JP2018022030A - Photosensitive conducive film, and method for forming conductive pattern using the same, conductive pattern substrate and touch panel sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that in a touch panel sensor where a conductive pattern is formed by using conductive fibers such as silver, the pattern is easily visible by the reflection intrinsic to the conductive fibers.SOLUTION: A photosensitive conductive film is provided, comprising a support film, a conductive film disposed on the support film, and a photosensitive resin layer disposed on the conductive film, in which the conductive layer comprises colored conductive fibers. A method for forming a conductive pattern is provided, which uses the photosensitive conductive film. A conductive pattern substrate having the conductive pattern and a touch panel sensor including the conductive pattern substrate are also provided.SELECTED DRAWING: Figure 1

Description

  TECHNICAL FIELD The present invention relates to a photosensitive conductive film, a method for forming a conductive pattern using the same, a conductive pattern substrate, and a touch panel sensor, and in particular, electrodes of flat panel displays such as liquid crystal display elements, touch screens, solar cells, and lighting devices. The present invention relates to a photosensitive conductive film used for forming a conductive pattern used as a wiring.

  Liquid crystal display elements and touch screens are used in large electronic devices such as personal computers and televisions, as well as small electronic devices such as car navigation systems, mobile phones, and electronic dictionaries, and display devices such as OA and FA devices.

  Various types of touch panels have already been put into practical use, but in recent years, the use of capacitive touch panels has progressed. In a capacitive touch panel, when a fingertip (conductor) contacts the touch input surface, the fingertip and the conductive film are capacitively coupled to form a capacitor. For this reason, the capacitive touch panel detects the coordinates by capturing the change in charge at the contact position of the fingertip.

  In particular, the projected capacitive touch panel can detect multiple fingertips, so it has a good operability to give complex instructions. Use as an input device on a display surface in a device having a small display device such as a music player is advancing.

  In general, in a projected capacitive touch panel, a plurality of X electrodes and a plurality of Y electrodes orthogonal to the X electrodes have a two-layer structure in order to express two-dimensional coordinates based on the X and Y axes. Forming. A transparent conductive film material is used for the electrode.

  Conventionally, ITO (Indium-Tin-Oxide), indium oxide, tin oxide, and the like have been used as transparent conductive film materials because they exhibit high transmittance with respect to visible light.

  As a method for patterning a transparent conductive film, a method is generally used in which after forming a transparent conductive film, a resist pattern is formed by photolithography, and a predetermined portion of the conductive film is removed by wet etching to form a conductive pattern. In the case of an ITO and indium oxide film, a mixed liquid composed of two liquids of hydrochloric acid and ferric chloride is often used as the etching liquid.

  ITO films and tin oxide films are generally formed by sputtering, but the properties of the transparent conductive film are likely to change depending on the sputtering method, sputtering power, gas pressure, substrate temperature, type of atmospheric gas, and the like. Differences in the film quality of the transparent conductive film due to fluctuations in sputtering conditions cause variations in the etching rate when the transparent conductive film is wet-etched, and are liable to reduce product yield due to patterning defects. In addition, since the conductive pattern forming method described above has undergone a sputtering process, a resist forming process, and an etching process, the process is long and a great burden is imposed on the cost.

  Recently, in order to solve the above problems, attempts have been made to form a transparent conductive pattern using a material in place of ITO, indium oxide, tin oxide and the like. For example, Patent Document 1 below proposes a method for forming a conductive pattern using a photosensitive conductive film having a conductive film containing conductive fibers. If this technique is used, a conductive pattern can be easily formed directly on various substrates by a photolithography process.

  Furthermore, Patent Document 2 described below describes a method of forming a conductive pattern having a small step with sufficient resolution by performing an exposure process on a photosensitive conductive film twice and then developing.

International Publication No. 2010/021224 International Publication No. 2013/051516

  By using the method for forming a photosensitive conductive film disclosed in Patent Document 2, sensor electrodes (conductive patterns) of touch panels can be easily formed on various substrates by a photolithography process. However, when a sensor for a touch panel is produced using conductive fibers, particularly silver fibers, there is a problem that the conductive pattern is easily visually recognized due to reflection inherent in silver.

  As a result of intensive studies to solve the above problems, the present inventor suppresses reflection of conductive fibers by using a colorant that selectively coats conductive fibers such as silver fibers, and forms a conductive pattern that is difficult to be visually recognized. It came to invent the photosensitive conductive film which can be formed.

  The present invention is a photosensitive conductive film having a support film, a conductive film provided on the support film, and a photosensitive resin layer provided on the conductive film, wherein the conductive fibers colored by the conductive film are provided. A photosensitive conductive film is provided.

  Further, the present invention is the above photosensitive conductive film, wherein the conductive fiber is a silver fiber, the total light transmittance of the photosensitive conductive film is 89.5% or more, the reflection L * is less than 10.0, Provided is a photosensitive conductive film having a missing resolution of less than 18 μm.

  The present invention also provides a step of laminating the photosensitive conductive film so that the photosensitive resin layer is in contact with the substrate, and actinic rays in a pattern on the photosensitive layer formed by the photosensitive resin layer and the conductive film. There is provided a method for forming a conductive pattern comprising an exposing step of irradiating and a step of developing an unexposed portion of the photosensitive layer.

  In addition, the present invention includes a step of laminating the photosensitive conductive film so that the photosensitive resin layer is in contact with the substrate, and an actinic ray in a pattern on the photosensitive layer formed by the photosensitive resin layer and the conductive film. A second exposure step of irradiating at least a part or all of the unexposed portion of the photosensitive layer in the first exposure step with actinic rays in the presence of oxygen, And a step of developing the photosensitive layer after the second exposure step.

  Furthermore, this invention provides a conductive pattern board | substrate provided with a board | substrate and the conductive pattern formed on the said board | substrate by the said formation method of the conductive pattern.

  Moreover, this invention provides a touchscreen sensor provided with the said conductive pattern board | substrate.

  According to the photosensitive conductive film of the present invention, it is possible to form a conductive pattern that is difficult to visually recognize after manufacturing a touch panel sensor.

It is a schematic cross section which shows one Embodiment of the photosensitive conductive film of this invention. It is a partially notched perspective view which shows one Embodiment of the photosensitive conductive film of this invention. It is a schematic cross section for demonstrating one Embodiment of the conductive pattern formation method of this invention using the photosensitive conductive film of this invention. It is a schematic cross section for demonstrating another embodiment of the formation method of the conductive pattern of this invention. It is a model top view which shows an example of an electrostatic capacitance type touch panel sensor. It is a schematic diagram for demonstrating an example of the manufacturing method of the touchscreen sensor shown by FIG. FIG. 6 is a partial cross-sectional view taken along the line a-a ′ of the touch panel sensor shown in FIG. 5. FIG. 6 is a partial cross-sectional view taken along the line b-b ′ of the touch panel sensor shown in FIG. 5.

  Hereinafter, preferred embodiments of the present invention will be described in detail. In the present specification, “(meth) acrylate” means “acrylate” and “methacrylate” corresponding thereto. Similarly, “(meth) acryl” means “acryl” and “methacryl”, and “(meth) acryloyl” means “acryloyl” and “methacryloyl”.

<Photosensitive conductive film>
The photosensitive conductive film according to the present invention is a photosensitive conductive film having a support film, a conductive film provided on the support film, and a photosensitive resin layer provided on the conductive film. A photosensitive conductive film containing colored conductive fibers.

  In this specification, the boundary between the conductive film and the photosensitive resin layer is not necessarily clear. The conductive film only needs to have conductivity in the surface direction of the photosensitive layer containing the conductive film and the photosensitive resin layer. The conductive film may be mixed with the photosensitive resin layer. For example, the composition constituting the photosensitive resin layer may be impregnated in the conductive film, or the composition constituting the photosensitive resin layer may be present on the surface of the conductive film.

