JP2015056337A - Transparent conductive film and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent conductive film for a display element, which exhibits small warpage and is excellent in conductivity and transparency.SOLUTION: In the transparent conductive film, an ITO-containing transparent conductive membrane formed by sputtering is provided on one side of a film substrate on both sides of which hard coat layers containing inorganic particles and an organic component are provided and which contains a fumaric acid diester resin. The transparent conductive film has a resistivity of 2×10Ω cm or less and a total light transmittance of 80% or more.

Description

  The present invention relates to a transparent conductive film for display elements.

  Flat panel displays typified by liquid crystal displays, organic EL displays, and plasma displays are widely used as the most important display devices in the multimedia society, from mobile phones to computer monitors, notebook computers, and televisions. There is an urgent need to improve the characteristics of transparent electrodes or transparent conductive films used in these display elements.

  In general, such a transparent electrode is obtained by forming a transparent conductive film on a glass substrate. However, a glass material used as a substrate has problems such as being easily broken, having a large specific gravity, poor flexibility and workability. Recently, an optical film made of a transparent resin has been studied as a substitute for and replacing the drawbacks of these glass materials. The optical film has advantages such as excellent impact resistance, flexibility, light weight, and workability. By using an optical film, it is possible to make the display thinner, lighter, and more formable, and it is expected that the application to thin televisions, notebook personal computers, mobile terminals, mobile phones, etc. will be rapidly developed.

  At present, ITO films that are excellent in conductivity and transparency, easy in pattern processability, and excellent in durability are mainly used as transparent conductive films formed on glass substrates. As a method for forming the ITO film, a vacuum deposition method, a sputtering method, an ion plating method and the like are known. As a method of forming an ITO film for a display element, a sputtering method is often used because of excellent film uniformity, good reproducibility of the film composition, and high productivity.

  On the other hand, a transparent conductive film in which a transparent conductive film is formed on an optical film is not used for a display element, but is often used for a touch panel. As a transparent conductive film, an ITO film is mainly used. Here, a certain level of heat resistance is required for the transparent conductive film used for the touch panel, but conventionally known optical films do not have sufficient heat resistance, and are transparent conductive for display elements. There was a problem that application as a film was difficult. For example, a polyethylene terephthalate (PET) film is used as an optical film, and after forming an amorphous ITO film on the film, annealing is performed for several hours to several tens of hours at a temperature of about 150 ° C. A transparent conductive film obtained by crystallizing ITO has been proposed (see, for example, Patent Document 1). In Patent Document 1, the film thickness of ITO is 10 to 50 nm, and for display elements that require low sheet resistance, the film thickness of ITO needs to be 100 nm or more, so the film is deformed during annealing at a high temperature of 200 ° C. or more. There was a problem to do. In addition, a transparent conductive film in which a transparent conductive film is formed in a temperature range of −50 ° C. to + 10 ° C. using a polyarylate film having a glass transition temperature of 180 ° C. or more has been proposed (for example, a patent Reference 2). In patent document 2, it does not crystallize by heat-treating after forming the ITO film at room temperature, but it is durable by transferring to crystalline by simultaneously heat-treating when forming the ITO film on the film. Although a high ITO film is obtained, the transparent conductive film has a problem that a thermal expansion coefficient is high and a large warp occurs due to shrinkage after heating.

  On the other hand, in order to obtain an optical film excellent in transparency, optical characteristics, etc., a film using a fumaric acid diester resin has been proposed, and an optical film for display made of a crosslinked fumaric acid diester resin has been proposed. (For example, refer to Patent Document 3). However, the film described in Patent Document 3 has insufficient adhesion after repeated heat treatment, and a film having excellent adhesion has been demanded.

  Also, a fumaric acid diester provided with a hard coat layer composed of inorganic particles and an organic component on at least one side in order to obtain a transparent conductive film for a display element having excellent adhesion, conductivity and transparency after repeated heat treatment A transparent conductive film in which a transparent conductive film is provided on a film substrate made of a resin is proposed (see, for example, Patent Document 4).

  Furthermore, in order to obtain a plastic substrate film for a display element having excellent heat resistance, hygroscopicity and optical characteristics, and a small coefficient of thermal expansion, fumaric acid provided with a hard coat layer composed of inorganic particles and organic components on both sides A transparent film made of a diester resin, having an inorganic layer of 1.3 to 4.0 μm on both sides of the transparent film, a thermal expansion coefficient of 30 ppm or less, and a total light transmittance of 85% or more A laminated film has been proposed (see, for example, Patent Document 5).

  The films described in Patent Document 4 and Patent Document 5 are excellent in various performances, but are less warped and used for display elements from the viewpoint of demands for thinning, lightening, and morphing of displays. There is a need for transparent conductive films having a lower resistivity.

Japanese Patent Laid-Open No. 08-64034 Japanese Patent Laid-Open No. 2000-255016 JP 2006-249318 A JP 2009-143026 A JP 2011-1116054 A

  The present invention has been made in view of the above-mentioned facts, and the object of the present invention is to form a film with an amorphous structure and heat it to transition to a crystal structure, thereby reducing warping, conductivity and transparency. It is providing the transparent conductive film for display elements which is excellent in property.

  As a result of intensive studies on the above problems, the present inventors have found that a transparent conductive film comprising a fumaric acid diester resin, a hard coat layer, and a transparent conductive film that has been transformed into a crystalline structure by heating it with an amorphous structure and heating it. As a result, it was found that a functional film solves the above-mentioned problems, and the present invention has been completed.

That is, in the present invention, a transparent conductive film containing ITO formed by sputtering is provided on one side of a film substrate containing a fumaric acid diester resin provided with a hard coat layer containing inorganic particles and an organic component on both sides. The present invention relates to a transparent conductive film having a resistivity of 2 × 10 ⁻⁴ Ω · cm or less and a total light transmittance of 80% or more.

  Hereinafter, the transparent conductive film of the present invention will be described in detail.

  The transparent conductive film of the present invention is a transparent conductive film in which a transparent conductive film containing ITO formed by sputtering is provided on one side of a film substrate provided with a hard coat layer.

  The film substrate of the present invention is a film substrate containing a fumaric acid diester resin.

  The fumaric acid distel-based resin of the present invention preferably contains 50 mol% or more, more preferably 70 mol% or more, and more preferably 80 mol% or more of the fumaric acid diester residue unit represented by the following general formula (1). It is particularly preferable that the content is 90 mol% or more.

