JPH1134206A - Transparent conductive film and touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability against pen input in using as a touch panel by providing film containing a transparent plastic film layer, a cushioning layer having specified value of dynamic hardness formed on one side of the film layer, and a transparent conductive thin film layer formed on the cushioning layer. SOLUTION: Transparent conductive film 101 is composed of a plastic film layer 11, a cushioning layer 12 formed on one side of the plastic film layer 11, and a transparent conductive thin film layer 14 formed on the cushioning layer 12. The cushioning layer 12 is for relieving pen input impact, when the transparent conductive film 101 is used for a touch panel. The hardness thereof should be 0.005-2 dynamic hardness. If the dynamic hardness is less than 0.005, the film is too soft for forming the transparent conductive thin film 14 on the cushioning layer 12. Meanwhile, if the dynamic hardness is more than 2, cushioning effect against pen input is not developed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent conductive film using a plastic film and a touch panel using the same. In particular, the present invention relates to a transparent conductive film capable of providing a touch panel excellent in pen input resistance.

[0002]

2. Description of the Related Art A transparent conductive film in which a thin film of a transparent and conductive compound is formed on a transparent plastic film is used in applications utilizing the conductivity, for example, the transparency of flat panel displays such as liquid crystal displays and EL displays and touch panels. Widely used in electrical and electronic fields such as electrodes.

[0003] As a compound constituting a transparent conductive thin film, generally, tin oxide, indium oxide, indium oxide / tin oxide, zinc oxide and the like are typical, and as a substrate thereof, polyethylene terephthalate or the like is used. Various plastic films are used.

[0004]

In recent years, with the spread of portable information terminals, conductive films have been required to have a function of inputting characters with a pen. Accordingly, it has been demanded that the durability of the film does not cause deterioration in conductivity due to pen input. However, when a transparent conductive film is used for a touch panel, a pair of conductive thin films opposed to each other via a spacer come into strong contact with each other by pressing with a pen input. There has been a problem that the resistance is increased or disconnection occurs.

In order to improve the durability against only a point load, that is, the hitting point characteristics, a transparent conductive thin film is formed on a transparent plastic film having a thickness of 120 μm or less, and is bonded to another transparent substrate with an adhesive layer. A transparent conductive film (JP-A-2-66809) has been proposed.
The durability against pen input is not sufficient.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve a pen input durability when a transparent conductive thin film is formed on a transparent plastic film and used in a touch panel. The purpose is.

[0007]

As a result of intensive studies to achieve the above object, the present inventors have found that one surface of a transparent plastic film has a dynamic hardness of 0.1.
By forming the transparent conductive thin film layer via the cushion layer in the range of 005 to 2 the transparent conductive film having excellent pen input durability when used for a touch panel was discovered. The invention has been completed.

That is, the present invention relates to (1) a transparent plastic film layer, which is formed on one surface of the film layer;
A transparent conductive film including a cushion layer having a dynamic hardness of 0.005 to 2 and a transparent conductive thin film layer formed on the cushion layer; (2) formed between the cushion layer and the transparent conductive thin film layer And (3) a hard coat treatment layer formed on the surface of the transparent plastic film layer opposite to the surface on which the transparent conductive thin film layer is formed. The transparent conductive film according to the above (1) or (2), comprising:
(4) The transparent conductive film according to (1) or (2), further including an antiglare treatment layer formed on a surface of the transparent plastic film layer opposite to a surface on which the transparent conductive thin film layer is formed, ( 5) The transparent conductive film according to the above (1) or (2), including an antireflection treatment layer formed on the surface of the transparent plastic film layer opposite to the surface on which the transparent conductive thin film layer is formed; 6) A touch panel in which a pair of panel plates each having a transparent conductive thin film layer is arranged via a spacer so that the transparent conductive thin film layers face each other, and at least one of the panel plates has any of the above (1) to (1). 5) A touch panel comprising the transparent conductive film according to any one of the above items.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The transparent plastic film layer forming the transparent conductive film of the present invention can be obtained by, if necessary, forming a film obtained by melt extrusion or solution extrusion of an organic polymer in the longitudinal direction and / or width. It is obtained by stretching in the direction, cooling and heat setting.

Examples of the organic polymer include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polyethylene-2,6-naphthalate, polyamides such as nylon 6, nylon 4, nylon 66 and nylon 12, polyimides and polyamides. Imide, polyether sulfane, polyether ether ketone, polycarbonate, polyarylate, polyacryl, cellulose propionate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyetherimide, polyphenylene sulfide, polyphenylene oxide, polystyrene, syndiotactic Tic polystyrene, norbornene-based polymers, and the like. Of these, polyethylene terephthalate, polyethylene-2,6-naphthalate, syndiotactic polystyrene and the like are most preferably used. In addition, these organic polymers may be copolymerized or blended with a small amount of another organic polymer.

The thickness of the transparent plastic film layer is 1
It is preferably in the range of more than 0 μm and 300 μm,
More preferably, it is 70 to 250 μm. When the thickness is more than 10 μm and in the range of 300 μm, the mechanical strength is sufficient, and the deformation due to pen input when used for a touch panel is small, and the durability is sufficient. There is no need to increase the load at the time of input.

The transparent plastic film layer may be subjected to a surface treatment such as a corona discharge treatment or a glow discharge treatment, or a known anchor coat treatment, as long as the object of the present invention is not impaired.

A cushion layer is laminated on one side of the transparent plastic film layer. This cushion layer is a layer provided to reduce the impact of pen input when the transparent conductive film is used for a touch panel, and must be soft. Due to the shock absorbing effect exhibited by this layer, cracks and peeling, increase in electric resistance and breakage of the transparent conductive thin film layer at the time of pen input are prevented. The hardness of the cushion layer is in the range of 0.005 to 2 in dynamic hardness, preferably 0.007 to 1.
8 is within the range. When the dynamic hardness is smaller than 0.005, the transparent conductive thin film cannot be formed on the layer because it is too soft. On the other hand, if the dynamic hardness is larger than 2, the cushion effect for pen input is not exhibited.

