JP6470040B2 - Transparent conductive film, transparent conductive film laminate, and touch panel - Google Patents

Description

  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 the occurrence of curling.

  Conventionally, as substrates for liquid crystal displays, organic electroluminescence displays, touch panels, etc., glass substrates are often used. In recent years, with the thinning of displays, the thinning of glass substrates with excellent transparency, surface smoothness, heat resistance, and the like has attracted attention.

  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 a PET film is stretched and has a high retardation, it is difficult to use it under a polarizing plate. Therefore, Patent Document 1 proposes a transparent conductive film using a cycloolefin-based resin that is an amorphous resin as a low retardation substrate film.

  Patent Document 2 discloses a transparent conductive film in which a transparent conductive film is formed on a polycarbonate or an amorphous polyolefin film as a λ / 4 retardation film that can be used under a polarizing plate such as a liquid crystal display. A laminate in which a transparent conductive film is laminated on a glass substrate, and a liquid crystal display device in which a touch panel function is provided on the entire surface of a flexible cover glass have been proposed.

  When a transparent conductive film is bonded to a thin glass substrate to form a transparent conductive film laminate, the transparent conductive film is crystallized or metal wiring processing for frame wiring is performed at 130 ° C. or higher. It often goes through a heating process. In such a case, since the glass substrate is thin, it is easily affected by heating, and because the thermal shrinkage rate differs between resin and glass, the laminate curls and cannot be transferred to the next process, or alignment of metal wiring Adjustment becomes difficult and metal wiring cannot be processed, making it difficult to carry out stable and continuous production.

JP 2013-114344 A JP 2014-137427 A

  Accordingly, an object of the present invention is to provide a transparent conductive film laminate in which a thin glass substrate is bonded to a transparent conductive film, which can suppress the occurrence of curling even after the heating process and can secure the subsequent process yield. It is providing a conductive film, a transparent conductive film laminated body, and a touch panel.

  As a result of intensive studies to solve the above problems, the present inventors curled in a concave direction when the transparent conductive film laminate had the transparent conductive film up, so the transparent conductive film of the transparent conductive film was placed below. In this case, the inventors have found that the above object can be achieved by designing the transparent conductive film so as to curl in a large concave direction in advance.

  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 surface side of the transparent resin film, and the second surface side of the transparent resin film is second. The transparent resin film is formed of an amorphous resin, and the transparent conductive film is cut into 50 cm × 50 cm, with the transparent conductive film as the bottom surface and 130 ° C. A difference between the average curl value A at the four corners and the curl value B at the center after heating for 90 minutes at (A-B) is a transparent conductive film having a thickness of 5 mm or more. In addition, unless otherwise indicated, the various physical property values in the present invention are values measured by the methods employed in Examples and the like.

  The amorphous resin that forms the transparent resin film is generally formed through an extrusion process or a cast film forming process, and a residual stress always remains, and a shrinkage stress is generated by heating. On the other hand, thin glass has an overwhelmingly small shrinkage stress when heated to about 130 ° C. Therefore, in a transparent conductive film laminate in which thin glass is bonded to a transparent conductive film, curling occurs in the concave direction when heated with the transparent conductive film facing up. Moreover, in a transparent conductive film, since the thermal contraction rate, the linear expansion coefficient, etc. of a transparent conductive film which is an inorganic substance and a transparent resin film which is an organic substance are different, curling due to heating occurs. Therefore, in the present invention, when the transparent conductive film of the transparent conductive film is placed downward, it is designed so as to curl in a large concave direction in advance, so that in the transparent conductive film laminate bonded with thin glass, after the heating step. It was found that the occurrence of curling can be made extremely small. That is, the difference between the average curl value A at the four corners and the curl value B at the center (A− after cutting the transparent conductive film into 50 cm × 50 cm, heating the transparent conductive film on the bottom surface at 130 ° C. for 90 minutes) By setting B) to 5 mm or more, it is possible to counteract the shrinkage force that would have occurred in the laminate laminated on the conventional glass substrate and the shrinkage force that has occurred in the transparent conductive film, and a thin glass In the transparent conductive film laminate after being bonded to the substrate, the curl after the heating step can be made extremely small. As a result, curling after heating due to crystallization of the transparent conductive film, metal wiring processing, or the like can be suppressed, processing and conveyance can be performed stably and continuously, and 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 μm or less, and the thickness of the second cured resin layer is the first thickness. The thickness of the cured resin layer 1 is preferably equal to or thinner than that. When the thickness of the first cured resin layer and the thickness of the second cured resin layer are in the thin range as described above, the influence of the shrinkage force due to the cured resin layer can be reduced, and the transparent resin film It becomes easy to be affected by heating, and curl is more likely to occur. Further, if the thickness of the second cured resin layer is the same as or thinner than the thickness of the first cured resin layer, the transparent resin film is more easily affected by heating, and curling is more likely to occur. A transparent conductive film can be designed.

The transparent conductive film of the present invention preferably further comprises one or more optical adjustment layers between the first cured resin layer and the transparent conductive film. Since the refractive index can be controlled by the optical adjustment layer, even when the transparent conductive film is patterned, the difference in reflectance between the pattern forming portion and the pattern opening can be reduced, the transparent conductive film pattern is difficult to see, and the touch panel, etc. Visibility is improved in the display device.
By passing the annealing process through the film after applying the optical adjustment layer, it is transparent so that the curl amount is more likely to occur by adjusting the thermal contraction difference of the base material in the MD direction and the TD direction and reducing the shrinkage force of the base material. Conductive films can be designed.

  It is preferable that the 2nd cured resin layer in this invention contains resin and particle | grains. Thereby, the anti-blocking property which can endure a roll to roll manufacturing method can be implement | achieved more reliably, and conveyance ease can be improved.

