JPWO2013115310A1 - Substrate with transparent conductive film and touch panel - Google Patents

Abstract

Provided is a substrate with a transparent conductive film that is excellent in adhesion over time between a transparent conductive film using metal nanowires and a transparent substrate. A substrate 4 with a transparent conductive film obtained by laminating a transparent conductive film 3 containing metal nanowires on a transparent substrate 1 through a primer layer 2 having a surface wetting tension of 30 mN / m or more as defined in JIS K6768: 1999. It is. The primer layer 2 preferably includes 90% by weight or more of a resin component including a cured product of a curable resin and a thermoplastic resin. The curable resin is preferably an ionizing radiation curable resin, more preferably an ionizing radiation curable organic-inorganic hybrid resin. The ratio of the cured product of the curable resin to the thermoplastic resin in the resin component is 50% to 90% by weight of the cured product of the curable resin, and 10% to 50% by weight of the thermoplastic resin. It is preferable.

Description

  The present invention relates to a substrate with a transparent conductive film that can be used for various flat panel displays, transparent electrodes such as a touch panel, an antistatic layer, an electromagnetic wave shielding layer, and the like, and a touch panel using the substrate as an electrode.

  As a transparent conductive film, a metal oxide film obtained by sputtering a metal oxide such as indium tin oxide (ITO) or a conductive film made of a conductive polymer is widely known.

  However, the metal oxide film is fragile and easily broken by physical stress such as bending. Therefore, it is difficult to apply to a product group on the premise that physical stress is applied. Further, in order to impart high conductivity, it is necessary to increase the processing temperature for vapor deposition and annealing. Therefore, application to a plastic substrate is difficult. Furthermore, it is difficult to adhere to plastic substrates such as polycarbonate. Therefore, it is difficult to appropriately form on a plastic substrate.

  A conductive film made of a conductive polymer is inferior in transparency and conductivity as compared with a metal oxide film, and is difficult to apply to transmission applications.

  As a solution to the above problems, a transparent conductive film formed from metal nanowires has been proposed (Patent Document 1).

Special table 2009-505358

  The transparent conductive film of Patent Document 1 exhibits high conductivity and transparency equivalent to or higher than that of a metal oxide film when metal nanowires are in contact with each other in the film, and has the above disadvantages of the metal oxide film. There is nothing.

  However, the transparent conductive film of Patent Document 1 has a problem that the adhesiveness deteriorates with time even if the initial adhesiveness with the transparent substrate is good.

  In one aspect of the present invention, a transparent conductive film using metal nanowires and a substrate with a transparent conductive film excellent in adhesiveness over time of a transparent substrate, and a touch panel configured using the substrate as an electrode are provided.

  The present inventors have found that the interposition of a primer layer having a wetting tension of a predetermined value or more in between can improve the adhesion with time of a transparent conductive film containing metal nanowires to a transparent substrate, and completed the present invention. . Thereby, the stable continuous use of electronic devices, such as a touch panel, is realizable.

The substrate with a transparent conductive film of the present invention is obtained by laminating a transparent conductive film containing metal nanowires on a transparent substrate via a primer layer having a surface wetting tension of 30 mN / m or more as defined in JIS K6768: 1999. Features.
The touch panel of the present invention is characterized by using the substrate with a transparent conductive film of the present invention as an electrode.

The present invention includes the following aspects.
(1) A primer layer can be comprised including the resin part containing the hardened | cured material of curable resin. In this case, the resin content can be 90% by weight or more in the primer layer.
(2) An ionizing radiation curable resin can be used as the curable resin, and an ionizing radiation curable organic-inorganic hybrid resin can be used as the ionizing radiation curable resin.

(3) The resin component in the primer layer can further contain a thermoplastic resin together with a cured product of the curable resin. In this case, the content of the resin can be set to 50% by weight or more and 90% by weight or less of a cured curable resin, and 10% by weight or more and 50% by weight or less of a thermoplastic resin.
(4) A primer layer can also be comprised including particle | grains with a resin part. In this case, particles having an average particle diameter of 3 μm or more and 10 μm or less can be used. Moreover, content of particle | grains can be 0.02 weight part or more and 1 weight part or less with respect to 100 weight part of resin parts.

