JP4799971B2 - Electromagnetic wave shielding material roll body and manufacturing method thereof - Google Patents

Description

  The present invention relates to an electromagnetic shielding material and a manufacturing method thereof, and more particularly, to an electromagnetic shielding material roll body supplied in a continuous roll sheet state for covering a large area such as a window glass of a large building and a manufacturing method thereof. .

  In recent years, electromagnetic waves generated from various electronic devices have a negative effect on the human body and malfunction of surrounding electronic devices has become a problem. Furthermore, with the spread of wireless LAN, communication data in buildings has been Therefore, it is necessary to prevent leakage and interception, and countermeasures against electromagnetic wave shielding 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 electronic devices leak to the 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).

Further, in Patent Document 5, when forming a fine mesh pattern of a copper thin film by the etching method of (1) above, a single wafer on which a predetermined mask pattern is formed in order to expose a resist (photocurable resin). A single wafer processing type exposure apparatus using an exposure mask of a type (photomask) is described.
Japanese Patent Laid-Open No. 10-075087 JP 11-170420 A JP 2004-221564 A WO2004 / 007810 JP 2003-295457 A

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, as an application of a conventional electromagnetic wave shielding material, an electromagnetic wave shielding film incorporated in an optical filter of a PDP in order to shield an electromagnetic wave generated from a PDP (plasma display) is a main one. In such a comparatively small device, the area of the electromagnetic shielding film used per unit becomes narrow. Moreover, the electromagnetic wave shielding film for PDP, etc. is produced by discontinuously manufacturing a mesh pattern of the screen size of PDP at regular intervals on the roll sheet surface, and a continuous mesh without a joint on the roll sheet surface. It has not been known to produce an electromagnetic shielding material composed of a pattern. For this reason, the technique which can provide the electromagnetic wave shielding material supplied in the continuous roll sheet | seat state for covering large areas, such as a window glass of a large-sized building, in low cost was calculated | required.

  The present invention has been made in view of the above circumstances, and is an electromagnetic wave shielding material supplied in a wide and continuous roll sheet state for covering a large area such as a window glass of a large building, which cannot be handled by a conventional manufacturing method. It is another object of the present invention to provide a manufacturing method thereof.

In order to solve the above-described problems, the present invention provides a developed silver mesh pattern generated by a photographic process in which developed silver is developed on at least one surface of a long transparent substrate, and electrolytic plating at least electrolytically plated thereon. An electromagnetic shielding material roll body provided with a metal mesh pattern having a layer and supplied in a roll state, wherein the developed silver mesh pattern is a continuous feed of the transparent base material, and the transparent Exposure through an exposure mask using a continuous exposure apparatus that can continuously expose the substrate without continually irradiating light, and can produce a continuous pattern with no joints, and then develop Produced by the above, the seamless base material is continuous in the longitudinal direction, and the metal mesh pattern is the continuous developed silver mesh pattern. It has at least an electrolytic plating layer on it, and is continuously provided in the longitudinal direction of the transparent substrate, and is made of a metal mesh or a metal thin film having a constant width that is in contact with both outer sides in the width direction of the metal mesh pattern. The power supply layer for electrolytic plating is continuously provided in the longitudinal direction of the transparent substrate for energization of electrolytic plating performed using an apparatus that performs electrolytic plating without interruption in a roll-to-roll continuous feed. An electromagnetic wave shielding material roll body is provided.

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.

