JP2009185342A - Conductive material precursor, and conductive material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive material which has excellent conductivity and adhesive properties upon plating, also achieves an legible image without being influenced by interior light and outdoor daylight, has satisfactory color reproducibility, and has satisfactory adhesive properties with a functional layer, and to provide a method for producing the same. <P>SOLUTION: Regarding the conductive material precursor in which the surface of a support is at least provided with a physical development nucleus layer and a silver halide emulsifier layer in this order, the physical development nucleus layer comprises amino group-containing latex. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a conductive material precursor for obtaining a conductive material that can be used in applications such as an electromagnetic wave shielding material, an antenna circuit, a touch panel, and an electronic circuit, and a conductive material manufactured using the conductive material precursor. .

  In recent years, with the rapid development of the information-oriented society, technologies related to information-related devices have rapidly advanced and become popular. Of these, display devices are used for televisions, personal computers, information displays for stations, airports, and other information. In particular, plasma displays have attracted attention in recent years.

  In such an information society, there is a concern about the influence of electromagnetic waves radiated from these display devices. For example, the influence on surrounding electronic devices and the influence on the human body are considered. In particular, the impact on human health cannot be ignored, and there is a need to reduce the strength of the electromagnetic field applied to the human body, and various transparent conductive materials have been developed to meet such demands. Has been. For example, JP-A-9-53030, JP-A-11-122024, JP-A 2000-294980, JP-A 2000-357414, JP-A 2000-329934, JP-A 2001-38843, JP-A-2001-47549, JP-A-2001-51610, JP-A-2001-57110, JP-A-2001-60416, and the like.

  As a method for producing these transparent conductive materials, a conductive metal such as silver, copper, nickel, or indium is formed on a transparent resin film by sputtering, ion plating, ion beam assist, vacuum deposition, or wet coating. A method of forming a metal thin film on the substrate, a method of obtaining a conductive mesh by providing a resist pattern layer on a transparent support bonded to a metal foil, or a conductive material such as metal or conductive carbon A method of forming an image in a stripe or mesh form by printing a substance is known.

  As another method, a method using a silver salt photographic light-sensitive material using a silver salt diffusion transfer method as a transparent conductive material precursor has been proposed in recent years. For example, Japanese Patent Application Laid-Open No. 2003-77350 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2005-250169 (Patent Document 2) include a soluble silver salt forming agent and a reducing agent in an alkaline solution from a silver halide emulsion layer. A technique for forming a metallic silver pattern by acting is disclosed. Patterning by this method can reproduce a uniform line width, and since silver has the highest conductivity among metals, higher conductivity can be obtained with a narrower line width than other methods. That is, it is possible to achieve both high transmittance and high conductivity.

  Another major feature of silver is that it has the highest visible light reflectance among metals and is also used in mirrors. Since the silver salt diffusion transfer method forms a high-density silver film, the surface is specular and the reflectance is high. Accordingly, when such a transparent conductive material is used for a display filter, unnecessary light such as room light or outside light is reflected, and the bright room contrast of the fluoroscopic image is lowered, thereby making it difficult to see the image. Further, there are cases where the image is not tightened and the gradation expression in the dark part of the image and the color reproducibility are poor.

  As a means for solving this problem, a blackening treatment for reducing the reflectance of metallic silver is used. However, since the metal silver pattern is blackened after being formed, the adhesion surface side between the metal silver pattern and the support cannot be blackened, and the metal silver pattern viewed from the support remains silver. For this reason, there arises a limitation in manufacturing a display in which a surface having a low reflectance due to the blackening process must be installed outside (a side viewed by a person). Therefore, blackening of the metallic silver pattern and the bonding surface side of the support has been desired.

  On the other hand, a metal silver pattern produced from a silver salt photographic light-sensitive material using a silver salt diffusion transfer method is characterized by having high electrical conductivity, but may be plated in order to further increase electrical conductivity. In addition, in order to obtain higher conductivity, when a high-thickness plating is performed, the metal silver pattern may be easily peeled off from the support due to the stress caused by the plating. As one means for improving the adhesion during plating, there is a method in which a physical development nucleus layer contains a binder. JP-A-2003-77350 (Patent Document 1) uses gelatin as a binder in the physical development nucleus layer. It is described that a protein such as is contained. As a result, good adhesion between the metal silver pattern and the support was obtained, but there was a problem that electroconductivity was reduced or electroless plating was difficult due to surface contamination by proteins. In order to solve this problem, Japanese Patent Application Laid-Open No. 2005-250169 (Patent Document 2) discloses a technique for ensuring the adhesiveness of a metallic silver pattern without containing a protein in the physical development nucleus layer. . However, when the above-mentioned metal silver pattern was plated with a high film thickness, the adhesion between the metal pattern after plating and the support was insufficient. Therefore, there has been a demand for a conductive material that does not impair electrical conductivity, has excellent adhesion to a metal pattern after plating, and has a blackened adhesive surface side with the support of the metal silver pattern.

