WO2000079544A1 - Transparent conductive film and electroluminescence panel comprising the same - Google Patents

Abstract

A transparent conductive film comprising a biaxially-oriented polyester film and a transparent conductive thin film formed on one side of the polyester film. A coating layer is formed at least on one side of the polyester film. The total flux transmittance is 90 % or more. The three-dimensional central surface average roughness (SRa) is 0.002 to 0.010 νm. The increase of the haze value when the transparent conductive film is heat-treated at 150 °C for three hours is 2.0 % or less. The transparency is excellent and hardly changes after the heat-treatment during the post-processing. When the transparent conductive film is used as an electroluminescence (EL) panel, the appearance defects such as whitening are few, and the visibility is excellent. An electroluminescence (EL) panel comprising such a transparent conductive film is also provided.

Description

 Description Transparent conductive film and electroluminescent panel using the same

 The present invention relates to a transparent conductive film using a biaxially oriented polyester film having a coating layer, and an electroluminescence (hereinafter abbreviated as EL) panel using the same. Background art

 Transparent conductive films formed by forming a transparent and low-resistance compound thin film on a plastic film are used in applications that use the conductivity, such as flat panel displays such as liquid crystal displays and EL displays, and transparent electrodes for touch panels. Widely used in field applications.

 Typical examples of the transparent conductive thin film include tin oxide, indium oxide, indium tin oxide, zinc oxide, and the like. Substrates such as polyethylene terephthalate and the like Plastic film is used.

 In recent years, with the spread of mobile phones and personal digital assistants, EL panels have attracted attention as backlights for these liquid crystal displays. In addition, EL panels have low power consumption during light emission, and are suitable as light sources for portable devices. Furthermore, with the enlargement and higher definition of the display unit, there is a growing demand for higher brightness and reduced appearance defects of EL panels.

Conventionally, an EL panel is manufactured by a process of sequentially printing an EL light emitting layer, a dielectric layer, a back electrode layer, and an insulating layer on a transparent conductive thin film of a transparent conductive film. Further, by applying an AC voltage of about 400 Hz between the transparent conductive thin film and the back electrode, a voltage is applied to the light emitting layer to emit light. As the applied voltage increases, the light emission luminance increases. Needless to say, the higher the light transmittance of the transparent conductive film, the higher the luminance of the EL panel. In response to such demands, conventionally used transparent conductive films have the following problems.

 Generally, particles are contained in the polyester film to improve the slipperiness. However, when these particles are contained in a polyester film, the light transmittance of the polyester film tends to be impaired. In addition, when the polyester film does not contain particles or contains only a small amount of particles so as not to impair the light transmittance, it is generally necessary to include the particles in the coating layer to improve the slipperiness. is there. At that time, in order to ensure transparency, it is necessary to use fine particles having an extremely small average particle size smaller than the wavelength of visible light. However, with only such fine particles having a small average particle size, although the transparency is good, the slipperiness is insufficient. For this reason, the film surface is likely to be damaged by a roll that comes into contact in a post-process such as a coating process.

 In the production of EL panels, it is necessary to perform heat treatment at 120 to 150 ° C in a printing process such as circuit processing. However, the conventional transparent conductive film based on a biaxially oriented polyester film has a problem that the haze value increases and white appearance defects occur after the heat treatment. Since these deteriorate the visibility and quality of the EL panel, improvement of the above-mentioned problems has been desired.

 The present invention is intended to solve the above-mentioned conventional problems. The first purpose is to have high light transmittance, excellent scratch resistance, and transparency even after heat treatment in post-processing. The object of the present invention is to provide a transparent conductive film having a small change in the film thickness. A second purpose is to provide an EL panel that has very few external defects such as whitening and has excellent visibility. Disclosure of the invention

 The present invention has been made in view of the above situation, and a transparent conductive film and an electroluminescence panel using the same that can solve the above problems are as follows. .

That is, the first invention of the present invention is a transparent conductive film in which a transparent conductive thin film is laminated on one surface of a biaxially oriented polyester film, A coating layer is formed on at least one side of the film, the total light transmittance is 90% or more, and the three-dimensional center plane average surface roughness (SR a) of the coating layer surface is 0.002 to 0.01. 0, and the haze value before and after the heat treatment when the transparent conductive film is heat-treated at 150 ° C. for 3 hours is 2.0% or less.

 A second invention is the first invention, wherein when the transparent conductive film is heated at 150 ° C. for 2 hours, a haze value increase before and after the heat treatment is 0.5% or less. It is a transparent conductive film of the description.

 A third invention is the transparent conductive film according to the first invention, wherein a total light transmittance of the transparent conductive film is 84% or more.

 A fourth invention is the transparent conductive film according to the first invention, wherein the resin composition constituting the coating layer contains a copolymerized polyester resin and a polyurethane resin.

 In a fifth aspect, the resin composition constituting the coating layer includes a copolymerized polyester resin containing a branched glycol component and a resin containing a block-type isocyanate group. Is a transparent conductive film.

 A sixth invention is the transparent conductive film according to the first invention, wherein the content of the cyclic trimer in the biaxially stretched polyester film is 500 ppm or less.

 A seventh invention is the polyester film according to the first invention, wherein a thin film layer made of a crosslinked resin is provided on a surface of the transparent conductive film on which the transparent conductive thin film is not formed. .

 An eighth invention is a transparent conductive film, characterized in that the cross-linkable resin according to the seventh invention comprises an isocyanate-based resin and an epoxy or epoxy-based resin. A ninth invention is the transparent conductive film according to the first invention, wherein the thickness of the transparent conductive thin film is 80 nm or more.

According to a tenth aspect, the transparent conductive film according to the ninth aspect has a warpage of 2 mm or less in a size of 3 O mm x 3 O mm when heated at 150 ° C. for 3 hours. Is a transparent conductive film. The eleventh invention is the transparent conductive film according to the ninth invention, wherein a heat shrinkage when heat-treated at 150 ° C. for 3 hours is 0.2% or less.

 According to a twelfth aspect, the transparent conductive film has a maximum light transmittance in a wavelength range of 450 to 600 nm, and the maximum value of brackets is 80 to 97%. The transparent conductive film according to the ninth invention, characterized in that:

 A thirteenth aspect of the present invention is the transparent conductive film according to the thirteenth aspect, wherein the surface resistivity is 10 to 10.

 A fourteenth invention is the transparent conductive film according to the twenty-second invention, wherein a dielectric thin film is laminated on the transparent conductive thin film.

 A fifteenth invention is characterized in that a light-emitting layer, a dielectric layer, a back electrode layer, and an insulating layer are laminated in this order on the transparent conductive thin film of the transparent conductive film according to the first to fourteenth inventions. This is an electronic luminescence panel.

 A sixteenth invention is characterized in that the emission wavelength / IE of the light-emitting layer and the wavelength at which the light transmittance of the transparent conductive film according to the second invention has the highest value satisfy the following expression. This is an electroluminescent panel.

 λ I-50 nm ≤; i E ≤ 11 + 50 nm Next, embodiments of the present invention will be described in detail.

 In the present invention, the biaxially oriented polyester film is used as a base for a transparent conductive film. Examples of the raw material resin for the biaxially oriented polyester film include polyethylene terephthalate, polybutylene terephthalate, polyethylene-1,6-naphthalate, and a copolymer mainly composed of the components of these resins. Among them, polyethylene terephthalate Is particularly preferred.

When a polyester copolymer is used as the resin forming the biaxially oriented polyester film, the dicarboxylic acid component includes aliphatic dicarboxylic acids such as adipic acid and sebacic acid, terephthalic acid, isophthalic acid, phthalic acid, and 2, 6 _ Aromatic dicarboxylic acids such as naphthalene dicarboxylic acid, etc., and polyfunctional carboxylic acids such as trimellilotic acid and pyromellilotic acid are used. The glycol components include ethylene glycol, diethylene glycol, 1,4-butanediol, and propylene. Fatty acid glycols such as glycol and neopentyl glycol; aromatic glycols such as p-xylene glycol; alicyclic dalicol such as 1,4-cyclohexanedimethanol: polyethylene having an average molecular weight of 150 to 200,000 Dali call is used. Preferred copolymer proportions are less than 20%. If it exceeds 20%, the film strength, transparency and heat resistance may be poor. Further, the polyester-based resin may contain various additives. Examples of the additive include an antistatic agent, a UV absorber, and a stabilizer. It is preferable that the biaxially oriented polyester film does not contain particles from the viewpoint of transparency.

 The intrinsic viscosity of the polyester resin, which is the starting material of the biaxially oriented polyester film, is preferably in the range of 0.45 to 0.70 d1Zg. If the intrinsic viscosity is less than 0.45 d1 Zg, rupture tends to occur frequently during stretching of the polyester film. On the other hand, if the intrinsic viscosity exceeds 0.70 dl Zg, the increase in filtration pressure becomes large, and high-precision filtration tends to be difficult.

 It is necessary to provide a coating layer on at least one side of the biaxially oriented polyester film. The coating layer is preferably provided on at least one surface of the unstretched or uniaxially stretched polyester film, and then laminated by an inline coating method in which the film is stretched in at least one axis direction and heat-fixed. By incorporating fine particles of an appropriate particle size into the coating layer laminated by the in-line coating method and improving the slipperiness, it is possible to impart favorable winding properties and scratch resistance. Therefore, it is not necessary to include fine particles in the biaxially oriented polyester film, and high transparency can be maintained.

 The resin composition constituting the coating layer preferably contains a copolymerized polyester resin (A) and a polyurethane resin (B). When the copolymerized polyester resin alone is used, the adhesion to the polyester film is sufficient, but the adhesion to the acrylic resin used for the hard coat tends to be insufficient. Moreover, although the polyurethane resin alone has excellent adhesiveness with the acrylic resin, the adhesiveness with the polyester film tends to be insufficient.

