JP2009038078A - Electromagnetic wave shield film, and plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic wave shield film which has excellent image sharpness and color tones, small moire, high adhesion to a metal grid, a short intensification time, and excellent coating property while maintaining high electromagnetic shield performance, and to provide a plasma display panel using the same. <P>SOLUTION: After a silver halide sensitive material having a photosensitive layer containing silver halide and a binder on a base is pattern-exposed, black-and-white development and intensification processing are carried out to manufacture the electromagnetic wave shield film having metal arranged in a grid shape, wherein a line width of the metal grid is 3 to 20 μm, a numerical aperture is 80 to 95%, and a standard deviation in inter-metal-grid distance is 0.1 to 1.3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electromagnetic wave shielding film and a plasma display panel.

  In recent years, there have been increasing opportunities to use electronic devices such as display devices used in mobile phones, personal computers, TVs, etc., but electromagnetic waves are generally emitted from these electronic devices, so that It is known that so-called electromagnetic interference (EMI) occurs, such as malfunction of 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, equipment that requires visibility such as a CRT, a flat panel display, or a window glass needs to satisfy both electromagnetic wave shielding performance and transparency.

  So far, in the case of producing an electromagnetic wave shielding film, photolithography etching, and recently, a combination of inkjet and plating has been known. In recent years, regarding a transparent conductive film for electromagnetic wave shielding, it is desired to achieve both electromagnetic wave shielding ability and transparency with a finer mesh. However, the current situation is that pattern accuracy cannot easily catch up with inkjet and printing. Further, in photolithography etching, the manufacturing process is complicated and the cost is high.

  Further, from the viewpoint of safety, a high electromagnetic shielding ability is essential, and an inexpensive film having an advanced electromagnetic shielding ability is desired.

  Therefore, the silver salt method has been attracting attention as an inexpensive shield film, and a fine pattern can be produced without increasing the intersection. However, in the silver salt method, in order to impart conductivity, plating is usually performed after development, and the metal grid adhesion and moire interference fringes at that time are problematic.

  As a countermeasure, Patent Document 1 discloses a method of preventing the moire interference fringes by setting the line width of the metal grating to 1 to 20 μm and the aperture ratio to 56 to 96% to balance the shielding ability and the image sharpness. . However, this condition is not sufficient for current plasma display panels. In addition, the standard deviation of the metal grid and the number of disconnected parts are not mentioned.

Patent Document 2 discloses a method for preventing moire by reducing the line width of a metal lattice to 15 μm or less by etching. However, this condition is not sufficient. Further, there is no description on image sharpness, and the standard deviation of the metal grid and the number of disconnected parts are not mentioned.
JP 11-317593 A JP 2001-343520 A

  The present invention has been made in view of the above problems, and its purpose is to maintain a high electromagnetic shielding ability while maintaining good image sharpness and color tone with less moire, high adhesion of a metal grid, and intensification. An object of the present invention is to provide an electromagnetic wave shielding film having a short time and good coatability, and a plasma display panel using the same.

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

  1. In an electromagnetic wave shielding film in which a silver halide photosensitive material having a photosensitive layer containing a silver halide and a binder on a support is subjected to pattern exposure, black-and-white development and intensification processing are performed, and metal is arranged in a lattice shape An electromagnetic wave shielding film, wherein the line width of the metal grid is 3 to 20 μm, the aperture ratio is 80 to 95%, and the standard deviation of the distance between the metal grids is 0.1 to 1.3.

  2. 2. The electromagnetic wave shielding film as described in 1 above, wherein the metal grating has a line width of 3 to 14 μm.

3. 3. The electromagnetic wave shielding film as described in 1 or 2 above, wherein the silver halide photosensitive material has a silver halide coating amount of 0.3 to 3.0 g / m ² in terms of metallic silver.

  4). 4. The electromagnetic wave shielding film according to any one of 1 to 3, wherein the photosensitive layer has a thickness of 0.03 to 0.3 μm.

  5). 5. The electromagnetic wave shielding film as described in any one of 1 to 4, wherein the photosensitive layer has a silver halide / binder volume ratio of 0.2 to 0.8.

  6). The cross-sectional area S of the metal grid satisfies the relationship of 0.85 ≦ S / (W × H) ≦ 1.0 with respect to the line width W and the line height H. The electromagnetic wave shielding film of any one of Claims 1.

7). 7. The electromagnetic wave shielding film according to any one of the above 1 to 6, wherein the number of disconnection portions of the metal lattice per 1 m ^{2 in} the surface direction of the electromagnetic wave shielding film is 1 to 100.

  8). The electromagnetic wave shielding film according to any one of 1 to 7, wherein the intensifying treatment is physical development.

  9. 8. The electromagnetic wave shielding film as described in any one of 1 to 7, wherein the intensifying treatment is performed after physical development.

  10. 10. The electromagnetic wave shielding film as described in 8 or 9 above, wherein the physical developer used for the physical development is acidic.

  11. A plasma display panel comprising the electromagnetic wave shielding film according to any one of 1 to 10 above.

  According to the present invention, an electromagnetic wave shielding film having excellent image sharpness, color tone, less moire, high adhesion of a metal grid, short intensification time, and good coatability while maintaining high electromagnetic wave shielding ability. A plasma display panel using can be provided.