The dynamic hardness is a hardness calculated from a load P (mN) and a penetration length D (μm) of the indenter into the resin at the time when a triangular indenter is pressed against the resin surface. When the tip angle of the triangular cone indenter is 115 °, the dynamic hardness DH is defined by the following equation. DH = 3.8584 × P / D ^{2 In} order to measure the average hardness of the resin, the penetration length D (μm) into the resin was set to 0.5 μm in this specification.

The resin used to form the cushion layer includes polyester resin, polyamide resin, polyacryl resin, polyurethane resin, silicone resin and the like. These resins may be copolymerized or blended in small amounts with other resins.

Among these resins, polyester resins are obtained from polyhydric carboxylic acids and polyhydric alcohols.
Examples of the polycarboxylic acids include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, diphenic acid, sulfoterephthalic acid, 5-sulfoisophthalic acid,
-Sulfophthalic acid, 4-sulfonaphthalene-2,7 dicarboxylic acid, 5 [4-sulfophenoxy] isophthalic acid,
Aromatic dicarboxylic acids such as sulfoterephthalic acid, metal salts and ammonium salts thereof; p-oxybenzoic acid, p-
Aromatic hydroxycarboxylic acids such as (hydroxyethoxy) benzoic acid; aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid; fumaric acid, maleic acid, itaconic acid, hexahydrophthalic acid; Examples thereof include unsaturated aliphatic dicarboxylic acids such as tetrahydrophthalic acid and alicyclic dicarboxylic acids, and trivalent or higher polycarboxylic acids such as trimellitic acid, trimesic acid, and pyromellitic acid.

Examples of polyhydric alcohols include aliphatic polyhydric alcohols, alicyclic polyhydric alcohols, and aromatic polyhydric alcohols. As aliphatic polyhydric alcohols, ethylene glycol, propylene glycol,
1,3-propanediol, 2,3-butanediol,
1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, neopentyl glycol,
Diethylene glycol, dipropylene glycol, 2,
Aliphatic diols such as 2,4-trimethyl-1,3-pentanediol, polyethylene glycol, polypropylene glycol and polytetramethylene glycol; triols and tetraols such as trimethylolethane, trimethylolpropane, glycerin and pentaerythritol; Can be exemplified.

The alicyclic polyhydric alcohols include 1,4
-Cyclohexanediol, 1,4-cyclohexanedimethanol, spiroglycol, hydrogenated bisphenol A, ethylene oxide adduct and propylene oxide adduct of hydrogenated bisphenol A, tricyclodecanediol, tricyclodecanedimethanol, etc. Can be exemplified.

The aromatic polyhydric alcohols include para-xylene glycol, meta-xylene glycol, ortho-xylene glycol, 1,4-phenylene glycol,
Examples thereof include an ethylene oxide adduct of 1,4-phenylene glycol, bisphenol A, an ethylene oxide adduct of bisphenol A, and a propylene oxide adduct.

When the cushion layer is formed, a crosslinked structure may be imparted to the layer by adding isocyanate, melamine, epoxy or the like.

The dynamic hardness of the cushion layer can be changed by the number average molecular weight of the resin used and the amount of the crosslinking agent added. The number average molecular weight of the resin and the amount of the crosslinking agent added are selected so that the dynamic hardness is in the range of 0.005 to 2. The reduced viscosity, which is a measure of the molecular weight of the resin, is preferably in the range of 0.05 to 5, and the amount of the crosslinking agent added is preferably in the range of 0.1 to 80% by weight based on the resin. Generally, a resin having a reduced reduced viscosity has a higher crosslinking density, or a resin having a larger amount of a crosslinking agent has a stronger crosslinking effect. On the other hand, the higher the reduced viscosity, the lower the cross-linking density, or the smaller the amount of the cross-linking agent, the lower the cross-linking effect.

In order to sufficiently exert the impact relaxation effect, the thickness of the cushion layer having a dynamic hardness of 0.005 to 2 is preferably in the range of 2 to 100 μm, more preferably in the range of 5 to 90 μm. is there. 2-1 thickness
When the thickness is 00 μm, the effect of alleviating the impact can be sufficiently exhibited and the softness is moderate, so that there is no trouble in the touch panel assembling process.

For laminating the cushion layer on the transparent plastic film layer, it is suitable to use a coating method. Coating methods include air doctor coating, knife coating, rod coating, forward rotation roll coating, reverse roll coating, gravure coating,
A kiss coat method, a bead coat method, a slit orifice coat method, a cast coat method, or the like is used. When imparting a crosslinked structure, energy may be applied by heating or ultraviolet irradiation after lamination.

The transparent conductive thin film layer in the present invention is not particularly limited as long as it is a material having both transparency and conductivity. Representative examples are indium oxide, zinc oxide, tin oxide, indium-tin composite oxide, tin-antimony composite oxide, zinc-aluminum composite oxide,
Examples of the thin film include an indium-zinc composite oxide and an indium-zinc-gallium composite oxide. It is known that these compound thin films can be made into transparent conductive thin films having both transparency and conductivity under appropriate conditions.

The thickness of the transparent conductive thin film layer is from 40 to
It is preferably in the range of 8000 °, more preferably 50 to
5000 $. The thickness of the transparent conductive thin film layer is 40 to 8
In the case of 000 °, a continuous thin film is easily formed, good conductivity is exhibited, and transparency is satisfactory.

The transparent conductive thin film layer is formed by a known method, for example, a vacuum deposition method, a sputtering method, a CVD method, an ion plating method, a spray method, or the like. Choose a method.

