JP2013053241A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate in which the production process can be simplified, and that is excellent in bending properties, flexibility, and transparency, and to provide in detail, the laminate in which the adhesion of a carbon nanotube layer and a resin layer is high even if a surface treatment or the like is not performed to the carbon nanotube, and that can maintain the transparency even if the thickness of the resin layer increases.SOLUTION: The laminate includes: a carbon nanotube layer (a) of at least one layer; and a resin layer (b) that includes an acrylic block copolymer that includes at least one (meth)acrylic acid ester polymer block A in which the glass transition temperature is at least 20°C; and at least one (meth)acrylic acid ester polymer block B in which the glass transition temperature is at most 0°C, wherein the carbon nanotube layer (a) is formed by applying a carbon nanotube composition that is dispersed or dissolved to a dispersion medium or a solvent.

Description

  The present invention relates to a laminate comprising at least one carbon nanotube layer and a resin layer containing an acrylic block copolymer. The laminate of the present invention has conductivity and is useful as a constituent material for displays and electrode members.

Conventionally, a transparent conductive film in which a conductive material or a semiconductor material layer is formed on a transparent resin base material layer has been widely used for image display devices such as a touch panel, solar cell applications, and the like.
For example, Patent Literature 1 discloses a conductive laminate in which a base resin layer containing a urethane acrylate resin having a glycol skeleton and a conductive layer such as carbon nanotubes are laminated on a base material such as polyethylene terephthalate, and the like. It is disclosed that it is excellent in taste and input sensitivity. However, the conductive laminate needs to laminate a plurality of layers, and the manufacturing process is complicated.
In Patent Document 2, a cured film of a conductive curable resin composition containing a carbon nanotube, an acrylic polymer, a polymerizable monomer, and a photopolymerization initiator is laminated with a base material such as an acrylic resin. Moreover, the electroconductive laminated body which is excellent in transparency is disclosed. However, the conductive laminate is excellent in transparency, but lacks flexibility, flexibility, stretchability, etc., and has room for improvement.
In addition, these conductive laminates have problems such as poor adhesion between the conductive layer and the base material layer, or a special process such as surface treatment of a conductive substance is necessary for improving the adhesion. There is a problem that transparency cannot be maintained due to an increase in the thickness of the substrate such as a resin layer.

International Publication No. 2011/058898 JP 2006-328311 A International Publication No. 2009/145080 JP 2010-138222 A US Pat. No. 5,402,054 JP 2005-515281 A JP-A-11-335432

Macromol. Chem. Phys. 2000, 201, p. 1108 to 1114

  Thus, an object of the present invention is to provide a laminate that can simplify the production process, has excellent flexibility, flexibility, stretchability, and excellent transparency. Specifically, the present invention is to provide a laminate that has high adhesion between a carbon nanotube layer and a resin layer without performing surface treatment on the carbon nanotube, and can maintain transparency even when the thickness of the resin layer increases. .

According to the present invention, the above object is
[1] At least one carbon nanotube layer (a), at least one (meth) acrylic acid ester polymer block A having a glass transition temperature of 20 ° C. or higher, and (meth) acrylic acid having a glass transition temperature of 0 ° C. or lower. A laminate comprising a resin layer (b) containing an acrylic block copolymer containing at least one ester polymer block B, wherein the carbon nanotube layer (a) is dispersed or dissolved in a dispersion medium or solvent. A laminate formed by applying a carbon nanotube composition;
[2] The laminate of [1], wherein the total light transmittance of the resin layer (b) is 80% or more;
[3] The laminate of [1] or [2], wherein the resin layer (b) further contains an acrylic resin;
Is achieved by providing

  According to the present invention, a production process can be simplified, and a laminate having excellent flexibility, flexibility, stretchability, and excellent transparency can be obtained. Specifically, even if the carbon nanotube is not subjected to a surface treatment or the like, a laminate that has high adhesion between the carbon nanotube layer and the resin layer and can maintain transparency even when the thickness of the resin layer increases is obtained.

  The present invention is a laminate comprising at least one carbon nanotube layer (a) and a resin layer (b) containing a specific acrylic block copolymer.

The carbon nanotube layer (a) constituting the laminate of the present invention contains a carbon nanotube (hereinafter abbreviated as CNT) as a component.
The CNT layer (a) may be composed only of CNTs, or may contain a dispersion medium such as water or alcohol, a binder resin, or the like as long as the conductive performance can be maintained.