  As a result of studying the above problems, the inventors of the present invention prepared a silver halide photosensitive material having a photosensitive layer containing a silver halide and a binder on a support by performing black-and-white development and intensification processing after pattern exposure. In the electromagnetic wave shielding film in which the metal is arranged in a lattice shape, the line width of the metal lattice is 3 to 20 μm, the aperture ratio is 80 to 95%, and the standard deviation of the distance between the metal lattices is 0.1 to 1.3. As a result, it was confirmed that the shielding ability improved dramatically.

  That is, in order to obtain a high shielding ability, it is not sufficient to adjust the line width and aperture ratio of the metal grid within a specific range, and the standard deviation of the distance between the metal grids should be 1.3 or less. is necessary. Conventionally, it has been difficult to obtain such a standard deviation. However, the present inventors have changed the exposure method from conventional laser exposure to exposure using a lattice-like photomask, thereby reducing a metal lattice of 1.3 or less. A standard deviation of the distance was achieved. In addition, it is not preferable from a cost viewpoint to make the standard deviation of the distance between metal lattices less than 0.1.

  In the silver salt method, it is presumed that the conductivity inside the metal grid line is high because it is made by intensifying treatment based on metal silver, and the shielding ability is related to the relationship between the line width and the distance between the metal grids. I think it can be controlled.

  In addition, this relational expression contributes to the achievement of a high transmittance and maintains a high potential as an electromagnetic wave shielding film for a plasma display panel.

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

(Support)
In the present invention, a normal synthetic resin film can be used as the 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 plasma display, high transparency is required. Therefore, it is desirable that the support itself has high transparency. The average transmittance in the visible light region of the plastic film or glass plate as the support in this case 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 of 400 to 700 nm at least every 5 nm, and obtaining the average value thereof. Define. 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.

(Metal grid)
In the present invention, the conductive metal grid formed to shield electromagnetic waves has a line width of 3 to 20 μm, an aperture ratio of 80 to 95%, and a standard deviation of the distance between the metal grids of 0.1 to 1. 3 is a feature. The line width of the metal grid and the distance between the metal grids are measured with a microscope. As for the standard deviation of the distance between the metal grids, the metal grid distance is measured at 100 points at random, and the standard deviation of the measured values is calculated.

  The definition of the aperture ratio is to maintain the shielding ability while maintaining the clearness of the display panel image, and the standard deviation of the inter-lattice distance is because the shielding ability can be different when the distance is shifted. In a range where the standard deviation is small, the shielding ability is very high, and if there is a variation, electromagnetic waves leak from the misaligned part, and the shielding ability may be lowered.

  The line width of the metal grid is 3 to 20 μm in the present invention. If it exceeds 20 μm, when the aperture ratio of 80 to 95% of the present invention is maintained, the area of the lattice becomes too large and the shielding ability cannot be maintained. From the viewpoint of making the lattice inconspicuous, it is preferably 18 μm or less, and more preferably 14 μm or less. When the line width is 14 μm or less, the moire suitability is high and the electromagnetic wave shielding ability can be compatible. When the aperture ratio and standard deviation are maintained, a high shielding ability can be obtained if the line width is 14 μm or less. 10 μm or less is most preferable. If it is less than 3 μm, the conductivity is slightly insufficient.

  The line spacing of the metal grid is preferably 150 μm or more, more preferably 180 μm or more, and particularly preferably 200 μm or more. Moreover, 0.1-25 micrometers is preferable, as for the thickness of a lattice fine wire, 0.2-20 micrometers is more preferable, and 0.5-15 micrometers is especially preferable.

  In the present invention, the standard deviation of the distance between the metal lattices is 0.1 to 1.3. When the standard deviation is less than 0.1, a cost is required for realistic stable production, and when it exceeds 1.3, the shielding ability is greatly deteriorated.

  The aperture ratio of the metal lattice in the present invention is 80 to 95%. From the viewpoint of visible light transmittance, the aperture ratio is preferably greater than 80%, more preferably 85% or more, and most preferably 90% or more. If the aperture ratio exceeds 95%, it is difficult to maintain the shielding ability. If the aperture ratio is less than 80%, the sharpness of the image cannot be maintained. The aperture ratio is the ratio of the portion without the fine lines forming the grid to the whole. For example, the aperture ratio of a square grid-like grid having a line width of 10 μm and an inter-lattice distance of 200 μm is 90%.

  In the present invention, in order to provide high translucency and high electromagnetic wave shielding performance, a grid-like fine wire grid pattern is drawn by exposure, followed by black-and-white development processing and intensification processing, thereby providing a conductive grid pattern. It is preferable to form an electromagnetic wave shielding film.

  In the present invention, it is preferable to provide a frame portion in contact with the metal grid in order to ground the current generated by absorbing electromagnetic waves with the metal grid. The frame portion generally forms a strip-shaped frame in order to improve conductivity.