  Japanese Patent Application Laid-Open No. 2007-87625 (Patent Document 3) discloses a technique regarding blackening of the adhesive surface side with the support of the metallic silver pattern.

  In addition, when using a conductive material as an electromagnetic shielding film for a plasma display panel, the front surface of the plasma display panel is combined with a functional film having performances such as antireflection, antiglare, hard coat, and ultraviolet absorption. Installed as a filter. For example, the ultraviolet absorbing film is used to prevent deterioration of the transparent film and other materials due to ultraviolet rays. The UV absorbing film is formed by dispersing an organic UV absorber such as benzotriazole or benzophenone in a dispersing agent or dissolving it in a suitable solvent on the transparent film, and forming an UV absorbing layer on the transparent film. Can be obtained. Furthermore, the plasma display panel filter is required to be as thin as possible from the viewpoint of improving the image quality and reducing the weight. Therefore, for the purpose of reducing the number of plastic films, it is required to directly coat a functional layer such as an ultraviolet absorbing layer on the electromagnetic wave shielding film without using the functional film as described above. Yes.

  However, in the conductive material produced by subjecting the above-mentioned silver salt photographic light-sensitive material to image exposure and development and then metal plating, the surface of the conductive material from which a water-soluble polymer such as gelatin was obtained was obtained. There were cases where it remained. For this reason, the surface of the conductive material obtained by this method has a problem that the affinity with a substance having low polarity is very low and the adhesiveness with a substance having low polarity is weak. In the conductive material manufactured using the silver salt diffusion transfer method of Patent Documents 1 and 3 described above, a hydrophilic colloid layer containing a hydrophilic polymer such as a silver halide emulsion layer constituting the conductive material precursor Is removed at the time of development, the adhesion problem described above is less than that of conductive material precursors that do not use the silver salt diffusion transfer method, but adhesion to the functional layer coated on the conductive material. In some cases, the image itself may peel off even with a slight force.

In the conductive material produced using the silver salt diffusion transfer method, in the above-mentioned Patent Document 2, proteins such as gelatin are contained in the physical development nucleus layer and the undercoat layer between the support and the physical development nucleus layer. However, even with the conductive material thus obtained, the adhesion with the functional layer as described above was not sufficiently satisfactory.
Japanese Patent Laying-Open No. 2003-77350 (first page) Japanese Patent Laying-Open No. 2005-250169 (first page) JP 2007-87625 A (first page)

  Accordingly, the object of the present invention is to provide excellent conductivity and adhesion between the metal pattern after plating and the support, and is easy to see the image and is excellent in color reproducibility without being influenced by room light or outside light. Then, it is providing the electroconductive material precursor and electroconductive material from which the electroconductive material with favorable adhesiveness with a functional layer is obtained.

  A conductive material precursor having at least a physical development nucleus layer and a silver halide emulsion layer in this order on a transparent support, wherein the physical development nucleus layer contains an amino group-containing latex. And the conductive material manufactured using the same has achieved the object of the present invention.

  According to the present invention, it has excellent conductivity and adhesion between the metal pattern after plating and the support, and it is easy to see the image without being affected by room light or outside light, and has good color reproducibility and functionality. It is possible to provide a conductive material precursor and a conductive material from which a conductive material having good adhesion to a layer can be obtained.

  The conductive material precursor of the present invention has at least a physical development nucleus layer and a silver halide emulsion layer in this order on a transparent support.

  The amino group-containing latex contained in the physical development nucleus layer of the present invention will be described. A normal latex is produced by emulsion polymerization of a monomer in the presence of a surfactant or a protective colloid. The types are broadly divided into vinyl polymer and synthetic rubber. The former includes acrylic, polystyrene, vinyl acetate, vinylidene chloride, and vinyl chloride, and the latter includes styrene-butadiene copolymer mainly composed of diene monomer. Methyl methacrylate butadiene copolymer, acrylonitrile butadiene copolymer, and the like. These are the main monomers and often incorporate other types of monomers for modification purposes. In addition to the conventional single stage feed (SSF) polymerization that keeps the polymerization composition constant, the polymer composition of the core (core) and shell (shell) is achieved by performing multistage feed (MSF) polymerization that changes the composition in the middle. However, the high functionality of latex has also been achieved by forming different core-shell structures.