  FIG. 1 is a schematic cross-sectional view showing a preferred embodiment of the photosensitive conductive film of the present invention. A photosensitive conductive film 10 shown in FIG. 1 includes a support film 1 and a photosensitive layer 4 provided on the support film 1, and the photosensitive layer 4 includes a conductive film 2 provided on the support film, and a conductive film. 2 comprises a photosensitive resin layer 3 provided on the substrate 2.

  Hereinafter, each of the support film 1, the conductive film 2, and the photosensitive resin layer 3 constituting the photosensitive conductive film 10 will be described in detail.

  Examples of the support film 1 include polymer films having heat resistance and solvent resistance such as polyethylene terephthalate film, polyethylene film, polypropylene film, and polycarbonate film. Among these, a polyethylene terephthalate film is preferable from the viewpoint of transparency and heat resistance. In addition, since these polymer films must be removable from the photosensitive resin layer later, they may have been subjected to a surface treatment or a material that makes removal impossible. Don't be.

  Moreover, it is preferable that the thickness of the support film 1 is 5-300 micrometers, It is more preferable that it is 10-200 micrometers, It is especially preferable that it is 15-100 micrometers. The step of applying a photosensitive resin composition to form a conductive dispersion or a photosensitive resin layer 3 in order to form a conductive film 2 due to a decrease in mechanical strength, or an exposed photosensitive resin layer 3 From the viewpoint of preventing the support film from being broken in the step of peeling the support film before development, the thickness is preferably 5 μm or more, more preferably 10 μm or more, and even more preferably 15 μm or more. Moreover, in the point which is excellent in the resolution of the pattern after irradiating an active ray to a photosensitive resin layer through a support film, it is preferable that it is 300 micrometers or less, It is more preferable that it is 200 micrometers or less, It is further that it is 100 micrometers or less. preferable.

  The haze value of the support film 1 is preferably 0.01 to 5.0%, more preferably 0.01 to 3.0%, from the viewpoint of improving sensitivity and resolution. -2.0% is particularly preferred, and 0.01-1.0% is very particularly preferred. The haze value can be measured according to JIS K 7105. For example, it can be measured with a commercially available turbidimeter such as NDH-1001DP (trade name, manufactured by Nippon Denshoku Industries Co., Ltd.).

  The conductive film 2 can be used without particular limitation as long as it contains at least one colored conductive fiber.

  Examples of the conductive fibers include metal fibers such as gold, silver, and platinum, and carbon fibers such as carbon nanotubes. These can be used alone or in combination of two or more. From the viewpoint of conductivity, it is preferable to use gold fiber or silver fiber. Furthermore, silver fiber is more preferable from the viewpoint of easily adjusting the conductivity of the conductive film to be formed. A conductive fiber can be used individually or in combination of 2 or more types.

The metal fiber can be prepared by, for example, a method of reducing metal ions with a reducing agent such as NaBH ₄ or a polyol method. The carbon nanotubes may be commercial products such as Hipym single-walled carbon nanotubes from Unidim.

  The fiber diameter of the conductive fiber is preferably 1 nm to 50 nm, more preferably 2 nm to 20 nm, and particularly preferably 3 nm to 10 nm. The fiber length of the conductive fiber is preferably 1 μm to 100 μm, more preferably 2 μm to 50 μm, and particularly preferably 3 μm to 10 μm. The fiber diameter and fiber length can be measured with a scanning electron microscope.

  In the present invention, the colorant for coloring the conductive fiber can be used without particular limitation as long as it adheres or covers the conductive fiber and reduces the light reflection of the conductive fiber. In particular, those that selectively adhere to or cover conductive fibers are preferred. Examples of such a colorant include benzotriazole derivatives. Examples of the benzotriazole derivative suitably used as the colorant include tolyltriazole, 1- [N, N-bis (2-ethylhexyl) aminomethyl] benzotriazole, carboxybenzotriazole, hydroxybenzotriazole, 1-bis (2 -Hydroxyethyl) aminomethyl-5-methyl-1H-benzotriazole, 1-bis (2-hydroxyethyl) aminomethyl-4-methyl-1H-benzotriazole and the like. Such a benzotriazole derivative is particularly preferably used for coloring metal fibers such as silver fibers. A coloring agent can be used individually by 1 type or in combination of 2 or more types.

  FIG. 2 is a partially cutaway perspective view showing an embodiment of a photosensitive conductive film. As shown in FIG. 2, the conductive film 2 preferably has a network structure in which conductive fibers are in contact with each other. The conductive film 2 having such a network structure may be formed on the surface of the photosensitive resin layer 3 on the support film 1 side, but on the surface of the photosensitive layer 4 exposed when the support film 1 is peeled off. As long as conductivity is obtained in the surface direction, the conductive film 2 may be formed so that a part of the photosensitive resin layer 3 enters the conductive film 2, and the conductive film is formed on the surface layer of the photosensitive resin layer 3 on the support film 1 side. 2 may be included.

  Moreover, an organic conductor can be used for the conductive film 2 together with conductive fibers. The organic conductor can be used without any particular limitation, but it is preferable to use an organic conductor such as a polymer of a thiophene derivative or an aniline derivative. Specifically, polyethylenedioxythiophene, polyhexylthiophene, or polyaniline can be used. When using an organic conductor, the amount is preferably 10 to 80 parts by mass, and more preferably 20 to 60 parts by mass with respect to 100 parts by mass of the conductive fiber.

The thickness of the conductive film 2 varies depending on the use of the conductive pattern formed using the photosensitive conductive film of the present invention and the required conductivity, but is preferably 1 μm or less, and preferably 1 nm to 0.5 μm. Is more preferable, and it is especially preferable that it is 5 nm-0.1 micrometer.
When the thickness of the conductive film 2 is 1 μm or less, the light transmittance in the wavelength region of 450 to 650 nm is high, the pattern forming property is excellent, and it is particularly suitable for the production of a transparent electrode. In addition, the thickness of the electrically conductive film 2 points out the value measured by a scanning electron micrograph.

  The conductive film 2 is, for example, dispersed on the support film 1 with the above-described conductive fibers and organic conductors in water and / or an organic solvent, a colorant that colors the conductive fibers, and a surfactant as necessary. It can be formed by applying a conductive dispersion with an agent or the like and then drying. After drying, the conductive film 2 formed on the support film 1 may be laminated as necessary. The coating can be performed by a known method such as a roll coating method, a comma coating method, a gravure coating method, an air knife coating method, a die coating method, a bar coating method, or a spray coating method. The drying can be performed at 30 to 150 ° C. for about 1 to 30 minutes using a hot air convection dryer or the like. In the conductive film 2, the colored conductive fiber or organic conductor may coexist with the surfactant or the dispersion stabilizer.

  The content of the conductive fiber in the conductive dispersion is preferably 0.01 to 1.0% by mass, and more preferably 0.05 to 0.5% by mass. When the conductive fiber is colored by adding a colorant to the conductive dispersion, the content of the colorant in the conductive dispersion is preferably 0.01 to 2.0% by mass, and 0.03 It is more preferable to set it to -1.5 mass%. When a surfactant or dispersion stabilizer is added, the concentration in the conductive dispersion is preferably 0.01 to 0.5% by mass, more preferably 0.02 to 0.3% by mass. preferable.

  The conductive film 2 may be a combination of conductive fibers and organic conductors. In that case, a mixture of them may be applied or formed, or each may be formed by sequentially applying each of them. For example, it can be formed by applying conductive fibers and then applying and drying an organic conductor solution.

