JP2016133862A - Conductive laminate and touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive laminate that gives good visibility and has a less visible patterning when used for a liquid crystal display or the like.SOLUTION: The conductive laminate has a portion X having a transparent conductive layer and a portion Y having no transparent conductive layer on at least one surface A of a transparent substrate, and satisfies the following conditions (1) to (5): (1) λ is an integer; (2) RXrepresents a reflectance (%) in the portion X measured on the surface A side at a wavelength is λ nm; (3) RYrepresents a reflectance (%) in the portion Y measured on the surface A side at a wavelength of λ nm; (4) ΔR(%) is defined by ΔR=|RX-RY|; and (5) an expression described below is satisfied.SELECTED DRAWING: None

Description

  The present invention relates to a conductive laminate in which a transparent conductive layer is laminated on a transparent substrate. In particular, when used as a patterned electrode film such as a capacitive touch panel, the difference in optical properties between the portion having the transparent conductive layer and the removed portion is small, and therefore relates to a conductive laminate that can improve visibility. It is.

  A conductive laminate obtained by laminating a transparent thin film with low resistance on a transparent substrate is used for applications utilizing the conductivity, such as a liquid crystal display or an electroluminescence (sometimes abbreviated as EL) display. Such flat panel displays and transparent electrodes for resistive touch panels are widely used in electrical and electronic fields.

  In recent years, an increasing number of cases where a capacitive touch panel is mounted on a mobile device such as a mobile phone or a portable music terminal. Such a capacitive touch panel has a configuration in which a dielectric layer is laminated on a patterned conductor, and is touched with a finger or the like to be grounded via the capacitance of the human body. At this time, a change occurs in the resistance value between the patterning electrode and the ground point, and the position input is recognized. However, when a conventional conductive laminate is used, the difference in optical characteristics between the portion having the transparent conductive layer and the removed portion is large, so that the patterning is conspicuous, and when placed on the front surface of a display body such as a liquid crystal display There was a problem that visibility was lowered.

  In order to improve the transmittance or color of the conductive laminate, a method of using light interference by laminating layers having different refractive indexes used in antireflection processing or the like has been proposed. That is, a method of using optical interference by providing layers having different refractive indexes between the conductive laminate and the base material has been proposed (Patent Documents 1 to 3).

Japanese Patent Laid-Open No. 11-286066 Japanese Patent No. 3626624 JP 2006-346878 A

However, although the conductive laminates described in Patent Documents 1 to 3 can improve the visibility as the conductive laminate, when the transparent conductive layer is patterned, there are portions with and without a transparent conductive film. It is not considered to reduce the difference in the optical characteristics of the film, and the patterned part becomes conspicuous.

  That is, in view of the above-mentioned conventional problems, the object of the present invention is to reduce the difference in optical characteristics between the portion having the transparent conductive layer and the removed portion, thereby improving the visibility when used in a liquid crystal display or the like. An object of the present invention is to provide a conductive laminate that is good and does not show remarkable patterning.

This invention is made | formed in view of the above situations, Comprising: The electrically conductive laminated body which could solve said subject consists of the structure of the following [1]-[8].
[1] Conductive laminate having a portion X having a transparent conductive layer and a portion Y not having a transparent conductive layer on at least one surface A of the transparent substrate, and satisfying the following conditions (1) to (5) body.

  (1) λ: integer.

(2) RX _λ : reflectivity (%) at the portion X measured from the surface A side when the wavelength is _λ nm.

(3) RY _λ : reflectivity (%) in the portion Y measured from the surface A side when the wavelength is _λ nm.

(4) ΔR _λ = | RX _λ -RY _λ | (%)

  [2] The conductive laminate according to [1], wherein the haze is 1.0% or less.

  [3] The conductive laminate according to [1] or [2] above, wherein a color difference adjusting layer is provided between the surface A and the transparent conductive layer.

[4] The color difference adjusting layer comprises a curable composition containing a cured resin component (i), metal oxide particles (ii), and an initiator (iii).
The cured resin component (i) has a urethane structure, a molecular weight of 1,000 to 300,000, a compound (B1) having a polymerizable functional group, a structure that expresses intermolecular force, and a molecular weight. The conductive laminate according to [3], comprising a compound (B2) having a polymerizable functional group at 200 to 50,000. (However, the compound (B1) and the compound (B2) are not the same compound.)
[5] The cured resin component (i) contains less than 80 parts by weight of the total of the compound (B1) and the compound (B2) with respect to 100 parts by weight of the dry weight of the component (i). The conductive laminate according to [4].

  [6] The conductive laminate according to any one of [1] to [5], wherein the transparent substrate has an anti-blocking layer on a surface B opposite to the surface A.