It is particularly preferable that the copolymerized polyester resin (A) contains a dicarboxylic acid component and a branched glycol component as constituent components. Said branched glycol component Is, for example, 2,2-dimethyl-l, 3-propanediol, 2-methyl-l-ethyl-l, l, 3-propanediol, 2-methyl-l-butyl-l, l, 3-propanediol, 2- Methyl-2-propyl-1-1,3-propanediol, 2-methyl-1-isopropyl-1-1.3-propanediol, 2-methyl_2-n-hexyl-1,3-propanediol, 2.2 —Jetyl-1,3-propanediol, 2-ethyl-2-n-butyl-1,3-propanediol, 2-ethyl-2-n-hexyl-1,3-propanediol, 2,2- Di-n-butyl-1,3-propanediol, 2-n-butyl-12-propyl-11,3-propanediol, and 2,2-di-n-hexyl-11,3-propanediol No.

 The branched glycol component is preferably contained in a proportion of at least 10 mol%, more preferably at a proportion of at least 20 mol%, in all the glycol components. As the darichol component other than the above compounds, ethylene dalicol is most preferred. If it is a small amount, diethylene glycol, propylene glycol, butanediol, hexanediol or 1,4-cyclohexanedimethanol may be used.

 As the dicarboxylic acid component, which is another component of the copolymerized polyester resin (A), terephthalic acid and isophthalic acid are most preferable. If it is a small amount, another dicarboxylic acid, in particular, an aromatic dicarboxylic acid such as diphenyl carboxylic acid and 2,6-naltalenedicarboxylic acid may be added and copolymerized. In addition to the dicarboxylic acid component, it is preferable to use 5-sulfoisophthalic acid in the range of 1 to 10 mol% in order to impart water dispersibility. For example, sulfoterephthalic acid, 5-sulfoisophthalic acid, —Sulfonaphthalene isophthalic acid-2,7-dicarboxylic acid and 5- (4-sulfofenoxy) isophthalic acid and salts thereof.

The polyurethane resin (B) is, for example, a resin having a block-type isocyanate group, and is a heat-reactive water-soluble urethane having a terminal isocyanate group blocked with a hydrophilic group (hereinafter, abbreviated as a block). No. Examples of the blocking agent for the isocyanate group include phenols containing bisulfites and sulfonic acid groups. Alcohols, lactams, oximes and active methylene compounds.

 The blocked isocyanate groups hydrophilize or solubilize the polyurethane prepolymer. When heat energy is applied to the resin in the drying step or the heat setting treatment step after application to the film, the blocking agent is removed from the isocyanate group. It not only fixes the copolymerized polyester resin but also reacts with the terminal groups of the resin. The resin being prepared is poor in water resistance because it is hydrophilic, but when the coating, drying and heat setting are completed and the thermal reaction is completed, the hydrophilic group of the urethane resin, that is, the blocking agent, comes off and the water resistance is good. Coating film is obtained.

 Among the above blocking agents, bisulfites are most preferable as those which are suitable for heat treatment temperature and heat treatment time and are widely used industrially.

 The chemical composition of the urethane prepolymer used in the polyurethane resin (B) is as follows: (a) an organic polysocyanate having two or more active hydrogen atoms in the molecule, or at least two active hydrogen atoms in the molecule. A compound having a hydrogen atom and a molecular weight of 200 to 200,000; (b) an organic polyisocyanate having two or more isocyanate groups in the molecule; or (c) at least a molecule in the molecule. A compound having a terminal isocyanate group obtained by reacting a chain extender having two active hydrogen atoms is preferred.

 The compound (a) is generally known as a compound containing two or more hydroxyl groups, carboxyl groups, amino groups or mercapto groups at the terminal or in the molecule. Particularly preferred compounds are polyethers. Polyols and polyester ester polyols.

 Examples of the polyether polyol include, for example, alkylene oxides such as ethylene oxide and propylene oxide, or compounds obtained by polymerizing styrene oxide and epihydric hydrin, or the like, or random polymerization, block polymerization, or addition to polyhydric alcohol. There are compounds obtained by performing polymerization.

As the polyester polyol and the polyetherester polyol, linear or branched compounds are mainly mentioned. Succinic acid, adipic acid, lid To polyhydric saturated or unsaturated carboxylic acids such as maleic acid and maleic anhydride, or the carboxylic anhydrides, etc., to ethylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6- By condensing polyhydric saturated and unsaturated alcohols such as xandiol and trimethylolpropane, polyalkylene ether daricols such as relatively low molecular weight polyethylene glycol and polypropylene glycol, or a mixture of these alcohols. Obtainable.

 Further, polyester polyols include polyesters obtained from lactones and hydroxy acids, and polyether ester polyols include polyether esters obtained by adding ethylene oxide or propylene oxide to polyesters prepared in advance. Kinds can also be used.

 Examples of the organic polyisocyanate (b) include isomers of toluylene diisocyanate, aromatic diisocyanates such as 4,4-diphenylmethane diisocyanate, and xylylene diisocyanate. Alicyclic diisocyanates such as aromatic aliphatic diisocyanates, isophorone diisocyanate and 4,4-dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and 2,2,4 — Aliphatic diisocyanates such as trimethylhexamethylene diisocyanate, and polyisocyanates in which one or more of these compounds are added in advance to trimethylolpropane or the like.

 Examples of the chain extender having at least two active hydrogens of the above (c) include dalicols such as ethylene glycol, diethylene glycol, 1,4-butanediol, and 1,6-hexanediol, glycerin, trimethylolpropane, And polyhydric alcohols such as pentaerythritol, diamines such as ethylenediamine, hexamethylenediamine and piperazine; aminoalcohols such as monoethanolamine and diethanolamine; thiodiglycols such as thioethylendarcol; Or water.

In order to synthesize the urethane prepolymer, a single-stage or multi-stage isocyanate polyaddition method using the above-described chain extender is carried out at a temperature of 150 ° C or lower, preferably 70 ° C to 120 ° C. And react for 5 minutes to several hours. For active hydrogen atom The ratio of the isocyanate groups can be freely selected as long as it is 1 or more, but it is necessary that free isocyanate groups remain in the obtained urethane prepolymer. Further, the content of the free isocyanate group may be 10% by weight or less, but is preferably 7% by weight or less in consideration of the stability of the urethane polymer aqueous solution after blocking.

 The obtained urethane prepolymer is preferably subjected to blocking using bisulfite. Mix with an aqueous bisulfite solution and allow the reaction to proceed with good stirring for about 5 minutes to 1 hour. The reaction temperature is preferably set to 60 ° C or lower. Thereafter, the mixture is diluted with water to an appropriate concentration to obtain a heat-reactive water-soluble urethane composition. When the composition is used, it is adjusted to an appropriate concentration and viscosity.However, if the composition is heated to about 80 to 200 ° C, the bisulfite of the blocking agent is dissociated, and the active isocyanate group is regenerated. In addition, a polyurethane polymer is formed by a polyaddition reaction occurring within or between molecules of the prepolymer, or has a property of causing addition to another functional group.

 As an example of the resin (Β ') containing a block-type isocyanate group described above, Elastron (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is typically exemplified. The elastomeric mouth is made by blocking the isocyanate group with sodium bisulfite, and is water-soluble due to the presence of a strong hydrophilic and terminal rubamoyl sulfonate group at the molecular end.

 When a coating liquid is prepared by mixing a copolymerized polyester resin containing a branched dalicol component and a resin containing a block-type isocyanate group (Β ′) used in the present invention, the resin (Α 一) and The weight ratio of the resin (Β ′) is preferably (Α ′) :( Β1) = 90: 10 to 10:90, more preferably (Α ′) :( Β1) = 80: 20 to 20:80. Range. If the ratio of the resin (樹脂) to the weight of the solid content is less than 10% by weight, the coatability to the base film is poor, and the adhesiveness between the surface layer and the film becomes insufficient. When the ratio of the resin (Β ′) to the weight of the solid content is less than 10% by weight, practical adhesiveness cannot be obtained with a UV-curable hard coat.

In the present invention, an aqueous coating solution is used as a coating solution for forming a coating layer. preferable. Various additives such as an antistatic agent, an ultraviolet absorber, a plasticizer, a pigment, an organic filler, and a lubricant may be mixed with the composition of the aqueous coating solution as long as the adhesiveness is not impaired. Further, since the coating solution is water-based, other water-soluble resins, water-dispersible resins, emulsions and the like may be added to the coating solution as long as the adhesiveness is not impaired. A catalyst may be added to the aqueous coating solution to promote a thermal crosslinking reaction. For example, various chemicals such as inorganic substances, salts, organic substances, alkaline substances, acidic substances, and metal-containing organic compounds can be used. The substance is used. In order to adjust the pH of the aqueous solution, an alkaline substance or an acidic substance may be added.

 When the aqueous coating solution is applied to the surface of the base film, a known anionic active agent and a known nonionic surfactant are used to improve the wettability to the film and uniformly coat the coating solution. It is preferable to add a necessary amount of the agent. The solvent used for the coating solution may be mixed with alcohols such as ethanol, isopropyl alcohol and benzyl alcohol, in addition to water, until the proportion of the solvent in the total coating solution is less than 50% by weight.

Furthermore, if it is less than 10% by weight, an organic solvent other than alcohols may be mixed as long as it can be dissolved. However, the total amount of alcohols and other organic solvents in the coating liquid is preferably less than 50% by weight. When the amount of the organic solvent added is less than 50% by weight, the drying property after coating is improved, and the appearance of the coating layer becomes better than when water alone is used. If the content is more than 50% by weight, the solvent evaporates at a high rate, and the concentration of the coating solution changes during coating, and the viscosity increases to lower the coating property, which may cause poor appearance of the coating film. In addition, there is a risk of fire. Further, the coating amount (the weight of the solid content per unit area of the film) is preferably 0.05 to 0.50 g Zm ² . If the coating amount is less than 0.05 g Zm ² , the adhesiveness becomes insufficient. If the coating amount exceeds 0.50 g Zm ² , the total light transmittance decreases, which is not preferable.

The biaxially oriented polyester film needs to have a total light transmittance of 90% or more, preferably 91% or more, and particularly preferably 92% or more. When the total light transmittance is less than 90%, the total light transmittance as a transparent conductive film is insufficient, which is not preferable. In order to make the total light transmittance of the biaxially oriented polyester film 90% or more, it is preferable not to include particles in the base film. When no particles are contained in the base film, it is preferable to include appropriate particles in the coating layer in order to improve the scratch resistance and the winding property of the film in the coating layer.