  The photosensitive resin layer 3 is formed from, for example, a photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator. Things.

  (A) As a binder polymer, for example, obtained by reaction of acrylic resin, styrene resin, epoxy resin, amide resin, amide epoxy resin, alkyd resin, phenol resin, ester resin, urethane resin, epoxy resin and (meth) acrylic acid Examples thereof include epoxy acrylate resins and acid-modified epoxy acrylate resins obtained by reaction of epoxy acrylate resins and acid anhydrides. These resins can be used alone or in combination of two or more.

  Among these, from the viewpoint of excellent alkali developability and film formability, it is preferable to use an acrylic resin, and the acrylic resin is derived from (meth) acrylic acid and a (meth) acrylic acid alkyl ester as a constituent unit. More preferably. Here, “acrylic resin” means a polymer mainly having monomer units derived from a polymerizable monomer having a (meth) acrylic group.

  The said acrylic resin can use what is manufactured by radically polymerizing the polymerizable monomer which has a (meth) acryl group. These acrylic resins can be used alone or in combination of two or more.

  Examples of the polymerizable monomer having a (meth) acryl group include acrylamide such as diacetone acrylamide, (meth) acrylic acid alkyl ester, (meth) acrylic acid tetrahydrofurfuryl ester, and (meth) acrylic acid dimethylamino. Ethyl ester, (meth) acrylic acid diethylaminoethyl ester, (meth) acrylic acid glycidyl ester, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, (Meth) acrylic acid, α-bromo (meth) acrylic acid, α-chloro (meth) acrylic acid, β-furyl (meth) acrylic acid, β-styryl (meth) acrylic acid and the like.

  The acrylic resin is substituted at the α-position or aromatic ring such as styrene, vinyltoluene, α-methylstyrene, etc., in addition to the polymerizable monomer having the (meth) acrylic group as described above. Polymerizable styrene derivatives, esters of vinyl alcohol such as acrylonitrile and vinyl-n-butyl ether, maleic acid monoester such as maleic acid, maleic anhydride, monomethyl maleate, monoethyl maleate, monoisopropyl maleate, fumaric acid One or two or more polymerizable monomers such as cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid and the like may be copolymerized.

  Examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid propyl ester, (meth) acrylic acid butyl ester, and (meth) acrylic acid. Pentyl ester, (meth) acrylic acid hexyl ester, (meth) acrylic acid heptyl ester, (meth) acrylic acid octyl ester, (meth) acrylic acid 2-ethylhexyl ester, (meth) acrylic acid nonyl ester, (meth) acrylic acid Examples include decyl ester, (meth) acrylic acid undecyl ester, and (meth) acrylic acid dodecyl ester. These can be used alone or in combination of two or more.

  Moreover, it is preferable that (A) binder polymer has a carboxyl group from a viewpoint of making alkali developability more favorable. Examples of the polymerizable monomer having a carboxyl group include (meth) acrylic acid as described above.

  (A) The ratio of the carboxyl group of the binder polymer is preferably 10 to 50% by mass, and preferably 12 to 40% by mass as the ratio of the polymerizable monomer having a carboxyl group to the total polymerizable monomer to be used. % Is more preferable, 15 to 30% by mass is particularly preferable, and 15 to 25% by mass is extremely preferable. In terms of excellent alkali developability, the content is preferably 10% by mass or more, and in terms of excellent alkali resistance, it is preferably 50% by mass or less.

  (A) The weight average molecular weight of the binder polymer is preferably 5,000 to 300,000, more preferably 20,000 to 150,000, and more preferably 30,000 to 100,000 from the viewpoint of balancing the mechanical strength and alkali developability. Particularly preferred. In terms of excellent developer resistance, the weight average molecular weight is preferably 5000 or more. Further, from the viewpoint of development time, it is preferably 300000 or less. The weight average molecular weight in the present invention is a value measured by a gel permeation chromatography method (GPC) and converted by a calibration curve prepared using standard polystyrene.

  These (A) binder polymers can be used alone or in combination of two or more. As a binder polymer in the case of using two or more types in combination, for example, two or more types of binder polymers comprising different copolymerization components, two or more types of binder polymers having different weight average molecular weights, and two or more types of binder polymers having different degrees of dispersion are used. A binder polymer is mentioned.

  In the present invention, the (A) binder polymer preferably has an acid value of 75 to 200 mgKOH / g, preferably 75 to 190 mgKOH / g, in consideration of resolution and other characteristics. More preferably, it is 75-185 mgKOH / g. When it exceeds 250 mgKOH / g, the developing solution resistance of the photocured photosensitive resin layer tends to be lowered.

Next, (B) the photopolymerizable compound having an ethylenically unsaturated bond will be described.
Examples of the photopolymerizable compound having an ethylenically unsaturated bond include a compound obtained by reacting an α, β-unsaturated carboxylic acid with a polyhydric alcohol, and an α, β-unsaturated carboxylic acid with a glycidyl group-containing compound. Compound obtained by reaction, urethane monomer such as (meth) acrylate compound having urethane bond, γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyethyl-β Examples thereof include phthalic acid compounds such as '-(meth) acryloyloxyethyl-o-phthalate and β-hydroxypropyl-β'-(meth) acryloyloxyethyl-o-phthalate, and (meth) acrylic acid alkyl esters. These may be used alone or in combination of two or more.

  Examples of the compound obtained by reacting the polyhydric alcohol with an α, β-unsaturated carboxylic acid include 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane, 2,2- Bisphenol A-based (meth) acrylate compounds such as bis (4-((meth) acryloxypolypropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolyethoxypolypropoxy) phenyl) propane, Polyethylene glycol di (meth) acrylate having 2 to 14 ethylene groups, polypropylene glycol di (meth) acrylate having 2 to 14 propylene groups, 2 to 14 ethylene groups, Polyethylene polypropylene glycol di (meth) acrylate and trimethylol having 2 to 14 numbers Propane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, trimethylolpropane diethoxytri (meth) acrylate, trimethylolpropane triethoxytri (meth) acrylate, ditrimethylolpropane Tetra (meth) acrylate, trimethylolpropane tetraethoxytri (meth) acrylate, trimethylolpropane pentaethoxytri (meth) acrylate, tetramethylolmethanetri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, number of propylene groups Is a polypropylene glycol di (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipenta Risuri Tall hexa (meth) acrylate.

Examples of the urethane monomer include a (meth) acryl monomer having a hydroxyl group at the β-position and a diisocyanate compound such as isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, and 1,6-hexamethylene diisocyanate. Addition reaction product, tris [(meth) acryloxytetraethylene glycol isocyanate] hexamethylene isocyanurate, EO-modified urethane di (meth) acrylate, EO, PO-modified urethane di (meth) acrylate, and the like.
“EO” represents ethylene oxide, and an EO-modified compound has a block structure of an ethylene oxide group. “PO” represents propylene oxide, and the PO-modified compound has a block structure of a propylene oxide group. Examples of the EO-modified urethane di (meth) acrylate include “UA-11” (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name). Examples of EO and PO-modified urethane di (meth) acrylate include “UA-13” (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.).

  (B) It is preferable that the content rate of the photopolymerizable compound which has an ethylenically unsaturated bond is 30-80 mass parts with respect to 100 mass parts of total amounts of a binder polymer and a photopolymerizable compound, and 40-70 masses. More preferably, it is a part. In terms of excellent photocurability and coating properties of the transferred conductive film (conductive film and photosensitive resin layer), it is preferably 30 parts by mass or more, and in terms of excellent storage stability when wound as a film. 80 parts by mass or less is preferable.

