains having the same volume and having a spherical shape. The average grain size of silver halide grains is the temperature at the time of preparation of silver halide grains, pAg, pH, addition rate of silver ion solution and halogen solution, grain size control agent (for example, 1-phenyl-5-mercaptotetrazole, 2-mercaptobenzimidazole, benztriazole, tetrazaindene compounds, nucleic acid derivatives, thioether compounds, etc.) can be appropriately combined and controlled.

In the present invention, an embodiment in which the value obtained by dividing the coating silver amount (g / m ² ) by the particle size (μm) is 6 or more and 25 or less is preferable. When a large amount of silver halide having a relatively small grain size is used, this value tends to be larger than 25. In this case, the silver halide grains are likely to slip off from the coating at the edge portion when the film is cut. There is a tendency. In addition, when a small amount of silver halide having a relatively large grain size is used, this value tends to be smaller than 6, and in this case, the number of silver halide grains in a unit area tends to decrease, so that the conductivity tends to decrease. It is because it becomes.

  In the present invention, the shape of the silver halide grains is not particularly limited, and for example, spherical, cubic, flat plate (hexagonal flat plate, triangular flat plate, tetragonal flat plate, etc.), octahedron, tetrahedron It can be in various shapes such as shapes. In order to increase the sensitivity, tabular grains having an aspect ratio of 2 or more, 4 or more, and further 8 to 16 can be preferably used. The particle size distribution is not particularly limited, but a narrow distribution is preferable from the viewpoint of enhancing the transparency while sharply reproducing the outline of the pattern and maintaining high conductivity during pattern formation by exposure. The particle size distribution of the silver halide grains used in the silver halide photosensitive material according to the present invention is preferably monodispersed silver halide grains having a coefficient of variation of 0.22 or less, more preferably 0.15 or less. Here, the variation coefficient is a coefficient representing the breadth of the particle size distribution, and is defined by the following equation.

Coefficient of variation = S / R
(In the formula, S represents the standard deviation of the particle size distribution, and R represents the average particle size.)
The silver halide grains 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, Group 8-10 metal ions such as iron ion, rhodium ion, ruthenium ion and iridium ion are preferably used because the difference between the exposed portion and the unexposed portion tends to be clearly generated when the metal silver image is generated.

  These metal ions can be added to the silver halide emulsion in the form of a salt or a complex salt. 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 metal ion compound contained in the silver halide is preferably 10 ⁻¹⁰ to 10 ⁻² mol / mol Ag per mol of silver halide, and is preferably 10 ⁻⁹ to 10 ^−. More preferably, it is ³ mol / mol Ag.

  In order for silver halide grains to contain the above-described metal ions, the metal compound is subjected to physical ripening before formation of silver halide grains, during formation of silver halide grains, after formation of silver halide grains, etc. What is necessary is just to add in the arbitrary places in a process. Moreover, in addition, the solution of a heavy metal compound can be continuously performed over the whole or a part of particle formation process.

  In the present invention, in order to further improve the sensitivity, chemical sensitization performed with a photographic emulsion or spectral sensitization can be performed.

(binder)
In the silver halide photosensitive layer according to the present invention, the silver halide grains are uniformly dispersed, and the silver halide grains are supported on a support, and the silver halide photosensitive layer and other layers, or the support, A binder is used for the purpose of ensuring the adhesion of the resin. The binder that can be used in the present invention is not particularly limited, and any of a water-insoluble polymer and a water-soluble polymer can be used. From the viewpoint of improving developability, it is preferable to use a water-soluble polymer.

  In the light-sensitive material according to 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, simple substances. Hydrophilic colloids such as synthetic hydrophilic polymer materials such as mono- or copolymers can also be used.

  When gelatin is used as the binder, it is preferable to use gelatin from which ionic impurities have been removed by ion exchange treatment or the like. Also preferred are those in which, for example, a sulfur compound is reduced, which affects the performance of silver halide. Furthermore, it is preferable that the molecular weight distribution of gelatin is controlled in a uniform direction by an enzymatic decomposition method or the like in the gelatin formation process.

  In the present invention, the silver / binder mass ratio of the silver halide photosensitive layer is preferably from 0.5 to 20. This is to increase the contact area between the developed silver particles described above, more preferably 1.0 or more and 10 or less, still more preferably 3.0 or more and 8.0 or less.

