KR102021215B1 - Transparent conductive film, transparent conductive film laminate, and touch panel - Google Patents

Abstract

In the transparent conductive film laminated body which bonded the thin glass substrate to the transparent conductive film, the generation | occurrence | production of a curl can be suppressed after a heating process, and the transparent conductive film which can ensure a subsequent process yield, a transparent conductive film laminated body, and a touch panel To provide.
As for the transparent conductive film 10 in this invention, the 1st cured resin layer 2 and the transparent conductive film 3 are formed in this order in one surface side of the transparent resin film 1, and a transparent resin film As the transparent conductive film 10 in which the 2nd cured resin layer 4 was formed in the other surface side of (1), the transparent resin film 1 consists of amorphous resins, and makes the transparent conductive film 10 50 cm It is transparent at which the difference (A-B) between the average curl value A of the four corner parts and the curl value B of the center part is 5 mm or more after cutting to x 50 cm and heating at 130 degreeC for 90 minutes making the transparent conductive film 3 into a lower surface. Film 10.

Description

Transparent conductive film, transparent conductive film laminated body, and touch panel {TRANSPARENT CONDUCTIVE FILM, TRANSPARENT CONDUCTIVE FILM LAMINATE, AND TOUCH PANEL}

This invention relates to a transparent conductive film, a transparent conductive film laminated body, and a touch panel, and is a technique especially useful for generation | occurrence | production control of a curl.

Conventionally, as substrates, such as a liquid crystal display, an organic electroluminescent display, and a touch panel, what used glass as a board | substrate has been used a lot. In recent years, with the thinning of a display, thinning in the glass substrate excellent in transparency, surface smoothness, heat resistance, etc. attracts attention.

On the other hand, in the 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 phase difference, it is difficult to use it as a basis of a polarizing plate. Therefore, in patent document 1, the transparent conductive film using cycloolefin resin which is amorphous resin as a base film for low phase difference is proposed.

In patent document 2, as a (lambda) / 4 phase (s) difference film which can be used under polarizing plates, such as a liquid crystal display, the transparent conductive film which provided the transparent conductive film on the polycarbonate and amorphous polyolefin film is disclosed, and this transparent conductive film is BACKGROUND ART A liquid crystal display device in which a touch panel function has been imparted to a laminated body laminated on a glass substrate and a full surface flexible cover glass is proposed.

After bonding a transparent conductive film to a thin glass substrate and making it a transparent conductive film laminated body, when performing a crystallization of a transparent conductive film or performing metal wiring processing for frame wiring, the heating process of 130 degreeC or more is performed. Often via. In this case, since the glass substrate is thin, it is easy to be affected by heating, and the heat shrinkage ratio of the resin and glass is different, so that the laminate is curled and cannot be transferred to the next step, or the alignment of the metal wiring is difficult to be adjusted. It is not possible to process and it is difficult to carry out a stable and continuous production.

Japanese Unexamined Patent Publication No. 2013-114344 Japanese Unexamined Patent Publication No. 2014-137427

Then, the objective of this invention is the transparent conductive film laminated body which bonded the thin glass substrate to the transparent conductive film WHEREIN: The transparent conductive film which can suppress generation | occurrence | production of a curl after a heating process, and can secure a subsequent process yield, It is providing a transparent conductive film laminated body and a touch panel.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, when the transparent conductive film laminated body curled largely in the concave direction when the transparent conductive film was up, the concave direction beforehand is large when the transparent conductive film of the transparent conductive film is down. By designing a transparent conductive film so that it may curl, it discovered that the said objective can be achieved and came to this invention.

That is, in the transparent conductive film of this invention, a 1st cured resin layer and a transparent conductive film are formed in this order in one surface side of a transparent resin film, and the 2nd cured resin layer was formed in the other surface side of the said transparent resin film. As a transparent conductive film, the said transparent resin film consists of amorphous resin, cuts the said transparent conductive film into 50 cm x 50 cm, and makes the transparent conductive film into the lower surface, and averages the four corner parts after heating at 130 degreeC for 90 minutes. The difference (A-B) between curl value A and curl value B in the center portion is a transparent conductive film having a thickness of 5 mm or more. In addition, the various physical property values in this invention are a value measured by the method employ | adopted in an Example etc. unless there is particular notice.