For example, in the case of the sputtering method, an ordinary sputtering method using a compound, a reactive sputtering method using a metal target, or the like is used. At this time, oxygen, nitrogen, water vapor or the like may be introduced as a reactive gas, or means such as ozone addition or ion assist may be used in combination. Further, as long as the object of the present invention is not impaired, the substrate may be heated or cooled, or a bias such as direct current, alternating current, or high frequency may be applied to the substrate. Evaporation method, CVD
The same applies to the case where another creation method such as a method is adopted.

FIG. 1 shows an embodiment of the transparent conductive film of the present invention. In FIG. 1, 101 is a transparent conductive film,
11 is a transparent plastic film layer, 12 is a cushion layer, and 14 is a transparent conductive thin film layer.

In the transparent conductive film of the present invention, a transparent resin layer may be provided between the cushion layer and the transparent conductive thin film layer. When the transparent conductive thin film is formed on a transparent resin layer having shape retention, pen input durability is further improved.

The resin used to form the transparent resin layer includes polyester resin, polyamide resin, polyimide resin, polyamideimide resin, polyacryl resin,
Polyurethane resins, silicone resins, and the like are listed.
These resins may be copolymerized or blended in small amounts with other resins. When forming the transparent resin layer, a crosslinked structure may be imparted to the layer by adding isocyanate, melamine, epoxy or the like.

As the polyester resin used for forming the transparent resin layer, the same polyester resin as used for forming the cushion layer can be used. In addition, it is essential to use trimellitic anhydride as an acid component in the polyamideimide resin.

Acid components which may be copolymerized in addition to trimellitic anhydride include, for example, oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, cyclohexanedicarboxylic acid and the like. Aliphatic,
Or an alicyclic dicarboxylic acid, isophthalic acid, terephthalic acid, diphenylmethane-4,4′-dicarboxylic acid, diphenylether-4,4′-dicarboxylic acid, bis [(4-carboxy) phthalimide] -4,4′-diphenylether, Aromatic dicarboxylic acids such as bis [(4-carboxy) phthalimide] -α, α-meta-xylene, butane-1,2,4-tricarboxylic acid, benzene-
1,2,4-tricarboxylic acid, naphthalene-1,2,4
-Tricarboxylic acids such as tricarboxylic acids, and their anhydrides, pyromellitic acid, benzophenonetetracarboxylic acid, benzene-1,2,3,4-tetracarboxylic acid, biphenyltetracarboxylic acid, naphthalenetetracarboxylic acid, perylene- Tetracarboxylic acids such as 3,4,9,10-tetracarboxylic acid, ethylene glycol bis (anhydrotrimellitate), propylene glycol bis (anhydrotrimellitate), and 3,3 ′, 4,4′-oxydiphthalic acid Acids and their dianhydrides. These are used alone or as a mixture of two or more. The acid component which may be copolymerized is used within a range in which the object effect of the present invention can be achieved.
0 mol% or less, preferably 30 mol% or less.

As the diamine component, isophoronediamine, m-xylylenediamine, p-xylylenediamine, 1,3-dicyclohexylenediamine, 1,4-dicyclohexylenediamine, or a corresponding diisocyanate alone or It is essential to use as a mixture of two or more.

Further, 1,4-bis (4-aminophenoxy) benzene and 1,3-bis (4
-Aminophenoxy) benzene, 1,3-bis (3-aminophenoxybenzene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane,
Bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (2-aminophenoxy) phenyl] sulfone, 3,3′-diaminodiphenylsulfone 4,4'-diaminodiphenylsulfone, 4,4 '
-[1,3-phenylenebis (1-methylethylidene)] bisaniline, 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bisaniline, 3,
3 '-[1,3-phenylenebis (1-methylethylidene)] bisaniline, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, m-phenylenediamine, p-phenylenediamine , Oxydianiline, methylenedianiline, hexafluoroisopropylidenedianiline, 1,4-naphthalenediamine, 1,5-naphthalenediamine, 2,6-
Naphthalenediamine, 2,7-naphthalenediamine,
2,2′-bis (4-aminophenyl) hexafluoropropane, 4,4′-diaminodiphenyl ether,
3,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, hexamethylenediamine, tetramethylenediamine, 5-amino-1- (4′-aminophenyl) -1,3,3′-trimethylindane, 3,
4'-diaminodiphenyl ether, isopropylidene dianiline, 3,3'-diaminobenzophenone, 4,
4'-diaminocyclohexyl, o-tolidine, 2,4
-Tolylenediamine, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide,
6-amino-1- (4'-aminophenyl) -1,3,3
3-Trimethylindane or a corresponding diisocyanate may be polymerized. These can be polymerized alone or as a mixture of two or more. The diamine that may be copolymerized is used within a range that does not impair the properties of the polyamideimide of the present invention, but is usually 50 mol% or less, preferably 30 mol% or less, based on all diamine components.

The polyamideimide resin can be produced by a usual method such as an isocyanate method or an acid chloride method, but the isocyanate method is industrially advantageous.
In the case of the isocyanate method, as an organic solvent that can be used,
Amide-based organic solvents such as N, N-dimethylformamide, N, N-methylacetamide, N, N-diethylacetamide, N, N-dimethylmethoxyacetamide, N-methyl-2-pyrrolidone, hexamethylphosphamide; Lactam organic solvents such as -methylcaprolactam, urea organic solvents such as 1,3-dimethyl-2-imidazolidinone and tetramethylurea, 1,2-dimethoxyethane, 1,2-bis (2-methoxyethoxy) Hydrocarbon organic solvents such as ethane and bis [2- (2-methoxyethoxy) ethane], bis (2-methoxyethyl) ether, bis [2- (2-methoxyethoxy) ethyl]
Ether, 1,3-dioxane, 1,4-dioxane,
Tetrahydrofuran, ether organic solvents such as diglyme, ester organic solvents such as γ-butyrolactone,
Pyridine, pyridine-based organic solvents such as picoline, dimethylsulfoxide, dimethylsulfone, sulfur-based organic solvents such as sulfolane, nitromethane, nitroethane, nitro-based organic solvents such as nitrobenzene, nitrile-based organic solvents such as acetonitrile, and the like. It is not limited to. These organic solvents can be used alone or in a mixture of two or more.