(Layer structure of silver halide photosensitive material)
The layer structure of the silver halide photosensitive material for forming an electromagnetic wave shielding film of the present invention basically comprises a support and a silver halide photosensitive layer. Furthermore, it is preferable to provide various layers in consideration of not only high functionality, processing characteristics and durability as an electromagnetic wave shielding film but also the production efficiency and production stability of the silver halide photosensitive material.

  For example, a non-photosensitive intermediate layer is provided between the support and the silver halide photosensitive layer, or a backing layer is provided on the opposite side of the support from the silver halide photosensitive layer. It is preferable to provide a protective layer on the conductive layer. These layers may be composed of a plurality of layers.

  In the present invention, it is also preferable to provide a silver halide photosensitive layer on both sides of the support and to form a conductive pattern on each. In this case, it is preferable that the silver halide emulsion coated on each surface has sensitivity at different wavelengths by spectral sensitization or the like. By giving sensitivity to different wavelengths on the front and back surfaces, it is possible to produce different conductive patterns on each surface, for example, to selectively shield against electromagnetic waves of different frequencies on the front and back surfaces. It is also possible to form a conductive pattern.

(Method for producing electromagnetic shielding film)
The basic method for producing the electromagnetic wave shielding film of the present invention is as follows: (1) a step of coating a silver halide emulsion on a support, (2) a step of drying the coated silver halide photosensitive material, (3) A step of pattern exposure of the formed silver halide photosensitive material, (4) a step of developing the exposed silver halide photosensitive material to form a metallic silver portion and a light transmitting portion, and (5) the metallic silver. And a step of plating the portion to form a highly conductive metal portion.

  Each of these steps may be batch-processed independently, but it is preferable that each step is linked to a continuous web from the feeding of the support. Finally, the formed electromagnetic wave shielding film may be obtained as a long roll, or the formed electromagnetic wave shielding film may be cut and integrated in a sheet form.

(Coating process)
A coating process is a process of apply | coating the said structural layer on a support body. Examples of the coating method include a dip coating method, a spray coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, an inkjet coating method, or US Pat. No. 2,681,294. Examples include an extrusion coating method using a hopper described in the specification. If necessary, U.S. Pat. Nos. 2,761,791, 3,508,947, 2,941,898 and 3,526,528, Yuji Harasaki, “ The method of simultaneously applying two or more layers described in “Coating Engineering” on page 253 (published by Asakura Shoten in 1973) can also be preferably used.

(Exposure process)
In the present invention, the silver halide photosensitive material is exposed in order to form a conductive pattern by performing at least one selected from development processing, physical development and plating processing described later. Examples of the light source used for exposure include ultraviolet light, visible light, infrared light, etc., electron beam, X-ray radiation, etc., and visible light is used in terms of utilizing the characteristics of silver halide. preferable. In particular, it is preferable to use a light source having a narrow wavelength distribution because the formation of the electromagnetic shielding film can be efficiently controlled and can be stably produced.

  In the present invention, it is particularly preferable to perform exposure using a laser beam. Among various laser beams, a blue laser is preferable because of the photosensitive characteristics of silver halide. The emission wavelength is preferably 370 to 450 nm, particularly 415 to 440 nm.

Specifically, a helium-cadmium laser (about 442 nm), a blue semiconductor laser using an InGaN-based material with an oscillation wavelength of 400 to 430 nm, a GaAlAs-based (laser wavelength 850 nm) semiconductor laser, an MgO: LiNbO ₃ SHG crystal. However, a blue semiconductor laser is preferable from the viewpoints of compactness, low power consumption, stability, long life, and the like. In particular, a blue semiconductor laser announced by Nichia Chemical Co., Ltd. at the 48th Applied Physics Related Conference in March 2001 is preferred.

(Development processing)
In the present invention, after the silver halide photosensitive material is exposed, development processing is performed. The development process is preferably a so-called black-and-white development process that does not contain a color developing agent.

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

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

  The development processing solution used in the development processing can contain an image quality improver for the purpose of improving the image quality. Examples of the image quality improver include nitrogen-containing heterocyclic compounds such as 1-phenyl-5-mercaptotetrazole and 5-methylbenzotriazole.

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

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

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

  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.

(Reinforcement processing, physical development processing)
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 photosensitive 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 can be performed by immersing a silver halide photosensitive 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.