  As the CNT, a single-layer CNT (hereinafter referred to as “SWCNT”) in which one graphite sheet (graphene) is wound in a cylindrical shape, and a double-layer CNT (hereinafter referred to as “DWCNT”) in which two graphenes are wound in a concentric shape. And multilayer CNT (hereinafter referred to as “MWCNT”) in which a plurality of graphenes are concentrically wound. In the present invention, one of SWCNT, DWCNT, and MWCNT may be used alone, or two or more thereof may be used in combination. Among these, SWCNT and DWCNT are preferable from the viewpoint of excellent conductivity, and SWCNT is more preferable.

  Examples of CNT manufacturing methods include arc discharge, laser evaporation, and chemical vapor deposition (CVD). However, from the viewpoint of crystallinity, SWCNT obtained by a manufacturing method using an arc discharge method is preferable. And this thing is also easily available. In the case of the arc discharge method, for example, it can be manufactured by the method of Patent Document 5. When producing CNTs, catalyst metals such as nickel, iron, cobalt and yttrium also remain, so it is preferable to remove these impurities and purify them. In order to remove impurities, ultrasonic treatment is effective in addition to acid treatment with nitric acid, sulfuric acid, hydrofluoric acid, hydrochloric acid, phosphoric acid or a mixture thereof, or base treatment with tetramethylammonium hydroxide, ammonia, potassium hydroxide, etc. Further, it is more preferable to use filtration with a filter or separation by centrifugation in order to improve purity. In the case of acid treatment, acid treatment using nitric acid or a mixed acid of nitric acid and sulfuric acid is preferable. In the case of filtration, various filtration methods such as suction filtration, pressure filtration, and cross flow filtration can be used.

  Although there is no strict limitation on the thickness of the CNT layer (a), the thickness of the CNT layer (a) is usually preferably 5 nm to 300 nm, more preferably 30 nm to 250 nm. If the thickness is less than 5 nm, it may be difficult to form a continuous film having desired conductivity. When the CNT layer (a) exceeds 300 nm, the transparency tends to be inferior.

  The CNT layer (a) is formed by applying a CNT composition dispersed or dissolved in a dispersion medium or a solvent. At the time of formation, the resin layer (b) may be applied directly, or the CNT layer (a) is formed on the substrate different from the resin layer (b) by the above-described method, and the resin layer ( You may transfer and laminate to b). Here, the CNT composition is a composition containing CNT, may be composed of only CNT, and may contain other components such as a binder resin and a surfactant.

  As the method of coating, a spin coater, bar coater, roll coater, die coater, or the like obtained by dispersing or dissolving a CNT composition in a dispersion medium or solvent on a substrate such as a silicon wafer or glass or a resin layer (b). There are methods such as coating using a coater, comma coater, spray coating, dipping coating and the like. The CNT layer (a) can be obtained by drying the dispersion medium or solvent. When a polymerizable monomer is used as a dispersion medium or a solvent, by adding a polymerization initiator, it can be cured by UV or heat after application to form the CNT layer (a).

  As the dispersion medium, at least one selected from the group of water, alcohol-based dispersion medium, ketone-based dispersion medium, amide-based dispersion medium, ester-based dispersion medium, aprotic dispersion medium, and the like can be used. Further, as the binder resin, at least one selected from the group of styrene resin, ester resin, ether resin, polycarbonate resin, (meth) acrylic acid ester resin and the like can be used.

The resin layer (b) contains a specific acrylic block copolymer.
The acrylic block copolymer comprises at least one (meth) acrylic ester polymer block A having a glass transition temperature of 20 ° C. or higher and a (meth) acrylic ester polymer block B having a glass transition temperature of 0 ° C. or lower. It is a block copolymer containing at least one.

  The polymer block A is a (meth) acrylic acid ester polymer having a glass transition temperature of 20 ° C. or higher, and its structural unit is mainly composed of (meth) acrylic acid ester. The (meth) acrylic acid ester constituting the polymer block A is not particularly limited as long as it is a (meth) acrylic acid ester having a glass transition temperature of 20 ° C. or higher. For example, methyl methacrylate, methacrylic acid Methacrylic acid esters such as ethyl, propyl methacrylate, isopropyl methacrylate, t-butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate; acrylic acid such as methyl acrylate, t-butyl acrylate, cyclohexyl acrylate, isobornyl acrylate Examples include esters. The said methacrylic acid ester or acrylic acid ester may be used individually by 1 type, and may mix and use 2 or more types.