  In the present invention, it is preferable that the conductivity of the frame portion is higher than that of the metal grid. For this purpose, the aperture ratio is made smaller than the metal grid, the pitch is made smaller than the metal grid, and the line width is made larger than that of the metal grid. Increasing the thickness, increasing the thickness of the fine wire than the metal grid, and the like. The aperture ratio of the frame metal lattice is preferably 10 to 80%, more preferably 10 to 70%. If it is less than 10%, the effect of the present invention is small, and if it is more than 80%, the grounding property is insufficient.

(Method of forming metal grid)
In the electromagnetic wave shielding film of the present invention, a method for forming a conductive metal lattice having an electromagnetic wave shielding function uses a silver salt photographic method in which a silver halide photosensitive material is formed by exposure, development processing and intensification processing. At this time, as described above, in order to achieve the standard deviation of the distance between the metal grids, it is desirable that the exposure is performed using a grid-like photomask. Conventionally, a laser exposure machine is often used, but as a result of the study by the present inventors, the exposure head is a set of a plurality of units in the laser exposure machine, adjustment of each unit, and adjustment between units is difficult, It was found that the distance between the metal lattices was likely to vary.

  In addition, it is desirable for thinning to apply a thin emulsion layer and to carry out intensification processing by physical development. Since physical development adheres to chemically developed silver with very high selectivity, it can be applied with a small amount of chemically developed silver, the emulsion layer can be thinned, and the line width caused by exposure blurring can be increased. Can be suppressed. Moreover, since only silver particles accumulate, it is easy to ensure conductivity with a small amount, and the expansion of the line width due to the intensification process can be suppressed. In order to ensure conductivity only by chemical development, it is necessary to increase the cross-sectional area of the developed silver line by coating the emulsion layer thickly in consideration of conductivity inhibition by the binder between the developed silver particles. This method is easy to blur lines by exposure and is not suitable for thinning. In addition, electroless plating is generally used as a supplementary treatment other than physical development, but the selectivity to developed silver after chemical development is low, and not only the lines are blurred, but the plating tends to adhere to unexposed areas. This is also unsuitable for thinning.

  When preparing the electromagnetic wave shielding film of the present invention, a photosensitive layer containing a silver halide and a binder, which will be described later, is provided on the support. In addition to this, the photosensitive layer includes a hardening agent, a thickening agent, an activity. An agent etc. can be contained.

(Silver halide)
In the present invention, the coating amount of silver halide is preferably 0.3 to 3 g / m ² in terms of silver, and more preferably from 0.3 to 1 g / m ² in terms of silver. In this range, the target electromagnetic wave shielding film can be produced without increasing the metal grid line width.

When the silver halide content is less than 0.3 g / m ² , it is difficult to perform efficient intensification treatment and it is difficult to obtain sufficient electromagnetic wave shielding performance. This is presumably 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 lattice. If it exceeds 3 g / m ² , the intensification process is possible, but the sharpness of the grid lines themselves is lost. Along with this, the aperture ratio decreases and the sharpness of the display panel image decreases. In addition, since the amount of silver halide relative to the binder is relatively large, the coating tends to become brittle and it is difficult to maintain sufficient coating strength. The silver halide coating amount is calculated by analyzing the silver amount of the coated sample.

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

In the present invention, the amount of binder in the silver halide photosensitive material is particularly preferably 10 to 0.2 g / m ² 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 0.2 g / m ² , the distance between 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 lattice. Further, durability against changes in temperature and humidity becomes insufficient, and the effects of the present invention cannot be obtained.

  In the present invention, the silver halide / binder volume ratio of the photosensitive layer is preferably 0.2 to 0.8. This is to increase the contact area between the developed silver grains as described above, and not only dramatically improve the emulsion coating property but also the relatively high binder ratio, so even if the line width is small, the metal lattice Good adhesion. If it is less than 0.2, it will be very difficult to apply the reinforcement processing after black-and-white development, leading to an increase in cost. If it exceeds 0.8, the coating property to the base is poor and the unevenness of the emulsion film tends to be formed. Therefore, the conductive irregularity of the lattice is easily generated, and the shielding ability is likely to be lowered. The silver halide / binder ratio is calculated by conducting a silver amount analysis on a reference volume of the coated sample.

  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 grains having high sensitivity are preferable, and silver iodobromide grains are preferably used. When a large amount of iodine is contained, the sensitivity is high and the particles can be made fine.

  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, and in that 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, the value obtained by dividing the coating silver amount (g / m ² ) by the particle size (μm) is preferably 6 to 25. 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 is reduced, so that the conductivity tends to be lowered. This is because it becomes a trend.

  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 photosensitive layer according to the present invention (a layer comprising at least silver halide and a binder), silver halide grains are uniformly dispersed, and the silver halide grains are supported on a support, and a silver halide photosensitive layer and A binder is used for the purpose of ensuring adhesion to other layers or the support. 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 silver halide 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 Hydrophilic colloids such as synthetic hydrophilic polymer materials such as derivatives, mono- or copolymers can also be used.

  Moreover, it is preferable that the film thickness of a photosensitive layer is 0.03-0.3 micrometer. If it is less than 0.03 μm, the adhesion of the metal grid to the support is poor, and it tends to peel off. If it exceeds 0.3 μm, color is likely to be formed due to interference of the binder film, resulting in poor color tone. The film thickness of the photosensitive layer is measured by cutting a coated sample and enlarging a cross section with a microscope.