(5) The primer layer may contain low refractive index fine particles having an average particle diameter of 1 nm to 200 nm.

In the substrate with a transparent conductive film of the present invention, the primer layer having a wetting tension of a predetermined value or more is interposed between the transparent conductive film using the metal nanowire and the transparent substrate. Not only the initial adhesiveness but also the temporal adhesion can be improved.
Since the touchscreen of this invention uses the base material with a transparent conductive film of this invention for an electrode, it can implement | achieve the stable continuous use.

FIG. 1 is a cross-sectional view showing an example of a substrate with a transparent conductive film of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Transparent base material, 2 ... Primer layer, 3 ... Transparent conductive film, 4 ... Base material with a transparent conductive film.

  First, an example of the substrate with a transparent conductive film of the present invention will be described. As shown in FIG. 1, the substrate 4 with a transparent conductive film of this example is configured by laminating a transparent conductive film 3 on a transparent substrate 1 via a primer layer 2.

  Examples of the transparent substrate 1 include plastic films (for example, various films such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethylene, polypropylene, polystyrene, triacetyl cellulose, and acrylic) and glass. Among plastic films, a polyethylene terephthalate film that has been stretched, in particular biaxially stretched, is preferred because of its excellent mechanical strength and dimensional stability. Although the thickness of the transparent base material 1 changes with uses, generally it is about 25-500 micrometers, Preferably it is 50-200 micrometers.

  The transparent conductive film 3 includes at least metal nanowires. Any metal nanowire can be used, and its production means is not particularly limited, and known means such as a liquid phase method and a gas phase method can be used. As a method for producing Ag nanowires, the above-mentioned Patent Document 1, as a method for producing Au nanowires, JP 2006-233252A, as a method for producing Cu nanowires, JP 2002-266007, and as a method for producing Co nanowires are described. Examples include the method described in Japanese Unexamined Patent Publication No. 2004-148771.

  Examples of the metal constituting the metal nanowire include elemental metals, alloys, and metal oxides. At least one cross-sectional dimension of the metal nanowire is preferably 200 nm or less from the viewpoint of transparency, and preferably 10 nm or more from the viewpoint of conductivity. In addition, the metal nanowire preferably has an aspect ratio of 10 or more, more preferably 50 or more, and even more preferably 100 or more, from the viewpoint of conductivity.

  It is preferable that the transparent conductive film 3 further includes a resin component that binds the metal nanowire together with the metal nanowire. As such a resin component, the resin component illustrated in the explanation column of the primer layer 2 described later can be used. Among these, it is preferable to use a cured product of an ionizing radiation curable resin or a thermosetting resin.

  The content ratio of metal nanowires in the total solid content forming the transparent conductive film 3 is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and further preferably 0.5% by mass or more. The content is preferably 90% by mass or less, more preferably 30% by mass or less, and still more preferably 10% by mass or less. The refractive index of the transparent conductive film 3 is usually about 1.45 or more and 1.52 or less.

  A primer layer 2 is interposed between the transparent substrate 1 and the transparent conductive film 3. The primer layer 2 has a surface wetting tension (JIS K6768: 1999) adjusted to 30 mN / m or more, preferably 32 mN / m or more. By laminating the transparent conductive film 3 with the transparent base material 1 through the primer layer 2 having a surface wetting tension of 30 mN / m or more, the initial adhesiveness between the transparent base material 1 and the transparent conductive film 3 as well as the temporal adhesion The inventors have found that this can be enhanced.

  It is preferable that most of the primer layer 2 is composed of a resin component. Specifically, the resin content in the primer layer 2 is preferably 90% by weight or more, more preferably 95% by weight or more. When the resin content is reduced, it is difficult to adjust the surface wetting tension to 30 mN / m or more while maintaining the coating layer strength of the primer layer 2 to be high to some extent. On the other hand, when the primer layer 2 is formed so that the resin content is 90% by weight or more, the surface wetting tension of the primer layer 2 can be easily adjusted.