  In the present invention, an amino group-containing latex can be produced by using an amino group-containing monomer as the monomer. Among them, the amino group is preferably primary or secondary, and may contain two or more types. Specific methods for producing these amino group-containing latexes include, for example, JP-A-6-166735, JP-A-2000-248019, JP-A-2001-277710, JP-A-2002-322218, JP-A-2003. -192722, JP-A-2005-48185, and the like. Although there is no restriction | limiting in particular in an average particle diameter, It is preferable that it is 0.3 micrometer or less. Examples of commercially available products include UCR-319SX, UW-223SX, UW-550CS manufactured by Taisei Fine Chemical Co., Ltd., and SK-1000 manufactured by Nippon Shokubai Co., Ltd. In particular, the type that contains functional groups that react with amino groups in the same particle, such as the Acryt series manufactured by Taisei Fine Chemical Co., Ltd., and that self-crosslinks with a dry coating film, the metal pattern after plating and the support It is preferable in terms of adhesion and adhesion between the functional layer and the metal pattern.

The preferable addition amount of the amino group-containing latex of the present invention is 10 to 100 mg / m ² , more preferably 30 to 70 mg / m ² . If the addition amount is small, the blackening of the metallic silver is insufficient, and if it is too much, the conductivity may be lowered.

In the conductive material precursor used in the present invention, fine particles (having a particle size of about 1 to several tens of nm) made of heavy metals or sulfides thereof are used as the physical development nuclei. 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 support on which the undercoat layer is formed by a coating method or an immersion treatment method. 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 m ^{2 in} terms of solid content.

  The coating liquid used for applying the physical development nuclei of the present invention to a transparent support may contain a hydrophilic polymer for various purposes such as stabilization of the physical development nuclei and easy application. Specific examples include polyvinyl alcohol, hydroxyethyl cellulose, hydroxypropyl cellulose, polyacrylic acid, and polyvinyl pyrrolidone. When these hydrophilic polymers are contained, the amount is preferably about 5 to 100% by mass relative to the solid content of the amino group-containing latex of the present invention.

The physical development nucleus layer used in the present invention may contain a crosslinking agent. Examples of the crosslinking agent include aldehydes such as formalin, glyoxal, malealdehyde and glutaraldehyde, N-methylol compounds such as urea and ethylene urea, aldehyde equivalents such as mucochloric acid and 2,3-dihydroxy-1,4-dioxane. , Compounds having active halogen such as 2,4-dichloro-6-hydroxy-s-triazine salt, divinyl sulfone, divinyl ketone and N, N, N-triacryloylhexahydrotriazine, active three-membered ring One or more of various compounds such as compounds having two or more ethyleneimino groups or epoxy groups in the molecule and dialdehyde starch as a polymer hardener can be used. Among these cross-linking agents, dialdehydes such as glyoxal, glutaraldehyde, 3-methylglutaraldehyde, succinaldehyde, and adipaldehyde are preferable, and glyoxal and glutaraldehyde are more preferable. Crosslinking agent is preferably be contained 1 to 20 mg / m ^2, in particular 3-10 mg / m ² is preferred.

  Further, the physical development nucleus layer contains known photographic additives as described in Research Disclosure # 17643 (December 1978) and 18716 (November 1979), 308119 (December 1989). be able to.

  There are no particular restrictions on the physical development nucleus layer coating method, and it can be applied by dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, extrusion coating, or the like. .

  For forming the silver halide emulsion grains contained in the silver halide emulsion layer of the present invention, methods well known in the art such as forward mixing, back mixing and simultaneous mixing are used. Among them, the so-called controlled double jet method, which is a kind of simultaneous mixing method and keeps pAg in a liquid phase to be formed constant, is preferable in that silver halide emulsion grains having a uniform particle diameter can be obtained. In the present invention, the average grain size of preferable silver halide emulsion grains is 0.25 μm or less, particularly preferably 0.05 to 0.2 μm. There is a preferable range for the halide composition of the silver halide emulsion used in the present invention, and it is preferable that the chloride content is 80 mol% or more, and it is particularly preferable that 90 mol% or more is chloride.

