WO2019065234A1

WO2019065234A1 - Method for manufacturing substrate with electrodes formed thereon

Info

Publication number: WO2019065234A1
Application number: PCT/JP2018/033780
Authority: WO
Inventors: 橋本大樹; 高瀬皓平
Original assignee: 東レ株式会社
Priority date: 2017-09-26
Filing date: 2018-09-12
Publication date: 2019-04-04
Also published as: CN111133408A; JPWO2019065234A1; KR20200058330A; TW201921456A

Abstract

Provided is a method for manufacturing a substrate with electrodes formed thereon, wherein positional accuracy is excellent even when a thin film transparent substrate that is difficult to see is used, transmittance differences and moiré can be suppressed, and yield is high. This method for manufacturing a substrate with electrodes formed thereon in which a first electrode, an insulating layer, and a second electrode are formed on a first transparent substrate having a thickness of no greater than 200 μm comprises: a step for forming the first electrode on at least one surface of the first transparent substrate; a step for forming the insulating layer on the surface on which the first electrode of the transparent substrate is formed; and a step for forming the second electrode on the insulating layer, wherein the first electrode and/or the second electrode are opaque.

Description

Method of manufacturing substrate with electrode

The present invention relates to a method of manufacturing a substrate with an electrode having a transparent substrate, a first electrode, an insulating layer and a second electrode.

In recent years, touch panels have been widely used as input means. The touch panel includes a display unit such as a liquid crystal panel, and a touch panel sensor that detects information input to a specific position. The touch panel methods are roughly classified into a resistive film method, a capacitance method, an optical method, an electromagnetic induction method, an ultrasonic method, and the like according to a detection method of an input position. Among them, a capacitive touch panel is widely used for reasons of optically bright, excellent in design, simple in structure, and excellent in function.

The capacitive touch panel sensor has a second electrode which is orthogonal to the first electrode and the insulating layer, applies a voltage to the electrode on the touch panel surface, and the capacitance when a conductor such as a finger touches the electrode. The contact position obtained by detecting the change is output as a signal. As a touch panel sensor used in the capacitance method, for example, a structure in which two transparent substrates having a transparent electrode pattern formed on one surface of a transparent substrate are bonded, or electrodes are formed on both sides of one transparent substrate The structure formed etc. are known. As a wiring electrode used for a touch panel sensor, a transparent wiring electrode was generally used from the viewpoint of making the wiring electrode difficult to see, but in recent years, metal materials have been used due to high sensitivity and large screens. The opaque wiring electrode is widespread.

As a method of forming an opaque wiring electrode using a metal material, for example, a method is proposed in which a photosensitive conductive paste containing a conductive powder is applied, patterned by photolithography, and then fired (for example, Patent Document 1) reference). However, when the transparent substrate on which the opaque wiring electrode is formed is bonded to two or more layers or other substrates, there has been a problem that positional deviation easily occurs due to the mechanical accuracy of the bonding apparatus and the flexibility of the bonding adhesive member. . In particular, in the case where two or more layers of the transparent substrate on which the opaque wiring electrodes are formed are bonded to each other, if misalignment occurs, moire defects occur due to interference between the opaque wiring electrodes. Such problems become more remarkable as the transparent substrate becomes thinner.

On the other hand, as a method for producing a transparent conductive laminate easy to align, for example, at least a first transparent conductive layer and a second transparent conductive layer are formed on both sides of the transparent substrate layer, and the first transparent A method of applying a resist on the surface of the conductive layer and the second transparent conductive layer and simultaneously exposing it, developing the resist and etching the first transparent conductive layer and the second transparent conductive layer (for example, see Patent Document 2) ) Has been proposed. However, in such a method, the transparent substrate layer needs to absorb the exposure light in order to avoid exposure of other than the desired resist by simultaneous exposure, and since the materials which can be used are limited, another method is desirable. It was rare. In addition, a process of forming a first transparent electrode pattern on one side of a first transparent substrate, a process of forming at least a transparent conductive layer on one side of a second transparent substrate, and a process of forming the first transparent substrate A step in which the surface on which the transparent electrode pattern is not formed and the surface on which the transparent conductive layer of the second transparent substrate is not formed are opposed to each other and adhered with an adhesive layer, and the first transparent electrode pattern is used. There has been proposed a method including the steps of adjusting the exposure position of patterning of the transparent conductive layer and forming a second transparent electrode pattern on the transparent conductive layer by patterning (see, for example, Patent Document 3).

JP 2000-199954 A Patent No. 4683164 gazette JP, 2014-71802, A

However, in the method described in Patent Document 3, there is a problem that the exposed first transparent electrode pattern tends to be deficient or broken at the time of forming the second transparent conductive pattern, and the yield is low. The present invention has been made in view of the above-described circumstances, and provides a method of manufacturing a substrate with a high yield, which is difficult to be visually recognized, is excellent in positional accuracy even using a thin film transparent substrate, and can suppress moire. The purpose is to

In order to solve the above-mentioned subject, the present invention mainly has the following composition.
A method of manufacturing a substrate with an electrode having a first electrode, an insulating layer and a second electrode on a first transparent substrate having a thickness of 200 μm or less, wherein the first transparent substrate has at least one side thereof. The method includes the steps of forming an electrode, forming an insulating layer on the surface of the transparent substrate on which the first electrode is formed, and forming a second electrode on the insulating layer, Forming the second electrode and heating the second electrode at a temperature of 100.degree. C. to 150.degree. C., the first electrode and / or the second electrode being opaque. Method of manufacturing a substrate

According to the present invention, it is possible to obtain a substrate with an electrode which is hard to be recognized and which is excellent in positional accuracy even when using a thin film transparent substrate and which can suppress moire with high yield.