（ここで、Ｒ_１、Ｒ_２はそれぞれ独立して炭素数３〜１２の分岐状アルキル基又は環状アルキル基を示す。）
ここで、一般式（１）で示されるフマル酸ジエステル残基単位のエステル置換基であるＲ_１、Ｒ_２は、それぞれ独立して、炭素数３〜１２の分岐アルキル基又は環状アルキル基であり、フッ素，塩素などのハロゲン基、エーテル基、エステル基若しくはアミノ基で置換されていても良い。炭素数３〜１２の分岐状アルキル基としては、例えば、イソプロピル基、ｓ−ブチル基、ｔ−ブチル基、ｓ−ペンチル基、ｔ−ペンチル基、ｓ−ヘキシル基、ｔ−ヘキシル基等が挙げられ、炭素数３〜１２の環状アルキル基としては、例えば、シクロプロピル基、シクロペンチル基、シクロヘキシル基等が挙げられる。その中でも耐熱性、機械特性により優れた透明導電性フィルムとなることから、イソプロピル基、ｓ−ブチル基、ｔ−ブチル基、シクロペンチル基、シクロヘキシル基が好ましく、特に耐熱性、機械特性のバランスに優れた透明導電性フィルムとなることから、イソプロピル基がさらに好ましい。

(Here, R ₁ and R ₂ each independently represents a branched or cyclic alkyl group having 3 to 12 carbon atoms.)
Here, R ₁ and R ₂ which are ester substituents of the fumaric acid diester residue unit represented by the general formula (1) are each independently a branched alkyl group or a cyclic alkyl group having 3 to 12 carbon atoms. , A halogen group such as fluorine and chlorine, an ether group, an ester group or an amino group. Examples of the branched alkyl group having 3 to 12 carbon atoms include isopropyl group, s-butyl group, t-butyl group, s-pentyl group, t-pentyl group, s-hexyl group, and t-hexyl group. Examples of the cyclic alkyl group having 3 to 12 carbon atoms include a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group. Among them, an isopropyl group, s-butyl group, t-butyl group, cyclopentyl group, and cyclohexyl group are preferable because the transparent conductive film is excellent in heat resistance and mechanical characteristics, and particularly excellent in balance between heat resistance and mechanical characteristics. An isopropyl group is more preferable because it becomes a transparent conductive film.

  As the fumaric acid diester residue unit represented by the general formula (1), specifically, diisopropyl fumarate residue, di-s-butyl fumarate residue, di-t-butyl fumarate residue, fumaric acid Di-s-pentyl residue, di-t-pentyl fumarate residue, di-s-hexyl fumarate residue, di-t-hexyl fumarate residue, dicyclopropyl fumarate residue, dicyclopentyl fumarate Residue, dicyclohexyl fumarate residue, etc. Among them, diisopropyl fumarate residue, di-s-butyl fumarate residue, di-t-butyl fumarate residue, dicyclopentyl fumarate residue, fumarate An acid dicyclohexyl residue is preferable, and a diisopropyl fumarate residue is more preferable.

  The fumaric acid diester residue unit containing 50 mol% or more of the fumaric acid diester residue unit represented by the general formula (1) is substantially 50 mol% or more of the fumaric acid diester residue unit represented by the general formula (1). , And a resin containing 50 mol% or less of a residue unit consisting of a monomer copolymerizable with fumaric acid diesters, and as a residue unit consisting of a monomer copolymerizable with fumaric acid diesters, for example, Styrene residues such as styrene residues and α-methylstyrene residues; acrylic acid residues; methyl acrylate residues, ethyl acrylate residues, butyl acrylate residues, acrylic acid-3-ethyl-3- Acrylic acid ester residues such as oxetanylmethyl residues; methacrylic acid residues; methyl methacrylate residues, ethyl methacrylate residues, butyl methacrylate residues, methacrylic acid-3 Methacrylic acid ester residues such as ethyl-3-oxetanylmethyl residue; Vinyl ester residues such as vinyl acetate residue and vinyl propionate residue; Acrylonitrile residue; Methacrylonitrile residue; Ethylene residue, Propylene One type or two or more types of olefin residues such as residues can be mentioned.

The fumaric acid diester resin used in the present invention has a number average molecular weight (Mn) in terms of standard polystyrene obtained from an elution curve measured by gel permeation chromatography (GPC), which is superior in mechanical properties, and at the time of film formation. 1 × 10 ⁴ or more is preferable, and 2 × 10 ⁴ or more and 2 × 10 ⁵ or less are more preferable.

  The fumaric acid diester resin in the present invention may be produced by any method as long as the fumaric acid diester resin can be obtained. For example, the fumaric acid diester resin may be used together with fumaric acid diesters and, in some cases, fumaric acid diesters. It can be produced by carrying out radical polymerization using a polymerizable monomer in combination. Examples of fumaric acid diesters include diisopropyl fumarate, di-s-butyl fumarate, di-t-butyl fumarate, di-s-pentyl fumarate, di-t-pentyl fumarate, and fumaric acid. Di-s-hexyl, di-t-hexyl fumarate, dicyclopropyl fumarate, dicyclopentyl fumarate, dicyclohexyl fumarate, and the like. Examples of the monomer copolymerizable with fumarate diester include styrene. Styrenes such as α-methylstyrene; acrylic acid; acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, acrylic acid-3-ethyl-3-oxetanylmethyl; methacrylic acid; methyl methacrylate; Ethyl methacrylate, butyl methacrylate, methacrylic acid-3-ethyl-3-oxetanyl Methacrylic acid esters such as chill; vinyl acetate, vinyl esters such as vinyl propionate and the like; acrylonitrile; methacrylonitrile; ethylene, olefins such as propylene, can be cited one or more equal.

  The radical polymerization method is not particularly limited as long as the fumaric acid diester resin of the present invention can be produced. For example, any of bulk polymerization method, solution polymerization method, suspension polymerization method, precipitation polymerization method and emulsion polymerization method can be used. Can be adopted.

  Examples of the polymerization initiator used in the radical polymerization method include benzoyl peroxide, lauryl peroxide, octanoyl peroxide, acetyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide, and dicumyl peroxide. Organic peroxides such as oxide, t-butylperoxyacetate, t-butylperoxybenzoate, t-butylperoxypivalate; 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2 ′ -Azo such as azobis (2-butyronitrile), 2,2'-azobisisobutyronitrile, dimethyl-2,2'-azobisisobutyrate, 1,1'-azobis (cyclohexane-1-carbonitrile) A system initiator is mentioned.

