JP2007067269A - Electromagnetic wave shielding material roll body for display, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic wave shielding material roll body for a display which has less partial variations in the performance of an electromagnetic wave shield and has stable performance in photographic silver-plating method, and to provide a manufacturing method thereof. <P>SOLUTION: The electromagnetic wave shielding material roll body for a display is provided the a metal mesh pattern 22 of screen size of a display, on at least one surface of a long transparent base material 21 with a predetermined interval 24 in the longitudinal direction of the transparent base material 21, and is fed in a rolled state. The metal mesh pattern 22 has a developing silver mesh pattern, generated by a photographic process and a plating layer electrolytically plated at least thereon, a shielding frame 23 made of a metal mesh or a metal thin film is arranged around the metal mesh pattern 22, and a feed layer 25 for electrolytic plating having a predetermined width which contacts both the external sides of the width direction of the shielding frame 23 is provided contiguously in the longitudinal direction of the transparent base material 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electromagnetic shielding material used for various displays such as CRT and PDP (plasma display) and a manufacturing method thereof, and more particularly, to an electromagnetic shielding material roll body supplied in a roll state and a manufacturing method thereof.

  In recent years, in various displays such as CRT and PDP (plasma display), electromagnetic waves generated from the front of the display adversely affect the human body and malfunction of surrounding electronic devices has become a problem. Along with the clearness of the display, countermeasures against the influence of the display on the surroundings are becoming increasingly important.

  Conventionally, various transparent conductive films and electromagnetic wave shielding films have been developed in response to the requirement that electromagnetic waves generated from a display leak outside and prevent adverse effects on the human body. Known electromagnetic shielding materials are roughly classified into two types: an electromagnetic shielding material made of a transparent conductive film and an electromagnetic shielding material made of a conductive metal mesh. Among these, the electromagnetic shielding material using a transparent conductive film is superior in transparency to the electromagnetic shielding material using a metal mesh, but has a large surface resistivity and inferior electromagnetic shielding performance. For this reason, in the use which shields the electromagnetic waves from the apparatus which generate | occur | produces strong electromagnetic waves, such as PDP, the electromagnetic wave shielding material by a metal mesh is preferable.

Furthermore, as a method for producing an electromagnetic wave shielding material using a conductive metal mesh, the following methods (1) to (3) are exemplified.
(1) An etching method in which a metal foil is bonded to a transparent substrate, or a metal thin film is deposited on the transparent substrate, and then a conductive metal pattern is formed by a photolithographic method (see, for example, Patent Document 1).
(2) A printing-plating method in which a conductive metal paste is printed on a transparent substrate and then plated to form a conductive metal pattern (see, for example, Patent Document 2).
(3) A photographic silver-plating method for forming a conductive metal pattern by forming a fine line pattern with metallic silver developed by a photographic method and then physically developing and / or plating the metallic silver (for example, Patent Document 3) And Patent Document 4).

  Then, there are two methods shown in the following (a) and (b) for forming a mesh pattern with metallic silver by a photographic manufacturing method.

(A) A silver salt-containing layer containing a silver salt provided on a support is exposed and developed to form a metallic silver part and a light-transmitting part, and the metallic silver part is further subjected to physical development and A method of forming a conductive metal part in which conductive metal particles are supported on the metal silver part by plating (see, for example, Patent Document 3). In this method, phenomenon silver does not appear in the portion that is covered with the exposure mask and is not exposed, and developed silver appears in the portion that is not covered with the exposure mask and exposed. Therefore, compared with the exposure mask. This is a negative exposure / development method in which developed silver appears in an inverted form.

(B) A light-sensitive material having a physical development nucleus layer and a silver halide emulsion layer in this order is exposed on a transparent substrate, and metallic silver is deposited on the physical development nucleus in an arbitrary fine line pattern. A method of plating a metal using the physically developed metallic silver as a catalyst nucleus after removing a layer provided on the development nucleus (see, for example, Patent Document 4). In this method, phenomenon silver appears in a portion that is covered with an exposure mask and is not exposed, and developed silver does not appear in a portion that is not covered with the exposure mask and is exposed. Is a positive exposure / development method (silver complex diffusion transfer method, hereinafter referred to as DTR method).
Japanese Patent Laid-Open No. 10-075087 JP 11-170420 A JP 2004-221564 A WO2004 / 007810

In the etching method (1), it is a problem from the viewpoint of saving resources that only a very small portion which becomes a thin line portion is left by etching and most other metals are dissolved and removed. In addition, since the maximum standard dimension width of a commercially available metal foil is about 600 mm or less, an electromagnetic wave shielding material having a wider dimension width cannot be produced by the method of bonding the metal foil. In addition, when a metal thin film is deposited, there is a problem that it cannot be easily manufactured because a huge equipment cost is required.
In the printing-plating method (2), it is difficult to reduce the line width of the mesh pattern to 30 μm or less, and there is a problem in that the adhesiveness between the transparent substrate and the mesh pattern is poor and is easily peeled off.

