KR20170086612A - Transparent conductive film, transparent conductive film laminate, and touch panel - Google Patents

Abstract

A transparent conductive film laminate and a touch panel capable of suppressing the generation of curl even after the heating process and ensuring the subsequent process yield in a transparent conductive film laminate in which a thin conductive glass substrate is laminated on a transparent conductive film, .
The transparent conductive film 10 according to the present invention is characterized in that a first cured resin layer 2 and a transparent conductive film 3 are formed in this order on one side of the transparent resin film 1, A transparent conductive film (10) having a second cured resin layer (4) formed on the other surface side of the transparent conductive film (1), wherein the transparent resin film (1) is made of an amorphous resin, (A - B) between the average curl value A at the four corner portions and the curl value B at the center portion after heating at 130 占 폚 for 90 minutes with the transparent conductive film 3 as the lower surface was cut to 50 cm and the transparent conductive film Film (10).

Description

TECHNICAL FIELD [0001] The present invention relates to a transparent conductive film, a transparent conductive film laminate, and a touch panel,

TECHNICAL FIELD The present invention relates to a transparent conductive film, a transparent conductive film laminate, and a touch panel, and is a technique particularly useful for controlling generation of curl.

BACKGROUND ART [0002] Conventionally, as substrates for liquid crystal displays, organic electroluminescence displays, touch panels and the like, glass substrates have been used. In recent years, along with the thinness of displays, attention has been paid to thinning of glass substrates having excellent transparency, surface smoothness, heat resistance, and the like.

On the other hand, in a capacitive touch panel configuration, polyethylene terephthalate (PET) is widely used as a base film of a transparent conductive film. However, since the PET film is formed by stretching and has a high retardation, it is difficult to use the PET film as a base of a polarizing plate. Therefore, in Patent Document 1, a transparent conductive film using a cycloolefin-based resin, which is an amorphous resin, has been proposed as a low-phase-difference base film.

Patent Document 2 discloses a transparent conductive film in which a transparent conductive film is formed on polycarbonate or a non-crystalline polyolefin film as a? / 4 retardation film usable under a polarizing plate such as a liquid crystal display. A laminate obtained by laminating on a glass substrate and a liquid crystal display device in which a touch panel function is given to the entire surface of the flexible cover glass is proposed.

In the case where the transparent conductive film is crystallized after the transparent conductive film is laminated to a thin glass substrate to form a transparent conductive film laminate or metal wiring for frame wiring is performed, There are many cases of passing through. In such a case, since the glass substrate is thin, it is easily affected by heating, and the heat shrinkage rate differs between the resin and the glass, so that the laminate is curled and can not be transported to the next step, It is difficult to carry out the production in a stable and continuous manner.

Japanese Laid-Open Patent Publication No. 2013-114344 Japanese Patent Application Laid-Open No. 2014-137427

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a transparent conductive film laminate which is a laminate of a transparent conductive film and a thin glass substrate laminated thereon, which can suppress the generation of curl even after the heating process, A transparent conductive film laminate, and a touch panel.

The present inventors have intensively studied in order to solve the above problems and found that when the transparent conductive film laminate is curled largely in the concave direction when the transparent conductive film is raised, when the transparent conductive film of the transparent conductive film is downward, The present invention has been accomplished on the basis of these findings.

That is, in the transparent conductive film of the present invention, the first cured resin layer and the transparent conductive film are formed in this order on one side of the transparent resin film, and the second cured resin layer is formed on the other side of the transparent resin film Wherein the transparent conductive film is made of an amorphous resin and the transparent conductive film is cut to 50 cm x 50 cm and the transparent conductive film is heated to 130 deg. And the difference (A - B) between the curled value A and the curled value B at the center is 5 mm or more. The various physical property values in the present invention are values measured by a method adopted in the examples and the like unless otherwise specified.

The non-qualitative resin forming the transparent resin film is usually formed by an extrusion process or a cast film formation process, and residual stress remains, and shrinkage stress is generated by heating. On the other hand, the thin glass has a small shrinkage stress overwhelmingly when heated at about 130 캜. Therefore, in the transparent conductive film laminate in which the transparent conductive film is laminated with the parchment paper, when the transparent conductive film is heated up, curling occurs in the concave direction. In the transparent conductive film, curling due to heating occurs because the transparent conductive film as the inorganic material and the transparent resin film as the organic material have different heat shrinkage ratios and linear expansion coefficients. Therefore, in the present invention, if the transparent conductive film of the transparent conductive film is made to be curled in the concave direction in advance, the curling after the heating process can be made very small in the transparent conductive film laminate to which the parchment- I found out. That is, the difference (A - B) between the average curl value A at the four corner portions and the curl value B at the center portion after heating at 130 DEG C for 90 minutes with the transparent conductive film cut to 50 cm x 50 cm was 5 Mm, it is possible to cancel out the shrinkage force generated in the laminated body laminated on the conventional glass substrate and the shrinkage force generated in the transparent conductive film, so that in the transparent conductive film laminate after lamination with the thin glass substrate, So that the curl afterward can be made very small. This makes it possible to suppress the curling of the transparent conductive film after heating by crystallization of the transparent conductive film, metal wiring processing, etc., so that stable and continuous machining and transportation can be achieved, and the subsequent process yield can be ensured.

In the transparent conductive film of the present invention, the thickness of the first cured resin layer and the thickness of the second cured resin layer are both 2 mu m or less, and the thickness of the second cured resin layer is It is preferable that it is equal to or thinner than the thickness. If the thickness of the first cured resin layer and the thickness of the second cured resin layer are as thin as described above, the influence of the shrinkage force caused by the cured resin layer can be reduced, and the transparent resin film is easily affected by heating , Curl becomes easier to occur. When the thickness of the second cured resin layer is made equal to or smaller than the thickness of the first cured resin layer, the transparent resin film is more likely to be affected by heating, and a transparent conductive film Can be designed.

It is preferable that the transparent conductive film of the present invention further comprises one or more optical adjustment layers between the first cured resin layer and the transparent conductive film. The refractive index can be controlled by the optical adjusting layer. Therefore, even when the transparent conductive film is patterned, the difference in reflectance between the pattern forming portion and the pattern opening portion can be reduced and the transparent conductive film pattern can hardly be seen. The visibility is improved.

It is possible to design the transparent conductive film so that the curling amount is more likely to be generated by adjusting the substrate heat shrinkage difference in the MD direction and the TD direction and reducing the shrinkage force of the base material by passing the annealing process after passing through the optical adjustment layer.

The second cured resin layer in the present invention preferably comprises a resin and particles. This makes it possible to more reliably realize the anti-blocking property which can withstand the roll-to-roll production method, and to improve the transportability.