It is the schematic which shows an example of a structure of the board | substrate with an electrode based on the manufacturing method of this invention. It is the schematic which shows another example of a structure of the board | substrate with an electrode based on the manufacturing method of this invention. It is the schematic which shows another example of a structure of the board | substrate with an electrode based on the manufacturing method of this invention. It is the schematic which shows another example of a structure of the board | substrate with an electrode based on the manufacturing method of this invention. It is the schematic which shows another example of a structure of the board | substrate with an electrode based on the manufacturing method of this invention. It is the schematic which shows another example of a structure of the board | substrate with an electrode based on the manufacturing method of this invention. It is the schematic which shows an example which overlap | superposed the 1st electrode and 2nd electrode for position accuracy evaluation in an Example and a comparative example. It is the schematic which shows the 1st electrode for moire evaluation in an Example and a comparative example. It is the schematic which piled up the 1st electrode and 2nd electrode for moire evaluation in an Example and a comparative example. It is the schematic which shows the mesh shape of the opaque wiring electrode for moire evaluation in an Example and a comparative example.

A substrate with an electrode based on the manufacturing method of the present invention has a first electrode, an insulating layer and a second electrode on a first transparent substrate. First, each of these layers will be described.

(First transparent substrate)
The first transparent substrate is a portion to be a base of the electrode-attached substrate, and is preferably transparent in the visible light region. Specifically, the transmittance of light having a wavelength of 550 nm is preferably 80% or more, and more preferably 85% or more. The transmittance of the first transparent substrate at a wavelength of 550 nm can be measured using an ultraviolet-visible spectrophotometer (U-3310 manufactured by Hitachi High-Technologies Corporation).

As a transparent substrate, for example, quartz glass, soda glass, chemically tempered glass, "Pyrex" (registered trademark) glass, synthetic quartz plate, epoxy resin substrate, polyetherimide resin substrate, polyether ketone resin substrate, polysulfone resin substrate And transparent films made of resins such as polyethylene terephthalate film (hereinafter, "PET film"), cycloolefin polymer film, polyimide film, polyester film, aramid film, etc., and resin plates for optics. Among these, PET films, cycloolefin polymer films, and polyimide films are preferable from the viewpoint of transparency, heat resistance, and strength when the thickness is 200 μm or less. A plurality of these may be stacked and used, and for example, it can be used by bonding using a plurality of transparent substrates by an adhesive layer.

Moreover, the functional film which has various functions, such as ultraviolet-ray cutability, gas-barrier property, anti-reflective property, as a transparent substrate is mentioned. As a functional film having an ultraviolet ray cutting property, for example, a film made of a resin having an ultraviolet ray absorbing property such as polyethylene naphthalate or the transparent film exemplified above has a maximum absorption wavelength in the ultraviolet ray region of a wavelength of 300 to 380 nm. The film which added the ultraviolet absorber, and the laminated film etc. in which the insulating layer containing an ultraviolet absorber was formed in single side | surface or both surfaces to the transparent film illustrated above are mentioned. 60% or less is preferable, as for the transmittance | permeability of the light of wavelength 365 nm of the functional film which has ultraviolet-ray cutting property, 40% or less is more preferable, and 20% or less is more preferable. Examples of the functional film having gas barrier properties include laminates in which a metal oxide layer such as silicon oxide is formed on the transparent film exemplified above. Water vapor permeability of the functional film having a gas barrier property, 1 × preferably ¹⁰ -1 ^{g /} m 2 · day or less, more preferably ^{^{1 × 10 -2 g / m 2}} · day, 1 × 10 -3 g It is more preferable to use / m ² · day or less. Here, the water vapor transmission rate can be measured at 40 ° C. in a 90% RH atmosphere using a water vapor transmission rate measuring device (MOCON PERMATRAN 3/21 manufactured by Modern Control Co., Ltd.). A laminate obtained by forming a low refractive index layer or a high refractive index layer formed of a thin film material such as metal oxide, nitride or fluoride on the transparent film exemplified above as a functional film having an antireflective property Etc. The material for forming the low refractive index layer is preferably a low refractive index material having a refractive index of 1.6 or less at a wavelength of 550 nm, and examples thereof include silicon oxide and magnesium fluoride. As a material for forming the high refractive index layer, a high refractive material having a refractive index of 1.9 or more at a wavelength of 550 nm is preferable. For example, titanium oxide, niobium oxide, zirconium oxide, tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO) etc. In addition to the low refractive index layer and the high refractive index layer, as a middle refractive index layer having a refractive index of about 1.50 to 1.85, for example, a thin film made of titanium oxide or a mixture of the low refractive index material and the high refractive material May be formed.

According to the present invention, according to the prior art, it can be suitably used when using a transparent substrate which is easily displaced. Therefore, the thickness of the first transparent substrate in the present invention is 200 μm or less in total. When the thickness of the first transparent substrate is thicker than 200 μm, the flexibility of the transparent substrate is small, so the transparent substrate on which the opaque wiring electrode is formed is bonded to two or more layers or other substrates. However, misalignment does not easily occur.

(First electrode, second electrode)
The first electrode and / or the second electrode are opaque. Specifically, the transmittance of light with a wavelength of 365 nm is preferably 20% or less, and more preferably 10% or less. The transmittance of the first electrode and the second electrode is measured by a micro-spectral spectral color difference meter (VSS 400: manufactured by Nippon Denshoku Kogyo Co., Ltd.) for an electrode of 0.1 mm square or more on the transparent substrate. can do. The first electrode and the second electrode may be composed of the same material or may be composed of different materials. Preferably, one of the first electrode or the second electrode is opaque and the other is transparent. By having a transparent electrode, an electrode can be formed using existing production equipment without using expensive silver and the like.

As a pattern shape of a 1st electrode and a 2nd electrode, mesh shape, stripe shape etc. are mentioned, for example. As the mesh shape, for example, a lattice shape in which a unit shape is a lattice shape such as a triangle, a quadrangle, a polygon, a circle, or a combination of these unit shapes, and the like can be mentioned. Among them, the mesh shape is preferable from the viewpoint of making the conductivity of the pattern uniform. The first electrode and the second electrode are more preferably a metal mesh that is made of metal and has a mesh-like pattern. Since the metal mesh has high conductivity, it can be easily miniaturized to a line width which is difficult to be visually recognized.

From the viewpoint of conductivity, the thickness of the opaque electrode among the first electrode and the second electrode is preferably 0.01 μm or more, more preferably 0.05 μm or more, and still more preferably 0.1 μm or more. On the other hand, the thickness of the opaque electrode is preferably 10 μm or less, more preferably 5 μm or less, and still more preferably 3 μm or less, from the viewpoint of forming finer wiring.

