JP2015035195A - Transparent conductive laminate, touch panel, and touch panel intermediate laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent conductive laminate which has superior transparency and is capable of sufficiently suppressing interference fringes.SOLUTION: A transparent conductive laminate comprises an undercoat layer and a conductive layer laminated on a light transmissive substrate in the described order, where the conductive layer has a concavo-convex pattern on a surface thereof. Defining θa as an average tilt angle of the concavo-convex portion, Rp as the maximum peak height of the concavo-convex pattern, and Rv as the maximum valley depth of the concavo-convex pattern, the concavo-convex pattern has a ratio of Rp to Rv of no more than 1.5 and θa that satisfies the following conditional expression: 0.01°≤θa≤0.10°.

Description

The present invention relates to a transparent conductive laminate, a touch panel, and an intermediate laminate for a touch panel.

Conventionally, a transparent conductive laminate in which a conductive film is formed on a light-transmitting substrate is a flat panel display such as a liquid crystal display device or an electroluminescence (EL) display, a transparent electrode of a touch panel, or the like. Widely used in field applications. In particular, in recent years, the demand for transparent conductive laminates has increased due to the spread of portable information terminals equipped with touch panels and notebook computers with touch panels.

As a transparent conductive laminate used for a touch panel, a structure in which a conductive film made of a conductive metal oxide such as ITO is formed on a light transmissive substrate made of a polymer material is known. From the viewpoint of preventing deterioration of transparency due to precipitation of low molecular weight components such as oligomers from the light transmissive substrate, curing is performed between the light transmissive substrate and the conductive layer for the purpose of preventing diffusion of low molecular weight components. It is known to form a resin layer (undercoat layer) (see, for example, Patent Document 1).

However, since the transparent conductive laminate mounted on such a touch panel has a multilayer structure in which an undercoat layer and a conductive layer are laminated on a light transmissive substrate, for example, a light transmissive substrate and The reflected light from the interface with the undercoat layer interferes with the reflected light from the surface of the undercoat layer, resulting in a problem that unevenness patterns called interference fringes appear due to unevenness in film thickness, and the appearance is impaired.

JP 2002-103504 A

In view of the above situation, the present invention is excellent in transparency and can sufficiently suppress the generation of interference fringes, a transparent conductive laminate, a touch panel using the transparent conductive laminate, and a touch panel The object is to provide an intermediate laminate.

The present invention is a transparent conductive laminate in which an undercoat layer and a conductive layer are laminated in this order on a light-transmitting substrate, and the conductive layer has a concavo-convex shape on the surface, When the average inclination angle of the concavo-convex part is θa, the maximum peak height of the concavo-convex is Rp, and the maximum valley depth of the concavo-convex is Rv, the ratio of Rp and Rv is 1.5 or less, and the θa is A transparent conductive laminate characterized by satisfying the formula.
0.01 ° ≦ θa ≦ 0.10 °

In the transparent conductive laminate of the present invention, the concavo-convex shape of the conductive layer preferably satisfies the following formula when the arithmetic average roughness of the concavo-convex is Ra.
0.02 μm ≦ Ra ≦ 0.10 μm
Moreover, as for the uneven | corrugated shape of the said conductive layer, it is preferable that the average wavelength (lambda) a represented by (lambda) = 2 (pi) * (Ra / tan ((theta) a)) satisfy | fills a following formula.
200 μm ≦ λa ≦ 800 μm
A high refractive index layer is preferably laminated between the undercoat layer and the conductive layer.
Moreover, it is preferable that a high refractive index layer and a low refractive index layer are laminated between the undercoat layer and the conductive layer.
The undercoat layer preferably contains inorganic oxide fine particles and a binder resin.
The inorganic oxide fine particles are preferably hydrophobized inorganic oxide fine particles.
The inorganic oxide fine particles form an aggregate and are contained in the undercoat layer, and the average particle diameter of the aggregate is preferably 100 nm to 2.0 μm.
Moreover, it is preferable that the transparent conductive laminated body of this invention has another undercoat layer on the side surface on the opposite side to the undercoat layer side of the said transparent base material.

The present invention is also a transparent conductive laminate in which an undercoat layer and a high refractive index layer are laminated in this order on a light transmissive substrate, and the high refractive index layer has an uneven shape on the surface. The uneven shape has a ratio of Rp to Rv of 1.5 or less when the average inclination angle of the uneven portion is θa, the maximum peak height of the unevenness is Rp, and the maximum valley depth of the unevenness is Rv. The transparent conductive laminate is characterized in that the θa satisfies the following formula.
0.01 ° ≦ θa ≦ 0.10 °
It is preferable to have a low refractive index layer on the side opposite to the undercoat layer side of the high refractive index layer.
The present invention is also a touch panel using the transparent conductive laminate of the present invention.
The present invention is also a touch panel intermediate laminate for supporting a patterned conductive layer in which an undercoat layer is laminated on a light-transmitting substrate, and the undercoat layer has an uneven shape on the surface. The concavo-convex shape has an average inclination angle of the concavo-convex portion of θa, the maximum peak height of the concavo-convex portion as Rp, and the maximum valley depth of the concavo-convex portion as Rv. There is also an intermediate laminate for a touch panel, wherein the θa satisfies the following formula.
0.01 ° ≦ θa ≦ 0.10 °
The present invention is described in detail below.

The inventors of the present invention have made extensive studies on a transparent conductive laminate used in a touch panel in which an undercoat layer and a conductive layer or a high refractive index layer are laminated in this order on one surface of a light-transmitting substrate. As a result, it has been found that by forming a predetermined uneven shape on the surface of the conductive layer or the high refractive index layer, a transparent conductive laminate having excellent interference fringe prevention performance can be obtained without impairing transparency. The present invention has been completed.

Here, conventionally, the transparent conductive laminate of the touch panel is taken up and rolled from the viewpoint of productivity improvement at the time of molding, but the conventional undercoat layer has a high surface smoothness. There was a problem that a phenomenon (so-called blocking) in which the overlapped films were adhered to each other occurred when the rolls were taken. When such blocking occurs, the film cannot be smoothly fed out from the roll, and in the next step, the film is wrinkled or the film meanders. Further, in the case of severe blocking, unevenness may occur at the blocked location, and the transparency and haze of the produced transparent conductive laminate, and further optical uniformity may be impaired.
In order to deal with such problems, for example, in Japanese Patent Application Laid-Open No. 10-323931 and Japanese Patent Application Laid-Open No. 2012-206502, fine particles are included in the undercoat layer to form irregularities on the surface, thereby blocking resistance and easy slipping. Conventionally, methods for improving the performance have been proposed.
However, in the conventional transparent conductive laminate, the uneven shape on the surface of the undercoat layer was formed only for the purpose of improving the blocking resistance and easy slipperiness, so that the occurrence of interference fringes is sufficiently suppressed. It was not something that could be done.
This is because the transparent conductive laminate in which fine particles are added to the conventional undercoat layer to improve the blocking resistance and the slipperiness is necessary to maintain the transparency and color tone of the undercoat layer. This is because the minimum uneven shape capable of exhibiting blocking resistance and easy slipping was formed on the surface of the undercoat layer by considerably reducing the amount of fine particles added. That is, the surface of the undercoat layer is in a substantially flat state in which the area of the planar portion is much larger than the area of the concavo-convex portion. As a result, the generation of interference fringes could not be sufficiently suppressed.
In other words, the surface irregularity shape of the undercoat layer formed for the purpose of improving the conventional blocking resistance and slipperiness, and the conductive layer or high refractive index that can sufficiently suppress the occurrence of interference fringes found by the present inventors. The shape of the irregularities on the surface of the layer is completely different.

In the transparent conductive laminate of the present invention, an undercoat layer and a conductive layer are laminated in this order on a light-transmitting substrate.
The light-transmitting substrate is not particularly limited, and examples thereof include polyester resins, acetate resins, polyethersulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, and (meth) acrylic resins. Examples include resins, polyvinyl chloride resins, polyvinylidene chloride resins, polystyrene resins, polyvinyl alcohol resins, polyarylate resins, polyphenylene sulfide resins, and the like. Of these, polyester resins, polycarbonate resins, and polyolefin resins are preferably used.

In addition, examples of the light transmissive substrate include an amorphous olefin polymer (Cyclo-Olefin-Polymer: COP) film having an alicyclic structure. This is a base material in which a norbornene polymer, a monocyclic olefin polymer, a cyclic conjugated diene polymer, a vinyl alicyclic hydrocarbon polymer, and the like are used. Zeonoa (norbornene resin), Sumitrite FS-1700 manufactured by Sumitomo Bakelite, Arton (modified norbornene resin) manufactured by JSR, Appel (cyclic olefin copolymer) manufactured by Mitsui Chemicals, Topas (cyclic) manufactured by Ticona Olefin copolymer), Optretz OZ-1000 series (alicyclic acrylic resin) manufactured by Hitachi Chemical Co., Ltd., and the like.
Further, the FV series (low birefringence, low photoelastic modulus film) manufactured by Asahi Kasei Chemicals is also preferable as an alternative base material for triacetylcellulose.

