JP2009081244A - Method of manufacturing conductive pattern sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a high-definition conductive pattern sheet having sufficient electric conductivity, and improved in adhesiveness between a conductive pattern and a base material. <P>SOLUTION: The method of manufacturing a conductive pattern sheet is characterized in that a layer containing a photocatalytically-active material is formed on the base material; a solution containing a metal compound is arranged on the layer; and a metal pattern used as wiring is formed by subjecting the metal in the metal compound to photoreduction by an exposure process. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a conductive pattern sheet in which a metal pattern to be a wiring is formed by photoreduction in the presence of a photocatalytically active material.

  Conventionally, to produce an electronic circuit or the like having a fine conductive pattern, a resist layer is laminated on a substrate on which a conductive layer is formed, irradiated with light through a photomask having a desired pattern, and then developed. Thereafter, a photolithographic method for removing an unnecessary resist layer has been performed. However, this photolithographic method is troublesome because it requires a large number of steps, and there is also a problem in terms of cost. Further, the disposal of the removed resist layer has a problem in that it has a burden on the environment.

  In order to solve such a problem, a method has been proposed in which a conductive pattern is formed by directly injecting conductive ink onto a substrate surface using a printing apparatus such as an ink jet apparatus. For example, a conductive circuit forming pattern made of a photopolymerization initiator-containing inkjet ink is provided on a predetermined portion of the substrate surface, and an ultraviolet curable conductive ink layer that does not contain a photopolymerization initiator is provided on the pattern, and ultraviolet rays are emitted. It is intended to improve the adhesion between the substrate and the ink by irradiating and curing the ultraviolet curable conductive ink layer corresponding to the pattern (see, for example, Patent Document 1).

  As another example, after a non-conductive groove structure is formed on a substrate, an electroless plating catalyst-containing solution is patterned in the groove on the substrate by an inkjet method, and further followed by an electroless plating method or an electroless plating method. An attempt is made to improve the accuracy of the conductive pattern by depositing a conductive substance in the opening of the groove structure by electrolytic plating (see, for example, Patent Document 2).

As a result of intensive investigation of the above technique, the inventor has improved the adhesion with the substrate in the method proposed in Patent Document 1, but the ultraviolet curable resin contained in the ink remains in the wiring. However, there is a problem that the resistance value does not decrease sufficiently. In addition, although the method proposed in Patent Document 2 improves the accuracy of the conductive pattern, it is not suitable for high resolution due to a non-conductive groove structure that is essentially unnecessary for wiring. There was a problem of poor adhesion to the substrate.
JP 2004-152805 A JP 2005-50969 A

  The present invention has been made in view of the above problems, and the object thereof is a conductive pattern sheet having sufficient electrical conductivity, high definition, and improved adhesion between the conductive pattern and the substrate. It is to provide a manufacturing method.

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

  1. A layer containing a photocatalytically active material is provided on a substrate, a solution containing a metal compound is disposed on the layer, and a metal pattern serving as a wiring is formed by photoreducing the metal in the metal compound by an exposure process. A process for producing a conductive pattern sheet characterized by the above.

  2. 2. The method for producing a conductive pattern sheet according to 1 above, wherein the solution containing the metal compound is disposed by ink jet recording in which an ink jet recording apparatus performs injection drawing.

  3. 4. The method for producing a conductive pattern sheet according to 3 above, wherein the inkjet recording is a method using a pressure applying unit and an electric field applying unit.

  4). 2. The method for producing a conductive pattern sheet according to 1 above, wherein the solution containing the metal compound is disposed on the entire surface of the layer containing the photocatalytic active material.

  5). 5. The conductive pattern sheet according to any one of 1 to 4, wherein the metal in the solution containing the metal compound is at least one selected from copper, silver, gold, nickel, palladium, and zinc. Manufacturing method.

  6). 6. The method for producing a conductive pattern sheet according to any one of 1 to 5, further comprising an electroless plating treatment step or an electrolytic plating treatment step after the exposure step.

  7. The method for producing a conductive pattern sheet according to any one of the above items 1 to 6, further comprising a step of washing a layer containing a photocatalytically active material after the exposure step.

  8). The method for producing a conductive pattern sheet according to any one of 1 to 7, wherein the photocatalytically active material is titanium dioxide.

  According to the present invention, it was possible to provide a method for producing a conductive pattern sheet having sufficient electrical conductivity, high definition, and improved adhesion between the conductive pattern and the substrate.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

  In the method for producing a conductive pattern sheet of the present invention, a layer containing a photocatalytically active material is provided on a substrate, a solution containing a metal compound is disposed on the layer, and the metal in the metal compound is photoreduced by an exposure step. And forming a metal pattern for forming the wiring.