[7] The conductive laminate according to any one of [1] to [6], wherein the transparent conductive layer is a crystalline layer containing indium oxide, and the thickness of the transparent conductive layer is 5 to 50 nm. .
[8] A touch panel including the conductive laminate according to any one of [1] to [7].

Here, the left side of requirement (5) of [1] is expressed as Σ (ΔR _λ ), and is treated as such.

  The conductive laminate of the present invention has a configuration in which a transparent conductive thin film layer is laminated on a transparent substrate, and when the transparent conductive layer is patterned, the portion X having the transparent conductive layer and the portion Y having no structure are optical. Since the difference in characteristics is small, the patterning of the transparent conductive layer is inconspicuous even if it is arranged on the front surface of a display body such as a liquid crystal display, so that a reduction in visibility can be suppressed.

5 is a graph showing optical characteristics of RX _λ and RX _{λ according} to an embodiment of the present invention.

The conductive laminate of the present invention has a configuration in which a transparent conductive thin film layer is laminated on a transparent substrate. Hereinafter, each layer will be described in detail.
(Transparent substrate)
Examples of the transparent substrate used in the conductive laminate of the present invention include polyester films such as polycarbonate films, polyethylene terephthalate, and polyethylene naphthalate; cellulose films such as diacetyl cellulose and triacetyl cellulose; acrylics such as polymethyl methacrylate. Examples thereof include a substrate made of a transparent polymer such as a base film. The transparent substrate used in the conductive laminate of the present invention includes polystyrene, acrylonitrile / styrene copolymer and other styrene films; polyvinyl chloride, polyethylene, polypropylene, polyolefin having a cyclic or norbornene structure, ethylene / propylene Examples also include substrates made of transparent polymers such as olefin films such as copolymers; amide films such as nylon and aromatic polyamide.

  Furthermore, the transparent substrate used in the conductive laminate of the present invention includes polyimide, polysulfone, polyethersulfone, polyetheretherketone, polyphenylene sulfide, polyvinyl alcohol, polyvinylidene chloride, polyvinyl butyral, polyarylate, polyoxymethylene. And a substrate made of a transparent polymer such as an epoxy resin and a blend of the above polymers. Among these transparent polymers, polycarbonate and polyethylene terephthalate are particularly preferable from the viewpoints of transparency, heat resistance, and versatility.

  In the use in the conductive laminate of the present invention, among these transparent substrates, those having a low optical birefringence, or a phase difference of 1/4 (λ / 4) of wavelength (for example, 550 nm) or 1 / of wavelength. Those controlled to 2 (λ / 2) and those not controlling birefringence at all can be appropriately selected according to the application. As mentioned here, when selecting appropriately according to the application, for example, by using polarized light such as linearly polarized light, elliptically polarized light, circularly polarized light, etc. A case where the conductive laminate of the present invention is used together with a display exhibiting a function can be given.

  The thickness of the transparent substrate can be appropriately determined, but is generally about 10 to 500 μm, particularly 20 to 300 μm, and more preferably 30 to 200 μm from the viewpoint of workability such as strength and handleability.

(Color difference adjustment layer)
In the conductive laminate of the present invention, a color difference adjusting layer is preferably present between the transparent substrate and the transparent conductive layer. This color difference adjusting layer may be a single layer or a layer composed of two layers or more. The color difference adjusting layer is a layer for improving adhesion between layers and optical properties (such as transmittance and color tone) of the conductive laminate.
The color difference adjusting layer is composed of a curable composition containing a cured resin component (i), metal oxide particles (ii), and an initiator (iii), and the cured resin component (i) has a urethane structure and has a molecular weight. Is a compound (B1) having a polymerizable functional group at a molecular weight of 1,000 to 300,000 and a compound (B2) having a structure expressing an intermolecular force and having a molecular weight of 200 to 50,000 and a polymerizable functional group Are preferably included. However, the compound (B1) and the compound (B2) are not the same compound.

(Curable composition)
(Curing resin component (i))
(Compound (B1))
The compound (B1) has a function of improving the bending resistance of the obtained color difference adjusting layer.

  The compound (B1) preferably has a polymerizable functional group. The polymerizable functional group is preferably a (meth) acryloyl group. Moreover, it is preferable to have 2 or more and 600 or less (meth) acryloyl groups.

  As said compound (B1), the urethane (meth) acrylate whose polystyrene conversion number average molecular weight is 1,000-300,000 in a gel permeation chromatography (GPC) is used suitably. The GPC pattern of the compound (B1) is measured using an HLC-8020 high performance liquid chromatograph (manufactured by Tosoh Corporation), using a styrene / divinylbenzene copolymer resin as a GPC column and tetrahydrofuran as an eluent. .