  In the transparent resin film in the present invention, the amorphous resin is a cycloolefin resin, the thickness is 20 to 75 μm, the glass transition temperature is 130 ° C. or higher, and in the transparent conductive film, the temperature is 130 ° C. for 90 minutes. It is preferable that the heat shrinkage ratio after heating is 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 designed so as to be more easily affected by heating and to easily cause curling. In addition, by using a cycloolefin resin having a high glass transition temperature and using a transparent conductive film having a low heat shrinkage rate, excessive heat shrinkage after the heating step can be suppressed, and curling at a higher level can be achieved. You can control the occurrence.

  The optical adjustment layer in the present invention contains a binder resin and fine particles, preferably 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 adjustment layer, the refractive index of the optical adjustment layer itself can be easily adjusted. Moreover, by setting the thickness of the optical adjustment layer in the above range, it is easy to form a continuous film, and it is possible to ensure transparency and control so as not to greatly affect the curling.

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

  It is preferable that the transparent conductive film laminated body of this invention is a transparent conductive film laminated body which laminated | stacked the glass substrate through the adhesive layer on the surface side opposite to the transparent conductive film of the said transparent conductive film. Since the transparent conductive film of the present invention is designed so as to curl in a large concave direction in advance when the transparent conductive film is on the bottom, the transparent conductive film laminated body laminated with thin glass has a curl after the heating step. Generation can be suppressed, and the subsequent process yield can be secured.

  The difference between the average curl value A at the four corners and the curl value B at the center after the transparent conductive film laminate of the present invention was cut into 210 mm × 260 mm and the transparent conductive film was the top surface and heated at 130 ° C. for 90 minutes. (A-B) is preferably 2.0 mm or less. As a result, the occurrence of curling can be suppressed even after the heating step, and the subsequent process yield can be secured.

  The touch panel of the present invention is preferably obtained using the transparent conductive film laminate. When the transparent conductive film laminate is used, curling after a heating step such as drying can be suppressed, so that processing and conveyance of the transparent conductive film laminate is facilitated, and work efficiency is improved.

It is typical sectional drawing of the transparent conductive film which concerns on one Embodiment of this invention. It is typical sectional drawing of the transparent conductive film which concerns on other embodiment of this invention. It is a typical sectional view of the transparent conductive film layered product concerning one 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, parts unnecessary for the description are omitted, and there are parts shown enlarged or reduced for easy explanation. The terms indicating the positional relationship such as up and down are merely used for ease of explanation, and are not intended to limit the configuration of the present invention.

<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, and FIG. 2 is a cross-sectional view schematically showing another embodiment of the transparent conductive film of the present invention. FIG. 3 is a cross-sectional view schematically showing one embodiment of the transparent conductive film laminate of the present invention. The transparent conductive film 10 shown in FIGS. 1-2 has a first cured resin layer 2 and a transparent conductive film 3 formed in this order on one surface side of the transparent resin film 1, and the other of the transparent resin film 1. A second cured resin layer 4 is formed on the surface side. As shown in FIG. 2, one optical adjustment layer 5 can be further provided between the first cured resin layer 2 and the transparent conductive film 3, but two or more optical adjustment layers 5 are provided. You can also. The 1st cured resin layer 2 and the 2nd cured resin layer 4 include what functions as an antiblocking layer or a hard-coat layer. Moreover, as shown in FIG. 3, the transparent conductive film laminated body laminates the glass substrate 6 through the adhesive layer 7 on the surface side opposite to the transparent conductive film 3 of the transparent conductive film 10.

<Transparent conductive film>
In the transparent conductive film, a first cured resin layer and a transparent conductive film are formed in this order on one surface side of the transparent resin film, and a second cured resin layer is formed on the other surface side of the transparent resin film. Is formed. One or more optical adjustment layers may be further included between the first cured resin layer and the transparent conductive film. In the transparent conductive film, the thermal shrinkage in the MD and TD directions when heated at 130 ° C. for 90 minutes is preferably less than 0.2%, more preferably 0.2% or less, and 0 More preferably, it is 15% or less, and particularly preferably 0.1% or less. The lower limit is not particularly limited, but is preferably 0.01% or more. Thereby, it becomes a transparent conductive film excellent in processability, transparency, and the like, and the amount and direction of curling after a heating process such as drying can be controlled, so that the transparent conductive film laminate can be easily processed and conveyed.

  The difference between the average curl value A at the four corners and the curl value B at the center after cutting the transparent conductive film into 50 cm × 50 cm and heating the transparent conductive film on the bottom surface at 130 ° C. for 90 minutes (AB) Is preferably 5 mm or more, more preferably 8 mm or more, and still more preferably 10 mm or more. The upper limit is not particularly limited, but is preferably 50 mm or less, more preferably 40 mm or less, and still more preferably 30 mm or less. When the curl amount of the transparent conductive film is set to be large as described above, the curl after the heating step can be extremely reduced in the transparent conductive film laminate after being bonded to the thin glass substrate. As a result, curling after heating due to crystallization of the transparent conductive film, metal wiring processing, or the like can be suppressed, processing and conveyance can be performed stably and continuously, and subsequent process yield can be ensured.

(Transparent resin film)
The transparent resin film is formed of an amorphous resin and has high transparency and low water absorption characteristics. By adopting the amorphous resin, the optical characteristics of the transparent conductive film can be controlled. The amorphous resin is not particularly limited, but is preferably excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, and the like. Polycarbonate, cycloolefin, polyvinyl chloride, Acrylic resins such as polymethyl methacrylate, polystyrene, polymethyl methacrylate styrene copolymer, polyacrylonitrile, polyacrylonitrile styrene copolymer, high impact polystyrene (HIPS), acrylonitrile butadiene styrene copolymer (ABS resin), poly Examples include arylate, polysulfone, polyethersulfone, and polyphenylene ether. From the viewpoints of high transparency, low water absorption, heat resistance, etc., cycloolefin resins and polycarbonate resins are preferred.