(Layer structure of silver halide photosensitive material)
The layer structure of the silver halide photosensitive material used for forming the electromagnetic wave shielding film of the present invention basically comprises a support and a 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 photosensitive layer, a backing layer is provided on the opposite side of the support from the silver halide photosensitive layer, or protection is provided on the photosensitive layer. It is preferable to provide a layer. These layers may be composed of a plurality of layers.

  In the present invention, it is also preferable to provide a photosensitive layer on each side 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 becomes possible to create 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)
In the method for producing an electromagnetic wave shielding film of the present invention, a silver halide photosensitive material in which a photosensitive layer comprising at least silver halide and a binder is coated on a support is subjected to patterning exposure, development processing and intensification processing. A continuous conductive metal grid and a frame portion are formed.

  Therefore, basically, (1) a step of forming a silver halide photosensitive material by coating a silver halide emulsion on a support, (2) a step of pattern exposing the silver halide photosensitive material, and (3) exposure. A process for developing a processed silver halide light-sensitive material, and (4) a step for intensifying a silver halide light-sensitive material that has been subjected to a development process. Steps, drying and aging the applied silver halide photosensitive material, physical development before intensifying the developed silver halide photosensitive material, stabilization processing such as pressure heating after intensification processing You may provide the process to do.

  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 shielding film may be obtained as a long roll, or may be cut into a required size and accumulated 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 dip coating, spray coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, inkjet coating, or US Pat. No. 2,681,294. Examples include an extrusion coating method using the 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 and reinforcement processing (physical development and / or plating processing) described later. Examples of the light source used for exposure include light such as ultraviolet rays, visible rays, and infrared rays, and radiation such as electron beams and X-rays. Visible rays are used in terms of utilizing the characteristics of silver halide. Is preferred. 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 particular, in the present invention, exposure is preferably performed using a lattice-like photomask. The light source is preferably blue light or UV light because of the photosensitive properties of silver halide.

(Development processing)
In the present invention, after the silver halide photosensitive material is exposed, development processing (monochrome development) is performed. The development process is 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 present invention, in order to make the frame portion more conductive than the metal grid, it is possible to accelerate the development processing reaction in the region corresponding to the frame portion during the development processing of the silver halide photosensitive material. Specifically, this is achieved by increasing the liquid temperature in the vicinity of the frame portion equivalent region or increasing the liquid agitation in the vicinity of the frame portion equivalent region in the developing solution. Needless to say, in the portion where the development processing reaction is promoted, the silver development rate is increased and more developed silver is formed than the metal lattice, and a frame lattice having a large line width and thickness can be formed.

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

(Physical development processing)
Physical development can be performed by immersing a silver halide photosensitive material 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, by performing physical development after black and white development, higher electromagnetic wave shielding ability and adhesion of the metal grid can be maintained. Further, by keeping the physical developer acidic, it is possible to amplify the conductivity of the metal lattice with higher selectivity and maintain the life of the solution.

(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 performed alone or in combination. Among these, 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 process 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, an aspect in which the amount of metal applied by physical development or metal plating is 10 to 100 times in terms of mass with respect to developed silver obtained by exposing and developing a silver halide photosensitive material. preferable. This value can be determined by quantifying the metal contained in the silver halide light-sensitive 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 with respect to developed silver obtained by exposing and developing a silver halide photosensitive material, 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 lattice pattern portion. In the present invention, it is preferable to perform both physical development and metal plating.

  The cross-sectional area S of the metal lattice preferably satisfies the relationship of 0.85 ≦ S / (W × H) ≦ 1.0 with respect to the line width W and the line height H. Within this range, it was found that a wide viewing angle could be obtained when the plasma display was adopted while maintaining the electromagnetic wave shielding ability. When S / (W × H) is less than 0.85, glare is observed when the lattice is viewed from the front. On the other hand, when S / (W × H) exceeds 1, the transmittance decreases when the lattice is viewed obliquely.

  The cross-sectional area, line width, and line height of the metal grid are measured by cutting the metal grid line and enlarging the cross section with a microscope.

It is preferable that the number of disconnection parts of the metal grid per 1 m ² of the surface direction of the electromagnetic wave shielding film is 1 to 100. From the function of the electromagnetic wave shield, the number of broken portions of the metal grid per 1 m ² is allowed up to 100, and high shielding ability can be maintained. From the viewpoint of the shielding ability, the number of disconnected parts is preferably 0. However, in the case of 0, it is difficult to maintain production stability, resulting in an increase in cost. On the other hand, if it exceeds 100, the shielding ability tends to decrease. The number of disconnections is measured with a microscope for all 1 m ² lattice samples.

  Furthermore, in the present invention, pressurization, heating, or heating after pressurization can be performed in order to increase conductivity.

  The pressure is 1 kPa to 100 MPa, preferably 10 kPa to 10 MPa, and more preferably 50 kPa to 5 MPa. If the pressure is less than 1 kP, the effect of improving the conductivity is small, and if it is greater than 100 MPa, it is difficult to keep the surface smooth, and haze increases.