 Examples of such particles include inorganic particles such as calcium carbonate, calcium phosphate, silica, glass filler, kaolin, talc, titanium dioxide, alumina, barium sulfate, calcium fluoride, lithium fluoride, zeolite, molybdenum disulfide, and the like. Organic particles such as polymer particles, silicon resin particles and calcium oxalate can be given. Among them, silica particles are most preferable because they have a refractive index relatively close to that of the polyester resin and can easily obtain a highly transparent film.

 It is preferable that two types of particles (particle A and particle B) are contained in the coating layer of the biaxially oriented polyester film. The average particle size of the particles A is preferably from 20 to 300 nm, more preferably from 30 to 100 nm. If the average particle size of the particles A is less than 20 nm, the scratch resistance tends to deteriorate. On the other hand, when the average particle diameter of the particles A exceeds 300 nm, the total light transmittance tends to decrease.

 In the present invention, the scratch resistance can be further improved by using the particles A in combination with the particles A. The average particle size of the particles B is preferably from 300 to 100 nm, more preferably from 400 to 800 nm. If the average particle size of the particles B is less than 300 nm, the scratch resistance tends to deteriorate. On the other hand, when the average particle diameter of the particles B exceeds 1 OOOnm, the total light transmittance tends to decrease. Further, the particles B are preferably aggregated particles obtained by aggregating primary particles. It is particularly preferable that the ratio of the average particle diameter of the particles B in the aggregated state to the average particle diameter of the primary particles be 6 times or more from the viewpoint of scratch resistance.

Further, the content ratio (AZB) of the particles A and B in the coating layer should be 5 to 30 and the content of the particles B should be 0.1 to 1% by weight based on the solid content of the coating layer. Is suitable for setting the three-dimensional center plane average surface roughness (SR a) of the coating layer surface to 0.002 to 0.010, and setting the respective particle contents to be within the above range. It is necessary to. In particular, when the content of the particles B exceeds 1% by weight with respect to the resin composition of the coating layer, the total light transmittance is significantly reduced. With the resin composition of the coating layer described above Means a solid content composed of resin A, resin B, particle A, and particle B.

 Furthermore, in order to increase the total light transmittance of the biaxially oriented polyester film to 90% or more, it is necessary to remove foreign substances from the coating liquid and the base polyester film, and to prepare an unstretched sheet (particularly, It is effective to rapidly cool the surface that does not contact the chill roll.

 The filter medium for microfiltration of the coating solution preferably has a filtration particle size (initial filtration efficiency: 95%) of 25 m or less. If the filtration particle size exceeds 25 m, the removal of coarse aggregates tends to be insufficient. For this reason, coarse aggregates that could not be removed by filtration are spread as a result of stretching stress in the uniaxial stretching or biaxial stretching process after coating and drying, and are recognized as aggregates of 100 m or more. It causes the light transmittance to decrease.

 There is no particular limitation on the type of filter medium for finely filtering the coating solution as long as it has the above performance, and examples thereof include a filament type, a filter type, and a mesh type. The material of the filter medium for precision filtration of the coating liquid is not particularly limited as long as it has the above-mentioned performance and does not adversely affect the coating liquid, and examples thereof include stainless steel, polyethylene, polypropylene, and nylon.

 For the base polyester film, high-precision filtration is performed at any place where the molten polyester resin is maintained at about 280 ° C during melt extrusion in order to remove foreign substances contained in the raw polyester resin. I do. The filter medium used for the high-precision filtration of the molten polyester resin is not particularly limited. In the case of the filter medium of the sintered stainless steel, the aggregates mainly composed of Si, Ti, Sb, Ge, and Cu ( It is excellent in removing performance of catalyst (caused by contamination) and high melting point polyester, and is suitable. The filtration particle size (initial filtration efficiency: 95%) of the filter medium used for high-precision filtration of the molten polyester resin is preferably 15 m or less. If the filter particle size of the filter medium exceeds 15 m, the removal of foreign substances of 20 m or more tends to be insufficient. Productivity may be reduced by high-precision filtration of molten polyester resin using a filter medium with a filtration particle size (initial filtration efficiency: 95%) of 15 m or less, but high total light transmittance is high. It is very suitable for obtaining a biaxially oriented polyester film.

Even in the case of fine foreign matter that passes through the filter medium in the high-precision filtration, Crystallization progresses around the foreign material during the cooling process during the production of the steal sheet, which causes non-uniformity of the stretching in the stretching process, causing a minute difference in thickness and a lens state. Here, the light is refracted or scattered as if it has a lens, and when viewed with the naked eye it appears larger than the actual foreign object. This small difference in thickness can be observed as the difference between the height of the projections and the depth of the depressions, where the height of the projections is 1 m or more and the depth of the depressions adjacent to the projections is 0. If it is 5 m or more, the lens effect will cause the object with a shape of 20 m to be visually recognized as a size of 50 m or more, and even a size of 100 m or more. It may be recognized as an optical defect. In order to obtain a highly transparent film, it is desirable not to include particles for imparting lubricity in the base film.However, as the amount of added particles is small and the transparency is high, the optical properties due to fine irregularities The disadvantages tend to be sharper. Also, the surface of a thick film is less likely to be quenched than a thin film and tends to be crystallized. Therefore, it is necessary to quench the entire film when preparing an unstretched sheet. As a method of cooling the unstretched sheet, the molten resin is extruded from a die onto a rotating cooling drum onto a sheet, and the sheet-like molten material is rapidly cooled while being in close contact with the rotating cooling drum to form a sheet. Known methods can be applied. As a method for cooling the air surface (the surface opposite to the surface that comes into contact with the cooling drum) of this sheet-like material, a method of blowing a high-speed air stream to cool the sheet is effective. Next, a method for producing a biaxially oriented polyester film used as a substrate of the transparent conductive film of the present invention will be described using polyethylene terephthalate (hereinafter abbreviated as PET) as an example. is not.

 After sufficiently drying the PET resin pellets substantially containing no particles, they are supplied to an extruder, melt-extruded into a sheet at about 280 ° C, cooled and solidified to form an undrawn FET sheet. Form a film. At this time, the high-precision filtration is performed at an arbitrary place where the molten resin is kept at about 280 ° C. in order to remove foreign substances contained in the resin.

The obtained unstretched PET sheet is stretched 2.5 to 5.0 times in the longitudinal direction by a roll heated to 80 to 120 ° C to obtain a uniaxially oriented PET film. Furthermore, the end of the film is gripped with a clip, guided to a hot air zone heated to 80 to 180 ° C, and stretched 2.5 to 5.0 times in the width direction after drying. Subsequently, it is led to a heat treatment zone of 160 to 240 ° C., and heat-treated for 1 to 60 seconds to complete the crystal orientation. This heat During the treatment process, if necessary, a 1 to 12% relaxation treatment may be performed in the width direction or the longitudinal direction.

 At any stage during this step, an aqueous solution of the above-mentioned copolymerized polyester and polyurethane resin is applied to one or both sides of the PET film. The aqueous coating solution can be applied by any known method. For example, reverse roll-coat method, gravure 'coat method, kiss' coat method, roll brush method, spray coat method, air knife coat method, wire-barber coat method, pipe doctor method, impregnation coat method and curtain Coating methods and the like can be mentioned, and these methods can be performed alone or in combination.

 The step of applying the aqueous coating solution may be a normal coating step, that is, a step of coating a biaxially stretched and heat-set base PET film, but an in-line coating method of coating during the PET film manufacturing process may be used. preferable. More preferably, it is applied to the base PET film before the crystal orientation is completed.

The solid concentration in the aqueous coating solution is preferably 30% by weight or less, particularly preferably 10% by weight or less. The PET film coated with the aqueous coating solution is guided to a tenter for stretching and heat setting, where it is heated to form a stable film by a thermal crosslinking reaction, and becomes a laminated PET film. Further, when stacking another layer on the coating layer, in order to obtain good adhesion with other layers, there is a coating fabric of the PET film is 0. 05 gZm ² or more, 100 ° C, Heat treatment for 1 minute or more is required.

 The three-dimensional center plane average surface roughness (SRa) of the coating layer surface of the biaxially oriented FET film needs to be 0.002 to 0.001〃m, preferably 0.0025 to 0.008 0〃m. And 0.0030 to 0.0060 μm are particularly preferred. Smooth surfaces with SRa of less than 0.002 m are not preferred because scratch resistance deteriorates. On the other hand, when SRa exceeds 0.010 m, the total light transmittance is reduced and the transparency is deteriorated, so that it is not preferable as a substrate of the transparent conductive film.

It is preferable that the content and the ratio of the particles A and the particles B and the coating amount are within the above ranges, so that the ranges of SRa and the total light transmittance defined in the present invention are within the ranges. It is effective for achieving both scratch resistance. The biaxially oriented PET film having the coating layer obtained in this manner has excellent transparency and adhesiveness and excellent scratch resistance in a post-processing step. Therefore, it is suitable as a base film of a transparent conductive thin film as described below.

 The thickness of the biaxially oriented PET film is preferably in the range of more than 10 m and not more than 300 m, particularly preferably in the range of 70 to 260 m. When the thickness of the film is 10 m or less, the stiffness of the film tends to be insufficient, and the durability tends to be poor. On the other hand, if it exceeds 300 m, the light transmittance is undesirably high. In addition, the characteristics of the film, which is lightweight, become indispensable.

 The biaxially oriented PET film may be subjected to surface treatment such as corona discharge treatment and glow discharge treatment to the extent that the object of the present invention is not impaired.

 When a transparent conductive film using a biaxially stretched PET film as a base material is used as a transparent electrode of an EL panel, a heat treatment at 100 to 150 ° C is performed in a printing process such as circuit processing. This heat treatment may cause an increase in haze value or white appearance defects.

 The inventors of the present invention focused on the fact that the main factors of the increase in haze and the white defect after the heat treatment of the biaxially oriented PET film were the cyclic trimer, which is the main component of the oligomer, and conducted extensive studies. As a result, the content of cyclic trimer contained in the raw material PET resin and the residence time until casting in the PET film forming process have the greatest effect on the content of cyclic trimer in the film. Elucidated.