In the transparent resin film of the present invention, the amorphous resin is a cycloolefin resin, the thickness is 20 to 75 占 퐉, the glass transition temperature is 130 占 폚 or more, and the transparent conductive film is heated at 130 占 폚 for 90 minutes The heat shrinkage rate after heating is preferably less than 0.2% in the MD and TD directions. Since the thickness of the transparent resin film is in a relatively thin range, the transparent conductive film can be easily designed to be easily affected by heating and to generate curling. In addition, by using a cyclo-olefin-based resin having a high glass transition temperature and using a transparent conductive film having a small heat shrinkage ratio, excessive heat shrinkage after the heating step can be suppressed and curling can be controlled at a higher level .

The optical adjustment layer in the present invention preferably contains a binder resin and fine particles, and has a refractive index of 1.6 to 1.8 and a thickness of 40 to 150 nm. By including fine particles in the optical adjusting layer, the refractive index of the optical adjusting layer itself can easily be adjusted. Further, by setting the thickness of the optical adjustment layer within the above-mentioned range, it is possible to control the formation of a continuous coating film so as to ensure transparency and not to have a large influence on curling.

The transparent conductive film in the present invention is preferably made of indium-tin composite oxide (ITO) and has a thickness of 10 to 35 nm. As a result, transparency can be ensured, visibility can be improved even when used in a touch panel or the like, and the direction and amount of curling can be designed.

The transparent conductive film laminate of the present invention is preferably a laminate of a transparent conductive film obtained by laminating a glass substrate on the side opposite to the transparent conductive film of the transparent conductive film with a pressure-sensitive adhesive layer interposed therebetween. Since the transparent conductive film of the present invention is designed so as to greatly curl in the concave direction when the transparent conductive film is placed downward, it is possible to suppress the generation of curl after the heating process in the transparent conductive film laminate to which the parchment- It is possible to secure the yield of the subsequent process.

The transparent conductive film laminate of the present invention was cut to 210 mm x 260 mm and the difference (A - B) between the average curl value A at the four corner portions and the curl value B at the center portion after heating the transparent conductive film as an upper surface at 130 DEG C for 90 minutes, Is preferably 2.0 mm or less. Thereby, generation of curl can be suppressed even after the heating process, and the subsequent process yield can be secured.

The touch panel of the present invention is preferably obtained by using the above-mentioned transparent conductive film laminate. When the transparent conductive film laminate is used, curling after the heating process such as drying can be suppressed, so that the transparent conductive film laminate can be processed and transported easily, and the working efficiency is improved.

1 is a schematic cross-sectional view of a transparent conductive film according to an embodiment of the present invention.
2 is a schematic cross-sectional view of a transparent conductive film according to another embodiment of the present invention.
3 is a schematic cross-sectional view of a transparent conductive film laminate according to an embodiment of the present invention.

Embodiments of the transparent conductive film laminate of the present invention will be described below with reference to the drawings. However, in some or all of the drawings, portions unnecessary for description are omitted and there are portions shown enlarged or reduced in order to facilitate explanation. The terms indicating the positional relationship such as the vertical direction and the like are used merely for ease of explanation, and there is no intention to limit the constitution of the present invention at all.

≪ Structure of transparent conductive film and laminate >

Fig. 1 is a cross-sectional view schematically showing one embodiment of the transparent conductive film of the present invention, Fig. 2 is a cross-sectional view schematically showing another embodiment of the transparent conductive film of the present invention, Of the transparent conductive film laminate according to the present invention. The transparent conductive film 10 shown in Figs. 1 and 2 has a structure in which a first cured resin layer 2 and a transparent conductive film 3 are formed in this order on one side of a transparent resin film 1, A second cured resin layer (4) is formed on the other surface side of the resin film (1). As shown in Fig. 2, a single optical adjustment layer 5 may be provided between the first cured resin layer 2 and the transparent conductive film 3, but two or more optical adjustment layers 5 may be provided. The first cured resin layer 2 and the second cured resin layer 4 include those which function as an anti-blocking layer or a hard coat layer. 3, the transparent conductive film laminate is a laminate in which the glass substrate 6 is laminated on the surface of the transparent conductive film 10 opposite to the transparent conductive film 3 with the adhesive layer 7 interposed therebetween do.

≪ Transparent conductive film &

The transparent conductive film has a first cured resin layer and a transparent conductive film in this order on one side of the transparent resin film and a second cured resin layer on the other side of the transparent resin film. One or more optical adjustment layers may be additionally provided between the first cured resin layer and the transparent conductive film. In the transparent conductive film, the heat shrinkage ratio in the MD direction and the TD direction when heated at 130 占 폚 for 90 minutes is preferably less than 0.2%, more preferably 0.2% or less, still more preferably 0.15% Or less. The lower limit value is not particularly limited, but is preferably 0.01% or more. Thereby, a transparent conductive film excellent in workability, transparency, and the like can be obtained, and the amount and direction of curling after the heating process such as drying can be controlled, so that the transparent conductive film laminate can be processed and transported easily.

The difference (A - B) between the average curl value A at the four corner portions and the curl value B at the center portion after the transparent conductive film was cut to 50 cm x 50 cm and heated at 130 占 폚 for 90 minutes with the transparent conductive film as the lower surface was 5 mm or more More preferably 8 mm or more, and further preferably 10 mm or more. The upper limit value is not particularly limited, but is preferably 50 mm or less, more preferably 40 mm or less, and further preferably 30 mm or less. When the curling amount of the transparent conductive film is set to be large in this manner, the curl after the heating process can be made very small in the transparent conductive film laminate after being laminated with the thin glass substrate. This makes it possible to suppress the curling of the transparent conductive film after heating by crystallization of the transparent conductive film, metal wiring processing, etc., so that stable and continuous processing and transportation can be achieved, and the subsequent process yield can be ensured.

(Transparent resin film)

The transparent resin film is formed of an amorphous resin and has characteristics of high transparency and low water absorption. The use of an amorphous resin makes it possible to control the optical characteristics of the transparent conductive film. The amorphous resin is not particularly limited, but is preferably excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, and the like. Examples of the amorphous resin include acrylic resins such as polycarbonate, cycloolefin, polyvinyl chloride, and polymethyl methacrylate (ABS resin), polyarylate, poly (meth) acrylate, polyacrylonitrile, styrene copolymer, polystyrene, polystyrene, polymethyl methacrylate styrene copolymer, polyacrylonitrile, polyacrylonitrile styrene copolymer, high impact polystyrene (HIPS), acrylonitrile butadiene styrene copolymer Sulfone, polyethersulfone, polyphenylene ether, and the like. From the viewpoints of high transparency, low water absorption, heat resistance and the like, cycloolefin resin, polycarbonate resin and the like are preferable.