  The solvent that can be used in the solution polymerization method or the precipitation polymerization method is not particularly limited. For example, aromatic solvents such as benzene, toluene, and xylene; alcohol solvents such as methanol, ethanol, propyl alcohol, and butyl alcohol; cyclohexane; Tetrahydrofuran; acetone; methyl ethyl ketone; dimethylformamide; isopropyl acetate; water, and a mixed solvent thereof.

  Moreover, the polymerization temperature at the time of performing radical polymerization can be suitably set according to the decomposition temperature of a polymerization initiator, and generally it is preferable to carry out in the range of 40-150 degreeC.

  Examples of the method for producing a film containing a fumaric acid diester resin in the present invention include forming the fumaric acid diester resin into a film by a solution casting method or a melt casting method. The solution casting method is a method in which a solution obtained by dissolving a fumaric acid diester resin in a solvent such as tetrahydrofuran (hereinafter referred to as a dope) is cast on a support substrate, and then the solvent is removed by heating or the like to obtain a film. is there. The melt casting method is a molding method in which a fumaric acid diester resin is melted in an extruder and extruded from a T-die slit into a film shape, and then cooled and cooled with a roll or air.

  The thickness of the film containing the fumaric acid diester resin in the present invention is preferably 30 to 200 μm, and more preferably 50 to 150 μm, in order to improve the workability of the film.

  The hard coat layer in the present invention contains inorganic particles and an organic component. The transparent conductive film obtained by the organic component alone is deformed and cracks occur when flattened. Moreover, it is difficult to form a film only with inorganic particles.

  Examples of the inorganic particles in the present invention include silica-based particles such as colloidal silica fine particles, carbonates such as calcium carbonate, and metal oxide-based particles such as titanium oxide. Silica-based particles are preferred, and colloidal silica fine particles are more preferred because control of the particle diameter is particularly easy. In order to improve the total light transmittance, the average particle diameter of the inorganic particles is preferably 400 nm or less, more preferably 100 nm or less, and particularly preferably 50 nm or less.

  The colloidal silica fine particles preferably used as the inorganic particles are those in which ultrafine particles of silicic acid anhydride having an average particle size in the range of 1 to 400 nm are dispersed in water or an organic solvent. Such colloidal silica fine particles can be produced by a known method, but are also commercially available.

  Here, the inorganic particles are preferably surface-treated with a polymerizable unsaturated group in terms of dispersibility and strength in a transparent film, and examples of the polymerizable unsaturated group include a (meth) acryloyl group. , A styryl group, a vinyl group, and the like. A (meth) acryloyl group is preferable because it is particularly highly reactive and excellent in productivity.

  The surface treatment method of the inorganic particles is not particularly limited, and in particular, the surface treatment method using an organic silane compound having a polymerizable unsaturated group is preferable. Examples of the surface treatment method include inorganic particles and a polymerizable unsaturated group. After the organic silane compound is mixed, a hydrolysis catalyst is added and the mixture is stirred at room temperature or under heating. Here, the hydrolysis reaction is carried out while azeotropically distilling water generated by the reaction with the dispersion catalyst in the inorganic particles at normal pressure or reduced pressure. At this time, a catalyst such as water, acid, base, salt or the like may be used for the purpose of promoting the reaction. In this way, surface-modified inorganic particles can be obtained.

  The organic silane compound having a polymerizable unsaturated group used in the surface treatment method is not particularly limited. For example, styryltrimethoxysilane, styryltriethoxysilane, vinyltris (3-methoxyethoxy) silane, vinyltriethoxysilane, vinyl Trimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycid Xylpropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane N-β (aminoethyl) -aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane etc. are mentioned. These can be used alone or in combination of two or more. Moreover, the silane compound which added (meth) acrylic acid to the epoxy group of these compounds and the glycidyl group, the silane compound which added the compound which has two (meth) acryloyloxy groups to an amino group, an amino group, and a mercapto group A silane compound in which a compound having a (meth) acryloyloxy group and an isocyanate group is added, a silane compound in which a compound having a (meth) acryloyloxy group and a hydroxyl group is added to an isocyanate group, or the like can also be used. Among these, from 3-methacryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-acryloyloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane The selected silane compound is preferable in terms of excellent reactivity.

  Examples of the organic component include an organic compound having a polymerizable group. Examples of the organic compound having a polymerizable group include an organic compound having a (meth) acryloyl group, an organic compound having a styryl group, and a vinyl group. An organic compound having a radically polymerizable group such as an organic compound having an ionic group; an organic compound having an ionic polymerizable group such as an organic compound having an epoxy group or an organic compound having an oxetane group. Among these, an organic compound having a radical polymerizable group is preferable from the viewpoint of high reactivity and the thermal stability of the resulting cured product, and an organic compound having a (meth) acryloyl group is more preferable from the viewpoint of productivity. Here, examples of the organic compound include urethane, epoxy, polyester, (meth) acrylate, and the like.

  Specific examples of the organic compound having a (meth) acryloyl group include urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, mono (meth) acrylate, di (meth) acrylate, mono and di Examples thereof include monofunctional or polyfunctional (meth) acrylic acid esters such as (meth) acrylamide.