〔Base material〕
Examples of the substrate used in the present invention include resin films such as polyimide films, polyamideimide films, polyamide films, and polyester films, glass-epoxy substrates, silicon substrates, ceramic substrates, and glass substrates.

  The material of the resin film used in the present invention is not particularly limited. For example, polyester film (polyethylene terephthalate, polyethylene naphthalate, etc.), polycarbonate film, polyarylate film, polysulfone (including polyethersulfone). Film, polyethylene film, polypropylene film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol film, syndiotactic polystyrene film, polycarbonate film, cycloolefin polymer film (Arton (manufactured by JSR), Zeonex, Zeonea (and above) , Manufactured by Nippon Zeon)), polyethersulfone film, polysulfone film, polymethylpentene film, poly Chromatography ether ketone film, polyether ketone imide film, a polyamide film, a fluororesin film, a nylon film, polymethyl methacrylate film, polyacrylate films, and polyarylate films. The film which laminated | stacked the film of the different material which has these materials as a main component may be sufficient.

  In the present invention, from the viewpoint of enhancing the adhesion between the base material and the layer containing the photocatalytically active material provided thereon, the surface of the base material is pretreated with corona discharge treatment, flame treatment, ozone treatment, primer treatment, It is preferable to perform desmear treatment, ultraviolet treatment, radiation treatment, surface roughening treatment, chemical treatment including silane coupling agent, acid, alkali, surfactant and the like.

  Examples of the mechanism for improving the adhesion include cleaning of the surface by removing foreign substances adhering to the surface that inhibits adhesion, using an anchor effect due to unevenness of the member interface, and inserting an adhesive compound at the interface with both members. . The binder contained in the layer containing the photocatalytically active material is preferably selected in advance from a compound having good adhesion between the substrate and the binder. For example, a polyester-based substrate includes a polyurethane-based binder, a polyimide-based substrate, and a glass fiber kneaded epoxy-based substrate includes a polyacrylic binder and a polyepoxy-based binder.

[Layer containing photocatalytically active material]
The layer containing the photocatalytically active material according to the present invention is composed of a compound containing the photocatalytically active material. The photocatalytically active material in the present invention refers to a material having a function of reducing surrounding substances by irradiating light, and the layer together with the photocatalytically active material, if necessary, a polymer binder for the purpose of increasing the strength of the layer You may have. The binder is interposed between the substrate and the photocatalytically active material to give physical strength, relaxes the stress generated during metal formation, and improves the adhesion between the substrate and the layer containing the photocatalytically active material Etc.

  A preferred form of the layer containing the photocatalytically active material according to the present invention is a porous shape.

Examples of the photocatalytically active material according to the present invention include oxides and sulfides such as titanium dioxide, zinc oxide, SrTiO ₃ , Ag—NbO ₂ F, CdS, and ZnS. The photocatalytically active material according to the present invention is preferably titanium dioxide.

(binder)
As the binder according to the present invention, a known polymer compound can be used as long as it can bind a substrate, a metal oxide, a metal film and the like. Preferred binders include proteins such as gelatin and gelatin derivatives, or cellulose derivatives, natural compounds such as polysaccharides such as starch, gum arabic, dextran, pullulan and carrageenan, polyvinyl alcohol, polyvinyl pyrrolidone, acrylamide polymers, Examples thereof include synthetic polymer compounds such as derivatives thereof.

  Examples of gelatin derivatives include acetylated gelatin, phthalated gelatin, polyvinyl alcohol derivatives include terminal alkyl group-modified polyvinyl alcohol, terminal mercapto group-modified polyvinyl alcohol, and cellulose derivatives include hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, and the like. It is done.

Further, research disclosures and those described in JP-A No. 64-13546, pages 71 to 75, U.S. Pat. No. 4,960,681, JP-A No. 62-245260, etc. water-absorbing polymer, i.e. -COOM or -SO ₃ M (M is a hydrogen atom or an alkali metal) homopolymer or a vinyl monomer together or with other vinyl monomers of the vinyl monomer having a (e.g., sodium methacrylate, ammonium methacrylate, Copolymers with potassium acrylate etc.) are also used. Two or more of these binders can be used in combination.

  These binders may be cured. Examples of hardeners include, for example, U.S. Pat. Nos. 4,678,739 and 4,791,042, JP-A-59-116655, 62-245261 and 61-18942. Nos. 61-249054, 61-245153, JP-A-4-218044, and the like.

  More specifically, aldehyde hardeners (formaldehyde, etc.), aziridine hardeners, epoxy hardeners, vinyl sulfone hardeners (N, N'-ethylene-bis (vinylsulfonylacetamide) Ethane etc.), N-methylol hardeners (dimethylolurea etc.), boric acid, metaboric acid or polymer hardeners (compounds described in JP-A-62-234157). When gelatin is used as the aqueous compound, it is preferable to use a vinyl sulfone type hardener or a chlorotriazine type hardener alone or in combination. Moreover, when using polyvinyl alcohol, it is preferable to use boron-containing compounds such as boric acid and metaboric acid.