Generally, the amorphous resin which forms a transparent resin film is formed into a film | membrane through an extrusion process or a cast film forming process, and a residual stress always remains and a shrinkage stress arises by heating. On the other hand, thin glass is predominantly small in shrinkage stress in the heating at about 130 degreeC. Therefore, in the transparent conductive film laminated body which bonded thin glass to the transparent conductive film, curling generate | occur | produces in the concave direction when the transparent conductive film is heated up. Moreover, in a transparent conductive film, since the thermal contraction rate, linear expansion coefficient, etc. of a transparent conductive film which is an inorganic substance, and the transparent resin film which is an organic substance differ, the curl by heating generate | occur | produces. Therefore, in this invention, when the transparent conductive film of a transparent conductive film is made down, it is designed so that it may curl in large concave direction previously, and generation | occurrence | production of the curl after a heating process can be made very small in the transparent conductive film laminated body which bonded thin glass. I found out. That is, the difference (A-B) between the average curl value A of the four corner parts and the curl value B of the center part after cutting a transparent conductive film into 50 cm x 50 cm, and heating at 130 degreeC for 90 minutes making a transparent conductive film into a lower surface, 5 By setting it as mm or more, the shrinkage force which may have arisen in the laminated body laminated | stacked on the conventional glass substrate, and the shrinkage force which arisen in the transparent conductive film can be offset, and a heating process in the transparent conductive film laminated body after pasting together with a thin glass substrate The later curl can be made very small. Thereby, the curl after heating by crystallization of a transparent conductive film, metal wiring work, etc. can be suppressed, processing and conveyance can be carried out stably and continuously, and the subsequent process yield can be ensured.

In the transparent conductive film of this invention, the thickness of the said 1st cured resin layer and the thickness of the said 2nd cured resin layer are all 2 micrometers or less, and the thickness of the said 2nd cured resin layer is a thing of the said 1st cured resin layer It is preferred to be equal to or thinner than the thickness. If the thickness of a 1st cured resin layer and the thickness of a 2nd cured resin layer are a thin range as mentioned above, the influence of the shrinkage force resulting from a cured resin layer can be made small, and a transparent resin film will be easy to be influenced at the time of a heating. Curls are more likely to occur. Moreover, when the thickness of a 2nd cured resin layer is equal to or thinner than the thickness of the said 1st cured resin layer, a transparent conductive film will become more susceptible at the time of a heating, and a curl will be more likely to generate | occur | produce. Can be designed.

It is preferable that the transparent conductive film of this invention is equipped with one or more optical adjustment layers further between the said 1st cured resin layer and the said 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 portion can be reduced, and the transparent conductive film pattern is hard to be seen. The visibility becomes good in.

By passing an annealing process to a film after coating an optical adjustment layer, a transparent conductive film can be designed so that curl amount may become more likely to occur by adjusting the base material heat shrinkage difference of MD direction and a TD direction, and reducing shrinkage force of a base material.

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 the roll-to-roll manufacturing method can be realized more reliably, and conveyance easiness can be improved.

In the transparent resin film of 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, 90 minutes at 130 ° C. It is preferable that the thermal contraction rate after heating is less than 0.2% in MD and TD directions. Since the thickness of a transparent resin film exists in the comparatively thin range, a transparent conductive film can be designed so that it may be easy to be influenced at the time of heating, and to generate curl easily. Moreover, by using cycloolefin resin with a high glass transition temperature and using a transparent conductive film with a small thermal contraction rate, excess thermal contraction after a heating process can be suppressed and generation | occurrence | production of a curl can be controlled at a higher level. .

It is preferable that the optical adjustment layer in this invention contains binder resin and microparticles | fine-particles, refractive index is 1.6-1.8, and thickness is 40-150 nm. By including microparticles | fine-particles in an optical adjusting layer, refractive index adjustment of an optical adjusting layer itself can be performed easily. Moreover, by making thickness of an optical adjustment layer into the said range, it becomes easy to become a continuous film, transparency can be ensured, and it can control so that it does not have a big influence on curl generation.

It is preferable that the transparent conductive film in this invention consists of indium tin composite oxide (ITO), and whose thickness is 10-35 nm. Thereby, transparency can be ensured, visibility can be improved also when using a touch panel etc., and the direction and quantity of curl generation 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 this invention is designed so that it may curl in large concave direction beforehand when a transparent conductive film is made down, in the transparent conductive film laminated body which bonded thin glass, generation | occurrence | production of the curl after a heating process can be suppressed, and The subsequent process yield can be secured.

The difference between the average curl value A of the four corner parts and the curl value B of the center part after cutting the transparent conductive film laminated body of this invention to 210 mm x 260 mm, and heating at 130 degreeC for 90 minutes using a transparent conductive film as an upper surface (A-B) It is preferable that it is 2.0 mm or less. Thereby, generation | occurrence | production of a curl can be suppressed also after a heating process, and the subsequent process yield can be ensured.