  Specific examples of the urethane (meth) acrylate include 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1,4-diisocyanatopentane, 1,6-diisocyanato-3,5,5. -Trimethylhexane, 1,6-diisocyanato-3,3,5-trimethylhexane, 1,12-diisocyanatododecane, 1,8-diisocyanato-4-isocyanatomethyloctane, 1,3,6-triisocyanato Hexane, 1,6,11-triisocyanatoundecane, hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, 1,2-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,2-hydrogenated xylylene diisocyanate, 1,4-hydrogenated xylylene diisocyanate Isocyanate compounds such as tetramethylxylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, norbornane diisocyanate, decalin diisocyanate, lysine diisocyanate, lysine triisocyanate; polyethylene glycol (number of repeating units: 6 to 20), polypropylene glycol ( Number of repeating units: 6 to 20), polybutylene glycol (number of repeating units: 6 to 20), 1-methylbutylene glycol (number of repeating units: 6 to 20), polytetramethylene glycol (number of repeating units: 6 to 20), Polycaprolactone diol, caprolactone addition of alkylene (carbon number: 2 to 10) diol (repeat unit number: 2 to 10) diol, bisphenol A diol compound such as an ethylene oxide adduct of diol A, a propylene oxide adduct of bisphenol A, a polyester diol derived from phthalic acid and an alkylene diol, a polycarbonate diol (aliphatic skeleton having 4 to 6 carbon atoms); and 2-hydroxy Reaction of hydroxyl (meth) acrylates such as ethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1,4-diisocyanatopentane, 1,6-diisocyanato-3,5,5-trimethyl Hexane, 1,6-diisocyanato-3,3,5-trimethylhexane, 1,12-diisocyanatododecane, 1,8-diisocyanato-4-isocyanatomethyloctane, 1,3,6-triisocyanatohexane, 1,6,11-triisocyanatoundecane, hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, 1,2-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,2-hydrogenated xylylene diisocyanate, 1, 4-hydrogenated xylylene diisocyanate, tetramethylxylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, norbornane diisocyanate, decalin diisocyanate Monomers of isocyanate compounds such as lysine diisocyanate and lysine triisocyanate, and multimers thereof; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, The urethane (meth) acrylate etc. which added the (meth) acrylate which has hydroxyl groups, such as those caprolactone adducts, etc. are mentioned.

  Specific examples of the epoxy (meth) acrylate include, for example, (meth) acrylic acid or derivatives thereof to glycidyl ether compounds such as phenol novolac type epoxy resins, cresol novolac type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, and the like. And epoxy (meth) acrylate obtained by reacting with. Furthermore, for the purpose of adjusting the mechanical properties of the cured product to be produced, a compound having 1 to 2 radically polymerizable ethylenically unsaturated bonds in the molecule may be appropriately contained as necessary. Examples of the compound having an ethylenically unsaturated bond capable of radical polymerization include ester type mono- or di (meth) acrylates derived from various alkyl mono- or polyalcohols; mono- or di (meth) acrylamides Vinyl ether compounds, vinyl ester compounds, other vinyl compounds, and allyl compounds.

  Specific examples of the polyester (meth) acrylate include, for example, polybasic acids such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, and adipic acid; ethylene glycol, propylene glycol, neopentyl glycol, caprolactan diol, 1 Polyhydric alcohols such as 1,6-hexanediol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and bisphenol A; polyester (meth) acrylate obtained by reaction with (meth) acrylic acid or a derivative thereof.

  Specific examples of mono (meth) acrylate include, for example, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, (meth ) I-butyl acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylic Tetrahydrofurfuryl acid, morpholyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 4-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxy (meth) acrylate Butyl, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate Diethylaminoethyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate, dicyclopentenyl (meth) acrylate, (meta ) Allyl acrylate, 2-ethoxyethyl (meth) acrylate, isobornyl (meth) acrylate, phenyl (meth) acrylate, and the like.

  Specific examples of di (meth) acrylate include, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, Polyethylene glycol di (meth) acrylate (number of repeating units: 5 to 14), propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, di (meth) ) Tetrapropylene glycol acrylate, polypropylene glycol di (meth) acrylate (number of repeating units: 5 to 14), 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate , Poly (butylene) di (meth) acrylate Recall (repeating unit number: 3 to 16), poly (1-methylbutylene glycol) di (meth) acrylate (repeating unit number: 5 to 20), 1,6-hexanediol di (meth) acrylate, di ( 1,9-nonanediol of (meth) acrylic acid, neopentyl glycol di (meth) acrylate, neopentyl glycol hydroxypivalate di (meth) acrylate, di (meth) acrylate of dicyclopentanediol, hydroxypivalic acid Di (meth) acrylic acid ester of caprolactone adduct of neopentyl glycol, di (meth) acrylic acid ester of γ-butyrolactone adduct of neopentyl glycol hydroxypivalate, di (meth) acrylic of caprolactone adduct of neopentyl glycol Acid ester, butylene glycol Di (meth) acrylic acid ester of caprolactone adduct, di (meth) acrylic acid ester of caprolactone adduct of cyclohexanedimethanol, di (meth) acrylic acid ester of caprolactone adduct of dicyclopentanediol, bisphenol A Di (meth) acrylic acid ester of caprolactone adduct, di (meth) acrylic acid ester of caprolactone adduct of bisphenol F, dimethylol tricyclodecane di (meth) acrylic acid ester, neopentyl glycol modified trimethylolpropane di (meth) ) Acrylic acid ester, di (meth) acrylic acid ester of bisphenol A ethylene oxide adduct, di (meth) acrylic acid ester of bisphenol A propylene oxide adduct, bisphenol F ethylene oxide Di de adduct (meth) acrylic acid ester, di (meth) acrylate of bisphenol F propylene oxide adduct.

  Specific examples of mono- and di (meth) acrylamides include (meth) acrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N-methylol (meth) acrylamide, N-methoxymethyl ( Examples include meth) acrylamide, N-butoxymethyl (meth) acrylamide, Nt-butyl (meth) acrylamide, (meth) acryloylmorpholine, and methylenebis (meth) acrylamide.

  Specific examples of the polyfunctional (meth) acrylic acid esters include dipentaerythritol hexaacrylate, trimethylolpropane triacrylate, and the like.

  Among these, as the organic component, (meth) acrylate having a (meth) acryloyl group is preferable.

  These can be used individually by 1 type or in combination of 2 or more types.

  The ratio of the inorganic particles and the organic component in the hard coat layer is preferably 1 to 95% by weight of the inorganic particles and 99 to 5% by weight of the organic components, more preferably 10 to 80% by weight of the inorganic particles, from the viewpoint of the coatability of the hard coat. The organic component is 90 to 20% by weight, particularly preferably 40 to 70% by weight of the inorganic particles and 60 to 30% by weight of the organic component.

  The hard coat layer is obtained by curing a composition containing inorganic particles and an organic component. As a method for producing the hard coat layer, for example, a composition containing inorganic particles and an organic component is used. Examples thereof include a hard coat layer formed by radical polymerization by irradiation with active energy rays and / or heating.