In the photographic silver-plating method of (3) above, high electromagnetic shielding properties are obtained, and there is no restriction on the dimensions of the transparent base material, so that it can be produced with a roll-to-roll and the productivity is very high. This is a preferred production method.
By the way, in the photographic silver-plating method, a fine line pattern is formed by electroless plating and / or electrolytic plating on the metal silver having a mesh pattern developed by any of the photographic methods (a) and (b). In such a case, the electroless plating has a problem that the plating speed is slow, the quality control of the electroless plating solution is difficult, and the manufacturing cost is high.
In the case of electrolytic plating, the plating speed is faster than that of electroless plating. However, in the prior art, electrolytic plating is intermittently performed for each mesh pattern by transferring to the electrolytic cell by step feed for electrolytic plating. There is a problem that productivity is low because it is performed by feeding.
In addition, when performing electroplating in a continuous process, it is technically difficult to uniformly and stably supply power to supply electrolysis current, resulting in uneven plating thickness in part of the mesh pattern. As a result, there is a problem that a part of the mesh pattern has a partial variation in electromagnetic shielding performance.

  The present invention has been made in view of the above circumstances. In the photographic silver-plating method, the electromagnetic wave shield for a display supplied in a roll state with little partial variation in the performance of the electromagnetic wave shield and stable performance is provided. It is an object to provide a material and a manufacturing method thereof.

In order to solve the above problems, the present invention is provided on at least one surface of a long transparent substrate, a metal mesh pattern of the screen size of the display is provided at a certain interval in the longitudinal direction of the transparent substrate, And the electromagnetic wave shielding material roll for display supplied in the state of a roll, wherein the metal mesh pattern has a developed silver mesh pattern generated by a photographic method and a plating layer at least electrolytically plated thereon, A shield frame made of a metal mesh or a metal thin film is disposed around the metal mesh pattern, and a constant width electroplating feeding layer in contact with both outer sides in the width direction of the shield frame is continuous in the longitudinal direction of the transparent substrate. An electromagnetic wave shielding material roll for display is provided.
The electrolytic plating power supply layer is preferably made of a metal mesh or a metal thin film and has a width of 15 to 80 mm.

It is preferable that the transparent base is further made of a metal mesh or a metal thin film, and a connecting band for connecting adjacent shield frames is disposed on one side or both sides in the longitudinal direction of the shield frame.
As the developed silver mesh pattern, either a negative-type development method in which developed silver appears in the exposed portion or a positive-type development method in which developed silver appears in the unexposed portion is adopted. It is also possible to do.

  In the present invention, a metal mesh pattern having a screen size of a display is provided on at least one surface of a long transparent substrate at a predetermined interval in the longitudinal direction of the transparent substrate, and is supplied in a roll state. A developed silver mesh pattern generated by a photographic method, a shield frame made of a metal mesh or a metal thin film disposed around the developed silver mesh pattern, A transparent base material provided on at least one surface with a power supply layer for electrolytic plating having a constant width that is in contact with both outer sides in the width direction of the shield frame and continuously provided in the longitudinal direction of the transparent base material. After continuous feeding, a plating layer is formed on the developed silver mesh pattern by a process including at least electrolytic plating through the electrolytic plating power supply layer. Form, to provide a method of manufacturing a display for the electromagnetic wave shielding material roll body, characterized in that the roll body wound again.

It is preferable that the transparent base material of the raw fabric roll is further made of a metal mesh or a metal thin film, and a connection band for connecting adjacent shield frames is disposed on one side or both sides in the longitudinal direction of the shield frame.
As the developed silver mesh pattern of the transparent base material of the raw fabric roll, a positive development method in which developed silver is developed in an unexposed portion, which is generated by a negative developing method in which developed silver is developed in an exposed portion. It is possible to employ any of those generated by the above.

According to the present invention, in the photographic silver-plating method, it is possible to produce an electromagnetic wave shielding material roll for display having a stable performance with little variation in the performance of the electromagnetic wave shielding. Since the electromagnetic shielding material can be continuously produced and supplied by roll-to-roll, the production cost can be significantly reduced.
When a connecting band for connecting adjacent shield frames is provided on one side or both sides in the longitudinal direction of the shield frame and connecting adjacent shield frames, power supply for supplying an electrolytic current can be performed uniformly and stably. Therefore, the “plating unevenness” of the plating layer and the partial variation in the electromagnetic wave shielding performance of the mesh pattern caused by the plating layer can be suppressed.