It is preferable that the touchscreen of this invention is obtained using the said transparent conductive film laminated body. When the said transparent conductive film laminated body is used, curl generation after a heating process, such as drying, can be suppressed, and the process conveyance of a transparent conductive film laminated body becomes easy, and work efficiency improves.

BRIEF DESCRIPTION OF THE DRAWINGS 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 typical sectional drawing of the transparent conductive film laminated body which concerns on one Embodiment of this invention.

Embodiment of the transparent conductive film laminated body of this invention is described below, referring drawings. However, in some or all of the drawings, parts unnecessary for the description are omitted, and there are parts shown to be enlarged or reduced in order to facilitate explanation. Terms indicating positional relations such as up and down are merely used to facilitate explanation, and there is no intention to limit the configuration of the present invention.

<Structure of Transparent Conductive Film and Laminate>

FIG. 1: is sectional drawing which shows one Embodiment of the transparent conductive film of this invention typically, FIG. 2 is sectional drawing which shows another embodiment of the transparent conductive film of this invention typically, FIG. 3 is this invention It is sectional drawing which shows typically one Embodiment of the transparent conductive film laminated body. In the transparent conductive film 10 shown to FIGS. 1-2, the 1st cured resin layer 2 and the transparent conductive film 3 are formed in this order in one surface side of the transparent resin film 1, and the said transparent The second cured resin layer 4 is formed on the other surface side of the resin film 1. As shown in FIG. 2, although the optical adjustment layer 5 of one layer can be further provided between the said 1st cured resin layer 2 and the said transparent conductive film 3, two or more optical adjustment layers ( 5) may be provided. The 1st cured resin layer 2 and the 2nd cured resin layer 4 contain what functions as an anti blocking layer and a hard-coat layer. Moreover, as shown in FIG. 3, the transparent conductive film laminated body laminates the glass substrate 6 via the adhesive layer 7 on the surface side opposite to the transparent conductive film 3 of the transparent conductive film 10. Moreover, as shown in FIG. do.

<Transparent conductive film>

As for a transparent conductive film, a 1st cured resin layer and a transparent conductive film are formed in this order in one surface side of a transparent resin film, and the 2nd cured resin layer is formed in the other surface side of the said transparent resin film. One or more optical adjusting layers may be further included between the first cured resin layer and the transparent conductive film. In the transparent conductive film, the heat shrinkage in the MD direction and the TD direction when heated at 130 ° C. for 90 minutes is preferably 0.2% or less, more preferably less than 0.2%, still more preferably 0.15% or less, and 0.1% It is especially preferable that it is the following. The lower limit is not particularly limited, but is preferably 0.01% or more. Thereby, since it becomes a transparent conductive film excellent in workability, transparency, etc., and can generate | occur | produce the amount and direction of curl after a heating process, such as drying, process conveyance of a transparent conductive film laminated body becomes easy.

The difference (A-B) between the average curl value A of the four corner parts and the curl value B of the center part is 5 mm or more after cut | disconnecting a transparent conductive film at 50 cm x 50 cm, and making a transparent conductive film into a lower surface, and heating at 130 degreeC for 90 minutes. It is preferable, it is more preferable that it is 8 mm or more, and it is still more preferable that it is 10 mm or more. Although an upper limit in particular is not restrict | limited, It is preferable that it is 50 mm or less, It is more preferable that it is 40 mm or less, It is further more preferable that it is 30 mm or less. Thus, when the curl amount of a transparent conductive film is set large, the curl after a heating process can be made very small in the transparent conductive film laminated body after bonding with a thin glass substrate. Thereby, curl after heating by crystallization of a transparent conductive film, metal wiring work, etc. can be suppressed, it can process and convey stably and continuously, and can secure the subsequent process yield.

(Transparent resin film)

The transparent resin film is formed of amorphous resin and has characteristics of high transparency and low water absorption. Adoption of amorphous resin enables control of the optical characteristics of the transparent conductive film. Although it does not specifically limit as amorphous resin, It is preferable that it is excellent in transparency, mechanical strength, thermal stability, water barrier property, isotropy, etc., and acrylic type, such as polycarbonate, cycloolefin, polyvinyl chloride, polymethyl methacrylate, etc. Resin, Polystyrene, Polymethylmethacrylate Styrene Copolymer, Polyacrylonitrile, Polyacrylonitrile Styrene Copolymer, High Impact Polystyrene (HIPS), Acrylonitrile Butadiene Styrene Copolymer (ABS Resin), Polyarylate, Poly Sulfone, polyether sulfone, polyphenylene ether and the like. Cycloolefin resin, polycarbonate resin, etc. are preferable from a viewpoint of high transparency, low water absorption, heat resistance, etc.