  In radical polymerization, it is preferable to use a polymerization initiator. Examples of the polymerization initiator include benzophenone, 4,4-bis (diethylamino) benzophenone, 2,4,6-trimethylbenzophene, and methyl orthobenzoyl. Benzoate, 4-phenylbenzophenone, thioxanthone, diethylthioxanthone, isopropylthioxanthone, chlorothioxanthone, t-butylanthraquinone, 2-ethylanthraquinone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1 Photopolymerization initiators such as -one, methylbenzoylformate, 1-hydroxycyclohexyl phenylketone; methyl ethyl ketone peroxide, benzoyl peroxide, dicumyl peroxide, t-butyl hydroperoxide Oxide, cumene hydroperoxide, t- butyl peroxy octoate, t- butyl peroxybenzoate, thermal polymerization initiator such as lauroyl peroxide. These polymerization initiators are selected in consideration of production processing surfaces such as productivity and storage stability, and quality aspects such as coloring, and photopolymerization initiators are preferably used because they are particularly excellent in productivity.

  Moreover, as a kind of active energy ray, well-known active energy rays, such as an electron beam, an ultraviolet-ray, infrared rays, and visible light, are mentioned, for example. Among them, it is preferable to use ultraviolet rays because of its high versatility and excellent device cost and productivity. As the light source for generating the ultraviolet rays, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a medium pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a high frequency induction mercury lamp, and the like are suitable.

  The atmosphere at the time of curing by irradiation with active energy rays may be an atmosphere of an inert gas such as nitrogen or argon, or an air atmosphere. Among these, since it is simple and low-cost, it is preferable to be in an air atmosphere.

The curing conditions are not particularly limited. For example, when active energy rays are used, the irradiation dose is preferably set to a value within the range of 0.01 to 10 J / cm ² in order to complete the curing reaction. , even more preferably within a range of 0.1~5J / cm ^2, particularly preferably to a value within the range of 0.3~3J / cm ^2. Moreover, when making it harden | cure by heating, in order to complete hardening reaction, it is preferable to heat for 1 to 180 minutes at the temperature within the range of 30-200 degreeC, and it is 2- It is more preferable to heat for 120 minutes, and it is particularly preferable to heat at a temperature in the range of 80 to 150 ° C. for 5 to 60 minutes.

  A commercially available hard coat agent can also be used as the hard coat layer of the present invention. Examples of commercially available hard coat agents containing inorganic particles include JSR hard coat agent Desolite, Mitsubishi Rayon hard coat agent Ray Queen, Arakawa Chemical Industries hard coat agent comporacene, Adeka Co., Ltd. hard coat agent Adeka Nano Hybrid Silicone FX-V etc. are mentioned.

  The thickness of the hard coat layer is preferably 1 to 20 μm and more preferably 5 to 15 μm for improving productivity.

  As a method for producing a film substrate including a fumaric acid diester resin provided with a hard coat layer containing inorganic particles and an organic component on both sides of the transparent conductive film of the present invention, for example, a film containing a fumaric acid diester resin A film substrate containing a fumaric acid diester resin is produced by applying a composition to form a hard coat layer to form a coating film, followed by radical polymerization by irradiation with active energy rays and / or heating. Is mentioned.

  When applying, it is preferable to use an organic solvent from the viewpoints of viscosity adjustment, dispersion stability, adhesion to the base material, and smoothness and uniformity of the hard coat layer. When using the organic solvent, in order to complete the curing reaction, it is preferable to volatilize the solvent after coating and before curing. The method is not particularly limited, and the hard coat layer can be formed using known means such as infrared drying or drying in a hot air oven in addition to natural drying.

  The thickness of the film substrate containing a fumaric acid diester resin provided with a hard coat layer containing inorganic particles and an organic component in the present invention is preferably 30 to 200 μm, more preferably 40 to 150 μm, in order to improve productivity. It is a range. In order to improve visibility as a display element, the total light transmittance is preferably 85% or more, and more preferably 90% or more.

  The film substrate in the present invention may contain an antioxidant or a light stabilizer for the purpose of improving thermal stability or light stability. Examples of the antioxidant include hindered phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, lactone-based antioxidants, amine-based antioxidants, hydroxyl-based antioxidants, and vitamin E-based agents. Antioxidants and other antioxidants can be mentioned. Examples of the light stabilizer include hindered amine light stabilizers. These antioxidants or light stabilizers may be used alone or in combination.

  Moreover, the film substrate in the present invention may contain an ultraviolet absorber for the purpose of preventing deterioration of the display element. As the ultraviolet absorber, for example, an ultraviolet absorber such as benzotriazole, benzophenone, triazine, or benzoate can be added as necessary. One or more of these ultraviolet absorbers can be used in combination.

  Furthermore, the film substrate in the present invention is blended with other polymers, surfactants, polymer electrolytes, conductive complexes, pigments, dyes, antistatic agents, antiblocking agents, lubricants and the like within the scope of the invention. It may be.

  The transparent conductive film in the present invention contains a metal oxide (ITO), and the thickness of the transparent conductive film is preferably 100 to 300 nm, and more preferably 200 to 300 nm.

  The ratio of indium oxide and tin oxide in the metal oxide (ITO) composed of a mixture of indium oxide and tin oxide is preferably 80% by weight or more of indium oxide and 20% by weight or less of tin oxide in order to improve resistivity. More preferably, 90 to 95% by weight of indium and 5 to 10% by weight of tin oxide are used.

  Generally, the manufacturing method of a transparent conductive film forms a transparent conductive film on a film substrate by sputtering. In this manufacturing method, when the film substrate used is softer and has a larger thermal expansion than glass, particularly on one side of the film substrate, the film thickness is 200 nm or more and the ITO crystallizes at 150 ° C. or higher. When the film is formed at a temperature of 1, a problem arises that warpage occurs.

  On the other hand, in general, in a method for producing a transparent conductive film, it is necessary to heat ITO at a temperature of 150 ° C. or higher to crystallize ITO in the transparent conductive film, thereby reducing the resistance to the display element. It is required to suppress warping of the transparent conductive film that occurs.

In the method for producing a transparent conductive film of the present invention, when a transparent conductive film is formed on a film substrate by sputtering, the ITO becomes an amorphous structure by forming the ITO near room temperature, and a transparent conductive film without warping is formed. It is made. However, when the transparent conductive film is formed at this temperature, the resistivity is 5 × 10 ⁻⁴ Ω · cm, and the resistivity is high for application as a display element. Therefore, in order to obtain a transparent conductive film having a resistivity suitable for a display element, the present invention reduces the resistivity by forming a transparent conductive film on a film substrate and then heating at 200 ° C. or more to crystallize ITO. Is.