The thickness of the light transmissive substrate is preferably 2 to 200 μm. When the thickness is less than 2 μm, the mechanical strength of the light-transmitting substrate is insufficient, and when manufacturing the transparent conductive laminate of the present invention, the light-transmitting substrate is rolled to continuously form a conductive layer. Operation may be difficult. On the other hand, if it exceeds 200 μm, the scratch resistance of the conductive layer, which will be described later, and the dot characteristics for touch panels may not be improved. The thickness of the light transmissive substrate is more preferably 2 to 100 μm.

The light-transmitting substrate may be subjected to an etching treatment or undercoating treatment such as sputtering, corona discharge, ultraviolet irradiation, electron beam irradiation, chemical conversion, oxidation, etc. on the surface in advance. By performing these treatments in advance, the adhesion with the undercoat layer formed on the light-transmitting substrate can be improved. Moreover, before forming an undercoat layer or a conductive layer, the surface of the light-transmitting substrate may be dust-removed or cleaned by solvent cleaning, ultrasonic cleaning, or the like as necessary.

In the transparent conductive laminate of the present invention, the undercoat layer is formed on the light-transmitting substrate and has an uneven shape on the surface.
In the transparent conductive laminate of the present invention, a predetermined uneven shape is formed on the surface of the conductive layer laminated on the undercoat layer. The uneven shape on the surface of the conductive layer is the same as that of the undercoat layer. Preferably, the conductive layer is formed following the uneven shape formed on the surface, and the conductive layer substantially maintains the uneven shape on the surface of the undercoat layer. The above-mentioned “maintaining the uneven shape on the surface of the undercoat layer” means that the parameter indicating the uneven shape on the surface of the undercoat layer is substantially the same as the parameter indicating the uneven shape on the surface of the conductive layer. Means value. Therefore, the surface of the undercoat layer is formed with a concavo-convex shape that is equivalent to the concavo-convex shape of the surface of the conductive layer and optical performance such as transparency and interference fringe prevention.
Therefore, the uneven shape on the surface of the undercoat layer is appropriately adjusted so that the uneven shape on the surface of the conductive layer satisfies the predetermined parameter described above.
The concavo-convex shape formed on the surface of the conductive layer has a ratio of Rp and Rv where the average inclination angle of the concavo-convex part is θa, the maximum peak height of the concavo-convex part is Rp, and the maximum valley depth of the concavo-convex part is Rv. 1.5 or less, and the above θa satisfies the following formula.
0.01 ° ≦ θa ≦ 0.10 °

The reason why the interference fringes can be prevented by the uneven shape formed on the surface of the conductive layer is that the optical film thickness per minute area of the surface of the conductive layer is not detected although the diffusion of light reflected on the surface is not detected. This is because it is controlled to have an uneven shape that prevents light interference. As a result, the transparent conductive laminate of the present invention prevents the generation of interference fringes without causing the diffusion of reflected light on the surface of the conductive layer, and further has blocking resistance and slipperiness as described later. It is improving. The conductive layer needs to be inclined on the uneven surface, and the index is the average inclination angle θa of the uneven portion.
In the transparent conductive laminate of the present invention, the lower limit of the average inclination angle θa of the uneven portion is 0.01 °. If it is less than 0.01 °, the inclination is not sufficient and interference fringes cannot be prevented. Moreover, blocking resistance and slipperiness fall and blocking will generate | occur | produce when it rolls up at the time of manufacture of the transparent conductive laminated body of this invention, and is set as a roll. A preferable lower limit of the θa is 0.03 °, and a more preferable lower limit is 0.04 °. The upper limit of the average inclination angle θa of the uneven portion is 0.10 °. If it exceeds 0.10 °, the angle of inclination of the concavo-convex portion is excessively large, which causes a problem of cloudiness due to diffuse reflection of external light. A preferable upper limit is 0.09 °, and a more preferable upper limit is 0.08 °.

In the present invention, when the maximum peak height of the unevenness is Rp and the maximum valley depth of the unevenness is Rv, the ratio of Rp to Rv is 1.5 or less. The ratio of Rp and Rv is obtained as Rp / Rv when Rp> Rv, and as Rv / Rp when Rv> Rp.
The ratio of Rp and Rv indicates that the larger the value, the greater the difference between the peak height and the valley depth. At this time, there are a large and steep mountain portion and a small and gentle valley portion, and even if the average inclination angle θa satisfies the above range, the inclination angle distribution is biased. It shows that. That is, the mountain portion has a large inclination angle, and the valley portion has a small inclination angle. In such a case, in a portion where the inclination angle is large, light diffusion is excessively increased, and there is a possibility that a cloudiness problem may occur. On the other hand, in a portion where the inclination angle is small, interference fringes may not be suitably prevented. If the ratio of Rp and Rv is 1.5 or less, the difference in height between peaks and valleys is small, so that the bias in the inclination angle distribution can be moderately suppressed, and interference fringes can be suitably prevented. At the same time, the cloudiness can be suppressed. The ratio of Rp to Rv is preferably 1.3 or less, and more preferably 1.2 or less.

Moreover, in this invention, when the arithmetic mean roughness of the unevenness | corrugation of the said uneven | corrugated shape of the said conductive layer is set to Ra, it is preferable to satisfy | fill the following formula | equation.
0.02 μm ≦ Ra ≦ 0.10 μm
In the present invention, it is preferable to control the size (height) of each convex portion of the concavo-convex shape of the conductive layer, but the index is the arithmetic average roughness Ra.
The minimum with preferable arithmetic mean roughness Ra of the said unevenness | corrugation is 0.02 micrometer. When the Ra is less than 0.02 μm, the size (height) of each convex portion is too small with respect to the wavelength of light, and a diffusion effect may not be obtained, and interference fringes are sufficiently generated. It may not be possible to suppress. Moreover, blocking resistance and slipperiness may fall. A more preferable lower limit of Ra is 0.03 μm, and a more preferable lower limit is 0.04 μm. The preferable upper limit of Ra is 0.10 μm. When Ra is more than 0.10 μm, each convex portion becomes too large and the transmitted light is distorted, so that a clear image may not be obtained. A more preferred upper limit is 0.09 μm, and a still more preferred upper limit is 0.08 μm.

In the present invention, the average wavelength λa represented by λa = 2π × (Ra / tan (θa)) is preferably 200 μm or more and 800 μm or less.
The average wavelength λa is a parameter indicating an average interval of the unevenness on the surface of the conductive layer. When the average wavelength λa is less than 200 μm, the unevenness on the surface of the conductive layer is too small to prevent interference fringes, or the change in the inclination angle on the uneven surface is too large, resulting in white turbidity. There is a risk of being seen. If the average wavelength λa exceeds 800 μm, the change in the inclination angle on the uneven surface on the surface of the conductive layer is reduced, and there is a possibility that interference fringes cannot be prevented suitably. A more preferable lower limit of the average wavelength λa is 300 μm, and a more preferable upper limit is 600 μm.

Moreover, it is preferable that the ten-point average roughness (Rz) of the uneven | corrugated shape formed in the surface of the said conductive layer is less than 0.5 micrometer, and a more preferable upper limit is 0.3 micrometer. When the Rz is 0.5 μm or more, the unevenness formed on the surface of the conductive layer is too large, and a cloudiness may be observed. The lower limit of Rz is not particularly limited, and is appropriately adjusted within a range where a diffusion effect can be obtained.