  The cycloolefin resin is not particularly limited as long as it is a resin having a monomer unit composed of a cyclic olefin (cycloolefin). The cycloolefin resin used for the transparent resin film may be either a cycloolefin polymer (COP) or a cycloolefin copolymer (COC). 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 cyclic olefin and a monocyclic cyclic olefin. Such polycyclic olefins include norbornene, methylnorbornene, dimethylnorbornene, ethylnorbornene, ethylidenenorbornene, butylnorbornene, dicyclopentadiene, dihydrodicyclopentadiene, methyldicyclopentadiene, dimethyldicyclopentadiene, tetracyclododecene. , Methyltetracyclododecene, dimethylcyclotetradodecene, tricyclopentadiene, tetracyclopentadiene, and the like. Examples of monocyclic olefins include cyclobutene, cyclopentene, cyclooctene, cyclooctadiene, cyclooctatriene, and cyclododecatriene.

  Cycloolefin-based resins are also available as commercial products, such as “ZEONOR” manufactured by ZEON Corporation, “ARTON” manufactured by JSR, “TOPAS” manufactured by Polyplastics, “APEL” manufactured by Mitsui Chemicals, and the like. It is done.

  The polycarbonate resin is not particularly limited, and examples thereof include aliphatic polycarbonate, aromatic polycarbonate, and aliphatic-aromatic polycarbonate. Specifically, for example, bisphenol A polycarbonate, branched bisphenol A polycarbonate, foamed polycarbonate, copolycarbonate, block copolycarbonate, polyester carbonate, polyphosphonate carbonate, diethylene glycol bisallyl carbonate (CR-) as polycarbonate (PC) using bisphenols 39). Polycarbonate-based resins also include those blended with other components such as bisphenol A polycarbonate blends, polyester blends, ABS blends, polyolefin blends, styrene-maleic anhydride copolymer blends. Examples of commercially available polycarbonate resin include “OPCON” manufactured by Ewa Co., Ltd., “Panlite” manufactured by Teijin Limited, and “Iupilon (UV absorber-containing polycarbonate)” manufactured by Mitsubishi Gas Chemical.

  The transparent resin film is preliminarily subjected to etching treatment such as sputtering, corona discharge, flame, ultraviolet irradiation, electron beam irradiation, chemical conversion, oxidation, and undercoating treatment on the surface, and a cured resin layer formed on the transparent resin film or transparent You may make it improve adhesiveness with an electrically conductive film. In addition, before forming the cured resin layer or the transparent conductive film, the surface of the transparent resin film may be removed 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 μm, more preferably in the range of 25 to 70 μm, and still more preferably in the range of 30 to 65 μm. When the thickness of the transparent resin film is less than the lower limit of the above range, the mechanical strength may be insufficient, and it may be difficult to continuously form a transparent conductive film by rolling the film substrate. 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 dot characteristics for touch panels may not be improved. In addition, when the thickness is within the above range, it is more susceptible to heating, so when the transparent conductive film of the transparent conductive film is placed down, it can be designed to curl in a large concave direction in advance, and thin glass When bonded to form a transparent conductive film laminate, curling after the heating step can be suppressed.

  Although the glass transition temperature (Tg) of the amorphous resin of the said transparent resin film is not specifically limited, 130 degreeC or more is preferable, 150 degreeC or more is more preferable, 160 degreeC or more is still more preferable. Thereby, when it is set as a transparent conductive film laminated body, since generation | occurrence | production of the curl after heating processes, such as drying, can be suppressed, processing conveyance of a transparent conductive film laminated body becomes easy.

  The thermal shrinkage rate in the MD direction and the TD direction when heated at 130 ° C. for 90 minutes at the resin film original fabric (film before applying the heat treatment, etc. before laminating the cured resin layer) forming the transparent resin film, It is preferably 0.3% or less, more preferably 0.2% or less, and further preferably 0.1% or less. Thereby, it becomes a transparent resin film excellent in workability, transparency, dimensional stability during heating, and the like. Moreover, since it can suppress generation | occurrence | production of the curl after heating processes, such as drying, when it is set as a transparent conductive film laminated body, the process conveyance of a transparent conductive film laminated body becomes easy.

  The transparent resin film can be easily a low retardation film having an in-plane retardation (R0) of 0 nm to 10 nm or a λ / 4 film having an in-plane retardation of about 80 nm to 150 nm. When used together, the visibility can be improved. The in-plane retardation (R0) refers to an in-plane retardation value measured at 23 ° 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 surface side of the transparent resin film and a second cured resin layer formed on the other surface side. A transparent resin film formed of an amorphous resin is easily scratched in each process such as formation of a transparent conductive film, patterning of a transparent conductive film, or mounting on an electronic device. A first cured resin layer and a second cured resin layer are formed on both sides of the substrate.

  The cured resin layer is a layer obtained by curing a curable resin. The cured resin layer preferably contains a resin and particles. As the resin to be used, those having sufficient strength as a film after forming the cured resin layer and having transparency can be used without particular limitation, but thermosetting resin, ultraviolet curable resin, electron beam curable resin, two-component Examples thereof include mixed resins. Among these, an ultraviolet curable resin that 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 polyester-based, acrylic-based, urethane-based, amide-based, silicone-based, and epoxy-based resins, and include ultraviolet curable 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, ridges can be formed on the surface of the cured resin layer, and blocking resistance can be suitably imparted to the transparent conductive film.

  As said particle | grains, what has transparency, such as various metal oxides, glass, a plastics, can be especially used without a restriction | limiting. For example, inorganic particles such as silica, alumina, titania, zirconia, calcium oxide, polymethylmethacrylate, polystyrene, polyurethane, acrylic resin, acrylic-styrene copolymer, benzoguanamine, melamine, polycarbonate, or other cross-linked or uncrosslinked polymers. Examples include crosslinked organic particles and silicone particles. The particles can be used by appropriately selecting one type or two or more types, but organic particles are preferable. The organic particles are preferably acrylic resins from the viewpoint of refractive index.