  These hardeners are used in an amount of 0.001 to 1 g, preferably 0.005 to 0.5 g, per 1 g of the aqueous compound. In order to increase the film strength, it is also possible to adjust the humidity during heat treatment or curing reaction.

  Polymers dispersed in aqueous solvents include natural rubber latex, styrene butadiene rubber, butadiene rubber, nitrile rubber, chloroprene rubber, isoprene rubber and other latexes, polyisocyanate, epoxy, acrylic, silicone, polyurethane, Examples thereof include a thermosetting resin and a photocurable resin in which urea, phenol, formaldehyde, epoxy-polyamide, melamine, alkyd resin, vinyl resin and the like are dispersed in an aqueous solvent. Of these polymers, it is preferable to use an aqueous polyurethane resin described in JP-A-10-76621.

[Solution containing metal compound]
The solution containing the metal compound according to the present invention may have any composition as long as it is a solution containing metal ions, metal fine particles, metal complexes and the like. Examples of the metal species that are preferably used include copper, silver, gold, nickel, palladium, zinc, and mixtures thereof.

  When the solution containing the metal compound according to the present invention is used as an ink for inkjet recording, a water-soluble organic solvent can be used for the ink. Examples of water-soluble organic solvents include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol, pentanol, hexanol, cyclohexanol, benzyl alcohol, etc.), polyhydric alcohols (For example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol, etc.), polyhydric alcohol ether (E.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, Tylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol mono Butyl ether, ethylene glycol monophenyl ether, propylene glycol monophenyl ether, etc.), amines (for example, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine) , Ethylenediamine, diethylenediamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine, etc.), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, etc.) ), Heterocyclic rings (for example, 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone), sulfoxides (for example, dimethyl sulfoxide) , Sulfones (for example, sulfolane), urea, acetonitrile, acetone and the like.

  In addition to the ink, various other known additives such as a viscosity adjusting agent may be used depending on the purpose of improving ejection stability, compatibility with print heads and ink cartridges, storage stability, image storage stability, and other various performances. , Surface tension adjusting agent, specific resistance adjusting agent, film forming agent, dispersing agent, surfactant, ultraviolet absorber, antioxidant, fading inhibitor, antifungal agent, rust inhibitor, etc. it can.

  Specifically, polystyrene, polyacrylic acid esters, polymethacrylic acid esters, polyacrylamides, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, or a copolymer thereof, urea resin, melamine resin, etc. Oil latex fine particles such as organic latex, liquid paraffin, dioctyl phthalate, tricresyl phosphate, silicone oil, various cationic or nonionic surfactants, JP-A-57-74193, 57-87988 and 62-261476 UV absorbers described in each of JP-A-57-74192, JP-A-57-87989, JP-A-60-72785, JP-A-61465991, JP-A-1-95091 and JP-A-3-13376. Japanese Patent Laid-Open Publication No. 59-4 No. 993, No. 59-52689, No. 62-280069, No. 61-242871, and JP-A-4-219266, etc., optical brighteners, sulfuric acid, phosphoric acid, citric acid, water Examples thereof include pH adjusters such as sodium oxide, potassium hydroxide and potassium carbonate.

  There is no particular limitation on the preparation of the ink, but when preparing an ink containing various additives, it is preferable to prepare the ink so that aggregation and sedimentation do not occur during the preparation process. If necessary, it is possible to adopt a blending method such as adjusting the order of addition of additives and the rate of addition.

  Although there is no restriction | limiting in particular in the viscosity of an ink, It is preferable that the viscosity in 25 degreeC is 2 mPa * s or more and 10 mPa * s or less. Further, it is preferable that the viscosity of the ink does not depend on the share rate.

  In the ink, the surface tension is preferably 40 mN / m or less, more preferably 25 to 35 mN / m. The surface tension (mN / m) of the ink referred to in the present invention is a value obtained by measuring the surface tension measured at 25 ° C., and its measuring method is described in general interface chemistry and colloid chemistry reference books. , New Experimental Chemistry Lecture Volume 18 (Interface and Colloid), The Chemical Society of Japan, Maruzen Co., Ltd. 68-117 can be referred to.

  From the viewpoint of ink storage stability, the electrical conductivity is preferably 1 mS / m or more and 500 mS / m or less, more preferably 1 mS / m or more and 200 mS / m or less, and still more preferably 10 mS / m. As mentioned above, it is 100 mS / m or less. In preparing the ink, it is preferable to appropriately adjust the ion concentration.