 As a result, it was found that when the content of the cyclic trimer contained in the film was set to 5000 ppm or less, more preferably 4500 ppm or less, an increase in the haze value after the heat treatment could be suppressed.

 To reduce the amount of oligomers typified by cyclic trimers, the raw PET resin is first subjected to a low-pressure treatment under a specific pressure and temperature range for a specific time in an atmosphere of an inert gas such as nitrogen. Is preferred.

The pressurizing condition is preferably higher than 1 atm and 2 atm or less, particularly preferably higher than 1 atm and 1.4 atm or less. The heating temperature is preferably from 180 ° C to 250 ° C, particularly preferably from 200 ° C to 230 ° C. In addition, processing time is more than 12 hours 3 Preferably not more than 6 hours.

 At this time, if oxygen is present in the atmosphere, problems such as coloring due to an oxidation reaction occur, and if water vapor is present, a hydrolysis reaction causes a reduction in the degree of polymerization of PET and a problem such as a reduction in film strength. I do. If the pressure in an inert gas atmosphere is lower than 1 atm, specially designed equipment is required to prevent oxygen and water vapor from entering with the outside air. On the other hand, even if the pressure in an inert gas atmosphere is higher than 2 atm, the effect of reducing oligomers does not change.

 If the temperature of the low oligomerization treatment is higher than 250 ° C, problems such as fusion, melting, and discoloration of the PET resin are likely to occur. On the other hand, when the temperature is lower than 180 ° C., the effect of reducing oligomers tends to be insufficient. If the treatment time is shorter than 12 hours, the effect of reducing oligomers tends to be insufficient. On the other hand, if the treatment time is longer than 36 hours, the effect of increasing the haze value by the heat treatment of the film does not change.

 It is preferable to use, in combination with the low oligomerization treatment of the PET resin, a deactivation treatment for reducing the catalytic activity. For example, a treatment for reducing or losing the catalytic activity may be performed by a chemical treatment such as oxidation, reduction, or hydration, or a physical treatment such as irradiation with sonic or electromagnetic waves or electromagnetic waves. Further, a chemical modification such as etherification may be applied to the alcohol terminal of PET to suppress the oligomer regeneration reaction such as a cyclic trimer. If the catalyst deactivation treatment and the regeneration suppression treatment are not performed, if the raw PET resin is re-melted during the production of the film, the oligomer is regenerated with time. Therefore, by controlling the residence time from re-melting the PET resin to extrusion and cooling to within 20 minutes, more preferably within 12 minutes, the content of the cyclic trimer in the biaxially oriented PET film is controlled. Can be suppressed to 500 ppm or less, and a film with a small increase in haze value after heating can be produced.

In addition, oligomers may segregate on the film surface due to heat setting during film formation, but by controlling the amount of oligomers on the surface to 0.5 mg / m ² or less, heating in the printing process such as circuit processing can be performed. It is possible to further reduce the increase in the haze value and the occurrence of white appearance defects due to the treatment. To the surface an oligomer amount and 0. 5 mg Zm ² or less, good to make the heat treatment temperature during the film formation below 2 3 5 ° C It is particularly preferable that the temperature be 230 ° C. or lower.

 Furthermore, in order to suppress the increase in the haze value due to the heat treatment, it is effective to provide a thin film layer made of a crosslinked resin on the surface of the transparent conductive film on which the transparent conductive layer is not formed. is there. The thin film layer made of the cross-linked resin makes it possible to block oligomers precipitated from the film by heating, and increases the haze value and the white appearance defect due to heat treatment in a printing process such as circuit processing. It will not occur. In order to block such a low molecular weight oligomer, it is necessary that the crosslinked network structure of the crosslinked resin is smaller than that of the oligomer. In order to obtain such a network structure, a crosslinked resin having many crosslinking points and a low molecular weight is preferable. That is, the thin film layer made of the cross-linked resin is made of a polyfunctional cross-linked resin having three or more functional groups, and the functional groups and Z or the functional group and the bi-functional resin or water previously added to the thin film layer are added. Formed as a result of the reaction with It is preferable that the thin film layer made of the crosslinked resin contains a polyfunctional isocyanate resin and a Z or polyfunctional epoxy resin as main polyfunctional crosslinked resin components.

 As the polyfunctional isocyanate-based resin and the polyfunctional epoxy-based resin used for the thin film 2 composed of a cross-linked resin, a resin having an initial molecular weight of 200 or less per three functional groups is preferable. More preferably, it is a resin of 150 or less, particularly preferably 100 or less. Further, a resin having a minimum value of 50 or less chemical bonds between functional groups is also preferable. The resin is more preferably 30 or less, particularly preferably 20 or less.

 If the initial molecular weight or the number of chemical bonds between the functional groups is too large, the network of the crosslinked network structure formed by the reaction tends to be too large, and the effect of suppressing whitening tends to be insufficient.

 Examples of the polyfunctional isocyanate-based resin include low-molecular or high-molecular aromatic and aliphatic diisocyanates and trivalent or higher polyisocyanates.

Examples of the trivalent or higher polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, Xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate — And trimers of these isocyanate compounds. In addition, excess amounts of these isocyanate compounds and low-molecular-weight substances such as ethylene dalicol, propylene dalicol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, etc. Examples include an active hydrogen compound or a compound containing a terminal isocyanate group, which is obtained by reacting with a high molecular weight active hydrogen compound such as polyester polyols, polyether polyols, and polyamides.

 Examples of the polyfunctional epoxy resin include diglycidyl ether of bisphenol A and its oligomer, diglycidyl ether of hydrogenated bisphenol A and its oligomer, diglycidyl orthophthalate, diglycidyl isophthalate, diglycidyl terephthalate, and the like. Glycidyl ester, diglycidyl p-oxybenzoate, diglycidyl tetrahydrophthalate, diglycidyl hexahydrophtallate, diglycidyl succinate, diglycidyl adipic acid, diglycidyl sebacate, ethylene glycol diethylene glycol Glycidyl ether, propylene dalicol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1.6-hexanediol diglycidyl ether Ter and polyalkylene glycol diglycidyl ethers, triglycidyl trimeric ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, Limethylolpropant glycidyl ether, erythritol glycidyl ether, and glycerol alkylene oxide adduct triglycidyl ether can be exemplified.

On the other hand, when the number of chemical bonds between the functional groups is 7 or less, the thin film layer formed of the cross-linked resin may be easily cracked or curled when the thin film layer is bent. Other resins may be mixed to alleviate this. The mixing amount of the other resin is preferably 70% by weight or less based on the crosslinked resin composed of the isocyanate resin and the epoxy resin. If the mixing amount exceeds 70% by weight, the network of cross-linking becomes large, and the effect of suppressing whitening during heating becomes insufficient. As the resin to be mixed with the crosslinked resin, a polyester resin, an ataryl resin, Examples include methacrylic resin, urethane acryl resin, melamine resin, silicone resin and the like. Of these, copolymerized polyester resins are most preferred. This copolymerized polyester resin is composed of a dalicol component and a dicarboxylic acid component.

 As the glycol component, ethylene glycol is most preferred. It may contain diethylene glycol, propylene glycol, butanediol, neopentyl glycol, hexanediol or 1,4-cyclohexanedimethanol.

 As the dicarboxylic acid component, terephthalic acid and isophthalic acid are most preferred. If the amount is a small amount, another dicarboxylic acid, in particular, an aromatic dicarboxylic acid such as difluorocarboxylic acid and 2,6-naphthalenedicarboxylic acid may be added for copolymerization. Further, the thickness of the thin film layer made of the crosslinked resin is preferably 0.05 to 3.0 μm in order to prevent oligomer precipitation. Particularly preferably, it is 0.1 to 2.0 μm. If the thickness of the thin film layer exceeds 3.0 m, the bending resistance becomes insufficient, and if it is less than 0.5 m, the effect of preventing oligomer precipitation becomes insufficient.

 As a method of laminating a thin film layer made of a crosslinked resin on a biaxially oriented PET film, a coating method is preferable. Further, a catalyst may be added to the coating solution containing the cross-linkable resin in order to promote the thermal cross-linking reaction. For example, inorganic substances, salts, organic substances, alkaline substances, acidic substances, metal-containing organic compounds, etc. Various chemical substances are used.

 Coating methods include air-coating method, knife coating method, □ head coating method, forward rotation roll coating method, reverse roll coating method, gravure coating method, kiss coating method, bead coating method, slit orifice A coating method, a cast coating method, or the like is used.

 Thereafter, in order to impart a crosslinked structure, after coating, energy is applied by heating, ultraviolet rays, or electron beam irradiation.

When a coating solution containing a cross-linkable resin is applied to a film, the film may be subjected to a surface treatment such as a corona discharge treatment or a glow discharge treatment in order to further increase the adhesion. The transparent conductive thin film of the present invention is not particularly limited as long as it is a material having both transparency and conductivity. Typical examples thereof include indium oxide, zinc oxide, tin oxide, indium oxide composite oxide, and silver oxide. Examples of the thin film include a zooantimony composite oxide, a zinc-aluminum composite oxide, and an indium zinc composite oxide. It is known that these compound thin films can be made into transparent conductive thin films having both transparency and conductivity when manufactured under appropriate conditions.

 As a method for forming the transparent conductive thin film, a vacuum evaporation method, a sputtering method, a CVD method, an ion plating method, a spray method, etc. are known. Can be used.

 For example, in the case of a sputtering method, a normal sputtering method using a compound, a reactive sputtering method using a metal target, or the like is used. At this time, oxygen, nitrogen, steam, or the like may be introduced as a reactive gas, or a means such as ozone addition or ion assist may be used in combination. Alternatively, a bias such as direct current, alternating current, or high frequency may be applied to the substrate. The same applies to other forming methods such as a vapor deposition method and a CVD method.