The present invention will be described below with reference to the drawings based on the best mode.
FIG. 1 is a schematic view showing an example of an apparatus for performing electroplating by roll-to-roll in the present invention. FIG. 2 is a partial plan view showing an example of the arrangement of the mesh pattern and the power feeding layer in the electromagnetic wave shielding material roll for display according to the present invention. FIG. 3 is a partial plan view showing an example of the arrangement of the mesh pattern, the power feeding layer, and the connecting band in the electromagnetic wave shielding material roll for display according to the present invention. FIG. 4 is a partial plan view showing another example of the arrangement of the mesh pattern, the power feeding layer, and the connection band in the electromagnetic wave shielding material roll for display according to the present invention. FIG. 5 is a partial plan view showing an example of the arrangement of mesh patterns and power feeding layers in a conventional electromagnetic wave shielding material for a display.

(Production method of electrolytic plating layer by continuous power supply)
In the electromagnetic shielding material manufacturing apparatus 1 shown in FIG. 1, a roll sheet 3 on which at least one surface of a long transparent substrate is exposed and developed by a photographic method and developed silver is fixed in a mesh pattern shape is a roll. From the original roll 2 wound up in a shape, it is transferred from left to right in the figure by transfer rolls 4, 4, 4,. First, the roll sheet 3 is passed through the water washing tank 5 and washed to remove unnecessary foreign matters and contaminants. If necessary, it is passed through an electroless plating tank (not shown) and electrolessly plated on the developed silver mesh pattern, and then transferred to at least the electrolytic plating tank 6.

  In the electrolytic plating tank 6, electrolytic plating is performed through the electrolytic plating solution 9 between the feeding rolls 7, 7 serving as the cathode and the positive electrode plates 8, 8 serving as the anode, and the developed silver mesh pattern of the roll sheet 3 and / or An electrolytic plating layer is deposited on the electroless plating layer formed thereon. The temperature of the electrolytic plating solution 9 is controlled by a temperature regulator (not shown) so as to be a predetermined temperature. The power supply rolls 7 and 7 are provided at the entrance for the roll sheet 3 to enter and exit the electrolytic plating tank 6, and the electrolytic plating solution 9 leaks from the gap between the power supply rolls 7 and 7 of the electrolytic plating tank 6. Can fall. Therefore, a receiving tank 10 that receives the leaked electrolytic plating solution 9 is installed below the electrolytic plating tank 6, and the electrolytic plating solution 9 received in the receiving tank 10 passes through the circulation pump 11 and the filter 12 again. It is configured to recirculate to the electrolytic plating tank 6.

  The roll sheet 3 exiting the electrolytic plating tank 6 is washed away with unnecessary electrolytic plating solution 9 in the water washing tank 13, drained and dried by a dryer 14, and wound up again to be rolled up to form a roll-shaped electromagnetic shielding material roll 15. It becomes.

  Here, in the present invention, in the case of electrolytic plating in the electrolytic plating tank 6, there is a case where a feeding layer for electrolytic plating (hereinafter referred to as “continuous feeding layer”) provided continuously in the longitudinal direction on the roll sheet 3. ) To supply power to the developed silver mesh pattern.

  In the prior art, like a roll sheet 50 shown in FIG. 5, mesh patterns 52, 52,... Of the screen size of the display at a constant interval 54 on a long transparent substrate 51 and around the mesh pattern 52. The shield frames 53, 53,... Are arranged, and the power supply layers 55, 55 are provided on both outer sides in the width direction of the respective shield frames 53. In the prior art, the roll sheet 3 is transferred stepwise by the transfer rolls 4, 4, 4,..., The roll sheet 3 is intermittently introduced into the electrolytic plating tank 6, and one screen is displayed in the electrolytic plating tank 6. This is an intermittent method in which electrolytic plating is performed for each mesh pattern 52 corresponding to the size. For this reason, in the prior art, the supply and transfer of the roll sheet 3 are stopped for a certain period of time during each plating step in which each mesh pattern 52 is electroplated, so that productivity is limited to a low level. It was.