[Method of arranging solution containing metal compound]
The arrangement of the solution containing the metal compound according to the present invention on the layer containing the photocatalytic active material may be arranged on the entire surface of the layer or in a desired pattern.

  As a placement method, a dip coating method, a spray coating method, a spray method using a vapor phase as a spray method using a vibration of a piezoelectric element, for example, a piezo ink jet head or a thermal method using bumping Examples include a bubble jet (registered trademark) ink jet head that causes droplets to fly using a head, and a spray method that sprays liquid by air pressure or liquid pressure.

  Examples of the printing method include screen printing, flexographic printing, letterpress printing and intaglio printing. The coating method can be appropriately selected from known coating methods. For example, an air doctor coater, blade coater, rod coater, knife coater, squeeze coater, impregnation coater, reverse roller coater, transfer roller coater, curtain coater, double roller Examples include a coater, a slide hopper coater, a gravure coater, a kiss roll coater, a bead coater, a cast coater, a spray coater, a calendar coater, and an extrusion coater.

  In the present invention, since it is preferable that a solution containing a metal compound can be arranged with a line width equal to or less than the line width of the light irradiation pattern in the exposure step, ink jet recording using these ink jet recording apparatuses is preferable. From the viewpoint that a thin line having a line width of 20 μm or less used in an electric circuit or the like can be formed with high accuracy, the method for discharging the conductive ink by the ink jet recording apparatus is a method using pressure applying means and electric field applying means. Is preferred.

  Hereinafter, ink jet recording using a pressure applying unit and an electric field applying unit will be described.

  In general, in order to draw a fine line width pattern required in an electronic circuit or the like with high definition, it is necessary to further refine the ink droplets ejected from the ink jet recording apparatus. However, electro-mechanical conversion methods (eg, single cavity type, double cavity type, bender type, piston type, shear mode type, shared wall type, etc.) and electro-thermal conversion methods (eg, thermal ink jet type, bubble jet type) When a very small ink droplet is ejected using only (registered trademark type) output means, the kinetic energy imparted to the ink droplet ejected from the nozzle is proportional to the cube of the radius of the ink droplet Therefore, the microdroplet cannot secure sufficient kinetic energy enough to withstand air resistance, and is subject to disturbance due to air convection, making accurate landing difficult.

  Furthermore, since the effect of surface tension increases as the ink droplets become finer, the vapor pressure of the droplets increases and the amount of evaporation increases. For this reason, fine droplets cause a significant loss of mass during flight, and there is a problem that it is difficult to maintain the shape of the droplets upon landing. As described above, increasing the accuracy of the landing position is a problem that contradicts the miniaturization of ink droplets, and there is an obstacle to realizing these two simultaneously.

  In the present invention, it is preferable to apply an injection method using a pressure applying means and an electric field applying means as a method for solving the above problems.

  This ejection method uses a nozzle having an ejection port with an inner diameter of 0.1 to 100 μm, applies an arbitrary waveform voltage to the conductive ink, and charges the conductive ink to discharge the ink droplets. This is a method of discharging from an outlet to a substrate having a resin layer. That is, in this ejection method, the inner diameter of the nozzle outlet is 0.1 to 100 μm and the electric field strength distribution is narrow, so by applying an arbitrary waveform voltage to the conductive ink supplied into the nozzle. The electric field can be concentrated.

  As a result, the formed ink droplets can be made minute and the shape can be stabilized. Therefore, it is possible to form an ink droplet pattern composed of a plurality of ink droplets, for example, less than 1 pl (picoliter), on the surface of the resin layer. In addition, since the electric field strength distribution is narrow, the total applied voltage applied to the conductive ink in the nozzle can be reduced.

  Further, immediately after the ink droplet is ejected from the nozzle, the ink droplet is accelerated by an electrostatic force acting between the electric field and the electric charge. However, the ink droplets that are fine droplets and the electric field is concentrated are accelerated by the mirror image force as they approach the resin layer. By balancing the deceleration by the air resistance and the acceleration by the mirror image force, it is possible to stably fly the fine droplets and improve the landing accuracy.

  FIG. 1 is a schematic cross-sectional view showing an example of an ink jet recording apparatus including a pressure applying unit and an electric field applying unit that can be preferably applied to the present invention.

  In FIG. 1, an ink jet recording apparatus 20 has an ultrafine nozzle 21 that discharges droplets of electrically conductive ink that can be charged from a tip portion toward a substrate K having a resin layer, and is opposed to the tip portion of the nozzle 21. A counter electrode 23 that is disposed on the surface to support the substrate K on its opposite surface, a conductive ink supply unit that supplies conductive ink to the flow path 22 in the nozzle 21, and a conductive ink in the nozzle 21. And an ejection voltage application means (voltage application means) 25 for applying an ejection voltage having an arbitrary waveform. The nozzle 21 and a part of the conductive ink supply unit and a part of the discharge voltage application unit 25 are formed integrally with the nozzle plate 26.