  The heating is 40 to 300 ° C, preferably 50 to 200 ° C, more preferably 60 to 200 ° C. If it is less than 40 ° C., the effect of improving conductivity is small, and if it is higher than 300 ° C., it is difficult to keep the surface smooth.

(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 treatment is preferably performed after completion of the development treatment and before the plating treatment because the transmittance can be efficiently improved in a short time treatment, and particularly preferably after completion of the physical development.

(Blackening treatment)
In the present invention, it is preferable to perform a blackening treatment on the surface of the metal grid 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 plasma display panel (plasma display panel), for example, it is possible to reduce a decrease in contrast due to reflection of external light and It is preferable because the color tone can be kept black and high quality. 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, potassium pyrophosphate, A method of blackening by immersion in an aqueous solution containing ammonia and 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, it is also preferable to provide a near infrared absorbing layer that is a layer containing a near infrared absorbing dye below the photosensitive layer. . In some cases, the near-infrared absorbing layer may be provided on the opposite side of the support from the side having the photosensitive layer, or may be provided on both the photosensitive layer side and the opposite side. A near-infrared absorbing layer can be provided between the photosensitive 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 photosensitive layer. The former is preferred because it can be applied simultaneously with one side.

  Specific examples of near-infrared absorbing dyes include polymethine, phthalocyanine, naphthalocyanine, metal complex, aminium, imonium, diimonium, anthraquinone, dithiol metal complex, naphthoquinone, indolephenol, azo And triallylmethane-based compounds. The optical filters for plasma display panels are required to absorb near infrared rays mainly for heat ray absorption 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, manufactured by Nippon Kayaku Co., Ltd.), and nickel dithiol complex compounds are SIR-128, SIR-130, SIR-132, SIR-159. , SIR-152, SIR-162 (manufactured by Mitsui Chemicals, Inc.), and phthalocyanine compounds may be commercially available products such as IR-10, IR-12 (manufactured by Nippon Shokubai Co., Ltd.).

  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, light near 595 nm is used to prevent a decrease in color reproducibility due to emission lines of neon gas used in the plasma display panel. It preferably contains an absorbing dye. 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, in order to avoid deterioration of the electromagnetic wave shielding film due to ultraviolet rays, it is preferable to use an ultraviolet absorber having a maximum absorption wavelength of less than 350 nm.

  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. Although there is no restriction | limiting in particular about the addition layer of these ultraviolet absorbers, From a viewpoint of preventing the deterioration by the ultraviolet-ray of the binder used for a silver halide photosensitive layer (lattice pattern layer), addition to a silver halide photosensitive layer Alternatively, it is preferably provided on the light source side of the layer.

  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, it is also preferably used to add these ultraviolet absorbers directly to the support. In this case, for example, the embodiment described in JP-T-2004-531611 can also be preferably used.

(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 antireflection layer is preferably composed of a plurality of light transmissive layers having different refractive indexes, and more preferably composed of a high refractive index layer, a medium refractive index layer, and a low refractive index layer containing inorganic fine particles. 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 transparent electromagnetic wave shielding film of 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 sandwiched, after the antireflection layer is first formed, It is preferable to bond a protective film and then form a conductive pattern layer. 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. It is preferred to form the layer first. In addition, when the antireflection layer is formed first, it is preferable to form a conductive pattern layer after pasting a protective film in advance from the viewpoint of preventing the layer from being deteriorated by development, plating treatment or the like. .

  As the protective film used in the present invention, a commercially available protective film can be used, but from the viewpoint of easy application of a photosensitive layer for forming a conductive pattern, the thickness of the film is 10-100 micrometers is preferable, Most preferably, it is 20-60 micrometers. 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. Various conditions in the following embodiments can be appropriately changed without departing from the features and spirit of the present invention, and the scope of the present invention should not be construed as being limited by the following examples. 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
[Production of photosensitive material]
(Preparation of silver halide emulsion)
The following solution A was kept at 34 ° C. in the reaction vessel, and the pH was adjusted to 2.95 using nitric acid (6%) while stirring at high speed using the mixing and stirring device described in JP-A-62-2160128. did. 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 (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
Next, after the silver halide emulsion is heated to 60 ° C., a predetermined amount of spectral sensitizing dye SD-1 is added as a solid fine particle dispersion, and then adenine, ammonium thiocyanate, chloroauric acid and thiosulfuric acid are added. A mixed aqueous solution of sodium and a dispersion of triphenylphosphine selenide were added, and after 60 minutes, a silver iodide fine grain emulsion was added, followed by ripening for a total of 2 hours. At the end of aging, a predetermined amount of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (TAI) was added as a stabilizer.

  In addition, said additive and its addition amount (per mol of AgX) are shown below.

5,5'-Dichloro-9-ethyl-3,3'-di- (sulfopropyl)
-Oxacarbocyanine sodium salt anhydride 2.0 mg
5,5'-di- (butoxycarbonyl) -3,3'-di- (4-sulfobutyl) -benzimidazolocarbocyanine sodium salt anhydrous 120 mg
Adenine 15mg
Potassium thiocyanate 95mg
Chloroauric acid 2.5mg
Sodium thiosulfate 2.0mg
Triphenylphosphine selenide 0.4mg
Silver iodide fine particles 280mg
4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (TAI)
500mg
A solid fine particle dispersion of spectral sensitizing dye was prepared by the following method. That is, it was obtained by adding a predetermined amount of the spectral sensitizing dye to water previously adjusted to 27 ° C. and stirring at 3,500 rpm for 30 to 120 minutes with a high-speed stirrer (dissolver).