 In order to lower the surface resistivity of the transparent conductive thin film, it is generally sufficient to increase the thickness of the transparent conductive thin film, but on the contrary, there is a problem that the light transmittance is reduced. Furthermore, if the thickness of the transparent conductive thin film is too large, curling is likely to occur due to the heat treatment during the production of the EL panel, and as a result, productivity may be significantly reduced. However, the present inventors have found that increasing the thickness of the transparent conductive thin film to some extent improves the light transmittance. For example, in the case of an indium oxide composite oxide thin film, when the thickness is 80 nm or more, the light transmittance is improved. This is because the reflected light at the surface of the transparent conductive thin film and the reflected light at the interface between the biaxially oriented PET film and the transparent conductive thin film interfere with each other and cancel each other, reducing the reflected light. It is considered that the transmitted light increases due to the decrease in the light transmittance, and the light transmittance improves. That is, the refractive index of the transparent conductive thin film is N, the thickness of the transparent conductive thin film is D, and the wavelength at which light transmittance is desired to be the highest! Then

 N D = (λ / 2) x η

The thickness of the transparent conductive thin film may be adjusted so as to satisfy the following. Where η is 1 or more Is the integer above.

 For example, to obtain the highest light transmittance at 550 nm, when using an indium-tin composite oxide thin film with a refractive index of 2, the film thicknesses are 137.5 nm, 27 5.O nm, and 412 nm. . 5 nm (corresponding to n = l, 2, 3). The wavelength at which the light transmittance is highest is preferably 450 nm or more and 600 nm or less. At a wavelength lower than 450 nm, the emission luminance does not improve when used in an EL panel because it is shorter than the wavelength of visible light. Also, if the wavelength is designed to be longer than 600 nm, the transmittance at a wavelength of about 500 nm will be insufficient, and as a result, the emission luminance will not be improved when used for EL panels.

 The transmittance at the design wavelength is preferably 80% or more and 97% or less. In order to increase the light transmittance, the reflected light is designed to have a minimum value due to the interference effect as described above, so that the absorption in the transparent conductive thin film must be reduced. For that purpose, it is better to make the degree of oxidation of the transparent conductive thin film as high as possible. However, if the degree of oxidation is increased so that the light transmittance exceeds 97%, the surface resistivity becomes so high that it is not suitable as a transparent electrode of an EL panel.

 The surface resistivity of the transparent conductive film is preferably in the range of 10 to 10 Ω / b. In order to make the surface resistivity lower than 10 Ω / port, it is necessary to make the thickness of the transparent conductive thin film extremely large, so that the properties such as bending are insufficient, and the production cost is also extremely high. Become higher. On the other hand, if the surface resistivity is higher than 100 Ω / Ε], the improvement in light emission luminance when used in an EL panel becomes insufficient.

Also, if the thickness of the transparent conductive thin film is simply increased to 80 nm or more, curling is likely to occur when heat treatment is performed in a subsequent printing process. As a result, the processability deteriorates, which may lead to a decrease in productivity. Therefore, it is preferable that the amount of warpage in a size of 3 Omm x 3 Omm when the transparent conductive film is heat-treated at 150 ° C for 3 hours is 2 mm or less. In order to reduce the warpage to 2 mm or less, it is preferable that the dimensional shrinkage of the transparent conductive film be 0.2% or less after heat treatment at 150 ° C. for 3 hours. If the dimensional shrinkage after heat treatment at 150 ° C for 3 hours exceeds 0.2%, curling is likely to occur in the printing process during EL panel manufacturing. For this reason, process passability is deteriorated, and productivity tends to decrease. Heat treatment In order to reduce the dimensional change due to the process, it is preferable to heat-treat the transparent conductive film in advance or to provide a thin film layer made of the above-mentioned crosslinked resin. The step of heat-treating the transparent conductive film may be performed after the production of the biaxially oriented PET film before forming the transparent conductive thin film, or may be performed during the production of the biaxially oriented PET film. The latter is more preferable from the viewpoint of productivity.

 In order to perform a heat treatment on the biaxially oriented PET film, an in-line treatment in which a heat treatment at about 200 to 240 ° C. is performed in the heat setting treatment step in the production of the biaxially oriented PET film is preferable. If the heat setting temperature is lower than 200 ° C, the effect of reducing the dimensional shrinkage after heat treatment during post-processing is insufficient. On the other hand, at a high temperature exceeding 240 ° C., it is difficult to stably form a biaxially oriented PET film.

 In addition, a coating agent containing the above-mentioned cross-linkable resin is applied to the biaxially oriented PET film off-line, and a heat treatment is performed to dry and cure the coating agent. You may.

 In order to dry and cure the thin film layer made of the crosslinked resin and to reduce the dimensional shrinkage of the transparent conductive film, the temperature of the drying oven is preferably set to 120 to 240 ° C. If the temperature is lower than 120 ° C., the effect of reducing the dimensional shrinkage after the heat treatment is insufficient. On the other hand, at a high temperature exceeding 240 ° C., the planarity of the biaxially oriented PET film tends to decrease.

 The transparent conductive film of the present invention can suppress blackening of the transparent conductive film when used for a transparent electrode of an EL panel by laminating a dielectric thin film on the transparent conductive thin film. . The mechanism of this blackening is considered to be that the transparent conductive thin film is reduced and blackened by electron transfer due to the voltage applied to the light emitting layer when used in an EL panel. By laminating a dielectric thin film, electron transfer to the transparent conductive thin film is suppressed, and blackening is less likely to occur.

The dielectric material preferably used in the present invention includes boron oxide, magnesium oxide, aluminum oxide, silicon oxide, titanium oxide, vanadium oxide, chromium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, and copper oxide. , Zinc oxide, yttrium oxide, zirconium oxide, niobium oxide, molybdenum oxide, lead oxide, tin oxide, antimony oxide, barium oxide, hafnium oxide, thallium oxide, thallium oxide Ngustene, platinum oxide, bismuth oxide, barium titanate, lead titanate, potassium niobate, lithium niobate, lithium tantalate, lead sulfate, silicon carbide, strontium sulfate, zinc sulfide, silicon nitride, silver bromide, silver chloride These may be used alone or as a mixture of two or more.

 Among these materials, titanium oxide is preferably used. Titanium oxide has a very large non-dielectric constant of 170, and when the transparent conductive film of the present invention in which a titanium oxide thin film is laminated is used for an EL panel, an applied voltage can be efficiently applied to the light emitting layer. There is almost no decrease in light emission luminance.

 In order to form the dielectric thin film, a vacuum deposition method, a sputtering method, a CVD method, an ion plating method, a spray method, and the like are known. Depending on the type of the material and the required film thickness, an appropriate method is used. A known method can be used.

 For example, in the case of the sputtering method, a normal sputtering method using a compound, a reactive sputtering method using a metal target, or the like is used. At this time, oxygen, nitrogen, steam, or the like may be introduced as a reactive gas, or a means such as ozone addition or ion assist may be used in combination. Further, a bias such as direct current, alternating current, or high frequency may be applied to the substrate. Further, the substrate may be heated or cooled as necessary. The same applies to other production methods such as a vapor deposition method and a CVD method.

 The thickness of the dielectric thin film is preferably in the range of 1 to 300 nm. When the thickness is less than 1 nm, the effect of suppressing blackening of the transparent conductive thin film is insufficient. On the other hand, when the thickness is more than 300 nm, it is not preferable because it affects the optical design for increasing the light transmittance of the transparent conductive thin film.

 An EL panel using the transparent conductive film of the present invention is manufactured by laminating a light-emitting layer, a dielectric layer, a plane electrode layer, and an insulating layer in this order on a transparent conductive thin film of the transparent conductive film. Each layer may be formed by a dry process such as vapor deposition or sputtering, or may be formed by a printing method that is a wet coat, but a printing method is preferable from the viewpoint of manufacturing cost.

The light emitting layer is obtained by dispersing a light emitting powder in a binder resin. Since the binder resin needs to be a resin having excellent moisture-proof properties in order to protect the phosphor powder from moisture, it is preferable to use a fluoroelastomer. Fluoroelast The monomer is preferably a simple substance or a copolymer of vinylidene fluoride, propylene hexafluoride, tetrafluoroethylene, perfluoromethyl vinyl ether, or the like. Furthermore, polyester resin, acrylic resin, epoxy resin, melamine resin, methacrylic resin, urethane acrylic resin, silicone resin, etc. may be blended in order to strengthen the adhesion to the transparent conductive thin film and the dielectric layer. .

The luminescent powder preferably contains ZnS as a main component, and the emission wavelength can be selectively obtained in the visible light region by the added impurities. The impurity added, C u, Ag, C l , I, A l, Mn, P r F 3, Nd F 3, SmF 3, Eu F 3, T b F 3, Dy F 3, H o F 3 _{, E r F 3, TmF 3} , Y b F 3 is favored arbitrary choose from such.

 The emission wavelengths of these phosphor powders; the wavelengths at which the light transmittance of the IE and the transparent conductive film of the present invention used for the transparent electrode have the highest value are:

 ^ I- 50 nm ≤ λΕ ≤ 1+ 50 nm

By designing so as to satisfy the relational expression, it is possible to provide an electroluminescent panel having extremely high emission luminance. If the difference between / JE and I is larger than 50 nm, the improvement in emission luminance tends to be insufficient.

 In order to improve the moisture resistance of the phosphor powder, it is preferable to form a moisture-proof coating such as aluminum oxide, titanium oxide, silicon oxide, and magnesium oxide on the surface.

 Further, it is preferable to disperse the phosphor powder in a ratio of 0.1 to 100 g per 1 g of the binder resin of the light emitting layer. If the amount is less than 0.1 g, the light emission luminance is insufficient.

 The thickness of the light emitting layer is preferably in the range of 1 to 100 μm. If the thickness is less than 1 μm, the emission luminance is still insufficient. If the thickness is more than 100 m, printing is difficult in one process, which is not preferable from the viewpoint of productivity.

For the dielectric layer, a powder having a high dielectric constant such as titanium oxide, barium titanate, lead titanate, potassium niobate, lithium niobate, lithium tantalate is dispersed in the same fluoroelastomer as the light emitting layer. Are stacked. Preferably, the thickness of the dielectric layer is in the range of 1 to 100 m. At a thickness of less than 1 m from the back electrode The leakage current to the light emitting layer increases, and the light emission luminance decreases. If it is thicker than Ι Ο ί / m, printing is difficult in one process, which is not preferable from the viewpoint of productivity.