It will not specifically limit, if it is resin which has a unit of the monomer which consists of cyclic olefin (cycloolefin) as cycloolefin resin. As cycloolefin resin used for a transparent resin film, any of a cycloolefin polymer (COP) or a cycloolefin copolymer (COC) may be sufficient. A cycloolefin copolymer means amorphous cyclic olefin resin which is a copolymer of cyclic olefin and olefins, such as ethylene.

As said cyclic olefin, a polycyclic cyclic olefin and a monocyclic cyclic olefin exist. As such a polycyclic olefin, norbornene, methyl norbornene, dimethyl norbornene, ethyl norbornene, ethylidene norbornene, butyl norbornene, dicyclopentadiene, dihydrodicyclopenta Dienes, methyldicyclopentadiene, dimethyldicyclopentadiene, tetracyclododecene, methyltetracyclododecene, dimethylcyclotetradodecene, tricyclopentadiene, tetracyclopentadiene and the like. In addition, examples of the monocyclic cyclic olefin include cyclobutene, cyclopentene, cyclooctene, cyclooctadiene, cyclooctatriene, and cyclododecatene.

Cycloolefin resin can also be obtained as a commercial item, For example, "ZEONOR" by Nippon-Xeon company, "ARTON" by JSR company, "TOPAS" by polyplastics company, "APEL" by Mitsui Chemicals company, etc. are mentioned, for example.

Although polycarbonate resin is not specifically limited, For example, aliphatic polycarbonate, aromatic polycarbonate, aliphatic-aromatic polycarbonate, etc. are mentioned. Specifically, for example, as a polycarbonate (PC) using bisphenols, bisphenol A polycarbonate, branched bisphenol A polycarbonate, expanded polycarbonate, copolycarbonate, block copolycarbonate, polyester carbonate, polyphosphonate carbonate And diethylene glycol bisallylcarbonate (CR-39). Polycarbonate resins include those blended with other components such as bisphenol A polycarbonate blends, polyester blends, ABS blends, polyolefin blends, styrene-maleic anhydride copolymer blends. As a commercial item of polycarbonate resin, "Keiwa" Opcon ", Teijin Co., Ltd." Fanlite ", Mitsubishi Gas Chemical Co., Ltd." Yufilon (ultraviolet absorber containing polycarbonate) "etc. are mentioned.

The cured resin layer, the transparent conductive film, etc. which are formed on a transparent resin film by giving a transparent resin film previously a sputtering, corona discharge, flame, ultraviolet irradiation, electron beam irradiation, chemical conversion, oxidation, etc., to a surface, and are formed on a transparent resin film, etc. You may improve the adhesiveness of the. Moreover, before forming a cured resin layer or a transparent conductive film, you may damp and clean a transparent resin film surface by solvent washing, ultrasonic washing, etc. as needed.

It is preferable that the thickness of a transparent resin film exists in the range of 20-75 micrometers, It is more preferable to exist in the range of 25-70 micrometers, It is still more preferable to exist in the range of 30-65 micrometers. When the thickness of a transparent resin film is less than the lower limit of the said range, mechanical strength may become inadequate and operation which continuously forms a transparent conductive film by making a film base material into a roll may become difficult. On the other hand, when thickness exceeds the upper limit of the said range, the improvement of the scratch resistance of a transparent conductive film and the spot property for a touch panel may not be aimed at. Moreover, when thickness is in the said range, since it becomes easy to be influenced at the time of a heating more, when the transparent conductive film of a transparent conductive film is made down, it can design so that it may curl largely in concave direction beforehand, bonding a thin glass, and a transparent conductive film When it is set as a laminated body, curl generation after a heating process can be suppressed.

Although glass transition temperature (Tg) of 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 more preferable. Thereby, since generation | occurrence | production of the curl after heating processes, such as drying, can be suppressed when it is set as a transparent conductive film laminated body, the process conveyance of a transparent conductive film laminated body becomes easy.

The thermal contraction rate of MD direction and TD direction at the time of heating for 90 minutes at 130 degreeC of the resin film original fabric (film before carrying out heat processing etc. before laminating a cured resin layer) which forms a transparent resin film is 0.3% or less. It is preferable, it is more preferable that it is 0.2% or less, and it is still more preferable that it is 0.1% or less. Thereby, it becomes a transparent resin film excellent in workability, transparency, dimensional stability at the time of heating, etc. Moreover, since generation | occurrence | production of the curl after heating processes, such as drying, can be suppressed when it is set as a transparent conductive film laminated body, the process conveyance of a transparent conductive film laminated body becomes easy.