  The resin component referred to in this example includes a cured product of a curable resin and a thermoplastic resin. In addition, the cured product in this example refers to curing of a polymerization initiator, a polymerization accelerator (such as an ultraviolet sensitizer), and a curing agent necessary for curing the curable resin together with a curable resin as a curing main agent. It is used in the concept including auxiliary agents.

  The resin component constituting the primer layer 2 includes at least a cured product of a curable resin. When the primer layer 2 is formed including the cured product of the curable resin, it is easy to adjust the surface wetting tension to a predetermined value or more compared to the case where the primer layer 2 is formed only by the thermoplastic resin without including the primer layer 2. .

  Examples of curable resins include polyester resins, acrylic resins, acrylic urethane resins, urethane resins, epoxy resins, polycarbonate resins, melamine resins, phenol resins, silicone resins, acrylate resins (polyester acrylate resins). Resin (polyurethane acrylate resin, epoxy acrylate resin, etc.), etc., such as resin (thermosetting resin, ionizing radiation curable resin) capable of forming a cured product (cured film) by heat or ionizing radiation. A curable resin can also be used. Among these, an ionizing radiation curable resin is preferable from the viewpoint of improving the temporal adhesion between the transparent substrate 1 and the transparent conductive film 3 and capable of forming a cured product having excellent surface hardness.

  As the ionizing radiation curable resin, those that are cross-linked and cured by irradiation with ionizing radiation (ultraviolet rays or electron beams) are used. As such, it is possible to use one or a mixture of two or more of a photocationic polymerizable resin capable of photocationic polymerization, a photopolymerizable prepolymer capable of photoradical polymerization, or a photopolymerizable monomer. it can.

  Examples of the cationic photopolymerizable resin include epoxy resins such as bisphenol epoxy resins, novolac epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins, and vinyl ether resins.

  Examples of the photopolymerizable prepolymer include polyester (meth) acrylate, epoxy (meth) acrylate, urethane (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, and melamine (meth) acrylate ( And (meth) acrylates.

  Examples of the photopolymerizable monomer include styrene monomers such as styrene and α-methylstyrene, (meth) acrylates such as methyl (meth) acrylate and butyl (meth) acrylate, and unsaturated carboxylic acids such as (meth) acrylamide. Substituted amino alcohol esters of unsaturated acids such as acid amides, (meth) acrylic acid-2- (N, N-diethylamino) ethyl, (meth) acrylic acid-2- (N, N-dibenzylamino) ethyl, Ethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, isocyanuric acid triacrylate (for example, tris- (2-hydroxyethyl) -isocyanuric acid ester (meth) acrylate), 3 -Phenoxy-2 2 in a molecule such as propanoyl acrylate, polyfunctional compounds such as 1,6-bis (3-acryloxy-2-hydroxypropyl) -hexyl ether, and trimethylolpropane trithioglycolate, pentaerythritol tetrathioglycolate Examples thereof include polythiol compounds having one or more thiol groups.

In addition to the above-mentioned photocationic polymerizable resin, photopolymerizable prepolymer or photopolymerizable monomer, the ionizing radiation curable resin is a curing aid such as a photopolymerization initiator or an ultraviolet sensitizer when cured by ultraviolet irradiation. It is preferable to contain an agent.
Photopolymerization initiators include photo radical polymerization initiators such as acetophenones, benzophenones, Michler's ketone, benzoin, benzylmethyl ketal, benzoylbenzoate, α-acyloxime esters, thioxanthones, onium salts, sulfonate esters, and organic metals Examples include photocationic polymerization initiators such as complexes. Examples of the ultraviolet sensitizer include n-butylamine, triethylamine, and tri-n-butylphosphine.

  In addition, it is particularly preferable to use an ionizing radiation curable organic-inorganic hybrid resin from the viewpoint of further improving the temporal adhesion between the transparent substrate 1 and the transparent conductive film 3. Unlike traditional composites typified by glass fiber reinforced plastic (FRP), ionizing radiation curable organic-inorganic hybrid resins (hereinafter sometimes simply referred to as “organic-inorganic hybrid resins”) are organic and inorganic. The mixture is intimately mixed, and the dispersion state is at or close to the molecular level. By irradiation with ionizing radiation, the inorganic component and the organic component react to form a film.