  Next, (C) the photopolymerization initiator will be described. (C) The photopolymerization initiator is not particularly limited as long as it matches the light wavelength of the exposure machine to be used and the wavelength necessary for function expression. For example, benzophenone, N, N′-tetra Methyl-4,4′-diaminobenzophenone (Michler ketone), N, N′-tetraethyl-4,4′-diaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1- Aromatic ketones such as (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1, 2-ethylanthraquinone, phenanthrenequinone, 2-tert -Butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone Non, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenantharaquinone, 2-methyl-1,4-naphthoquinone, 2,3 -Quinones such as dimethyl anthraquinone; benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether and benzoin phenyl ether; benzoin compounds such as benzoin, methyl benzoin and ethyl benzoin; 1,2-octanedione-1- [4- ( Oximes such as phenylthio) phenyl] -2- (O-benzoyloxime), 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] ethanone 1- (O-acetyloxime) Ester compounds; Benzies Benzyl derivatives such as dimethyl ketal; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- ( o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole 2,4,5-triarylimidazole dimers such as dimers; acridine derivatives such as 9-phenylacridine and 1,7-bis (9,9'-acridinyl) heptane; 2,4,6-trimethylbenzoyl -Phosphine oxide compounds such as diphenyl-phosphine oxide, N-phenylglycine, N-phenylglycine derivative Body, coumarin compounds, oxazole compounds and the like. Further, the substituents of the aryl groups of two 2,4,5-triarylimidazoles may be the same to give the target compound, or differently give an asymmetric compound. Moreover, you may combine a thioxanthone type compound and a tertiary amine compound like the combination of diethyl thioxanthone and dimethylaminobenzoic acid.

  Among these, an oxime ester compound or a phosphine oxide compound is preferable from the viewpoint of transparency and pattern forming ability at 10 μm or less.

  (C) It is preferable that the content rate of a photoinitiator is 0.1-20 mass parts with respect to 100 mass parts of total amounts of a binder polymer and a photopolymerizable compound, and it is 2-15 mass parts. More preferred is 5 to 12 parts by mass. In terms of excellent photosensitivity, it is preferably 0.1 parts by mass or more, and in terms of excellent internal photocurability, it is preferably 20 parts by mass or less.

  If necessary, the photosensitive resin layer 3 is provided with an adhesion imparting agent such as a silane coupling agent, a polymerization inhibitor, a plasticizer such as p-toluenesulfonamide, a colorant such as a pigment for improving visibility, Add additives such as fillers, antifoaming agents, flame retardants, stabilizers, leveling agents, release accelerators, antioxidants, fragrances, imaging agents, thermal crosslinking agents, alone or in combination of two or more. Can do. The addition amount of these additives is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the total amount of the binder polymer and the photopolymerizable compound.

  The photosensitive resin layer 3 is formed on the support film 1 on which the conductive film 2 is formed, as required, methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl. It can form by apply | coating and drying the solution of the photosensitive resin composition about 10-60 mass% of solid content melt | dissolved in solvents, such as ether, or these mixed solvents. However, in this case, the amount of the remaining organic solvent in the photosensitive resin layer after drying is preferably 2% by mass or less in order to prevent the organic solvent from diffusing in the subsequent step.

  The photosensitive resin layer 3 can be applied by a known method such as a roll coating method, a comma coating method, a gravure coating method, an air knife coating method, a die coating method, a bar coating method, or a spray coating method. After coating, drying for removing the organic solvent and the like can be performed at 70 to 150 ° C. for about 5 to 30 minutes with a hot air convection dryer or the like.

  Although the thickness of the photosensitive resin layer 3 changes with uses, it is preferable that it is 1-200 micrometers in thickness after drying, it is more preferable that it is 1-15 micrometers, and it is especially preferable that it is 1-10 micrometers. If the thickness is less than 1 μm, coating tends to be difficult, and if it exceeds 200 μm, the sensitivity due to the decrease in light transmission is insufficient, and the photocuring property of the photosensitive resin layer to be transferred tends to decrease.

In the photosensitive conductive film of the present invention, the laminate of the conductive film 2 and the photosensitive resin layer 3 has a minimum light transmittance in a wavelength region of 450 to 650 nm when the total film thickness of both layers is 1 to 10 μm. Is preferably 80% or more, and more preferably 85% or more. When the conductive film and the photosensitive resin layer satisfy such conditions, it is easy to increase the brightness in a display panel or the like.
The photosensitive conductive film of the present invention preferably has a total light transmittance of 89.5% or more. In this specification, the total light transmittance of the photosensitive conductive film means the total light transmittance of the laminate including the conductive layer and the cured resin layer after the photosensitive resin layer is cured. The total light transmittance is measured by, for example, laminating a photosensitive conductive film on a transparent substrate with the photosensitive resin layer and the transparent substrate facing each other, and then curing the photosensitive resin layer by exposure or the like. After forming the cured layer, the support film is removed to obtain a laminate for evaluation having a transparent substrate / resin cured layer / conductive layer, and the total light transmittance of the laminate can be measured using a haze meter. .
The photosensitive conductive film of the present invention preferably has a reflection L * of less than 10.0. In this specification, the reflection L * of the photosensitive conductive film means the reflection L * of the laminate including the conductive layer and the cured resin layer after the photosensitive resin layer is cured. The measurement of the reflection L * can be performed, for example, by preparing a laminate for evaluation in the same manner as described above and measuring the reflection L * of the laminate with a spectrocolorimeter.
Further, the photosensitive conductive film of the present invention preferably has a missing resolution of less than 18 μm, more preferably less than 16 μm, and even more preferably 15 μm or less. In the present specification, the loss of the photosensitive conductive film means that the photosensitive layer including the conductive layer and the photosensitive resin layer of the photosensitive conductive film is exposed and developed by using a line / space test pattern as a mask. Means the minimum line width value of the test pattern in which the conductive layer between and is fully developed.

  In the photosensitive conductive film of this invention, a protective film can be laminated | stacked so that the surface on the opposite side to the support film 1 side of the photosensitive resin layer 3 may be contacted as needed.

  As the protective film, for example, a polymer film having heat resistance and solvent resistance such as a polyethylene terephthalate film, a polypropylene film, and a polyethylene film can be used. Moreover, you may use the polymer film similar to the above-mentioned support body film as a protective film.

  The adhesive force between the protective film and the photosensitive resin layer 3 is such that the conductive film 2 and the photosensitive resin layer 3 and the support film 1 have an adhesive force so that the protective film is easily peeled from the photosensitive resin layer. Is preferably smaller.

Moreover, it is preferable that the number of fish eyes with a diameter of 80 micrometers or more contained in a protective film is 5 pieces / m < ² > or less. “Fish eye” means that when a material is melted by heat, kneaded, extruded, biaxially stretched, casting method, etc., foreign materials, undissolved materials, oxidized degradation products, etc. It is taken in.

  The thickness of the protective film is preferably 1 to 100 μm, more preferably 5 to 50 μm, further preferably 5 to 30 μm, and particularly preferably 15 to 30 μm. When the thickness of the protective film is less than 1 μm, the protective film tends to be broken during lamination, and when it exceeds 100 μm, the price tends to increase.

  The photosensitive conductive film may further have layers such as an adhesive layer and a gas barrier layer on the support film.

  The photosensitive conductive film can be stored, for example, in the form of a flat plate as it is or in the form of a roll wound around a cylindrical core. In addition, it is preferable to wind up in this case so that a support film may become outermost.

  Moreover, when the photosensitive conductive film does not have a protective film, this photosensitive conductive film can be stored as it is in the form of a flat plate.