In the present specification, the above θa, Rp, Rv, Ra, and Rz are values obtained for each reference length from a roughness curve obtained by a method according to JIS B 0601-1994. Ra and Rz are values defined in JIS B 0601-1994, and θa is described in a surface roughness measuring instrument: SE-3400 instruction manual (revised 1995.07.20) (Kosaka Laboratory Ltd.) As shown in FIG. 1, the arc tangent θa = tan ⁻¹ {(the sum (h ₁ + h ₂ + h ₃ +... + H _n ) of the heights of the convex portions existing in the reference length L. h ₁ + h ₂ + h ₃ +... + h _n ) / L}.
Rp is the maximum value of the peak height from the average line of the roughness curve at the reference length, and Rv is the maximum value of the valley depth from the average line of the roughness curve at the reference length. It is.
Such θa, Rp, Rv, Ra, and Rz are based on, for example, surface roughness measuring instrument: SE-3400 / manufactured by Kosaka Laboratory Ltd., in accordance with JIS B 0601-1994, and the following conditions: Can be obtained by measuring the roughness curve.
(1) The stylus of the surface roughness detector:
Model No./SE2555N (2μ stylus), manufactured by Kosaka Laboratory Ltd. (tip radius of curvature 2μm / vertical angle: 90 degrees / material: diamond)
(2) Measurement conditions of surface roughness measuring instrument:
Reference length (cutoff value λc of roughness curve): 2.5 mm
Evaluation length (reference length (cutoff value λc) × 5): 12.5 mm
Feeding speed of stylus: 0.5 mm / s
Preliminary length: (cutoff value λc) × 2
Vertical magnification: 2000 times Horizontal magnification: 10 times

The undercoat layer preferably contains inorganic oxide fine particles.
The inorganic oxide fine particle is a material that forms the uneven shape of the surface of the undercoat layer. In the transparent conductive laminate of the present invention, the inorganic oxide fine particle forms an aggregate to form the undercoat layer. It is preferable that the uneven shape of the surface of the said undercoat layer is formed by the aggregate of the inorganic oxide fine particles contained therein.
Examples of the inorganic oxide particles include silica fine particles, alumina fine particles, zirconia fine particles, titania fine particles, tin oxide fine particles, ATO particles, and zinc oxide fine particles.

The inorganic oxide fine particles are preferably surface-treated. Since the inorganic oxide fine particles are surface-treated, the distribution of the aggregates of the inorganic oxide fine particles in the undercoat layer can be suitably controlled, and the chemical resistance of the inorganic oxide fine particles themselves can be controlled. And improvement of saponification resistance.

The surface treatment is preferably a hydrophobizing treatment, and examples thereof include a method of treating the inorganic oxide fine particles with a silane compound having a methyl group or an octyl group.
Here, a hydroxyl group is usually present on the surface of the inorganic oxide fine particle, but the surface treatment reduces the hydroxyl group on the surface of the inorganic oxide fine particle, and the BET method of the inorganic oxide fine particle. The surface area of the undercoat layer can be reduced by reducing the specific surface area measured by the above, and preventing the inorganic oxide fine particles from agglomerating excessively. Can be formed.

The inorganic oxide fine particles are preferably amorphous. If the inorganic oxide fine particles are crystalline, the Lewis acidity of the inorganic oxide fine particles becomes strong due to lattice defects contained in the crystal structure, and excessive aggregation of the inorganic oxide fine particles cannot be controlled. is there.

As such inorganic oxide fine particles, for example, fumed silica is preferably used because it tends to aggregate itself and easily form an aggregate described later. Here, the fumed silica refers to amorphous silica having a particle size of 200 nm or less prepared by a dry method, and is obtained by reacting a volatile compound containing silicon in a gas phase. Specifically, for example, a silicon compound, for example, one produced by hydrolyzing SiCl ₄ in a flame of oxygen and hydrogen can be used. Specifically, AEROSIL R805 (made by Nippon Aerosil Co., Ltd.) etc. are mentioned, for example.

Although it does not specifically limit as content of the said inorganic oxide fine particle, It is preferable that it is 0.1-5.0 mass% in the said undercoat layer. When the amount is less than 0.1% by mass, the above-described specific uneven shape cannot be formed on the surface of the conductive layer, and interference fringes may not be prevented. When the amount exceeds 5.0% by mass, aggregates are excessively generated. In addition, since large surface irregularities are generated in the internal diffusion and / or undercoat layer, a problem of cloudiness may occur. A more preferable lower limit is 0.5% by mass, and a more preferable upper limit is 3.0% by mass.

The inorganic oxide fine particles preferably have an average primary particle diameter of 1 to 100 nm. When the thickness is less than 1 nm, the above-described specific uneven shape may not be formed on the surface of the conductive layer. When the thickness exceeds 100 nm, light is diffused by the inorganic oxide fine particles, and the transparent conductive laminate of the present invention is used. The dark room contrast of the touch panel may be inferior. A more preferred lower limit is 5 nm, and a more preferred upper limit is 50 nm.
In addition, the average primary particle diameter of the inorganic oxide fine particles is measured using an image processing software from an image of a cross-sectional electron microscope (a transmission type such as TEM or STEM and preferably a magnification of 50,000 times or more). Value.

The inorganic oxide fine particles preferably have a spherical shape in a single particle state. When the single particle of the inorganic oxide fine particles has such a spherical shape, a high-contrast display image can be obtained when the transparent conductive laminate of the present invention is applied to a touch panel.
In addition, the above “spherical” includes, for example, a true spherical shape, an elliptical spherical shape and the like, and has a meaning excluding so-called indefinite shape.

In the present invention, the aggregate of the inorganic oxide fine particles preferably has a structure in which the inorganic oxide fine particles described above are connected in a bead shape (pearl necklace shape) in the undercoat layer.
By forming the aggregate in which the inorganic oxide fine particles are arranged in a bead shape in the undercoat layer, the inorganic oxide fine particles are gathered gently, and the convex portion based on the aggregate has a small inclination. Since it becomes a gentle shape, it becomes easy to make the surface uneven | corrugated shape of the said conductive layer into the specific uneven | corrugated shape mentioned above.
The structure in which the inorganic oxide fine particles are connected in a bead shape is, for example, a structure in which the inorganic oxide fine particles are continuously connected in a straight line (linear structure), a structure in which a plurality of the linear structures are entangled, Any structure such as a branched structure having one or two or more side chains in which a plurality of inorganic oxide fine particles are continuously formed in the linear structure is mentioned.

In addition, the aggregate of the inorganic oxide fine particles preferably has an average particle diameter of 100 nm to 2.0 μm. When the thickness is less than 100 nm, the above-described specific uneven shape may not be formed on the surface of the conductive layer. When the thickness exceeds 2.0 μm, light is diffused by the aggregate of the inorganic oxide fine particles, and the transparent conductive material of the present invention. The dark room contrast of the touch panel using the conductive laminate may be inferior. The more preferable lower limit of the average particle diameter of the aggregate is 200 nm, and the more preferable upper limit is 1.5 μm.
The average particle diameter of the aggregates of the inorganic oxide fine particles is selected from a 5 μm square region containing a large amount of aggregates of inorganic oxide fine particles from observation with a cross-sectional electron microscope (about 10,000 to 20,000 times). The particle diameters of the aggregates of the inorganic oxide fine particles in the region are measured, and the particle diameters of the aggregates of the top 10 inorganic oxide fine particles are averaged. The “particle diameter of the aggregate of the inorganic oxide fine particles” is the maximum distance between the two straight lines when the cross section of the aggregate of the inorganic oxide fine particles is sandwiched between any two parallel straight lines. It is measured as the distance between straight lines in a combination of two straight lines. The particle diameter of the aggregate of the inorganic oxide fine particles may be calculated using image analysis software.

In the transparent conductive laminate of the present invention, for example, the undercoat layer preferably has a hardness of HB or more in a pencil hardness test (load 4.9 N) according to JIS K5600-5-4 (1999). More preferably, it is H or more.
The thickness of the undercoat layer is preferably 0.5 to 8.0 μm. If the thickness is less than 0.5 μm, precipitation of low molecular weight components such as oligomers from the light-transmitting substrate cannot be sufficiently prevented, and the surface of the undercoat layer may be easily damaged, and 8.0 μm If it exceeds, not only the undercoat layer cannot be made thin, but the undercoat layer may be easily broken. A more preferable range of the thickness of the undercoat layer is 1.0 to 5.0 μm. In addition, the thickness of the said undercoat layer can be measured by cross-sectional microscope observation.

In the undercoat layer, the inorganic oxide fine particles are preferably dispersed in a binder resin.
The binder resin preferably has a polarity adjusted according to the hydrophobicity of the hydrophobized inorganic oxide fine particles. Examples of the method for adjusting the polarity of the binder resin include adjusting the hydroxyl value of the binder resin. By optimizing the polarity of the binder resin, the aggregation / dispersibility of the inorganic oxide fine particles is suitably controlled, and the above-described specific uneven shape can be easily formed.

As said binder resin, a transparent thing is preferable, for example, it is preferable that the ionizing radiation hardening type resin which is resin hardened | cured by an ultraviolet-ray or an electron beam hardens | cures by irradiation of an ultraviolet-ray or an electron beam.
In the present specification, “resin” is a concept including monomers, oligomers, polymers and the like unless otherwise specified.