  The silver halide emulsion layer contains a hydrophilic polymer as a binder. As the hydrophilic polymer here, any polymer can be selected as long as it easily swells with the developer and allows the developer to easily penetrate into the underlying physical development nucleus layer. Preferred hydrophilic polymers include, for example, gelatin, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polysaccharides such as starch, cellulose and derivatives thereof.

  When the amount of the hydrophilic polymer contained in the silver halide emulsion layer is small, the coating property is adversely affected, and stable silver halide grains cannot be obtained. On the other hand, if the amount is too large, a decrease in conductivity and a decrease in plating property can be observed when forming a plating film. A preferred amount is such that the mass ratio of silver halide (in terms of silver nitrate) and binder (silver nitrate / total binder) is 2.0 or more, more preferably 2.4 to 5.5.

  In the silver halide emulsion layer, known photographic additives can be used for various purposes. These are described in Research Disclosure Item 17643 (December 1978) and 18716 (November 1979), 308119 (December 1989) or cited.

  In the production of the silver halide emulsion in the present invention, a sulfite, a lead salt, a thallium salt, a rhodium salt or a complex salt thereof, an iridium salt or a complex salt thereof is formed in the process of forming silver halide grains or physical ripening as necessary. A salt of a group VIII metal element or a complex salt thereof may coexist. Further, it can be sensitized with various chemical sensitizers, and methods commonly used in the art such as sulfur sensitization method, selenium sensitization method and noble metal sensitization method can be used alone or in combination. In the present invention, the silver halide emulsion can be dye-sensitized as necessary. Furthermore, known photographic additives can be used for various purposes. These are described in Research Disclosure # 17643 (December 1978) and 18716 (November 1979), 308119 (December 1989) or cited references.

  In the conductive material precursor of the present invention, a non-photosensitive layer can be provided between the silver halide emulsion layer and the physical development nucleus layer or on the silver halide emulsion layer. These non-photosensitive layers are layers having a hydrophilic polymer as a main binder. The hydrophilic polymer here is the same as the binder used for the silver halide emulsion layer described above, and easily swells with the developer, and easily penetrates into the lower silver halide emulsion layer and the physical development nucleus layer. Any one can be selected.

  Specifically, gelatin, albumin, casein, polyvinyl alcohol, or the like can be used. Particularly preferred hydrophilic polymers are proteins such as gelatin, albumin and casein. In order to sufficiently obtain the effects of the present invention, the amount of the hydrophilic polymer of the non-photosensitive layer is preferably in the range of 20 to 100% by weight, particularly 30 to 30% by weight based on the total binder amount of the silver halide emulsion layer. 80 mass% is preferable.

  In addition, the non-photosensitive layer (intermediate layer) between the physical development nucleus layer and the silver halide emulsion layer, which is provided as necessary, is subjected to silver complex diffusion transfer development with an alkali processing solution, and the physical development nucleus layer when washed with warm water. It is suitable for facilitating the removal of the unnecessary layer above.

  The conductive material precursor in the present invention may be provided with a backing layer on the opposite side of the support from the silver halide emulsion layer, if necessary.

  As the conductive material precursor, it is preferable to use a non-sensitizing dye or pigment having an absorption maximum in the photosensitive wavelength region of the silver halide emulsion layer as a halation for improving image quality or an irradiation prevention agent. The antihalation agent can be contained in an intermediate layer between the silver halide emulsion layer and the support or in a backing layer. The irradiation inhibitor is preferably contained in the silver halide emulsion layer. The addition amount can be varied within a wide range as long as the desired effect can be obtained. For example, when it is contained in the backing layer as an antihalation agent, a range of 0.02 to 1 g per square meter is desirable, preferably a maximum. The optical density at the absorption wavelength is 0.5 or more.

  The transparent support used for the conductive material precursor of the present invention is not particularly limited as long as it has transparency in the visible region, but a plastic resin film having a total light transmittance of 60% or more is preferable. Examples thereof include polyester resins such as polyethylene terephthalate, diacetate resins, triacetate resins, acrylic resins, polycarbonate resins, polyvinyl chloride, polyimide resins, cellophane, celluloid and other plastic resin films, and glass plates. Furthermore, in the present invention, an undercoat layer or an antistatic layer for improving the adhesion to the silver halide emulsion layer can be provided on the support, if necessary.