The cycloolefin-based resin is not particularly limited as long as it is a resin having a unit of a monomer comprising a cyclic olefin (cycloolefin). As the cycloolefin-based resin used for the transparent resin film, a cycloolefin polymer (COP) or a cycloolefin copolymer (COC) may be used. The cycloolefin copolymer refers to an amorphous cyclic olefin resin that is a copolymer of a cyclic olefin and an olefin such as ethylene.

As the cyclic olefin, there are a polycyclic olefin and a monocyclic cyclic olefin. Examples of such polycyclic cyclic olefins include norbornene, methylnorbornene, dimethylnorbornene, ethylnorbornene, ethylidene norbornene, butyl norbornene, dicyclopentadiene, dihydrodicyclopenta Dienes, methyldicyclopentadiene, dimethyldicyclopentadiene, tetracyclododecene, methyltetracyclododecene, dimethylcyclotetradodecene, tricyclopentadiene, tetracyclopentadiene, and the like. Examples of monocyclic cyclic olefins include cyclobutene, cyclopentene, cyclooctene, cyclooctadiene, cyclooctatriene, cyclododecatriene, and the like.

The cycloolefin resin is also available as a commercial product, and examples thereof include "ZEONOR" manufactured by Nippon Zeon Co., "ARTON" manufactured by JSR Corporation, "TOPAS" manufactured by Polyplastics Co., and "APEL" manufactured by Mitsui Chemicals, Inc.

The polycarbonate resin is not particularly limited, and examples thereof include an aliphatic polycarbonate, an aromatic polycarbonate, and an aliphatic-aromatic polycarbonate. Specifically, for example, as a polycarbonate (PC) using bisphenols, bisphenol A polycarbonate, branched bisphenol A polycarbonate, foam polycarbonate, copolycarbonate, block copolycarbonate, polyester carbonate, polyphosphonate carbonate , Diethylene glycol bisallyl carbonate (CR-39), and the like. Polycarbonate resins also include blends with other components such as bisphenol A polycarbonate blends, polyester blends, ABS blends, polyolefin blends, and styrene-maleic anhydride copolymer blends. Commercially available products of polycarbonate resin include "Opon" manufactured by Kawasaki Co., Ltd., "Panlight" manufactured by Teijin Co., Ltd., and "Yufilon (polycarbonate containing ultraviolet absorber)" manufactured by Mitsubishi Gas Chemical Company.

The surface of the transparent resin film is subjected to an etching treatment or undercoating treatment such as sputtering, corona discharge, a flame, an ultraviolet ray irradiation, an electron beam irradiation, a chemical conversion and an oxidation in advance to form a cured resin layer or a transparent conductive film May be improved. Before the formation of the cured resin layer or the transparent conductive film, the surface of the transparent resin film may be damped and cleaned by solvent cleaning or ultrasonic cleaning as necessary.

The thickness of the transparent resin film is preferably in the range of 20 to 75 占 퐉, more preferably in the range of 25 to 70 占 퐉, and still more preferably in the range of 30 to 65 占 퐉. If the thickness of the transparent resin film is less than the lower limit of the above range, the mechanical strength is insufficient, and the operation of continuously forming the transparent conductive film by making the film base in roll form may become difficult. On the other hand, if the thickness exceeds the upper limit of the above range, the scratch resistance of the transparent conductive film and the rubbing characteristic for the touch panel may not be improved. If the thickness is within the above range, it is more likely to be affected by heating. Therefore, when the transparent conductive film of the transparent conductive film is set down, it can be designed so as to curl in the concave direction in advance, It is possible to suppress the generation of curl after the heating process when the laminate is formed.

The glass transition temperature (Tg) of the amorphous resin of the transparent resin film is not particularly limited, but is preferably 130 占 폚 or higher, more preferably 150 占 폚 or higher, and even more preferably 160 占 폚 or higher. This makes it possible to suppress the generation of curl after the heating step such as drying when the transparent conductive film laminate is used, so that the transparent conductive film laminate can be processed and transported easily.

The heat shrinkage rate in the MD direction and the TD direction when heated to 130 占 폚 for 90 minutes in the resin film forming the transparent resin film (the film before the lamination of the cured resin layers and before the heat treatment) is 0.3% or less , More preferably 0.2% or less, and further preferably 0.1% or less. Thereby, a transparent resin film excellent in workability, transparency, dimensional stability at the time of heating, and the like is obtained. In addition, when the transparent conductive film laminate is used as a transparent conductive film laminate, curling after the heating process such as drying can be suppressed, so that the transparent conductive film laminate can be processed and transported easily.

The transparent resin film can be easily formed into a low-retardation film having a retardation R0 in the in-plane direction of 0 nm to 10 nm or a lambda / 4 film having an in-plane retardation of about 80 nm to 150 nm, When used, the visibility can be improved. The in-plane retardation R0 refers to the retardation value in the plane of the retardation film (layer) measured at 23 deg. C with light having a wavelength of 589 nm.

(Cured resin layer)

The cured resin layer includes a first cured resin layer formed on one side of the transparent resin film and a second cured resin layer formed on the other side of the transparent resin film. A transparent resin film formed of an amorphous resin is liable to be scratched in various steps such as formation of a transparent conductive film, patterning of a transparent conductive film, mounting on an electronic device, and so on. And a second cured resin layer is formed.

The cured resin layer is a layer obtained by curing the curable resin. The cured resin layer preferably contains a resin and particles. As the resin to be used, a thermosetting resin, an ultraviolet-curable resin, an electron beam-curable resin, a two-liquid mixed resin, and the like can be used as the resin having sufficient strength as a film after formation of a cured resin layer and having transparency without particular limitation . Among them, an ultraviolet curable resin which can efficiently form a cured resin layer by a simple processing operation by a curing treatment by ultraviolet irradiation is preferable.

Examples of the ultraviolet curable resin include various types such as polyester type, acrylic type, urethane type, amide type, silicone type, epoxy type and the like, and include ultraviolet curable type monomers, oligomers, polymers and the like. The ultraviolet curable resin preferably used is an acrylic resin or an epoxy resin, more preferably an acrylic resin.

The cured resin layer may contain particles. By blending the particles in the cured resin layer, it is possible to form ridges on the surface of the cured resin layer, and the anti-blocking property can be preferably imparted to the transparent conductive film.