  The compound (B1) is not particularly limited as long as it is a compound having a (meth) acryloyl group and a urethane bond, and commercially available products thereof include, for example, Art Resin UN-333, KY-11, SK- 37, KY-111, UN-2600, UN-2700, H-34, H-17, UN-3320HA, UN-3320HS, UN-904M, UN-905, CDW-1, OF-048, LPVC-3 ( As mentioned above, manufactured by Negami Kogyo Co., Ltd.), EBECRYL230, EBECRYL270, EBECRYL4858, EBECRYL8807, EBECRYL9260, EBECRYL9270 (above, manufactured by Daicel-Cytec Co., Ltd.), U-6HA, U-6LPA, UA-1100H, UA-1100H , UA-4200, UA-12 P, UA-53H, UN-2600, UN-2700, GH-1203 (Shin-Nakamura Chemical Industry Co., Ltd.), and the like can be given.

  Content of the said compound (B1) is 1 mass% or more and 60 mass% or less normally in total solid, and 10 mass% or more and 50 mass% or less are preferable. By setting it as such a range, the bending resistance etc. of the color difference adjustment layer obtained can be improved effectively.

  Further, the content of the compound (B1) is preferably 5% by mass or more and 85% by mass or less, and preferably 5% by mass or more and 70% by mass or less in all (meth) acrylate components other than the component (ii) in the composition. Is more preferable. By setting it as such content, while a favorable softness | flexibility is effectively provided to a hard-coat layer, the higher balance with surface hardness can be aimed at. Here, all (meth) acrylate components other than (ii) component are (meth) acrylate components (having (meth) acryloyl groups) contained in all soluble components excluding (ii) component which is insoluble particles. Compound). Specifically, it means the total amount of the compound (B1), the compound (B2) and the compound (C) described in detail later.

(Compound (B2))
The compound (B2) having a structure that expresses the intermolecular force has a function of improving the scratch resistance and the like of the obtained color difference adjusting layer.

  Examples of the structure that expresses the intermolecular force of the compound (B2) include a urethane structure, a hydroxyl group, an amino group, and a carboxyl group. Among these, those having a urethane structure are preferable.

  The compound (B2) preferably has 2 or more (meth) acryloyl groups, more preferably 4 or more and 100 or less (meth) acryloyl groups.

  As the compound (B2), urethane (meth) acrylate having a polystyrene-equivalent number average molecular weight of 200 to 50,000 in gel permeation chromatography (GPC) is preferably used. The GPC pattern of the urethane (meth) acrylate compound (B2) uses an HLC-8020 high performance liquid chromatograph (manufactured by Tosoh Corporation), a styrene / divinylbenzene copolymer resin as a GPC column, and tetrahydrofuran as an eluent Use to measure.

  The (B2) is not particularly limited as long as it is a compound having a (meth) acryloyl group, and examples of commercially available products thereof include Art Resin UN-952, KY-11, SK-37, and KY-. 111, UN-2600, UN-2700, H-17, UN-3320HA, UN-3320HS, UN-904M, UN-905, OF-048, LPVC-3 (manufactured by Negami Industrial Co., Ltd.), EBECRYL230 , EBECRYL270, EBECRYL4858, EBECRYL8807, EBECRYL9260, EBECRYL9270 (manufactured by Daicel Cytec Co., Ltd.), U-4HA, U-6HA, U-6LPA, UA-1100H, UA-200PA, UA-4200 , UA-53H, UN-260 , UN-2700, GH-1203 (manufactured by Shin-Nakamura Kagaku Kogyo Co.), UA-306H, UA-306I (or more, Kyoeisha Co., Ltd.), and the like can be given. These can be used alone or in combination of two or more.

  Content of the said compound (B2) is 1 mass% or more and 60 mass% or less normally in a total solid, and 1 mass% or more and 40 mass% or less are preferable. By setting it as such a range, the bending resistance etc. of the color difference adjustment layer obtained can be improved effectively.

  In addition, the content of the compound (B2) is preferably 5% by mass or more and 85% by mass or less, and preferably 5% by mass or more and 50% by mass or less in all (meth) acrylate components other than the component (ii) in the composition. Is more preferable. By setting it as such content, while a favorable softness | flexibility is effectively provided to a color difference adjustment layer, the higher balance with surface hardness can be aimed at. Here, all (meth) acrylate components other than (ii) component are (meth) acrylate components (having (meth) acryloyl groups) contained in all soluble components excluding (ii) component which is insoluble particles. Compound). Specifically, it means the total amount of the component (B1), the component (B2) and the component (C) described in detail later.

(Compound (C))
The compound (C) is suitably used for increasing the adhesion between the color difference adjusting layer and the substrate 2 and adjusting the hardness. The (meth) acrylate compound (C) is a compound having one or more (meth) acryloyl groups in one molecule, and examples thereof include (meth) acrylic esters.

  The content of the compound (C) is preferably 1% by mass or more and 50% by mass or less, and more preferably 5% by mass or more and 40% by mass or less in the total solid sentence. When the amount is less than 1% by mass, the function of the compound (C) may not be sufficiently exhibited. When the amount exceeds 40% by mass, the bending resistance may be deteriorated.