  Examples of the method for producing the conductive material using the conductive material precursor include formation of a silver thin film having a mesh pattern. In this case, the silver halide emulsion layer is exposed in a mesh pattern, and as an exposure method, a transparent original having a mesh pattern and a conductive material precursor are exposed in close contact, or scanning is performed using various laser beams. There are exposure methods. In the above-described method of exposing with laser light, for example, a blue semiconductor laser (also referred to as a violet laser diode) having an oscillation wavelength of 400 to 430 nm can be used.

  After the exposure, the conductive material precursor is subjected to silver complex salt diffusion transfer development with an alkaline processing liquid, and washed with warm water to remove a layer provided on a physical development nucleus layer such as a silver halide emulsion layer. This alkaline processing liquid is a liquid used when performing silver complex diffusion transfer development which is physical development processing. As a method for removing the layer provided on the physical development nucleus layer, there is a method of removing by washing 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. In addition, the method of transferring and peeling with a release paper or the like is to squeeze the excess alkali processing solution (silver complex salt diffusion transfer developer) on the silver halide emulsion layer in advance with a roller or the like, and the silver halide emulsion layer and the release paper. Is a method in which a silver halide emulsion layer or the like is transferred from a plastic resin film to a release paper and peeled off. As the release paper, water-absorbing paper or non-woven fabric, or paper having a water-absorbing void layer formed of fine pigment such as silica and binder such as polyvinyl alcohol on the paper is used.

  Next, a developing solution for silver salt diffusion transfer development will be described. The developer is an alkaline solution containing a soluble silver complex salt forming agent and a reducing agent. 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 for reducing the soluble silver complex salt to deposit metallic silver on the physical development nucleus. .

  Soluble silver complex forming agents include thiosulfates such as ammonium thiosulfate and sodium thiosulfate, thiocyanates such as sodium thiocyanate and ammonium thiocyanate, sulfites such as sodium sulfite and potassium hydrogen sulfite, oxadoridones, 2-mercaptobenzoic acid and derivatives thereof, cyclic imides such as uracil, alkanolamines, diamines, mesoionic compounds described in JP-A-9-171257, described in US Pat. No. 5,200,294 Such thioethers, 5,5-dialkylhydantoins, alkyl sulfones, and others. H. Examples thereof include compounds described in 474-475 (1977) of The Theory of the Photographic Process, 4th edition, edited by James.

  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, ascorbic acid and its derivatives, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1-phenyl-3-pyrazolidone, 1- Examples include 3-pyrazolidones such as phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone, p-methylaminophenol, p-aminophenol, p-hydroxyphenylglycine, and p-phenylenediamine.

  The soluble silver complex salt forming agent and the reducing agent may be contained in a coating solution for coating a physical development nucleus layer or a coating solution for coating a silver halide emulsion layer. Or may be contained in the alkali treatment liquid, and further may be contained in a plurality of positions. The above-described soluble silver complex salt forming agent and reducing agent are preferably contained in at least the alkali treatment liquid.

  The content of the soluble silver complex salt forming agent in the alkali processing 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 treatment liquid is preferably 10 or more, more preferably 11-14. In order to adjust to a desired pH, an alkali agent such as sodium hydroxide or potassium hydroxide, or a buffering agent such as phosphoric acid or carbonic acid is contained alone or in combination. The developer of the present invention preferably contains a preservative such as sodium sulfite or potassium sulfite. In the present invention, the alkaline processing liquid for silver complex diffusion transfer development may be applied by an immersion method or a coating method. In the immersion method, for example, a conductive material precursor provided with a physical development nucleus layer and a silver halide emulsion layer is transported while being immersed in an alkaline processing liquid stored in a large amount in a tank. In the method, for example, about 40 to 120 ml of an alkali treatment solution is applied on a silver halide emulsion layer per square meter.

  In the present invention, the preferred mode for improving the electrical conductivity and the metallic luster is suitably 18 to 22 ° C. when the alkaline processing liquid is applied. The application time of the alkali treatment liquid is suitably about 20 seconds to 3 minutes. This aspect is particularly suitable in the case of the immersion method.

  The light reflectance measurement of the conductive material of the present invention is not performed by forming a silver thin film in a stripe or mesh shape, but using a silver thin film formed on the entire surface. A means for forming a silver thin film on the entire surface can be obtained by developing without exposure.