The line width of the patterns of the first electrode and the second electrode is preferably 1 μm or more, more preferably 1.5 μm or more, and still more preferably 2 μm or more, from the viewpoint of further improving the conductivity. On the other hand, the line width of the patterns of the first electrode and the second electrode is preferably 10 μm or less, more preferably 7 μm or less, and still more preferably 6 μm or less, from the viewpoint of making the wiring electrode less visible.

As a material which forms an opaque electrode among the first electrode and the second electrode, for example, silver, gold, copper, platinum, lead, tin, nickel, aluminum, tungsten, molybdenum, chromium, titanium, indium, etc. Metals, alloys thereof and the like can be mentioned. Two or more of these may be used. Among these, conductive particles such as silver, copper and gold are preferable from the viewpoint of conductivity.

The primary particle diameter of the conductive particles is preferably 0.1 to 1.0 μm, more preferably 0.2 to 0.8 μm, in order to form a fine conductive pattern having desired conductivity. Here, the primary particle diameter of the conductive particles means that the electrode is physically collected with tweezers, adhesive tape, etc., the resin component is dissolved with an organic solvent such as tetrahydrofuran, the precipitated conductive particles are collected, and the box is The sample dried at 70 ° C. for 10 minutes using an oven was observed at a magnification of 25000 using an electron microscope, and the major and minor axes of the primary particles of 100 randomly selected conductive particles were measured. , And can be calculated by obtaining their number average value. The organic solvent used to dissolve the resin component is not particularly limited as long as it can dissolve the resin component of the electrode.

When the opaque electrode contains conductive particles among the first electrode and the second electrode, the content thereof is preferably 60% by mass or more, more preferably 65% by mass or more, from the viewpoint of improving the conductivity. 70% by mass or more is more preferable. On the other hand, from the viewpoint of improving pattern processability, the content of the conductive particles is preferably 95% by mass or less, more preferably 90% by mass or less, and still more preferably 85% by mass or less. In addition, content of the electroconductive particle in an opaque electrode can be calculated | required by measuring a baking residue using a thermogravimetric analyzer about an opaque electrode.

Among the first electrode and the second electrode, the opaque electrode preferably contains an organic compound together with the aforementioned metal.

As an organic compound, alkali-soluble resin is preferable. As alkali-soluble resin, resin etc. which have a hydroxyl group and / or a carboxyl group are mentioned, for example. As a resin having a hydroxy group, for example, a phenol novolak resin having a phenolic hydroxy group, a novolak resin such as a cresol novolac resin, a polymer of a monomer having a hydroxy group, a monomer having a hydroxy group, styrene, acrylonitrile, an acrylic monomer, etc. And copolymers thereof.

As the monomer having a hydroxy group, for example, monomers having a phenolic hydroxy group such as 4-hydroxystyrene, hydroxyphenyl (meth) acrylate and the like; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate , (Meth) acrylic acid 3-methyl-3-hydroxybutyl, (meth) acrylic acid 1,1-dimethyl-3-hydroxybutyl, (meth) acrylic acid 1,3-dimethyl-3-hydroxybutyl, (meth) 2,2,4-trimethyl-3-hydroxypentyl acrylate, 2-ethyl-3-hydroxyhexyl (meth) acrylate, glycerol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate Such as acrylate Monomers having a phenolic hydroxy group.

As resin which has a carboxyl group, for example, carboxylic acid modified epoxy resin, carboxylic acid modified phenol resin, polyamic acid resin, carboxylic acid modified siloxane resin, polymer of monomer having carboxyl group, monomer having carboxyl group, styrene, acrylonitrile And copolymers with acrylic monomers and the like.

Examples of the monomer having a carboxyl group include acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid, cinnamic acid and the like.
As the resin having a hydroxy group and a carboxyl group, a copolymer of a monomer having a hydroxy group and a monomer having a carboxy group, a monomer having a hydroxy group, a monomer having a carboxy group, styrene, acrylonitrile, an acrylic monomer, etc. Copolymers may be mentioned. Two or more of these may be contained.

Among them, resins containing a phenolic hydroxy group and a carboxyl group are preferred. When a quinone diazide compound is used as a photosensitizer by containing a phenolic hydroxy group, the phenolic hydroxy group and the quinone diazide compound form a hydrogen bond, and the developer in the unexposed area of the positive photosensitive light shielding composition layer The solubility difference between the unexposed area and the exposed area is increased, and the development margin can be expanded. Moreover, by containing a carboxyl group, the solubility to a developing solution improves, and adjustment of development time becomes easy by content of a carboxyl group. Further, by containing a carboxyl group, conductivity can be exhibited at a lower temperature.

The acid value of the alkali-soluble resin having a carboxyl group is preferably 50 mg KOH / g or more from the viewpoint of solubility in a developing solution, and 250 mg KOH / g or less from the viewpoint of suppressing excessive dissolution of the unexposed area. The acid value of the alkali-soluble resin having a carboxyl group can be measured according to JIS K 0070 (1992).

Among the first electrode and the second electrode, the opaque electrode is, if necessary, a dispersant, a photopolymerization initiator, a monomer having an unsaturated double bond, a photoacid generator, a thermal acid generator, a sensitization It may contain an agent, a pigment or dye that absorbs visible light, an adhesion improver, a surfactant, a polymerization inhibitor, and the like.

As a material which forms a transparent electrode among the first electrode and the second electrode, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide Substances (IZTO), cadmium tin oxide (CTO), PEDOT (poly (3,4-ethylenedioxythiophene)), carbon nanotubes (CNT), metal wires and the like. Two or more of these may be used. Among these, indium tin oxide (ITO) is preferable.

From the viewpoint of conductivity, the thickness of the transparent electrode is preferably 16 nm or more, more preferably 18 nm or more, and still more preferably 20 nm or more. On the other hand, the thickness of the transparent electrode is preferably 40 nm or less, more preferably 38 nm or less, and still more preferably 36 nm or less, from the viewpoint of transparency and color.