It is easy to make the said transparent resin film into the film of the low phase difference whose phase difference R0 of in-plane direction is 0 nm-10 nm, and the (lambda) / 4 film whose phase difference of in-plane direction is about 80 nm-150 nm, and with a polarizing plate When used, visibility can be made favorable. In addition, in-plane phase difference (R0) says the phase difference value in retardation film (layer) surface measured with the light of wavelength 589nm in 23 degreeC.

(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. Since the transparent resin film formed from the amorphous resin is easily scratched in each process such as formation of a transparent conductive film, patterning of the transparent conductive film, or mounting on an electronic device, the first cured water may be formed on both surfaces of the transparent resin film as described above. The ground layer and the second cured resin layer are formed.

The cured resin layer is a layer obtained by curing the curable resin. It is preferable that a cured resin layer contains resin and particle | grains. As resin to be used, although the thing which has sufficient intensity | strength as a film after hardening resin layer formation, and transparency can be used without a restriction | limiting in particular, thermosetting resin, ultraviolet curable resin, electron beam curable resin, two-liquid mixed resin, etc. are mentioned. . Among these, the ultraviolet curable resin which can form a cured resin layer efficiently by the hardening process by ultraviolet irradiation by simple processing operation is preferable.

As ultraviolet curable resin, various things, such as polyester type, an acryl type, urethane type, an amide type, silicone type, an epoxy type, etc. are mentioned, A ultraviolet curable monomer, an oligomer, a polymer, etc. are contained. UV-curable resin used preferably is acrylic resin and epoxy resin, More preferably, it is acrylic resin.

The cured resin layer may contain particles. By mix | blending particle | grains in a cured resin layer, a ridge | bulb can be formed in the surface of a cured resin layer, and blocking resistance can be preferably given to a transparent conductive film.

As said particle | grain, what has transparency, such as various metal oxide, glass, a plastic, can be used without a restriction | limiting in particular. For example, various polymers such as inorganic particles such as silica, alumina, titania, zirconia, calcium oxide, polymethyl methacrylate, polystyrene, polyurethane, acrylic resin, acrylic-styrene copolymer, benzoguanamine, melamine and polycarbonate And crosslinked or uncrosslinked organic particles, silicon particles, and the like. Although the particle | grains can select suitably 1 type, or 2 or more types, and can use it, Organic type particle | grains are preferable. As organic particle | grains, acrylic resin is preferable from a refractive index viewpoint.

The modest particle diameter of the particle can be appropriately set in consideration of the degree of protrusion of the ridge of the cured resin layer, the relationship with the thickness of the flat region other than the ridge, and the like, and is not particularly limited. Moreover, it is preferable that it is 0.5-5 micrometers, and, as for the most frequent particle diameter of a particle | grain, from a viewpoint of fully providing blocking resistance to a transparent conductive film and fully suppressing a raise of a haze, it is more preferable that it is 1.0-2 micrometers. In addition, in this specification, "mode of particle diameter" means the particle diameter which shows the maximum value of particle distribution, and it uses the flow type particle image analyzer (The product made by Sysmex, product name "FPTA-3000S") under predetermined conditions (Sheath liquid). : Ethyl acetate, measuring mode: HPF measurement, measuring system: total count). As a measurement sample, the particle | grains were diluted by 1.0 weight% with ethyl acetate, and the thing disperse | distributed uniformly using the ultrasonic cleaner is used.

It is preferable that content of particle | grains is 0.05-1.0 weight part with respect to 100 weight part of resin solid content, It is more preferable that it is 0.1-0.5 weight part, It is further more preferable that it is 0.2-0.3 weight part. When content of the particle | grains in a cured resin layer is small, there exists a tendency for a ridge sufficient to provide blocking resistance or slipperiness to the surface of a cured resin layer to become difficult to form. On the other hand, when content of particle | grains is too big | large, haze of a transparent electroconductive film arises from the light scattering by particle | grains, and there exists a tendency for visibility to fall. Moreover, when content of particle | grains is too big | large, streaks generate | occur | produce at the time of formation of a cured resin layer (at the time of application | coating of a solution), visibility may be impaired, or the electrical characteristic of a transparent conductive film may become nonuniform.

The cured resin layer applies a resin composition containing each curable resin and particles to be added as necessary, a crosslinking agent, an initiator, a sensitizer and the like on a transparent resin film, and when the resin composition contains a solvent, drying of the solvent And hardening by application of heat, an active energy ray, or both. The heat may be a known means such as an air circulation oven or an IR heater, but is not limited to these methods. Examples of active energy rays include ultraviolet rays, electron beams, gamma rays and the like, but are not particularly limited.

A cured resin layer can be formed into a film by the wet coating method (coating method) etc. using the said material. For example, when forming indium oxide (ITO) containing tin oxide as a transparent conductive film, when the surface of the cured resin layer which is an underlayer is smooth, the crystallization time of a transparent conductive film can also be shortened. From this viewpoint, it is preferable that the cured resin layer is formed into a film by the wet coating method.