  The visibility of the image on the display and the good reproducibility of the image when the conductive material is attached can be determined by the light reflectance of the conductive material. The light reflectance can be measured using a commercially available reflective spectrophotometer. By reducing the reflectance, the image on the display is easy to see and the color reproduction of the image is good. Further, since the light that can be recognized by human eyes is in the wavelength range of 400 to 800 nm, the reflectance of light in this region is measured. In the measurement of reflectance, magnesium oxide pellets are used as a reference, and the magnesium oxide pellets can be obtained from a manufacturer or the like that sells a spectrophotometer.

  When the material to be measured transmits light, the reflectivity of the sample holder is adversely affected, so a reference magnesium oxide pellet is placed behind the conductive material for measurement.

  In the above reflectance measurement method, the preferable reflectance is 13% or less in the entire wavelength range of 400 to 800 nm with respect to the ease of viewing the image on the display and the good color reproduction of the image when the conductive material is attached. More preferably, it is 10% or less.

  In the present invention, the plating treatment is performed after the development treatment for the purpose of imparting higher conductivity to the developed silver portion formed by the exposure and development treatment. In the present invention, the plating treatment is performed by electroless plating (chemical Reduction plating or displacement plating), electrolytic plating, or both electroless plating and electrolytic plating can be used.

  For the electroless plating in the present invention, known electroless plating techniques such as electroless nickel plating, electroless cobalt plating, electroless gold plating, and electroless silver plating can be used. Electroless copper plating is preferably performed to obtain the properties and light transmittance.

  The electroless copper plating solution in the present invention includes copper sources such as copper sulfate and copper chloride, reducing agents such as formalin, glyoxylic acid, potassium tetrahydroborate, dimethylamine borane, EDTA, diethylenetriaminepentaacetic acid, Rochelle salt, glycerol, meso -Erythritol, adenyl, D-mannitol, D-sorbitol, dulcitol, iminodiacetic acid, trans-1,2-cyclohexanediamine tetraacetic acid, 1,3-diaminopropan-2-ol tetraacetic acid, glycol ether diamine tetraacetic acid, tri Copper complexing agents such as isopropanolamine and triethanolamine, pH adjusting agents such as sodium hydroxide, potassium hydroxide and lithium hydroxide are contained. In addition, polyethylene glycol, yellow blood salt, bipyridyl, o-phenanthroline, neocuproine, thiourea, cyanide, and the like can be added as additives for improving bath stabilization and plating film smoothness. The plating solution is preferably aerated to increase stability.

  As described above, various complexing agents can be used in electroless copper plating. However, copper oxide is co-deposited depending on the type of complexing agent, greatly affecting conductivity, or with copper ions such as triethanolamine. It is known that a complexing agent having a low complex stability constant tends to precipitate copper, making it difficult to produce a stable plating solution or plating replenisher. Therefore, the complexing agents usually used industrially are limited, and in the present invention, the selection of the complexing agent is particularly important as the composition of the plating solution for the same reason. Particularly preferable complexing agents include EDTA and diethylenetriaminepentaacetic acid, which have a large stability constant of copper complex, and plating solutions using such a preferable complexing agent are, for example, high-temperature types used for the production of printed circuit boards. There is electroless copper plating. The method of high-temperature type electroless copper plating is described in detail in “Electroless plating basics and applications” (edited by Electroplating Research Group) p105 and the like. In high-temperature type plating, the treatment is usually performed at 60 to 70 ° C., and the treatment time varies depending on whether or not the electrolytic plating is performed after the electroless plating. Usually, the electroless plating treatment is performed for 1 to 30 minutes, preferably 3 to 20 minutes. By doing so, the object of the present invention can be achieved.

  When electroless plating treatment other than copper is performed in the present invention, for example, the method described in “Plating Technology Guidebook” (Tokyo Sheet Metal Cooperative Technical Committee, 1987) p406 to 432 can be used.

  In the present invention, electrolytic plating can be applied in addition to electroless plating. As electroplating, various plating methods such as copper plating, nickel plating, zinc plating, cadmium plating, tin plating, and alloy plating are known. It is preferable to use copper plating in order to ensure light transmission and conductivity at a low cost as with electroless plating. As a copper plating method, any of the known methods such as copper sulfate plating, copper borofluoride plating, copper cyanide plating, copper pyrophosphate plating, etc. can be used. However, copper sulfate plating, especially high-throw copper sulfate plating, is easy because of waste liquid. Is preferably used. Details of these electroplating methods are described in, for example, “Plating Technology Guidebook” (edited by the Technical Committee of Tokyo Sheet Metal Cooperative Association, 1987) p75-112.