The surface resistance of the substrate with a transparent electrode is preferably 10 to 400 Ω / □. When using for an electrostatic capacitance type touch panel, from a viewpoint of a sensitivity, 300 ohms / square or less are more preferable, and 270 ohms / square or less are further more preferable.

(Insulating layer)
The insulating layer is a portion that secures insulation between the first electrode and the second electrode. As a material which constitutes an insulating layer, for example, insulating resin materials such as polyimide resin, acrylic resin, cardo resin, epoxy resin, melamine resin, urethane resin, silicon resin, fluorine resin, etc., inorganic materials such as glass Etc. Two or more of these may be used. An insulating resin material is preferable from the viewpoint of strength against bending and bending of the transparent substrate. The insulating layer may be a multilayer including two or more layers. In the present invention, the insulating layer preferably has a multilayer structure including an adhesive layer and a second transparent substrate. By having a multilayer structure including the adhesive layer and the second transparent substrate, a transparent substrate with high surface smoothness can be used, and the positional accuracy of the first electrode and the second electrode can be further improved.

(Adhesive layer, second transparent substrate)
The adhesive layer has a function to adhere a plurality of layers to be adhered in a short time with a slight pressure under room temperature and / or heating conditions. In the present invention, it is preferable to bond the first transparent substrate having the first electrode and the second transparent substrate.

The adhesive layer preferably has transparency. Examples of the material constituting the adhesive layer include acrylic resin, silicone resin, urethane resin, polyamide resin, polyvinyl ether resin, vinyl acetate / vinyl chloride copolymer, modified polyolefin resin, fluorine resin, natural rubber, synthetic rubber, etc. Can be mentioned. Two or more of these may be used. Among these, acrylic resins are preferable from the viewpoint of excellent transparency, adhesion properties such as appropriate wettability, cohesion and adhesiveness, and excellent weather resistance and heat resistance. The adhesive layer may contain, as necessary, a tackifier, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a silane coupling agent, and the like.

The thickness of the adhesive layer is preferably 1 μm or more, more preferably 3 μm or more, and still more preferably 5 μm or more. On the other hand, 100 micrometers or less are preferable, as for the thickness of an adhesion layer, 50 micrometers or less are more preferable, and 35 micrometers or less are more preferable.

As an aspect of a 2nd transparent substrate, what was illustrated as an aspect of a 1st transparent substrate, a polarizing film, etc. are mentioned. The polarizing film refers to a film having a polarizing ability to transmit only polarized light in a certain vibration direction. As a polarizing film, the film etc. which dyed and adsorb | sucked iodine and dye to polyvinyl alcohol, and were made to extend | stretch and orient are mentioned, for example. The first transparent substrate and the second transparent substrate may be made of the same material or may be made of different materials.

The thickness of the insulating layer is preferably 0.1 μm to 300 μm, more preferably 0.5 μm to 200 μm, and still more preferably 0.8 μm to 150 μm, from the viewpoints of insulation, moist heat resistance, and transparency.

1 to 6 show schematic views of an example of the configuration of a substrate with an electrode based on the manufacturing method of the present invention. FIG. 1 schematically shows an electrode-equipped substrate having a first electrode, an opaque electrode 2 and an insulating layer 3 on a transparent substrate 1, and further having an opaque electrode 2 as a second electrode on an insulating layer 3. FIG. FIG. 2 is a schematic view of a substrate with an electrode having the first electrode, the opaque electrode 2 and the insulating layer 3 on the transparent substrate 1 and the transparent electrode 4 as the second electrode on the insulating layer 3. FIG. FIG. 3 schematically shows an electrode-equipped substrate having a transparent electrode 4 as a first electrode and an insulating layer 3 on a transparent substrate 1 and further having an opaque electrode 2 as a second electrode on the insulating layer 3. FIG. FIGS. 4 to 6 are schematic views of a substrate with an electrode when the insulating layer 3 in FIGS. 1 to 3 is the adhesive layer 5 and the second transparent substrate 6.

Next, each step in the method of manufacturing a substrate with electrode of the present invention will be described in detail.

First, a first electrode is formed on at least one side of a first transparent substrate. The first electrode may be a transparent electrode or an opaque electrode.

As a method of forming the first electrode, in the case of a transparent electrode, for example, dry coating such as PVD method such as sputtering or vapor deposition, CVD method, spin coating using a spinner, roll coating, spray coating, dip coating, etc. Examples of the method include a method of forming a film formed into a pattern by a wet process or a dry process. From the viewpoint of patterning only the transparent electrode, a wet process is preferable, and a photolithography method is more preferable. On the other hand, in the case of an opaque electrode, for example, a method of forming a pattern by photolithography using a photosensitive conductive paste, a method of forming a pattern by screen printing, gravure printing, ink jet etc using a conductive paste, metal, metal composite, A method of forming a film of a complex of a metal and a metal compound, a metal alloy or the like and forming the film by a photolithography method using a resist can be mentioned. Among these, since the fine wiring can be formed, the method of forming by a photolithographic method using a photosensitive conductive paste is preferable.

As a film forming method for forming a transparent electrode, dry coating is preferable and sputtering is more preferable because a thin film at the nanometer level can be easily formed. As a gas used for sputtering, what has an inert gas as a main component is preferable, and mixed gas of argon and oxygen is more preferable.

It is preferable to form a pattern by etching a part of the obtained film. A photoresist, a developer, an etchant, and a rinse agent used for etching can be arbitrarily selected and used so that a predetermined pattern can be formed without the transparent electrode being corroded.

The photosensitive conductive paste used to form the opaque electrode includes the above-mentioned conductive particles, an alkali-soluble resin, a dispersant, a photopolymerization initiator, a monomer having an unsaturated double bond, a photoacid generator, a thermal acid generator, A sensitizer, a pigment, a dye, an adhesion improver, a surfactant, a polymerization inhibitor, a solvent and the like can be contained as needed.

As a method of applying the photosensitive conductive paste, for example, spin coating using a spinner, spray coating, roll coating, screen printing, offset printing, gravure printing, letterpress printing, flexo printing, blade coater, die coater, calendar coater, meniscus cove A method using a tar or a bar coater. Above all, screen printing is preferable because it is excellent in the surface flatness of the composition film of the photosensitive conductive paste to be obtained, and the film thickness adjustment is easy by the selection of the screen plate.