Examples of the ionizing radiation curable resin include compounds having one or more unsaturated bonds such as compounds having functional groups such as acrylates. Examples of the compound having one unsaturated bond include ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone and the like. Examples of the compound having two or more unsaturated bonds include trimethylolpropane tri (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, and pentaerythritol. Tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) ) Acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, tripentaerythritol octa (meth) acrylate Rate, tetrapentaerythritol deca (meth) acrylate, isocyanuric acid tri (meth) acrylate, isocyanuric acid di (meth) acrylate, polyester tri (meth) acrylate, polyester di (meth) acrylate, bisphenol di (meth) acrylate, diglycerin Polyfunctional compounds such as tetra (meth) acrylate, adamantyl di (meth) acrylate, isoboronyl di (meth) acrylate, dicyclopentane di (meth) acrylate, tricyclodecane di (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate Etc. Of these, pentaerythritol tetraacrylate (PETTA) is preferably used. In the present specification, “(meth) acrylate” refers to methacrylate and acrylate. In the present invention, as the ionizing radiation curable resin, a compound obtained by modifying the above-described compound with PO, EO or the like can also be used.

In addition to the above compounds, relatively low molecular weight polyester resins having unsaturated double bonds, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, etc. It can be used as an ionizing radiation curable resin.

The ionizing radiation curable resin is used in combination with a solvent-drying resin (a thermoplastic resin or the like, which is a resin that forms a film only by drying the solvent added to adjust the solid content during coating). You can also By using the solvent-drying resin in combination, film defects on the coated surface of the coating liquid can be effectively prevented when the undercoat layer is formed.
The solvent-drying resin that can be used in combination with the ionizing radiation curable resin is not particularly limited, and a thermoplastic resin can be generally used.
The thermoplastic resin is not particularly limited. For example, a styrene resin, a (meth) acrylic resin, a vinyl acetate resin, a vinyl ether resin, a halogen-containing resin, an alicyclic olefin resin, a polycarbonate resin, or a polyester resin. Examples thereof include resins, polyamide-based resins, cellulose derivatives, silicone-based resins, rubbers, and elastomers. The thermoplastic resin is preferably amorphous and soluble in an organic solvent (particularly a common solvent capable of dissolving a plurality of polymers and curable compounds). In particular, from the viewpoint of transparency and weather resistance, styrene resins, (meth) acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (cellulose esters, etc.) and the like are preferable.

The undercoat layer may contain a thermosetting resin.
The thermosetting resin is not particularly limited. For example, phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea cocondensation Examples thereof include resins, silicon resins, polysiloxane resins, and the like.

The undercoat layer containing the inorganic oxide fine particles and the binder resin is prepared by, for example, applying the composition for an undercoat layer containing the above-described inorganic oxide fine particles, a monomer component of the binder resin, and a solvent on a light-transmitting substrate. The coating film formed by applying and drying can be formed by curing by ionizing radiation irradiation or the like.

Examples of the solvent contained in the composition for the undercoat layer include alcohols (eg, methanol, ethanol, propanol, isopropanol, n-butanol, s-butanol, t-butanol, benzyl alcohol, PGME, ethylene glycol), ketones (Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic hydrocarbons (cyclohexane, etc.), aromatic hydrocarbons ( Toluene, xylene, etc.), halogenated carbons (dichloromethane, dichloroethane, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), cellosolve acetates, sulfur Kishido compound (dimethylsulfoxide), amides (dimethylformamide, dimethylacetamide, etc.) and the like can be exemplified, or a mixture thereof.

The undercoat layer composition preferably further contains a photopolymerization initiator.
The photopolymerization initiator is not particularly limited, and known ones can be used. Specific examples include, for example, acetophenones, benzophenones, Michler benzoylbenzoate, α-amyloxime ester, thioxanthones, propio Examples include phenones, benzyls, benzoins, and acylphosphine oxides. In addition, it is preferable to use a mixture of photosensitizers, and specific examples thereof include n-butylamine, triethylamine, poly-n-butylphosphine, and the like.

As the photopolymerization initiator, when the binder resin is a resin system having a radical polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, etc. may be used alone or in combination. preferable. When the binder resin is a resin system having a cationic polymerizable functional group, examples of the photopolymerization initiator include aromatic diazonium salts, aromatic sulfonium salts, aromatic iodonium salts, metallocene compounds, benzoin sulfonate esters, and the like. Are preferably used alone or as a mixture.

It is preferable that content of the said photoinitiator in the said composition for undercoat layers is 0.5-10.0 mass parts with respect to 100 mass parts of said binder resins. If it is less than 0.5 parts by mass, the hard coat performance of the undercoat layer to be formed may be insufficient, and if it exceeds 10.0 parts by mass, there is a possibility of inhibiting the curing. It is not preferable.

Although it does not specifically limit as a content rate (solid content) of the raw material in the said composition for undercoat layers, Usually, it is preferable to set it as 5-70 mass%, especially 25-60 mass%.

Depending on the purpose of increasing the hardness of the undercoat layer, suppressing curing shrinkage, controlling the refractive index, etc., the above-mentioned composition for undercoat layer may be a conventionally known dispersant, surfactant, antistatic agent, Silane coupling agent, thickener, anti-coloring agent, coloring agent (pigment, dye), antifoaming agent, leveling agent, flame retardant, UV absorber, adhesion-imparting agent, polymerization inhibitor, antioxidant, surface modification An agent, a lubricant, etc. may be added.
As the leveling agent, for example, silicone oil, fluorine-based surfactant, and the like are preferable because the undercoat layer is prevented from having a Benard cell structure. When a resin composition containing a solvent is applied and dried, a surface tension difference or the like is generated between the coating film surface and the inner surface in the coating film, thereby causing many convections in the coating film. The structure generated by this convection is called a Benard cell structure, and causes a problem such as the skin and coating defects in the formed undercoat layer.
Further, the Benard cell structure has a risk that the irregularity of the surface of the undercoat layer becomes too large and the appearance of the transparent conductive laminate is impaired. When the leveling agent as described above is used, this convection can be prevented, so that not only an undercoat layer free from defects and unevenness can be obtained, but also the uneven shape on the surface of the undercoat layer can be easily adjusted.

The method for preparing the composition for the undercoat layer is not particularly limited as long as each component can be uniformly mixed. For example, the composition can be performed using a known apparatus such as a paint shaker, a bead mill, a kneader, or a mixer.

The method for applying the undercoat layer composition onto the light-transmitting substrate is not particularly limited. For example, spin coating, dipping, spraying, die coating, bar coating, roll coater, meniscus coater And publicly known methods such as a method, a flexographic printing method, a screen printing method, and a pea coater method.
After applying the composition for an undercoat layer by any of the above methods, it is transported to a heated zone to dry the formed coating film, and the coating film is dried by various known methods to evaporate the solvent. By selecting the solvent relative evaporation rate, solid content concentration, coating solution temperature, drying temperature, drying air velocity, drying time, solvent atmosphere concentration in the drying zone, etc., the distribution state of the aggregates of inorganic oxide fine particles can be determined. Can be adjusted.
In particular, a method of adjusting the distribution state of the aggregates of inorganic oxide fine particles by selecting drying conditions is simple and preferable. The specific drying temperature is preferably 30 to 120 ° C., and the drying wind speed is preferably 0.2 to 50 m / s, and the inorganic oxidation is performed by performing the drying treatment appropriately adjusted within this range once or a plurality of times. It is possible to adjust the distribution state of the aggregates of the product fine particles to a desired state.

In addition, as a method of irradiating ionizing radiation when curing the coating film after drying, for example, a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, or a metal halide lamp is used. A method is mentioned.
Moreover, as a wavelength of an ultraviolet-ray, the wavelength range of 190-380 nm can be used. Specific examples of the electron beam source include various electron beam accelerators such as a cockcroft-wald type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type.

The transparent conductive laminate of the present invention preferably has another undercoat layer on the side surface opposite to the undercoat layer side of the light transmissive substrate. By having the other undercoat layer, the curling of the transparent conductive laminate of the present invention can be suppressed, and the generation of scratches in the production process can be reduced.
Moreover, it is also preferable that the functional layer mentioned later is laminated | stacked on the side opposite to the light transmissive base material side of said another undercoat layer.
Furthermore, it is preferable that the other undercoat layer has substantially the same surface asperity shape as the above-described undercoat layer.

The other undercoat layer can be formed using the same material as the above-described undercoat layer. By forming the other undercoat layer in this manner, the effects of blocking resistance and slipperiness of the transparent conductive laminate of the present invention can be enhanced.