  A dispersion of the above selenium sensitizer was prepared as follows. That is, 120 g of triphenylphosphine selenide was added to 30 kg of ethyl acetate at 50 ° C., stirred, and completely dissolved. On the other hand, 3.8 kg of photographic gelatin was dissolved in 38 kg of pure water, and 93 g of 25% aqueous solution of sodium dodecylbenzenesulfonate was added thereto. Next, these two liquids were mixed and dispersed at a dispersion blade peripheral speed of 40 m / sec for 30 minutes at 50 ° C. with a high-speed stirring disperser having a dissolver having a diameter of 10 cm. Thereafter, the ethyl acetate was removed while rapidly stirring under reduced pressure until the residual concentration of ethyl acetate became 0.3% by mass or less. Thereafter, this dispersion was diluted with pure water to make 80 kg. A portion of the dispersion thus obtained was collected and used in the above experiments.

  The average iodine content of the outermost surface of the silver halide grains contained in the silver halide grain emulsion by the addition of the silver iodide fine grains was about 4 mol%.

  Next, the following additives were added to the emulsion thus sensitized to prepare a photosensitive layer coating solution. At the same time, a protective layer coating solution was also prepared.

Next, a photosensitive layer coating solution (the coating silver amount is 1.0 g / m ² ) and a protective layer coating solution are applied simultaneously on one side of a subbed polyethylene terephthalate film base (thickness of 175 μm) and dried. Photosensitive materials 101 to 117 were obtained.

(Photosensitive layer coating solution)
The following various additives were added to the emulsion obtained above.

2,6-bis (hydroxyamino) -4-diethylamino-1,3,5-triazine
5 mg / m ²
t-Butyl-catechol 130 mg / m ²
Polyvinylpyrrolidone (molecular weight 10,000) 35 mg / m ²
Styrene-maleic anhydride copolymer 80 mg / m ²
Sodium polystyrene sulfonate 80mg / m ²
Trimethylolpropane 350mg / m ²
Diethylene glycol 50mg / m ²
Nitrophenyl-triphenyl-phosphonium chloride 20 mg / m ²
1,3-dihydroxybenzene-4-ammonium sulfonate 500 mg / m ²
2-Mercaptobenzimidazole-5-sulfonic acid sodium salt 5 mg / m ²
_{n-C 4 H 9 OCH 2} CH (OH) CH 2 N (CH 2 COOH) 2 350mg / m 2
Colloidal silica 0.5g / m ²
Dextrin (average molecular weight 1000) 0.2 g / m ²
However, the gelatin was adjusted to 1.0 g / m ² .

(Protective layer coating solution)
Gelatin 0.8g / m ²
Matting agent composed of polymethyl methacrylate (Area average particle size 7.0 μm)
50 mg / m ²
Formaldehyde 20mg / m ²
2,4-dichloro-6-hydroxy-1,3,5-triazine sodium salt
10 mg / m ²
Bis-vinylsulfonylmethyl ether 36 mg / m ²
Polyacrylamide (average molecular weight 10,000) 0.1 g / m ²
Sodium polyacrylate 30mg / m ²
Polysiloxane 20mg / m ²
_{C 9 F 19 -O- (CH 2} CH 2 O) 11 -H 3mg / m 2
_{C 8 F 17 SO 2 N (} C 3 H 7) - (CH 2 CH 2 O) 15 -H 2mg / m 2
_{C 8 F 17 SO 2 N (} C 3 H 7) - (CH 2 CH 2 O) 4 - (CH 2) 4 SO 3 Na
1mg / m ²
〔exposure〕
The obtained photosensitive material was exposed with a UV exposure machine or a laser exposure machine through a grid-like photomask (various distances / line widths between grids) or without a grid-like photomask. As for the photomask, exposure was also performed on the photomask with intentionally changed the standard deviation of the interstitial distance, and the following evaluation was performed.

[Chemical development]
The exposed photosensitive material was developed for 10 minutes at 20 ± 0.3 ° C. using the following developer, then fixed for 10 minutes at 20 ± 1.0 ° C. using the following fixer, and rinsed with pure water.

(Developer)
750 ml of water
Metol 2g
100 g of anhydrous sodium sulfite
Hydroquinone 5g
Borax 2g
Add water to make the total volume 1000ml (fixer)
600 ml of water
240g sodium thiosulfate
Sodium sulfite 15g
Acetic acid (28%) 48ml
Boric acid 7.5g
15g powdered alum
Add water to bring the total volume to 1000 ml and adjust to pH 4.3 using aqueous ammonia or glacial acetic acid.

[Physical development]
Next, the following physical developer was prepared and physically developed at 30 ± 0.3 ° C. for 10 minutes, followed by rinsing with pure water to obtain a sample of an electromagnetic wave shielding material having a conductive pattern.