  The polymer block B is a (meth) acrylic acid ester polymer having a glass transition temperature of 0 ° C. or lower, and its structural unit is mainly composed of (meth) acrylic acid ester. The (meth) acrylic acid ester constituting the polymer block B is not particularly limited as long as the glass transition temperature of the homopolymer is 0 ° C. or lower. For example, n-butyl methacrylate, 2-ethylhexyl methacrylate, methacryl Methacrylic acid esters such as dodecyl acid, benzyl methacrylate, phenoxyethyl methacrylate, 2-methoxyethyl methacrylate; ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, acrylic acid Examples thereof include acrylic acid esters such as dodecyl, benzyl acrylate, phenoxyethyl acrylate, and 2-methoxyethyl acrylate. The said (meth) acrylic acid ester may be used individually by 1 type, and may mix and use 2 or more types.

  The polymer block A may contain a structural unit derived from a (meth) acrylic acid ester constituting the polymer block B as long as the properties of the polymer block A are not impaired. In the block B, the structural unit derived from the (meth) acrylic acid ester which comprises the polymer block A may be contained in the range which does not impair the characteristic of the polymer block B.

  In addition to the above (meth) acrylic acid ester, the polymer block A and the polymer block B may be copolymerized with other monomers as necessary, as long as the properties of the respective polymer blocks are not impaired. Good. Examples of such other monomers include methacrylic acid; methacrylic acid ester having a reactive group such as glycidyl methacrylate, allyl methacrylate, 2-hydroxyethyl methacrylate, trimethoxysilylpropyl methacrylate, N-isopropylamide methacrylate; Acrylic acid: Glycidyl acrylate, allyl acrylate, 2-hydroxyethyl acrylate, trimethoxysilylpropyl acrylate, acrylic acid N-isopropylamide, and other acrylic acid esters; styrene, α-methylstyrene, p- Aromatic vinyl compounds such as methylstyrene; nitriles such as acrylonitrile and methacrylonitrile; vinyl acetate; olefins such as ethylene, propylene and 1-butene; vinyl chloride; vinylidene chloride; vinyl fluoride; Alkylidene; butadiene, a conjugated diene such as isoprene; and maleic anhydride and the like.

  The mass ratio between the polymer block A and the polymer block B of the acrylic block copolymer is not particularly limited, but usually, A / B = 15/85 to 85/15 is preferable, and 25/75 to 75/25. Is more preferable, and 40/60 to 70/30 is more preferable. When the ratio of the polymer block A is smaller than 15% by mass, the handling property of the acrylic block copolymer tends to be inferior. When the ratio of the polymer block A is larger than 85% by mass, the flexibility of the resin layer (b) tends to be insufficient.

  The weight average molecular weight of the acrylic block copolymer is preferably 10,000 to 500,000 and more preferably 30,000 to 200,000 from the viewpoint of improving the extrusion moldability of the resin layer (b). When the weight average molecular weight of the acrylic block copolymer is smaller than 10,000, for example, sufficient melt tension cannot be maintained in melt extrusion molding, thickness accuracy is lowered, and a good resin layer (b) is hardly obtained. . On the other hand, when it is larger than 500,000, for example, the surface of the resin layer (b) obtained by melt-extrusion molding tends to generate unevenness due to unmelted material (high molecular weight body). The molecular weight distribution (ratio of weight average molecular weight / number average molecular weight) is preferably 1.01-1.80, more preferably 1.01-1.50, from the viewpoint of improving the transparency of the resin layer (b). preferable.

  As a form of said acrylic block copolymer, the diblock copolymer represented by AB, the triblock copolymer represented by ABA or BAB, AB Examples thereof include a tetrablock copolymer represented by -A-B. Among these, a triblock copolymer or a mixture of a triblock copolymer and a diblock copolymer is preferable.