The reaction temperature is usually preferably from 50 to 200 ° C. The reaction is a catalyst for the reaction between the isocyanate and the active hydrogen compound, for example, tertiary amines, alkali metal compounds,
Alkaline earth metal compounds, cobalt, titanium, tin,
The reaction may be performed in the presence of a metal such as zinc, a metalloid compound, or the like.

The thickness of the transparent resin layer is preferably in the range of 0.1 to 50 μm, more preferably in the range of 0.5 to 30 μm. When the thickness is in the range of 0.1 to 50 μm, the shape retention property is sufficiently exhibited, and the cushioning layer can also have a sufficient impact relaxation effect.

One embodiment of the transparent conductive film of the present invention having a transparent resin layer is shown in FIG. 2, 102 is a transparent conductive film, 11 is a transparent plastic film layer, 12 is a cushion layer, 13 is a transparent resin layer and 14
Is a transparent conductive thin film layer.

The transparent conductive film of the present invention has a hard plastic surface on the side opposite to the surface on which the transparent conductive thin film layer is provided, in order to prevent damage by a pen or the like when used for a touch panel. A coat treatment (HC) layer may be provided. As the hard coat (HC) layer, a curable resin such as a polyester resin, a urethane resin, an acrylic resin, a melamine resin, an epoxy resin, a silicon resin, and a polyimide resin is used. A cured product layer of a crosslinkable resin using isocyanate, melamine or the like is preferable. The above resins may be used alone or in combination.

The thickness of the hard coat treatment (HC) layer is as follows:
The range is preferably from 0.1 to 50 μm, and more preferably from 0.5 to 30 μm. 0. When the thickness is in the range of 1 to 50 μm, the function of the hard coat treatment is sufficiently exhibited, and the formation rate of the HC layer is not significantly reduced, so that good results can be obtained in terms of productivity.

As a method of laminating a hard coat treatment (HC) layer, the above resin is coated on the surface of the transparent conductive film opposite to the surface provided with the transparent conductive thin film layer by a gravure method.
After coating by reverse method, die method, etc.
Curing is performed by applying energy such as heat, ultraviolet rays, and electron beams.

FIG. 3 shows an embodiment of the transparent conductive film of the present invention having an HC layer. 3, 103 is a transparent conductive film, 11 is a transparent plastic film layer, 1
2 is a cushion layer, 13 is a transparent resin layer, 14 is a transparent conductive thin film layer, and 15 is an HC layer.

The transparent conductive film of the present invention has an antiglare (AG) layer on the surface of the transparent plastic film layer opposite to the surface on which the transparent conductive thin film layer is provided, in order to improve the visibility of the touch panel. May be provided. The anti-glare treatment (AG) layer is formed by coating a curable resin and drying, then forming irregularities on the surface with an embossing roll, and thereafter, curing by applying energy such as heat, ultraviolet rays, and electron beams. Preferred curable resins include polyester resins, urethane resins, acrylic resins, melamine resins, epoxy resins, silicone resins, polyimide resins, and the like, and these may be used alone or as a mixture.

The thickness of the anti-glare (AG) layer is 0.1 to 5
The range is preferably 0 μm, more preferably 0.5 to 3 μm.
The range is 0 μm.

FIG. 4 shows an embodiment of the transparent conductive film of the present invention having an AG layer. In FIG. 4, 104 is a transparent conductive film, 11 is a transparent plastic film layer, 1
2 is a cushion layer, 13 is a transparent resin layer, 14 is a transparent conductive thin film layer, and 16 is an AG layer.

The transparent conductive film of the present invention has a transparent plastic film layer on the surface opposite to the surface on which the transparent conductive thin film layer is provided, in order to further improve the visible light transmittance when used as a touch panel. The anti-reflection treatment (A
R) A layer may be provided. In the anti-reflection treatment (AR) layer,
It is preferable to form a material having a refractive index different from the refractive index of the transparent plastic film layer as a single layer or a multilayer of two or more layers. When the antireflection treatment (AR) layer has a single-layer structure, it is preferable to use a material having a smaller refractive index than the transparent plastic film layer. In the case of a multilayer structure of two or more layers, a layer having a refractive index higher than that of the plastic film layer is used for a layer adjacent to the plastic film layer, and a layer having a lower refractive index is used for a layer above the plastic film layer. It is good to choose the material. The material constituting such an anti-reflection treatment (AR) layer is not particularly limited as long as it satisfies the above-mentioned relationship of the refractive index, whether it is an organic material or an inorganic material. For example, CaF ₂ , MgF ₂ , NaAi
F ₄ , SiO ₂ , ThF ₄ , ZrO ₂ , Nd ₂ O ₃ , S
It is preferable to use a dielectric such as nO ₂ , TiO ₂ , CeO ₂ , ZnS, and In ₂ O ₃ .

The anti-reflection (AR) layer is formed by a vacuum evaporation method,
It can be formed by a dry coating process such as a sputtering method, a CVD method, or an ion plating method, or a wet coating process such as a gravure method, a reverse method, or a die method.

Antireflection treatment (AR) layer thickness d (μm)
When the refractive index of the material constituting the layer is n and the center wavelength of light entering the AR layer is λ (nm), it is preferable that the relationship of n · d = λ / 4 is satisfied.

FIG. 5 shows an embodiment of the transparent conductive film of the present invention having an AR layer. 5, 105 is a transparent conductive film, 11 is a transparent plastic film layer, 1
2 is a cushion layer, 13 is a transparent resin layer, 14 is a transparent conductive thin film layer, and 17 is an AR layer having a three-layer structure.