 The back electrode is printed with polyester resin and Z or silver powder dispersed in polyester resin. The thickness of the printing layer is preferably in the range of 1 to 100 m. If the thickness is less than 1 m, the surface resistivity of the back electrode becomes too high, and the emission luminance is also insufficient.If the thickness is more than 100 i / m, printing is difficult in a single step, and productivity is reduced. Not desirable from a viewpoint. The surface resistivity of the back electrode is preferably from 0.1 to 500 Ω / υ. In order to make it less than 0.1 Ω / port, the thickness of the back electrode must be considerably increased, which is not preferable from the viewpoint of productivity. On the other hand, when the surface resistivity is higher than 500 Ω / Ε], the applied voltage cannot be efficiently applied to the light emitting layer, and the light emission luminance decreases.

 It is preferable that the insulating layer is mainly composed of a polyester resin, an acrylic resin, an epoxy resin, a melamine resin, a methacryl resin, a urethane acrylic resin, a silicone resin or the like, and is printed in a range of 1 to 100 m. When the thickness is less than 1 m, the insulating effect is insufficient. When the thickness is more than 100 m, printing is difficult in one process, which is not preferable in terms of productivity.

 Further, in the present invention, a hard coat treatment layer may be provided on the surface of the transparent conductive film on which the transparent conductive thin film is not formed, in order to prevent abrasion or the like generated in the process of manufacturing an EL panel. An irregularity treatment layer may be provided to suppress the generation of Newton rings when the LCD is in close contact with the LCD, and an antireflection treatment layer may be provided to further increase the light transmittance of the transparent conductive film.

The hard coat treatment is a cross-linkable resin made of a single or mixed curable resin such as polyester resin, urethane resin, acryl resin, melamine resin, epoxy resin, silicon resin, polyimide resin. A cured resin layer is preferred. The thickness of the hard coat treatment layer is preferably in the range of 3 to 50 / m, particularly preferably in the range of 4 to 30 μm. If the thickness is less than 3 m, the function of the hard coat treatment will not be sufficiently exhibited. On the other hand, in order to make the thickness more than 50 m, the rate at which the coating liquid containing the curable resin is applied to the transparent conductive film must be significantly reduced, which is not preferable in terms of productivity. As a method of depositing the hard coat treatment layer, a coating solution containing the above-mentioned curable resin is applied to a surface of the transparent conductive film opposite to the surface on which the transparent conductive thin film is provided, by a Daravia method, a reverse method, After coating the transparent conductive film with a die method or the like, it is cured by applying energy such as heat, ultraviolet rays, and electron beams.

The unevenness-treated layer is formed by coating a curable resin, drying and then forming an unevenness on the surface of the coating layer using an embossing roll, embossed film, or the like, and then curing the applied layer by applying energy such as heat, ultraviolet rays, or an electron beam. As the curable resin, a polyester resin, a urethane resin, an acrylic resin, a melamine resin, an epoxy resin, a silicone resin, a polyimide resin, or a mixture thereof is preferable. Alternatively, an inorganic or Z and an organic filler may be mixed in the resin. In the antireflection treatment layer, it is preferable that a material having a refractive index different from that of the biaxially oriented PET film be a single layer or a laminate of two or more layers. In the case of a single-layer structure, it is preferable to use a material having a smaller refractive index than the biaxially oriented PET film. In the case of a multilayer structure of two or more layers, a material having a higher refractive index than the biaxially oriented PET film is used for the layer adjacent to the biaxially oriented PET film, and a smaller It is preferable to select a material having a refractive index. The material constituting such an anti-reflection treatment 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 , NaAlF ₄ , S i 〇 _2, ThF _4, Z R_〇 _2, Nd ₂ 0 _3, S N_〇 _2, T I_〇 _2, C E_〇 _2, Zn S, preferably used dielectrics such as I n ₂ 〇 _3, .

 The method of laminating the anti-reflection treatment layer may be a dry coating process such as a vacuum deposition method, a sputtering method, a CVD method, an ion plating method, or a wet coating process such as a gravure method, a reverse method, or a die method. Good.

 Further, prior to lamination of the hard coat treatment layer, the unevenness treatment layer, and the anti-reflection treatment layer, corona discharge treatment, plasma treatment, sputter etching treatment, electron beam irradiation treatment, ultraviolet irradiation treatment, primer treatment, A known treatment such as an easy adhesion treatment may be performed.

The transparent conductive film of the present invention is particularly suitable for an electroluminescent panel. However, it can also be used as a touch panel member. The touch panel is formed by disposing a pair of panel plates having a transparent conductive thin film via a spacer so that the transparent conductive thin films face each other. When a character is input with the pen from the transparent conductive film side, the touch panel touches the opposite transparent conductive thin films due to the pressure from the pen and turns on electrically, and the pen touches the touch panel. This is to detect the position. By using the transparent conductive film of the present invention for one or both of the pair of panel plates having the transparent conductive thin film, it is possible to produce a touch panel having high light transmittance and less appearance defects due to heat treatment. . Example of embodiment

 Next, the present invention will be described in detail with reference to examples. However, the present invention is not limited to the following examples unless departing from the gist thereof. In the following examples and comparative examples, the measurement methods used for evaluating each characteristic are as follows.

 (1) Intrinsic viscosity of polyester

 Polyester was dissolved in a mixed solvent of 60% by weight of phenol and 40% by weight of 1,1,2,2-tetracloane, and the solid content was substantially filtered, followed by measurement at 30 ° C.

 (2) Polyester cyclic trimer content

 Dissolve the sample in a mixture of hexafluoroisopropanol and chloroform, and dilute with chloroform. To this is added methanol to precipitate a polymer, which is then filtered. The filtrate was evaporated to dryness, made up to a constant volume with dimethylformamide, and the cyclic trimer composed of ethylene terephthalate units was quantified by liquid chromatography.

 (3) Adhesiveness

Apply a hard coat agent (Seika Beam EXF01 (B), manufactured by Dainichi Seika Co., Ltd.) to the coated surface of the biaxially oriented polyester film using a # 8 wire bar, and dry at 70 ° C for 1 minute to remove the solvent. A hard coat layer having a thickness of 3 m was formed using a high-pressure mercury lamp under the conditions of 200 mJZcm ² , irradiation distance of 15 cm and running speed of 5 mZ. The adhesiveness of the obtained film was determined by a test method according to 8.5.1 of JIS-K5400. Specifically, 100 square cuts that penetrated the easy-adhesion layer and reached the base film were made using a cutter guide with a gap of 2 mm. Next, a cellophane adhesive tape (Nichiban No. 405; 24 mm width) was attached to the cut-like surface of the grid, rubbed with an eraser and completely adhered, and then peeled off vertically to visually determine the adhesiveness from the following formula. Was.

 Adhesion (%) = (1 peeled area Z evaluation area) X 100

 (4) Scratch resistance

A 1000 mm wide slit film of the transparent conductive film, on which the transparent conductive thin film is not laminated, is coated with a hard chrome-plated free roll with a diameter of 220 mm and a rotation resistance of lkg (surface roughness Ra: 100 nm). The running conditions at this time were a running speed of 10 mZ, a winding angle of 60 °, and a running tension of 10 kg. The scratches that entered the film surface by this treatment were deposited with platinum and observed with a microscope. The number of width 3 or more and a length more than 500 wound area 1 m ² counts or Ah, was determined according to the following criteria.

 ◎: less than 10

 〇: 10 or more and less than 20 (practically usable)

 ： 20 or more

 (5) Total light transmittance, haze value

 Based on JIS-K7105, total light transmittance and haze value were measured using a haze meter-1 (NDH-1001 DP manufactured by Nippon Denshoku Industries Co., Ltd.).

 (6) 3D center plane average surface roughness (SRa)

 Using a stylus type three-dimensional surface roughness meter (Kosaka Laboratories, ET-30HK) and a three-dimensional roughness analyzer (Kosaka Laboratories, SPA-11), the three-dimensional surface of the film coating layer is measured. The center plane average surface roughness (SRa) was measured. The measurement conditions are as follows.

1) Probe tip radius: 2 m, 2) Probe load: 20 mg, 3) Cut-off value: 80 m, 4) Measurement length in X direction: lmm, 5) Feed speed in X direction: 100 seconds, 6 ) Sample pitch in X direction: 0.4 m, 7) Feed pitch in Y direction: 2 、 m, 8) Number of lines in Y direction: 100, 9) Magnification in Z direction: 50,000 times (7) Heat shrinkage at 150 ° C

 Draw a circle with a diameter of 30 mm around the intersection of the diagonal lines of the film cut into a square with a side of 5 Omm and place it in a hot-air dryer heated to 150 ± 3 ° C without load and at a constant temperature for 2 hours Or left for 3 hours. Then, remove the film, leave it on a flat glass plate at room temperature for 30 minutes, read the dimensional change with a digitizer, and calculate the maximum shrinkage position B (mm) through the intersection of the diagonal lines using the following formula. I did. The measurement in the above procedure was performed three times, and the average value was used.

 Heat shrinkage at 150 ° C (%) = (50—B) / 50 100

 (8) Surface resistivity

 Measured by the four-terminal method according to JIS-K-7194. As a measuring device, Lotest AMCP-T400 manufactured by Mitsubishi Yuka Co., Ltd. was used.

 (9) Warpage due to heat treatment at 150 ° C for 3 hours

 3 Ommx 30 mm size film is heat-treated at 150 ± 3 ° C for 3 hours, left on a flat glass plate at room temperature for 30 minutes, and the amount of film warpage from the glass plate is cut in 0.1 mm increments with calipers. Measure with The measurement was performed at the four corners of the film, and the maximum value was used. The unit is mm.

 (10) Maximum light transmittance and its wavelength based on spectral light transmittance measurement

 Using a spectrophotometer (manufactured by Hitachi, Ltd .: U-3500), the light transmittance at a wavelength of 300 to 800 nm was measured, and the maximum light transmittance within this range and its wavelength were measured.

 (1 1) EL panel emission brightness

 A sine wave of 100 Vrms and 40 OHz was applied between the transparent conductive thin film and the back electrode, and the luminance of this panel was measured using a colorimeter (MINOLTA: CS-100).