  As a manufacturing method of said acrylic block copolymer, living polymerization is preferable. Examples of living polymerization include living radical polymerization, living cationic polymerization, and living anion polymerization, but living radical polymerization and living anion polymerization are more preferable. Examples of the living radical polymerization method include a control radical polymerization method (CRP) using a stable nitroxy group compound as described in Patent Document 6 and an atom transfer radical polymerization method (ATRP) as described in Non-Patent Document 1. Examples of the living anion polymerization method include a polymerization method using an organoaluminum compound as described in Patent Document 7, a polymerization method using an organic samarium complex, and a polymerization method using an alkoxy lithium such as lithium chloride or lithium methoxyethoxide. . Among these, the atom transfer radical polymerization method and the living anion polymerization method using an organoaluminum compound are preferable, the control of the molecular weight and the molecular weight distribution is excellent, the unreacted monomer content and the oligomer component are small, and the resulting acrylic block copolymer. The living anionic polymerization method using an organoaluminum compound is more preferable because of its excellent transparency.

  Although the resin layer (b) may be comprised only from the said acrylic block copolymer, it may be comprised from the resin composition containing this acrylic block copolymer. In that case, 15-100 mass% is preferable, as for the ratio of the acrylic type block copolymer in a resin composition, 30-100 mass% is more preferable, and 50-100 mass% is further more preferable. In addition to the acrylic block copolymer, other components may include other polymers, polymer processing aids, colorants, tackifying resins, plasticizers, fillers, antioxidants, anti-sticking agents, etc. Can be mentioned.

  Examples of other polymers include methacrylic acid ester polymers. Here, in this specification, “methacrylic acid ester polymer” means methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, cyclohexyl methacrylate, It means a (co) polymer of a methacrylic acid ester having no functional group such as 2-ethylhexyl methacrylate, dodecyl methacrylate, benzyl methacrylate, phenoxyethyl methacrylate, and isobornyl methacrylate. However, such methacrylic acid ester polymers include, in addition to the above-mentioned methacrylic acid esters, 2-methoxyethyl methacrylate, glycidyl methacrylate, allyl methacrylate, 2-hydroxyethyl methacrylate, trimethoxysilylpropyl methacrylate, methacrylic acid. Methacrylic acid ester having a functional group such as acid N-isopropylamide; acrylic acid; methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, benzyl acrylate, phenoxyethyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, glycidyl acrylate, allyl acrylate, acrylic Acrylic acid esters such as 2-hydroxyethyl acrylate, trimethoxysilylpropyl acrylate, N-isopropylamide acrylate; aromatic vinyl compounds such as styrene, α-methylstyrene, p-methylstyrene; acrylonitrile, methacrylonitrile, etc. Nitriles; vinyl acetate; olefins such as ethylene, propylene and 1-butene; vinyl chloride; vinylidene chloride; vinyl fluoride; vinylidene fluoride; conjugated dienes such as butadiene and isoprene; Good.

  When the resin layer (b) is composed of a resin composition containing the methacrylic ester polymer in addition to the acrylic block copolymer, the methacrylic ester polymer is contained in the resin composition. The amount is preferably 85% by mass or less, more preferably 70% by mass or less, and further preferably 50% by mass or less.

  The thickness of the resin layer (b) is preferably 1 μm to 1000 μm, more preferably 30 μm to 200 μm, from the viewpoints of flexibility, weight and thickness of the member made of the laminate of the present invention.

  The tensile elastic modulus of the resin layer (b) is preferably 1 to 2000 MPa, more preferably 10 to 1000 MPa, from the viewpoints of flexibility and adhesion with the CNT layer (a).

The resin layer (b) can be produced by, for example, a hot melt molding method, a solution casting method, or the like.
The hot melt molding method is a method of molding by melting a resin by heat, and examples thereof include a hot melt coating method, a T-die extrusion method, an inflation method, and a calendar molding method. Among these, the T die method or the inflation method is preferable from the viewpoint of productivity, thickness accuracy, cost, and the like, and the T die method is more preferable.

  When the resin layer (b) is produced by the T-die method, for example, a resin composition containing an acrylic block copolymer is melted in an extruder, and a sheet or film is formed from the T-die provided in the extruder. The extruded sheet or film is taken into close contact with at least one cooling drum.