As the above-mentioned particles, those having transparency such as various metal oxides, glass, and plastic can be used without particular limitation. For example, inorganic particles such as silica, alumina, titania, zirconia and calcium oxide, and various polymers such as polymethyl methacrylate, polystyrene, polyurethane, acrylic resin, acryl-styrene copolymer, benzoguanamine, melamine and polycarbonate Based organic particles and silicon-based particles, which are crosslinked or uncrosslinked. One or more of the above-mentioned particles can be appropriately selected and used, but organic particles are preferable. As the organic particles, an acrylic resin is preferable from the viewpoint of the refractive index.

The most frequent particle diameter of the particles can be suitably set in consideration of the relationship between the protrusion of the ridges of the cured resin layer and the thickness of the flat region other than the ridges, and is not particularly limited. From the viewpoint of sufficiently imparting blocking resistance to the transparent conductive film and sufficiently suppressing the increase in haze, the particle size of the particles is preferably from 0.5 to 5 mu m, more preferably from 1.0 to 2 mu m. In this specification, the term " minimum particle diameter " means the particle diameter indicating the maximum value of the particle distribution, and is measured under a predetermined condition (Sheath liquid : Ethyl acetate, measurement mode: HPF measurement, measurement method: total count). The sample to be measured is prepared by diluting the particles with 1.0% by weight of ethyl acetate and uniformly dispersing them using an ultrasonic cleaner.

The content of the particles is preferably 0.05 to 1.0 part by weight, more preferably 0.1 to 0.5 part by weight, and most preferably 0.2 to 0.3 part by weight based on 100 parts by weight of the resin solid content. If the content of the particles in the cured resin layer is small, it is likely that ridges sufficient to impart anti-blocking properties and slipperiness to the surface of the cured resin layer are liable to be formed. On the other hand, if the content of the particles is too large, the haze of the transparent conductive film tends to increase due to light scattering caused by the particles, and the visibility tends to decrease. If the content of the particles is too large, streaks may be generated at the time of forming the cured resin layer (at the time of applying the solution), resulting in deterioration of visibility or uneven electrical characteristics of the transparent conductive film.

The cured resin layer is formed by applying a resin composition containing a curable resin and particles, a cross-linking agent, an initiator, a sensitizer, and the like, as needed, onto a transparent resin film, and when the resin composition contains a solvent, And curing it by application of heat, an active energy ray or both. The heat may be a known means such as an air circulating oven or an IR heater, but is not limited to these methods. Examples of the active energy ray include, but are not limited to, ultraviolet ray, electron ray, gamma ray and the like.

The cured resin layer can be formed by a wet coating method (coating method) or the like using the above materials. For example, when indium oxide (ITO) containing tin oxide is formed as a transparent conductive film, crystallization time of the transparent conductive film can be shortened if the surface of the cured resin layer as a ground layer is smooth. From this viewpoint, it is preferable that the cured resin layer is formed by a wet coating method.

The thickness of the first cured resin layer and the thickness of the second cured resin layer are both preferably 2 탆 or less, more preferably 0.1 탆 to 1.5 탆, and still more preferably 0.3 탆 to 1.2 탆. It is preferable that the thickness of the second cured resin layer is equal to or smaller than the thickness of the first cured resin layer. That is, the thickness of the second cured resin layer is preferably 10 to 100%, more preferably 20 to 90%, and further preferably 30 to 80% of the thickness of the first cured resin layer. Thus, it is possible to prevent the occurrence of scratches in the transparent resin film when the film is transported by the roll-to-roll method. When the thickness of the cured resin layer is in the above range, deterioration of the visibility of the touch panel or the like can be prevented, and in the case where the transparent conductive film of the transparent conductive film is made downward, The generation of curl after the heating process can be suppressed when the laminated paper is made into a transparent conductive film laminate.

(Transparent conductive film)

The transparent conductive film can be formed on the transparent resin film, but is preferably formed on the first cured resin layer formed on one side of the transparent resin film. The constituent material of the transparent conductive film is not particularly limited as long as it contains an inorganic substance and may be selected from the group consisting of indium, tin, zinc, gallium, antimony, titanium, silicon, zirconium, magnesium, aluminum, gold, silver, copper, palladium and tungsten A metal oxide of at least one selected metal is preferably used. The metal oxide may further contain metal atoms shown in the above group, if necessary. For example, indium oxide (ITO) containing tin oxide, tin oxide (ATO) containing antimony and the like are preferably used.

Although the thickness of the transparent conductive film is not particularly limited, it is preferable to set the thickness to 10 to 35 nm in order to form a continuous film having good conductivity with a surface resistance of 1 x 10 ³ ? /? Or less. If the film thickness is excessively increased, the transparency is lowered. Therefore, the film thickness is more preferably 15 to 35 nm, and still more preferably 20 to 30 nm. If the thickness of the transparent conductive film is less than 10 nm, the electrical resistance of the film surface becomes high and it becomes difficult to form a continuous film. On the other hand, when the thickness of the transparent conductive film exceeds 35 nm, transparency may be lowered. In addition, when the transparent conductive film of the transparent conductive film is made downward, the transparent conductive film can be designed so as to greatly curl in the concave direction in advance by forming the transparent conductive film with the above thickness on the first cured resin layer.

The method of forming the transparent conductive film is not particularly limited, and conventionally known methods can be employed. Specifically, for example, a dry process such as a vacuum deposition method, a sputtering method, and an ion plating method can be exemplified. An appropriate method may be employed depending on the required film thickness.

The transparent conductive film can be crystallized by a thermal annealing treatment (for example, at 80 to 150 DEG C for about 30 to 90 minutes in an atmospheric environment) if necessary. By crystallizing the transparent conductive film, transparency and durability are improved in addition to the resistance of the transparent conductive film. The means for making the amorphous transparent conductive film into crystalline is not particularly limited, but an air circulating oven, IR heater, or the like is used.

For the definition of "crystalline", a transparent conductive film having a transparent conductive film formed on a transparent resin film was immersed in hydrochloric acid of 5 wt% concentration at 20 ° C. for 15 minutes, washed with water, dried, When the measurement is carried out with a tester, and the resistance between the terminals does not exceed 10 k ?, it is assumed that the telephone to the crystalline of the ITO film is completed. In addition, the surface resistance value can be measured by a four-terminal method in accordance with JIS K7194.

The transparent conductive film may be patterned by etching or the like. The patterning of the transparent conductive film can be carried out by using a conventionally known technique of photolithography. As the etching solution, an acid is preferably used. Examples of the acid include inorganic acids such as hydrogen chloride, hydrogen bromide, sulfuric acid, nitric acid and phosphoric acid, organic acids such as acetic acid, and mixtures thereof, and aqueous solutions thereof. For example, in a transparent conductive film used in a capacitive touch panel or a matrix type resistive touch panel, it is preferable that the transparent conductive film is patterned in a stripe shape. Further, when the transparent conductive film is patterned by etching, if crystallization of the transparent conductive film is performed first, patterning by etching may become difficult. Therefore, the annealing of the transparent conductive film is preferably performed after patterning the transparent conductive film.