 (12) EL panel lifetime

 With the EL panel emitting light, leave it in a constant temperature / humidity bath controlled at a temperature of 50 ° C and a humidity of 90% RH. The emission time until the black spot with a diameter of 1 mm or more occurs is the lifetime (Hr). And

 (13) Print shift of EL panel

Measure the printing deviation of the EL panel with a vernier caliper in increments of 0.1 mm, and judge according to the following criteria. Was. 〇 is a practically usable level. Further, X may cause a short circuit between the upper and lower electrodes, and cannot be used for practical use.

 〇: less than 0.3 mm

 : 0.3 mm or more

 (14) Inspection of appearance defect of EL panel

 The whitening of the transparent conductive film surface was visually observed with the EL panel turned on and off, and judged according to the following criteria.

 〇: No whitening is observed even when the EL panel is lit

 △: Whitening is observed when the EL panel is lit

 : Whitening is observed even when the EL panel is not lit.

 (1) Adjustment of coating liquid

 The coating solution used in the present invention was prepared according to the following method. 95 parts by weight of dimethyl terephthalate, 95 parts by weight of dimethyl isophthalate, 35 parts by weight of ethylene glycol, 145 parts by weight of neopentyl glycol, 0.1 part by weight of zinc acetate and 0.1 part by weight of antimony trioxide in a reaction vessel The mixture was charged and an ester exchange reaction was performed at 180 ° C. for 3 hours.

 Next, 6.0 parts by weight of 5-sodium sulfoisophthalic acid was added, and the esterification reaction was performed at 24 CTC for 1 hour, and then at 250 ° C under reduced pressure (10 to 0.2 mm Hg) for 2 hours. A polycondensation reaction was performed to obtain a polyester resin having a molecular weight of 19,500 and a softening point of 60 ° C.

6.7 parts by weight of the obtained 30% by weight aqueous dispersion of the polyester resin (A), and 20 parts by weight of the self-crosslinkable polyurethane resin (B) containing an isocyanate group, which was opened with sodium bisulfite. % Aqueous solution (manufactured by Daiichi Kogyo Seiyaku Co., Ltd .: trade name Elastron H-3), 40 parts by weight, Elastron catalyst (manufactured by Daiichi Kogyo Seiyaku; trade name: Cat 64) 0.5 part by weight, water 44.3 Parts by weight, and 5 parts by weight of isopropyl alcohol, and 0.6 parts by weight of a 10% by weight aqueous solution of an anionic surfactant. Particle A (Nissan Chemical Industries, Ltd .: Snowtex II L, average particle size 40) nm) 2 1.8 parts by weight of a 0% by weight aqueous dispersion, and 1.1 parts by weight of a 4% by weight aqueous dispersion of particles B (manufactured by Nippon Aerosil Co., Ltd., Aerozil 0X50, average particle diameter 500 nm, average primary particle diameter 40 nm). A coating solution was prepared by adding parts by weight.

 (2) Film formation

 Particle-free polyethylene terephthalate (PET) resin pellets are heat-treated at 220 ° C for 24 hours under a nitrogen atmosphere at 1.1 atm, containing 0.64 dl Zg of intrinsic viscosity and containing cyclic trimer PET resin pellets with a volume of 3000 ppm were obtained. This pellet is used as a raw material resin for PET film, re-melted at 265 ° C, extruded from a slit die with a residence time of 6 minutes, contacted with a roll at 30 ° C, cooled and solidified, and unstretched film with a thickness of 1750 m I got At this time, a stainless sintered filter medium with a filter particle size (initial filtration efficiency 95%) of 15 m was used as a filter medium for removing foreign substances from the molten PET resin.

 Next, the unstretched film is heated to 100 ° C. by a heated roll group and an infrared heater, and then stretched 3.5 times in the longitudinal direction by a roll group having a peripheral speed difference to be uniaxially oriented. PET film was obtained.

Next, the coating solution was subjected to microfiltration with a filter material made of a polypropylene having a filtration particle size (initial filtration efficiency: 95%) of 25 m, applied to one surface of a uniaxially oriented FET film by a reverse roll method, and dried. At this time, the content ratio of the particles A and the particles B was 8, and the content of the particles B was 0.42% by weight based on the resin composition of the coating layer. The coated amount of the obtained film after drying was 0.10 g / m ² . After the application, the end of the film was gripped with a clip and guided to a hot air zone heated to 130 ° C. After drying, the film was stretched 4.0 times in the width direction, and then heat-set at 230 ° C. A biaxially oriented PET film having a coating layer on one side with a thickness of 188 m was obtained.

(3) Transparent conductive thin film formation

 A transparent conductive thin film made of indium tin oxide was formed on the non-coated side of the biaxially oriented PET film having a coating layer on one side by the following method.

DC power of ² WZcm ² was applied using an indium alloy containing 10% by weight of tin as a target (manufactured by Mitsui Kinzoku Mining Co., Ltd.). Further, eight 1 "to 1303 Ji. 111, 〇 ₂ 703 0 Ji 171 flow, under an atmosphere of 0. 4 P a, DC magnetron sputtering The film was formed by a ring method. However, instead of normal DC, a pulse of +20 V and a width of 5 s was applied at a period of 50 kHz to prevent arc discharge. Sputtering was performed while cooling the film with a cooling roll at 110 ° C. In addition, plasma emission spectroscopy was performed to control the film thickness accurately, and the intensity of 452 nm, which is the emission of indium, was constantly monitored. Since the luminous intensity is proportional to the deposition rate of the Indymoods composite oxide thin film, the luminous intensity was fed back to the film feed speed to control the film thickness. Also, the oxygen partial pressure of the atmosphere is constantly monitored by a sputter process monitor 1 (SPM200 manufactured by Hakuto Co., Ltd.), and the flow rate of the oxygen gas is adjusted so that the degree of oxidation in the thin-film tin oxide composite oxide film becomes constant. And fed back to the DC power supply. As described above, a transparent conductive thin film made of indium-tin tin oxide was deposited to obtain a transparent conductive film.

 (4) EL panel fabrication

 A light emitting layer for assembling an EL panel was prepared as follows.

 Dissolve 20 g of fluorine elastomer (Daikin Industries, Ltd .: Daiel) in 100 g of methyl ethyl ketone, and add 200 g of zinc sulfide phosphor powder

(Capsule type # 30, manufactured by OSRAM Sylvania) was dispersed. The emission wavelength of this phosphor powder is 520 nm. This was screen-printed on a transparent conductive thin film of a transparent conductive film using a 200-mesh printing plate. Thereafter, drying was performed at 150 ° C for 60 minutes. The thickness after drying was 30. At this time, the electrode extraction portion of the transparent conductive thin film was left uncoated.

 Further, a paste (barrier titanate FEL-615, manufactured by Fujikura Kasei Co., Ltd.) dispersed in a fluoroelastomer as a dielectric layer material is used, and a 200-mesh printing plate is used to form a paste on the light emitting layer. Screen printed. Thereafter, drying was performed at 150 ° C for 60 minutes. The thickness after drying was 30 m. Further, as a back electrode, a carbon paste (DY-152H-30, manufactured by Toyobo Co., Ltd.) was screen-printed on the dielectric layer using a 250-mesh printing plate. Thereafter, drying was performed at 150 ° C for 30 minutes. The thickness after drying was 20 m. Also, as an insulating layer, resist

(Fujikura Kasei Co., Ltd .: Dotaitai XB-101G) was screen-printed on the back electrode layer using a 200-mesh printing plate. Then dry at 150 ° C for 30 minutes Was. The thickness after drying was 20 m. As described above, an EL panel having a size of 5 cm × 10 cm was assembled. Example 2

 In preparing the coating liquid, the same method as in Example 1 was performed except that the content ratio of the particles A and the particles B was 20 and the content of the particles B was 0.17% by weight based on the resin composition of the coating layer. A biaxially oriented PET film having a coating layer on one side was obtained by the method. The addition amounts of water and isopropyl alcohol were adjusted while keeping the addition amount ratio constant so that the solid concentration in the coating solution was the same as in Example 1. Further, a transparent conductive thin film was deposited in the same manner as in Example 1 to obtain a transparent conductive film. An EL panel was assembled in the same manner as in Example 1. Example 3

 A biaxially oriented PET film having a coating layer on one side was obtained in the same manner as in Example 1 except that the residence time was 12 minutes. Further, a transparent conductive thin film layer was provided in the same manner as in Example 1 to obtain a transparent conductive film. An EL panel was assembled in the same manner as in Example 1. Example 4

 1. Instead of PET resin pellets heat-treated at 220 ° C for 24 hours under a nitrogen atmosphere at 1 atm, FET resin pellets dried under reduced pressure (l To rr) at 135 ° C for 6 hours were used. Except for this, a biaxially oriented PET film having a coating layer on one side was obtained in the same manner as in Example 1.

 (Preparation of cross-linked resin coating liquid)

A trifunctional isocyanate-based resin (manufactured by Nippon Polyurethane Industry Co., Ltd .: Coroneto L) was used, and dibutyltin dilaurate (manufactured by Kyodo Yakuhin Co., Ltd .: S-1260) was used as a catalyst for crosslinking. These were dissolved in a mixed solvent composed of methyl ethyl ketone, toluene and cyclohexanone at the ratios shown in Table 1 to prepare a coating solution having a solid content of 5% by weight. (Formation of thin film layer made of cross-linked resin)

The coating surface of the biaxially stretched FET film produced in the same manner as in Example 1 was coated by the reverse coating method using the above coating solution. At this time, the gap between the metalling roll and the applicator roll was set to 50 μm, and heated at 180 ° C. for 30 seconds, followed by drying and crosslinking. The line speed at this time was set to 2 O mZ. The thickness of the formed thin film layer of the crosslinked resin was 0.5 μm.