  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, the most preferable development processing step includes chemical development processing (black and white development processing), fixing processing, and physical development processing in this order.

(Plating treatment)
In the present invention, various conventionally known plating methods can be used for the plating treatment. For example, electrolytic plating and electroless plating can be carried out 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. In the case of electroless plating, there is an 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 treatment is relatively easy and high conductivity is easily obtained.

  The above processing can be performed during development, at any timing after development, before fixing, and after fixing processing. However, from the viewpoint of maintaining high transparency of the film, it is preferably performed after the fixing processing.

  In the present invention, the amount of metal applied by physical development or metal plating is 10 times or more and 100 times or less in terms of mass relative to developed silver obtained by exposing and developing a silver halide photosensitive material. Some embodiments are preferred. This value can be determined by quantifying the metal contained in the silver halide photosensitive material by, for example, fluorescent X-ray analysis before and after physical development or metal plating. When the amount of metal applied by physical development or metal plating is less than 10 times in terms of mass relative to developed silver obtained by exposing and developing a silver halide photosensitive material, the conductivity is slightly reduced. If the ratio is larger than 100 times, the transmittance tends to decrease due to metal deposition on unnecessary portions other than the conductive mesh pattern portion. In the present invention, it is preferable to perform both physical development and metal plating.

  In the present invention, a silver halide photosensitive material having a support is exposed and developed to form a metallic silver mesh portion, and the metallic silver mesh portion is further subjected to copper plating to form a highly conductive mesh portion. In the manufacturing method of the electromagnetic wave shielding film to be formed, the copper sulfate used for the copper plating is found to exhibit the effects of the present invention by a manufacturing method using purified copper sulfate having an iron (Fe) content of 100 ppm or less. It is a thing.

  Many commercially available copper sulfates for copper plating contain metal salts other than copper as impurities, which can be said to be a problem-free level for general copper plating applications such as electrical parts. In the case of an electromagnetic wave shielding film having a fine electromagnetic wave shielding mesh and copper plating on a metallic silver mesh formed by exposure and development processing of a silver halide photosensitive material, such impurities are large in quality. I found out that it affected.

  In particular, the Fe content in copper sulfate is preferably 50 ppm or less and particularly preferably 5 ppm or less with respect to Cu. Moreover, it is preferable that it is 20 ppm or less with respect to Cu, and, as for the silicon (Si) content rate in copper sulfate, it is especially preferable that it is 5 ppm or less. It has been found that spot defects generated in the plating process can be reduced by reducing these impurities.

  The content of at least one of Ca and Mg in the copper sulfate is preferably 5 ppm or less and particularly preferably 1 ppm or less with respect to Cu. It has been found that by reducing these impurities, plating unevenness generated in the plating process can be reduced.

  Under such circumstances, as the copper sulfate used in the present invention, it is preferable to use high-purity copper sulfate having a purity of 99.9% or more, preferably 99.99% or more, and other metal salts are several ppm or less. Is particularly preferred.

  Furthermore, in this invention, when the copper plating solution using the said copper sulfate contains 0.1-100 ppm of silver (Ag) with respect to Cu, the plating layer which generate | occur | produces at a metal-plating process and peeling of a mesh are carried out. It has been found that discoloration can be reduced.

  In the present invention, the copper plating solution can be applied to electroless copper plating, but has been found to be particularly effective in electrolytic copper plating.

  In the present invention, when the electromagnetic wave shielding film is continuously produced in the form of a long roll having a width of 50 cm or more, that is, by controlling impurities and silver content in continuous electrolytic copper plating related to continuous production, the effect is particularly effective. Demonstrate.

  In the present invention, in the electromagnetic wave shielding film in which the metal silver mesh portion is subjected to metal plating treatment other than silver to form a highly conductive mesh portion, the presence of metal silver on the surface of the metal plating coating allows the present invention to It was found to have the effect of. Further, the metallic silver present on the surface of the metal plating coating is highly effective when it is in the form of fine particles.

  The presence of metallic silver on the surface of the copper plating coating can be detected by conducting a metal analysis on a fine portion of the mesh surface by fluorescent X-ray analysis using an electron microscope.