It is preferable that both the thickness of a 1st cured resin layer and the thickness of a 2nd cured resin layer are 2 micrometers or less, More preferably, they are 0.1 micrometer-1.5 micrometers, More preferably, they are 0.3 micrometer-1.2 micrometers. Moreover, it is preferable that the thickness of a 2nd cured resin layer is the same as or thinner than the thickness of a 1st cured resin layer. That is, it is preferable that it is 10 to 100% of the thickness of a 1st cured resin layer, It is more preferable that it is 20 to 90%, and, as for the thickness of a 2nd cured resin layer, it is still more preferable that it is 30 to 80%. Thereby, the flaw generation | occurrence | production of a transparent resin film can be prevented when conveyed by the roll-to-roll manufacturing method. Moreover, when the thickness of a cured resin layer exists in the said range, it can prevent that visibility, such as a touch panel, deteriorate, and it can design so that it may curl in a concave direction beforehand when the transparent conductive film of a transparent conductive film is made down. Therefore, curl generation after a heating process can be suppressed when a thin glass is bonded together and it is set as a transparent conductive film laminated body.

(Transparent conductive film)

Although a transparent conductive film can be formed on a transparent resin film, it is preferable to form on the 1st cured resin layer formed in the one surface side of a transparent resin film. The constituent material of the transparent conductive film is not particularly limited as long as it contains an inorganic material, and is selected from the group consisting of indium, tin, zinc, gallium, antimony, titanium, silicon, zirconium, magnesium, aluminum, gold, silver, copper, palladium, and tungsten. Metal oxides of at least one metal selected are preferably used. The said metal oxide may further contain the metal atom shown to the said group as needed. For example, indium oxide (ITO) containing tin oxide, tin oxide (ATO) containing antimony, etc. are used preferably.

Although the thickness of a transparent conductive film is not specifically limited, In order to make the surface resistance into the continuous film which has the favorable electroconductivity of 1 * 10 <^3> ohm / square or less, it is preferable to make thickness 10-35 nm. When the film thickness becomes too thick, it causes a decrease in transparency, etc., so it is more preferably 15 to 35 nm, still more preferably within the range of 20 to 30 nm. If the thickness of the transparent conductive film is less than 10 nm, the electrical resistance of the film surface is high, and it is difficult to form a continuous film. On the other hand, when the thickness of a transparent conductive film exceeds 35 nm, a fall of transparency may be caused. Moreover, by forming a transparent conductive film in the said thickness on a 1st cured resin layer, when making the transparent conductive film of a transparent conductive film down, it can design so that it may curl in large concave direction beforehand.

The formation method of a transparent conductive film is not specifically limited, A conventionally well-known method can be employ | adopted. Specifically, dry processes, such as a vacuum vapor deposition method, a sputtering method, an ion plating method, can be illustrated, for example. Moreover, the appropriate method can also be employ | adopted according to the film thickness required.

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

About the definition of "crystalline", the transparent conductive film in which the transparent conductive film was formed on the transparent resin film was immersed in 20 degreeC and 5 weight% hydrochloric acid for 15 minutes, and then washed with water and dried, and the resistance between terminals between 15 mm was made into When the measurement is carried out by a tester and the resistance between terminals does not exceed 10 kΩ, the conversion of the ITO film to the crystalline phase is completed. In addition, the measurement of a surface resistance value can be measured by the 4-probe method according to JISK7194.

In addition, the transparent conductive film may be patterned by etching or the like. About patterning of a transparent conductive film, it can implement using the technique of conventionally well-known photolithography. As etching liquid, an acid is used preferably. 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, mixtures thereof, and aqueous solutions thereof. For example, in the transparent conductive film used for a capacitive touch panel or a matrix type resistive touch panel, it is preferable that a transparent conductive film is patterned in stripe form. In addition, when patterning a transparent conductive film by etching, when crystallizing a transparent conductive film first, patterning by etching may become difficult. Therefore, it is preferable to perform annealing of a transparent conductive film after patterning a transparent conductive film.

(Optical adjustment layer)

One or more optical adjusting layers may be further included between the first cured resin layer and the transparent conductive film. The optical adjustment layer can reduce the transmittance difference and the reflectance difference between the pattern portion in which the pattern remains and the opening in which the pattern does not remain, when the transmittance rise of the transparent conductive film or the transparent conductive film is patterned. It is used to obtain a film.

It is preferable that an optical adjustment layer contains binder resin and microparticles | 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 containing acrylic resins are preferred. .