When the photosensitive conductive paste contains a solvent, it is preferable to dry the composition film of the applied photosensitive conductive paste to volatilize and remove the solvent. As a drying method, for example, heat drying, vacuum drying and the like can be mentioned. The heating and drying apparatus may be one that heats by electromagnetic waves or microwaves, and examples thereof include an oven, a hot plate, an electromagnetic wave ultraviolet lamp, an infrared heater, a halogen heater and the like. The heating temperature is preferably 50 ° C. or more, and more preferably 70 ° C. or more, from the viewpoint of suppressing the remaining of the solvent. On the other hand, the heating temperature is preferably 130 ° C. or less, more preferably 110 ° C. or less, from the viewpoint of suppressing the deactivation of the photosensitizer. The heating time is preferably 1 minute to several hours, more preferably 1 minute to 50 minutes.

As a pattern formation method by the photolithography method, a method of exposing and developing is preferable. For example, when the photosensitive conductive paste has negative photosensitivity, the unexposed area can be removed to form a desired pattern by developing the composition film of the exposed photosensitive conductive paste.

The exposure light preferably emits light in the ultraviolet region that matches the absorption wavelength of the photosensitive agent contained in the photosensitive conductive paste, that is, in the wavelength region of 200 nm to 450 nm. As a light source for obtaining such exposure light, a mercury lamp, a halogen lamp, a xenon lamp, an LED lamp, a semiconductor laser, a KrF, an ArF excimer laser etc. are mentioned, for example. Among these, the i-line (wavelength 365 nm) of a mercury lamp is preferable. The exposure dose is preferably 50 mJ / cm ² or more, more preferably 100 mJ / cm ² or more, and still more preferably 200 mJ / cm ² or more in terms of wavelength 365 nm from the viewpoint of solubility of the exposed portion in the developer.

As a developing solution, what does not inhibit the electroconductivity of a 1st electrode is preferable, and an alkali developing solution is preferable. Examples of the alkali development include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, sodium metasilicate and aqueous ammonia; primary amines such as ethylamine and n-propylamine; Secondary amines such as diethylamine and di-n-propylamine; tertiary amines such as triethylamine and methyl diethylamine; tetraalkyl ammonium hydroxides such as tetramethyl ammonium hydroxide (TMAH); quaternary ammonium salts such as choline Alcohol amines such as triethanolamine, diethanolamine, monoethanolamine, dimethylaminoethanol and diethylaminoethanol; pyrrole, piperidine, 1,8-diazabicyclo [5,4,0] -7-undecene, , 5-diazabicyclo [4,3,0] -5-nonane, include aqueous solutions of alkaline substances such as organic alkalis such cyclic amines such as morpholine and the like. To these aqueous solutions, water-soluble organic solvents such as ethanol, γ-butyrolactone, dimethylformamide, N-methyl-2-pyrrolidone and the like, and surfactants such as nonionic surfactants may be added.

As a developing method, for example, a method of spraying a developing solution on the surface of the composition film of the photosensitive conductive paste while allowing the substrate on which the composition film of the photosensitive conductive paste is formed to stand, rotate or transport the photosensitive conductive paste And a method of immersing the composition film of the photosensitive conductive paste in a developer while applying the ultrasonic wave.

The pattern obtained by development may be subjected to a rinse treatment with a rinse solution. Examples of the rinse solution include water; aqueous solutions of alcohols such as ethanol and isopropyl alcohol; and aqueous solutions of esters such as ethyl lactate and propylene glycol monomethyl ether acetate.

The obtained transparent electrode or opaque electrode may be heated, preferably in air. The heating temperature is preferably 100 ° C. or more, and more preferably 120 ° C. or more, from the viewpoint of sufficiently curing and improving the conductivity. On the other hand, the heating temperature is preferably 150 ° C. or less, more preferably 140 ° C. or less, from the viewpoints of heat resistance of the transparent substrate and positional accuracy and visibility when using a thin film transparent substrate. In the step of forming the first electrode and the step of forming the second electrode, having the step of heating at a temperature of 100 ° C. or more and 150 ° C. or less is a position accuracy when using a conductive thin film transparent substrate And particularly preferred in view of visibility.

Next, as a method of forming an insulating layer in which an insulating layer is formed on the surface of the transparent substrate on which the first electrode is formed, the method exemplified as the method of forming an opaque electrode using a photosensitive conductive paste may be mentioned. When the insulating layer has a pressure-sensitive adhesive layer and a second transparent substrate, as a method of forming the pressure-sensitive adhesive layer, for example, a method of transferring an adhesive onto a release liner and then transferring it to a transparent substrate (transfer method), transparent substrate Directly apply and dry the pressure-sensitive adhesive (direct printing method), co-extrusion and the like.

When the insulating layer has a pressure-sensitive adhesive layer and a second transparent substrate, it is preferable that the first electrode and the second transparent substrate be attached to each other with the pressure-sensitive adhesive layer interposed therebetween. At the time of bonding, in order to remove air bubbles in the vicinity of the non-flat portion of the first electrode, defoaming is preferable. Since the surface smoothness of the second transparent substrate is improved by degassing, the positional accuracy of the first electrode and the second electrode can be further improved. As a degassing method, methods, such as heating, pressurization, pressure reduction, are mentioned, for example. For example, it is preferable to make the first electrode and the second transparent substrate face each other and to bond them while suppressing mixing of air bubbles under reduced pressure and heating. Thereafter, for the purpose of suppressing delay bubbles, it is preferable to apply heat and pressure by autoclave treatment or the like. 30 degreeC or more is preferable from a viewpoint of degassing efficiency at the time of heating-pressing, and 40 degreeC or more is more preferable. On the other hand, the heating temperature is preferably 150 ° C. or less, more preferably 130 ° C. or less, and still more preferably 120 ° C. or less, from the viewpoint of further suppressing the thermal contraction of the transparent substrate and the adhesive layer. Further, the pressure at the time of heating and pressurizing is preferably 0.05 MPa or more, and more preferably 0.1 MPa or more from the viewpoint of degassing efficiency. On the other hand, the pressure is preferably 2.0 MPa or less, more preferably 1.5 MPa or less, and still more preferably 1.0 MPa or less, from the viewpoint of further suppressing the bending of the substrate and the adhesive layer.