  Therefore, in the present invention, the exposed and developed roll sheet 3 is continuously fed out from the raw fabric roll 2 and transferred to the electroplating tank 6 by continuous feeding of the transfer rolls 4, 4,... In order to perform the plating, like the roll sheet 20 shown in FIG. 2, mesh patterns 22, 22,..., And mesh patterns 22 having a screen size of the display at regular intervals 24 on at least one surface of the long transparent substrate 21. Are arranged in such a manner that continuous feed layers 25, 25 having a constant width continuous in the longitudinal direction of the transparent base material 21 are provided in contact with both outer sides in the width direction of the shield frame 23. Is used.

  The continuous power supply layer 25 is in contact with the power supply rolls 7 and 7 that serve as a cathode before and after the portion where the roll sheet 3 is introduced into the electrolytic plating tank 6. As a result, at the time of electrolytic plating, an electrolytic current is supplied to the mesh pattern 22 through the continuous power supply layer 25, and plating by electrolytic plating is performed on the developed silver mesh pattern and / or the electroless plating layer formed thereon. A layer is formed.

  Further, in another embodiment of the present invention, like a roll sheet 30 shown in FIG. 3, mesh patterns 32, 32 having a display screen size at a constant interval 34 on at least one surface of a long transparent substrate 31, ... and shield frames 33, 33,... Around the mesh pattern 32 are arranged, and the continuous feed layers 35, 35 having a constant width continuous in the longitudinal direction of the transparent substrate 31 are in contact with both outer sides in the width direction of the shield frame 33. The connecting band 36, 36 that connects the adjacent shield frames 33, 33 is provided on one side of the shield frame 33 in the longitudinal direction.

  In still another embodiment of the present invention, like a roll sheet 40 shown in FIG. 4, mesh patterns 42, 42,... Of the screen size of the display at a constant interval 44 on at least one surface of a long transparent substrate 41. Are arranged around the mesh pattern 42, and the continuous feeding layers 45, 45 having a constant width continuous in the longitudinal direction of the transparent base material 41 are in contact with both outer sides in the width direction of the shield frame 43. Provided is one in which connecting bands 46, 46 for connecting adjacent shield frames 43, 43 are arranged on both sides in the longitudinal direction of the shield frame 43.

As in the roll sheet 30 shown in FIG. 3 and the roll sheet 40 shown in FIG. 4, the adjacent shield frames 33 and 43 are connected by connecting bands 36 and 46 made of mesh or metal thin film to supply an electrolytic current. Power feeding can be performed uniformly and stably, and “plating unevenness” in which a variation in plating thickness occurs in part of the mesh patterns 32 and 42 can be reduced. Furthermore, as a result, it is possible to suppress the occurrence of partial variations in electromagnetic shielding performance in a part of the mesh patterns 32 and 42.
In addition, as shown in FIG.3 and FIG.4, as shown in FIG.3 and FIG.4, the connection bands 36 and 46 may be branched into two or more, depending on the necessity of appropriately dispersing the electrolytic current, One wide one may be provided. Further, the connection bands 36 and 46 may be made of a metal mesh having a selected line width and interval, or may be made of a metal thin film, as long as it is suitable for dispersing the electrolysis current. I do not care.

  The mesh patterns 22, 32, and 42, which are the screen size of the display, are developed silver mesh patterns generated by the photographic manufacturing method in the raw roll 2. That is, the raw fabric roll 2 includes a developed silver mesh pattern, shield frames 23, 33, 43 made of a metal mesh or a metal thin film, and a transparent base on at least one surface of the long transparent base materials 21, 31, 41. A continuous feed layer 25, 35, 45 having a constant width provided continuously in the longitudinal direction of the materials 21, 31, 41, and connection bands 36, 46 provided arbitrarily are formed. Further, the mesh patterns 22, 32, and 42 in the electromagnetic wave shielding material roll body 15 are obtained by forming a plating layer on the original developed silver mesh pattern at least by electrolytic plating. The continuous power supply layers 25, 35, and 45 are made of a metal mesh or a metal thin film, and preferably have a width of 15 to 80 mm.

(Transparent substrate)
As the transparent base materials 21, 31, and 41 used in the present invention, those having transparency in the visible region and generally having a total light transmittance of 90% or more are preferable. Especially, the resin film which has flexibility is used suitably at the point which is easy to handle. Specific examples of the transparent resin film used for the transparent substrates 21, 31, 41 include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), acrylic resins, epoxy resins, fluororesins, silicone resins, Single layer of 50 to 300 μm thickness made of polycarbonate resin, diacetate resin, triacetate resin, polyarylate resin, polyvinyl chloride, polysulfone resin, polyether sulfone resin, polyimide resin, polyamide resin, polyolefin resin, cyclic polyolefin resin, etc. A multi-layer composite film made of a film or the transparent resin is mentioned.