  The core is not particularly limited as long as it is conventionally used. For example, plastic such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, ABS resin (acrylonitrile-butadiene-styrene copolymer) Is mentioned. Moreover, it is preferable to install an end face separator on the end face of the photosensitive conductive film wound up in a roll shape from the viewpoint of end face protection, and in addition, it is preferable to install a moisture-proof end face separator from the viewpoint of edge fusion resistance. Moreover, when packing a photosensitive conductive film, it is preferable to wrap and wrap in a black sheet with small moisture permeability.

<Method for forming conductive pattern>
As shown in FIG. 3, a photosensitive conductive film 10 having a support film 1, a conductive film 2, and a photosensitive resin layer 3 is laminated on a substrate 20 so that the photosensitive resin layer 3 is in contact with the substrate (FIG. 3). 3 (a)), and then, the photosensitive layer 4 formed of the conductive film 2 and the photosensitive resin layer 3 is irradiated with an actinic ray L in a pattern through the mask pattern 5 ((b) of FIG. 3). The conductive pattern 2a (conductive film 2) is formed by removing the uncured part (unexposed part) by development ((c) of FIG. 3). The conductive pattern 2 a thus obtained has the thickness of the cured resin layer 3 b in addition to the thickness of the conductive film 2. These thicknesses become a step Hb with the substrate, and if this step is large, it becomes difficult to obtain the smoothness required for a display or the like. Moreover, since a conductive pattern will be easily visually recognized if a level | step difference is large, what is necessary is just to use properly with the method shown in the following FIG.

  As shown in the embodiment shown in FIG. 4, first, a photosensitive conductive film 10 having a support film 1, a conductive film 2, and a photosensitive resin layer 3 is placed on a substrate 20 so that the photosensitive resin layer 3 is in contact with the substrate. After the first exposure step (FIG. 4 (b)) in which a predetermined portion of the photosensitive layer 4 having the support film 1 is laminated and then irradiated with an actinic ray (FIG. 4 (b)), the support film 1 is laminated. After peeling, in the presence of oxygen, a second exposure step (FIG. 4C) is performed in which a part or all of the unexposed portion in the first exposure step of the photosensitive layer 4 is irradiated with actinic rays. It is preferable. In addition, in the aspect shown in FIG. 4, the exposed part in the 1st exposure process is simultaneously irradiating the actinic ray with the unexposed part in the 1st exposure process of a photosensitive layer. According to the method of developing after performing the first and second exposure steps, the resin is cured in the region where the conductive film 2 having a predetermined conductive pattern is exposed in the first and second exposure steps after development. A cured resin layer that does not have the conductive film 2 is formed on the portion remaining on the layer and removed in the development step (FIG. 4D). Thus, by providing the resin cured layer 3a not having the conductive film together with the conductive pattern on the substrate 20, the conductive having the conductive pattern having a small step Ha compared to the case where only the conductive pattern is provided on the substrate. The pattern substrate 42 can be obtained.

  Examples of the substrate include a glass substrate, a plastic substrate such as polycarbonate, polyethylene terephthalate, and the like. The substrate preferably has a minimum light transmittance of 80% or more in a wavelength region of 450 to 650 nm.

The laminating step is performed, for example, by a method of laminating the photosensitive conductive film by removing the protective film, if any, and then pressing the photosensitive resin layer side against the substrate while heating. In addition, it is preferable to laminate | stack this operation under pressure reduction from the viewpoint of adhesiveness and followability. When laminating the photosensitive conductive film, it is preferable to heat the photosensitive resin layer and / or the substrate to 70 to 130 ° C., and the pressure bonding pressure is about 0.1 to 1.0 MPa (about 1 to 10 kgf / cm ² ). However, these conditions are not particularly limited. In addition, if the photosensitive resin layer is heated to 70 to 130 ° C. as described above, it is not necessary to pre-heat the substrate in advance, but it is also possible to perform pre-heat treatment of the substrate in order to further improve the lamination property. .

  As an exposure method in the first exposure step of irradiating a predetermined portion of the photosensitive resin layer on the substrate with the support film attached thereto, the active light is imaged through a negative or positive mask pattern called artwork. An irradiation method (mask exposure method) can be mentioned. As the active light source, a known light source, for example, a carbon arc lamp, a mercury vapor arc lamp, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, or the like that effectively emits ultraviolet light, visible light, or the like is used. Further, an Ar ion laser, a semiconductor laser, or the like that effectively emits ultraviolet light, visible light, or the like is also used. Furthermore, what effectively radiates | emits visible light, such as a photographic flood light bulb and a solar lamp, is also used. Alternatively, a method of irradiating actinic rays in an image shape by a direct drawing method using a laser exposure method or the like may be employed.

The exposure amount of the first exposure step may vary depending on the composition of the device or a photosensitive resin composition to be used, preferably from ^{5mJ / cm 2 ~1000mJ / cm 2} , more preferably 10mJ ^/ cm 2 ~200mJ / Cm ² . In terms of excellent photocurability, it is preferably 10 mJ / cm ² or more, and in terms of resolution, it is preferably 200 mJ / cm ² or less.

  As a light source in the second exposure step of irradiating actinic rays in the presence of oxygen after peeling off the support film, known light sources such as carbon arc lamps, mercury vapor arc lamps, ultrahigh pressure mercury lamps, high pressure mercury lamps, xenon A lamp or the like that effectively emits ultraviolet light, visible light, or the like is used. Further, an Ar ion laser, a semiconductor laser, or the like that effectively emits ultraviolet light, visible light, or the like is also used. Furthermore, the thing which radiates | emits visible light effectively, such as a flood bulb for photography, a solar lamp, is also used

The exposure amount in the second exposure step may vary depending on the composition of the device or a photosensitive resin composition to be used, preferably from ^{5mJ / cm 2 ~1000mJ / cm 2} , more preferably 10mJ ^/ cm 2 ~200mJ / Cm ² . In terms of excellent photocurability, it is preferably 10 mJ / cm ² or more, and in terms of work efficiency, it is preferably 200 mJ / cm ² or less. The amount of exposure in the second exposure step is such that the reactive species generated from the initiator by exposure is deactivated by oxygen from the surface by removing the support film and exposing, and excessively This exposure is not preferable because it sufficiently cures.
The atmosphere in which the exposure in the second exposure step is performed requires the presence of oxygen, and exposure in the air is preferable. It does not matter even if the oxygen concentration is increased.

  In the development process of the present embodiment, the sufficiently uncured surface portion of the photosensitive resin layer exposed in the second exposure process in which actinic rays are irradiated after peeling off the support film is removed. Specifically, the surface portion of the photosensitive resin layer that is not sufficiently cured, that is, the surface layer including the conductive film is removed by wet development. Thereby, the conductive film having a predetermined pattern remains on the cured resin layer in the areas exposed in the first and second exposure processes, and the cured resin having no conductive film in the portion removed in the development process. A layer pattern is formed. Therefore, in the development process, the entire photosensitive resin layer is removed from the part that is not exposed in both the first and second exposure processes.

  The wet development is performed by a known method such as spraying, rocking immersion, brushing, or scraping, using a developer corresponding to a photosensitive resin such as an alkaline aqueous solution, an aqueous developer, or an organic solvent developer. .

  As the developing solution, a safe and stable solution having good operability such as an alkaline aqueous solution is used. Examples of the base of the alkaline aqueous solution include alkali hydroxides such as lithium, sodium, or potassium hydroxide, alkali carbonates such as lithium, sodium, potassium, or ammonium carbonate or bicarbonate, potassium phosphate, and phosphoric acid. Alkali metal phosphates such as sodium and alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate are used.