  The nozzle 21 is suspended from the lower surface layer 26c of the nozzle plate 26, and is formed integrally with the lower surface layer 26c. The tip of the nozzle 21 is directed to the counter electrode 23. Inside the nozzle 21, an in-nozzle flow path 22 is formed that penetrates from the tip portion along the center line.

  The nozzle 21 is formed with an ultrafine diameter using, for example, an electrical insulator such as glass. Specific examples of the dimensions of each part of the nozzle 21 are as follows: the inner diameter of the nozzle flow path 22 is 1 μm, the outer diameter at the tip of the nozzle 21 is 2 μm, the root of the nozzle 21, that is, the diameter of the upper end is 5 μm, The height of 21 is set to 100 μm. Moreover, the shape of the nozzle 21 is formed in a truncated cone shape close to a conical shape. The nozzle 21 as a whole is formed of an insulating resin material together with the lower surface layer 26 c of the nozzle plate 26.

  Each dimension of the nozzle 21 is not limited to the above example. In particular, the inner diameter of the ejection port is a range in which the ejection voltage that enables ejection of droplets due to the effect of electric field concentration is less than 1000 V, for example, 100 μm or less, more preferably 20 μm or less, An inner diameter, for example, 0.1 μm, in a range where it is feasible to form a through hole through which a solution is passed by the current nozzle forming technique is set as the lower limit.

  The conductive ink supply means is provided inside the nozzle plate 26 at a position that is the root of the nozzle 21 and communicates with the flow path 22 in the nozzle, and an ink chamber from an external conductive ink tank (not shown). A supply path 27 that guides conductive ink to 24 and a supply pump (not shown) that applies supply pressure of the solution to the ink chamber 24 are provided.

  The supply pump supplies conductive ink to the tip of the nozzle 21 and supplies the conductive ink while maintaining a supply pressure in a range that does not spill from the tip.

  The discharge voltage application means 25 applies a discharge voltage to the conductive ink in the nozzle 21 to charge the conductive ink, thereby causing the droplets of the conductive ink to move from the discharge port of the nozzle 21 toward the substrate K. To be discharged. The discharge voltage application means 25 is provided inside the nozzle plate 26 and at a boundary position between the ink chamber 24 and the nozzle flow path 22, and the discharge voltage application discharge electrode 28 is always on the discharge electrode 28. A bias power source 30 that applies a DC bias voltage and an ejection voltage power source 29 that applies a pulse voltage that is superimposed on the bias voltage to a potential required for ejection on the ejection electrode 28 are provided.

  The discharge electrode 28 directly contacts the conductive ink inside the ink chamber 24 to charge the conductive ink and apply a discharge voltage.

  The bias voltage from the bias power supply 30 is always applied within a range in which conductive ink is not discharged, thereby reducing the width of the voltage to be applied at the time of discharge, thereby improving the reactivity at the time of discharge. I am trying. As an example, the bias voltage is applied at 300V DC and the pulse voltage is marked at 100V. Therefore, the superimposed voltage at the time of ejection is 400V.

  The nozzle plate 26 includes an upper surface layer 26a positioned at the uppermost layer, a flow path layer 26b forming a conductive ink supply path positioned therebelow, and a lower surface layer 26c formed further below the flow path layer 26b. The discharge electrode 28 is interposed between the flow path layer 26b and the lower surface layer 26c.

  The counter electrode 23 has a counter surface perpendicular to the nozzle 21 and supports the substrate K along the counter surface. The distance from the tip of the nozzle 21 to the facing surface of the counter electrode 23 is kept constant, for example, 100 μm.

  Further, since the counter electrode 23 is grounded, the ground potential is always maintained. Accordingly, when a pulse voltage is applied, the liquid droplets ejected by the electrostatic force generated by the electric field generated between the tip of the nozzle 21 and the opposing surface are guided to the opposing electrode 23 side.

  The ink jet recording apparatus 20 discharges liquid droplets by increasing the electric field strength by concentrating the electric field at the tip of the nozzle 21 by making the nozzle 21 ultrafine, so that even if there is no induction by the counter electrode 23, the liquid is discharged. Although it is possible to discharge droplets, it is desirable that induction by electrostatic force is performed between the nozzle 21 and the counter electrode 23. In this case, the droplet discharged from the nozzle 21 and decelerated by air resistance can be accelerated by the mirror image force. Therefore, by balancing the deceleration by the air resistance and the acceleration by the mirror image force, it is possible to stably fly the fine droplets and improve the landing accuracy. Furthermore, the charge of the charged droplets can be released by grounding the counter electrode 23.