The present invention also provides a metal mesh pattern having, on at least one surface of a long transparent substrate, a developed silver mesh pattern generated by a photographic process in which developed silver is developed and an electrolytic plating layer at least electrolytically plated thereon. Is a method for producing an electromagnetic shielding material roll body that is continuously provided in the longitudinal direction of the transparent base material and is supplied in the form of a roll, and a substance that deposits metallic silver by exposure and development. The transparent base material provided with the layer including the continuous feed of the transparent base material can be continuously exposed without intermittent light irradiation to the transparent base material, and the joint The developed silver mesh is seamlessly continuous in the longitudinal direction of the transparent substrate by exposing through an exposure mask using a continuous exposure apparatus that provides a continuous pattern with no pattern, and then developing. A pattern of a power supply layer for electrolytic plating comprising a pattern and a thin film or mesh of developed silver having a constant width that is in contact with both widthwise outer sides of the continuous developed silver mesh pattern and continuously provided in the longitudinal direction of the transparent substrate And a process of producing a raw roll in which the developed silver mesh pattern is formed, and after continuously feeding the transparent base material provided with the developed silver mesh pattern from the raw roll, electroplating without interruption by continuous feeding with a roll-to-roll And an electroplating step of forming an electroplating layer on the developed silver mesh pattern by energizing from the electroplating power feeding layer using an apparatus for performing electroplating and rewinding to form a roll body. The manufacturing method of the electromagnetic wave shielding material roll body characterized by the above is provided.

In the present invention, the metal mesh pattern formed by forming an electrolytic plating layer on a developed silver mesh pattern generated by a photographic process in which developed silver is developed on at least one surface of a long transparent substrate, A method of manufacturing an electromagnetic shielding material roll body that is continuously provided in the longitudinal direction of a transparent substrate and is supplied in a roll state, the layer containing a substance that deposits metallic silver by exposure and development The provided transparent base material is continuously fed out, and the transparent base material is continuously fed to the transparent base material, and exposure is continuously performed without intermittent light irradiation to the transparent base material. Can be continuously provided in the longitudinal direction of the transparent base material by exposure through an exposure mask using a continuous exposure apparatus that can obtain a continuous pattern with no joints, and then developing. The developed silver mesh pattern and a developed silver thin film or mesh having a constant width in contact with both outer sides in the width direction of the developed silver mesh pattern and continuously provided in the longitudinal direction of the transparent substrate. Electrolytic plating is performed by energizing the power feeding layer for electroplating using a device that generates a pattern of the power feeding layer for electroplating, and then continuously performing electroplating by roll-to-roll continuous feed. An electroplating layer is formed on the developed silver mesh pattern by a plating step, and then wound up again to form a roll body. An electromagnetic shielding material roll body manufacturing method is provided.

The continuous exposure apparatus includes a cylindrical drum made of a material that transmits light used for exposure in the photographic method, an exposure mask portion provided on an outer peripheral wall of the cylindrical drum, and an inside of the cylindrical drum. A device for irradiating light from the inside of the cylindrical drum to the transparent base material wound around the cylindrical drum.
Further, the continuous exposure apparatus includes a cylindrical drum, an exposure mask film on which a continuous pattern is formed, and an exposure light source disposed outside the cylindrical drum, and is wound around the cylindrical drum. An apparatus for irradiating light from the outside of the cylindrical drum to the transparent base material and the exposure mask film can also be used.

The generation of the developed silver mesh pattern of the transparent substrate of the original fabric roll, negative developing method of expressing developed silver in the exposed portions, by either developed silver to a portion which is not exposed is a positive type developing method of expressing It can be carried out.

  ADVANTAGE OF THE INVENTION According to this invention, the electromagnetic wave shielding material roll body supplied with the wide continuous roll sheet state for covering large areas, such as a window glass of a large sized building, and its manufacturing method can be provided. In addition, according to the present invention, the electromagnetic shielding material can be continuously manufactured and supplied by roll-to-roll, so that the manufacturing cost can be greatly reduced.

  In addition, when forming a mesh pattern by development and exposure, if a continuous exposure apparatus in which the feed of the transparent base material is continuous feed is used, an exposure apparatus of a single wafer processing method in which the feed of the transparent base material is intermittent feed Compared with the processing speed. Moreover, since there exists an advantage that the continuous pattern without a joint is obtained, the development silver mesh pattern etc. which were continuously provided in the longitudinal direction of the transparent base material can be formed easily. For this reason, productivity can be improved.

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 schematic view showing an example of an apparatus for continuously performing electroplating following exposure / development by roll-to-roll in the present invention. FIG. 3 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 of the present invention. FIG. 4 is a partial plan view showing an example of the arrangement of mesh patterns and power supply layers in an electromagnetic shielding material for PDP, for example, in the prior art. FIG. 5 is a schematic view showing an example of a continuous exposure apparatus used in the present invention. FIG. 6 is a schematic view showing another example of the continuous exposure apparatus used in the present invention.