  The presence of metallic silver on the surface of the metal plating coating can be achieved by adding a small amount of silver ions to the plating solution. The effect of the present invention was remarkable when the silver ion concentration in the plating solution was in the range of 0.1 to 100 ppm relative to the plating metal ions.

  For example, in the case of copper electrolytic plating, when a developed silver that has been subjected to development treatment is copper-plated using a copper plating solution to which a small amount of silver has been added, the developed silver serving as a base is covered with a cross-sectional view of the mesh line. The copper plating part currently formed in this, and the layer considered to be a silver-copper mixed crystal part in the middle were able to be detected. When this mixed crystal portion was present, it was found that the adhesion between developed silver and copper plating is strong and difficult to peel off, and the conductivity tends to be high.

(Oxidation treatment)
In the present invention, it is preferable to carry out an oxidation treatment after the development treatment, physical development or plating 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.

  As the treatment liquid used for the oxidation treatment, for example, a treatment method using an aqueous solution containing Fe (III) ions, or hydrogen peroxide, persulfate, perborate, perphosphate, percarbonate, perhalogenate. A treatment solution containing a conventionally known oxidant such as a method of treating with an aqueous solution containing a peroxide such as a hypohalite, a halogenate, or an organic peroxide can be used. The oxidation process is preferably performed after the development process and before the plating process because the transmittance can be improved efficiently in a short time, and particularly preferably after the physical development. This is the mode to be performed.

(Blackening treatment)
In the present invention, it is preferable to perform a blackening treatment on the surface of the metal mesh from the viewpoint of preventing external light reflection on the surface of the electromagnetic wave shielding film. When such a blackened transparent electromagnetic wave shielding film is used for a display such as a PDP, for example, it is possible to reduce a decrease in contrast due to reflection of external light, and to maintain a high-quality black tone when not in use. Can be preferable. The blackening treatment method is not particularly limited, and known methods can be used alone or in combination as appropriate. For example, when the outermost surface of the conductive pattern is made of metallic copper, a method of oxidizing by immersing in an aqueous solution containing sodium chlorite, sodium hydroxide, or trisodium phosphate, or copper pyrophosphate or pyrophosphoric acid A method of blackening by dipping in an aqueous solution containing potassium and ammonia and performing electrolytic plating can be preferably used. If the outermost layer of the conductive pattern is made of a nickel-phosphorus alloy coating, immerse it in an acidic blackening solution containing copper (II) chloride or copper (II) sulfate, nickel chloride or nickel sulfate, and hydrochloric acid. The method to do can be used preferably.

  In addition to the above-described method, the blackening treatment can be performed by a method of finely roughening the surface. However, from the viewpoint of maintaining high conductivity, oxidation is more effective than finer roughening of the surface. A blackening treatment method is preferred.

(Near-infrared absorbing layer)
When the electromagnetic wave shielding film of the present invention is used in combination with, for example, an optical filter for a plasma display panel (PDP), near infrared absorption, which is a layer containing a near infrared absorbing dye under the silver halide photosensitive layer. It is also preferred to provide a layer. In some cases, the near-infrared absorbing layer may be provided on the opposite side of the support to the silver halide grain layer side, or may be provided on both the silver halide grain layer side and the opposite side. A near-infrared absorbing layer can be provided between the silver halide grain layer containing silver halide and the support, or a near-infrared absorbing layer can be provided on the opposite side of the support as viewed from the silver halide grain layer. The former is preferred because it can be applied simultaneously with one side of the support.

  Specific examples of near-infrared absorbing dyes include polymethine, phthalocyanine, naphthalocyanine, metal complex, aminium, imonium, diimonium, anthraquinone, dithiol metal complex, naphthoquinone, indolephenol, azo System, tri, and allylmethane 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.

  As a near-infrared absorbing dye, diimonium compounds are IRG-022, IRG-040 (above, 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 (above, trade names manufactured by Mitsui Chemicals, Inc.) and phthalocyanine compounds are commercially available products such as IR-10, IR-12 (above, trade names of Nippon Shokubai Co., Ltd.). can do.