  Examples of the inorganic component in the organic-inorganic hybrid resin include metal oxides such as silica and titania, and silica is preferable.

  Examples of the silica include reactive silica in which a photosensitive group having photopolymerization reactivity is introduced on the surface. For example, with respect to the powdery silica or colloidal silica which is the base, the groups represented by the following general formulas (1) and (2), hydrolyzable silyl group, and polymerizable unsaturated group are included in the molecule. The compound which the compound which has has chemically couple | bonded through the silyloxy group by the hydrolysis reaction of a hydrolyzable silyl group can be used.

(In the formula, X is selected from NH, an oxygen atom and a sulfur atom, and Y is selected from an oxygen atom and a sulfur atom. However, when X is an oxygen atom, Y is a sulfur atom.)

  Examples of the hydrolyzable silyl group include a carboxylylate silyl group such as an alkoxylyl group and an acetoxysilyl group, a halogenated silyl group such as a chlorosilyl group, an aminosilyl group, an oxime silyl group, and a hydridosilyl group. Examples of the polymerizable unsaturated group include acryloyloxy group, methacryloyloxy group, vinyl group, propenyl group, butadienyl group, styryl group, ethynyl group, cinnamoyl group, malate group, and acrylamide group.

  As the reactive silica, those having an average particle diameter of preferably 1 nm or more, preferably 100 nm or less, more preferably 10 nm or less are used. By using reactive silica having an average particle diameter in a predetermined range, it is easy to maintain transparency when the primer layer 2 is formed.

  The content of the inorganic component in the organic-inorganic hybrid resin is preferably 10% by weight or more, more preferably 20% by weight, preferably 65% by weight or less, more preferably 40% by weight or less. By setting the content of the inorganic component to 10% by weight or more, the adhesion between the transparent substrate 1 and the transparent conductive film 3 can be easily improved. Moreover, it becomes easy to maintain transparency when it is set as the primer layer 2 by setting it as 65 weight% or less.

  The organic component in the organic-inorganic hybrid resin is a compound having a polymerizable unsaturated group polymerizable with the inorganic component (preferably reactive silica) (for example, having two or more polymerizable unsaturated groups in the molecule). And polyunsaturated organic compounds or unit price unsaturated organic compounds having one polymerizable unsaturated group in the molecule).

  Examples of the polyunsaturated organic compound include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, glycerol di (meth) acrylate, glycerol tri (meth) acrylate, and 1,4-butanediol di (meth) acrylate. 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dicyclopentanyl di (meth) acrylate, pentaerythritol tri (meth) acrylate, penta Erythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, ditrimethylolpropane tetra ( Data) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate.

  Examples of monounsaturated organic compounds include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, and lauryl (meth) ) Acrylate, stearyl (meth) acrylate, allyl (meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) Acrylate, glycerol (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (2-ethoxy ester) Xy) ethyl (meth) acrylate, butoxyethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, 2- Examples include methoxypropyl (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, and polypropylene glycol (meth) acrylate. .

The resin component constituting the primer layer 2 preferably further includes a thermoplastic resin together with a cured product of the curable resin. By including a thermoplastic resin in the resin component constituting the primer layer 2, the temporal adhesion between the transparent substrate 1 and the transparent conductive film 3 can be made more than when the primer layer 2 is formed only by a cured product of a curable resin. It can be made even better.
Examples of the thermoplastic resin include cellulose resin, acetal resin, vinyl resin, polyethylene resin, polystyrene resin, polypropylene resin, polyamide resin, polyimide resin, and fluorine resin. Among these, it is preferable to use a thermoplastic resin having a glass transition temperature of 70 ° C. or less from the viewpoint of improving the temporal adhesion between the transparent substrate 1 and the transparent conductive film 3.

  When the resin component constituting the primer layer 2 is formed of a cured product of an ionizing radiation curable resin and a thermoplastic resin, the weight ratio between the two is preferably 50 wt% to 90 wt% and the latter is 10 wt%. % To 50% by weight, more preferably 60% to 80% by weight for the former and 20% to 40% by weight for the latter. By setting it as such a weight ratio, while being able to make favorable temporal adhesiveness easily, it can prevent that the intensity | strength of the primer layer 2 falls more than necessary.