(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. For this reason, a receiving tank 10 for receiving 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.

  An electromagnetic wave shielding material manufacturing apparatus 1A shown in FIG. 2 is an apparatus that continuously performs electrolytic plating following exposure and development. In the electromagnetic shielding material manufacturing apparatus 1A shown in FIG. 2, the raw roll 2A is a roll sheet 3 in which a layer (details will be described later) containing a substance that deposits metallic silver by exposure and development is provided on a long transparent substrate. Is rolled up into a roll. The roll sheet 3 fed out from the raw roll 2A is transferred from left to right in the figure by transfer rolls 4, 4, 4,. The roll sheet 3 is first transferred to the continuous exposure device 16 and baked (exposed) with a predetermined mask pattern. Here, the continuous exposure device 16 is a device that performs exposure while transporting the transparent substrate by continuous feeding, as will be described in detail later.

Next, the exposed roll sheet 3 is transferred to the developing device 17, and the developed silver that has been photographic developed is fixed in a mesh pattern shape. Next, after passing through the water washing tank 5 and being washed to remove unnecessary foreign matters and contaminants, it is transferred to at least the electrolytic plating tank 6 for performing a plating process.
In the electromagnetic shielding material manufacturing apparatus 1A of FIG. 2, the configuration from the electrolytic plating tank 6 to the electromagnetic shielding material roll body 15 is the same as that of the electromagnetic shielding material manufacturing apparatus 1 shown in FIG.

According to the configuration of FIG. 2, the development of the developed silver mesh pattern (exposure / development process) and the formation of the plating layer (plating process) are continuously performed during one roll-to-roll process. This can be implemented, and the processing speed can be further improved and the cost can be reduced.
In this embodiment, it is preferable that after the development silver mesh pattern is generated by the photographic manufacturing method, the plating process is continuously performed while the surface of the transparent substrate is kept wet. In this case, it is possible to reduce the occurrence of plating defects due to the minute bubbles adhering to the surface of the developed silver mesh pattern and obstructing the contact with the plating solution.
If necessary, an electroless plating bath (not shown) is disposed between the continuous exposure device 16 and the developing device 17 and the electrolytic plating bath 6, and there is nothing on the developed silver mesh pattern generated by exposure and development. A configuration in which after the electrolytic plating is performed, the electrolytic plating is further transferred to the electrolytic plating tank 6 to perform the electrolytic plating. Thus, an electromagnetic wave shielding material with higher performance can be obtained by using electroless plating and electrolytic plating in combination in the plating step.

  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. 4, 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. Such a conventional technique cannot cope with a technique of forming a continuous mesh pattern and continuously performing electrolytic plating.

  Therefore, in the present invention, as shown in FIGS. 1 and 2, the roll sheet 3 is continuously fed out from the exposed / developed original roll 2 or the unexposed original roll 2A, and the transfer rolls 4, 4,. In order to transfer continuously to the electroplating tank 6 by continuous feed and perform electroplating continuously without interruption, it was provided on at least one surface of the long transparent base material 21 as in the roll sheet 20 shown in FIG. The metal mesh pattern 22 is continuously provided in the longitudinal direction of the transparent base material 21, and the continuous power feeding layers 23 and 23 having a constant width continuous in the longitudinal direction of the transparent base material 21 are provided in the width direction of the metal mesh pattern 22. What was provided in contact with the both outer sides is used.

  Furthermore, in a more preferred embodiment of the present invention, as shown in FIG. 2, a continuous exposure device (details will be described later) 16 is provided in the previous stage of the electrolytic plating tank 6, and the roll sheet 3 is exposed using the continuous exposure device 16. Therefore, the transparent substrate can be transferred by continuous feeding throughout both the exposure / development process and the plating process, and the process can be continued without interruption.