In the transparent conductive laminate of the present invention, a high refractive index layer may be laminated between the undercoat layer and the conductive layer, and a high refractive index layer may be provided between the undercoat layer and the conductive layer. A refractive index layer and a low refractive index layer may be laminated.
The transparent conductive laminate of the present invention has a predetermined patterned conductive layer as will be described later. However, since it is a member used for a touch panel, the patterned conductive layer is made invisible. According to demand, the transparent conductive laminate of the present invention requires strict optical characteristics. For this reason, the high refractive index layer and the low refractive index layer are required to strictly control the thickness and refractive index. Specifically, the high refractive index layer preferably has a thickness of 10 to 100 nm and a refractive index of 1.60 to 1.70, and the low refractive index layer has a thickness of 10 to 100 nm and a refractive index of 1. It is preferable that it is 40-1.49. The thickness of the high refractive index layer and the low refractive index layer is more preferably 30 to 70 nm.
Note that a medium refractive index layer having a thickness of 200 nm or less and a refractive index of 1.50 to 1.70 may be provided between the high refractive index layer and the low refractive index layer. The middle refractive index layer has a thickness of 10 to 100 nm, preferably a refractive index of 1.55 to 1.65, and more preferably 30 to 70 nm.
In addition, the transparent conductive laminated body of this invention may have functional layers, such as an adhesion layer and a barrier layer, directly under a conductive layer.

Examples of the high refractive index layer and the medium refractive index layer include those containing a binder resin and refractive index adjusting particles.
As the refractive index adjusting particles, particles having a desired refractive index may be appropriately selected. Examples of particles having a relatively high refractive index include zinc oxide (1.90), titanium oxide (2.3 to 2.7), cerium oxide (1.95), and tin-doped indium oxide (1.95 to 2.95). 00), antimony-doped tin oxide (1.75 to 1.85), yttrium oxide (1.87), zirconium oxide (2.10), and the like. In addition, the inside of the said parenthesis shows the refractive index of the material of each particle. The average particle diameter of these particles is usually 100 nm or less.

The binder resin is not particularly limited. For example, a thermoplastic resin can be used, but from the viewpoint of increasing the surface hardness, a curable resin composition such as a thermosetting resin composition or an ionizing radiation curable resin composition. What is formed from the thing is preferable, and what is formed from the ionizing radiation curable resin composition is more preferable.
Examples of the thermosetting resin composition include curable resins such as acrylic resin, urethane resin, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin, and curing that is added as necessary. And the like, or those comprising a monomer constituting the curable resin and a curing agent.

Examples of the ionizing radiation curable resin of the ionizing radiation curable resin composition include compounds having one or more unsaturated bonds, such as a compound having an acrylate or methacrylate functional group. Examples of such a compound include the same compounds as the ionizing radiation curable resin described as the binder resin for the undercoat layer.

In addition, these compounds may have a refractive index adjusted to be high by introducing an aromatic ring, a halogen atom other than fluorine, sulfur, nitrogen, phosphorus atoms, or the like.
In addition to the above compounds, relatively low molecular weight polyester resins having unsaturated double bonds, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, etc. Can also be used as an ionizing radiation curable resin composition.

When the ionizing radiation curable resin composition is cured by ultraviolet irradiation, it is preferable that the composition contains an additive such as a photopolymerization initiator or a photopolymerization accelerator.
Examples of the photopolymerization initiator include acetophenone, benzophenone, Michler ketone, benzoin, benzyl methyl ketal, benzoyl benzoate, α-acyl oxime ester, α-hydroxy ketone, and thioxanthone. In the present invention, from the viewpoint of increasing the hardness of the high refractive index layer and the low refractive index layer, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methylpropionyl) benzyl] phenyl} -2- Methylpropan-1-one is preferred.
The photopolymerization accelerator is capable of reducing the polymerization obstacle due to air during curing and increasing the curing speed. For example, p-dimethylaminobenzoic acid isoamyl ester, p-dimethylaminobenzoic acid ethyl ester, etc. Is mentioned.

Examples of the low refractive index layer include those comprising a binder component and refractive index adjusting particles, and those comprising a single material having a low refractive index.
As the binder component, the binder resins exemplified in the high refractive index layer to the medium refractive index layer can be used. Further, a resin having a low refractive index such as a resin into which fluorine atoms are introduced or organopolysiloxane may be mixed as a binder component.
Examples of the refractive index adjusting particles used in the low refractive index layer include silica, magnesium fluoride, and hollow particles thereof. The average particle diameter of these particles is usually 100 nm or less.
When the low refractive index layer is formed from a single material having a low refractive index, for example, a material having a low refractive index such as a resin into which fluorine atoms are introduced or organopolysiloxane can be used.

In the transparent conductive laminate of the present invention, the material constituting the conductive layer is not particularly limited. For example, indium, tin, zinc, gallium, antimony, titanium, silicon, zirconium, magnesium, aluminum, gold, silver, A metal or metal oxide containing at least one metal element selected from the group consisting of copper, palladium, and tungsten is preferably used. The metal oxide may further contain a metal atom shown in the above group, if necessary. For example, indium oxide (ITO) containing tin oxide and tin oxide (ATO) containing antimony are preferably used.

The thickness of the conductive layer is not particularly limited, but is preferably 10 nm or more, more preferably 15 nm or more, and even more preferably 20 nm or more from the viewpoint of ensuring good conductivity with a surface resistance of 1 × 10 ³ Ω / □ or less. preferable. On the other hand, if the thickness of the conductive layer becomes too large, the above-described effect of invisibility by the high refractive index layer and the low refractive index layer may be reduced, and inconvenience that transparency may be reduced may occur. The thickness of the layer is preferably 60 nm or less, more preferably 50 nm or less, and still more preferably 40 nm or less.

When the material constituting the conductive layer is the metal material, the conductive layer made of the metal material usually has a light shielding property, so that a solid wiring causes deterioration in visibility. For this reason, it is preferable that the conductive layer made of the metal material is configured with a detection pattern using a conductive wire having a width of about several μm to 20 μm, for example.
In addition, when the detection pattern by such a conductive wire is arranged in a mesh shape, the light transmittance is different between the region occupied by the conductive wire and the other region. When a touch panel is used, the display quality is degraded. For this reason, when it has a conductive layer made of the metal material, it is preferable to improve visibility by appropriately providing a dummy pattern on the same plane as the detection pattern using the conductive wire, for example. In addition, as a detection pattern by the conducting wire which improved this visibility, the method of Unexamined-Japanese-Patent No. 2013-143045 etc. are mentioned, for example, In this case, the thickness of a conductive layer is not in the said range. Also good.

In the transparent conductive laminate of the present invention, when the conductive layer is made of the metal oxide described above, the refractive index of the conductive layer is preferably 1.81 or higher, more preferably 1.85 or higher. More preferably, 90 or more. The upper limit of the refractive index of the conductive film is preferably 2.20 or less, and more preferably 2.10 or less.

It does not specifically limit as a formation method of the said conductive layer, A conventionally well-known method can be used. Specifically, for example, a dry process such as a vacuum deposition method, a sputtering method, or an ion plating method can be used. In addition, an appropriate method can be adopted depending on the required film thickness.
In the transparent conductive laminate of the present invention, the conductive layer is laminated on the undercoat layer. The uneven shape formed on the surface of the undercoat layer is the surface of the conductive layer as described above. Is also maintained. For example, when the conductive layer is formed on the undercoat layer by a dry process such as a sputtering method, the surface of the formed conductive layer maintains the uneven shape of the surface of the undercoat layer in the same range. Therefore, blocking resistance and slipperiness can be imparted to the surface of the conductive layer formed on the undercoat layer.
In the case where a high refractive index layer and a low refractive index layer are laminated between the undercoat layer and the conductive layer, the high refractive index layer and the low refractive index layer are formed in an uneven shape on the surface of the undercoat layer. In this case, if the conductive layer is formed on the low refractive index layer by a dry process such as a sputtering method, the undercoat is also applied to the surface of the conductive layer as described above. An uneven shape in which the uneven shape on the surface of the layer is maintained in the same range is formed, and blocking resistance and easy slipperiness can be imparted to the surface of the conductive layer.

Since the transparent conductive laminate of the present invention is suitably used for a capacitive touch panel, the conductive layer is preferably patterned. Such a patterned conductive layer can be obtained, for example, by patterning the conductive layer formed by the above-described method.
Note that pattern portions and non-pattern portions are formed by patterning the conductive layer. Examples of the shape of the pattern portion include a stripe shape and a lattice shape.

The patterning of the conductive layer is generally performed by etching. For example, the conductive layer is patterned by forming a patterned etching resist film on the conductive layer by a photolithography method, a laser exposure method, or a printing method and then performing an etching process.

A conventionally well-known thing is used as said etching liquid. For example, an inorganic acid such as hydrogen chloride, hydrogen bromide, sulfuric acid, nitric acid or phosphoric acid, an organic acid such as acetic acid, a mixture thereof, an aqueous solution thereof, or the like is used.

The conductive layer can be crystallized by performing a heat annealing treatment as necessary.
By crystallizing the conductive layer, the resistance of the conductive layer is reduced, and transparency and durability are improved.
Note that when the conductive layer is patterned by the above-described etching, if the conductive layer is crystallized first, patterning by etching may be difficult. For this reason, the heat annealing treatment of the conductive layer is preferably performed after patterning the conductive layer.