  The resin component constituting the primer layer 2 may be composed of only a resin having a hydrophilic group, or may be composed of a mixture of a resin having no hydrophilic group and a resin having a hydrophilic group. Moreover, you may comprise with what mixed the particle | grains which have a hydrophilic group on the surface in these. In addition, examples of the hydrophilic group herein include at least polyalkylene oxide, hydroxyl group, carboxyl group, sulfonyl group, phosphate, amino group, isocyanate group, glycidyl group, alkoxysilyl group, ammonium salt, various metal salts, and the like. 1 type or more is mentioned. By setting it as such a structure, it becomes easy to adjust the wetting tension on the surface of a primer layer more than predetermined value.

  The primer layer 2 preferably contains particles together with the resin component. By including particles in the primer layer 2, the temporal adhesion between the transparent substrate 1 and the transparent conductive film 3 can be made better. In particular, when the cured layer of the organic-inorganic hybrid resin is included in the primer layer 2, when the organic-inorganic hybrid resin is cured, the primer layer 2 has an effect of pushing up the particles to the surface of the primer layer 2. can do.

  Examples of the particles include inorganic particles (for example, silica, alumina, talc, clay, calcium carbonate, magnesium carbonate, barium sulfate, aluminum hydroxide, titanium dioxide, zirconium oxide, etc.) and resin particles (for example, acrylic resin particles, silicone resin). Particles, nylon resin particles, styrene resin particles, polyethylene resin particles, benzoguanamine resin particles, urethane resin particles, etc.).

  The average particle diameter of the particles is preferably 3 μm or more, more preferably 4 μm or more, preferably 10 μm or less, more preferably 8 μm or less. By setting the average particle diameter to 3 μm or more, the temporal adhesion between the transparent substrate 1 and the transparent conductive film 3 can be made better. By setting the thickness to 10 μm or less, it is possible to prevent a decrease in transparency. In addition, the average particle diameter in this case means what was calculated by the Coulter counter method.

  The particles having an average particle diameter of preferably 3 μm or more and 10 μm or less are preferably contained in an amount of 0.02 parts by weight or more and 1 part by weight or less with respect to 100 parts by weight of the resin in the primer layer 2, more preferably 0 0.03 parts by weight or more and 0.5 parts by weight or less.

  The refractive index of the primer layer 2 is preferably adjusted so that the difference from the transparent conductive film 3 is within 0.05. By setting the refractive index of the primer layer 2 in such a range, the pattern can be made inconspicuous when the transparent conductive film 3 is patterned by etching.

  In order to adjust the refractive index of the primer layer 2 to the above-mentioned range, the primer layer 2 preferably contains low refractive index fine particles. Here, the low refractive index fine particles preferably have an average particle diameter of 1 nm or more and 200 nm or less from the viewpoints of particle aggregation prevention and transparency. In addition, the average particle diameter in this case means what was calculated by the dynamic light scattering method.

  Examples of the low refractive index fine particles include magnesium fluoride, silsesquioxane, silica, polystyrene, calcium fluoride, cryolite and the like. Of these low refractive index fine particles, those having a hollow structure or mesoporous structure are preferred in that they have a lower refractive index.

  Such low refractive index fine particles are preferably contained in an amount of 0.5 to 700 parts by weight with respect to 100 parts by weight of the resin in the primer layer 2.

  In addition, it is preferable that the primer layer 2 of this example does not contain excessive leveling agents (silicone type, fluorine type, acrylic type, etc.). When the leveling agent is excessively included in the primer layer 2, it is difficult to adjust the surface wetting tension to 30 mN / m or more.

  The thickness of the primer layer 2 is not particularly limited and can be adjusted depending on the particles used. For example, when the primer layer 2 contains particles having an average particle diameter of 3 μm or more and 10 μm or less, the thickness of the primer layer 2 is usually about 2 μm or more and 9 μm or less. In addition, when the primer layer 2 includes low refractive index fine particles having an average particle diameter of 1 nm or more and 200 nm or less, the thickness of the primer layer 2 in the case of not having a high refractive index layer described later is usually about 0.5 μm or more and 3 μm or less. The thickness of the primer layer 2 in the case of having a high refractive index layer to be described later is usually about 10 nm to 100 nm.