  The continuous power supply layer 23 is in contact with the power supply rolls 7 and 7 serving as a cathode before and after the portion where the roll sheet 3 is introduced into the electrolytic plating tank 6. As a result, during electroplating, an electrolysis current is supplied to the mesh pattern 22 through the continuous power feeding layer 23, and plating by electroplating is performed on the developed silver mesh pattern and / or the electroless plating layer formed thereon. A layer is formed.

  The mesh pattern 22 is a developed silver mesh pattern generated by a photographic method in the exposed and developed original fabric roll 2 in FIG. That is, the raw fabric roll 2 has a developed silver mesh pattern and a fixed width metal mesh or metal thin film continuously provided in the longitudinal direction of the transparent substrate 21 on at least one surface of the long transparent substrate 21. The continuous power supply layer 23 made of is formed. In order to continuously provide the developed silver mesh pattern in the longitudinal direction of the transparent substrate 21, the development is performed after the continuous mesh pattern is baked by a continuous exposure apparatus (described in detail later) in the present invention.

Further, a developed silver mesh pattern 22 is generated on the roll sheet 3 fed out from the original roll 2A of FIG. 2 by a photographic method using a continuous exposure device 16 and a developing device 17. The roll sheet 3 at the position to be transferred to the electrolytic plating tank 6 was continuously provided on at least one surface of the long transparent base material 21 in the longitudinal direction of the developed silver mesh pattern and the transparent base material 21. A continuous power supply layer 23 made of a metal mesh or metal thin film having a constant width is formed.
Here, the continuous power supply layer 23 does not have to be a fine line pattern, in other words, a pattern as fine as the developed silver mesh pattern 22 is not required. It can also be provided on 2A. However, as a more preferable form, it is preferable to produce the continuous feeding layer 23 as a developed silver thin film or mesh together with the developed silver mesh pattern 22 by using the continuous exposure device 16 and the developing device 17 by a photographic method. .

  Further, the mesh pattern 22 in the electromagnetic wave shielding material roll body 15 is obtained by forming a plated layer on at least an electroplated developed silver mesh pattern by electrolytic plating. Although the width | variety of the continuous electric power feeding layer 23 is based also on the width | variety of the electric power feeding roll 7 currently used, it is about 15-100 mm, More preferably, it is 15-80 mm, More preferably, it is 20-60 mm.

(Transparent substrate)
The transparent substrate 21 used in the present invention is preferably a transparent substrate having transparency in the visible region and generally having a total light transmittance of 90% or more. 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 substrate 21 include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), acrylic resins, epoxy resins, fluorine resins, silicone resins, polycarbonate resins, Single-layer film having a thickness of 50 to 300 μm made of acetate resin, triacetate resin, polyarylate resin, polyvinyl chloride, polysulfone resin, polyether sulfone resin, polyimide resin, polyamide resin, polyolefin resin, cyclic polyolefin resin, or the like A composite film having a plurality of layers made of a resin is exemplified.

(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.

(Exposure method)
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 above-described method of exposing with laser light, 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.

(Exposure equipment)
As an exposure apparatus using the above exposure method, there are a single wafer processing type exposure apparatus using a single wafer type exposure mask (photomask) and a continuous exposure apparatus capable of forming a continuous pattern. A single wafer processing type exposure apparatus uses a single wafer type exposure mask (photomask) on which a predetermined mask pattern is formed, intermittently feeds a roll sheet to the exposure apparatus, and evacuates the inside of the apparatus for exposure. After the mask and the substrate are brought into close contact with each other and no gap is formed, exposure is performed with, for example, ultraviolet rays. In a single wafer processing type exposure apparatus, vacuum exhaust, exposure, and release to the atmosphere are intermittently performed, so that the processing speed is slow and a seamless continuous pattern cannot be obtained.