  As the solution casting method, a general method used for manufacturing a film-like or sheet-like member can be applied. For example, a heat-resistant material such as polyethylene terephthalate or a flat plate or roll such as a steel belt is used as a support, and an acrylic block copolymer or acrylic is used on these using a bar coater, roll coater, die coater, comma coater, or the like. Examples include a method in which a solution obtained by dissolving a resin composition containing a system block copolymer in a solvent is applied, and the solvent is removed by drying.

  The method for removing the solvent by drying is not particularly limited, and a conventionally known method can be used, but it is preferable to perform drying in a plurality of stages. When drying is performed in a plurality of stages, the first stage of drying is performed at a relatively low temperature in order to suppress foaming due to rapid volatilization of the solvent. A method of drying at a high temperature to remove the solvent is more preferable.

  In the solution casting method, the solvent used for dissolving the acrylic block copolymer or the resin composition containing the acrylic block copolymer is, for example, toluene, ethyl acetate, ethylbenzene, methylene chloride, chloroform, tetrahydrofuran, methyl ethyl ketone, Examples thereof include dimethyl sulfoxide and a toluene-ethanol mixed solvent. Of these, toluene, ethylbenzene, ethyl acetate, and methyl ethyl ketone are preferable.

  The concentration of the acrylic block copolymer or the resin composition containing the acrylic block copolymer in the above solution is appropriately determined in consideration of the solubility in the solvent, the viscosity of the resulting solution, etc., but the preferred lower limit value. Is 5% by mass, and a preferable upper limit is 50% by mass.

  As a method for producing the laminate of the present invention in which the CNT layer (a) and the resin layer (b) are laminated, as described above in the method for forming the CNT layer (a), the CNT layer is directly formed on the resin layer (b). Examples thereof include a method of forming (a) and a method of transferring the CNT layer (a) to the resin layer (b) after forming the CNT layer (a) on another substrate.

  The laminate of the present invention may have other layers such as an adhesive layer and a cushion layer between the CNT layer (a) and the resin layer (b), or the CNT layer (a) or the resin layer ( You may have other layers, such as another resin layer and a glass substrate layer, in the surface of the side which is not facing each other of b).

  The laminated body of this invention can be used conveniently as electrode members, such as displays, such as a touch panel, a liquid crystal display, organic EL, electronic paper, and a module of a solar cell.

  Hereinafter, the present invention will be described with reference to examples and the like, but the present invention is not limited to these examples.

(1) Weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of an acrylic block copolymer
It was determined as a standard polystyrene equivalent molecular weight by gel permeation chromatography (hereinafter abbreviated as GPC).
-Equipment: GPC equipment "HLC-8020" manufactured by Tosoh Corporation
Separation column: “TSKgel GMHXL”, “G4000HXL” and “G5000HXL” manufactured by Tosoh Corporation are connected in series. Eluent: Tetrahydrofuran Eluent flow rate: 1.0 ml / min Column temperature: 40 ° C.
・ Detection method: Differential refractive index (RI)
(2) PMMA content in acrylic block copolymer (content of methyl methacrylate units, mass%)
^It was determined by ¹ H-NMR measurement.
(3) Tensile elastic modulus A polymer or a resin composition (hereinafter referred to as raw material resin) constituting the resin layers (b-I) to (b-IV) used in the following examples or comparative examples is a press molding machine. According to the method described in ISO 527-3, a 1 mm thick sheet molded at an appropriate temperature of each raw material resin was measured at 23 ° C. under a tensile speed of 300 mm / min.
(4) Total light transmittance of laminated body It measured according to JISK7361-1 with the haze meter (Nippon Denshoku Industries NDH5000).
(5) Surface resistance value of laminated body It measured according to JISK7194 with the resistivity meter (Mitsubishi Chemical Analytic Loresta EP).
(6) Adhesion between CNT layer (a) and resin layer (b) Adhesion between the CNT layer (a) and the resin layer (b) was measured according to a cross-cut test: JIS K 5400. In JIS K 5400, if no peeling occurs in the grid, it is evaluated as 10 points, and is preferably 10 points. Moreover, when 65% or more of all the square areas peeled, it evaluated as 0 points | pieces.

[Production of Resin Layer (b) Raw Material Resin (Composition) and Resin Layer (b)]
Details of the production of the raw material resins (compositions) (I) to (IV) and the resin layers (b-I) to (b-IV) used in Examples and Comparative Examples are shown below.