Further, a second electrode is formed on the insulating layer. The second electrode can be formed by the same method as the first electrode. The method for producing a substrate with an electrode according to the present invention, in which the second electrode is formed on the insulating layer, is more prominent as the transparent substrate becomes thinner as compared to the method in which two or more substrates with electrodes are bonded. It is possible to suppress the positional deviation due to the flexibility of the above and improve the positional accuracy. In addition, since the insulating layer protects the first electrode, erosion of the developer on the first electrode in the developing step during formation of the second electrode and contact between the first electrode and equipment due to handling are suppressed. Thus, it is possible to improve the yield by suppressing defects such as wire breakage and disconnection.

In the present invention, in patterning of the second electrode, alignment can be performed using the first electrode pattern already formed. Specifically, in the exposure step of the second electrode, the first electrode pattern is detected using a camera, and the position of the first electrode pattern and the second electrode pattern is adjusted by adjusting the stage of the exposure apparatus. Deviation can be further suppressed, and position accuracy can be further improved.

The substrate with an electrode obtained by the manufacturing method of the present invention is difficult to be recognized visually, is excellent in positional accuracy, and can suppress moire, so it is suitable for, for example, a member for touch panel, a member for electromagnetic shielding, a member for transparent LED light, etc. It can be used for Above all, it can be suitably used as a member for a touch panel which is required to be more difficult to visually recognize the wiring electrode.

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto.

The materials used in each example are as follows. The transmittance of the transparent substrate at a wavelength of 550 nm was measured using an ultraviolet-visible spectrophotometer (U-3310 manufactured by Hitachi High-Technologies Corporation).

(Transparent substrate)
“Lumirror” (registered trademark) T60 (manufactured by Toray Industries, Inc.) (thickness: 100 μm, transmittance at a wavelength of 550 nm: 89%) (a-1)
"Zeonex" (registered trademark) 480 (manufactured by Nippon Zeon Co., Ltd.) (thickness: 100 μm, transmittance at a wavelength of 550 nm: 92%) (a-2).

Production Example 1: Carboxyl Group-Containing Acrylic Copolymer
In a nitrogen atmosphere reaction vessel, 150 g of diethylene glycol monoethyl ether acetate (hereinafter, “DMEA”) was charged, and the temperature was raised to 80 ° C. using an oil bath. In this, 20 g of ethyl acrylate (hereinafter, "EA"), 40 g of 2-ethylhexyl methacrylate (hereinafter, "2-EHMA"), 20 g of styrene (hereinafter, "St"), 15 g of acrylic acid (hereinafter, A mixture consisting of "AA"), 0.8 g of 2,2-azobisisobutyronitrile and 10 g of diethylene glycol monoethyl ether acetate was added dropwise over 1 hour. After completion of the dropwise addition, the mixture was further stirred for 6 hours to carry out a polymerization reaction. Thereafter, 1 g of hydroquinone monomethyl ether was added to terminate the polymerization reaction. Subsequently, a mixture consisting of 5 g of glycidyl methacrylate (hereinafter "GMA"), 1 g of triethylbenzene ammonium chloride and 10 g of DMEA was dropped over 0.5 hours. After completion of the dropwise addition, the mixture was further stirred for 2 hours to carry out an addition reaction. Unreacted impurities are removed by purifying the resulting reaction solution with methanol, and vacuum drying is further performed for 24 hours to obtain a copolymerization ratio (by mass): EA / 2-EHMA / St / GMA / AA = 20/40. A carboxyl group-containing acrylic copolymer of / 20/5/15 was obtained. It was 103 mgKOH / g when the acid value of the obtained copolymer was measured. The acid value was measured in accordance with JIS K 0070 (1992).

(Production Example 2: Photosensitive Conductive Paste)
In a 100 mL clean bottle, 17.5 g of the carboxyl group-containing acrylic copolymer obtained according to Production Example 1 0.5 g of a photopolymerization initiator N-1919 (manufactured by ADEKA Co., Ltd.), 1.5 g of an epoxy resin "Adeka Resin" (registered trademark) EP-4530 (epoxy equivalent 190, manufactured by ADEKA Corporation), 3.5 g of monomer "Light Acrylate" (registered trademark) BP-4EA (manufactured by Kyoeisha Chemical Co., Ltd.) and 19.0 g The DMEA was added and mixed using “Awatori sakutaro” (registered trademark) ARE-310 (manufactured by Shinky Co., Ltd.) to obtain 42.0 g of a resin solution. The obtained 42 g of resin solution and 62.3 g of primary particles having a primary particle diameter of 0.4 μm are mixed and kneaded using a 3-roller EXAKT M50 (manufactured by EXAKT), and 7 g of DMEA is further added and mixed. To give 111 g of photosensitive conductive paste. The viscosity of the photosensitive conductive paste was 10,000 mPa · s. The viscosity was measured using a Brookfield viscometer at a temperature of 25 ° C. and a rotational speed of 3 rpm.

(Production Example 3: Insulating Composition)
In a 100 mL clean bottle, place 20.0 g of Polymeric Acrylate “UNIDIC” ® V6840, 0.5 g of Photopolymerization Initiator “IRGACURE” ® IC 184, 10.0 g of isobutyl ketone, The mixture was mixed using Tori-Shintaro "(registered trademark) ARE-310 (manufactured by Shinky Co., Ltd.) to obtain 30.5 g of an insulating composition.

Evaluation in each example and comparative example was performed by the following methods.

(1) Positional Accuracy With respect to the substrate with electrodes produced in each of the Examples and the Comparative Examples, the positional deviation amount X is measured in the portion where the first electrode and the second electrode for positional accuracy evaluation shown in FIG. The case where the amount of displacement was less than 10 μm was evaluated as A, and the case where the amount of displacement was 10 μm or more was evaluated as B. The pattern for position accuracy evaluation was a circle with a diameter of 2 mm, and the width of the pattern was 240 μm.