  In the present invention, the metal silver portion can be activated with a solution containing palladium for the purpose of promoting electroless plating before the plating treatment. Palladium may be in the form of a divalent palladium salt or a complex salt thereof, or may be metallic palladium. However, it is preferable to use a palladium salt or a complex salt thereof in view of the stability of the liquid and the stability of the treatment.

  Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not limited to these examples.

  In order to obtain the conductive material in the present invention, a 100 μm thick polyethylene terephthalate film having a total light transmittance of 80% was used as the transparent support. On this transparent support, a backing layer having the following composition was applied and dried.

<Backing layer composition> ² g of gelatin per 1 m ²
Amorphous silica matting agent (average particle size 5μm) 20mg
Surfactant (S-1) 400mg
Dye 1 200mg

  Next, physical development nucleus layer coating solutions A-1 to A-11 containing palladium sulfide prepared as described below were applied to the surface of the transparent support having the backing layer opposite to the backing layer, respectively. , Dried.

<Preparation of palladium sulfide sol>
Liquid A Palladium chloride 5g
Hydrochloric acid 40ml
1000ml distilled water
B liquid sodium sulfide 8.6g
1000ml distilled water
Liquid A and liquid B were mixed with stirring, and 30 minutes later, the solution was passed through a column filled with an ion exchange resin to obtain palladium sulfide sol.

<Preparation of physical development nucleus layer coating solution><A-1> per 1 m ² each
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
Acryt UW-319SX (manufactured by Taisei Fine Chemical Co., Ltd.)
0.067g (solid content 0.02g)

<A-2>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
Acryt UW-319SX (manufactured by Taisei Fine Chemical Co., Ltd.)
0.100g (solid content 0.03g)

<A-3>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
Acryt UW-319SX (manufactured by Taisei Fine Chemical Co., Ltd.)
0.233 g (0.07 g of solid content)

<A-4>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
Acryt UW-319SX (manufactured by Taisei Fine Chemical Co., Ltd.)
0.267g (solid content 0.08g)

<A-5>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
ACRYT UW-223SX (manufactured by Taisei Fine Chemical Co., Ltd.)
0.17g (solid content 0.05g)

<A-6>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
ACRYT UW-550CS (manufactured by Taisei Fine Chemical Co., Ltd.)
0.17g (solid content 0.05g)

<A-7>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
Poliment SK-1000 (Nippon Shokubai Co., Ltd .; aminoethylated acrylic polymer)
0.13g (solid content 0.05g)

<A-8>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
EVAL E105B (Kuraray Co., Ltd .; ethylene-vinyl alcohol copolymer)
0.05g

<A-9>
The palladium sulfide sol 0.4mg
2 mass% glutaraldehyde aqueous solution 0.08ml
Surfactant (S-1) 4mg
Luck Star DS-203 (Dainippon Ink Chemical Co., Ltd .; carboxyl-modified SBR latex)
0.10 g (solid content 0.05 g)

<A-10>
The palladium sulfide sol 0.4mg
0.2% 2% Glyoxal solution
Surfactant (S-1) 4mg
10% lime-processed gelatin solution 0.5g

<A-11>
The palladium sulfide sol 0.4mg
0.2% 2% Glyoxal solution
Surfactant (S-1) 4mg

  Subsequently, an intermediate layer, a silver halide emulsion layer, and a protective layer having the following composition were coated on the physical development nucleus layer in order from the side closer to the support to obtain conductive material precursors 1-11. The silver halide emulsion was prepared by a general double jet mixing method for photographic silver halide emulsions. This silver halide emulsion was prepared with 95 mol% of silver chloride and 5 mol% of silver bromide, and an average grain size of 0.15 μm. The silver halide emulsion thus obtained was subjected to gold sulfur sensitization using sodium thiosulfate and chloroauric acid according to a conventional method. The silver halide emulsion thus obtained contains 0.5 g of gelatin per gram of silver.