(Metal oxide particles (ii))
The metal oxide particles (ii) are preferably oxide particles of at least one element selected from the group consisting of silicon, aluminum, zirconium, titanium, zinc, germanium, indium, tin, antimony and cerium. By using such oxide particles (ii), a highly transparent color difference adjusting layer can be obtained.

  Examples of the metal oxide particles (ii) include particles such as silica, alumina, zirconia, titanium oxide, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), antimony oxide, and cerium oxide. Can be mentioned. Among these, silica, alumina, zirconia, and antimony oxide particles are preferable from the viewpoint of high hardness. These can be used alone or in combination of two or more.

  The metal oxide particles (ii) are preferably used as a powder or dispersed sol. When used as a dispersion sol, the dispersion medium is preferably an organic dispersion medium from the viewpoint of dispersibility with other components. Examples of such an organic dispersion medium include alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ethyl acetate, butyl acetate, ethyl lactate, and γ- Esters such as butyrolactone, propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate; ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; aromatic hydrocarbons such as benzene, toluene and xylene; dimethylformamide and dimethylacetamide And amides such as N-methylpyrrolidone. Among these, methanol, isopropanol, butanol, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, toluene, and xylene are preferable.

  In order to improve the dispersibility of the particles, various surfactants and amines may be added.

  The shape of the metal oxide particles (ii) is not particularly limited, and can be spherical, hollow, porous, annular, rod-like, plate-like, fiber-like, chain-like, indeterminate, etc. Preferred are spherical and chain shapes.

  The average particle diameter of the metal oxide particles (ii) is preferably 0.001 μm to 2 μm, more preferably 0.003 μm to 1 μm, and particularly preferably 0.005 μm to 0.5 μm. When the average particle diameter exceeds 2 μm, the transparency after curing tends to decrease or the surface state tends to decrease. Conversely, when the average particle size is less than 0.001 μm, sufficient blocking resistance may not be exhibited.

  The average particle size is obtained by automatically calculating the particle size distribution according to the Mie theory from scattered light data measured by a batch measurement method using a laser diffraction / scattering particle size distribution measuring apparatus (for example, HORIBA LB-550). Mean median diameter. The median diameter is a particle diameter corresponding to a cumulative frequency distribution of 50%.

(Initiator (iii))
Examples of the initiator (iii) include a compound that generates active radical species (radiation (light) polymerization initiator) upon irradiation with radiation (light), a compound that thermally generates active radical species (thermal polymerization initiator), and the like. Can be mentioned. If necessary, a radiation (light) polymerization initiator and a thermal polymerization initiator can be used in combination.

  The radiation (photo) polymerization initiator is not particularly limited as long as it can be decomposed by light irradiation to generate radicals to initiate polymerization. For example, acetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2 , 2-dimethoxy-1,2-diphenylethane-1-one, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, benzoin propyl ether, benzoin ethyl ether, benzyl dimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy Roxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane -1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 2 , 4,6-trimethylbenzoyldiphenylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, oligo (2-hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl) propanone) and the like.

  As a commercial item of a radiation (photo) polymerization initiator, for example, Ciba Specialty Chemicals Co., Ltd. trade name: Irgacure 184, 369, 651, 500, 819, 907, 784, 2959, CGI 1700, CGI 1750, CGI 1850, CG24-61, Darocur 1116, 1173, manufactured by BASF, Inc. Product name: Lucilin TPO, manufactured by UCB, Inc. Product name: Ubekrill P36, manufactured by Fratteri Lamberti, Inc. Product names: Ezacure KIP150, KIP65LT, KIP100F, KT37, KT55, KTO46, KIP75 / B and the like.

  Examples of the thermal polymerization initiator include peroxides and azo compounds. Specific examples include benzoyl peroxide, t-butyl-peroxybenzoate, and azobisisobutyronitrile. .

  As content of the said initiator (iii), 0.01 to 10 mass% is preferable in a total solid, and 0.1 to 5 mass% is more preferable. If it is less than 0.01% by mass, the hardness may be insufficient, and if it exceeds 10% by mass, the interior of the color difference adjusting layer may not be sufficiently cured.

(Other polymerizable compounds)
The curable composition may contain other polymerizable compounds. Examples of the polymerizable compound include vinyl compounds.

  Examples of the vinyl compounds include divinylbenzene, ethylene glycol divinyl ether, diethylene glycol divinyl ether, and triethylene glycol divinyl ether.

(Other additives)
The curable composition may further contain other additives. Examples of the additive include a leveling agent, an ultraviolet absorber, an antioxidant, a light stabilizer, a pigment, a dye, a filling agent, a dispersant, a plasticizer, a surfactant, and a thixotropic agent.