(Metal mesh pattern production method)
The method for producing a conductive metal mesh applicable to the present invention is to form a conductive metal pattern by forming a fine line pattern with metallic silver developed by a photographic method and then physically developing and / or plating the metallic silver. This is due to the exposure development method.
In the exposure development method based on this photographic method applicable to the present invention, as described above, (a) developed silver appears in an exposed portion that is not covered with the exposure mask, that is, opposite to the exposure mask. A so-called negative-type exposure development method in which developed silver appears in the form, and (b) so-called developed silver appears in the same form as the exposure mask, that is, the phenomenon silver appears in the portion that is covered with the exposure mask and not exposed. There are two types of positive exposure development methods. Either (a) a negative exposure / development method or (b) a positive exposure / development method can be applied to the present invention.

  Hereinafter, a method for producing a metal mesh pattern using a positive exposure / development method (DTR method) and an electrolytic plating method will be described. In the case of the DTR method, it is preferable that a physical development nucleus layer is provided in advance on the transparent substrate surface. As the physical development nuclei, fine particles (having a particle size of about 1 to several tens of nm) made of heavy metals or sulfides thereof are used. Examples thereof include colloids such as gold and silver, metal sulfides obtained by mixing water-soluble salts such as palladium and zinc and sulfides, and the like. The fine particle layer of these physical development nuclei can be provided on the transparent substrate by a vacuum deposition method, a cathode sputtering method, a coating method or the like. From the viewpoint of production efficiency, a coating method is preferably used. The content of physical development nuclei in the physical development nuclei layer is suitably about 0.1 to 10 mg per square meter in solid content.

  The transparent substrate can be provided with an adhesive layer of a polymer latex layer such as vinylidene chloride or polyurethane, and an intermediate layer made of a hydrophilic binder such as gelatin can be provided between the adhesive layer and the physical development nucleus layer. it can.

  The physical development nucleus layer preferably contains a hydrophilic binder. The amount of the hydrophilic binder is preferably about 10 to 300% by mass with respect to the physical development nucleus. As the hydrophilic binder, gelatin, gum arabic, cellulose, albumin, casein, sodium alginate, various starches, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, a copolymer of acrylamide and vinyl imidazole, and the like can be used. The physical development nucleus layer may also contain a hydrophilic binder crosslinking agent.

  The physical development nucleus layer and the intermediate layer can be applied by an application method such as dip coating, slide coating, curtain coating, bar coating, air knife coating, roll coating, gravure coating, spray coating, and the like. In the present invention, the physical development nucleus layer is preferably provided as a continuous and uniform layer by the above-described coating method.

  The supply of silver halide for depositing metallic silver on the physical development nucleus layer is performed by a method in which the physical development nucleus layer and the silver halide emulsion layer are integrally formed in this order on a transparent substrate, or another paper or plastic resin. There is a method of supplying a soluble silver complex salt from a silver halide emulsion layer provided on a substrate such as a film. From the viewpoint of cost and production efficiency, the former physical development nucleus layer and the silver halide emulsion layer are preferably provided integrally.

The silver halide emulsion can be produced according to a general method for producing a silver halide emulsion of a silver halide photographic light-sensitive material. The silver halide emulsion is usually prepared by mixing and ripening an aqueous silver nitrate solution, an aqueous halogen solution of sodium chloride or sodium bromide in the presence of gelatin.
The silver halide composition of the silver halide emulsion layer preferably contains 80 mol% or more of silver chloride, and more preferably 90 mol% or more is silver chloride. The conductivity of the physically developed silver formed by increasing the silver chloride content is improved.

  The silver halide emulsion layer is sensitive to various light sources. As one method for producing an electromagnetic wave shielding material, for example, formation of physically developed silver having a fine line pattern such as a mesh shape can be mentioned. In this case, the silver halide emulsion layer is exposed in a fine line pattern. As an exposure method, a method of exposing a fine line pattern transmission original and a silver halide emulsion layer in close contact with each other, or scanning exposure using various laser beams. There are ways to do this. The former contact exposure is possible even if the silver halide has relatively low photosensitivity, but in the case of scanning exposure using laser light, relatively high photosensitivity is required. Therefore, when the latter exposure method is used, the silver halide may be subjected to chemical sensitization or spectral sensitization with a sensitizing dye in order to increase the sensitivity of the silver halide. Chemical sensitization includes metal sensitization using a gold compound or silver compound, sulfur sensitization using a sulfur compound, or a combination thereof. Gold-sulfur sensitization using a gold compound and a sulfur compound in combination is preferable. In the exposure method using the laser beam described above, a laser beam having an oscillation wavelength of 450 nm or less, for example, a blue semiconductor laser (also referred to as a violet laser diode) having an oscillation wavelength of 400 to 430 nm is used. It can be handled even under a yellow fluorescent lamp.