  The ink jet recording apparatus 20 as described above may be a scanning ink jet recording apparatus that can be scanned in a direction orthogonal to the conveyance direction of the base material K by a driving mechanism (not shown). In this case, a plurality of nozzles 21 may be arranged in the ink jet recording apparatus 20. The ink jet recording apparatus 20 may be a line type ink jet recording apparatus in which a large number of nozzles 21 are arranged in a direction orthogonal to the transport direction of the substrate K.

[Exposure process]
The exposure step according to the present invention refers to a step of activating the photocatalytically active material contained in the layer containing the photocatalytically active material and reducing the metal in the surrounding metal compound.

  By irradiating the patterned light in the exposure process, only the metal in the light-irradiated region is selectively reduced, and a metal pattern is formed in the layer containing the photocatalytically active material or on the layer containing the photocatalytically active material. Therefore, a conductive pattern with high definition and high adhesion can be produced. In the exposure step, the entire surface of the substrate may be irradiated, or the wiring pattern may be irradiated.

  As a method for exposing a wiring pattern, a quartz glass substrate on which a metal pattern such as chromium is arranged is brought into close contact with a layer containing a photocatalytically active material, or reduction projection is performed using a lens or a mirror. And a method of direct drawing with an electron beam or the like.

  The light source may be either visible light or ultraviolet light, but ultraviolet light is preferable from the viewpoint of sufficiently activating the photocatalytically active material.

  The light irradiation in the exposure step is performed after the solution containing the metal compound is arranged in the layer containing the photocatalytic active material, even if the light irradiation is performed at the same timing when the solution containing the metal compound is arranged in the layer containing the photocatalytic active material. Light irradiation may be performed.

[Electroless plating process or electrolytic plating process]
In the present invention, an electroless plating process or an electrolytic plating process may be performed for the purpose of improving the conductivity of the metal pattern and adjusting the line width and film thickness.

  Hereinafter, a plating method applicable to the present invention will be described.

  In the present invention, a conventionally known plating method can be applied. Among them, an electroless plating method is applied from the viewpoint that a low-resistance conductive pattern can be easily and inexpensively plated without complicated steps. It is preferable.

  The plating process by the electroless plating method is a method in which a plating agent is brought into contact with a conductive pattern containing metal fine particles that act as a plating catalyst according to the above-described method. Thereby, the metal fine particle which is a plating catalyst and a plating agent contact, electroless plating is given to a conductive pattern part, and more excellent electroconductivity can be obtained.

  As a plating agent that can be used in the plating treatment according to the present invention, for example, a solution in which metal ions to be deposited as a plating material are uniformly dissolved is used, and a reducing agent is contained together with a metal salt. Here, a solution is usually used, but not limited to this as long as it causes electroless plating, and a gaseous or powder plating agent can also be applied.

  Specifically, as this metal salt, a halide, nitrate, sulfate, phosphate, borate, acetate of at least one metal selected from Au, Ag, Cu, Ni, Co, Fe, Tartrate, citrate, etc. are applicable. As the reducing agent, hydrazine, hydrazine salt, borohalide salt, hypophosphite, hyposulfite, alcohol, aldehyde, carboxylic acid, carboxylate, and the like are applicable. In addition, you may contain in the electrode which elements, such as boron, phosphorus, and nitrogen contained in these reducing agents, precipitate. Alternatively, an alloy may be formed using a mixture of these metal salts.

  As the plating agent, a mixture of the metal salt and the reducing agent may be applied, or the metal salt and the reducing agent may be applied separately. Here, in order to form a conductive pattern more clearly, it is preferable to apply a mixture of a metal salt and a reducing agent. Further, when the metal salt and the reducing agent are applied separately, a more stable conductive pattern can be formed by arranging the metal salt first in the conductive pattern portion and then arranging the reducing agent.

  If necessary, the plating agent may contain additives such as a buffer for adjusting pH and a surfactant. Moreover, as a solvent used for the solution, an organic solvent such as alcohol, ketone, ester or the like may be added in addition to water.

  The composition of the plating agent is composed of a metal salt of the metal to be deposited, a reducing agent, and, if necessary, an additive and an organic solvent, but the concentration and composition can be adjusted according to the deposition rate. . Further, the deposition rate can be adjusted by adjusting the temperature of the plating agent. Examples of the method for adjusting the temperature include a method for adjusting the temperature of the plating agent, and a method for adjusting the temperature by heating and cooling the substrate before the immersion, for example, when immersed in the plating agent. Furthermore, the film thickness of the metal thin film deposited by the time immersed in a plating agent can also be adjusted.

[Step of washing layer containing photocatalytically active material]
In the present invention, after the metal pattern is formed by the exposure process, the layer containing the photocatalytically active material or the layer containing the photocatalytically active material is washed for the purpose of improving conductivity and removing unnecessary metal compounds. You may perform a process. Examples of the substance removed by the washing step include a binder of a layer containing a photocatalytically active material, a photocatalytically active material, a metal compound, and the like.