  Moreover, as alkaline aqueous solution used for image development, 0.1-5 mass% sodium carbonate aqueous solution, 0.1-5 mass% potassium carbonate aqueous solution, 0.1-5 mass% sodium hydroxide aqueous solution, 0.1-5 mass % Sodium tetraborate aqueous solution and the like are preferable. Moreover, it is preferable to make pH of the alkaline aqueous solution used for image development into the range of 9-11, and the temperature is adjusted according to the developability of the photosensitive resin layer. In the alkaline aqueous solution, a surfactant, an antifoaming agent, a small amount of an organic solvent for accelerating development, and the like may be mixed.

Further, an aqueous developer composed of water or an aqueous alkali solution and one or more organic solvents can be used. Here, as the base contained in the alkaline aqueous solution, in addition to the above-mentioned bases, for example, borax, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-1 , 3-propanediol, 1,3-diaminopropanol-2, morpholine.
Examples of the organic solvent include 3-acetone alcohol, acetone, ethyl acetate, alkoxyethanol having an alkoxy group having 1 to 4 carbon atoms, ethyl alcohol, isopropyl alcohol, butyl alcohol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono Butyl ether is mentioned. These are used alone or in combination of two or more.

  The aqueous developer preferably has an organic solvent concentration of 2 to 90% by mass, and the temperature can be adjusted according to the developability. Furthermore, the pH of the aqueous developer is preferably as low as possible within a range where the resist can be sufficiently developed, preferably pH 8-12, more preferably pH 9-10. In addition, a small amount of a surfactant, an antifoaming agent, or the like can be added to the aqueous developer.

  Examples of the organic solvent developer include 1,1,1-trichloroethane, N-methylpyrrolidone, N, N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone. These organic solvents preferably add water in the range of 1 to 20% by mass in order to prevent ignition.

  Two or more of the above-described developing solutions may be used in combination as necessary.

  Examples of the development method include a dip method, a battle method, a spray method, brushing, and slapping. Among these, it is preferable to use a high-pressure spray system from the viewpoint of improving the resolution.

In the method for forming a conductive pattern of the present embodiment, the conductive pattern may be further cured by performing exposure at about 0.2 to 10 J / cm ² or heating at about 60 to 250 ° C. as necessary after development. Good.

<Conductive pattern substrate>
The conductive pattern substrate of the present invention comprises a substrate and a conductive pattern formed by the conductive pattern forming method of the present invention using the photosensitive conductive film of the present invention. That is, the conductive pattern is obtained by patterning the conductive film of the photosensitive conductive film of the present invention by the conductive pattern forming method of the present invention. Between the board | substrate and the layer of the conductive pattern formed with the formation method of the conductive pattern of this invention, the resin cured layer which resin of the photosensitive resin layer of this invention hardened | cured exists.
From the viewpoint that it can be effectively used as a transparent electrode, the surface resistivity of the conductive film or conductive pattern is preferably 2000Ω / □ or less, more preferably 1000Ω / □ or less, and particularly preferably 500Ω / □ or less. preferable. The surface resistivity can be adjusted by, for example, the concentration of the conductive fiber or organic conductor dispersion or the coating amount.

  In the conductive pattern substrate of the present invention, the minimum light transmittance in the wavelength region of 450 to 650 nm is preferably 80% or more, and more preferably 85% or more.

<Touch panel sensor>
A touch panel sensor according to the present invention includes the conductive pattern substrate.

  FIG. 5 is a schematic top view illustrating an example of a capacitive touch panel sensor. The touch panel sensor shown in FIG. 5 has a touch screen 102 for detecting a touch position on one surface of a transparent substrate 101, and a transparent electrode 103 that detects a change in capacitance in this region and uses it as an X position coordinate; A transparent electrode 104 having Y position coordinates is provided. Each of the transparent electrodes 103 and 104 having the X and Y position coordinates includes a lead wire 105 for connecting to a driver element circuit for controlling an electric signal as a touch panel, and the lead wire 105 and the transparent electrodes 103 and 104. A connection electrode 106 for connecting the two is disposed. Further, a connection terminal 107 connected to the driver element circuit is disposed at the end of the lead-out wiring 105 opposite to the connection electrode 106.

  FIG. 6 is a schematic view showing an example of a method for manufacturing the touch panel sensor shown in FIG. In the present embodiment, the transparent electrodes 103 and 104 are formed by the conductive pattern forming method according to the present invention. First, as shown in FIG. 6A, a transparent electrode (X position coordinate) 103 is formed on a transparent substrate 101. Specifically, the photosensitive conductive film 10 is laminated so that the photosensitive resin layer 3 is in contact with the transparent substrate 101. The transferred photosensitive layer 4 (the conductive film 2 and the photosensitive resin layer 3) is irradiated with an actinic ray in a desired shape through a light-shielding mask (first exposure step). Thereafter, the light shielding mask is removed, the support film is further peeled off, and the photosensitive layer 4 is irradiated with actinic rays (second exposure step). By performing development after the exposure step, the conductive film 2 is removed together with the photosensitive resin layer 3 that is not sufficiently cured, and a conductive pattern 2a is formed. The transparent electrode 103 for detecting the X position coordinate is formed by the conductive pattern 2a (FIG. 6B). FIG. 6B is a schematic cross-sectional view taken along the line II of FIG. By forming the transparent electrode 103 by the method for forming a conductive pattern according to the present invention, the transparent electrode 103 with a small step can be provided.

  Subsequently, a transparent electrode (Y position coordinate) 104 is formed as shown in FIG. A new photosensitive conductive film 10 is further laminated on the substrate 101 including the transparent electrode 103 formed by the above-described process, and the transparent electrode 104 for detecting the Y position coordinate is formed by the same operation as described above (see FIG. 6 (d)). FIG.6 (d) is a schematic cross section of the II-II cut surface of FIG.6 (c). By forming the transparent electrode 104 by the conductive pattern forming method according to the present invention, even when the transparent electrode 104 is formed on the transparent electrode 103, reduction in aesthetics due to stepping or entrainment of bubbles is sufficiently suppressed. A touch panel sensor with high smoothness can be created.

  Next, on the surface of the transparent substrate 101, a lead wire 105 for connecting to an external circuit and a connection electrode 106 for connecting the lead wire and the transparent electrodes 103 and 104 are formed. In FIG. 6, the lead line 105 and the connection electrode 106 are shown to be formed after the formation of the transparent electrodes 103 and 104, but they may be formed simultaneously with the formation of the transparent electrodes. The lead line 105 can be formed at the same time as the connection electrode 106 is formed by screen printing using a conductive paste material containing flaky silver, for example.

  7 and 8 are partial cross-sectional views along a-a 'and b-b' shown in FIG. 5, respectively. These indicate the intersections of the transparent electrodes at the XY position coordinates. As shown in FIGS. 7 and 8, the transparent electrode is formed by the conductive pattern forming method according to the present invention, so that a touch panel sensor with small steps and high smoothness can be obtained.

  Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited thereto.

The components (B) and (C) used in Examples and Comparative Examples are as follows.
<(B) component>
・ Ditrimethylolpropane tetraacrylate (T-1420, manufactured by Nippon Kayaku Co., Ltd.)

<(C) component>
2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (Irgacure-TPO, manufactured by BASF Japan Ltd.)

<Others>
-Octamethylcyclotetrasiloxane (SH-30, manufactured by Toray Dow Corning Co., Ltd.) as a leveling agent
・ Methyl ethyl ketone (made by Tonen Chemical Co., Ltd.) as a solvent
-2-methacryloxyethyl acid phosphate (P-1M, manufactured by Kyoeisha Chemical Co., Ltd.) as an adhesion promoter
-2,2'-methylenebis (4-ethyl-6-tert-butylphenol) as a polymerization inhibitor (AW-500, manufactured by Kawaguchi Chemical Co., Ltd.)