  Halation at any position on the transparent substrate on which the physical development nucleus layer is provided, for example, an adhesive layer, an intermediate layer, a physical development nucleus layer or a silver halide emulsion layer, a protective layer, or a backing layer provided with a support interposed therebetween Or a dye or pigment for preventing irradiation may be contained.

  When producing an electromagnetic shielding material using a photosensitive material in which a silver halide emulsion layer is coated directly on the physical development nucleus layer or via an intermediate layer, an arbitrary fine line pattern such as a mesh pattern is used. After exposing a transparent original and the photosensitive material in close contact, or by scanning and exposing a digital image of an arbitrary fine line pattern to the photosensitive material with various laser light output machines, in the presence of a soluble silver complex salt forming agent and a reducing agent. Silver complex diffusion transfer development (DTR development) occurs by processing in an alkaline solution, the silver halide in the unexposed area is dissolved to form a silver complex salt, which is reduced on the physical development nuclei, and metallic silver is precipitated to form a fine line. A physically developed silver thin film with a pattern can be obtained. The exposed portion is chemically developed in the silver halide emulsion layer to become blackened silver. After development, the silver halide emulsion layer and the intermediate layer, or the protective layer provided as necessary, are washed away with water, and a physically developed silver thin film having a fine line pattern is exposed on the surface.

  After DTR development, the silver halide emulsion layer or the like provided on the physical development nucleus layer may be removed by washing with water or transferring and peeling to a release paper or the like. There are two methods for removing the water washing: a method of removing hot water using a scrubbing roller or the like while jetting it with a nozzle or the like, and a method of removing hot water by jetting with a nozzle or the like.

  On the other hand, when the soluble silver complex salt is supplied from a silver halide emulsion layer provided on a substrate different from the transparent substrate on which the physical development nucleus layer is coated, the silver halide emulsion layer is exposed as described above. After that, a transparent substrate coated with a physical development nucleus layer and another photosensitive material coated with a silver halide emulsion layer are superposed in an alkaline solution in the presence of a soluble silver complexing agent and a reducing agent. After several tens of seconds to several minutes after taking out from the alkaline solution, the both are removed to obtain a physically developed silver thin film having a fine line pattern deposited on the physical development nuclei.

  Next, a soluble silver complex salt forming agent, a reducing agent, and an alkali solution necessary for silver complex diffusion transfer development will be described. The soluble silver complex salt forming agent is a compound that dissolves silver halide to form a soluble silver complex salt, and the reducing agent is a compound that reduces this soluble silver complex salt to precipitate metallic silver on physical development nuclei. These actions are performed in an alkaline solution.

  Examples of the soluble silver complex forming agent used in the present invention include sodium thiosulfate, thiosulfate such as ammonium thiosulfate, thiocyanate such as sodium thiocyanate and ammonium thiocyanate, alkanolamine, sodium sulfite, and potassium bisulfite. Sulfites such as T. H. Examples include the compounds described in 474-475 (1977) of James The Theory of the Photographic Process 4th edition.

  As the reducing agent, a developing agent known in the field of photographic development can be used. For example, hydroquinone, catechol, pyrogallol, methylhydroquinone, chlorohydroquinone and other polyhydroxybenzenes, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1-phenyl-3-pyrazolidone, 1-phenyl-4-methyl- Examples include 3-pyrazolidones such as 4-hydroxymethyl-3-pyrazolidone, paramethylaminophenol, paraaminophenol, parahydroxyphenylglycine, paraphenylenediamine, and the like.

  The above-mentioned soluble silver complex salt forming agent and reducing agent may be applied to the transparent substrate together with the physical development nucleus layer, added to the silver halide emulsion layer, or contained in the alkaline solution. It may be allowed to be contained, and may be further contained in a plurality of positions, but is preferably contained at least in the alkaline liquid.

  The content of the soluble silver complex salt forming agent in the alkaline solution is suitably used in the range of 0.1 to 5 mol per liter of the developer, and the reducing agent is 0.05 to 1 per liter of the developer. It is suitable to use in the molar range.

  The pH of the alkaline solution is preferably 10 or more, and more preferably in the range of 11-14. Application of the alkaline solution for silver complex diffusion transfer development may be an immersion method or a coating method. The immersion method is, for example, transporting while immersing a transparent substrate provided with a physical development nucleus layer and a silver halide emulsion layer in an alkaline solution stored in a large amount in a tank. For example, about 40 to 120 ml of an alkaline solution per square meter is applied on the silver halide emulsion layer.