  Here, the present invention provides a method for producing a transparent conductive film by forming a transparent conductive film containing ITO by sputtering in order to reduce resistivity and suppress warping by crystallizing ITO. After forming a transparent conductive film having a crystal structure, it is preferable to transition the amorphous conductive film to a crystal structure by heating the transparent conductive film at a temperature of 200 to 250 ° C.

  And this invention is 200 degreeC or more because the film board | substrate in which a transparent conductive film is formed is a film board | substrate containing the fumaric acid diester type resin in which the hard-coat layer containing an inorganic particle and an organic component was provided in both sides. Even when heated at a temperature of 1, it is possible to suppress warping when ITO is transferred to a crystal structure, and it is possible to produce a transparent conductive film with small warping.

  In the case where a transparent conductive film is formed on a plastic substrate in the present invention to obtain a transparent conductive film, the warp as the transparent conductive film should be 1 mm or less in order to make it more suitable for use as a display element. preferable.

  In the transparent conductive film of this invention, since it becomes a film excellent in transparency and moisture permeability, it is preferable that the transparent barrier film is provided between the film substrate and the transparent conductive film.

  Examples of the transparent barrier film include an inorganic film and an organic film. Examples of the inorganic film include metal oxides such as silicon oxide, aluminum oxide, and tantalum oxide; silicon nitride, aluminum nitride, tantalum nitride, and the like. Metal nitrides: Examples include films containing metal nitride oxides such as silicon nitride oxide, aluminum nitride oxide, and tantalum nitride oxide, and aluminum films. Examples of the organic film include films made of polyvinyl alcohol, polyolefin, and the like. It is done. Among these, an inorganic film excellent in transparency is preferable, and a film containing metal oxide, metal nitride, or metal nitride oxide is more preferable.

  In the case of an inorganic film, the thickness of the transparent barrier film is preferably from 1 to 1000 nm, more preferably from 10 to 300 nm, in order to improve the water vapor barrier property. 100 micrometers is preferable and 1-50 micrometers is further more preferable. These transparent barrier films can be formed by laminating and multilayering an organic film and an inorganic film. The transparent barrier film can be formed by a known method such as vapor deposition, sputtering, PECVD, CatCVD, coating or laminating.

The moisture permeability of the transparent conductive film of the present invention is preferably 1 g / m ² / day or less in order to protect the display element.

The transparent conductive film of the present invention has a resistivity of 2 × 10 ⁻⁴ Ω · cm or less and a total light transmission in order to ensure the resistivity as a display element electrode and the visibility necessary for display. The rate is 80% or more.

  Since the transparent conductive film of the present invention has sufficient resistivity and visibility necessary for display, the transparent plastic substrate for liquid crystal display elements, the transparent plastic substrate for organic EL display elements, and the transparent plastic for electrophoretic display elements It can be preferably used for a substrate, a transparent plastic substrate for electrostatic force driven display elements, and the like.

  ADVANTAGE OF THE INVENTION According to this invention, the transparent conductive film useful as an object for display elements, especially a transparent conductive film with a small curvature and excellent in electroconductivity and transparency can be provided.

  EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

<Composition of fumaric acid diester resin>
Using a nuclear magnetic resonance measuring apparatus (manufactured by JEOL, trade name JNM-GX270), it was determined by proton nuclear magnetic resonance spectroscopy ( ¹ H-NMR) spectrum analysis.

<Measurement of number average molecular weight>
Using gel permeation chromatography (GPC) (manufactured by Tosoh Corporation, trade name HLC-802A), THF was used as a solvent and a standard polystyrene conversion value was obtained.

<Transparency evaluation method>
The total light transmittance and haze were measured according to JIS K 7361-1 using a haze meter (trade name NDH2000, manufactured by Nippon Denshoku Industries Co., Ltd.).

<Measurement of moisture permeability>
Moisture permeability test method (cup method) Measured according to JIS Z 0208.

<Measurement of resistivity>
The resistivity was measured by the van der Pau method.

<Adhesion evaluation method>
After repeating heat treatment at 200 ° C. for 1 hour 5 times, 100 mm grids (10 × 10) of 1 mm are made on the effective surface by the method according to JIS K 5600-5-6, and using the cellophane adhesive tape, the effective surface It peeled after making it adhere | attach. Judgment is represented by the number of squares that are not peeled out of 100 grids. The case where 100 squares are not peeled is represented by ◯, and the case where 10 squares or more are peeled is represented by x.

<Evaluation method of warpage>
A 100 mm square film was placed on a plane, the height from the plane was measured at four corners of the film, and the maximum height was expressed as a warp.

Synthesis Example 1 (Production Example of Fumaric Acid Diester Resin)
In a 500 mL four-necked flask equipped with a stirrer, a condenser tube, a nitrogen inlet tube and a thermometer, 0.4 g of polyvinyl alcohol (molecular weight 2,000, saponification degree 80%), 260 g of distilled water, 137.5 g of diisopropyl fumarate (0 .687 mol), 2.5 g (0.015 mol) of methyl-3-ethyl-3-oxetanyl acrylate and 0.8 g (0.005 mol) of t-butylperoxypivalate as a polymerization initiator, After carrying out nitrogen bubbling for 1 hour, radical copolymerization was carried out by maintaining at 50 ° C. for 24 hours while stirring at 550 rpm. After completion of the copolymerization reaction, the polymer in the flask was filtered off and washed with distilled water and methanol to obtain a fumaric acid diester resin (yield: 82%). ^{According to 1} H-NMR measurement, the obtained fumaric acid diester resin was diisopropyl fumarate residue unit / acrylic acid-3-ethyl-3-oxetanylmethyl residue unit = 96/4 (mol%). The number average molecular weight of the fumaric acid diester resin was 47,000.

Synthesis example 2 (film production example)
The fumaric acid diester resin obtained in Synthesis Example 1 was dissolved in a 1: 1 solution of toluene: methyl ethyl ketone to give a 20 wt% solution, and tris (2,4- Di-t-butylphenyl) phosphite 1.0 part by weight and pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] 0.5 part by weight were added and supported. It was cast on a body substrate, dried at 70 ° C. for 10 minutes, and further dried at 120 ° C. for 10 minutes. A roll film having a thickness of 120 μm and a thickness unevenness of 3 μm was produced.