Here, in the transparent conductive laminate of the present invention, the unevenness formed on the surface of the conductive layer satisfies the above-mentioned predetermined parameters, but the uneven shape satisfying such parameters is conventionally known. Compared with the concave and convex shape such as an undercoat layer formed for the purpose of improving the blocking resistance and the slipperiness, the convex portion has a small slope and a very gentle shape. That is, the uneven shape on the surface of the undercoat layer also has a very gentle shape with a small inclination of the convex portion.
Since the conductive layer is formed on such a concavo-convex gently uneven undercoat, unevenness during film formation of the conductive layer hardly occurs, and as a result, the in-plane distribution of the resistance value of the conductive layer is reduced. It becomes good.
Heretofore, for the purpose of imparting antiglare properties, an optical laminate (antiglare film) having a concavo-convex shape on the surface of the optical functional layer is known, but the transparent conductive laminate of the present invention is as described above. It is different from an antiglare film. That is, the uneven shape formed on the surface of the conductive layer of the transparent conductive laminate of the present invention has a lower uneven height than the uneven shape formed on the surface of the conventional antiglare film, The inclination angle of the concavo-convex part is gentler. Therefore, in the transparent conductive laminate of the present invention in which such a concavo-convex shape is formed in the conductive layer, the antiglare property as in the conventional antiglare film cannot be obtained. On the other hand, according to the present invention, it is possible to obtain a transparent conductive laminate that provides an image with excellent contrast without causing the occurrence of white turbidity due to external light, which is a problem with antiglare films.

Further, for example, as described in JP 2007-90656 A, one or more adjacent two layers having different refractive indexes are included, and predetermined fine irregularities are provided on an interface of at least one of the adjacent two layers, Also known are translucent articles that prevent the occurrence of interference fringes. However, the fine irregularities provided in this translucent article have a so-called moth-eye structure, and the fine irregularities of such a moth-eye structure are compared with the surface irregularities of the conductive layer in the transparent conductive laminate of the present invention. Thus, the slope of the convex portion is steeper and the value of θa is larger.
Therefore, the shape of the conventional uneven shape of the moth-eye structure and the uneven shape of the surface of the conductive layer that can sufficiently suppress the occurrence of interference fringes found by the present inventors are completely different.

In the transparent conductive laminate of the present invention, the conductive layer may be provided on both sides of the light transmissive substrate. In this case, one conductive layer is provided on the light-transmitting substrate via an undercoat layer having a predetermined uneven shape on the surface described above, while the other conductive layer is formed on the light-transmitting substrate. It may be directly provided on the light-transmitting base material via the other undercoat layer. That is, the other conductive layer may be provided directly on the side opposite to the side of the undercoat layer having a predetermined concavo-convex shape on the above-described surface of the light-transmitting substrate. It may be provided on the side of the layer opposite to the light transmissive substrate.
Here, when the transparent conductive laminate of the present invention is a wound body in which a long sheet as described later is wound in a roll shape, the one conductive layer and the other conductive layer are in direct contact with each other. It will be in the state. Thus, when the conductive layers are in direct contact with each other, in the transparent conductive laminate in which fine particles are added to the conventional undercoat layer to improve the blocking resistance and the slipperiness, as described above, Since the surface was in a substantially flat state, adhesion between the conductive layers (blocking property and slipperiness), and when the conductive layer is made of a metal material, the conductive layer is damaged. On the other hand, in the transparent conductive laminate of the present invention, a predetermined uneven shape is formed on the surface of the conductive layer on the undercoat layer, and excellent blocking resistance and slipperiness are imparted. Even when it is a wound body, the adhesion (blocking property and easy slipperiness) between the conductive layers provided on both sides of the light-transmitting substrate does not become a problem, and the conductive layer is damaged. Can also be effectively prevented.

The transparent conductive laminate of the present invention can be a wound body in which a long sheet is wound in a roll shape. The wound body of the long sheet of the transparent conductive laminate of the present invention uses a roll-shaped wound body of a long sheet as a light-transmitting substrate, and the undercoat layer, the high refractive index layer, and the low refractive index layer. The conductive layer can be formed by a roll-to-roll method. In forming such a wound body, a protective film provided with a weak adhesive layer may be bonded to the surface of the transparent conductive laminate as a separator and then wound in a roll shape. Since the transparent conductive laminate has improved blocking resistance and easy slipperiness, it is possible to form a roll of a long sheet of the transparent conductive laminate without using the protective film.

It does not specifically limit as a structure of the transparent conductive laminated body of this invention, For example, the following structures are mentioned.
A configuration (1) in which an undercoat layer and a conductive layer are laminated in this order on the light transmissive substrate.
A configuration (2) in which a high refractive index layer is provided between the undercoat layer and the conductive layer of the configuration (1).
A configuration (3) in which a high refractive index layer and a low refractive index layer are provided in this order between the undercoat layer and the conductive layer of the configuration (1).
Configuration (4) in which another undercoat layer is provided on the side opposite to the side on which the undercoat layer is provided of the light-transmitting substrate of any one of the above configurations (1) to (3).
Another undercoat layer is provided on the side opposite to the side on which the undercoat layer is provided of the light transmissive substrate of any one of the above configurations (1) to (3), and the light transmission of the other undercoat layer is achieved. The structure (5) by which the high refractive index layer was provided in the opposite side to the conductive base material side.
Another undercoat layer is provided on the side opposite to the side on which the undercoat layer is provided of the light transmissive substrate of any one of the above configurations (1) to (3), and the light transmission of the other undercoat layer is achieved. The high refractive index layer and the low refractive index layer are provided in this order on the side opposite to the conductive substrate side (6).

Furthermore, the present invention according to another aspect is a transparent conductive laminate in which an undercoat layer and a high refractive index layer are laminated in this order on a light-transmitting substrate, and the high refractive index layer includes: The surface has a concavo-convex shape, and the concavo-convex shape has a ratio of Rp to Rv where θa is the average inclination angle of the concavo-convex portion, Rp is the maximum peak height of the concavo-convex portion, and Rv is the maximum valley depth of the concavo-convex portion The transparent conductive laminate is characterized in that it is 1.5 or less and the θa satisfies the following formula.
0.01 ° ≦ θa ≦ 0.10 °

As the light-transmitting substrate, the undercoat layer, and the high refractive index layer constituting the transparent conductive laminate of the present invention according to another aspect, the light transmittance described in the above-described transparent conductive laminate of the present invention. The thing similar to a base material, an undercoat layer, and a high refractive index layer is mentioned.
The transparent conductive laminate of the present invention according to another aspect preferably has a low refractive index layer on the side opposite to the undercoat layer side of the high refractive index layer, and the low refractive index layer The same as the low refractive index layer described in the above-described transparent conductive laminate of the present invention. In this case, it is preferable that an uneven shape maintaining the surface uneven shape of the high refractive index layer is formed on the surface of the low refractive index layer. That is, it is preferable that an uneven shape satisfying the ratio of θa and Rp and Rv is formed on the surface of the low refractive index layer.

Here, the “conductive” of the transparent conductive laminate according to another aspect is suitably used as a member constituting the touch panel as described later, and therefore any conductivity for maintaining conductivity. It means that the member is provided with a configuration.
In the following description, the above-described transparent conductive laminate of the present invention and the transparent conductive laminate of the present invention according to another aspect are collectively referred to as the transparent conductive laminate of the present invention.

The transparent conductive laminate of the present invention can be applied to, for example, an optical system, an ultrasonic system, a capacitive system, a resistive film type touch panel, etc., among which it can be suitably applied to a capacitive system touch panel.
Such a touch panel using the transparent conductive laminate of the present invention is also one aspect of the present invention.

In forming the touch panel of the present invention, another transparent substrate such as glass or a polymer film can be bonded to one or both main surfaces of the transparent conductive laminate of the present invention via an adhesive layer. For example, you may form the laminated body by which the transparent base | substrate was bonded together through the transparent adhesion layer on the surface by which the conductive layer of the transparent conductive laminated body is not formed. The transparent substrate may be composed of a single substrate film, or may be a laminate of two or more substrate films (for example, laminated via a transparent adhesive layer). In addition, a hard coat layer can be provided on the outer surface of the transparent substrate to be bonded to the transparent conductive laminate.

The adhesive layer used for bonding the transparent conductive laminate and the transparent substrate is not particularly limited as long as it has transparency. Specifically, for example, acrylic polymers, silicone polymers, polyesters, polyurethanes, polyamides, polyvinyl ethers, vinyl acetate / vinyl chloride copolymers, modified polyolefins, epoxy systems, fluorine systems, natural rubbers, rubbers such as synthetic rubbers, etc. Those having the above polymer as a base polymer can be appropriately selected and used. In particular, an acrylic pressure-sensitive adhesive is preferably used from the viewpoint that it is excellent in optical transparency, exhibits adhesive properties such as appropriate wettability, cohesiveness and adhesiveness, and is excellent in weather resistance and heat resistance.