Production Example 1 <Preparation of conductive dispersion (coating liquid for forming conductive film (silver fiber dispersion))>
[Preparation of silver fiber by polyol method]
In a 2000 ml three-necked flask, 500 ml of ethylene glycol was placed and heated to 160 ° C. with an oil bath while stirring with a magnetic stirrer under a nitrogen atmosphere. A solution prepared by dissolving ₂ mg of PtCl ₂ separately prepared in 50 ml of ethylene glycol was added dropwise thereto. After 4 to 5 minutes, a solution of 5 g of AgNO ₃ dissolved in 300 ml of ethylene glycol and a solution of 5 g of polyvinylpyrrolidone (manufactured by Wako Pure Chemical Industries, Ltd.) having a weight average molecular weight of about 40,000 in 150 ml of ethylene glycol were prepared. The solution was dropped from each dropping funnel in 1 minute, and then stirred at 160 ° C. for 60 minutes.

  The reaction solution was allowed to stand at 30 ° C. or lower, diluted 10 times with acetone, centrifuged at 2000 rpm for 20 minutes with a centrifuge, and the supernatant was decanted. Acetone was added to the precipitate, stirred, and then centrifuged under the same conditions as described above, and acetone was decanted. Then, it centrifuged twice similarly using distilled water, and obtained the silver fiber. When the obtained silver fiber was observed with an optical microscope, the fiber diameter (diameter) was about 17 nm, and the fiber length was about 30 μm.

[Preparation of silver fiber dispersion]
In pure water, 0.2% by mass of the silver fiber obtained above, 0.1% by mass of dodecylpentaethylene glycol (surfactant), and the components shown in Table 4 (1) for coloring the silver fiber are listed. 4 was dispersed so as to have the concentration shown in (1).
The components that color the silver fibers shown in (1) of Table 4 are as follows.
A mixture of 1-bis (2-hydroxyethyl) aminomethyl-5-methyl-1H benzotriazole and 1-bis (2-hydroxyethyl) aminomethyl-4-methyl-1H-benzotriazole (trade name: VERZONE TT-250A , Manufactured by Yamato Kasei Co., Ltd.), a benzotriazole derivative (trade name: VERZONE SF-310, manufactured by Yamato Chemical Co., Ltd.).
Each of the above was blended to obtain a silver fiber dispersion.

Production Example 2 <Preparation of Component Solution (A)>
[Preparation of binder polymer solution (A1)]
A flask equipped with a stirrer, reflux condenser, inert gas inlet and thermometer was charged with (1) shown in Table 1, heated to 80 ° C. in a nitrogen gas atmosphere, and the reaction temperature was 80 ° C. ± 2 While maintaining the temperature, (2) shown in Table 1 was added dropwise uniformly over 4 hours. After dropping (2), stirring was continued at 80 ° C. ± 2 ° C. for 6 hours to obtain a binder polymer solution (solid content 50 mass%) (A1) having a weight average molecular weight of about 42,000. The acid value of (A1) was 196 mgKOH / g.

[Preparation of binder polymer solution (A2)]
A flask equipped with a stirrer, reflux condenser, inert gas inlet and thermometer was charged with (1) shown in Table 2, heated to 80 ° C. in a nitrogen gas atmosphere, and the reaction temperature was 80 ° C. ± 2 While maintaining the temperature, (2) shown in Table 2 was uniformly added dropwise over 4 hours. After dropping (2), stirring was continued at 80 ° C. ± 2 ° C. for 6 hours to obtain a binder polymer solution (solid content 50 mass%) (A2) having a weight average molecular weight of about 45,000. The acid value of (A2) was 78 mgKOH / g.

[Preparation of binder polymer solution (A3)]
A flask equipped with a stirrer, reflux condenser, inert gas inlet and thermometer was charged with (1) shown in Table 2, heated to 80 ° C. in a nitrogen gas atmosphere, and the reaction temperature was 80 ° C. ± 2 While maintaining the temperature, (2) shown in Table 3 was uniformly added dropwise over 4 hours. After dropwise addition of (2), stirring was continued at 80 ° C. ± 2 ° C. for 6 hours to obtain a binder polymer solution (solid content 50 mass%) (A3) having a weight average molecular weight of about 40,000. The acid value of (A3) was 176 mgKOH / g.

  In the said manufacture example, the weight average molecular weight and the acid value were measured with the following method.

(1) Weight average molecular weight The weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC), and was derived by conversion using a standard polystyrene calibration curve. The GPC conditions are shown below.
GPC conditions Pump: Hitachi L-6000 type (manufactured by Hitachi, Ltd., product name)
Column: Gelpack GL-R420, Gelpack GL-R430, Gelpack GL-R440 (above, manufactured by Hitachi Chemical Co., Ltd., product name)
Eluent: Tetrahydrofuran Measurement temperature: 40 ° C
Flow rate: 2.05 mL / min Detector: Hitachi L-3300 type RI (manufactured by Hitachi, Ltd., product name)

(2) Acid value The acid value was measured as follows. First, the binder polymer solution prepared above was heated at 130 ° C. for 1 hour to remove volatile components, thereby obtaining a solid content. Then, after precisely weighing 1 g of the polymer whose acid value is to be measured, the precisely weighed polymer was put into an Erlenmeyer flask, 30 g of acetone was added to this polymer, and this was uniformly dissolved. Next, an appropriate amount of an indicator, phenolphthalein, was added to the solution, and titration was performed using a 0.1N aqueous KOH solution. And the acid value was computed by following Formula.
Acid value = 10 × Vf × 56.1 / (Wp × I)
(In the formula, Vf represents the titration amount (mL) of the KOH aqueous solution, Wp represents the mass (g) of the measured resin solution, and I represents the proportion (mass%) of the nonvolatile content in the measured resin solution. )

Example 1 <Production of photosensitive conductive film>
[Preparation of conductive film (conductive film of photosensitive conductive film)]
The silver fiber dispersion obtained above was uniformly applied at 25 g / m ² on a 50 μm-thick polyethylene terephthalate film (PET film, manufactured by Teijin Ltd., trade name “G2-50”) as a support film, It dried for 3 minutes with a 100 degreeC hot-air convection dryer, and formed the electrically conductive film. The film thickness after drying of the conductive film was about 0.1 μm, and the sheet resistance value measured by EC-80P manufactured by Napson Corporation was 50 ± 10Ω / □.

[Preparation of photosensitive resin composition solution]
The materials shown in Table 4 (2) are blended in the blending amounts (parts by mass) shown in Table 4 (2), and methyl ethyl ketone is added as a solvent in such an amount that the volatile component concentration becomes 30% by mass, and a stirrer is used. For 15 minutes to prepare a photosensitive resin composition solution for a photosensitive conductive film. As the component (A), the above (A2) was used.
In addition, the compounding quantity of (A) component in (4) of Table 4 is a mass part of solid content except a solvent.

[Preparation of photosensitive conductive film]
The photosensitive resin composition solution obtained above was uniformly applied onto a 50 μm-thick polyethylene terephthalate film on which a conductive film was formed with the conductive film obtained above, and 10 times with a hot air convection dryer at 100 ° C. The photosensitive resin layer was formed by drying for a minute. Thereafter, the photosensitive resin layer was covered with a protective film made of polyethylene (manufactured by Tamapoly Co., Ltd., trade name “NF-13”) to obtain a photosensitive conductive film. In addition, the film thickness after drying of the photosensitive resin layer was 5 micrometers.