  An overcoat layer for protecting the conductive film 3 may be provided on the transparent conductive film 3. The overcoat layer may be a resin film formed from various resins or an inorganic film formed from an inorganic substance.

  Between the transparent base material 1 and the primer layer 3, you may have a high refractive index layer. The refractive index of the high refractive index layer is preferably about 0.2 to 0.3 higher than the refractive index of the primer layer 2. By having such a high refractive index layer, the pattern can be made inconspicuous when the transparent conductive film 3 is patterned by etching.

  The high refractive index layer is formed from a binder resin and high refractive index fine particles. As the binder resin, the same resin as that of the primer layer 2 can be used. The high refractive index fine particles preferably have an average particle diameter of 1 nm or more and 200 nm or less from the viewpoints of particle aggregation prevention and transparency. In addition, the average particle diameter in this case means what was calculated by the dynamic light scattering method.

  The high refractive index fine particles preferably have a refractive index of 1.6 or more, and examples thereof include oxide particles selected from titanium, aluminum, cerium, yttrium, zirconium, niobium, and antimony. Such high refractive index fine particles are preferably contained in an amount of 5 to 300 parts by weight with respect to 100 parts by weight of the binder resin in the high refractive index layer.

  The thickness of the high refractive index layer is preferably 10 nm or more and 100 nm or less.

  The transparent conductive film 3, the primer layer 2 and the high refractive index layer of this example are coated with a composition (coating liquid) containing each film and the resin component constituting each layer, dried, and irradiated with ionizing radiation as necessary. And can be formed by forming a coating film.

  The surface of the transparent conductive film 3 may be subjected to pressure treatment. By subjecting the surface of the transparent conductive film 3 to pressure treatment, the transparent conductive film 3 that has been made uneven by the metal nanowires protruding from the surface can be planarized. Examples of the pressure treatment include means for passing the substrate 4 with a transparent conductive film through a hot roll having an outer peripheral surface formed on a smooth surface or pressing the substrate 4 with a hot press having a pressure surface formed on a smooth surface.

  The substrate 4 with a transparent conductive film of this example can be used for various flat panel displays, transparent electrodes such as touch panels, antistatic layers, electromagnetic wave shielding layers, and the like. Hereinafter, application examples to the touch panel will be described.

  Examples of the touch panel include a resistive touch panel and a capacitive touch panel.

A resistive touch panel has an upper electrode having a transparent conductive layer on one side of a transparent substrate, a lower electrode having a transparent conductive layer on one side of the transparent substrate, and a transparent conductive layer between the upper electrode and the lower electrode. It consists of a basic structure that is arranged with a spacer so as to face each other.
In such a resistive film type touch panel, the above-mentioned substrate 4 with a transparent conductive film can be used as an upper electrode or a lower electrode.

The capacitive touch panel can be divided into a surface type and a projected type.
The surface mold has a basic configuration in which a transparent conductive film and a protective layer are provided on one surface of a substrate, and electrodes disposed at four corners.
The substrate 4 with a transparent conductive film described above can be used as a substrate and a transparent conductive film that constitute such a surface-type capacitive touch panel.

The projection type is a conductive element group formed along a second direction intersecting the X-axis trace, which is a conductive element group formed along a predetermined first direction on a transparent substrate. The basic configuration includes a Y-axis trace, an insulating layer disposed at least at the intersection of the X-axis trace and the Y-axis trace, and a connection wiring to an external lead-out line.
The touch panel of the present invention is configured to have the above-described substrate 4 with a transparent conductive film on a transparent substrate in such a projected capacitive touch panel.

  Hereinafter, the present invention will be described in more detail with examples that further embody the embodiment of the present invention. In this example, “parts” and “%” are based on weight unless otherwise specified.