(Physical developer)
900ml water
Citric acid 10g
Disodium hydrogen phosphate 25g
Ammonia water (28%) 3ml
Hydroquinone 2.3g
Silver nitrate 0.23g
Add water to bring the total volume to 1000 ml.

[Measurement and evaluation]
Measurement and evaluation were performed by the following methods.

(Line width)
The line width of the metal grid was measured with a microscope.

(Standard deviation of the distance between metal grids)
The distance between the metal lattices was measured with a microscope. As for the standard deviation of the distance between metal grids, the distance between metal grids was randomly measured at 100 points, and the standard deviation of the measured values was calculated.

(Aperture ratio)
The aperture ratio is a ratio of a portion having no fine line forming the metal lattice to the whole, and was calculated from the metal lattice line width and the interstitial distance.

(Shielding ability)
Samples were prepared at 15 cm × 15 cm, the shielding ability was measured by the KEC method, and evaluated according to the following criteria. As the numerical value of the shielding ability, a value of a frequency of 100 MHz is adopted.

◎: Shielding ability is 46 dB or more ◯: Shielding ability is 44 or more to less than 46 dB △: Shielding ability is 42 or more to less than 44 dB ×: Shielding ability is less than 42 dB (sharpness)
The sample was pasted on the plasma display panel screen from which the front filter was removed, the geometric pattern was displayed, and the sensory evaluation was performed on the sharpness of the boundary line. Evaluation was performed according to the following criteria.

◎: The boundary line is clearly visible. ○: The boundary line exists. ×: The boundary line is blurred. (Comprehensive evaluation)
The shielding ability and sharpness were comprehensively evaluated.

  The evaluation results are shown in Table 1.

  From Table 1, when the aperture ratio is 80 to 90%, the line width is 3 to 20 μm, and the standard deviation of the distance between metal lattices is in the range of 0.1 to 1.3, the shielding ability is high and the sharpness is high. It was found that a good sample was obtained. Furthermore, it was found that the sharpness is further improved when the line width is 14 μm or less.

Example 2
The amount of coating solution for the black and white developing emulsion prepared in Example 1 was adjusted, coating was performed so that the coating silver amount shown in Table 2 was achieved, and the resulting photosensitive material was subjected to UV exposure through a lattice photomask. After exposure with a machine, black-and-white development and intensification processing were performed in the same manner as in Example 1. At that time, the line width was adjusted to 12 μm, the aperture ratio to 90%, and the surface resistance to 10Ω / □. About the sample, the following intensification process time, comprehensive evaluation, and the same sharpness evaluation as Example 1 were performed. The evaluation results are shown in Table 2.

(Reinforcement processing time)
About the produced sample, it processed at 30 +/- 0.3 degreeC using the said physical development prescription, implemented the electrical conductivity evaluation by a time step, and evaluated it on the following reference | standard. The intensification time was the time required to reach 10Ω / □.

◎: Reinforcement time is less than 5 minutes ○: Reinforcement time is from 5 to less than 8 minutes △: Reinforcement time is from 8 to less than 15 minutes ×: Reinforcement time is 15 minutes or more (Comprehensive evaluation)
The intensification processing time and sharpness were comprehensively evaluated.

From Table 2, it was found that when the applied silver amount is 0.3 to 3.0 g / m ² , the intensifying treatment can be effectively achieved without sacrificing sharpness.

Example 3
Adjust the amount of gelatin monochrome developing emulsion prepared in Example 1, it was coated so that the amount of coated silver is 1.0 g / m ^2, the obtained photosensitive material, through a grid photomask After exposure with a UV exposure machine, black-and-white development and intensification processing were performed in the same manner as in Example 1. At that time, the line width was adjusted to 12 μm, the aperture ratio to 90%, and the surface resistance to 10Ω / □. About the sample, the following photosensitive layer film thickness, adhesiveness, color tone, and comprehensive evaluation were performed. Table 3 shows the evaluation results.

(Photosensitive layer thickness)
The film thickness of the photosensitive layer was measured by cutting a sample and enlarging a cross section with a microscope.

(Adhesiveness)
The produced sample was evaluated by a cross-cut cello tape (registered trademark) peel test (JIS K 5600-5-6) and evaluated according to the following criteria.

A: The remaining number of grids is 100/100
○: Remaining number of grids is 80 to 99/100
Δ: The remaining number of grids is 60 to 79/100
×: The remaining number of grids is 59 or less / 100
(Color tone)
About the produced sample, the fluorescent lamp of three wavelengths was copied, the change of the color of the fluorescent lamp was confirmed, and it evaluated according to the following reference | standard.

○: The fluorescent lamp looks white and is the same color as the direct-viewed fluorescent lamp. △: The fluorescent lamp looks white, but is slightly different from the direct-viewed fluorescent lamp.
The adhesiveness and color tone were comprehensively evaluated.

  From Table 3, it confirmed that the sample with favorable adhesiveness and a color tone was obtained as the film thickness of a photosensitive layer is 0.03-0.3 micrometer.