  When the electromagnetic shielding film of the present invention is used in combination with, for example, an optical filter for a plasma display panel (PDP), for example, 595 nm is used as a countermeasure to prevent a decrease in color reproducibility due to emission lines of neon gas emission lines used in PDP. The aspect containing the pigment | dye which absorbs near light is preferable. Specific examples of the dye that absorbs such a specific wavelength include, for example, azo, condensed azo, phthalocyanine, anthraquinone, indigo, perinone, perylene, dioxazine, quinacridone, methine, Well-known organic pigments and organic dyes such as isoindolinone-based, quinophthalone-based, pyrrole-based, thioindigo-based, and metal complex-based materials, and inorganic pigments may be mentioned. Among these, phthalocyanine-based and anthraquinone-based dyes are particularly preferably used because of good weather resistance.

(UV absorbing layer)
In the present invention, it is preferable to use an ultraviolet absorber having a maximum absorption wavelength of less than 350 nm in order to avoid deterioration of the electromagnetic wave shielding film due to ultraviolet rays.

  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. There are no particular restrictions on the layer added to these ultraviolet absorbers, but from the viewpoint of preventing the binder used in the silver halide photosensitive layer (mesh pattern layer) from being deteriorated by ultraviolet rays, it is added to the silver halide photosensitive layer. Or the aspect provided in the light source side rather than this layer is preferable.

  Preferred ultraviolet absorbers include benzotriazoles, for example, compounds represented by general formula [III-3] described in JP-A-1-250944, and general formula [III] described in JP-A 64-66646. A compound represented by general formula [I] described in JP-A No. 63-187240, UV-1L to UV-27L described in JP-A No. 63-187240, JP-A No. 4-1633, and JP-A No. 5-165144 The compounds represented by the general formulas (I) and (II) are preferably used.

  These ultraviolet absorbers are used in, for example, high-boiling organic solvents represented by phthalates such as dioctyl phthalate, di-i-decyl phthalate, and dibutyl phthalate, and phosphate esters such as tricresyl phosphate and trioctyl phosphate. It is preferable to add in a dispersed manner. Moreover, the aspect which adds these ultraviolet absorbers directly to a support body is also used preferably, In this case, the aspect as described, for example in Japanese translations of PCT publication No. 2004-531611 can also be used preferably.

(Antireflection layer)
When the electromagnetic wave shielding film of the present invention is used for the purpose of protecting a display screen or the like, it is preferable to provide an antireflection layer.

  The layer having an antireflection function is preferably composed of a plurality of light-transmitting layers having different refractive indexes, and is preferably composed of a high refractive index layer, a medium refractive index layer, and a low refractive index layer containing inorganic fine particles. preferable. 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.

  As the antireflection layer, inorganic materials such as metal oxides, fluorides, silicides, borides, carbides, nitrides, sulfides, etc., can be used by vacuum deposition, sputtering, ion plating, ion beam assist, etc. A method of laminating a thin film in a layer or a multilayer, a method of laminating a resin having a different refractive index such as an acrylic resin or a fluororesin into a single layer or a multilayer can be used.

  In the present invention, when the antireflection layer is formed on the opposite side of the layer having the conductive pattern with the support of the electromagnetic wave shielding film interposed therebetween, the protective film is first formed after the antireflection layer is first formed. An embodiment in which the conductive pattern layer is formed after pasting is preferable. When the antireflection layer is formed after the conductive pattern is formed first, the efficiency of the plasma treatment and corona treatment performed to improve the adhesion between the antireflection layer and the support tends to be reduced. The embodiment in which the layer is formed first is preferred. In addition, when the antireflection layer is formed first, from the viewpoint of preventing the layer from being deteriorated by development, plating treatment, or the like, a mode in which a conductive pattern layer is formed after pasting a protective film in advance is preferable. .

  As the protective film used in the present invention, a commercially available protective film can be used. From the viewpoint of facilitating coating of a silver halide emulsion layer for forming a conductive pattern, the thickness of the film The thickness is preferably 10 to 100 μm, particularly preferably 20 to 60 μm. If the thickness is less than 10 μm, the rigidity of the film is remarkably reduced, so that the work efficiency of the protection film is likely to be lowered. If the thickness is more than 100 μm, a failure such as a winding reel tends to occur when the film is wound. is there.

  Although there is no restriction | limiting in particular in the kind of adhesive used for a protective film, The thing which does not damage an antireflection film at the time of peeling, without altering an antireflection film is used preferably. From such a viewpoint, an acrylic or silicone adhesive is preferably used. Moreover, as the adhesive force, what is 0.08-0.6N / 25mm is used preferably.