(Optical adjustment layer)

One or more optical adjustment layers may be additionally provided between the first cured resin layer and the transparent conductive film. When the transmittance of the transparent conductive film is increased or the transparent conductive film is patterned, the difference in transmittance difference or reflectance between the pattern portion where the pattern remains and the opening portion where the pattern is not formed can be reduced, It is used to obtain film.

The optical adjustment layer preferably includes a binder resin and fine particles. Examples of the binder resin contained in the optical adjustment layer include acrylic resin, urethane resin, melamine resin, alkyd resin, siloxane polymer, organic silane condensate and the like, and an ultraviolet curable resin including an acrylic resin is preferable .

The refractive index of the optical adjusting layer is preferably 1.6 to 1.8, more preferably 1.62 to 1.78, and further preferably 1.65 to 1.75. Thereby, the difference in transmittance and the difference in reflectance can be reduced, and a transparent conductive film excellent in visibility can be obtained.

The optical adjustment layer may have fine particles having an average particle diameter of 1 nm to 500 nm. The content of the fine particles in the optical adjusting layer is preferably 0.1 wt% to 90 wt%. The average particle diameter of the fine particles used in the optical adjustment layer is preferably in the range of 1 nm to 500 nm, and more preferably in the range of 5 nm to 300 nm, as described above. The content of the fine particles in the optical adjusting layer is more preferably 10% by weight to 80% by weight, and still more preferably 20% by weight to 70% by weight. By containing fine particles in the optical adjustment layer, it is possible to easily adjust the refractive index of the optical adjustment layer itself.

Examples of the inorganic oxide that forms the fine particles include fine particles such as silicon oxide (silica), hollow nanosilica, titanium oxide, aluminum oxide, zinc oxide, tin oxide, zirconium oxide and niobium oxide. Among these, fine particles of silicon oxide (silica), titanium oxide, aluminum oxide, zinc oxide, tin oxide, zirconium oxide and niobium oxide are preferable, and zirconium oxide is more preferable. These may be used singly or in combination of two or more.

The optical adjustment layer may contain other inorganic substances. Minerals _{include, NaF (1.3), Na 3} AlF 6 (1.35), LiF (1.36), MgF 2 (1.38), CaF 2 (1.4), BaF 2 (1.3), BaF 2 (1.3), LaF 3 (1.55 ), CeF (1.63) (numerical values in parentheses indicate refractive index).

The optical adjustment layer can be formed using the above materials by a coating method such as a wet coating method, a gravure coating method or a bar coating method, a vacuum evaporation method, a sputtering method, an ion plating method and the like. For example, when indium oxide (ITO) containing tin oxide is formed as a transparent conductive film, crystallization time of the transparent conductive layer may be shortened if the surface of the resin layer as a ground layer is smooth. From this viewpoint, it is preferable that the resin layer is formed by a wet coating method.

The thickness of the optical adjustment layer is preferably 40 nm to 150 nm, more preferably 50 nm to 130 nm, and even more preferably 70 nm to 120 nm. If the thickness of the optical adjustment layer is excessively small, it is difficult to form a continuous coating. If the thickness of the optical adjustment layer is excessively large, the transparency of the transparent conductive film tends to be lowered or cracks tend to occur.

(Metal wiring)

The metal wiring can be formed by etching after the metal layer is formed on the transparent conductive film, but it is preferable to form the metal wiring by using the photosensitive metal paste as described below. That is, after the transparent conductive film is patterned, the metal wiring is coated with a photosensitive conductive paste described later on the transparent resin film or the transparent conductive film to form a photosensitive metal paste layer, and a photomask is stacked or brought close Exposure is performed on the photosensitive metal paste layer through a photomask, then development is carried out, a pattern is formed, and then a drying process is performed. That is, it is possible to form a metal wiring pattern by a known photolithography method or the like.

The photosensitive conductive paste preferably includes conductive particles such as a metal powder and a photosensitive organic component. As the material of the conductive particles of the metal powder, it is preferable to include at least one kind selected from the group consisting of Ag, Au, Pd, Ni, Cu, Al and Pt, and more preferably Ag. The volume average particle diameter of the conductive particles of the metal powder is preferably 0.1 mu m to 2.5 mu m.

The conductive particles other than the metal powder may be metal coated resin particles in which the surface of the resin particle is coated with a metal. As the material of the resin particles, the above-mentioned particles are included, but an acrylic resin is preferable. The metal-coated resin particles are obtained by reacting the surface of the resin particles with a silane coupling agent and coating the surface with a metal. By using the silane coupling agent, the dispersion of the resin component is stabilized and uniform metal coated resin particles can be formed.

The photosensitive conductive paste may further contain glass frit. The glass frit preferably has a volume average particle diameter of 0.1 mu m to 1.4 mu m, a 90% particle diameter of 1 to 2 mu m and a top size of 4.5 mu m or less. The composition of the glass frit is not particularly limited, but it is preferable that Bi ₂ O ₃ is blended in the range of 30 wt% to 70 wt% with respect to the total amount. The oxides that may be contained in addition to Bi ₂ O ₃ may include SiO ₂ , B ₂ O ₃ , ZrO ₂ , and Al ₂ O ₃ . Free glass frit that is substantially free of Na ₂ O, K ₂ O, and Li ₂ O.

The photosensitive organic component preferably comprises a photosensitive polymer and / or a photosensitive monomer. Examples of the photosensitive polymer include a polymer having a carbon-carbon double bond such as methyl (meth) acrylate or ethyl (meth) acrylate, or a polymer having a structure selected from the group consisting of a polymer having a carbon- A reactive group is added, and the like are preferably used. Preferred examples of the photoreactive group include ethylenic unsaturated groups such as vinyl, allyl, acryl, and methacryl groups. The content of the photosensitive polymer is preferably 1 to 30% by weight and 2 to 30% by weight.

Examples of the photosensitive monomer include (meth) acrylate monomers such as methacryl acrylate and ethyl acrylate,? -Methacryloxypropyltrimethoxysilane and 1-vinyl-2-pyrrolidone, One or more of them may be used.

In the photosensitive conductive paste, the photosensitive organic component is preferably contained in an amount of 5 to 40% by weight based on 100 parts by weight of the metal powder from the viewpoint of light sensitivity, more preferably 10 to 30 parts by weight. In the photosensitive conductive paste of the present invention, a photo polymerization initiator, a sensitizer, a polymerization inhibitor, and an organic solvent are preferably used, if necessary.