 A transparent conductive thin film was formed on the surface of the biaxially stretched PET film on which no thin film layer made of a crosslinked resin was formed, in the same manner as in Example 1, to obtain a transparent conductive film. In addition, an EL panel was produced in the same manner as in Example 1 using this transparent conductive film. Example 5

 Using trifunctional epoxy resin (Dainippon Ink & Chemicals, Inc .: CR-5L), coating solutions having a solid content concentration of 5% by weight as shown in Table 1 were prepared. This coating solution was applied in the same manner as in Example 4. The thickness of the thin film layer made of a crosslinked resin was set to 0.5 m. A transparent conductive thin film was formed on the surface of the biaxially stretched PET film on which no thin film layer made of a crosslinked resin was formed, in the same manner as in Example 1, to obtain a transparent conductive film. Further, an EL panel was produced in the same manner as in Example 1 using this transparent conductive film. Example 6

Using a trifunctional isocyanate-based resin (manufactured by Nippon Polyurethane Industry Co., Ltd .: Coronate L) and a copolymerized polyester resin (manufactured by Toyobo Co., Ltd .: Byron 200), the solid content concentration as shown in Table 1 was 5% by weight. Was prepared. This coating solution was applied in the same manner as in Example 4. The thickness of the thin film layer made of cross-linked resin was 0.5 m. A transparent conductive thin film was formed on the surface of the biaxially stretched PET film on which the thin film layer made of the crosslinked resin was not formed in the same manner as in Example 1 to obtain a transparent conductive film. Further, an EL panel was manufactured in the same manner as in Example 1 using this transparent conductive film. Example 7

A thin film layer made of a crosslinked resin produced in the same manner as in Example 4 Z biaxially stretched PET film (coating layer Z base PET layer) A dielectric material is formed on the transparent conductive thin film of the laminate made of the transparent conductive thin film. A titanium oxide thin film was formed as a thin film. At this time, titanium was used as a target, and the applied power was 8 W / cm ² . Further, Ar and 500 sc cm, 〇 ₂ flushed 80 sc cm, under an atmosphere of 0. 4 Pa, and a film was formed by a DC magnetron emissions sputtering. However, instead of normal DC, a +20 V pulse of 5 s width was applied at a period of 100 kHz to prevent arc discharge. The film was wound around a cooling roll at 110 ° C, and sputtering was performed while cooling the film. At this time, the thickness of the titanium oxide was 10 nm.

 Further, using this transparent conductive film, an EL panel was assembled in the same manner as in Example 1. Comparative Example 1

In the preparation of the coating solution, the same method as in Example 1 was used except that aggregated silica particles having an average particle size of 1400 nm (Fuji Silicia: Silica 310) were used as the particles A. An axially oriented PET film was obtained. At this time, the content ratio of the particles A and the particles B was 8, and the content of the particles B was 0.42% by weight based on the solid content of the coating layer. Incidentally, the solid content concentration in the coating liquid so that in the same manner as in Example 1, Mizu及Beauty isopropyl alcohol amount to a constant amount ratio therebetween while adjusted _c further transparent in the same manner as in Example 1 A conductive thin film was formed to obtain a transparent conductive film. Using this transparent conductive film, an EL panel was produced in the same manner as in Example 1. Comparative Example 2

In Example 1, low-pressure drying (1 To rr) treatment at 135 ° C for 6 hours without using FET resin that had been treated with low temperature (1.1 heat treatment at 220 ° C for 24 hours under a nitrogen stream). Except for using the PET resin subjected to A biaxially oriented PET film having a coating layer on the surface was obtained. Further, a transparent conductive thin film was formed in the same manner as in Example 1 to obtain a transparent conductive film. An electroluminescent panel was produced in the same manner as in Example 1 using this transparent conductive film. Comparative Example 3

 A biaxially oriented PET film having a coating layer on one side was obtained in the same manner as in Example 1 except that the residence time was 25 minutes. Further, a transparent conductive thin film was formed in the same manner as in Example 1 to obtain a transparent conductive film. Using this transparent conductive film, an EL panel was produced in the same manner as in Example 1. Comparative Example 4

 A transparent conductive film was produced in the same manner as in Example 6, except that the ratio of the trifunctional isocyanate-based resin and the copolymerized polyester resin was changed to the ratio shown in Table 1. Further, an EL panel was produced in the same manner as in Example 1 using this transparent conductive film. Table 2 shows the properties of the biaxially stretched PET film for the above Examples and Comparative Examples. Tables 3 and 4 show the properties of the transparent conductive film. Further, Table 5 shows the characteristics of EL panels manufactured using these transparent conductive films. The invention's effect

The transparent conductive film of the present invention uses a highly transparent biaxially oriented polyester film having a coating layer on at least one side as a base material, and has a small change in transparency even after heat treatment during post-processing. Therefore, when used for EL panels, there are very few external defects such as whitening and excellent visibility. Further, by making the warp value when the transparent conductive film of the present invention is subjected to heat treatment at 150 ° C. for 3 hours to 2 mm or less, printing deviation during EL panel production is extremely reduced. Furthermore, the light transmittance of the transparent conductive film has a maximum value in the visible light region of 450 to 600 nm, the light transmittance at this wavelength is set to 80 to 97%, and furthermore, the surface is broken. By lowering the rate, light emission An EL panel with excellent brightness can be obtained,

table 1

Table 2 Adhesion resistance Anti-scratch All-ray haze SRa Annular 3 level Ratuna Transmittance value (m) Body content (%) (%) (ppm) Example 1 99 ◎ 92.6 1.0 0.00356 3300 Example 2 100 〇 91.7 0.9 0.00399 3300 Example 3 99 ◎ 92.6 1.0 0.00356 4500 Example 4 99 ◎ 92.6 1.0 0.00356 10000 Example 5 99 ◎ 92.6 1.0 0.00356 10000 Example 6 99 ◎ 92.6 1.0 0.00356 10000 Example 7 99 ◎ 92.6 1.0 0.00356 10000 Comparative Example 1 99 ◎ 86.4 5.2 0.0165 3300 Comparative Example 2 99 ◎ 92.6 1.0 0.00356 10000 Comparative Example 3 99 ◎ 92.6 1.0 0.00356 8000 Comparative Example 4 99 ◎ 92.6 1.0 0.00356 10000 Table 3

Table 4 Haze value increase after heat treatment Heat shrinkage Warpage

150 ° C 2Hr 150 ° Cx3Hr [150 ° C 3Hr] [150 ° Cx3Hr] (%) (%) (%) (mm; Example 1 0.3 0.8 0.68 0.0 Example 2 0.3 0.8 0.68 0.0 Example 3 0.5 1.2 0.68 0.0 Example 4 0.1 0.3 0.10 0.1 Example 5 0.3 0.8 0.12 0.1 Example 6 0.5 1.2 0.15 0.1 Example 7 0.3 0.8 0.10 0.1 Comparative example 1 0.4 0.8 0.68 0.0 Comparative example 2 13.2 15.2 0.68 0.0 Comparative example 3 12.5 13.8 0.68 0.0 Comparative Example 4 0.9 2.5 0.15 0.1 Table 5

EL panel EL panel EL panel EL panel E

95 ノ¹ fe J yy ιι ^^ ττΒ M Dimensional Question | JJE HT ^J I WfflJl

(Cd / m ² ) (hour)

Example 1 45 100 〇 〇 Example 2 45 100 〇 〇 Example 3 45 100 〇 〇 Example 4 75 210 〇 実 施 Example 5 75 210 〇 実 施 Example 6 75 220 〇 〇 Example 7 75 700 〇 比較 Compare Example 1 31 80 〇 〇 Comparative example 2 45 90 〇 X Comparative example 3 45 100 〇 X Comparative example 4 75 120 〇 Δ

Claims

The scope of the claims

1. A transparent conductive film in which a transparent conductive thin film is laminated on one side of a biaxially oriented polyester film, wherein a coating layer is formed on at least one side of the biaxially oriented polyester film, and the total light transmittance is 90%. The three-dimensional center plane average surface roughness (SR a) of the coating layer surface is 0.02 to 0.010 m, and the transparent conductive film is 3 ° C at 150 ° C. A transparent conductive film, wherein a haze value before and after heat treatment after heat treatment for 2.0 hours is 2.0% or less.

2. The transparent conductive film according to claim 1, wherein when the transparent conductive film is heat-treated at 150 ° C. for 2 hours, a haze value before and after the heat treatment is 0.5% or less. Film.

3. The transparent conductive film according to claim 1, wherein the total light transmittance of the transparent conductive film is 84% or more.

4. The transparent conductive film according to claim 1, wherein the resin composition constituting the coating layer contains a copolymerized polyester resin and a polyurethane resin.

5. The transparent conductive film according to claim 1, wherein the resin composition constituting the coating layer contains a copolymerized polyester resin containing a branched dalicol component and a resin containing a block-type isocyanate group.

6. The transparent conductive film according to claim 1, wherein the content of the cyclic trimer in the biaxially stretched polyester film is 50,000 pPm or less.

7. The polyester film according to claim 1, wherein a thin film layer made of a cross-linkable resin is provided on a surface of the transparent conductive film on which the transparent conductive thin film is not formed.

8. A transparent conductive film, wherein the cross-linkable resin according to claim 7 comprises an isocyanate-based resin and / or an epoxy-based resin.

9. The transparent conductive film according to claim 1, wherein the thickness of the transparent conductive thin film is 80 nm or more.

10. A transparent conductive film, wherein the transparent conductive film according to claim 9 has a warpage of 2 mm or less in a size of 3 Omm x 3 Omm when heated at 150 ° C for 3 hours.

11. The transparent conductive film according to claim 9, wherein a heat shrinkage ratio when heat-treated at 150 ° C. for 3 hours is 1.0% or less.

12. The transparent conductive film according to claim 9, wherein the transparent conductive film has a maximum light transmittance in a wavelength range of 450 to 600 nm, and a maximum value of brackets is 80 to 97%. Film.

13. The transparent conductive film according to claim 12, wherein the surface resistivity is 10 to 100 ΩΖΕ].

14. The transparent conductive film according to claim 12, wherein a dielectric thin film is laminated on the transparent conductive thin film.

15. An electroluminescent panel, characterized in that a light-emitting layer, a dielectric layer, a back electrode layer, and an insulating layer are laminated in this order on the transparent conductive thin film of the transparent conductive film according to claim 1.

16. An element characterized in that the emission wavelength of the light-emitting layer / 1E and the wavelength i I at which the light transmittance of the transparent conductive film according to claim 12 has a maximum value satisfy the following expression. Control luminescence panel.

 λ I-50 nm ≤ ≤ ^ 1+ 50 nm