  The mode particle diameter of the particles can be appropriately set in consideration of the degree of protrusion of the cured resin layer and the thickness of a flat region other than the protrusion, and is not particularly limited. In addition, from the viewpoint of sufficiently imparting blocking resistance to the transparent conductive film and sufficiently suppressing increase in haze, the mode particle diameter of the particles is preferably 0.5 to 5 μm. More preferably, it is 0-2 micrometers. In the present specification, “mode particle size” refers to a particle size showing the maximum value of particle distribution, using a flow type particle image analyzer (product name “FPTA-3000S” manufactured by Sysmex). , By measuring under predetermined conditions (Sheath solution: ethyl acetate, measurement mode: HPF measurement, measurement method: total count). The measurement sample is prepared by diluting the particles to 1.0% by weight with ethyl acetate and uniformly dispersing the particles 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 with respect to 100 parts by weight of the resin solid content, and 0.2 to More preferably, it is 0.3 parts by weight. When the content of the particles in the cured resin layer is small, there is a tendency that bulges sufficient to impart blocking resistance and slipperiness to the surface of the cured resin layer are hardly formed. On the other hand, if the content of the particles is too large, the haze of the transparent conductive film increases due to light scattering by the particles, and the visibility tends to decrease. On the other hand, when the content of the particles is too large, streaks are generated during the formation of the cured resin layer (at the time of application of the solution), and the visibility may be impaired, or the electrical characteristics of the transparent conductive film may be uneven. There is a case.

  The cured resin layer is formed by applying a resin composition containing particles, a crosslinking agent, an initiator, a sensitizer and the like to be added to each curable resin as necessary on a transparent resin film, and the resin composition contains a solvent. Is obtained by drying the solvent and curing by application of either heat, active energy rays or both. For the heat, known means such as an air circulation oven or an IR heater can be used, but it is not limited to these methods. Examples of active energy rays include, but are not limited to, ultraviolet rays, electron beams, and gamma rays.

  The cured resin layer can be formed by the wet coating method (coating method) using the above materials. For example, in the case of forming indium oxide (ITO) containing tin oxide as the transparent conductive film, the crystallization time of the transparent conductive film can be shortened if the surface of the cured resin layer that is the base layer is smooth. From this point of view, the cured resin layer is preferably 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 μm or less, more preferably 0.1 μm to 1.5 μm, still more preferably 0.3 μm to 1.2 μm. The thickness of the second cured resin layer is preferably the same as or thinner than the thickness of the first cured resin layer. That is, the thickness of the second cured resin layer is preferably 10 to 100% of the thickness of the first cured resin layer, more preferably 20 to 90%, and more preferably 30 to 80%. Further preferred. Thereby, damage with a transparent resin film can be prevented when it conveys by the roll to roll manufacturing method. Moreover, when the thickness of the cured resin layer is within the above range, it is possible to prevent the visibility of a touch panel and the like from being deteriorated, and when the transparent conductive film of the transparent conductive film is placed downward, it is largely curled in advance in the concave direction. Therefore, curling after the heating step can be suppressed when thin glass is laminated to form a transparent conductive film laminate.

(Transparent conductive film)
The transparent conductive film can be provided on the transparent resin film, but is preferably provided on the first cured resin layer provided on one surface 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. From the group consisting of indium, tin, zinc, gallium, antimony, titanium, silicon, zirconium, magnesium, aluminum, gold, silver, copper, palladium, tungsten A metal oxide of at least one selected metal is preferably used. The metal oxide may further contain a metal atom shown in the above group, if necessary. For example, indium oxide (ITO) containing tin oxide and tin oxide (ATO) containing antimony are preferably used.

The thickness of the transparent conductive film is not particularly limited, but the thickness is preferably 10 to 35 nm in order to obtain a continuous film having good conductivity with a surface resistance of 1 × 10 ³ Ω / □ or less. When the film thickness becomes too thick, the transparency is lowered, and therefore it is more preferably 15 to 35 nm, and still more preferably in the range of 20 to 30 nm. When the thickness of the transparent conductive film is less than 10 nm, the electrical resistance of the film surface increases 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. Further, by forming the transparent conductive film on the first cured resin layer with the above-mentioned thickness, when the transparent conductive film of the transparent conductive film is turned down, it can be designed to curl in a large concave direction in advance.

  The formation method of a transparent conductive film is not specifically limited, A conventionally well-known method is employable. Specific examples include dry processes such as vacuum deposition, sputtering, and ion plating. In addition, an appropriate method can be adopted depending on the required film thickness.

  The transparent conductive film can be crystallized by applying a heat annealing treatment (for example, at 80 to 150 ° C. for about 30 to 90 minutes in an air atmosphere) as necessary. By crystallizing the transparent conductive film, the transparency and durability are improved in addition to the resistance of the transparent conductive film being reduced. The means for converting the amorphous transparent conductive film into crystalline is not particularly limited, and an air circulation oven, an IR heater, or the like is used.

  Regarding the definition of “crystalline”, a transparent conductive film in which a transparent conductive film is formed on a transparent resin film is immersed in hydrochloric acid having a concentration of 5% by weight at 20 ° C. for 15 minutes, then washed with water and dried for 15 mm. When the inter-terminal resistance is measured with a tester and the inter-terminal resistance does not exceed 10 kΩ, it is assumed that the conversion of the ITO film to crystalline is completed. The surface resistance value can be measured by a four-terminal method according to JIS K7194.

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

(Optical adjustment layer)
One or more optical adjustment layers may be further included between the first cured resin layer and the transparent conductive film. The optical adjustment layer increases the transmittance of the transparent conductive film, or when the transparent conductive film is patterned, the transmittance difference or reflectance difference between the pattern part where the pattern remains and the opening part where the pattern does not remain. Is used to obtain a transparent conductive film excellent in visibility.