In the touch panel using the transparent conductive laminate of the present invention, generation of interference fringes is sufficiently suppressed, and the touch panel is excellent in transparency and visibility. Moreover, since the transparent conductive laminate of the present invention is excellent in blocking resistance and slipperiness as described above, it can be efficiently produced by a roll-to-roll method. Furthermore, since the undercoat layer in the transparent conductive laminate of the present invention has a very smooth surface irregularity, the conductive layer laminated thereon is less likely to cause unevenness during film formation. The in-plane distribution of the resistance value of the layer is good.

Since the transparent conductive laminate of the present invention has the above-described configuration, it is excellent in transparency and can sufficiently suppress the generation of interference fringes.
For this reason, the transparent conductive laminated body of this invention can be applied suitably for a touch panel, especially a capacitive touch panel.

It is explanatory drawing of the measuring method of (theta) a.

The contents of the present invention will be described with reference to the following examples, but the contents of the present invention should not be construed as being limited to these embodiments.

Example 1
A light-transmitting substrate composed of a biaxially stretched polyethylene terephthalate film (PET film) having a thickness of 100 μm was prepared, and an undercoat layer composition having the composition shown below was applied to one side of the light-transmitting substrate, A coating film was formed. Next, 70 ° C. dry air was passed through the formed coating film at a flow rate of 0.2 m / s for 15 seconds, and then 70 ° C. dry air was passed through for 30 seconds at a flow rate of 10 m / s. By evaporating the solvent in the coating film, the integrated light quantity is 100 mJ / cm in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) using an ultraviolet irradiation device (light source H bulb manufactured by Fusion UV System Japan Co., Ltd.). An undercoat layer having a thickness of 4 μm (at the time of curing) was formed by irradiating to ² to cure the coating film.
(Composition for undercoat layer)
Fumed silica (octylsilane treatment; average particle size 12 nm, manufactured by Nippon Aerosil Co., Ltd.)
1 part by mass pentaerythritol tetraacrylate (PETTA) (product name: PETA, manufactured by Daicel Cytec) 60 parts by mass urethane acrylate (product name: UV1700B, manufactured by Nippon Synthetic Chemical Co., Ltd.) 40 parts by mass Irgacure 184 (manufactured by BASF Japan) 5 parts by mass polyether-modified silicone (TSF4460, manufactured by Momentive Performance Materials) 0.025 parts by mass Toluene 105 parts by mass Isopropyl alcohol 30 parts by mass Cyclohexanone 15 parts by mass Fumed silica is a silane compound having an octyl group (For example, octylsilane) is used to hydrophobize a silanol group with an octylsilyl group.

Next, a composition for a high refractive index layer and a composition for a low refractive index layer having the following composition were prepared, and after the formation of the undercoat layer, the composition for a high refractive index layer was applied and dried continuously without winding. Then, a high refractive index layer having a thickness of 50 nm was formed by irradiating with ultraviolet rays, and a low refractive index layer having a thickness of 40 nm was formed by continuously applying the composition for low refractive index layer, drying and irradiating with ultraviolet rays.

(Composition for high refractive index layer)
Pentaerythritol triacrylate (PETA) (Product name: PETIA, manufactured by Daicel Cytec) 0.8 parts by mass High refractive index zirconia particles (Product name: MZ-230X, manufactured by Sumitomo Osaka Cement) 4 parts by mass polymerization initiator ( Irgacure 127, manufactured by BASF Japan Ltd.) 0.05 parts by mass leveling agent (manufactured by Dainichi Seika Kogyo Co., Ltd., Seika Beam 10-28 (MB)) 0.02 parts by mass methyl ethyl ketone (MEK) 38 parts by mass methyl isobutyl ketone (MIBK) 38 20 parts by mass of cyclohexanone by mass

(Composition for low refractive index layer)
Pentaerythritol triacrylate (PETA) (Product name: PETIA, manufactured by Daicel-Cytec) 0.6 parts by mass Low refractive index silica particles (Nissan Chemical Co., Ltd., MIBK-ST, solid content 30%) 2.0 parts by mass polymerization Initiator (Irgacure 127, manufactured by BASF Japan) 0.08 mass part leveling agent (manufactured by Dainichi Seika Kogyo Co., Ltd., Seika Beam 10-28 (MB)) 0.02 mass parts methyl isobutyl ketone (MIBK) 76 mass parts cyclohexanone 20 Parts by mass

Then, on the formed low refractive index layer, a sintered body composed of 90% by weight of indium oxide and 10% by weight of tin oxide was used in an atmosphere of 0.53 Pa composed of 80% argon gas and 20% oxygen gas. A conductive layer (ITO film) having a thickness of 25 nm was formed by sputtering, and a transparent conductive laminate according to Example 1 was manufactured.

(Example 2)
An undercoat layer composition was prepared in the same manner as in Example 1 except that the blended amount of fumed silica was 1.5 parts by mass. Except that the undercoat layer composition was used, Example 1 and Similarly, a transparent conductive laminate according to Example 2 was produced.

Example 3
An undercoat layer composition was prepared in the same manner as in Example 1 except that the amount of fumed silica was changed to 0.5 parts by mass. Except that the undercoat layer composition was used, Example 1 and Similarly, a transparent conductive laminate according to Example 3 was produced.

Example 4
An undercoat layer composition was prepared in the same manner as in Example 1 except that the amount of fumed silica was 2.5 parts by mass. Except that the undercoat layer composition was used, Example 1 and Similarly, a transparent conductive laminate according to Example 4 was produced.

(Example 5)
A transparent conductive laminate according to Example 5 was produced in the same manner as in Example 1 except that the conductive layer was not formed on the low refractive index layer.

(Example 6)
A transparent conductive laminate according to Example 6 was produced in the same manner as in Example 2 except that the conductive layer was not formed on the low refractive index layer.

(Example 7)
A transparent conductive laminate according to Example 7 was produced in the same manner as in Example 3 except that the conductive layer was not formed on the low refractive index layer.

(Example 8)
A transparent conductive laminate according to Example 8 was produced in the same manner as in Example 4 except that the conductive layer was not formed on the low refractive index layer.

(Comparative Example 1)
A composition for an undercoat layer was prepared in the same manner as in Example 1 except that no fumed silica was added, and Comparative Example 1 was made in the same manner as in Example 1 except that the composition for undercoat layer was used. A transparent conductive laminate was prepared.

(Comparative Example 2)
Except that 3 parts by mass of organic fine particles (hydrophilic treatment acrylic-styrene copolymer particles, average particle size 2.0 μm, refractive index 1.55, manufactured by Sekisui Plastics Co., Ltd.) was added, the same procedure as in Example 1 was performed. A transparent conductive laminate according to Comparative Example 2 was produced in the same manner as in Example 1 except that an undercoat layer composition was prepared and the undercoat layer composition was used.

(Comparative Example 3)
The same as in Example 1 except that 1.5 parts by mass of organic fine particles (hydrophilic treatment acrylic-styrene copolymer particles, average particle size 2.0 μm, refractive index 1.515, manufactured by Sekisui Plastics Co., Ltd.) was added. A transparent conductive laminate according to Comparative Example 3 was produced in the same manner as in Example 1 except that an undercoat layer composition was prepared and the undercoat layer composition was used.

(Comparative Example 4)
An undercoat layer composition was prepared in the same manner as in Example 1 except that the amount of fumed silica was changed to 4 parts by mass, and the same procedure as in Example 1 was performed except that the undercoat layer composition was used. Thus, a transparent conductive laminate according to Comparative Example 4 was produced.

(Comparative Example 5)
A transparent conductive laminate according to Comparative Example 5 was produced in the same manner as Comparative Example 1 except that no conductive layer was formed on the low refractive index layer.

(Comparative Example 6)
A transparent conductive laminate according to Comparative Example 6 was produced in the same manner as Comparative Example 2 except that no conductive layer was formed on the low refractive index layer.

(Comparative Example 7)
A transparent conductive laminate according to Comparative Example 7 was produced in the same manner as Comparative Example 3 except that no conductive layer was formed on the low refractive index layer.

(Comparative Example 8)
A transparent conductive laminate according to Comparative Example 8 was produced in the same manner as Comparative Example 4 except that no conductive layer was formed on the low refractive index layer.

The transparent conductive laminates according to the obtained Examples and Comparative Examples were evaluated for the following items.
All the results are shown in Table 1.