Synthesis example 3 (hard coat solution preparation example 1)
Into a 5-liter four-necked flask equipped with a stirrer, a thermometer and a condenser, isopropanol silica sol (colloidal silica fine particle SiO2 concentration: 30% by weight, average particle size: 20 nm, manufactured by Nissan Chemical Industries, Ltd.) 2, 000 parts by weight and 160 parts by weight of 3-methacryloyloxypropyltrimethoxysilane having a methacryloyl group as a polymerizable group (manufactured by Toshiba Silicon Co., Ltd.) are weighed and heated while being stirred. At the same time as starting, 100 parts by weight of pure water was gradually added dropwise, and after completion of the addition, hydrolysis was carried out with stirring for 2 hours under reflux. After the reaction, 500 parts by weight of toluene was added, and alcohol, water and the like were azeotropically distilled together with toluene. Next, 1,000 parts by weight of toluene was added, and the reaction was performed at 110 ° C. for 4 hours while distilling toluene. The obtained dispersion had a solid concentration of 65% by weight and a viscosity of 55 cps. 100 parts by weight (solid content: 65% by weight) of the dispersion obtained as inorganic particles, 23.3 parts by weight of dipentaerythritol hexaacrylate (trade name: Kayrad DPHA, Nippon Kayaku Co., Ltd.) as the organic component, 20 parts by weight of trimethylolpropane triacrylate (manufactured by Osaka Organic Chemical Co., Ltd.) and 1 part by weight of a photopolymerization initiator (trade name; Darocur 1173 manufactured by Ciba Specialty Chemicals Co., Ltd.) were mixed and stirred to obtain a composition (inorganic 60% by weight of particles and 40% by weight of organic components). 100 parts by weight of methyl ethyl ketone was added to the obtained composition to obtain a hard coat solution.

Synthesis example 4 (hard coat solution preparation example 2)
Dipentaerythritol hexaacrylate (trade name: Kayrad DPHA, Nippon Kayaku Co., Ltd.) 50 parts by weight, trimethylolpropane triacrylate (Osaka Organics Co., Ltd.) 35 parts by weight, isobornyl acrylate (Osaka Organics Co., Ltd.) 10 parts by weight), 5 parts by weight of 4-hydroxyethyl acrylate, photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd., trade name; Darocur 1173), 1 part by weight of antioxidant (Ciba Specialty Chemicals) Co., Ltd. product name: Irganox 1010) 1.4 parts by weight were mixed and stirred to obtain a composition (inorganic particles 0% by weight, organic component 100% by weight). 100 parts by weight of methyl ethyl ketone was added to the obtained composition to obtain a hard coat solution.

Example 1
Using the roll film prepared in Synthesis Example 2, the hard coat solution prepared in Synthesis Example 3 was applied with a coater to form a coating film, dried at 60 ° C. for 2 minutes, and then irradiated with ultraviolet light with a high-pressure mercury lamp (irradiation the amount 300 mJ / cm ^2), the film comprising a fumaric diester resin, a hard coat layer having a thickness of 10μm was obtained a film substrate which is provided by curing. Similarly, a 10 μm hard coat layer was formed on the back surface of the film substrate to obtain a film substrate.

  The obtained film substrate had a total light transmittance of 92% and a haze of 0.7%.

  Using the obtained film substrate, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three targets having a diameter of 8 inches.

A Si target was used as a target for forming the transparent barrier film, and argon and O ₂ were used as the sputtering gas. A 100 nm-thick transparent barrier film containing silicon oxide is formed under conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 80%, O ₂ 20%) and RF power 500 W. Formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 200 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 80%, a moisture permeability of 0.6 g / m ² / day, a resistivity of 2 × 10 ⁻⁴ Ω · cm, and a warpage of 0.5 mm. Moreover, in evaluation of adhesiveness, it was excellent in (circle) and the adhesiveness after repeated heat processing.

Example 2
Using the film substrate obtained in Example 1, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

A Si target was used as a target for forming the transparent barrier film, and argon and N ₂ were used as the sputtering gas. A 100 nm thick transparent barrier film containing silicon nitride is formed under conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 80%, N ₂ 20%) and RF power 500 W. Formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating and contains 300 nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 200 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 80%, a moisture permeability of 0.4 g / m ² / day, a resistivity of 1.5 × 10 ⁻⁴ Ω · cm, and a warpage of 1 mm. Moreover, in evaluation of adhesiveness, it was excellent in (circle) and the adhesiveness after repeated heat processing.

Example 3
Using the film substrate obtained in Example 1, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

A Si target was used as a target for forming the transparent barrier film, and argon and N ₂ were used as the sputtering gas. Film formation was performed under conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 80%, N ₂ 20%) and RF power 500 W, and a 50 nm thick transparent barrier film containing silicon nitride was formed. Formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 200 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 80%, a moisture permeability of 0.6 g / m ² / day, a resistivity of 2 × 10 ⁻⁴ Ω · cm, and a warpage of 0.5 mm. Moreover, in evaluation of adhesiveness, it was excellent in (circle) and the adhesiveness after repeated heat processing.

Example 4
Using the film substrate obtained in Example 1, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

A SiO ₂ target was used as a target for forming the transparent barrier film, and argon and N ₂ were used as the sputtering gas. A transparent barrier film having a thickness of 50 nm and containing silicon nitride oxide is formed under the conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, N ₂ 5%) and RF power 500 W. Was formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 200 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 82%, a moisture permeability of 0.9 g / m ² / day, a resistivity of 2 × 10 ⁻⁴ Ω · cm, and a warpage of 0.5 mm. Moreover, in evaluation of adhesiveness, it was excellent in (circle) and the adhesiveness after repeated heat processing.

Example 5
Using the film substrate obtained in Example 1, a transparent conductive film was formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 200 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 84%, a moisture permeability of 20 g / m ² / day, a resistivity of 2 × 10 ⁻⁴ Ω · cm, and a warpage of 0.8 mm. Moreover, in evaluation of adhesiveness, it was excellent in (circle) and the adhesiveness after repeated heat processing. Since the barrier film was not formed, the moisture permeability was large, but the total light transmittance was high, the resistivity was low, and the warp was small, so as a transparent conductive film for display elements It had excellent performance.

Example 6
Using the film substrate obtained in Example 1, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

A Si target was used as a target for forming the transparent barrier film, and argon and O ₂ were used as the sputtering gas. A 100 nm-thick transparent barrier film containing silicon oxide is formed under conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 80%, O ₂ 20%) and RF power 500 W. Formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 5 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 200 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 85%, a moisture permeability of 0.9 g / m ² / day, a resistivity of 2 × 10 ⁻⁴ Ω · cm, and a warpage of 0.5 mm. Moreover, in evaluation of adhesiveness, it was excellent in (circle) and the adhesiveness after repeated heat processing.