  The optical adjustment layer preferably contains a binder resin and fine particles. Examples of the binder resin included in the optical adjustment layer include acrylic resins, urethane resins, melamine resins, alkyd resins, siloxane polymers, and organic silane condensates, and ultraviolet curable resins including acrylic resins. preferable.

  The refractive index of the optical adjustment layer is preferably 1.6 to 1.8, more preferably 1.62 to 1.78, and still more preferably 1.65 to 1.75. Thereby, the transmittance | permeability difference and the reflectance difference can be reduced, and the 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 fine particles in the optical adjustment layer is preferably 0.1% by weight to 90% by weight. As described above, the average particle size of the fine particles used in the optical adjustment layer is preferably in the range of 1 nm to 500 nm, and more preferably 5 nm to 300 nm. The content of fine particles in the optical adjustment layer is more preferably 10% by weight to 80% by weight, and further preferably 20% by weight to 70% by weight. By containing fine particles in the optical adjustment layer, the refractive index of the optical adjustment layer itself can be easily adjusted.

  Examples of the inorganic oxide forming the fine particles include fine particles of silicon oxide (silica), hollow nanosilica, titanium oxide, aluminum oxide, zinc oxide, tin oxide, zirconium oxide, niobium oxide, and the like. 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 alone or in combination of two or more.

The optical adjustment layer can contain other inorganic substances. The inorganic _{material, 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), etc. (the numerical values in parentheses indicate the refractive index).

  The optical adjustment layer can be formed by 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 deposition method, a sputtering method, an ion plating method, or the like. For example, in the case where indium oxide (ITO) containing tin oxide is formed as the transparent conductive film, the crystallization time of the transparent conductive layer can be shortened if the surface of the resin layer that is the base layer is smooth. From this point of view, the resin layer is preferably 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 too small, it is difficult to form a continuous film. Moreover, when the thickness of the optical adjustment layer is excessively large, the transparency of the transparent conductive film tends to be reduced or cracks tend to occur.

(Metal wiring)
The metal wiring can be formed by etching after forming the metal layer on the transparent conductive film, but is preferably formed using a photosensitive metal paste as follows. That is, after the transparent conductive film is patterned, the metal wiring is formed by applying a photosensitive conductive paste described later on the transparent resin film or the transparent conductive film, forming a photosensitive metal paste layer, and forming a photomask. The photosensitive metal paste layer is exposed through a photomask after being laminated or brought close to each other, then developed and patterned to obtain a drying process. That is, the metal wiring pattern can be formed by a known photolithography method or the like.

  The photosensitive conductive paste preferably includes conductive particles such as metal powder and a photosensitive organic component. The material of the conductive particles of the metal powder preferably contains at least one 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 μm to 2.5 μm.

  The conductive particles other than the metal powder may be metal-coated resin particles in which the resin particle surfaces are coated with 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 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 size of 0.1 μm to 1.4 μm, a 90% particle size of 1 to 2 μm, and a top size of 4.5 μm or less. As the composition of the glass frit is not particularly limited, Bi ₂ O ₃ is are preferably blended in a range of 30% to 70% by weight relative to the total. Examples of the oxide 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 . Na ₂ O, K ₂ O, and Li ₂ O are preferably alkali-free glass frit that is substantially free of them.

  The photosensitive organic component preferably contains a photosensitive polymer and / or a photosensitive monomer. As the photosensitive polymer, a polymer of a component selected from a compound having a carbon-carbon double bond such as methyl (meth) acrylate, ethyl (meth) acrylate, or a side chain or molecule of an acrylic resin comprising these copolymers. Those having a photoreactive group added to the terminal are preferably used. Preferred photoreactive groups include ethylenically unsaturated groups such as vinyl, allyl, acrylic and methacrylic 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, γ-methacryloxypropyltrimethoxysilane, 1-vinyl-2-pyrrolidone and the like, and one or more are used. can do.

  In the photosensitive conductive paste, the photosensitive organic component is preferably contained in an amount of 5 to 40% by weight with respect to 100 parts by weight of the metal powder in terms of light sensitivity, and more preferably 10 to 30 parts by weight. The photosensitive conductive paste of the present invention preferably uses a photopolymerization initiator, a sensitizer, a polymerization inhibitor, and an organic solvent as necessary.

  The thickness of the metal layer is not particularly limited. For example, when the pattern wiring is formed by removing a part of the surface of the metal layer by etching or the like, 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 μm, and more preferably 0.05 to 100 μm. When the thickness of the metal layer is within the above range, the resistance of the pattern wiring does not become too high, and the power consumption of the device does not increase. In addition, the production efficiency of the metal layer is increased, the integrated heat amount during the film formation is reduced, and the film is less likely to be thermally wrinkled.

  When the transparent conductive film is a transparent conductive film for a touch panel used in combination with a display, the portion corresponding to the display portion is formed by a patterned transparent conductive film, and a metal wiring made from a photosensitive conductive paste Is used for the wiring part of the non-display part (for example, the peripheral part). The transparent conductive film may be used even in a non-display portion, and in that case, 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 via an adhesive layer on the other side of the transparent conductive film of the transparent conductive film. The transparent conductive film laminate is obtained by cutting the transparent conductive film laminate into 210 mm × 260 mm, with the transparent conductive film as the upper surface and heating at 130 ° C. for 90 minutes, and then the average curl value A at the four corners and the curl at the center. The difference (A−B) from the value B is preferably 2.0 mm or less, more preferably less than 2.0 mm, and still more preferably 1.8 mm or less. The lower limit is not particularly limited, but is preferably 0.5 mm or more. When the curl amount is suppressed in this way, when the transparent conductive film laminate is transported, it can be sucked with air and can be continuously processed and transported.