  As the leveling agent, it is preferable to appropriately select and use a silicone-based or fluorine-based leveling agent. Examples of the silicone leveling agent include polydimethylsiloxane, polymethylalkylsiloxane, polyether-modified polydimethylsiloxane, polysiloxane having a (meth) acryl group, and the like.

  Examples of the ultraviolet absorber include benzotriazole-based, benzophenone-based, salicylic acid-based, and cyanoacrylate-based ultraviolet absorbers.

  Examples of the antioxidant include hindered phenol-based, sulfur-based, and phosphorus-based antioxidants.

  Examples of the light stabilizer include hindered amine light stabilizers.

  Each of these additives may be used alone or in combination of two or more. Moreover, as content of these other additives, 10 mass% or less is preferable in a total solid sentence, and 3 mass parts or less are preferable.

(solvent)
The curable composition is usually used after being diluted with a solvent in order to adjust the viscosity (coating property) and the thickness of the coating film. As a viscosity of the said curable composition, it is 0.1-50,000 mPa * second / 25 degreeC normally, Preferably it is 0.5-10,000 mPa * second / 25 degreeC.

  Examples of the solvent include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone cyclopentanone and cyclohexanone; esters such as ethyl acetate and butyl acetate; alcohols such as isopropyl alcohol and ethyl alcohol; benzene, toluene, xylene and methoxybenzene Aromatic hydrocarbons such as 1,2-dimethoxybenzene; phenols such as phenol and parachlorophenol; halogenated hydrocarbons such as chloroform, dichloromethane, dichloroethane, tetrachloroethane, trichloroethylene, tetrachloroethylene, and chlorobenzene It is done. These solvents can be used alone or in combination of two or more.

  The coating method of the curable composition is not particularly limited, and a known method can be used, and examples thereof include dipping coating, spray coating, flow coating, shower coating, roll coating, spin coating, brush coating, and the like. be able to.

  After the application of the curable composition, preferably after drying the solvent (volatile component) at 0 to 200 ° C., the color difference adjusting layer can be formed by performing a curing treatment with heat and / or radiation.

  When using heat, as the heat source, for example, an electric heater, an infrared lamp, hot air, or the like can be used. The preferable curing conditions in the case of heat are 20 to 150 ° C., and are performed within a range of 10 seconds to 24 hours.

In the case of radiation (light), the radiation source is not particularly limited as long as the composition can be cured in a short time after application. For example, as an infrared radiation source, a lamp, a resistance heating plate, Commercially available lasers, etc., as visible ray sources, sunlight, lamps, fluorescent lamps, lasers, etc., ultraviolet ray sources, mercury lamps, halide lamps, lasers, etc., and electron beam sources Using thermionic electrons generated from the tungsten filament, cold cathode method for generating metal through high voltage pulse, and secondary electron method using secondary electrons generated by collision between ionized gaseous molecules and metal electrode Can be mentioned. Moreover, as a source of alpha rays, beta rays, and gamma rays, for example, a fission material such as Co ₆₀ can be used. For the gamma rays, a vacuum tube that collides accelerated electrons with the anode can be used. These radiations can be irradiated alone or in combination of two or more at a certain time.

As the radiation, ultraviolet rays or electron beams are preferably used. In such a case, the preferable irradiation amount of ultraviolet rays is 0.01 to 10 J / cm ² , more preferably 0.1 to ² J / cm ² . Moreover, preferable irradiation conditions of the electron beam are an acceleration voltage of 10 to 300 kV, an electron density of 0.02 to 0.30 mA / cm ² , and an electron beam irradiation amount of 1 to 10 Mrad.

(Metal oxide layer)
In the transparent conductive laminate of the present invention, a metal oxide layer may be formed between the color difference adjusting layer and the transparent conductive layer as necessary. Examples of the component constituting the metal oxide layer include metal oxides such as silicon oxide, aluminum oxide, titanium oxide, magnesium oxide, zinc oxide, indium oxide, and tin oxide. Examples of the metal oxide layer include a layer having a thickness of 0.5 to 5.0 nm.

  By providing a metal oxide layer between the color difference adjusting layer and the transparent conductive layer, the adhesion between the layers can be improved. In addition, the presence of the metal oxide layer has an advantage that the performance such as durability of the laminate is improved.

  The metal oxide layer can be formed by a known method. As a method for forming a metal oxide layer, for example, a physical formation method such as a DC magnetron sputtering method, an RF magnetron sputtering method, an ion plating method, a vacuum deposition method, or a pulse laser deposition method (hereinafter referred to as “PVD method”). Can be used. Among these methods, the DC magnetron sputtering method, which can form a metal oxide layer with a uniform thickness and is excellent in industrial production, is particularly preferable. In addition to the above physical formation method (PVD method), chemical formation methods such as Chemical Vapor Deposition (hereinafter referred to as “CVD method”) and sol-gel method can also be used.