As described above, there are fine line patterns in which, for example, fine lines having a line width of about 10 to 100 μm are provided in a grid pattern in the vertical and horizontal directions. If the narrow line width is reduced and the interval between the gratings is increased, the translucency increases. However, the conductivity decreases, and conversely, if the fine line width is increased to reduce the lattice spacing, the translucency is decreased and the conductivity is increased. The silver image formed by physical development of an arbitrary fine line pattern formed on the transparent substrate according to the present invention has a translucency with a total light transmittance of 50% or more and a conductivity with a surface resistivity of 10 ohms / □ or less simultaneously. It is difficult to satisfy. Specifically, the silver image by this physical development has a conductivity of a surface resistivity of 50 ohms / square or less, preferably 20 ohms / square or less, but a pattern with a fine line width of 50 μm or less, for example, a fine line width of 20 μm. When the total light transmittance is 50% or more, the surface resistivity becomes several hundred ohms / square to 1000 ohms / square or more. However, the silver image by the physical development itself forms a silver image because the metallic silver particles forming the silver image obtained after the development processing are extremely small and the amount of the hydrophilic binder present in the silver image is extremely small. Since the silver image is formed in a state close to the close-packed state and the electroconductive property is obtained, the fine silver wire pattern can be obtained by plating with a metal such as copper or nickel, especially by electroplating. Is a transparent thin line pattern having a total light transmittance of 50% or more, preferably 60% or more, when the thickness is 0.5 to 15 μm and the line width is 10 to 50 μm. The conductivity of □ or less, preferably 7 ohm / □ or less can be maintained.
In order to improve the total light transmittance of the metal mesh, it is necessary to sufficiently increase the area of the light transmission portion between the fine lines with respect to the area of the region where the fine lines are provided. For this reason, it is preferable that the space | interval of a thin wire | line is 100-900 micrometers, More preferably, it is 150-700 micrometers.

  The thickness of the metal-plated fine line pattern can be arbitrarily changed according to desired characteristics, but is in the range of 0.5 to 15 μm, preferably 2 to 12 μm. Moreover, the electromagnetic shielding material produced by the above-mentioned method can obtain a shielding effect of 30 dB or more over a wide frequency band such as 30 MHz to 1,000 MHz.

  The thin line pattern of physically developed silver can be plated by either electroless plating, electrolytic plating, or a combination of the two. However, when preparing an electromagnetic shielding layer on a transparent substrate, From the viewpoint that a roll-like long web provided with a physical development nucleus layer and a silver halide emulsion layer can be subjected to at least a series of treatments such as exposure of a fine line pattern, development treatment and plating treatment. Is preferred.

  In the present invention, the metal plating method can be performed by a known method. For example, the electrolytic plating method is a conventionally known method such as copper, nickel, silver, gold, solder, or a multilayer or composite system of copper / nickel. For these, reference can be made to documents such as “Surface Treatment Technology Overview; Technical Data Center, Inc., December 21, 1987, first edition, pages 281 to 422”.

It is preferable to use copper and / or nickel for reasons such as easy plating, excellent electrical conductivity, plating on a thick film, and low cost. As an example of electrolytic plating, the transparent base material on which the above-described physically developed silver is formed is immersed in a bath mainly composed of copper sulfate, sulfuric acid and the like, and a current density of 1 to 20 amperes / percent at 10 to 40 ° C. Plating can be performed by energizing at dm ² .
The type of the electrolytic plating tank 6 to be used may be either a vertical type or a horizontal type, but the length of the electrolytic plating tank is set according to the transfer speed of the roll sheet 3 so as to ensure a predetermined plating residence time. decide.

  The electromagnetic wave shielding layer (metal mesh pattern) obtained by the above method has a total light transmittance of 50% or more and a surface resistivity of 10 when the mesh pattern has a thickness of 0.5 to 15 μm and a line width of 10 to 50 μm. It has excellent translucency and electrical conductivity of ohm / square or less, and can exhibit a shielding effect of 30 dB or more over a wide frequency band such as 30 MHz to 1,000 MHz.

  ADVANTAGE OF THE INVENTION According to this invention, the electromagnetic wave shielding material roll body for a display with few partial dispersion | variation of the performance of electromagnetic wave shielding and the stable performance can be provided, This electromagnetic wave shielding material roll body is an optical filter for PDP, etc. Since it can be supplied in the state of a roll to the manufacturing process, it is greatly beneficial for quality improvement and cost reduction.