[Raw resin (I): Acrylic block copolymer]
In the presence of isobutylbis (2,6-di-tert-butyl-4-methylphenoxy) aluminum, a monomer (methyl methacrylate, acrylic acid) corresponding to each block in toluene using sec-butyllithium as a polymerization initiator. n-Butyl, methyl methacrylate) are sequentially added to perform living anion polymerization, and after removing the aluminum and lithium used, an acrylic triblock copolymer (raw resin (I)) is removed by a devolatilizing twin-screw extruder. Got.
The structure of the obtained raw resin (I) is a triblock copolymer of methyl methacrylate polymer block (PMMA) -n-butyl acrylate polymer block (PnBA) -methyl methacrylate polymer block (PMMA). The PMMA content was 44 mass%, the weight average molecular weight (Mw) was 63,000, and the molecular weight distribution (weight average molecular weight / number average molecular weight) was 1.15. Moreover, the tensile elasticity modulus of raw material resin (I) was 20 Mpa.

[Raw material resin (II): Acrylic triblock copolymer resin composition]
40 parts by mass of the raw material resin (I) obtained above and 60 parts by mass of a commercially available methacrylic ester polymer: “Parapet GF: manufactured by Kuraray Co., Ltd.” were melt-kneaded at 210 ° C. using a twin screw extruder. Thus, an acrylic triblock copolymer resin composition (raw resin (II)) was obtained. The tensile modulus of the raw material resin (II) was 900 MPa.

[Raw material resin (III): Acrylic triblock copolymer resin composition]
67 parts by mass of the raw material resin (I) and 33 parts by mass of “Parapet GF: manufactured by Kuraray Co., Ltd.” were melt-kneaded at 210 ° C. using a twin-screw extruder to obtain an acrylic block copolymer resin composition (raw material resin). (III)) was obtained. The tensile modulus of the raw material resin (III) was 300 MPa.

[Raw Material Resin (IV): Composition of Multilayer Crosslinked Rubber Particles and Methacrylate Polymer]
(1) Sodium dodecylbenzenesulfonate as an aqueous phase emulsifier, potassium peroxodisulfate as a polymerization initiator, polyoxyethylene alkyl sodium phosphate as a monomer phase emulsifier, 30 parts by mass of n-butyl acrylate, methyl methacrylate 14 The first layer was formed by emulsion polymerization of parts by mass, 6 parts by mass of styrene, and 0.2 parts by mass of allyl methacrylate. Next, 20 parts by mass of n-butyl acrylate, 10 parts by mass of methyl methacrylate, 4 parts by mass of styrene and 0.1 part by mass of allyl methacrylate were dropped and polymerized to form a second layer. Furthermore, 24 parts by mass of methyl methacrylate, 1.3 parts by mass of methyl acrylate, and 0.25 part by mass of n-octyl mercaptan were subjected to dropwise polymerization to form a third layer. The obtained latex was cooled to −30 ° C. for 24 hours for freeze aggregation, and then the aggregate was melted and taken out. It dried under reduced pressure at 50 degreeC for 2 days, and obtained the powdery three-layer type multilayer structure crosslinked rubber particle.
(2) 20 parts by mass of the multilayered crosslinked rubber particles obtained above and 80 parts by mass of “Parapet GF: manufactured by Kuraray Co., Ltd.” were melt-kneaded at 210 ° C. using a twin screw extruder, and the raw resin (IV )
The tensile modulus of elasticity of the obtained raw material resin (IV) was 2300 MPa.

[Production of Resin Layers (b-I) to (b-IV)]
The raw material resins (I) to (IV) were subjected to a cylinder temperature and a T-die extruder using a φ40 mm single screw extruder (main extruder) and a φ22 mm single screw extruder (sub extruder). Extrusion was performed at a die temperature of 220 ° C., followed by cooling so that one surface was in contact with the polishing roll, and resin layers (b-I) to (b-IV) having a thickness of 0.1 mm were produced.