  The target used in the sputtering method is preferably a metal target. As the sputtering method, a reactive sputtering method is widely used. This is because it is difficult to use the DC magnetron sputtering method in the case of a metal oxide target because an oxide of an element used as a metal oxide layer is often an insulator. A pseudo RF magnetron sputtering method in which formation of an insulator on the target is suppressed by discharging the two cathodes simultaneously can also be used.

(Transparent conductive layer and conductive laminate)
In the conductive laminate of the present invention, a transparent conductive layer is formed on the color difference adjusting layer or the metal oxide layer. Although there is no restriction | limiting in particular as a constituent material of a transparent conductive layer, For example, a metal layer or a metal compound layer can be mentioned. Examples of the component constituting the transparent conductive layer include metal oxide layers such as silicon oxide, aluminum oxide, titanium oxide, magnesium oxide, zinc oxide, indium oxide, and tin oxide. Of these, a crystalline layer mainly composed of indium oxide is preferable, and a layer made of crystalline ITO (Indium Tin Oxide) is particularly preferably used.

  In the case where the transparent conductive layer is crystalline ITO, the crystal grain size need not be particularly limited, but is preferably 500 nm or less. If the crystal grain size exceeds 500 nm, the bending durability deteriorates, which is not preferable. Here, the crystal grain size is defined as the largest diagonal line or diameter in each polygonal or oval region observed under a transmission electron microscope (TEM). When the transparent conductive layer is amorphous ITO, environmental reliability may be lowered.

  The transparent conductive layer can be formed by a known method, for example, a physical forming method such as a DC magnetron sputtering method, an RF magnetron sputtering method, an ion plating method, a vacuum deposition method, a pulse laser deposition method, etc. Can be used. Focusing on industrial productivity of forming a metal compound layer having a uniform film thickness over a large area, the DC magnetron sputtering method is desirable. In addition to the physical formation method (PVD), a chemical formation method such as a chemical vapor deposition method or a sol-gel method can be used, but the sputtering method is desirable from the viewpoint of film thickness control.

  The film thickness of the transparent conductive layer is preferably 5 to 50 nm from the viewpoints of transparency and conductivity. More preferably, it is 5-30 nm. If the thickness of the transparent conductive layer is less than 5 nm, the resistance value tends to be inferior in stability with time. If the thickness exceeds 50 nm, the bending durability is lowered and coloring due to the transparent conductive layer becomes strong.

  When the conductive laminate of the present invention is used for a touch panel, the surface resistance value of the transparent conductive layer is more preferably 10 to 2000Ω / □ at a film thickness of 10 to 40 nm because of reduction in power consumption of the touch panel and circuit processing. Is preferably a transparent conductive layer showing a range of 30 to 1000Ω / □.

  As the transparent conductive layer, a wet dispersion method (for example, spin coating method, gravure, slot die, printing, etc.) on a polymer substrate with a dispersion liquid in which metal nanowires, carbon nanotubes, conductive oxide fine particles and the like are dispersed. A layer formed by the above can also be used.

  The transparent conductive layer thus formed is subjected to pattern formation by etching. This etching process is generally performed by covering the transparent conductive layer with a pattern formation mask and then etching the transparent conductive layer using an etching solution such as an acidic aqueous solution. Examples of the etchant include inorganic acids such as hydrogen chloride, hydrogen bromide, sulfuric acid, nitric acid, and phosphoric acid, organic acids such as acetic acid, and mixtures thereof, and aqueous solutions thereof. As a more specific etching solution, a strong acid aqueous solution obtained by mixing 12N hydrochloric acid, 16N nitric acid and water in a mass ratio of 12N hydrochloric acid: 16N nitric acid: water = 3.3: 1.0: 7.6 can be mentioned.

  In addition, before or after patterning a transparent conductive layer, you may heat-process as needed. In the case of ITO in which the transparent conductive layer is crystallized by heat treatment, there is an advantage that transparency and conductivity can be improved by performing the heat treatment. The heat treatment can be performed, for example, by heating at 100 to 150 ° C. for 15 to 180 minutes.

The conductive laminate of the present invention eliminates the reflection of the heat-treated conductive portion (X) on the side opposite to the surface having the conductive layer by, for example, applying a black tape, etc. To RX _λ when the light source in the wavelength range of 540 to 560 nm and 580 to 640 nm (λ) is irradiated, and there is a conductive layer with respect to the nonconductive portion (Y) excluding the transparent conductive layer by the etching solution The reflection on the side opposite to the surface is eliminated by applying a black tape, for example, and the reflectance when the light source in the wavelength λ range is irradiated from the surface with the conductive layer is RY _λ, and the reflection at the wavelength λ When the absolute value of the rate difference is ΔR _λ (= | RX _λ -RY _λ |), the total value Σ (ΔR _λ ) is 0.7 or less.