  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 "%" or "ppm" is used in an Example, unless otherwise indicated, "mass%" or "mass ppm" is represented.

Example 1
(Preparation of silver halide emulsion)
A silver chlorobromide emulsion (10 mol% silver bromide, 90 mol% silver chloride) was prepared by adding and mixing an aqueous silver nitrate solution and an aqueous potassium bromide and sodium chloride solution while controlling the solution to an aqueous gelatin solution at 35 ° C. did. In this emulsion, potassium rhodium bromide and potassium chloroiridate were added to a concentration of 1.0 × 10 ⁻⁷ (mol / mol silver), and Rh ions and Ir ions were doped. The silver / gelatin mass ratio was 4/1 (silver / gelatin volume ratio was about 0.5), and an alkali-treated low molecular weight gelatin having an average molecular weight of 40,000 was used as the gelatin species. The average particle size was 0.04 μm, and the variation coefficient of the particle size distribution was 0.13.

  Thereafter, 2.0 mg of sodium thiosulfate per mol of silver halide was used for chemical sensitization at 40 ° C. for 80 minutes, and after completion of chemical sensitization, 4-hydroxy-6-methyl-1,3,3a, 7- The silver halide emulsion was obtained by adding 500 mg of tetrazaindene per mole of silver halide and further adding 500 mg of the following sensitizing dye SD-1 per mole of silver halide.

(Support)
0% butyl acrylate: styrene: glycidyl acrylate (40: 20: 40%) latex is applied to one side of a transparent polyethylene terephthalate film support having a thickness of 120 μm, a width of 60 cm, and a length of 120 m. .40 g / m ² , hexamethylene-1,6-bis (ethylene urea) was applied so as to be 0.01 g / m ² to provide an undercoat layer. On one side, 0.20 g / m ^{2 of} gelatin was applied as a non-photosensitive intermediate layer.

Further, 0.20 g / m ^{2 of} gelatin was coated on the other side as a non-photosensitive intermediate layer.

(Coating of silver halide photosensitive layer)
To the above silver halide emulsion, a surfactant (disulfo oxalate, 2-ethylhexyl, sodium) is added as a coating aid to adjust the surface tension, and a hardener (tetrakis, vinylsulfonylmethyl, methane). Is added at a rate of 20 m so that the silver coating amount is 0.60 g / m ² and the gelatin coating amount is 0.15 g / m ^2. The coating was carried out at a speed of / min and dried to prepare a roll-shaped silver halide photosensitive material.

(exposure)
The silver halide photosensitive material thus obtained was exposed with a mesh pattern as shown in FIG. The mesh portion has a lattice shape with a line width of 10 μm and a line interval of 240 μm, and the lattice lines are formed at an angle of 45 degrees with respect to the longitudinal direction of the roll.

  These electromagnetic wave shielding mesh patterns were exposed using a laser beam having an oscillation wavelength of 440 nm (blue semiconductor laser diode manufactured by Nichia Corporation) while continuously conveying the silver halide photosensitive material.

(Development processing)
The exposed sample was subjected to development processing at 25 ° C. for 60 seconds using the following developing solution using an automatic development processing / physical development / plating integrated machine of a leader belt conveyance system having a width of 60 cm as shown in FIG. Thereafter, using the following fixing solution, a fixing process was performed at 25 ° C. for 120 seconds, followed by a water washing process. Furthermore, after performing physical development at 25 ° C. for 5 minutes using the following physical developer, followed by washing with water, electrolytic plating at 25 ° C. for 5 minutes at 2.5 A / cm ² with the following copper plating solution. Went and washed with water. Finally, it dried with 60 degreeC warm air, and produced the elongate roll-shaped electromagnetic wave shielding film samples 101-107.

(Developer)
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 (fixing solution)
750 ml of pure water
Sodium thiosulfate 250g
Anhydrous sodium sulfite 15g
Glacial acetic acid 15ml
Potash alum 15g
Add water to make 1 liter (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
1mol / L hydrochloric acid 2.0ml
Add water to bring the total volume to 1 liter.

  Here, the copper plating solution is a copper plating solution 1 using commercially available copper sulfate, a copper plating solution 2 from which Fe content contained as impurities is removed up to 80 ppm, and further purified by recrystallization to have a purity of 99.99%. Copper plating solutions 4 to 7 for preparing the copper plating solution 3 using the copper sulfate and further examining impurities by intentionally adding impurities to the copper plating solution 3 were prepared and used.