Example 2 <Production of photosensitive conductive film>
[Preparation of conductive film (conductive film of photosensitive conductive film)]
A conductive film was formed in the same manner as the conductive film of Example 1 except that the colorant in the silver fiber dispersion was changed to SF-310. In addition, it was 50 ohms / square when the sheet resistance value of the electrically conductive film was measured by EC-80P made from Napson Corporation.

[Preparation of photosensitive conductive film]
A photosensitive conductive film was produced in the same manner as in Example 1 except that the photosensitive resin composition solution obtained above was used. In addition, the film thickness after drying of the photosensitive resin layer was 5 micrometers.

Example 3 <Production of photosensitive conductive film>
[Preparation of conductive film (conductive film of photosensitive conductive film)]
A conductive film was formed in the same manner as in the production of the conductive film of Example 1, except that the colorant in the silver fiber dispersion was changed to SF-310 and the concentration was changed to 0.08% by mass. In addition, it was 50 ohms / square when the sheet resistance value of the electrically conductive film was measured by EC-80P made from Napson Corporation.

[Preparation of photosensitive conductive film]
A photosensitive conductive film was produced in the same manner as in Example 1 except that the photosensitive resin composition solution obtained above was used. In addition, the film thickness after drying of the photosensitive resin layer was 5 micrometers.

Example 4 <Preparation of photosensitive conductive film>
[Preparation of conductive film (conductive film of photosensitive conductive film)]
A conductive film was formed in the same manner as in the production of the conductive film of Example 1, except that the colorant in the silver fiber dispersion was changed to SF-310 and the concentration was changed to 0.12% by mass. In addition, it was 50 ohms / square when the sheet resistance value of the electrically conductive film was measured by EC-80P made from Napson Corporation.

[Preparation of photosensitive conductive film]
A photosensitive conductive film was produced in the same manner as in Example 1 except that the photosensitive resin composition solution obtained above was used. In addition, the film thickness after drying of the photosensitive resin layer was 5 micrometers.

Comparative Example 1 <Production of photosensitive conductive film>
[Preparation of conductive film (conductive film of photosensitive conductive film)]
A conductive film was formed in the same manner as in the production of the conductive film of Example 1 except that no colorant was added to the silver fiber dispersion. In addition, it was 50 ohms / square when the sheet resistance value of the electrically conductive film was measured by EC-80P made from Napson Corporation.

[Preparation of photosensitive conductive film]
A photosensitive conductive film was produced in the same manner as in Example 1 except that the photosensitive resin composition solution obtained above was used. In addition, the film thickness after drying of the photosensitive resin layer was 5 micrometers.

<Measurement of reflection L *>
The reflection L * was evaluated as a visibility evaluation standard. While peeling the protective film of the photosensitive conductive film obtained above on a polycarbonate substrate having a thickness of 1 mm, the photosensitive resin layer was opposed to the PET film, and the conditions were 110 ° C., 0.6 m / min, and 0.4 MPa. Laminated with. After laminating, when the PET film is cooled and the temperature of the substrate reaches 23 ° C., 1000 mJ using an exposure machine (trade name “EXM-1201”, manufactured by Oak Manufacturing Co., Ltd.) having a high-pressure mercury lamp from the support film side. Light was irradiated at an exposure amount of / cm ² . After the light irradiation, the support film was peeled off to obtain a laminate for evaluation comprising a polycarbonate substrate / resin cured layer / conductive layer.
Next, the reflection L * of the evaluation laminate was measured with a spectrocolorimeter CM-5 (manufactured by Konica Minolta, Inc.). The smaller the value, the smaller the reflected light and the harder it is to see. The results are shown in (3) of Table 4.

<Measurement of total light transmittance>
With respect to said laminated body for evaluation, the total light transmittance of the laminated body for evaluation was measured using the haze meter (made by Nippon Denshoku Industries Co., Ltd., brand name "NDH-5000"). The results are shown in (3) of Table 4.

<Formation of conductive pattern>
While peeling the protective film of the photosensitive conductive film obtained above on the surface of a 125 μm-thick PET film (trade name “Cosmo Shine-A300” manufactured by Toyobo Co., Ltd.), the photosensitive resin layer was made into a PET film. It was made to oppose and it laminated on the conditions of 110 degreeC, 0.6 m / min, and 0.4 MPa.
After lamination, when the PET film is cooled and the temperature of the substrate reaches 23 ° C., a step tablet for investigating photosensitive characteristics (S / T; L / S = x / 400, x = 6 to 47) is covered and supported. Using an exposure machine (trade name “EXM-1201”, manufactured by Oak Manufacturing Co., Ltd.) having a high-pressure mercury lamp from the film side, light irradiation was performed at an exposure amount of 40 mJ / cm ² . After the light irradiation, the support film was peeled off, and the light was irradiated at an exposure amount of 100 mJ / cm ² with the mask removed.

Next, development was performed by spraying a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 40 seconds. Further, an exposure dose of 1 J / cm ² was irradiated with a UV exposure machine.
Through the above operation, the conductive pattern shown in FIG. 2E was formed on the PET film.
As an evaluation of missing resolution, the line width of a line / space (L / 400 μm) pattern was measured. The narrower the line width, the higher the resolution. The results are shown in (3) of Table 4.
The evaluation of sensitivity was performed by applying a tester to each step number of the step tablet and reading the highest number of steps that can be conducted. The results are shown in (3) of Table 4.

  As shown in Table 4, in each of Examples 1 to 4, the reflection L * is low compared to Comparative Example 1, and by using the photosensitive conductive film of the present invention, it is difficult to visually recognize the touch panel sensor after fabrication. It can be seen that a pattern can be formed.

  DESCRIPTION OF SYMBOLS 1 ... Support film, 2 ... Conductive film, 2a ... Conductive pattern, 3 ... Photosensitive resin layer, 3a, 3b ... Resin hardened layer, 4 ... Photosensitive layer, 5 ... Mask pattern, 10, 12 ... Photosensitive conductive film, 20 ... Board, 40, 42 ... Conductive pattern board, 101 ... Transparent board, 102 ... Touch screen, 103 ... Transparent electrode (X position coordinate), 104 ... Transparent electrode (Y position coordinate), 105 ... Lead-out wiring, 106 ... Connection electrode 107 Connection terminals.

Claims (6)

  A photosensitive conductive film having a support film, a conductive film provided on the support film, and a photosensitive resin layer provided on the conductive film, wherein the conductive layer contains conductive fibers colored. Conductive film.   2. The photosensitive conductive film according to claim 1, wherein the conductive fiber is a silver fiber, and the photosensitive conductive film has a total light transmittance of 89.5% or more, a reflection L * of less than 10.0, and an omission. A photosensitive conductive film having a resolution of less than 18 μm.   A step of laminating the photosensitive conductive film according to claim 1 or 2 so that the photosensitive resin layer is in contact with the substrate, and an active ray in a pattern on the photosensitive layer formed by the photosensitive resin layer and the conductive film. A method for forming a conductive pattern, comprising: an exposure step of irradiating the substrate; and a step of developing an unexposed portion of the photosensitive layer. A step of laminating the photosensitive conductive film according to claim 1 or 2 so that the photosensitive resin layer is in contact with the substrate, and an active ray in a pattern on the photosensitive layer formed by the photosensitive resin layer and the conductive film. A second exposure step of irradiating at least a part or all of the unexposed portion of the photosensitive layer in the first exposure step with actinic rays in the presence of oxygen.
And a step of developing the photosensitive layer after the second exposure step.   A conductive pattern substrate comprising: a substrate; and a conductive pattern formed on the substrate by the conductive pattern forming method according to claim 3.   A touch panel sensor comprising the conductive pattern substrate according to claim 5.

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