(Average inclination angle (θa) of uneven portion, maximum peak height (Rp) of uneven portion, maximum valley depth (Rv) of uneven portion, and arithmetic average roughness (Ra) of uneven portion)
Surface roughness measuring device: SE-3400 / manufactured by Kosaka Laboratory Co., Ltd. is used to measure the roughness curve in accordance with JIS B 0601-1994 and under the following conditions, and θa, Rp, Rv and Ra was measured. In addition, Rp and Rv are calculated | required from the roughness curve instead of a cross section curve.
(1) The stylus of the surface roughness detector:
Model No./SE2555N (2μ stylus), manufactured by Kosaka Laboratory Ltd. (tip radius of curvature 2μm / vertical angle: 90 degrees / material: diamond)
(2) Measurement conditions of surface roughness measuring instrument:
Reference length (cutoff value λc of roughness curve): 2.5 mm
Evaluation length (reference length (cutoff value λc) × 5): 12.5 mm
Feeding speed of stylus: 0.5 mm / s
Preliminary length: (cutoff value λc) × 2
Longitudinal magnification: 2000 times Lateral magnification: 10 times Usually, a cutoff value of 0.8 mm is often used, but in the present invention, the measurement was performed with the cutoff value set to 2.5 mm.
In addition, λa was calculated by an equation of λa = 2π × (Ra / tan (θa)).

(Interference fringes)
A black acrylic plate for preventing reflection of the back surface (light-transmitting substrate surface) of each transparent conductive laminate obtained in Examples and Comparative Examples through a transparent adhesive. Then, each transparent conductive laminate was irradiated with a sodium lamp from the surface of the conductive layer and visually observed, and the presence or absence of interference fringes was evaluated according to the following criteria.
A: No interference fringes were generated.
○: Some interference fringes were generated, but there was no problem.
X: Interference fringes were generated.
(Cloudiness)
The surface (light transmissive substrate surface) opposite to the undercoat layer of each transparent conductive laminate obtained in the examples and comparative examples was attached to a black acrylic plate via a transparent adhesive, and the table was placed in a dark room. The cloudiness was observed under a stand (3-wavelength fluorescent lamp tube) and evaluated according to the following criteria.
○: Whiteness was not observed.
X: Whiteness was observed.

(Anti-blocking evaluation)
The conductive layers of the transparent conductive laminates obtained in the examples and comparative examples were overlapped to produce an evaluation sample having a size of 5 cm × 5 cm.
About the produced sample for evaluation, using a blocking tester, the pressure condition is 3.0 kgf / cm ² , the test area is 3 cmφ, the wet temperature condition is 40 ° C., 90% RH, 30 hours. Judgment was made visually based on the following criteria.
○: No sticking.
X: There is sticking.

(Easy slip evaluation)
By superimposing the conductive layers of the transparent conductive laminates obtained in the examples and comparative examples, and rubbing the surfaces on which the conductive layers are formed surface-to-surface, and confirming slipperiness, the following criteria are satisfied: The slipperiness was evaluated.
○: Good slipperiness, no sticking, and good slipperiness.
X: The slipperiness was insufficient, sticking occurred in part, and the slipperiness was poor.

As shown in Table 1, the transparent conductive laminates according to the examples were good in all evaluations of interference fringes, white turbidity, anti-blocking properties, and slipperiness.
On the other hand, the transparent conductive laminates according to Comparative Example 1 and Comparative Example 5 cannot prevent interference fringes because the average inclination angle of the surface of the conductive layer or the low refractive index layer is too small. In addition, the evaluation of slipperiness was also inferior. The transparent conductive laminates according to Comparative Examples 2 to 4 and 6 to 8 were inferior in cloudiness because one or both of the average inclination angle and the ratio of Rp and Rv were too large.

A transparent conductive laminate produced in the same manner as the transparent conductive laminates according to Examples 1 to 4 and Comparative Examples 1 to 4 except that only the conductive layer was laminated on the undercoat layer (the above configuration (1)). In addition, the transparent conductive produced in the same manner as the transparent conductive laminates according to Examples 1 to 4 and Comparative Examples 1 to 4 except that only the high refractive index layer was laminated between the undercoat layer and the conductive layer. When the same evaluation as described above was performed on the conductive laminate (the above configuration (2)), the results were almost the same as those of the transparent conductive laminates according to Examples 1 to 4 and Comparative Examples 1 to 4.
Further, the transparent conductive laminates according to Examples 1 to 4 and Comparative Examples 1 to 4, the transparent conductive laminate of the above configuration (1), and the light transmittance of the transparent conductive laminate of the above configuration (2). A transparent conductive laminate (the above configuration (4)) in which another undercoat layer having the same composition as that of the undercoat layer is provided on the side opposite to the side on which the undercoat layer is provided, and the other undercoat A transparent conductive laminate (the above configuration (5)) provided with a high refractive index layer on the side opposite to the light-transmitting substrate side of the coat layer, and the light-transmitting substrate side of the other undercoat layer; For the transparent conductive laminate (the above configuration (6)) in which the high refractive index layer and the low refractive index layer were provided in this order on the opposite side, the same evaluation as described above was performed. The results were almost the same as those of the transparent conductive laminates according to Comparative Examples 1 to 4.
In addition, the conductive layer, the high refractive index layer and the low refractive index layer are not provided, and only the undercoat layer is formed on the light-transmitting substrate, similarly to the undercoat layer of the transparent conductive laminate according to each example and comparative example. When the laminated body provided as described above was manufactured, the surface of the undercoat layer had an uneven shape equivalent to that of each of the examples and comparative examples.

The transparent conductive laminate of the present invention can be suitably applied to touch panels, particularly capacitive touch panels.

Claims (13)

A transparent conductive laminate in which an undercoat layer and a conductive layer are laminated in this order on a light-transmitting substrate,
The conductive layer has a concavo-convex shape on the surface, and the concavo-convex shape is defined as Rp when the average inclination angle of the concavo-convex part is θa, the maximum peak height of the concavo-convex is Rp, and the maximum valley depth of the concavo-convex is Rv. The transparent conductive laminate is characterized in that the ratio of Rv to Rv is 1.5 or less, and the θa satisfies the following formula.
0.01 ° ≦ θa ≦ 0.10 ° The transparent conductive laminate according to claim 1, wherein the concavo-convex shape of the conductive layer satisfies the following formula when the arithmetic average roughness of the concavo-convex is Ra.
0.02 μm ≦ Ra ≦ 0.10 μm 3. The transparent conductive laminate according to claim 2, wherein the uneven shape of the conductive layer is such that an average wavelength λa represented by λa = 2π × (Ra / tan (θa)) satisfies the following formula.
200 μm ≦ λa ≦ 800 μm The transparent conductive laminate according to claim 1, wherein a high refractive index layer is laminated between the undercoat layer and the conductive layer. The transparent conductive laminate according to claim 1, 2, 3, or 4, wherein a high refractive index layer and a low refractive index layer are laminated between the undercoat layer and the conductive layer. The transparent conductive laminate according to claim 1, wherein the undercoat layer contains inorganic oxide fine particles and a binder resin. The transparent conductive laminate according to claim 6, wherein the inorganic oxide fine particles are hydrophobized inorganic oxide fine particles. The transparent conductive laminate according to claim 6 or 7, wherein the inorganic oxide fine particles form aggregates and are contained in the undercoat layer, and the average particle diameter of the aggregates is 100 nm to 2.0 µm. The transparent conductive laminate according to claim 1, further comprising another undercoat layer on the side opposite to the undercoat layer side of the light transmissive substrate. A transparent conductive laminate in which an undercoat layer and a high refractive index layer are laminated in this order on a light-transmitting substrate,
The high refractive index layer has a concavo-convex shape on the surface, and the concavo-convex shape has an average inclination angle of the concavo-convex portion as θa, a maximum peak height of the concavo-convex portion as Rp, and a maximum valley depth of the concavo-convex portion as Rv. The transparent conductive laminate is characterized in that the ratio of Rp and Rv is 1.5 or less, and the θa satisfies the following formula.
0.01 ° ≦ θa ≦ 0.10 ° The transparent conductive laminate according to claim 10, further comprising a low refractive index layer on a side surface opposite to the undercoat layer side of the high refractive index layer. A touch panel comprising the transparent conductive laminate according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11. An intermediate laminate for a touch panel for supporting a patterned conductive layer in which an undercoat layer is laminated on a light-transmitting substrate,
The undercoat layer has a concavo-convex shape on the surface, and the concavo-convex shape has an average inclination angle of the concavo-convex portion as θa, a maximum peak height of the concavo-convex portion as Rp, and a maximum valley depth of the concavo-convex portion as Rv. An intermediate laminate for a touch panel, wherein the ratio of Rp to Rv is 1.5 or less, and the θa satisfies the following formula.
0.01 ° ≦ θa ≦ 0.10 °

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