On the other hand, in the present invention, as illustrated in FIGS. 5 and 6, continuous exposure apparatuses 60 and 70 capable of continuously forming patterns are used.
As shown in FIG. 1, these continuous exposure apparatuses 60 and 70 are provided separately from the electromagnetic shielding material manufacturing apparatus 1 when performing the exposure / development process separately from the roll-to-roll process for performing the plating process. Continuous exposure and development are performed by an apparatus to produce the original roll 2. As shown in FIG. 2, when the exposure / development and the electrolytic plating are continuously performed by roll-to-roll, the continuous exposure device 16 incorporated in the electromagnetic shielding material manufacturing apparatus 1A is shown in FIGS. The continuous exposure apparatuses 60 and 70 exemplified in FIG.
In the drawings showing these continuous exposure apparatuses 60 and 70, the transparent base material used for the exposure will be described with the common reference numerals 64 and 74 without particularly distinguishing the shape of the pattern.

  A continuous exposure apparatus 60 shown in FIG. 5 includes a cylindrical drum 61 made of a material that transmits light used for exposure in the photographic manufacturing method, an exposure mask portion 62 provided on the outer peripheral wall of the cylindrical drum 61, and the inside of the cylindrical drum 61. And an exposure light source 63 disposed on the surface of the cylindrical drum 61, and the transparent substrate 64 wound around the cylindrical drum 61 is exposed by light emitted from the light source 63 inside the cylindrical drum 61. In the continuous exposure apparatus 60, a light source cover 65 having an opening 66 that transmits light in a specific irradiation direction can be provided around the exposure light source 63. The pattern for exposing the transparent substrate 64 is determined by the pattern of the portion of the exposure mask portion 62 that transmits light. The exposure mask portion 62 is disposed on the cylindrical drum 61 by, for example, being provided on the surface (inner surface or outer surface) of the outer peripheral wall of the cylindrical drum 61, or being inserted or sandwiched inside the outer peripheral wall. FIG. 5 is a diagram illustrating the case where the exposure mask portion 62 is provided on the outer surface of the outer peripheral wall of the cylindrical drum 61.

  In this continuous exposure apparatus 60, the cylindrical drum 61 rotates at the same speed as the transparent substrate 64 that is continuously transferred, so that exposure is performed at locations where each part of the transparent substrate 64 is wound around the cylindrical drum 61. During this time, the pattern of the exposure mask portion 62 on the transparent base material 64 (the pattern of the portion that transmits light and the portion that blocks light) is not shifted, and the exposure for the required time can be continued. The light source 63 used in the exposure apparatus can be appropriately selected depending on the spectral characteristics and sensitivity of the silver halide emulsion contained in the silver halide emulsion layer. For example, a tungsten lamp, an ultraviolet lamp, a fluorescent lamp, a xenon lamp, etc. Can be used. At the time of exposure, the light source cover 65 does not rotate, and the opening 66 always faces in a certain direction (right direction in FIG. 5). 63 light is blocked by the light source cover 65. That is, the exposure of the transparent base material 64 by the light source 63 of the exposure apparatus 60 is performed within a certain range 67 where the transparent base material 64 is wound around the surface of the cylindrical drum 61 on its transfer path. And time control can be performed reliably.

6 includes a cylindrical drum 71, an exposure mask film 72 on which a continuous pattern is formed, and an exposure light source 73 disposed outside the cylindrical drum 71. In this apparatus, the transparent substrate 74 and the exposure mask film 72 wound around the cylindrical drum 71 are irradiated with light from the outside of the cylindrical drum 71 to expose the transparent substrate 74.
The exposure mask film 72 forms a mesh pattern to be a mask on a transparent resin film by a known method such as a photolithographic method using reduced exposure, and is exposed by being superposed on the transparent substrate 74 and the cylindrical drum 71. Thereafter, the exposure mask film 72 is cut off from the transparent base material 74, wound up, and used repeatedly.
When the light source 73 is outside the cylindrical drum 71, the transparency of the cylindrical drum 71 is not particularly limited and may be opaque.

  The continuous exposure apparatus 70 can be provided with a light source cover 75 having an opening 76 that transmits light in a specific irradiation direction around the exposure light source 73, whereby the transparent substrate 74 is exposed by the light source 73. Is performed within a certain range 77 where the transparent base material 74 is wound around the surface of the cylindrical drum 71 on the transfer path, so that the exposure light quantity and time can be controlled reliably. Here, as the light source 73, the same light source 63 as that of the above-described continuous exposure apparatus 60 can be used.