Further, the hard coat treatment (HC)
Prior to lamination of a layer, an antiglare treatment (AG) layer and an antireflection treatment (AR) layer, a corona discharge treatment, a plasma treatment, a sputter etching treatment, an electron beam irradiation treatment, and an ultraviolet irradiation are applied to the plastic film layer as pretreatments. Known treatments such as treatment, primer treatment, and easy adhesion treatment may be performed.

The transparency of the transparent conductive film of the present invention is as follows:
The light transmittance (%) measured by the integrating sphere light transmittance method specified in JIS K 7105 is preferably 80% or more, more preferably 85% or more. Further, the conductivity of the film is a surface resistivity (Ω / □) measured by a four-terminal method in accordance with JIS K 7194, preferably 50.
-5000 Ω / □, more preferably 100-3000
Ω / □. The thickness of the film is preferably from 12 to 450 μm, more preferably from 15 to 300 μm.

The transparent conductive film of the present invention is used as a liquid crystal display panel, an EL display panel, and a touch panel. In particular, it can be suitably used as a touch panel. FIG. 6 shows an embodiment of a touch panel using the transparent conductive film of the present invention. In a touch panel 4 in which a pair of panel plates 102 and 6 are arranged via a spacer 3 so that the transparent conductive thin film layers 14 and 14a face each other, a transparent plastic film layer 11 and a cushion layer 12 are used as one panel plate. The transparent conductive film 102 of the present invention comprising the transparent resin layer 13 and the transparent conductive thin film layer 14 is used.
a and a glass plate 2 are used. When touch panel 4 is used to input characters from pen 5 on the transparent plastic film layer 11 side,
The transparent conductive thin film layer 1 opposing by pressing from the pen 5
4 and 14a come into contact with each other and are electrically turned on, and the pen 5
On the touch panel 4 can be detected. By continuously and accurately detecting the pen position, characters can be input from the locus of the pen 5. At this time, since the panel plate on the pen contact side is the transparent conductive film 102 of the present invention, the touch panel is excellent in pen input durability, and therefore, can stably detect the pen position for a long time.

In FIG. 6, the other panel plate is
Although the transparent conductive thin film layer 14a is laminated on the glass substrate 2, the substrate is not limited to glass and can be used without any particular limitation as long as it is transparent. A transparent plastic film or another panel plate can be used in the present invention. May be used.

[0054]

EXAMPLES The present invention will be described more specifically based on the following examples. Example 1 The transparent conductive film 101 shown in FIG. 1 was manufactured as follows. A polyethylene terephthalate film (A4100, manufactured by Toyobo Co., Ltd.) having a thickness of 188 μm was used as the transparent plastic film layer 11. The light transmittance was 92%.

A polyester resin was laminated as a cushion layer 12 on the plastic film layer 11. This polyester resin was synthesized as follows. That is, in an autoclave equipped with a thermometer and a stirrer,
130 parts by weight of terephthalic acid, 56 parts by weight of isophthalic acid,
6 parts by weight of azelaic acid, 3 parts by weight of trimellitic acid, 159 parts by weight of ethylene glycol, and 30 parts by weight of neopentyl glycol are charged and heated at 180 to 230 ° C. for 120 parts.
The mixture was heated for one minute to perform a transesterification reaction. Next, the temperature of the reaction system was raised to 240 ° C., and the reaction was continued at a system pressure of 1 to 10 mmHg to obtain a copolymerized polyester resin (Example 1-).
1). Two more types of copolymerized polyester resins having different molecular weights (Example 1-2 and Example 1-3) were obtained. Table 1 shows the reduced viscosities of these resins. 340 parts by weight of the obtained polyester resin, 150 parts by weight of methyl ethyl ketone, 140 parts by weight of tetrahydrofuran, and Nippon Polyurethane Industry Co., Ltd .: Coronate L 15 as a curing agent
The mixture consisting of parts by weight was coated on the plastic film layer 11 by a knife coating method. 120 ° C1
After drying for 0 minutes, the mixture was cured by heating at 130 ° C. for 1 hour to form a cushion layer 12 having a thickness of 30 μm.

The transparent conductive thin film layer 14 having a thickness of 250 mm was formed on the cushion layer 12 by high frequency magnetron sputtering using indium tin composite oxide as a target.
To form three types of transparent conductive films 101.
The sputtering was performed at a degree of vacuum of 3 × 10 ⁻³ Torr.
r, gas as Ar 60 sccm, O _{2 2} sccm
Shed. During the formation of the transparent conductive thin film layer, the substrate comprising the transparent plastic film layer 11 and the cushion layer 12 was kept at room temperature without heating or cooling.

Using the obtained transparent conductive film,
A touch panel was manufactured. That is, the obtained transparent conductive film 101 is used as one panel plate, and the other panel plate is formed on a glass substrate by the same method as described above.
A transparent conductive thin film layer having a thickness of 0 mm was used. The two panel plates were arranged via epoxy beads (spacers) having a diameter of 30 μm so that the transparent conductive thin film layers faced each other, to produce a touch panel.

Example 2 A transparent conductive film 102 shown in FIG. 2 was manufactured as follows. A polyethylene terephthalate film (A4100, manufactured by Toyobo Co., Ltd.) having a thickness of 188 μm was used as the transparent plastic film layer 11.

On the plastic film layer 11, the same polyester resin (3 types) as in Example 1 (Example 2)
1, the cushion layer 12 was laminated using Example 2-2 and Example 2-3). That is, a mixture consisting of 340 parts by weight of the same resin as the polyester resin used in Example 1, 150 parts by weight of methyl ethyl ketone, 140 parts by weight of tetrahydrofuran, and 15 parts by weight of Coronate HX manufactured by Nippon Polyurethane Industry Co., Ltd. as a curing agent was knife-coated. It was coated on the plastic film layer 11 by a method. After drying at 120 ° C. for 10 minutes, the mixture was cured by heating at 130 ° C. for 1 hour to form a cushion layer 12 having a thickness of 20 μm.