In FIG. 1, the reflectance RX _λ indicates the reflectance in the range of the wavelength λ in the conductive portion (X), and the reflectance RY _λ indicates the reflectance in the range of the wavelength λ in the conductive portion (Y).

  Measurement of the reflectance of the conductive laminate can be performed by measuring the absolute reflectance at an incident angle of 0 degree using a spectrophotometer such as Otsuka Electronics FE-3000.

  Note that the haze value of the conductive laminate is calculated in accordance with JIS K7361: 1997.

  The haze value can be measured using, for example, a haze meter (manufactured by Toyo Seiki Co., Ltd.).

(Anti-blocking layer)
In the conductive laminate of the present invention, an anti-blocking layer may be formed on the other surface of the transparent substrate as necessary. By forming the anti-blocking layer on the other surface, it is possible to suppress the occurrence of the blocking phenomenon in the production process of the conductive laminate, and there is an advantage that the storage stability during production is improved.

  The composition for forming the anti-blocking layer is the same as that described above as the material for forming the curable composition, and thus detailed description thereof is omitted.

(Hard coat layer)
In the conductive laminate of the present invention, a hard coat layer may be formed between the transparent substrate and the color difference adjusting layer as necessary.

  By forming the hard coat layer, it is possible to obtain a conductive laminate having both high bending resistance and blocking resistance. Since the composition for forming the hard coat layer is the same as that described above as the material for forming the curable composition, detailed description thereof is omitted.

(Touch panel)
The touch panel of this invention has the said conductive laminated body. Examples of the touch panel of the present invention include a capacitive touch panel. Further, the conductive laminate of the present invention may be used for a resistive film type touch panel.

  The following examples further illustrate the present invention, but the present invention is not limited thereto. In the examples, “parts” and “%” are based on mass unless otherwise specified.

[Example 1]
Preparation of Resin Composition 48.5 parts of polyurethane resin (compound (B1): Art Resin H-34 manufactured by Negami Kogyo Co., Ltd.) and 26.1 parts of polyurethane resin (compound (B2): UN-952 manufactured by Negami Kogyo Co., Ltd.) Then, 25.4 parts of polypropylene oxide-terminated acrylate (compound (C)) was mixed and stirred for 2 hours to obtain a uniform resin composition.

Adjustment of curable composition liquid 46.9 parts by dry weight of zirconia oxide dispersion liquid (A1) (Sakai Chemical Industry Co., Ltd .: SZR-K) having an average particle diameter of 40 nm as a dispersion liquid of metal oxide particles, The resin composition was mixed at a ratio of 52.7 parts and a polymerization initiator at a ratio of 1.4 parts (Irgacure 184 manufactured by BASF), and further diluted with methyl ethyl ketone (MEK), so that the solid content in the total weight of the curable composition liquid was 30. It adjusted so that it might become a part, and obtained the curable composition liquid.

Preparation of conductive laminate As a substrate, an anti-blocking coating solution (JSR: AB013) was applied to a 50 μm thick polyethylene terephthalate (PET) film (UH13 manufactured by Toray Industries, Inc.) so as to have a thickness of 1.5 μm. .
Further, the color difference adjusting layer was formed by coating and curing the curable composition liquid on the surface opposite to the surface having the anti-blocking layer of the substrate so that the dry thickness was 0.6 μm.
Subsequently, on the obtained color difference adjusting layer, the amorphous sputtering is performed by a reactive sputtering method using a silicon target and a reactive gas and a sputtering method using a target having a composition of indium oxide and tin oxide of 90:10 in mass ratio. A SiO ₂ layer (thickness 15 nm) and an ITO layer (thickness 22 nm) were formed. The obtained film was heat-treated at 150 ° C. for 1 hour to produce a conductive laminate in which ITO was crystallized. The surface resistance value of the obtained conductive laminate was 130Ω / □ (Mitsubishi Chemical Analytech: Loresta GP MCP-T610 type).

[Examples 2 to 4 and Comparative Examples 1 to 3]
Regarding the adjustment of the resin composition, it was adjusted in the same procedure as in Example 1 except that the composition ratio was changed to that described in Table 1. Thereafter, in the formation of the conductive laminate, the substrate thickness, the amount of metal oxide particles, the amount of resin, the cured thickness, and the thickness of the SiO ₂ layer were changed to those described in Table 1 as in Example 1. It was created according to the procedure.

Measurement of haze value The haze value of the conductive part (X) (manufactured by Toyo Seiki Co., Ltd .: Hazeguard II) was measured on the conductive laminate. This haze value is calculated according to JIS K7361: 1997.