The continuous exposure apparatus 70 continuously transfers the superposed transparent base material 74 and the exposure mask film 72 while being wound around the cylindrical drum 71. Therefore, the continuous exposure apparatus 70 can be transferred while applying appropriate tension to both. The speed can be easily controlled, and the pattern of the exposure mask film 72 on the transparent substrate 74 (light-transmitting portion and light-shielding portion) is exposed while the portions of the transparent substrate 74 are wound around the cylindrical drum 71. Therefore, the exposure for the required time can be continued.
In addition to the continuous exposure apparatuses 60 and 70 exemplified above, for example, the superimposed transparent base material and exposure mask film are continuously exposed using a light source while being continuously conveyed along a linear path. An apparatus or the like can also be used. Further, the number of light sources for exposure is not particularly limited, and a plurality (in a plurality of locations) may be provided as necessary.

The continuous exposure apparatuses 60 and 70 have an advantage that the processing speed is higher than that of a conventional single wafer processing type exposure apparatus, and a continuous pattern having no joints can be obtained. In the present invention, in order to produce a wide and continuous roll sheet electromagnetic shielding material for covering a wide area such as a large building window glass, it is necessary to form a continuous seamless mesh pattern, When the developed silver mesh pattern 22 is formed on the transparent substrate 21, continuous exposure devices 60 and 70 are used in the exposure prior to development.
In the present invention, it is also possible to form a continuous feed layer 23 having a constant width formed on both outer sides of the mesh pattern 22 in the same process as the development silver mesh pattern. As a result, the processing speed can be further improved.

  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 compounds described in 474 to 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, polyhydroxybenzenes such as hydroquinone, catechol, pyrogallol, methylhydroquinone, chlorohydroquinone, 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 dm2.
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.

  According to the present invention, it is possible to manufacture an electromagnetic shielding material that is supplied in a wide and continuous roll sheet state to cover a large area such as a window glass of a large building, which cannot be handled by a conventional manufacturing method. There are significant benefits to 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. In this invention, it is the schematic which shows an example of the apparatus which performs electrolytic plating continuously after exposure and image development with a roll to roll. It is a fragmentary top view which shows an example of arrangement | positioning of the mesh pattern and electric power feeding layer in the electromagnetic wave shielding material roll body of this invention. It is a partial top view which shows an example of arrangement | positioning of the mesh pattern and electric power feeding layer in the electromagnetic wave shielding material for PDP in a prior art, for example. It is the schematic which shows an example of the continuous exposure apparatus used by this invention. It is the schematic which shows another example of the continuous exposure apparatus used by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A ... Electromagnetic-shielding material manufacturing apparatus 2, 2A ... Original fabric roll, 3 ... Roll sheet, 4 ... Transfer roll, 5 ... Water washing tank, 6 ... Electrolytic plating tank, 7 ... Feed roll, 8 ... Positive electrode plate DESCRIPTION OF SYMBOLS 9 ... Electrolytic plating solution, 10 ... Receiving tank, 11 ... Circulation pump, 12 ... Filter, 13 ... Water washing tank, 14 ... Dryer, 15 ... Electromagnetic wave shielding material roll body, 16 ... Continuous exposure apparatus, 17 ... Developing apparatus 20 ... roll sheet according to the present invention, 21 ... transparent substrate, 22 ... mesh pattern, 23 ... continuous feeding layer, 60 ... continuous exposure device, 61 ... cylindrical drum, 62 ... exposure mask part, 63 ... light source for exposure, 64 DESCRIPTION OF SYMBOLS ... Transparent base material, 65 ... Light source cover, 70 ... Continuous exposure apparatus, 71 ... Cylindrical drum, 72 ... Exposure mask film, 73 ... Light source for exposure, 74 ... Transparent base material, 75 ... Light source cover.