Further, a transparent resin layer 13 is further formed thereon.
A polyester resin was laminated as a layer having a thickness of 10 μm. This resin is manufactured by Toyobo Co., Ltd. Byron 296
30 parts by weight and 5 parts by weight of Sumitex Resin M-415 manufactured by Sumitomo Chemical Co., Ltd. were dissolved in tetrahydrofuran to prepare a 40% by weight solution. Using this solution, a film is formed by a cast coat method.
Dry at 30 ° C. for 5 minutes and cure at 120 ° C. for 10 minutes.

On the transparent resin layer 13, a transparent conductive thin film layer 14 having a thickness of 300 mm was formed by high frequency magnetron sputtering using indium tin composite oxide as a target. I got
In the above sputtering, the degree of vacuum was 1 × 10 ⁻³ Torr.
r, gas as Ar 30 sccm, O _{2 1} scc
m. During the formation of the transparent conductive thin film layer, the substrate composed of the plastic film layer 11, the cushion layer 12, and the transparent resin layer 13 was not heated or cooled, and was kept at room temperature. Further, the substrate potential was set to ground.

Using the obtained transparent conductive film,
The touch panel shown in FIG. 6 was produced. That is, the transparent conductive film 102 including the transparent plastic film layer 11, the cushion layer 12, the transparent resin layer 13, and the transparent conductive thin film layer 14 is used as one panel plate, and the other panel plate is formed on the glass substrate 2 as described above. 4 in the same way as
Panel 6 having a transparent conductive thin film layer 14a having a thickness of 00 mm
Was used. The two panel boards 102 and 6 were arranged via epoxy beads (spacers) 3 having a diameter of 30 μm so that the transparent conductive thin film layers 14 and 14a faced each other, and a touch panel 4 was manufactured.

Example 3 A transparent conductive film 102 shown in FIG. 2 was manufactured as follows. A polyethylene terephthalate film (A4100, manufactured by Toyobo Co., Ltd.) having a thickness of 188 μm was used as the transparent plastic film layer 11. The cushion layer 12 was laminated on the transparent plastic film layer 11 by using the same polyester resin (three types) (Example 3-1, Example 3-2, and Example 3-3) as in Example 1. That is, 340 parts by weight of the same resin as the polyester resin used in Example 1, 150 parts by weight of methyl ethyl ketone, 140 parts by weight of tetrahydrofuran, and Coronate HX manufactured by Nippon Polyurethane Industry Co., Ltd. as a curing agent
Was coated on the plastic film layer 11 by knife coating. 12
After drying at 0 ° C. for 15 minutes, the mixture was cured by heating at 130 ° C. for 1 hour to form a cushion layer 12 having a thickness of 40 μm.

Further, a transparent resin layer 13 is further formed thereon.
The polyamideimide resin was laminated as a layer having a thickness of 10 μm. The polyamideimide resin was synthesized as follows. A reaction vessel was charged with 50 parts by weight of trimellitic anhydride, 50 parts by weight of isophorone diisocyanate, and 200 parts by weight of γ-butyrolactone, and stirred for 190 minutes in about 30 minutes.
The temperature was raised to ° C. After stirring at 190 ° C. for about 5 hours, the mixture was cooled to 150 ° C. This was diluted by adding 100 parts by weight of N-methyl-2-pyrrolidone, and further cooled to 50 ° C. or lower. After forming a film on the cushion layer 12 by the cast coating method using the obtained resin mixture, 130
Dry at 15 ° C for 15 minutes.

A transparent conductive thin film layer 14 having a thickness of 300 mm was formed on the transparent resin layer 13 by high frequency magnetron sputtering using indium tin composite oxide as a target, and three types of transparent conductive films 102 were formed. Obtained. The sputtering was performed at a degree of vacuum of 1 × 10 ⁻³ Torr.
And gas as Ar 30 sccm, O ₂ 1 sccm
Shed. During the formation of the transparent conductive thin film layer, a plastic (polyester) film layer 11, a cushion layer 12
The substrate made of the transparent resin layer 13 was not heated or cooled and was kept at room temperature. Further, the substrate potential was set to ground.

Using the obtained transparent conductive film, a touch panel as shown in FIG. 6 was produced. That is, the transparent conductive film 102 is used as one panel plate, and the other panel plate is formed on the glass substrate 2 by the same method as described above.
A transparent conductive thin film layer 14a having a thickness of 0 ° was used. The two panel boards 102 and 6 were arranged via epoxy beads (spacers) 3 having a diameter of 30 μm so that the transparent conductive thin film layers 14 and 14a faced each other, and a touch panel 4 was manufactured.

Example 4 A transparent conductive film 103 shown in FIG. 3 was obtained as follows. A 188 μm-thick polyethylene terephthalate film (A4100, manufactured by Toyobo Co., Ltd.) was used as the transparent plastic film layer 11. The same polyester resin (reduced viscosity: 0.41) as in Example 1 was laminated on the plastic film layer 11 as the cushion layer 12 in the same manner as in Example 1 (thickness: 30 μm). Further, the same polyamide imide resin as in Example 3 was laminated thereon as a transparent resin layer 13 in the same manner as in Example 3 (thickness: 10 μm). Transparent plastic film layer 11
A hard coat treatment (HC) layer was provided on the surface opposite to the surface on which the transparent resin layer 13 was formed. As a hard coating agent, an ultraviolet curable resin composition obtained by adding 4 parts by weight of benzophenone to 100 parts by weight of an epoxy acrylic resin was used, and a film was formed by a reverse coating method.
The composition was cured by irradiating 0 mJ / cm ² with ultraviolet rays. The thickness of the layer after curing was 5 μm.

On the transparent resin layer 13, an indium tin composite
Using an oxide as a target, a high-frequency magnetron spa
A 300Å thick transparent conductive thin film layer 14 is formed by the
A transparent conductive film 103 was obtained by forming a film. Spatter
The ring has a vacuum of 1 × 10 ^-3Torr and gas
Ar 30 sccm, O_TwoThe flow was 1 sccm. Also,
Transparent plastic film layer 11, cushion layer 12,
The substrate composed of the transparent resin layer 13 and the HC layer is
Room temperature was maintained without heating or cooling.