The thickness of the metal layer is not particularly limited. For example, when a part of the surface of the metal layer is removed by etching or the like to form the pattern wiring, the thickness of the metal layer is appropriately set so that the formed pattern wiring has a desired resistance value. Therefore, the thickness of the metal layer is preferably 0.01 to 200 탆, more preferably 0.05 to 100 탆. When the thickness of the metal layer is within the above range, the resistance of the pattern wiring is not excessively increased and the power consumption of the device is not increased. Further, the production efficiency of the film formation of the metal layer is increased, the amount of heat accumulated at the time of film formation is reduced, and heat wrinkles are less likely to occur in the film.

When the transparent conductive film is a transparent conductive film for a touch panel used in combination with a display, a portion corresponding to the display portion is formed by a patterned transparent conductive film, and the metal wiring fabricated from the photosensitive conductive paste is a non- For example, a peripheral portion). The transparent conductive film may be used in a non-display portion, and in this case, a metal wiring may be formed on the transparent conductive film.

<Transparent conductive film laminate>

The transparent conductive film laminate is formed by laminating a glass substrate on the other surface side of the transparent conductive film of the transparent conductive film with an adhesive layer interposed therebetween. The transparent conductive film laminate was prepared by cutting the transparent conductive film laminate to 210 mm x 260 mm and measuring the difference between the average curl value A of the four corner portions after heating at 130 DEG C for 90 minutes with the transparent conductive film as an upper surface and the curl value B A - B) is preferably 2.0 mm or less, more preferably less than 2.0 mm, and further preferably 1.8 mm or less. The lower limit value is not particularly limited, but is preferably 0.5 mm or more. When the curl amount is suppressed in this way, air-suction can be performed when the transparent conductive film laminate is transported, and the film can be transported continuously.

(Glass substrate)

The glass substrate is laminated with a transparent conductive film through a pressure-sensitive adhesive layer on the other surface side of the transparent conductive film of the transparent conductive film. The material for forming the glass substrate is not particularly limited, but is preferably excellent in transparency, surface smoothness, thermal stability, moisture barrier property, isotropy, and the like, and examples thereof include soda lime glass and borosilicate glass. These glasses may be chemically reinforced or may have an alkali leaching prevention layer formed on the surface thereof. The glass surface may be treated with a silane coupling agent in order to increase the adhesion with other layers.

The thickness of the glass substrate is preferably 0.1 to 1.5 mm, more preferably 0.3 to 1.0 mm. If the thickness is too thin, the glass tends to break when the transparent conductive film laminate is heated. If it is too thick, it is difficult to reduce the thickness of the display and the flexibility is lowered. When a glass substrate having such a thickness in this range is placed below a transparent conductive film, the transparent conductive film laminated body is bonded to a transparent conductive film designed to greatly curl in the concave direction in advance, thereby suppressing curling after the heating step .

(Pressure-sensitive adhesive layer)

As the pressure-sensitive adhesive layer, the following pressure-sensitive adhesives can be used without particular limitation as long as they have transparency. Specific examples of the pressure sensitive adhesive include acrylic polymers, silicone polymers, polyesters, polyurethanes, polyamides, polyvinyl ethers, vinyl acetate / vinyl chloride copolymers, modified polyolefins, epoxy, fluorine, natural rubber, , And the like can be appropriately selected and used as the base polymer. In particular, an acrylic pressure-sensitive adhesive is preferably used because it has excellent optical transparency, exhibits adhesive properties such as appropriate wettability, cohesiveness and adhesiveness, and is also excellent in weather resistance and heat resistance.

The method of forming the pressure-sensitive adhesive layer is not particularly limited, and a method of applying a pressure-sensitive adhesive composition to a release liner, drying and then transferring the pressure-sensitive adhesive composition onto a glass substrate (transfer method), directly applying a pressure- And the like. Further, a tackifier, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a silane coupling agent and the like may be suitably used for the pressure-sensitive adhesive, if necessary.

The preferable thickness of the pressure-sensitive adhesive layer is 5 占 퐉 to 100 占 퐉, more preferably 10 占 퐉 to 50 占 퐉, and still more preferably 15 占 퐉 to 35 占 퐉.

<Touch panel>

The transparent conductive film laminate can be suitably applied as a transparent electrode of an electronic device such as a touch panel such as a capacitive type or a resistive type. Further, since the transparent conductive film laminate of the present invention is laminated on a glass substrate, the transparent conductive film laminate can be suitably applied as a transparent electrode of an electronic device such as a touch panel.

At the time of forming the touch panel, the above-described transparent conductive film laminate can be used. In the present invention, a laminate in which a glass substrate is bonded with a transparent adhesive layer interposed therebetween is formed on the side of the transparent conductive film on which the transparent conductive film is not formed. The glass substrate may be composed of one substrate, Or a laminate of the above-described substrates (for example, a laminate of transparent pressure-sensitive adhesive layers interposed therebetween). The pressure-sensitive adhesive layer used for bonding the transparent conductive film to the substrate may be any of those having transparency as described above without particular limitation.

When the transparent conductive film laminate is used for forming a touch panel, it is possible to suppress the amount and direction of curling after the heating process such as drying, so that the transparent conductive film laminate can be easily transported, Is excellent in handling property. Therefore, a touch panel having excellent transparency and visibility can be manufactured with high productivity. If it is outside the use of a touch panel, it can be used as a shielding application for shielding electromagnetic waves and noise generated from electronic devices.

&Lt; Method for producing transparent conductive film laminate &gt;

A method for producing a transparent conductive film laminate of the present invention includes the steps of preparing a transparent conductive film having a transparent conductive film and an amorphous transparent conductive film formed on the transparent resin film; A step of laminating a glass substrate, and a step of heat-processing the transparent conductive film laminate. Examples of the step of heat-processing the transparent conductive film laminate include a step of crystallizing the transparent conductive film, a step of drying the metal wiring formed by the photosensitive metal paste layer, and the like. It is preferable that the transparent conductive film laminate is subjected to such a heating process. Thus, since the transparent conductive film is designed to curl in the concave direction in advance when the transparent conductive film is disposed below, the occurrence of curling in the transparent conductive film laminate can be suppressed.

The transparent conductive film used in the step of preparing the transparent conductive film may be formed by forming a cured resin layer on a transparent resin film and then forming a transparent conductive film or by forming a transparent resin laminate having a cured resin layer on a transparent resin film A transparent conductive film may be formed on the cured resin layer, or a transparent conductive film having a cured resin layer and a transparent conductive film formed on a transparent resin film may be obtained. A transparent resin laminate previously formed may also be obtained and used for the above-mentioned optical adjustment layer.