(2) Visibility An electrode-coated substrate having a first electrode having the outer shape shown in FIGS. 8 to 9 and a second electrode having the outer shape shown in FIG. The display was placed on a Flattron 23 EN 43 V-B2 23-type wide liquid crystal monitor (manufactured by LG Electronics), and the presence or absence of moiré was observed. However, in the electrode-attached substrate, the opaque electrode was formed by patterning the inside of the outer shape into a mesh shown in FIG. 10, and the transparent electrode was formed into a solid pattern in the entire inside of the outer shape.

(3) Yield A tester for measuring resistance (2407A; made by BK Precision Co., Ltd.) for 100 first electrodes of a substrate with an electrode having a first electrode having the outer shape shown in FIG. 8 manufactured according to each example and comparative example. The resistance value was measured using. Next, after forming the second electrode, the resistance value of the first 100 electrodes was measured again. The rate of change of the resistance value of each first electrode (the resistance value of the first electrode after the formation of the second electrode / the resistance value of the first electrode after the formation of the first electrode) is calculated. The case where all the 100 change rates were 110% or less was evaluated as A, and the case where one or more first electrodes whose change rates exceeded 110% were present was evaluated as B.

Example 1
<Formation of first electrode (opaque electrode)>
The photosensitive conductive paste obtained in Production Example 2 was printed on a transparent substrate (a-1) by screen printing so as to have a thickness of 1 μm after drying, and dried at 100 ° C. for 10 minutes. An exposure apparatus (PEM-6M; manufactured by Union Optics Co., Ltd.) was used for exposure at an exposure dose of 500 mJ / cm ² (converted to a wavelength of 365 nm) through an exposure mask having a pattern of the shape shown in FIGS. The mask opening width was 3 μm. Thereafter, immersion development is performed for 30 seconds in a 0.2 mass% sodium carbonate aqueous solution, and after rinsing with ultrapure water, heating is performed for 30 minutes in an IR heater furnace at 140 ° C. to form a first electrode (opaque electrode) To obtain an electroded substrate having a first electrode having the outer shape shown in FIGS. It was 5% when the transmittance | permeability in wavelength 365 nm of the opaque electrode was measured with the micro surface-spectral-color-difference meter (VSS 400: Nippon Denshoku Kogyo Co., Ltd. product).

<Formation of insulating layer>
The insulating composition obtained by Production Example 3 is spin-coated at 1000 rpm for 5 seconds using a spin coater on a substrate on which the first electrode is formed, and then prebaked at 100 ° C. for 2 minutes using a hot plate, A pre-bake film was produced. Using a parallel light mask aligner, an ultrahigh pressure mercury lamp was used as a light source, and the pre-bake film was exposed through a desired exposure mask to form an insulating layer. The thickness of the insulating layer was 1 μm.

<Formation of Second Electrode (Opaque Electrode)>
On the formed insulating layer, a second electrode (opaque electrode) was formed by the same operation as the first electrode, to obtain a substrate with an electrode. However, as the exposure mask, one having a pattern of the shape shown in FIG. 7 and FIG. 9 was used. The results evaluated by the above-mentioned method are shown in Table 1.

(Example 2)
By the same operation as in Example 1, the first electrode (opaque electrode) and the insulating layer were formed on the transparent substrate (a-1).

<Formation of Second Electrode (Transparent Electrode)>
On the formed insulating layer, using indium tin oxide (tin oxide content: 5% by weight) as a target, in a mixed gas of argon / oxygen (volume ratio) 1/100, at an internal pressure of 0.5 Pa, Sputtering was performed at a temperature of 25 ° C. and a power density of 2.2 W / cm ² to form an ITO layer. The thickness of the obtained ITO layer was 25 nm. On the formed ITO layer, a photoresist (product name: TSMR-8900 (manufactured by Tokyo Ohka Kogyo Co., Ltd.)) was applied by spin coating to a film thickness of about 2 μm. This was prebaked in an oven at 90 ° C., and then exposed at 40 mJ / cm ² (converted to a wavelength of 365 nm) through an exposure mask having a pattern of the shape shown in FIGS. 7 and 9. Then, after post-baking at 110 ° C., the photoresist was patterned using a 25 ° C. developer (0.75 mass% aqueous NaOH solution). Furthermore, patterning was performed by etching the ITO film using an etching solution (product name: ITO-02 (manufactured by Kanto Chemical Co., Ltd.)). The remaining photoresist was removed using a stripping solution (2% by mass aqueous NaOH solution) at 40 ° C., followed by drying at 150 ° C. for 30 minutes to form a second electrode (transparent electrode) to obtain a substrate with an electrode. . The results evaluated by the above-mentioned method are shown in Table 1.

(Example 3)
The first electrode (transparent electrode) was formed on the transparent substrate (a-1) by the same operation as the method of forming the second electrode (transparent electrode) in Example 2. However, as the exposure mask, one having a pattern of the shape shown in FIG. 7 and FIG. 8 was used. Furthermore, by the same operation as in Example 1, an insulating layer and a second electrode (opaque electrode) were formed to obtain a substrate with an electrode. The results evaluated by the above-mentioned method are shown in Table 1.

(Example 4)
A first electrode (opaque electrode), an insulating layer, and a second electrode (opaque electrode) were formed on the transparent substrate (a-2) in the same manner as in Example 1 to obtain a substrate with an electrode. The results evaluated by the above-mentioned method are shown in Table 1.

(Example 5)
The first electrode (opaque electrode) was formed on the transparent substrate (a-1) in the same manner as in Example 1. An adhesive sheet “Panaclean” (registered trademark) PD-R5 (Panac) is made to face the first electrode of the substrate on which the first electrode is formed and the second transparent substrate (a-1) separately prepared. (Inc.) (Thickness: 25 μm), bonding was carried out under the conditions of heating temperature: 50 ° C., pressure: 0.2 MPa, to form an insulating layer consisting of an adhesive layer and a second transparent substrate. A second electrode (opaque electrode) was formed on the second transparent substrate by the same operation as in Example 1. The results evaluated by the above-mentioned method are shown in Table 1.