The obtained transparent conductive film 103 was used as one panel plate, and as the other panel plate, a transparent conductive thin film layer having a thickness of 400 mm formed on a glass substrate in the same manner as described above was used. The two panel plates were arranged via epoxy beads (spacers) having a diameter of 30 μm such that the transparent conductive thin film layer 14 was opposed to each other, thereby producing a touch panel.

Example 5 A transparent conductive film 104 shown in FIG. 4 was obtained as follows. A polyethylene terephthalate film (manufactured by Toyobo Co., Ltd .: A41OO) having a thickness of 188 μm was used as the transparent plastic film layer 11. Example 1 as a cushion layer 12 on a plastic film layer 11
The same polyester resin (reduced viscosity: 0.41) was laminated in the same manner as in Example 1 (thickness: 30 μm). Further, the same polyamide imide resin as in Example 3 was laminated thereon as a transparent resin layer 13 in the same manner as in Example 3 (thickness: 10 μm). Transparent plastic film layer 11
An anti-glare (AG) layer was provided on the surface opposite to the surface on which the transparent resin layer 13 was formed. As a coating agent, a UV-curable resin composition obtained by adding 2 parts by weight of benzophenone to 100 parts by weight of an epoxy acrylic resin is used, and after forming a film by a reverse coating method, preliminary drying is performed at 80 ° C. for 5 minutes, and the surface is embossed with an embossing roll. Irregularities were formed and cured by irradiation with ultraviolet rays at 500 mJ / cm ² . The thickness of the layer after curing was 5 μm.

An indium tin composite is formed on the transparent resin layer 13.
Using an oxide as a target, a high-frequency magnetron spa
A 300Å thick transparent conductive thin film layer 14 is formed by the
A transparent conductive film 104 was obtained by forming a film. Spattery
The vacuum method is 1 × 10 ^-3Torr and gas
Ar 30 sccm, O_TwoThe flow was 1 sccm. Also,
Transparent plastic film layer 11, cushion layer 12,
The substrate composed of the transparent resin layer 13 and the AG layer is processed during film formation.
Room temperature was maintained without heat or cooling.

The obtained transparent conductive film 104 was used as one panel plate, and the other panel plate was formed by forming a transparent conductive thin film layer having a thickness of 400 mm on a glass substrate in the same manner as described above. The two panel plates were arranged via epoxy beads (spacers) having a diameter of 30 μm so that the transparent conductive thin film layers faced each other, to produce a touch panel.

Example 6 A transparent conductive film 104 shown in FIG. 4 was obtained as follows. A polyethylene terephthalate film (A4100, manufactured by Toyobo Co., Ltd.) having a thickness of 188 μm was used as the transparent plastic film layer 11. Example 1 as a cushion layer 12 on a plastic film layer 11
The same polyester resin (reduced viscosity: 0.41) was laminated in the same manner as in Example 1 (thickness: 30 μm). Further, the same polyamide imide resin as in Example 3 was laminated thereon as a transparent resin layer 13 in the same manner as in Example 3 (thickness: 10 μm). A thickness 730 is formed on the surface of the transparent plastic film layer 11 opposite to the surface on which the transparent resin layer 13 is formed.
Å, a Y ₂ O ₃ layer with a refractive index of 1.89, a thickness of 1200 °, a TiO ₂ layer with a refractive index of 2.3, and a refractive index of 1.4 with a thickness of 940 °.
An anti-reflection (AR) layer was formed by forming each of the SiO ₂ layers 6 by a high frequency sputtering method. When each of these dielectric thin films is formed, the degree of vacuum is 1 ×
10 ⁻³ Torr, Ar gas 30 sccm,
O _{2 was} flowed at 1 sccm. The substrate composed of the transparent plastic film layer 11, the cushion layer 12, and the transparent resin layer 13 was kept at room temperature without heating or cooling during film formation.

On the transparent resin layer 13, indium tin compound
High-frequency magnetrons using composite oxides as targets
The transparent conductive thin film layer 14 having a thickness of 300 mm is formed by the sputtering method.
Was formed to obtain a transparent conductive film 104. Spatter
The ring has a vacuum of 1 × 10 ^-3Torr and gas
Ar 30 sccm, O_TwoThe flow was 1 sccm. Also,
Transparent plastic film layer 11, cushion layer 12,
The substrate 1 composed of the transparent resin layer 13 and the AR layer is
Room temperature was maintained without heating or cooling.

The obtained transparent conductive film 104 was used as one panel plate, and the other panel plate was formed by forming a transparent conductive thin film layer having a thickness of 400 mm on a glass substrate by the same method as described above. . The two panel plates were arranged via epoxy beads (spacers) having a diameter of 30 μm so that the transparent conductive thin film layers faced each other, to produce a touch panel.

Comparative Example 1 A transparent conductive film was obtained in the same manner as in Example 1 except that the cushion layer was not formed. A touch panel was produced in the same manner as in Example 1 using the obtained film.

Comparative Example 2 A transparent conductive film was obtained in the same manner as in Example 1 except that a cushion layer (dynamic hardness: 0.002) was formed using a polyester resin having a reduced viscosity of 3.8. Using the obtained film, a touch panel was manufactured in the same manner as in Example 1.

Comparative Example 3 A transparent conductive film was obtained in the same manner as in Example 1 except that a cushion layer (dynamic hardness: 2.3) was formed using a polyester resin having a reduced viscosity of 0.08. Using the obtained film, a touch panel was manufactured in the same manner as in Example 1.