Example 4
The black-and-white developing emulsion prepared in Example 1 was adjusted to have a gelatin amount and coated so that the amount of coated silver was 1.0 g / m ² , and the resulting photosensitive material was passed through a lattice photomask. After exposure with a UV exposure machine, black-and-white development and intensification processing were performed in the same manner as in Example 1. At that time, the line width was adjusted to 12 μm, the aperture ratio to 90%, and the surface resistance to 10Ω / □. About the sample, the same intensification processing time as Example 2, and the following applicability | paintability and comprehensive evaluation were performed. Table 4 shows the evaluation results.

(Applicability)
The above emulsion was coated on a support, exposed on the front surface, and evaluation of coating unevenness after development was visually evaluated according to the following criteria.

○: No coating unevenness △: Coating unevenness is faint, but unevenness is not visible when viewed at a distance of 1 m or more x: Unevenness is visible even when viewed at a distance of 1 m or more (Comprehensive evaluation)
The intensification treatment time and applicability were comprehensively evaluated.

  From Table 4, it was found that by adjusting the volume ratio of silver halide / binder to 0.2 to 0.8, an efficient intensification treatment is possible and a coating property is also good.

Example 5
The black-and-white developing emulsion prepared in Example 1 was adjusted to have a gelatin amount and coated so that the amount of coated silver was 1.0 g / m ² , and the resulting photosensitive material was passed through a lattice photomask. After exposure with a UV exposure machine, black-and-white development and intensification processing were performed in the same manner as in Example 1. At that time, the time for the intensifying treatment was adjusted, and the aperture ratio was adjusted to 90% and the surface resistance to 10Ω / □ while changing the line height with a line width of 12 μm. About the sample, the following metal grid line height, cross-sectional area, moire, and comprehensive evaluation were performed. The evaluation results are shown in Table 5.

(Line height)
The line height of the metal grid line was measured by enlarging the cross section with a microscope.

(Cross sectional area)
The cross-sectional area of the metal grid was measured by cutting the metal grid and enlarging the cross section with a microscope.

(Moire)
About the produced sample, it affixed on the plasma display panel screen which removed the front filter, it was set as the white and black display screen, the moire was confirmed visually, and the following reference | standard evaluated.

○: Moire is not felt in both white and black △: Moire is felt only in one of white and black ×: Moire is felt in both white and black (Comprehensive evaluation)
The intensification treatment time and applicability were comprehensively evaluated.

  From Table 5, when the cross-sectional area S of the metal lattice satisfies the condition of 0.85 ≦ S / (W × H) ≦ 1.0 when the line width is W and the line height is H, it is possible to produce a high moire suitability. I understood.

Example 6
The black-and-white developing emulsion prepared in Example 1, was coated so that the amount of coated silver is 1.0 g / m ^2, the resulting light-sensitive material, the exposure to UV exposure machine via a lattice-like photomask After that, black-and-white development and intensification processing were performed in the same manner as in Example 1. A mask was prepared and used with a broken part. At that time, the line width was adjusted to 12 μm, the aperture ratio to 90%, and the surface resistance to 0.1Ω / □. With respect to the sample, the shielding ability was evaluated in the same manner as in Example 1 and the number of disconnected portions below. The evaluation results are shown in Table 6.

(Number of disconnections)
The number of disconnections was measured with a microscope for all 1 m ² metal lattice samples.

From Table 6, it was found that, in order to achieve the number of disconnected portions of 0 / m ² , the yield was very low, and good shielding ability could be maintained if the number was 100 / m ² or less.

Claims (11)

In an electromagnetic wave shielding film in which a silver halide photosensitive material having a photosensitive layer containing a silver halide and a binder on a support is subjected to pattern exposure, black-and-white development and intensification processing are performed, and metal is arranged in a lattice shape An electromagnetic wave shielding film, wherein the line width of the metal grid is 3 to 20 μm, the aperture ratio is 80 to 95%, and the standard deviation of the distance between the metal grids is 0.1 to 1.3. The electromagnetic wave shielding film according to claim 1, wherein a line width of the metal lattice is 3 to 14 μm. 3. The electromagnetic wave shielding film according to claim 1, wherein the silver halide photosensitive material has a silver halide coating amount of 0.3 to 3.0 g / m ² in terms of metallic silver. The film thickness of the said photosensitive layer is 0.03-0.3 micrometer, The electromagnetic wave shielding film of any one of Claims 1-3 characterized by the above-mentioned. The electromagnetic wave shielding film according to any one of claims 1 to 4, wherein the photosensitive layer has a silver halide / binder volume ratio of 0.2 to 0.8. 6. The cross-sectional area S of the metal lattice satisfies a relationship of 0.85 ≦ S / (W × H) ≦ 1.0 with respect to the line width W and the line height H. The electromagnetic wave shielding film of any one of these. Electromagnetic wave shielding film according to claim 1, wherein the number of disconnected parts of the metal grid surface direction 1 m ² per electromagnetic wave shielding film is 1 to 100. The electromagnetic wave shielding film according to claim 1, wherein the intensification process is physical development. The electromagnetic wave shielding film according to any one of claims 1 to 7, wherein the intensifying treatment is performed after physical development. The electromagnetic wave shielding film according to claim 8 or 9, wherein a physical developer used for the physical development is acidic. A plasma display panel comprising the electromagnetic wave shielding film according to claim 1.