Copper plating solution 1: Use of commercially available copper sulfate reagent (purity 98%) Copper plating solution 2: Fe was removed from commercially available copper sulfate reagent to make Fe content 80 ppm with respect to Cu Copper plating solution 3: Purified sulfuric acid Copper (purity 99.99%) used Copper plating solution 4: Fe was added to purified copper sulfate, and Fe content was 50 ppm with respect to Cu Copper plating solution 5: Si was added to purified copper sulfate, Cu Copper plating solution 6 with Si content of 20 ppm relative to Cu: Ca was added to purified copper sulfate, and Ca content rate was 5 ppm with respect to Cu. Copper plating solution 7: Mg was added to purified copper sulfate, Cu Mg content is 5 ppm (Evaluation)
Thus, the following evaluation was performed with respect to the electromagnetic wave shield film samples 101-107 which have the electroconductive metal mesh part obtained.

<Spot defect>
The mesh of the plated electromagnetic wave shielding film was observed with a loupe, and the number of spots per 100 cm ² was counted. About each sample, it measured about six places per 100 cm < ² >, the arithmetic mean value was obtained, and the following reference | standard evaluated.

A: 0 or 1 B: 2 to 5 C: 6 or more <Plating unevenness>
After the plating treatment and drying, the pattern unevenness in the vicinity of the border between the frame part and the mesh part of the sample was photographed at several points with a high-definition CCD camera and magnified 200 times on a 40-inch monitor screen. And visually observed and evaluated according to the following criteria.

A: No variation in the line width of the mesh is observed. B: A slight variation in the line width of the mesh is observed. C: A portion where the line width is 1/2 or less or a disconnection portion is recognized. Show.

  From Table 1, in the electrolytic copper plating on the developed silver mesh, the occurrence of spot defects was reduced by removing impurities Fe and Si in the copper sulfate. Moreover, plating unevenness was reduced by removing Ca and Mg. By intentionally adding impurities to high purity copper sulfate, their effects were found.

Example 2
To the copper plating solution 3 prepared in Example 1, silver nitrate was added to prepare copper plating solutions 8 to 12 having a silver concentration shown in Table 2. Using this copper plating solution and the copper plating solution 3, Example 1 was prepared. In the same manner as described above, spot defects and plating unevenness were evaluated. Furthermore, adhesiveness and discoloration were evaluated by the following methods.

<Adhesiveness>
After plating treatment, each dried sample is allowed to stand in an atmosphere of 23 ° C. and 55% RH for 24 hours, and then the adhesion between the silver mesh and the copper plating is evaluated on the plating surface according to the JIS-K5400 cross-cut adhesion test method. It was.

  A cross-shaped cut line was drawn for each sample, and cellophane tape No. 1 manufactured by Nitto Denko Corporation was used. 29 was affixed, the tape was peeled off, the peeled state of the silver mesh and the copper plating was examined, and the following criteria were evaluated.

A: Peeling of silver mesh and copper plating does not occur and copper plating is strong B: Peeling of silver mesh and copper plating is slightly observed in a part of the cross cut part C: Silver mesh and copper plating Is observed at 20% or more <Discoloration>
The plated electromagnetic wave shielding film was left in an atmosphere of 70 ° C. and 25% RH for 1000 hours, and the discolored state of the mesh was visually evaluated as follows.

A: Not recognized at all B: Slightly recognized, but no problem in practical use C: Discoloration observed D: Significant blackening discoloration is shown in Table 2.

  From the results in Table 2, it was found that when silver was present in the copper plating solution, peeling of the silver mesh and the copper plating hardly occurred, and discoloration in the durability test of the electromagnetic wave shielding film could be reduced. In addition, when the amount of silver was increased to 150 ppm, there was a tendency for the plating rate to decrease slightly.

Example 3
Using the copper plating solution 3 prepared in Example 1, copper plating was continuously carried out while continuously transporting a long roll-shaped developed sample. When the plating was continued by replenishing only the concentrated aqueous solution of purified copper sulfate with respect to the decrease of the copper ions in the copper plating solution, the silver ions in the copper plating solution became 10 ppm. When the same evaluation as in Example 2 was performed on the plated portion of the sample 301 at this time, the same excellent effect as in Example 2 was reproduced.