Example 1
SWCNT synthesized by arc discharge was purified by processes including acid treatment, water washing, centrifugation, and filtration. Next, 0.2 wt% aqueous solution of sodium dodecylbenzenesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a surfactant is added to the purified SWCNT, and the CNTs are dispersed with a chip-type ultrasonic wave and centrifuged to obtain a SWCNT dispersion. It was. A coating aid BYK345 (manufactured by BYK Japan) was added to the obtained SWCNT dispersion in an amount of 0.1 wt% as a solid content, and the mixture was sufficiently stirred to obtain a SWCNT dispersion coating liquid (SWCNT: 2,300 ppm).
The obtained SWCNT dispersion coating liquid is coated on the resin layer (b-II) with a wire bar so that the wet film thickness (film thickness including the dispersion medium before drying) is 27.4 μm. And dried at 80 ° C. for 2 minutes. Then, it wash | cleaned with methanol and dried again at 80 degreeC for 1 minute, and the laminated body which has SWCNT as an electroconductive layer was obtained. The obtained laminate had a total light transmittance of 86.7%, a surface resistance value of 940Ω / □, and an adhesion of 10 points.

Example 2
The same operation as in Example 1 was performed except that the wet film thickness of the SWCNT dispersion coating liquid was changed to 36.6 μm in Example 1. The obtained laminate had a total light transmittance of 84.0%, a surface resistance value of 600Ω / □, and an adhesion of 10 points.

Example 3
The same operation as in Example 1 was performed except that the wet film thickness of the SWCNT dispersion coating liquid was changed to 50.3 μm in Example 1. The obtained laminate had a total light transmittance of 80.7%, a surface resistance value of 340Ω / □, and an adhesion of 10 points.

Example 4
The same operation as in Example 1 was performed except that the resin layer (b-III) was used instead of the resin layer (b-II) in Example 1. The obtained laminate had a total light transmittance of 87.0%, a surface resistance value of 1,610 Ω / □, and an adhesion of 10 points.

Example 5
The same operation as in Example 2 was performed except that the resin layer (b-III) was used instead of the resin layer (b-II) in Example 2. The obtained laminate had a total light transmittance of 84.2%, a surface resistance value of 880Ω / □, and an adhesion of 10 points.

Example 6
The same operation as in Example 3 was performed except that the resin layer (b-III) was used instead of the resin layer (b-II) in Example 3. The obtained laminate had a total light transmittance of 83.4%, a surface resistance value of 840Ω / □, and an adhesion of 10 points.

Example 7
The same operation as in Example 3 was performed except that the resin layer (b-I) was used instead of the resin layer (b-II) in Example 3. The obtained laminate had a total light transmittance of 85.1%, a surface resistance value of 1,050Ω / □, and an adhesion of 10 points.

Comparative Example 1
The same operation as in Example 2 was performed except that the resin layer (b-IV) was used instead of the resin layer (b-II) in Example 2. The obtained laminate had a total light transmittance of 86.2%, a surface resistance value of 510Ω / □, and an adhesion of 0 points.

In Comparative Example 1 using the resin layer (b-IV) having the same composition as that of a general acrylic film, there is no problem in terms of total light transmittance and surface resistance, but the adhesion of the SWCNT layer (a). Was bad. Further, the end face was chipped during cutting, and a good product could not be obtained.
On the other hand, Examples 1-7 are excellent in adhesiveness with resin layer (b-I)-(b-III) of SWCNT layer (a). Further, there was no chipping defect on the end face during cutting, and the total light transmittance was maintained at 80% or more even after application of the conductive layer, and the transparency was excellent. Moreover, the surface resistance value of Examples 1-7 was a value which can fully be applied to a touch panel member etc. In Example 7, the surface opposite to the resin layer (b-I) having the SWCNT layer (a) had adhesiveness, and could be directly adhered to another adherend.

  The laminate obtained in the present invention can be suitably used as an electrode member for a display such as a touch panel, a liquid crystal display, an organic EL, or an electronic paper, or a module of a solar cell.

Claims (3)

  At least one carbon nanotube layer (a), at least one (meth) acrylic ester polymer block A having a glass transition temperature of 20 ° C. or higher, and a (meth) acrylic ester polymer having a glass transition temperature of 0 ° C. or lower. Carbon nanotubes comprising a resin layer (b) containing an acrylic block copolymer containing at least one block B, wherein the carbon nanotube layer (a) is dispersed or dissolved in a dispersion medium or solvent A laminate formed by applying a composition.   The laminate according to claim 1, wherein the total light transmittance of the resin layer (b) is 80% or more.   The laminate according to claim 1 or 2, wherein the resin layer (b) further contains an acrylic resin.