(Example 6)
An insulating layer comprising a first electrode (opaque electrode), an adhesive layer and a second transparent substrate in the same manner as in Example 5 with the first transparent substrate and the second transparent substrate as (a-2) The second electrode (opaque electrode) was formed to obtain a substrate with an electrode. The results evaluated by the above-mentioned method are shown in Table 1.

(Comparative example 1)
On a transparent substrate (a-1), by the same operation as in Example 1, two sheets of a substrate with an opaque electrode on which an opaque electrode was formed were produced. The adhesive sheet "Panaclean" (registered trademark) PD-R5 (Panuc) is made to face the surface of the substrate with opaque electrode on which the opaque electrode is formed and the surface of the other substrate with opaque electrode on which the opaque electrode is not formed. (Thickness: 25 μm), bonding is performed under the conditions of heating temperature: 50 ° C., pressure: 0.2 MPa, and on a transparent substrate, a first electrode (opaque electrode), an adhesive layer and An insulating layer composed of a second transparent substrate and a second electrode (opaque electrode) were formed to obtain a substrate with an electrode. The results evaluated by the above-mentioned method are shown in Table 1.

(Comparative example 2)
A substrate with an opaque electrode formed on the transparent substrate (a-1) by the same operation as in Example 1, and a transparent substrate by the same operation as in Example 2 on the transparent substrate (a-1) Substrates with a transparent electrode on which electrodes were formed were respectively produced. An adhesive sheet "Panaclean" (registered trademark) PD-R5 (Panak Co., Ltd.) is made to face the surface of the substrate with opaque electrode on which the opaque electrode is formed and the surface of the substrate with transparent electrode on which the transparent electrode is not formed. ) (Thickness: 25 μm), bonded at heating temperature: 50 ° C., applied pressure: 0.2 MPa, on a transparent substrate, a first electrode (opaque electrode), an adhesive layer and a second transparent An insulating layer composed of a substrate and a second electrode (transparent electrode) were formed to obtain a substrate with an electrode. The results evaluated by the above-mentioned method are shown in Table 1.

(Comparative example 3)
By the same operation as Comparative Example 2, a substrate with an opaque wiring electrode and a substrate with a transparent wiring electrode were produced. An adhesive sheet "Panaclean" (registered trademark) PD-R5 (Panak Co., Ltd.) is made to face the surface of the substrate with transparent electrode on which the transparent electrode is formed and the surface of the substrate with opaque electrode on which the opaque electrode is not formed. ) (Thickness: 25 μm), bonded at heating temperature: 50 ° C., applied pressure: 0.2 MPa, on a transparent substrate, a first electrode (transparent electrode), an adhesive layer and a second transparent An insulating layer composed of a substrate and a second electrode (opaque electrode) were formed to obtain a substrate with an electrode. The results evaluated by the above-mentioned method are shown in Table 1.

(Comparative example 4)
The first electrode (transparent electrode) was formed on the transparent substrate (a-1) by the same operation as the method of forming the second electrode (transparent electrode) in Example 2. However, as the exposure mask, one having a pattern of the shape shown in FIG. 4 and FIG. 5 was used. A pressure-sensitive adhesive sheet "Pana Clean" (Pana Clean) is made to face the surface of the substrate on which the first electrode (transparent electrode) is formed, on which the first electrode is not formed, and the second transparent substrate (a-1) separately prepared. From the adhesive layer and the second transparent substrate, they are bonded together under the conditions of heating temperature: 50 ° C., pressure: 0.2 MPa, through a registered trademark PD-R5 (Panak Co., Ltd.) (thickness: 25 μm) An insulating layer was formed. Furthermore, a second electrode (transparent electrode) was formed on the surface of the second transparent substrate on which the adhesive layer was not attached, in the same manner as in Example 2, to obtain a substrate with an electrode. The results evaluated by the above-mentioned method are shown in Table 1.

(Comparative example 5)
A substrate with an electrode was obtained in the same manner as in Example 1 except that the first electrode and the second electrode were formed at a heating temperature of 160 ° C. after forming the electrode pattern. The results evaluated by the above-mentioned method are shown in Table 1.

By using the method for producing a substrate with a wiring electrode of the present invention, it is possible to obtain a substrate with an electrode which is excellent in positional accuracy and can suppress moire even with a thin film transparent substrate with good yield, and has a good appearance. It is possible to provide a touch panel.

1 first transparent substrate 2 opaque electrode 3 insulating layer 4 transparent electrode 5 adhesive layer 6 second transparent substrate 7 first electrode 8 second electrode 9 mesh shape of opaque electrode X displacement amount

Claims

A method of manufacturing a substrate with an electrode having a first electrode, an insulating layer and a second electrode on a first transparent substrate having a thickness of 200 μm or less, wherein the first transparent substrate has at least one side thereof. The method includes the steps of forming an electrode, forming an insulating layer on the surface of the transparent substrate on which the first electrode is formed, and forming a second electrode on the insulating layer, Forming the second electrode and heating the second electrode at a temperature of 100.degree. C. to 150.degree. C., the first electrode and / or the second electrode being opaque. Method of manufacturing a substrate
The method according to claim 1, wherein the first transparent substrate is one selected from the group consisting of a polyethylene terephthalate film, a cycloolefin polymer film, and a polyimide film.
The method according to claim 1, wherein the first transparent substrate is a functional film.
The said insulating layer has an adhesion layer and a 2nd transparent substrate, makes the said 1st electrode and a 2nd transparent substrate mutually face, and bonds together via an adhesion layer. The manufacturing method of the board | substrate with an electrode as described in one term.
The method according to claim 4, wherein the second transparent substrate is one selected from the group consisting of a polyethylene terephthalate film, a cycloolefin polymer film, and a polyimide film.
The method according to claim 4, wherein the second transparent substrate is a functional film or a polarizing film.
The method according to any one of claims 1 to 6, wherein the line width of the opaque electrode is 1 to 10 μm.
The method according to any one of claims 1 to 6, wherein the line width of the first electrode and the second electrode is 1 to 10 μm.
The method for producing an electrode-attached substrate according to any one of claims 1 to 8, wherein the electrode-attached substrate is a member for a touch panel.