(Glass substrate)
A glass substrate laminates a transparent conductive film through an 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 materials having excellent transparency, surface smoothness, thermal stability, moisture barrier property, isotropy, and the like are preferable, and examples include soda lime glass and borosilicate glass. . These glasses may be chemically strengthened, and an alkali elution preventing layer may be formed on the surface. Moreover, in order to raise the adhesive force with another layer, the glass surface may be processed with the silane coupling agent.

  The thickness of the glass substrate is preferably 0.1 to 1.5 mm, and more preferably 0.3 to 1.0 mm. If the thickness is too thin, the glass tends to be damaged when the transparent conductive film laminate is heated. On the other hand, if the thickness is too thick, it is difficult to make the display thinner and the flexibility is lowered. A glass substrate having a thickness in such a range is bonded to a transparent conductive film designed to curl in a large concave direction in advance when the transparent conductive film is placed downward to produce a transparent conductive film laminate, thereby heating step Later curling can be suppressed.

(Adhesive layer)
As the pressure-sensitive adhesive layer, any of the following pressure-sensitive adhesives can be used as long as it has transparency. Specific examples of the pressure-sensitive adhesive include acrylic polymer, silicone polymer, polyester, polyurethane, polyamide, polyvinyl ether, vinyl acetate / vinyl chloride copolymer, modified polyolefin, epoxy-based, fluorine-based, natural rubber, and synthetic rubber. A polymer having a base polymer such as a rubber-based polymer can be appropriately selected and used. In particular, an acrylic pressure-sensitive adhesive is preferably used from the viewpoint that it is excellent in optical transparency, exhibits adhesive properties such as appropriate wettability, cohesiveness and adhesiveness, and is excellent in weather resistance and heat resistance.

  The method for forming the pressure-sensitive adhesive layer is not particularly limited, and is a method in which the pressure-sensitive adhesive composition is applied to a release liner, dried and transferred to a glass substrate (transfer method), and the pressure-sensitive adhesive composition is directly applied to the glass substrate. Examples include a drying method (direct copying method). In addition, a tackifier, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a silane coupling agent, and the like can be appropriately used as the pressure-sensitive adhesive.

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

<Touch panel>
A transparent conductive film laminated body is suitably applicable as a transparent electrode of electronic devices, such as touch panels, such as a capacitance system and a resistive film system, for example. Moreover, since the transparent conductive film laminated body of this invention has laminated | stacked on the glass substrate, it can apply suitably as a transparent electrode of electronic devices, such as a touchscreen, as it is.

  In forming the touch panel, the above-described transparent conductive film laminate can be used. In this invention, although the laminated body by which the glass substrate was bonded together through the transparent adhesive layer is formed in the surface by which the transparent conductive film of the transparent conductive film is not formed, a glass substrate is one sheet. It may consist of a substrate, or may be a laminate of two or more substrates (for example, laminated via a transparent adhesive layer). As described above, the pressure-sensitive adhesive layer used for bonding the transparent conductive film and the substrate can be used without particular limitation as long as it has transparency.

  When the above transparent conductive film laminate is used to form a touch panel, the amount and direction of curling after a heating step such as drying can be suppressed, so that the transparent conductive film laminate can be easily transported during touch panel formation. Excellent handleability. Therefore, a touch panel excellent in transparency and visibility can be manufactured with high productivity. If it is other than a touch panel use, it can be used for the shield use which shields the electromagnetic waves and noise which are emitted from an electronic device.

<Method for producing transparent conductive film laminate>
The method for producing a transparent conductive film laminate of the present invention includes a step of preparing a transparent conductive film in which an amorphous transparent conductive film is formed on a transparent resin film, and the transparent conductive film of the transparent conductive film is the other The process of laminating | stacking a glass substrate on the surface side of this through an adhesive layer, and the process of heat-processing the said transparent conductive film laminated body are included. As a process of heat-processing a transparent conductive film laminated body, the process of crystallizing a transparent conductive film, the process of drying the metal wiring formed with the photosensitive metal paste layer, etc. are mentioned, for example. The transparent conductive film laminate is preferably subjected to such a heating process. Thereby, since a transparent conductive film is designed so that it may curl greatly in a concave direction beforehand when a transparent conductive film is turned down, generation | occurrence | production of a curl can be suppressed in a transparent conductive film laminated body.

  The transparent conductive film used in the step of preparing the transparent conductive film may form a cured resin layer on the transparent resin film and then form a transparent conductive film, or the cured resin layer may be formed on the transparent resin film. The formed transparent resin laminate may be obtained, and then 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 the transparent resin film. You may obtain it. Also regarding the optical adjustment layer described above, a transparent resin laminate formed in advance may be obtained and used.

  In the step of laminating the glass substrate, an adhesive layer is formed on the release substrate, the adhesive layer is transferred to the glass substrate, and the transparent resin film of the second cured resin layer of the transparent conductive film is not formed. A glass substrate may be laminated on the side through an adhesive layer, or an adhesive layer may be directly formed on the glass substrate. Moreover, an adhesive layer may be formed in the surface opposite to the transparent conductive film of a transparent conductive film, and a glass substrate may be laminated | stacked.

  In order to crystallize the constituent components of the transparent conductive film, it is put into a heat-treated process. The heating temperature is preferably, for example, 130 ° C. or lower, more preferably 120 ° C. or lower, and the treatment time is, for example, 15 to 180 minutes. Then, a transparent conductive film is etched and a pattern part is formed with a pattern. In the present invention, after the transparent conductive film is patterned, the above-mentioned photosensitive conductive paste is applied onto the transparent resin film or the transparent conductive film, a photosensitive metal paste layer is formed, and a photomask is stacked or adjacent. It is preferable to further include a step of exposing the photosensitive metal paste layer through the photomask or obtaining metal wiring by screen printing or the like. The drying step is preferably performed at 130 ° C. or less, and preferably 120 ° C. or less. The heat treatment for crystallizing the transparent conductive film laminate, the subsequent etching process, and the metal wiring process are performed in a single-wafer process because there is alignment of patterning of the photomask, the transparent conductive film, and the metal wiring. At that time, a process of fixing to the suction plate is necessary for alignment, but the amount and direction of curling can be controlled even after drying in the above temperature range. Is possible.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited to a following example, unless the summary is exceeded.