Measurement of Σ (ΔR _λ ) After masking the conductive laminate with a 1 mm width tape at 1 mm intervals, a mass ratio of 12N hydrochloric acid: 16N nitric acid: water = 3.3: 1.0: 7.6 Etching was performed with a strong acid aqueous solution obtained by mixing in step 1 to form a pattern in which conductive portions (X) and nonconductive portions (Y) appear alternately. Reflection (RX _λ and RY _λ ) for each wavelength of 1 nm in a state where the reflection on the side opposite to the surface having the conductive layer of the obtained patterned conductive laminate is extinguished by applying a black tape and fixed to a flat plate Was measured (FIG. 1). Taking the absolute value △ R _lambda differences in the wavelength of 540~560nm and wavelength 580～640Nm, sum.

Preparation of Etching Mark Observation Sample After masking the obtained conductive laminate at 1 mm intervals using a 1 mm wide tape, the mass of 12N hydrochloric acid: 16N nitric acid: water = 3.3: 1.0: 7.6 Etching with a strong acid aqueous solution obtained by mixing at a ratio was performed to form a patterned conductive laminate in which conductive portions (X) and nonconductive portions (Y) appear alternately. A 50 μm thick touch panel OCA (LG: LG OC9052D) was attached to the surface of the patterned conductive laminate having the conductive layer, and the surface opposite to the surface laminated with the patterned conductive laminate. The surfaces without the conductive layer of the conductive laminate that was not patterned were pasted together. An OCA for 100 μm-thick touch panel (manufactured by LG: LG OC9102D) is attached to the other surface of the 100 μ-thick OCA on the other side of the 100 μm-thick OCA. Glass was pasted. The obtained glass bonded product was exposed at 50 ° C. and 85% for 30 minutes to obtain an etching mark observation sample.

Observation of etching mark The prepared observation sample was observed under a three-wavelength fluorescent lamp (SLH-399, manufactured by TWINBARD) in a dark room. Discriminated by the reflected light when the light of the three-wavelength fluorescent lamp is irradiated from the glass surface of the observation sample, and visually observed without any particular restrictions on the angle and distance between the observer, the fluorescent lamp, and the observation sample The determination was made based on the following evaluation criteria.
A: It is difficult or impossible to distinguish between the conductive part (X) and the non-conductive part (Y).
○: Slight discrimination between the conductive part (X) and the non-conductive part (Y) is possible.
X: The conductive part (X) and the non-conductive part (Y) can be easily distinguished.

From Table 1, the conductive laminates of Examples all have Σ (ΔR _λ ) of 0.7 or less and a haze value of 1.0% or less. Thereby, even after performing the etching process, it can be confirmed that extremely excellent visibility is secured. Furthermore, it is also an example in which the proportion of the compound (B1) and the compound (B2) in the total resin is 80 parts or less. Thereby, the haze value of an electroconductive laminated body becomes 1.0 or less, and it can confirm that visibility is ensured.
Comparisons 1 to 3 are examples in which ΣΔR is greater than 0.7. These were uniformly less visible and the etching marks were easy to observe. Furthermore, it is also an example in which the proportion of compound B1 and compound B2 in the total resin is greater than 80 parts. Thereby, the haze value of the electroconductive laminated body became larger than 1.0, and visibility fell.

Claims (8)

A conductive laminate having a part X having a transparent conductive layer and a part Y not having a transparent conductive layer on at least one surface A of the transparent substrate, and satisfying the following conditions (1) to (5).
(1) λ: integer.
(2) RX _λ : reflectivity (%) at the portion X measured from the surface A side when the wavelength is _λ nm.
(3) RY _λ : reflectivity (%) in the portion Y measured from the surface A side when the wavelength is _λ nm.
(4) ΔR _λ = | RX _λ -RY _λ | (%)
  2. The conductive laminate according to claim 1, wherein the haze is 1.0% or less.   The conductive laminate according to claim 1, further comprising a color difference adjusting layer between the surface A and the transparent conductive layer. The color difference adjusting layer comprises a curable composition containing a cured resin component (i), metal oxide particles (ii), and an initiator (iii).
The cured resin component (i) has a urethane structure, a molecular weight of 1,000 to 300,000, a compound (B1) having a polymerizable functional group, a structure that expresses intermolecular force, and a molecular weight. The conductive laminate according to claim 3, comprising a compound (B2) having a polymerizable functional group at 200 to 50,000. (However, the compound (B1) and the compound (B2) are not the same compound.)   The cured resin component (i) contains a total of less than 80 parts by weight of the compound (B1) and the compound (B2) with respect to 100 parts by weight of the dry weight of the component (i). Item 5. The conductive laminate according to Item 4.   The conductive laminate according to claim 1, wherein the transparent substrate has an anti-blocking layer on a surface B opposite to the surface A.   The conductive laminate according to claim 1, wherein the transparent conductive layer is a crystalline layer containing indium oxide, and the thickness of the transparent conductive layer is 5 to 50 nm. A touch panel comprising the conductive laminate according to claim 1.