Example 7
Using the film substrate obtained in Example 1, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

A Si target was used as a target for forming the transparent barrier film, and argon and O ₂ were used as the sputtering gas. A 100 nm-thick transparent barrier film containing silicon oxide is formed under conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 80%, O ₂ 20%) and RF power 500 W. Formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 250 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 81%, a moisture permeability of 0.9 g / m ² / day, a resistivity of 1.6 × 10 ⁻⁴ Ω · cm, and a warpage of 0.9 mm. . Moreover, in evaluation of adhesiveness, it was excellent in the adhesiveness after (circle) and repeated heat processing Comparative Example 1
Using the film substrate obtained in Example 1, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

A Si target was used as a target for forming the transparent barrier film, and argon and O ₂ were used as the sputtering gas. A 100 nm-thick transparent barrier film containing silicon oxide is formed under conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 80%, O ₂ 20%) and RF power 500 W. Formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate was formed at a heating temperature of 200 ° C., and 200 nm thick ITO A transparent conductive film having a crystalline structure containing was obtained.

The obtained transparent conductive film had a total light transmittance of 78%, a moisture permeability of 0.6 g / m ² / day, a resistivity of 1.9 × 10 ⁻⁴ Ω · cm, and a warp of 30 mm. It was. Warping was increased by forming the transparent conductive film by heating the transparent film substrate.

Comparative Example 2
Using the roll film produced in Synthesis Example 2, the hard coat solution produced in Synthesis Example 4 was applied with a coater to form a coating film, dried at 60 ° C. for 2 minutes, and then irradiated with ultraviolet light with a high-pressure mercury lamp (irradiation) The film board | substrate with which the hard-coat layer of thickness 10 micrometers formed by hardening to the film containing quantity 300mJ / cm < ² >) bridge | crosslinking fumaric acid diester type resin was obtained. Similarly, a 10 μm hard coat layer was formed on the back surface of the film substrate to obtain a film substrate.

  The obtained film substrate had a total light transmittance of 91% and a haze of 0.8%.

Using the obtained film substrate, a magnetron sputtering apparatus equipped with three 8 inch diameter targets, and using an ITO target containing 10 wt% SnO ₂ as a target for forming a transparent conductive film as follows, As the gas, argon and O ₂ were used. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 200 ° C. to obtain a transparent conductive film having a crystalline structure.

  The obtained transparent conductive film was greatly deformed and warpage was 22 mm. Since a hard coat layer containing 100% of an organic component was used as the hard coat layer, warping was increased.

Comparative Example 3
Using the film substrate obtained in Example 1, a transparent barrier film and a transparent conductive film were formed on the film substrate as follows using a magnetron sputtering apparatus provided with three 8 inch diameter targets.

A Si target was used as a target for forming the transparent barrier film, and argon and O ₂ were used as the sputtering gas. A 100 nm-thick transparent barrier film containing silicon oxide is formed under conditions of ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 80%, O ₂ 20%) and RF power 500 W. Formed on a film substrate.

Further, a transparent conductive film was formed on the transparent barrier film as follows. An ITO target containing 10 wt% SnO ₂ was used as a target for forming the transparent conductive film, and argon and O ₂ were used as the sputtering gas. Ultimate vacuum 5 × 10 ⁻⁵ Pa, sputtering gas pressure 0.5 Pa (argon gas 95%, O ₂ 5%), DC power 300 W, transparent film substrate is formed without heating, and contains 200-nm thick ITO A transparent conductive film having an amorphous structure was obtained. Thereafter, the transparent conductive film having an amorphous structure was heated at 180 ° C. to obtain a transparent conductive film having a crystalline structure.

The obtained transparent conductive film had a total light transmittance of 82%, a moisture permeability of 0.9 g / m ² / day, a resistivity of 2.2 × 10 ⁻⁴ Ω · cm, and a warpage of 0.9 mm. . Moreover, in evaluation of adhesiveness, it was excellent in (circle) and the adhesiveness after repeated heat processing.

Claims (9)

A transparent conductive film in which a transparent conductive film containing ITO formed by sputtering is provided on one side of a film substrate containing a fumaric acid diester resin provided with a hard coat layer containing inorganic particles and an organic component on both sides A transparent conductive film having a resistivity of 2 × 10 ⁻⁴ Ω · cm or less and a total light transmittance of 80% or more. On one side of a film substrate containing a fumaric acid diester resin provided with a hard coat layer containing inorganic particles and an organic component on both sides, a transparent conductive film containing ITO is formed at about room temperature by sputtering, and is 200 to 250 ° C. The transparent conductive film according to claim 1, wherein the transparent conductive film is obtained by heating. The transparent conductive film according to claim 1 or 2, wherein the warp of the transparent conductive film is 1 mm or less. The transparent conductive film according to any one of claims 1 to 3, wherein the fumaric acid diester resin contains 50 mol% or more of a fumaric acid diester residue unit represented by the following general formula (1).

(Here, R ₁ and R ₂ each independently represents a branched or cyclic alkyl group having 3 to 12 carbon atoms.) The film thickness of a transparent conductive film is 100-300 nm, The transparent conductive film in any one of Claims 1-4 characterized by the above-mentioned. The transparent conductive film according to any one of claims 1 to 5, wherein a transparent barrier film is provided between the film substrate and the transparent conductive film. The transparent conductive film according to claim 6, wherein the transparent barrier film is selected from the group consisting of a metal oxide, a metal nitride, and a metal nitride oxide, and has a moisture permeability of 1 g / m ² / day or less. Sex film. In a method for producing a transparent conductive film by forming a transparent conductive film containing ITO by sputtering, a transparent conductive film having an amorphous structure is formed by sputtering with ITO, and then the transparent conductive film is heated at a temperature of 200 to 250 ° C. A process for producing a transparent conductive film, wherein the amorphous structure is transformed to a crystal structure. A transparent plastic substrate for a liquid crystal display element, a transparent plastic substrate for an organic EL display element, a transparent plastic substrate for an electrophoretic display element, comprising the transparent conductive film according to claim 1, or Transparent plastic substrate for electrostatic force driven display elements.