  The conductive pattern sheet according to the present invention has a simple structure and is inexpensive, and is used as an information recording medium such as a contact type, non-contact type or hybrid type IC card, IC label, IC tag, IC form, paper computer, etc. It can be used as a general conductive circuit such as a printed circuit board. Moreover, it can also be used as an electromagnetic wave shielding film, using a transparent film as a base material.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
[Preparation of a sample having a conductive pattern]
<< Preparation of Sample 1 >>
(Preparation of ink 1)
Ink 1 was prepared by dispersing silver chloride and palladium chloride in a mixed solution of water / ethylene glycol = 1/3 at 45 mmol / L and 5 mmol / L, respectively.

(Electroless copper plating solution)
Copper sulfate 0.04 mol Formaldehyde (37% by mass) 0.08 mol Sodium hydroxide 0.10 mol Triethanolamine 0.05 mol Polyethylene glycol 100 ppm
Add water to bring the total volume to 1L.

(Formation of conductive pattern)
After the ink 1 prepared above was ejected in a line and space of 5 to 100 μm by an ink jet method onto a commercially available glass-epoxy substrate having a surface subjected to a corona discharge treatment of 12 W · min / m ² for 2 seconds, the ink 1 The solvent was dried. Next, it is immersed in the above electroless copper plating bath and subjected to electroless plating treatment at 75 ° C. for 20 minutes, and a conductive pattern having a plurality of types of wirings having an average film thickness of 4.5 μm and different line and space (see FIG. 2) was formed and this was designated as Sample 1.

<< Preparation of Sample 2 >>
In the preparation of Sample 1, Sample 2 was prepared in the same manner except that the ink 1 was replaced with the following ink 2 and the electroless copper plating treatment was not performed.

(Preparation of ink 2)
Mixing 44 parts by mass of trimethylolpropane triacrylate (TMPTA), 36 parts by mass of 2-hydroxyethyl methacrylate (HEMA), and 7 parts by mass of rosin oligomer <trade name: Beamset 102 (manufactured by Arakawa Chemical Industries)> To do. Ink 2 was prepared by adding 13 parts by mass of silver powder as a conductive substance.

<< Preparation of Sample 3 >>
(Preparation of a layer containing a photocatalytically active material)
On a commercially available glass-epoxy substrate having a surface subjected to a corona discharge treatment of 12 W · min / m ² for 2 seconds, 10% of titanium dioxide ST-01 (average particle diameter 7 nm) manufactured by Ishihara Sangyo Co., Ltd., Kuraray polyvinyl alcohol PVA- An aqueous solution containing 3% of 235 was applied to a dry film thickness of 0.8 μm and dried to prepare a layer containing a porous photocatalytically active material.

(Formation of conductive pattern)
On the layer containing the photocatalytically active material while irradiating ultraviolet rays from the back surface of the glass-epoxy substrate having the layer containing the photocatalytically active material through a Cr / quartz glass mask having a wiring pattern of 5 to 100 μm of line and space. After the ink 1 in the sample 1 was ejected according to the ultraviolet irradiation pattern by the inkjet method, the solvent of the ink 1 was dried.

  Next, the sample 1 is immersed in an electroless copper plating bath and subjected to an electroless plating process at 75 ° C. for 20 minutes to have a plurality of types of wirings having an average film thickness of 4.5 μm and different lines and spaces. A pattern was formed and this was designated as Sample 3.

<< Preparation of Sample 4 >>
In Sample 3, Sample 4 was prepared in the same manner except that a step of ultrasonically cleaning the entire sample in 60 ° C. warm water for 5 minutes was interposed between the step of drying the ink solvent and the electroless copper plating step. .

<< Preparation of Sample 5 >>
A sample 5 was prepared in the same manner as the sample 3 except that the ink application was changed to the application by the ink jet recording apparatus provided with the pressure application unit and the electric field application unit shown in FIG.

<< Preparation of Sample 6 >>
A sample 6 was prepared in the same manner as the sample 4 except that the ink application was changed to the application by the ink jet recording apparatus provided with the pressure application means and the electric field application means shown in FIG.

<< Preparation of Sample 7 >>
(Preparation of ink 3)
Ink 3 was prepared by dispersing copper sulfate in a mixed solution of water / ethylene glycol = 1/3 at 50 mmol / L.

  Sample 7 was prepared in the same manner as in sample 5, except that ink 1 was changed to ink 3 and the electroless copper plating step was omitted.

<< Preparation of Sample 8 >>
Sample 8 was prepared in the same manner except that ink 1 was changed to ink 3 in sample 5.