<Intermediate layer composition> 0.5 g of gelatin per 1 m ²
Surfactant (S-1) 5mg
<Silver halide emulsion layer composition> 0.5 g of gelatin per 1 m ²
Silver halide emulsion 3g silver equivalent 1-phenyl-5-mercaptotetrazole 20mg
Surfactant (S-1) 20mg

<Protective layer composition> 1 g of gelatin per 1 m ²
Amorphous silica matting agent (average particle size 3.5μm) 15mg
Surfactant (S-1) 10mg

  The conductive material precursors 1 to 11 thus obtained were passed through a resin filter that cuts light of 400 nm or less with a contact printer using a mercury lamp as a light source, and a transparent original having a mesh pattern with a fine line width of 20 μm and a lattice spacing of 250 μm. Were exposed to light.

  The exposed conductive material precursors 1 to 11 were subjected to an immersion treatment at 20 ° C. for 60 seconds with an alkali treatment solution (silver complex diffusion transfer developer) having the following composition, followed by washing with water at 40 ° C. and drying. In this way, a conductive material having a silver thin film pattern was obtained.

<Alkali treatment liquid>
Potassium hydroxide 25g
Hydroquinone 18g
1-phenyl-3-pyrazolidone 2g
Potassium sulfite 80g
N-methylethanolamine 15g
Potassium bromide 1.2g
Total volume 1000ml with water
Adjust to pH = 12.2.

  The surface resistivity of the conductive material on which the mesh-like silver thin film pattern obtained as described above was formed was measured according to JIS K 7194 using a Lorester GP / ESP probe manufactured by Dia Instruments. The results are shown in Table 1.

  Next, the conductive material precursors 1 to 11 previously obtained were developed without being exposed to produce a conductive material in which a silver thin film was formed on the entire surface. Using a reflective UV-visible spectrophotometer (U-3500, manufactured by Hitachi, Ltd.), the surface of the conductive material opposite to the surface having the conductive layer across the support is used for the visible light region (400 Maximum reflectance at ˜800 nm) was measured. Note that magnesium oxide pellets were used as reference samples. The measurement results are shown in Table 1.

  Subsequently, electroless copper plating was applied to the conductive material on which the mesh-like silver thin film pattern was formed as follows. Treated with a cleaner 160 (Meltex degreasing solution) diluted to 5% by mass at 60 ° C. for 1 minute, washed with water, then plated with Cu 5100 (Meltex plating solution) at 50 ° C. for 12 minutes, washed with water and dried. Went. The surface resistivity of the copper plating pattern thus obtained was measured by the same method as described above. Furthermore, an adhesive tape (Livic Tape No. 401 manufactured by Nitto Denko Corporation) was affixed to the mesh surface, peeled off vigorously, and the peeling state of the mesh pattern was visually observed. The degree of peeling was evaluated in four stages, with no peeling indicated as “◯”, very slight peeling as “◯ Δ”, about half peeling as “Δ”, and whole peeling as “x”. The results are shown in Table 1.

  In addition, the adhesion between the functional layer (ultraviolet absorption layer) and the conductive material was evaluated. An ultraviolet absorber (Halth Hybrid UV-G101 manufactured by Nippon Shokubai Co., Ltd.) was applied to the pattern forming surface of the conductive material obtained by electroless plating the mesh pattern silver thin film described above using a # 8 wire bar. The solvent was removed by drying at 0 ° C. for 2 minutes to obtain a conductive material having an ultraviolet absorbing layer having a thickness of 3 μm. In order to confirm the adhesion between the ultraviolet absorbing layer and the conductive material, 100 square cuts reaching the support through the ultraviolet absorbing layer were removed by using a cutter guide with a gap distance of 2 mm. Put on. Next, a cellophane adhesive tape (No. 405 manufactured by Nichiban Co., Ltd., width of 24 mm) is attached to the cut surface of the grid, and is completely adhered by rubbing with an eraser. Thereafter, the cellophane pressure-sensitive adhesive tape is peeled off vertically from the surface of the ultraviolet absorbing layer, and the number of squares from which the ultraviolet absorbing layer is peeled off from the conductive material is visually counted. -50 masses were marked as Δ, 51-70 squares as Δx, and 71 cells or more as x. The results are shown in Table 1.

  From the results of Table 1, the conductive material using the amino group-containing latex of the present invention for the physical development nucleus layer has a low surface resistivity, excellent adhesion between the plating and the support, and from the support side. It can be seen that the seen silver has low visible light reflectance, excellent visibility, and good adhesion to the functional layer.

Claims (2)

  A conductive material precursor having at least a physical development nucleus layer and a silver halide emulsion layer in this order on a transparent support, wherein the physical development nucleus layer contains an amino group-containing latex. .   The electroconductive material manufactured using the electroconductive material precursor of Claim 1.