It is preferable that the refractive index of an optical adjustment layer is 1.6-1.8, It is more preferable that it is 1.62-1.78, It is still more preferable that it is 1.65-1.75. Thereby, a transmittance difference and a reflectance difference can be reduced, and the transparent conductive film excellent in visibility can be obtained.

The optical adjustment layer may have microparticles whose average particle diameter is 1 nm-500 nm. It is preferable that content of microparticles | fine-particles in an optical adjusting layer is 0.1 weight%-90 weight%. It is preferable that it is the range of 1 nm-500 nm, and, as above-mentioned, as for the average particle diameter of the microparticles | fine-particles used for an optical adjustment layer, it is more preferable that it is 5 nm-300 nm. Moreover, as for content of the microparticles | fine-particles in an optical adjustment layer, it is more preferable that they are 10 weight%-80 weight%, and it is still more preferable that they are 20 weight%-70 weight%. By containing microparticles | fine-particles in an optical adjusting layer, adjustment of the refractive index of an optical adjusting layer itself can be performed easily.

As an inorganic oxide which forms microparticles | fine-particles, microparticles | fine-particles, such as silicon oxide (silica), hollow nano silica, titanium oxide, aluminum oxide, zinc oxide, tin oxide, zirconium oxide, and niobium oxide, are mentioned, for example. 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 individually by 1 type and may use 2 or more types together.

The optical adjusting layer can 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), etc. (the numerical value in parentheses shows a refractive index).

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

It is preferable that the thickness of an optical adjustment layer is 40 nm-150 nm, It is more preferable that it is 50 nm-130 nm, It is further more preferable that it is 70 nm-120 nm. If the thickness of the optical adjustment layer is excessively small, it is difficult to form a continuous coating. Moreover, when the thickness of an optical adjustment layer is excessively large, there exists a tendency for transparency of a transparent conductive film to fall, or a crack becomes easy to occur.

(Metal wiring)

Although metal wiring can be formed by etching after forming a metal layer on a transparent conductive film, it is preferable to form using a photosensitive metal paste as follows. That is, in the metal wiring, after the transparent conductive film is patterned, a photosensitive conductive paste described later is applied onto the transparent resin film or the transparent conductive film, a photosensitive metal paste layer is formed, and a photomask is laminated or approached. After exposing to a photosensitive metal paste layer through a photomask, and then developing and pattern formation, it is obtained through a drying process. That is, the pattern formation of a metal wiring is possible by the well-known photolithography method.

It is preferable that the said photosensitive electrically conductive paste contains electroconductive particle, such as a metal powder, and the photosensitive organic component. As a material of the electroconductive particle of a metal powder, it is preferable to contain at least 1 sort (s) chosen from the group of Ag, Au, Pd, Ni, Cu, Al, and Pt, More preferably, it is Ag. It is preferable that the volume average particle diameter of the electroconductive particle of a metal powder is 0.1 micrometer-2.5 micrometers.

As electroconductive particle other than a metal powder, the metal coating resin particle which coat | covered the resin particle surface with the metal may be sufficient. Although the above-mentioned particle | grains are contained as a material of resin particle, acrylic resin is preferable. The metal-coated resin particles are obtained by reacting a silane coupling agent on the surface of the resin particles and coating the surface with a metal. By using a silane coupling agent, dispersion of a resin component can be stabilized and uniform metal coating resin particle can be formed.

The photosensitive electrically conductive paste may further contain the glass frit. It is preferable that volume average particle diameters are 0.1 micrometer-1.4 micrometers, and, as for glass frit, it is preferable that 90% particle diameters are 1-2 micrometers, and top size is 4.5 micrometers or less. The composition of the glass frit is preferably not particularly limited, Bi ₂ O ₃ which is blended in the range of 30% by weight to 70% by weight with respect to the total. An oxide which may include in addition to the Bi ₂ O _3, and may include _{SiO 2, B 2 O 3,} ZrO 2, Al 2 O 3. _{Na 2 O, K 2 O,} Li 2 O is substantially preferable that the alkali-free glass frit that does not contain a.

It is preferable that the photosensitive organic component contains a photosensitive polymer and / or a photosensitive monomer. As the photosensitive polymer, light is applied to the side chains or molecular ends of an acrylic resin comprising a polymer of a component selected from a compound having a carbon-carbon double bond such as methyl (meth) acrylate and ethyl (meth) acrylate or a copolymer thereof. Addition of a reactive group, etc. are used preferably. Preferred photoreactive groups include ethylenically unsaturated groups such as vinyl group, allyl group, acryl group, and methacryl group. It is preferable that content of the photosensitive polymer is 1-30 weight%, and 2-30 weight%.