<< Preparation of Sample 9 >>
Sample 9 was prepared in the same manner as in Sample 8, except that a step of ultrasonically cleaning the entire sample in 60 ° C. warm water for 5 minutes was interposed between the step of drying the ink solvent and the electroless copper plating step. .

<< Preparation of Sample 10 >>
Sample 10 was prepared in the same manner as in Sample 7, except that the ink arrangement method was changed to the silk screen method.

<< Preparation of Sample 11 >>
Sample 11 was prepared in the same manner as in Sample 7, except that the titanium dioxide in the layer containing the photocatalytically active material was changed to zinc oxide.

<< Preparation of Sample 12 >>
Sample 12 was prepared in the same manner as in Sample 7, except that the layer containing the photocatalytically active material was changed to SrTiO ₃ .

<< Preparation of Sample 13 >>
Cr / quartz having a wiring pattern of 5 to 100 [mu] m in line and space from the back side by applying ink 1 to the glass-epoxy substrate side having a layer containing the photocatalytically active material prepared in Sample 3 by dipping. Ultraviolet rays were irradiated through a glass mask. The obtained sample was ultrasonically cleaned in an ethanol solvent for 5 minutes to wash out unnecessary ink.

  Next, the sample 1 is immersed in an electroless copper plating bath and subjected to an electroless plating process at 75 ° C. for 20 minutes to have a plurality of types of wirings having an average film thickness of 4.5 μm and different lines and spaces. A pattern was formed and this was designated as Sample 13.

[Evaluation]
(Adhesion)
After the cellophane tape (CT24, manufactured by Nichiban Co., Ltd.) is adhered to the sample surface with the finger pad, the cellophane tape is peeled off at once, and the area ratio of the peeled conductive pattern is obtained. Sex was evaluated.

A: No peeling of conductive pattern (equivalent to test result classification 0)
○: Peeling area of the conductive pattern is greater than 0% and 1.0% or less Δ: Peeling area of the conductive pattern is greater than 1.0% and 5.0% or less ×: Peeling area of the conductive pattern is 5 Greater than 0.0%.

(Fine line reproducibility)
The surface of the sample was observed with a KEYENCE microscope VHX-600, and fine line reproducibility was evaluated according to the following criteria.

◎: Line width and line spacing are reproduced with accuracy within ± 10% ○: Line width and line spacing are reproduced with accuracy within ± 20% △: Line width and line spacing are ± Reproduced with an accuracy of 50% or less. X: The reproduction accuracy of the line width and the line interval exceeds ± 50%.

(Conductivity)
The line resistivity of the wiring corresponding to 100 μm of line and space was obtained and evaluated as conductivity.

  The evaluation results of each sample are shown in Table 1. In Table 1, the IJ method represents an ink jet method, the SIJ method represents an ink jet method including a pressure applying unit and an electric field applying unit, and silk represents a silk screen method.

  From Table 1, it can be seen that the sample satisfying the configuration of the present invention is excellent in terms of adhesion, fine line reproducibility, and conductivity.

1 is a schematic cross-sectional view showing an example of an ink jet recording apparatus including a pressure applying unit and an electric field applying unit that can be preferably applied to the present invention. It is a figure which shows the electroconductive pattern which has multiple types of wiring from which line and space differs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 Inkjet recording device 21 Nozzle 22 Flow path in nozzle 23 Counter electrode 24 Ink chamber 25 Discharge voltage application means 26 Nozzle plate 27 Supply path 28 Discharge electrode 30 Bias power supply K Base material

Claims (8)

A layer containing a photocatalytically active material is provided on a substrate, a solution containing a metal compound is disposed on the layer, and a metal pattern serving as a wiring is formed by photoreducing the metal in the metal compound by an exposure process. A process for producing a conductive pattern sheet characterized by the above. The method for producing a conductive pattern sheet according to claim 1, wherein the solution containing the metal compound is disposed by ink jet recording in which an ink jet recording apparatus performs injection drawing. 4. The method for producing a conductive pattern sheet according to claim 3, wherein the ink jet recording is a method using a pressure applying unit and an electric field applying unit. The method for producing a conductive pattern sheet according to claim 1, wherein the solution containing the metal compound is disposed on the entire surface of the layer containing the photocatalytic active material. The conductive pattern sheet according to any one of claims 1 to 4, wherein the metal of the solution containing the metal compound is at least one selected from copper, silver, gold, nickel, palladium, and zinc. Manufacturing method. The method for producing a conductive pattern sheet according to claim 1, further comprising an electroless plating treatment step or an electrolytic plating treatment step after the exposure step. It has the process of wash | cleaning the layer containing a photocatalytic active material after the said exposure process, The preparation method of the electroconductive pattern sheet of any one of Claims 1-6 characterized by the above-mentioned. The method for producing a conductive pattern sheet according to any one of claims 1 to 7, wherein the photocatalytically active material is titanium dioxide.

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