[Example 1]
(Preparation of curable resin composition containing spherical particles)
Acrylic spherical particles (manufactured by Soken Chemical Co., Ltd.) having 100 parts by weight of an ultraviolet curable resin composition (trade name “UNIDIC (registered trademark) RS29-120” manufactured by DIC) and a mode particle diameter of 1.9 μm. A curable resin composition containing spherical particles containing 0.3 part by weight of “MX-180TA”) was prepared.

(Formation of cured resin layer)
The prepared spherical particle-containing curable resin composition is applied to one surface of a polycycloolefin film (trade name “ZEONOR (registered trademark)” manufactured by Nippon Zeon Co., Ltd.) having a thickness of 35 μm and a glass transition temperature of 165 ° C. Formed. Next, the coating layer was irradiated with ultraviolet rays from the side on which the coating layer was formed, and a second cured resin layer was formed so as to have a thickness of 1.0 μm. A first cured resin layer was formed on the other surface of the polycycloolefin film by the same method except that spherical particles were not added, so that the thickness was 1.0 μm.

(Formation of optical adjustment layer)
A zirconia particle-containing ultraviolet curable composition having a refractive index of 1.62 as an optical adjustment layer on the first cured resin layer side of the polycycloolefin film having cured resin layers formed on both sides (trade name “OPSTA Z7412 manufactured by JSR Corporation”). Was applied to form a coating layer. Then, the coating layer was irradiated with ultraviolet rays from the side where the coating layer was formed, and an optical adjustment layer was formed so that the thickness was 100 nm.

(Formation of transparent conductive film)
Next, the polycycloolefin film on which the optical adjustment layer is formed is put into a take-up sputtering apparatus, and an amorphous indium tin oxide layer (composition: SnO) having a thickness of 27 nm is formed on the surface of the optical adjustment layer. ₂ 10 wt%) to form a transparent conductive film. In this way, a transparent conductive film was produced.

(Formation of transparent conductive film laminate)
By normal solution polymerization, an acrylic polymer having a weight average molecular weight of 600,000 was obtained with butyl acrylate / acrylic acid = 100/6 (weight ratio). An acrylic pressure-sensitive adhesive was prepared by adding 6 parts by weight of an epoxy-based crosslinking agent (trade name “Tetrad C (registered trademark)” manufactured by Mitsubishi Gas Chemical) to 100 parts by weight of the acrylic polymer. After applying the acrylic pressure-sensitive adhesive obtained as described above on a thin soda glass having a thickness of 0.4 mm and cut to 210 mm × 260 mm (thickness after drying: 20 μm), the transparent conductive film is on top A transparent conductive film laminate was prepared by laminating a transparent conductive film.

[Example 2]
In 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, and the frequency of spherical particles contained in the second cured resin layer A transparent conductive film and a transparent conductive film laminate were prepared in the same manner as in Example 1, except that a particle having a particle diameter of 0.8 μm was used and the thickness of the second cured resin layer was 0.5 μm. The body was made.

[Example 3]
In Example 1, the transparent conductive film and the transparent film were formed in the same manner as in Example 1 except that after forming the optical adjustment layer, the film was annealed at 150 ° C. for 3 minutes by the roll-to-roll manufacturing method, and then the transparent conductive film was formed. A conductive film laminate was formed.

[Example 4]
In Example 1, a transparent conductive film was prepared in the same manner as in Example 1 except that a polycycloolefin film having a thickness of 50 μm (trade name “ZEONOR (registered trademark)” manufactured by Nippon Zeon Co., Ltd.) was used as the transparent resin film. And the transparent conductive film laminated body was produced.

[Example 5]
In Example 3, a transparent conductive film was prepared in the same manner as in Example 3 except that a polycycloolefin film having a thickness of 50 μm (trade name “ZEONOR (registered trademark)” manufactured by Nippon Zeon Co., Ltd.) was used as the transparent resin film. And the transparent conductive film laminated body was produced.

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

[Comparative Example 2]
In Example 1, a transparent conductive film was prepared in the same manner as in Example 1 except that a 75 μm thick polycycloolefin film (trade name “ZEONOR (registered trademark)” manufactured by Nippon Zeon Co., Ltd.) was used as the transparent resin film. And the transparent conductive film laminated body was produced.

[Comparative Example 3]
Example 1 except that polyester resin (PET) (trade name “Diafoil (registered trademark)” manufactured by Mitsubishi Plastics) having a thickness of 50 μm and a glass transition temperature of 70 ° C. was used as the transparent resin film in Example 1. A transparent conductive film and a transparent conductive film laminate were produced in the same manner as described above.

<Evaluation>
(1) Measurement of thickness Thickness was measured with a micro gauge thickness meter (Mitutoyo Co., Ltd.) for those having a thickness of 1 μm or more. The thickness of less than 1 μm and the thickness of the optical adjustment layer (100 nm) were measured with an instantaneous multi-photometry system (MCPD2000 manufactured by Otsuka Electronics Co., Ltd.). For nano-sized thickness like the thickness of ITO film etc., FB-2000A (manufactured by Hitachi High-Technologies Co., Ltd.) is used to prepare a sample for cross-sectional observation, and cross-sectional TEM observation is HF-2000 (manufactured by Hitachi High-Technologies Corporation) Was used to measure the film thickness. The evaluation results are shown in Table 1.