  Next, the copper plating solution was replenished with various combinations of copper ion and silver ion concentrations, replenishment amount, overflow amount, solution temperature, and stirring state.

  As a result, in continuous copper plating of a long roll sample, it is preferable to replenish the liquid so that the amount of silver ions is also kept constant in addition to keeping the copper ions in the copper plating solution constant. That is, it is preferable to add silver ions to the copper plating solution at the start of copper plating, that the replenisher of the copper plating solution preferably contains silver ions, and the silver ions in the copper plating solution are When the amount is too high, it is found preferable to replenish the copper plating solution replenisher with little or no silver ions and to detect and control not only the copper ions in the copper plating solution but also the amount of silver ions. It was.

Example 4
In Example 2, a copper plating solution was prepared by replacing the purified copper sulfate with high-purity copper sulfate “Iupinogue” manufactured by Nikko Cs Chemical Co., Ltd., and the same test was performed.

  As a result, even when high-purity copper sulfate is used, the effect of the present invention is obtained as in the case of the purified copper sulfate, and the effect of the present invention is remarkable when the amount of silver ions is in the range of 0.1 to 100 ppm. I understood that.

Example 5
In Examples 2 to 4, instead of silver chlorobromide having an average grain size of 0.04 μm as silver halide, silver iodide, silver bromide, silver iodobromide, silver chloride, chloroiodine having an average grain size of 0.04 μm A similar test was conducted using silver halide and silver chloroiodobromide. As a result, silver halide containing silver chloride, that is, silver chloride, silver chlorobromide, silver chloroiodide, silver chloroiodobromide, and silver mesh formed by electrolytic copper plating of the silver mesh, the effect is large, especially silver chloride It was found that the content was remarkable at 70 mol% or more.

Example 6
In Examples 2-5, as a result of analyzing the mesh surface of the electromagnetic wave shielding film showing the remarkable effect of the present invention by fluorescent X-ray analysis using an electron microscope, metallic silver is present in spots on the copper plating surface. I understood. When silver is present in the copper plating solution, silver is also present on the surface of the copper plating, which is considered to be related to the excellent effect of the present invention.

It is a figure which shows an exposure pattern. It is the schematic which shows the process of an automatic image development processing / physical image development / plating integrated machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mesh part 2 Frame part 11 Development 12 Fixing 13 Washing 14 Physical development 15 Plating 16 Drying

Claims (11)

An electromagnetic wave in which a silver halide photosensitive material having a transparent support is exposed to light and developed to form a metal silver mesh portion, and the metal silver mesh portion is further subjected to copper plating to form a highly conductive mesh portion. In the manufacturing method of a shield film, the copper sulfate used for this copper plating process is a refined copper sulfate whose iron (Fe) content rate is 100 ppm or less, 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 iron sulfate (Fe) content of the copper sulfate is 50 ppm or less with respect to copper (Cu). 3. The method for producing an electromagnetic wave shielding film according to claim 1, wherein the copper sulfate has a silicon (Si) content of 20 ppm or less with respect to copper (Cu). The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 3, wherein a content of at least one of Ca and Mg of the copper sulfate is 5 ppm or less with respect to copper (Cu). . The said copper sulfate is high purity copper sulfate of purity 99.99% or more, The manufacturing method of the electromagnetic wave shielding film of any one of Claims 1-4 characterized by the above-mentioned. The electromagnetic wave shield according to any one of claims 1 to 5, wherein a copper plating solution used for the copper plating treatment contains 0.1 to 100 ppm of silver (Ag) with respect to copper (Cu). A method for producing a film. The method for producing an electromagnetic wave shielding film according to claim 1, wherein the copper plating obtained by the copper plating treatment is electrolytic copper plating. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 7, wherein the development processing comprises chemical development processing, fixing processing, and physical development processing. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 8, wherein the electromagnetic wave shielding film is continuously produced by a long roll having a width of 50 cm or more. The method for producing an electromagnetic wave shielding film according to any one of claims 1 to 9, wherein the silver halide of the silver halide photosensitive material contains 70 mol% or more of silver chloride. An electromagnetic wave shielding film having a highly conductive mesh portion formed by copper plating on the surface of a silver mesh on a transparent support, wherein Ag is present on the surface of the highly conductive mesh portion. Shield film.

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