1. Preparation of Coating Solution for Transparent Conductive Film Silver nanowires prepared according to the paper “Materials Chemistry and Physics vol. 114 p333-338“ Preparation of Ag nanorods with high yield by polyol process ”” were used as metal nanowires. This silver nanowire has an average diameter on the short side of 50 nm and an aspect ratio of about 100.
Next, a dispersion liquid in which silver nanowires were dispersed at 3.0% using IPA as a dispersion medium was prepared. Next, 28.53 parts of a silicone resin (Mitsubishi Chemical Corporation: MS51) was dissolved in 53.82 parts of IPA to prepare a mother liquor. Next, 15.0 parts by mass of the dispersion was added to the mother liquor and mixed well, then 2.65 parts of 0.1H nitric acid was added and mixed well, and the mixture was stirred and mixed in a constant temperature atmosphere at 25 ° C. for 1 hour. A coating solution for transparent conductive film having a solid content of 15% containing 3% was prepared.

2. Preparation of substrate with transparent conductive film [Example 1]
On one surface of a 125 μm thick transparent polyester film (Cosmo Shine A4350: Toyobo Co., Ltd.), a primer layer coating solution a having the following formulation was applied, dried and irradiated with ultraviolet rays to form a primer layer having a thickness of 3 μm. The wetting tension on the surface of the primer layer was 32 mN / m. Subsequently, the said transparent conductive layer coating liquid was apply | coated and dried on the primer layer, the 0.3-micrometer-thick transparent conductive film was formed, and the base material with a transparent conductive film was obtained.

<Primer layer coating solution a>
・ 140 parts of photopolymerizable prepolymer (ionizing radiation curable organic-inorganic hybrid resin)
(Desolite 7503: JSR Corporation, solid content 50%, inorganic component 38%)
70 parts of thermoplastic resin (Acridic A166: DIC, solid content 45%, glass transition temperature 49 ° C.)
-Photopolymerization initiator 2.2 parts (Irgacure 651: Ciba Japan)
-0.25 parts of acrylic resin particles (average particle size: 5.8 μm, coefficient of variation 7.8%)
・ 230 parts of diluted solvent

[Example 2]
A substrate with a transparent conductive film was obtained in the same manner as in Example 1 except that the amount of the acrylic resin particles added to the primer layer coating liquid a was changed to 0.05 part. The wetting tension on the surface of the primer layer was 32 mN / m.

[Example 3]
A substrate with a transparent conductive film was obtained in the same manner as in Example 1 except that the primer layer coating solution a was changed to the following primer layer coating solution b. The wetting tension on the primer layer surface was 33 mN / m.

<Primer layer coating solution b>
17 parts of photopolymerizable prepolymer (ionizing radiation curable resin) (beam set 575: Arakawa Chemical Industries, solid content 100%)
Photopolymerizable monomer (isocyanuric acid triacrylate) 3 parts (NK ester A9300: Shin-Nakamura Chemical Co., Ltd., solid content 100%)
-Photopolymerization initiator (Irgacure 651) 0.4 part-Diluting solvent 30 parts

[Example 4]
A substrate with a transparent conductive film was obtained in the same manner as in Example 1 except that the primer layer coating solution a was changed to the following primer layer coating solution c. The wetting tension on the primer layer surface was 33 mN / m.

<Primer layer coating solution c>
・ 35 parts of photopolymerizable prepolymer (beam set 575) 35 parts of thermoplastic resin (Acridic A166) 1 part of photopolymerization initiator (Irgacure 651) 120 parts of diluting solvent

[Example 5]
A substrate with a transparent conductive film was obtained in the same manner as in Example 1 except that the primer layer coating solution a was changed to the following primer layer coating solution d. The wetting tension on the surface of the primer layer was 32 mN / m.

<Primer layer coating solution d>
・ 68 parts of photopolymerizable prepolymer (Desolite 7503) 2 parts of photopolymerization initiator (Irgacure 651) 72 parts of diluting solvent

[Comparative Example 1]
A substrate with a transparent conductive film was obtained in the same manner as in Example 1 except that the primer layer coating solution a was changed to the following primer layer coating solution e. The wetting tension on the primer layer surface was 22.6 mN / m or less.