In the step of laminating the glass substrate, a pressure-sensitive adhesive layer is formed on the release substrate, the pressure-sensitive adhesive layer is transferred to the glass substrate, and a pressure-sensitive adhesive layer is provided on the side where the transparent resin film of the second cured resin layer of the transparent conductive film is not formed And the pressure-sensitive adhesive layer may be directly formed on the glass substrate. Alternatively, a glass substrate may be laminated by forming a pressure-sensitive adhesive layer on the surface opposite to the transparent conductive film of the transparent conductive film.

In order to crystallize the constituent components of the transparent conductive film, it is introduced into the heat treatment step. The heating temperature is preferably, for example, 130 DEG C or lower, more preferably 120 DEG C or lower, and the treatment time is, for example, 15 to 180 minutes. Thereafter, the transparent conductive film is etched to form the pattern portion by the pattern. In the present invention, after the transparent conductive film is patterned, the photosensitive conductive paste described above is applied on the transparent resin film or the transparent conductive film, a photosensitive metal paste layer is formed, a photomask is stacked or brought close to each other, It is preferable to further include a step of exposing the photosensitive metal paste layer through a mask or obtaining a metal wiring by screen printing or the like. The drying step is preferably carried out at 130 ° C or lower, and preferably 120 ° C or lower. The heat treatment for crystallizing the transparent conductive film laminate, the subsequent etching process, and the metal wiring process are performed in a single sheet process because there is a patterning alignment of the photomask, the transparent conductive film, and the metal wiring. At this time, a step of fixing to a suction plate for alignment is necessary. However, since the amount and direction of curl can be controlled even when dried in the above-mentioned temperature range, it becomes possible to avoid the step of fixing to the suction plate.

Example

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples unless the gist thereof is exceeded.

[Example 1]

(Preparation of spherical particle-containing curable resin composition)

, 100 parts by weight of an ultraviolet ray curable resin composition (trade name "UNIDIC (registered trademark) RS29-120" manufactured by DIC Corporation) and 0.3 part by weight of acrylic spherical particles having a maximum particle diameter of 1.9 μm (trade name "MX-180TA" Containing spherical particle-containing curable resin composition was prepared.

(Formation of Cured Resin Layer)

The prepared spherical particle-containing curable resin composition was applied to one side of a polycycloolefin film (trade name "ZEONOR (registered trademark)" manufactured by Nippon Zeon Co., Ltd.) having a thickness of 35 탆 and a glass transition temperature of 165 캜 to form a coating layer . Subsequently, ultraviolet rays were irradiated from the side where the coating layer was formed to the coating layer to form a second cured resin layer so as to have a thickness of 1.0 mu m. The first cured resin layer was formed on the other surface of the polycycloolefin film so that the thickness and the thickness of the first cured resin layer were 1.0 占 퐉, in the same manner as in the first and second embodiments, except that spherical particles were not added.

(Formation of optical adjustment layer)

An ultraviolet curable composition containing zirconia particles having refractive index of 1.62 (trade name &quot; Obstar Z7412 &quot;, trade name, manufactured by JSR Corporation) was applied as an optical adjustment layer to the first cured resin layer side of the polycycloolefin film on both sides of which a cured resin layer was formed, . Subsequently, ultraviolet rays were irradiated from the side where the coating layer was formed to the coating layer to form an optical adjustment layer so as to have a thickness of 100 nm.

(Formation of transparent conductive film)

Next, a polycycloolefin film having an optical adjustment layer formed therein was placed in a spiral-type sputtering apparatus, and an amorphous indium-tin oxide layer (composition: SnO ₂ 10 wt%) having a thickness of 27 nm was formed on the surface of the optical adjustment layer. To form a transparent conductive film. Thus, a transparent conductive film was produced.

(Formation of transparent conductive film laminate)

By an ordinary solution polymerization, an acryl-based polymer having a weight average molecular weight of 60,000 was obtained with butyl acrylate / acrylic acid = 100/6 (weight ratio). To the 100 parts by weight of the acryl-based polymer, 6 parts by weight of an epoxy cross-linking agent (trade name "TETRADE C (registered trademark)" manufactured by Mitsubishi Gas Chemical Company) was added to prepare an acrylic pressure-sensitive adhesive. After the acrylic pressure-sensitive adhesive obtained as described above was applied (thickness after drying: 20 탆) onto a thin soda glass cut to 210 mm x 260 mm with a thickness of 0.4 mm, a transparent conductive film was laminated To prepare a transparent conductive film laminate.

[Example 2]

A polycycloolefin film (trade name "ZEONOR (registered trademark)" manufactured by Nippon Zeon Co., Ltd.) having a thickness of 50 μm was used as the transparent resin film in Example 1, and the maximum particle diameter of the spherical particles contained in the second cured resin layer 0.8 μm, and that the thickness of the second cured resin layer was 0.5 μm, a transparent conductive film and a transparent conductive film laminate were produced in the same manner as in Example 1.

[Example 3]

A transparent conductive film and a transparent conductive film were formed in the same manner as in Example 1 except that the transparent conductive film was formed after annealing treatment at 150 캜 for 3 minutes by the roll- Thereby forming a laminate.

[Example 4]

Except that a polycycloolefin film (trade name "ZEONOR (registered trademark)" manufactured by Zeon Corporation) having a thickness of 50 μm was used as the transparent resin film in Example 1, a transparent conductive film and a transparent conductive film Thereby producing a film laminate.

[Example 5]

Except that a polycycloolefin film (trade name "ZEONOR (registered trademark)" manufactured by Zeon Corporation) having a thickness of 50 μm was used as the transparent resin film in Example 3, a transparent conductive film and a transparent conductive film Thereby producing a film laminate.

[Comparative Example 1]

A polycycloolefin film (trade name "ZEONOR (registered trademark)" manufactured by Nippon Zeon Co., Ltd.) having a thickness of 50 μm was used as the transparent resin film in Example 1 and that having a thickness of the second cured resin layer of 3.0 μm A transparent conductive film and a transparent conductive film laminate were produced in the same manner as in Example 1. [

[Comparative Example 2]

Except that a polycycloolefin film (trade name "ZEONOR (registered trademark)" manufactured by Zeon Corporation) having a thickness of 75 μm was used as the transparent resin film in Example 1, a transparent conductive film and a transparent conductive film Thereby producing a film laminate.

[Comparative Example 3]

Example 1 was repeated except that a polyester resin (PET) (trade name &quot; DIAFOLE (registered trademark) &quot; manufactured by Mitsubishi Resin Co., Ltd.) having a thickness of 50 탆 and a glass transition temperature of 70 캜 was used as the transparent resin film in Example 1 A transparent conductive film and a transparent conductive film laminate were produced.