In this invention, it is the schematic which shows an example of the apparatus which performs electroplating with a roll to roll. It is a fragmentary top view which shows an example of arrangement | positioning of the mesh pattern in the electromagnetic wave shielding material roll body for displays of this invention, and a continuous electric power feeding layer. It is a fragmentary top view which shows an example of arrangement | positioning of the mesh pattern in the electromagnetic wave shielding material roll body for displays of this invention, a continuous electric power feeding layer, and a connection band. It is a fragmentary top view which shows the other example of arrangement | positioning of the mesh pattern in the electromagnetic wave shielding material roll body for displays of this invention, a continuous electric power feeding layer, and a connection band. It is a fragmentary top view which shows an example of arrangement | positioning of the mesh pattern and electric power feeding layer in the conventional electromagnetic wave shielding material for displays.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electromagnetic-shielding material manufacturing apparatus, 2 ... Raw material roll, 3 ... Roll sheet, 4 ... Transfer roll, 5 ... Water washing tank, 6 ... Electrolytic plating tank, 7 ... Feeding roll, 8 ... Positive electrode plate, 9 ... Electrolysis Plating solution, 10 ... receiving tank, 11 ... circulating pump, 12 ... filter, 13 ... water washing tank, 14 ... dryer, 15 ... electromagnetic wave shielding material roll body, 20, 30, 40 ... roll sheet according to the present invention, 21, 31, 41 ... Transparent substrate, 22, 32, 42 ... Mesh pattern, 23, 33, 43 ... Shield frame, 24, 34, 44 ... Spacing, 25, 35, 45 ... Continuous feeding layer, 36, 46 ... Connection band .

Claims (9)

An electromagnetic wave for display, which is provided in a roll state in which a metal mesh pattern having a screen size of a display is provided on at least one surface of a long transparent substrate at a predetermined interval in the longitudinal direction of the transparent substrate. A shield material roll,
The metal mesh pattern has a developed silver mesh pattern generated by a photographic process and a plating layer at least electroplated thereon, and a shield frame made of a metal mesh or a metal thin film is arranged around the metal mesh pattern. An electromagnetic wave shielding material roll for a display, comprising: a feed layer for electrolytic plating having a constant width which is provided and is in contact with both outer sides in the width direction of the shield frame.   2. The electromagnetic wave shielding material roll for display according to claim 1, wherein the power feeding layer for electrolytic plating is made of a metal mesh or a metal thin film and has a width of 15 to 80 mm.   2. The transparent base material further comprising a metal mesh or a metal thin film, and connecting bands for connecting adjacent shield frames are arranged on one side or both sides in the longitudinal direction of the shield frame. Or the electromagnetic wave shielding material roll for displays according to 2.   4. The electromagnetic wave shielding material roll for display according to claim 1, wherein the developed silver mesh pattern is generated by a negative type developing method in which developed silver is developed in an exposed portion. 5. body.   4. The electromagnetic wave shielding material roll for display according to claim 1, wherein the developed silver mesh pattern is generated by a positive developing method in which developed silver appears in a portion not exposed to light. 5. body. An electromagnetic wave shield for a display in which a metal mesh pattern having a screen size of a display is provided on at least one surface of a long transparent substrate at a predetermined interval in the longitudinal direction of the transparent substrate, and is supplied in a roll state A method of manufacturing a material roll body,
A developed silver mesh pattern generated by a photographic manufacturing method, a shield frame made of a metal mesh or a metal thin film disposed around the developed silver mesh pattern, the transparent base material in contact with both outer sides in the width direction of the shield frame After continuously feeding a transparent base material provided on at least one surface with a constant width electroplating power supply layer continuously provided in the longitudinal direction from the raw roll, the electroplating power supply layer was passed through. A method for producing an electromagnetic wave shielding material roll for display, wherein a plating layer is formed on the developed silver mesh pattern by a process including at least electrolytic plating, and is wound again to form a roll.   The transparent roll base material further comprises a metal mesh or a metal thin film, and a connection band for connecting adjacent shield frames is disposed on one side or both sides in the longitudinal direction of the shield frame. The manufacturing method of the electromagnetic wave shielding material roll body for displays of Claim 6 which does.   The display according to claim 6 or 7, wherein the developed silver mesh pattern of the transparent base material of the raw fabric roll is generated by a negative developing method in which developed silver is developed in an exposed portion. Of manufacturing electromagnetic wave shielding material roll body for use.   The display according to claim 6 or 7, wherein the developed silver mesh pattern of the transparent base material of the raw fabric roll is generated by a positive development method in which developed silver is developed in a portion not exposed to light. Of manufacturing electromagnetic wave shielding material roll body for use.

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