Claims (7)

A metal mesh pattern having a developed silver mesh pattern produced by a photographic process in which developed silver is developed and an electrolytic plating layer at least electrolytically plated thereon is provided on at least one surface of the long transparent substrate. And an electromagnetic shielding material roll body supplied in a roll state,
The developed silver mesh pattern is a continuous pattern in which the transparent base material is continuously fed, and the transparent base material can be continuously exposed without intermittent light irradiation. Produced through exposure through an exposure mask using a continuous exposure apparatus obtained, and then developed, continuously in the longitudinal direction of the transparent substrate,
The metal mesh pattern has at least an electrolytic plating layer on the continuous developed silver mesh pattern, and is continuously provided in the longitudinal direction of the transparent substrate, and both the width directions of the metal mesh pattern are provided. The power supply layer for electrolytic plating made of a metal mesh or metal thin film with a constant width in contact with the outside is used for energization of electrolytic plating performed using an apparatus for performing continuous electroplating by roll-to-roll continuous feed. An electromagnetic wave shielding material roll provided continuously in the longitudinal direction of the material.   2. The electromagnetic wave shielding material roll according to claim 1, wherein the developed silver mesh pattern is generated by a negative development method in which developed silver is developed in an exposed portion.   2. The electromagnetic wave shielding material roll 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. A metal mesh pattern having a developed silver mesh pattern generated by a photographic process in which developed silver is developed and an electrolytic plating layer at least electrolytically plated thereon is formed on at least one surface of a long transparent substrate. A method of manufacturing an electromagnetic shielding material roll body that is continuously provided in the longitudinal direction of the material and is supplied in a roll state,
A transparent substrate provided with a layer containing a substance that deposits metallic silver by exposure and development, the feeding of the transparent substrate is continuous feeding, and the irradiation of light to the transparent substrate continues without interruption. Can be exposed and exposed through an exposure mask using a continuous exposure apparatus that can obtain a seamless continuous pattern, and then developed, thereby seamlessly connecting in the longitudinal direction of the transparent substrate. For developed electroplating comprising a developed silver mesh pattern, and a developed silver thin film or mesh having a constant width provided in contact with both widthwise outer sides of the continuous developed silver mesh pattern and continuously provided in the longitudinal direction of the transparent substrate. A process of manufacturing a raw roll in which a pattern of the power feeding layer is generated;
After continuously feeding the transparent base material provided with the developed silver mesh pattern from the raw roll, using an apparatus that performs continuous electroplating with a roll-to-roll continuous feed, from the power feeding layer for electrolytic plating A method for producing an electromagnetic shielding material roll body comprising at least an electroplating step of energizing to form an electrolytic plating layer on the developed silver mesh pattern and winding it again to form a roll body. On at least one surface of the long transparent substrate, a metal mesh pattern formed by forming an electrolytic plating layer on a developed silver mesh pattern generated by a photographic process in which developed silver is expressed is the length of the transparent substrate. A method for producing an electromagnetic shielding material roll body that is continuously provided in a direction and is supplied in a roll state,
A transparent base material provided with a layer containing a substance that deposits metallic silver by exposure and development is continuously fed out, and the transparent base material is continuously fed to the transparent base material. By exposing the light through an exposure mask using a continuous exposure apparatus that can be continuously exposed without intermittent light irradiation and can obtain a continuous continuous pattern, and then developing, the transparent The developed silver mesh pattern provided continuously in the longitudinal direction of the base material, and the width of both sides of the continuously provided developed silver mesh pattern in the width direction and continuous in the longitudinal direction of the transparent base material A pattern of a power supply layer for electrolytic plating made of a developed silver thin film or mesh of a certain width provided in succession, and then using an apparatus for performing electroplating without interruption with continuous feed by roll-to-roll Then, an electroplating layer is formed on the developed silver mesh pattern by an electroplating process in which electroplating is performed by energizing the power supply layer for electroplating, and then wound again to form a roll body. Manufacturing method of electromagnetic shielding material roll body.   6. The method for producing an electromagnetic wave shielding material roll according to claim 4, wherein the developed silver mesh pattern is generated by a negative developing method in which developed silver appears in an exposed portion.   The method for producing an electromagnetic wave shielding material roll according to claim 4 or 5, wherein the development silver mesh pattern is generated by a positive development method in which developed silver appears in a portion not exposed to light.

Images