Comparative Examples 4 and 5 A polyethylene terephthalate film (A4100, manufactured by Toyobo Co., Ltd.) having a thickness of 188 μm was used as a transparent plastic film layer. A reduced viscosity of 3.8 (Comparative Example 4) or 0.08 on the transparent plastic film layer
Coating was performed in the same manner as in Example 2 except that the polyester resin of (Comparative Example 5) was used to form a cushion layer (dynamic hardness: 0.001). A polyamideimide resin layer (thickness: 10 μm) was laminated on the cushion layer as a transparent resin layer in the same manner as in Example 3. A transparent conductive thin film was formed on the transparent resin layer in the same manner as in Example 3 to obtain a transparent conductive film. Using the obtained film, a touch panel was manufactured in the same manner as in Example 1.

The light transmittance and surface resistivity of the transparent conductive films of Examples 1 to 6 and Comparative Examples 1 to 5 were measured by the following methods. In addition, a pen input durability test was performed on the touch panels manufactured using the transparent conductive films of Examples 1 to 6 and Comparative Examples 1 to 5.

<Surface Resistivity> The surface resistivity was measured by a four-terminal method according to JIS K 7194. As a measuring device, Mitsubishi Yuka Co., Ltd .: Lotest AMCP-T400 was used.

<Light Transmittance> The light transmittance was measured by an integrating sphere light transmittance method based on JIS K 7105. As a measuring instrument, NDH-1001DP manufactured by Nippon Denshoku Industries Co., Ltd. was used.

<Dynamic Hardness> The dynamic hardness of the resin constituting the cushion layer was measured using a Shimadzu Dynamic Ultra-Micro Hardness Tester DUH-201 manufactured by Shimadzu Corporation. The indenter used was a 115 ° triangular cone indenter. The value when the indentation amount of the indenter into the resin was 0.5 μm was defined as the dynamic hardness of the resin.

<Reduced Viscosity> The reduced viscosity of the resin constituting the cushion layer before crosslinking was measured using a mixed solvent of phenol and tetrachloroethane (6: 4, volume ratio). The temperature of the viscosity tube was set at 30 ° C., and the falling time of the mixed solvent was
And the falling time t of the solution in which the resin was dissolved in the mixed solvent was measured, and the reduced viscosity was calculated by (t-to) / to.

<Pen Input Durability Test> A touch pen (Hyperelectronic Notebook DB-Z touch pen manufactured by Sharp Corporation) with a pen tip radius of 0.8 mm made of polyacetal resin was used from the side of the panel plate made of a transparent conductive film. Plotter (Roland Co., Ltd .: DXY-115)
According to 0), 100,000 characters of 2 cm square size katakana characters A to A were written. At this time, the pen load was 200 g, and the character writing speed was 2,000 characters / hour. Before and after the pen input test, the position detection accuracy of the touch pen was measured by the deviation of the voltage linearity of the touch panel. A constant voltage of 5 V was applied to the electrode portions arranged above and below the panel plate, and the rate at which the applied voltage changed the most from the linear change from the upper electrode to the lower electrode was measured. Table 1 shows the results.

[0086]

[Table 1]

From the results shown in Table 1, it can be seen that the transparent conductive film of the present invention has extremely excellent conductivity and transparency, and that the touch panel using the transparent conductive film of the present invention has extremely excellent pen input durability. I understand.

[0088]

The transparent conductive film of the present invention is extremely excellent in pen input durability due to the shock absorbing effect of the cushion layer provided between the plastic film layer and the transparent conductive thin film layer. A touch panel having extremely excellent detection stability can be provided.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of the transparent conductive film of the present invention, showing a layer configuration of the transparent conductive film produced in Example 1.

FIG. 2 is a view showing one embodiment of the transparent conductive film of the present invention, showing a layer configuration of the transparent conductive films produced in Examples 2 and 3.

FIG. 3 is a view showing one embodiment of the transparent conductive film of the present invention, showing a layer configuration of the transparent conductive film produced in Example 4.

FIG. 4 is a view showing one embodiment of the transparent conductive film of the present invention, showing a layer configuration of the transparent conductive film manufactured in Example 5.

FIG. 5 is a view showing one embodiment of the transparent conductive film of the present invention, showing a layer configuration of the transparent conductive film produced in Example 6.

FIG. 6 is an embodiment of the touch panel of the present invention,
FIG. 6 is a diagram showing a cross section of a touch panel manufactured in Examples 2 and 3.

[Explanation of symbols]

101, 102, 103, 104, 105 Transparent conductive film 11 Transparent plastic film layer 12 Cushion layer 13 Transparent resin layer 14 Transparent conductive thin film layer 15 Hard coat treatment (HC) layer 16 Anti-glare treatment (AG) layer 17 Anti-reflection Processing (AR) layer 2 Glass substrate 3 Spacer (epoxy beads) 4 Touch panel 5 Pen 6 Transparent conductive panel board

Claims (6)

[Claims] 1. A transparent plastic film layer, having a dynamic hardness of 0.3 formed on one surface of the film layer.
A transparent conductive film comprising a cushion layer of 005 to 2 and a transparent conductive thin film layer formed on the cushion layer. 2. The transparent conductive film according to claim 1, further comprising a transparent resin layer formed between the cushion layer and the transparent conductive thin film layer. 3. The transparent conductive film according to claim 1, further comprising a hard coat treatment layer formed on a surface of the transparent plastic film layer opposite to a surface on which the transparent conductive thin film layer is formed. 4. The transparent conductive film according to claim 1, further comprising an antiglare treatment layer formed on the surface of the transparent plastic film layer opposite to the surface on which the transparent conductive thin film layer is formed. 5. The transparent conductive film according to claim 1, further comprising an antireflection treatment layer formed on the surface of the transparent plastic film layer opposite to the surface on which the transparent conductive thin film layer is formed. 6. A touch panel in which a pair of panel plates having a transparent conductive thin film layer is disposed via a spacer so that the transparent conductive thin film layers face each other, and at least one of the panel plates is provided. A touch panel comprising the transparent conductive film according to any one of claims 1 to 5.