(2) Measurement of curl value in transparent conductive film The transparent conductive films obtained in Examples and Comparative Examples were cut into 50 cm × 50 cm sizes. After heating at 130 ° C. for 90 minutes with the ITO surface facing down, it was allowed to cool at room temperature (23 ° C.) for 1 hour. Thereafter, the sample was placed on a horizontal surface with the ITO surface down, and the heights from the horizontal surfaces at the four corners were measured, and the average value (curl value A) was calculated. Moreover, the height (curl value B) from the horizontal surface of the center part was measured. A value (A−B) obtained by subtracting the curl value B from the curl value A was calculated as the curl amount. The evaluation results are shown in Table 1.

(3) Measurement of curl value in transparent conductive film laminate The transparent conductive film laminate obtained in Examples and Comparative Examples was cut into a size of 210 mm × 260 mm × 0.4 mm. After heating at 130 ° C. for 90 minutes with the ITO surface facing up, it was allowed to cool at room temperature (23 ° C.) for 1 hour. Thereafter, the sample was placed on a horizontal surface with the ITO surface facing upward, the heights from the horizontal surfaces at the four corners were measured, and the average value (curl value A) was calculated. Moreover, the height (curl value B) from the horizontal surface of the center part was measured. A value (A−B) obtained by subtracting the curl value B from the curl value A was calculated as the curl amount. The evaluation results are shown in Table 1.

(4) Thermal contraction rate in MD direction and TD direction The thermal contraction rate in the longitudinal direction (MD direction) and the width direction (TD direction) of the transparent conductive film was calculated as follows. Specifically, the transparent conductive film is cut to a width of 100 mm and a length of 100 mm (test piece), and the four corners are scratched with a cross, and the length before heating in the MD direction and the TD direction at the four central parts of the cross scratch The thickness (mm) was measured with a CNC three-dimensional measuring machine (LEGEX 774 manufactured by Mitutoyo Corporation). Then, it put into oven and heat-processed (130 degreeC, 90 minutes). After allowing to cool at room temperature for 1 hour, measure the length (mm) of the four corners after heating in the MD and TD directions with a CNC coordinate measuring machine and assign the measured value to the following equation. The thermal shrinkage rates in the MD direction and the TD direction were determined. The evaluation results are shown in Table 1.
Thermal contraction rate (%) = [[length before heating (mm) −length after heating (mm)] / length before heating (mm)] × 100

(5) Measurement of glass transition temperature (Tg) Glass transition temperature (Tg) was calculated | required based on prescription | regulation of JISK7121.

(Results and discussion)
In the transparent conductive films of Examples 1 to 5, the direction of curl generation was a concave direction when the transparent conductive film was placed downward, and the curl generation amount was as large as 7 to 28 mm. Therefore, the transparent conductive film laminate Then, the direction of curl generation was a concave direction when the transparent conductive film was on top, and the curl generation amount was 1.1 to 2.0 mm. Moreover, in the transparent conductive film of Comparative Examples 1-2, since the direction of curl generation was a concave direction when the transparent conductive film was down, and the amount of curl generation was as small as 2-4 mm, in the transparent conductive film laminate, When the transparent conductive film was placed on top, the direction was concave, and the amount of curling was greatly curled to 2.5 to 4.3 mm. From the above, there is a correlation between the curl amount of the transparent conductive film and the warp after the transparent conductive film laminate, and when a curl amount of 5 mm or more is generated in the transparent conductive film, It has been found that the curl amount of can be reduced. In addition, although the comparative example 3 is a value which does not have a problem as a curl value, since the PET film is used for a base material and there is a high phase difference, it cannot be used as a base material under a polarizing plate.

DESCRIPTION OF SYMBOLS 1 Transparent resin film 2 1st cured resin layer 3 Transparent electrically conductive film 4 2nd cured resin layer 5 Optical adjustment layer 6 Glass substrate 7 Adhesive layer 10 Transparent conductive film

Claims (9)

A first cured resin layer, an optical adjustment layer, and a transparent conductive film are formed in this order on one surface side of the transparent resin film, and a second cured resin layer is formed on the other surface side of the transparent resin film. A transparent conductive film,
The transparent resin film is made of an amorphous resin,
The difference between the average curl value A at the four corners and the curl value B at the central part after the transparent conductive film was cut into 50 cm × 50 cm and the transparent conductive film was the bottom surface and heated at 130 ° C. for 90 minutes (AB) ) Is 5 mm or more,
The optical adjustment layer is a transparent conductive film containing a binder resin and fine particles, having a refractive index of 1.6 to 1.8, and a thickness of 40 to 150 nm .   The thickness of the first cured resin layer and the thickness of the second cured resin layer are both 2 μm or less, and the thickness of the second cured resin layer is the same as the thickness of the first cured resin layer. The transparent conductive film according to claim 1, which is thinner.   The transparent conductive film according to claim 1, further comprising one or more optical adjustment layers between the first cured resin layer and the transparent conductive film.   The transparent conductive film according to claim 1, wherein the second cured resin layer includes a resin and particles.   In the transparent resin film, the amorphous resin is a cycloolefin resin, the thickness is 20 to 75 μm, the glass transition temperature is 130 ° C. or higher, and the transparent conductive film is heated at 130 ° C. for 90 minutes. The transparent conductive film according to any one of claims 1 to 4, wherein the heat shrinkage rate after the treatment is less than 0.2% in the MD and TD directions. The transparent conductive film according to claim 1 , wherein the transparent conductive film is made of an indium-tin composite oxide and has a thickness of 10 to 35 nm. The transparent conductive film laminated body which laminated | stacked the glass substrate through the adhesive layer on the surface side opposite to the transparent conductive film of the transparent conductive film of any one of Claims 1-6 . The transparent conductive film laminate according to claim 7 is cut into 210 mm × 260 mm, and the transparent conductive film is used as an upper surface, and after heating at 130 ° C. for 90 minutes, the average curl value A at the four corners and the curl value B at the central part The transparent conductive film laminated body whose difference (AB) is 2.0 mm or less. A touch panel obtained using the transparent conductive film laminate according to claim 7 .

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