<Primer layer coating solution e>
・ Photopolymerizable prepolymer (beam set 575) 10 parts ・ Photopolymerizable monomer (polyethylene glycol diacrylate) 5 parts (component: polyethylene glycol diacrylate)
(NK ester A-1000: Shin-Nakamura Chemical Co., Ltd., solid content 100%)
・ Silicon-based leveling agent 0.02 parts (polyether-modified dimethylpolysiloxane)
(BYK331: Big Chemie, solid content 100%)
・ Photopolymerization initiator (Irgacure 651) 0.5 part ・ Dilute solvent 23 parts

[Comparative Example 2]
A substrate with a transparent conductive film was obtained in the same manner as in Example 1 except that the primer layer coating solution a was changed to the following primer layer coating solution f. The wetting tension on the primer layer surface was 22.6 mN / m or less.

<Primer layer coating solution f>
-15 parts of a mixture of a photopolymerizable prepolymer and a leveling agent (Unidic 17-824-9: DIC, solid content 80%)
-Photopolymerization initiator (Irgacure 651) 0.4 part-Diluting solvent 30 parts

3. Evaluation of Adhesiveness For the substrate with a transparent conductive film obtained in each example, initial adhesiveness and temporal adhesiveness were evaluated based on the cross-cut tape method in JIS K5400: 1990. As a result, the case where the transparent conductive film was not peeled at all was designated as “◎”, the case where less than 10% of the area was peeled off was designated as “◯”, and the case where almost 100% of the area was peeled off was designated as “x”. The results are shown in Table 1.
In addition, about time-dependent adhesiveness, the base material with a transparent conductive film obtained by each example was evaluated after leaving to stand on condition of 60 degreeC and 90% RH for 500 hours.

  Since the base material with a transparent conductive film of Examples 1-5 had the wetting tension of the primer layer surface of 30 mN / m or more, it was excellent in the initial stage adhesiveness and temporal adhesiveness of a transparent conductive film. In particular, the substrate with a transparent conductive film in each of Examples 1, 2 and 4 was compared with Examples 3 and 5 in that an ionizing radiation curable resin (ionizing radiation curable organic-inorganic hybrid resin was used in the primer layer). Including) and a thermoplastic resin, the adhesion with time was extremely excellent. Especially, the base material with a transparent conductive film of Examples 1 and 2 is particles having an average particle diameter in the range of 3 to 10 μm together with the ionizing radiation curable organic-inorganic hybrid resin and the thermoplastic resin as compared with Example 4. In the primer layer, the adhesion over time was even better.

  On the other hand, in the substrates with transparent conductive films of Comparative Examples 1 and 2, the wetting tension on the primer layer surface was less than 30 mN / m. As a result, although the initial adhesion of the transparent conductive film was excellent, the adhesion over time was not satisfactory.

Claims (10)

  A substrate with a transparent conductive film, in which a transparent conductive film containing metal nanowires is laminated on a transparent substrate through a primer layer having a surface wetting tension of 30 mN / m or more as defined in JIS K6768: 1999.   2. The substrate with a transparent conductive film according to claim 1, wherein the primer layer includes a resin component containing a cured product of a curable resin.   The substrate with a transparent conductive film according to claim 2, wherein an ionizing radiation curable resin is used as the curable resin.   The substrate with a transparent conductive film according to claim 3, wherein an ionizing radiation curable organic-inorganic hybrid resin is used as the ionizing radiation curable resin.   The substrate with a transparent conductive film according to any one of claims 2 to 4, wherein the resin component further contains a thermoplastic resin.   6. The substrate with a transparent conductive film according to claim 5, wherein a content ratio in the resin component is a cured product of a curable resin: 50% by weight to 90% by weight, and a thermoplastic resin: 10% by weight to 50% by weight. The base material with a transparent conductive film characterized by being the following.   The substrate with a transparent conductive film according to any one of claims 2 to 6, wherein the primer layer further comprises particles having an average particle diameter of 3 µm to 10 µm. Substrate with film.   8. The substrate with a transparent conductive film according to claim 7, wherein the content with respect to 100 parts by weight of the resin component is particles: 0.02 parts by weight or more and 1 part by weight or less.   The substrate with a transparent conductive film according to any one of claims 2 to 8, wherein the primer layer further comprises low refractive index fine particles having an average particle diameter of 1 nm to 200 nm. A substrate with a transparent conductive film.   The touch panel comprised using the base material with a transparent conductive film in any one of Claims 1-9 for an electrode.

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