<Evaluation>

(1) Measurement of thickness

With respect to the thickness having a thickness of 1 占 퐉 or more, the measurement was carried out with a micro-gauge thickness meter (manufactured by Mitsutoyo Corporation). The thickness of less than 1 mu m or the thickness (100 nm) of the optical adjustment layer was measured with an instant multi-photometry system (MCPD2000 manufactured by OTSUKA ELECTRONICS CO., LTD.). The thickness of the nano-size, such as the thickness of the ITO film, was measured by using FB-2000A (manufactured by Hitachi High-Technologies Corporation) and a cross-sectional TEM observation was performed using HF-2000 (manufactured by Hitachi High- And the film thickness was measured. The evaluation results are shown in Table 1.

(2) Measurement of curl value in a transparent conductive film

The transparent conductive films obtained in Examples and Comparative Examples were cut into a size of 50 cm x 50 cm. After heating at 130 DEG C for 90 minutes with the ITO side down, the mixture was allowed to cool at room temperature (23 DEG C) for 1 hour. Thereafter, the sample was placed on a horizontal plane with the ITO side down, and the height from the horizontal plane of the four corner portions was measured, and the average value (curl value A) was calculated. In addition, the height (curl value B) from the horizontal plane of the central portion was measured. (A - B) obtained by subtracting the curl value B from the curl value A was calculated as a curl amount. The evaluation results are shown in Table 1.

(3) Measurement of curl value in the transparent conductive film laminate

The transparent conductive film laminate obtained in Examples and Comparative Examples was cut into a size of 210 mm x 260 mm x 0.4 mm. After the ITO side was heated to 130 DEG C for 90 minutes, the sample was allowed to cool at room temperature (23 DEG C) for 1 hour. Thereafter, the sample was placed on a horizontal surface with the ITO side up, and the height from the horizontal plane of the four corner portions was measured, and the average value (curl value A) was calculated. In addition, the height (curl value B) from the horizontal plane of the central portion was measured. (A - B) obtained by subtracting the curl value B from the curl value A was calculated as a curl amount. The evaluation results are shown in Table 1.

(4) Heat shrinkage ratio in MD direction and TD direction

The heat shrinkage ratios in the longitudinal direction (MD direction) and the transverse direction (TD direction) of the transparent conductive film were calculated as follows. Specifically, the transparent conductive film was cut to a width of 100 mm and a length of 100 mm (test piece), a cross was scratched at four corners, and a length (mm) of four points in the center of the cross- ) Was measured by a CNC three-dimensional measuring instrument (LEGEX774 manufactured by Mitsutoyo Co., Ltd.). Thereafter, the mixture was placed in an oven and subjected to a heat treatment (130 DEG C, 90 minutes). After cooling for 1 hour at room temperature, the lengths (mm) after heating in the MD direction and the TD direction of the four corners of the four corners were measured again by a CNC three-dimensional measuring machine and the measured values were substituted into the following formulas, The respective heat shrinkage ratios were obtained. The evaluation results are shown in Table 1. Heat shrinkage percentage (%) = [(length before heating (mm) - length after heating (mm)] / length before heating (mm)] 100

(5) Measurement of glass transition temperature (Tg)

The glass transition temperature (Tg) was determined in accordance with the provisions of JIS K7121.

(Results and Discussion)

In the transparent conductive films of Examples 1 to 5, curling occurred in the direction of the concave when the transparent conductive film was below and the amount of curling was as large as 7 to 28 mm. Thus, in the transparent conductive film laminate, The direction of occurrence was the concave direction when the transparent conductive film was raised, and curling was suppressed by the amount of curl generation of 1.1 to 2.0 mm. Further, in the transparent conductive films of Comparative Examples 1 and 2, the curling direction was a recessed direction when the transparent conductive film was below and the curling amount was as small as 2 to 4 mm. Therefore, in the transparent conductive film laminate, When the membrane was set up, the curling direction was large and the amount of curling was as large as 2.5 to 4.3 mm. From the above, it can be seen that there is a correlation between the curl of the transparent conductive film and the warp after the transparent conductive film laminate, and when the curling amount of 5 mm or more occurs in the transparent conductive film, the amount of curl in the transparent conductive film laminate can be reduced there was. In Comparative Example 3, the value of the Curl value is no problem, but a PET film is used for the base material, and since it has a high retardation, it can not be used as a base material for a base of a polarizer.

1: transparent resin film
2: the first cured resin layer
3: transparent conductive film
4: Second cured resin layer
5: Optical adjustment layer
6: glass substrate
7: Pressure-sensitive adhesive layer
10: transparent conductive film

Claims (10)

A transparent conductive film having a first cured resin layer and a transparent conductive film formed in this order on one side of a transparent resin film and a second cured resin layer formed on the other side of the transparent resin film,
Wherein the transparent resin film is made of an amorphous resin,
The transparent conductive film was cut into 50 cm x 50 cm and the difference (A - B) between the average curl value A at the four corner portions and the curl value B at the center portion after heating at 130 DEG C for 90 minutes with the transparent conductive film as the lower surface was 5 mm or more , Transparent conductive film. The method according to claim 1,
Wherein the thickness of the first cured resin layer and the thickness of the second cured resin layer are both 2 mu m or less and the thickness of the second cured resin layer is equal to or thinner than the thickness of the first cured resin layer, Conductive film. 3. The method according to claim 1 or 2,
Wherein the transparent conductive film further comprises at least one optical adjustment layer between the first cured resin layer and the transparent conductive film. 4. The method according to any one of claims 1 to 3,
Wherein the second cured resin layer comprises a resin and particles. 5. The method according to any one of claims 1 to 4,
Wherein the amorphous resin is a cycloolefin resin, the thickness is 20 to 75 占 퐉, the glass transition temperature is 130 占 폚 or more, and the transparent conductive film has a heat of 130 占 폚 for 90 minutes And a shrinkage percentage in the MD and TD directions of less than 0.2%. 6. The method according to any one of claims 1 to 5,
Wherein the optical adjustment layer comprises a binder resin and fine particles, the refractive index is 1.6 to 1.8, and the thickness is 40 to 150 nm. 7. The method according to any one of claims 1 to 6,
The transparent conductive film is made of an indium-tin complex oxide and has a thickness of 10 to 35 nm. A transparent conductive film laminate according to any one of claims 1 to 7, wherein a glass substrate is laminated via a pressure-sensitive adhesive layer on the side opposite to the transparent conductive film. A transparent conductive film laminate according to claim 8 was cut to 210 mm x 260 mm, and the difference (A - A) between the average curl value A at the four corner portions and the curl value B at the center portion after the transparent conductive film was heated to 130 deg. B) is 2.0 mm or less. A touch panel obtained by using the transparent conductive film laminate according to claim 8 or 9.

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