As a photosensitive monomer, (meth) acrylate type monomers, such as methacrylacrylate and ethyl acrylate, (gamma) -methacryloxypropyl trimethoxysilane, 1-vinyl-2-pyrrolidone, etc. are mentioned, 1 type, or 2 or more types can be used.

In the photosensitive electrically conductive paste, it is preferable that the photosensitive organic component contains 5-40 weight% with respect to 100 weight part of metal powders, More preferably, it is 10 weight part-30 weight part. Moreover, it is preferable to use a photoinitiator, a sensitizer, a polymerization inhibitor, and an organic solvent for the photosensitive electrically conductive paste of this invention as needed.

The thickness of the metal layer is not particularly limited. For example, when a part of the in-plane 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 pattern wiring after formation has a desired resistance value. Therefore, it is preferable that it is 0.01-200 micrometers, and, as for the thickness of a metal layer, it is more preferable that it is 0.05-100 micrometers. When the thickness of the metal layer is within the above range, the resistance of the pattern wiring does not become too high, and power consumption of the device does not increase. Moreover, the production efficiency of film-forming of a metal layer increases, the amount of heat of integration at the time of film-forming becomes small, and it becomes difficult to produce heat wrinkle in a film.

In the case where 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 of a patterned transparent conductive film, and the metal wiring made from the photosensitive conductive paste is formed of a non-display portion ( For example, it is used for the wiring part of the peripheral part. The transparent conductive film may also be used in the non-display portion, in which case metal wiring may be formed on the transparent conductive film.

<Transparent conductive film laminated body>

A transparent conductive film laminated body is formed by laminating a glass substrate through an adhesive layer on the other surface side with the transparent conductive film of the said transparent conductive film. The transparent conductive film laminated body cuts the transparent conductive film laminated body into 210 mm x 260 mm, and the difference of the average curl value A of the four corner parts, and the curl value B of the center part after heating for 90 minutes at 130 degreeC, making a transparent conductive film an upper surface ( It is preferable that A-B) is 2.0 mm or less, It is more preferable that it is less than 2.0 mm, It is still more preferable that it is 1.8 mm or less. The lower limit is not particularly limited, but is preferably 0.5 mm or more. When the curling amount is suppressed in this way, when conveying the transparent conductive film layered product, suction is possible by air, and processing and conveyance can be continuously performed.

(Glass substrate)

A glass substrate laminate | stacks a transparent conductive film through an adhesive layer on the other surface side with the transparent conductive film of a transparent conductive film. Although it does not specifically limit as a material which forms a glass substrate, What is excellent in transparency, surface smoothness, thermal stability, water barrier property, isotropy, etc. is preferable, and soda lime glass, borosilicate glass, etc. are mentioned. These glasses may be chemically strengthened and the alkali elution prevention layer may be formed in the surface. Moreover, in order to raise the adhesive force with another layer, you may process the glass surface with a silane coupling agent.

It is preferable that it is 0.1-1.5 mm, and, as for the thickness of a glass substrate, it is more preferable that it is 0.3-1.0 mm. If the thickness is too thin, breakage easily occurs in the glass when the transparent conductive film laminate is heated. On the other hand, if the thickness is too thick, thinning of the display becomes difficult and the flexibility is reduced. When the glass substrate of the thickness of such a range is made into the transparent conductive film down, it is possible to suppress curl generation after a heating process by bonding a transparent conductive film designed so that it may curl in a concave direction beforehand, and manufacturing a transparent conductive film laminated body. .

(Adhesive layer)

As an adhesive layer, if it has transparency, the following adhesive can be used without a restriction | limiting in particular. 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 compounds, fluorine compounds, natural rubbers, and synthetic rubbers. What uses a polymer, such as rubber | gum, etc. as a base polymer can be selected suitably, and can be used. In particular, an acrylic pressure-sensitive adhesive is preferably used in that it is excellent in optical transparency, exhibits proper wettability, cohesiveness and adhesiveness, and also has excellent weather resistance and heat resistance.

The formation method of an adhesive layer is not restrict | limited, The method of apply | coating an adhesive composition to a peeling liner, and after drying, the method of transferring to a glass substrate (transcription method), the method of apply | coating and drying an adhesive composition directly to a glass substrate (straight method) Etc. can be mentioned. Moreover, a tackifier, a plasticizer, a filler, antioxidant, a ultraviolet absorber, a silane coupling agent, etc. can also be used suitably for an adhesive as needed.

Preferable thickness of an adhesive layer is 5 micrometers-100 micrometers, More preferably, they are 10 micrometers-50 micrometers, More preferably, they are 15 micrometers-35 micrometers.

<Touch panel>

The transparent conductive film laminate can be suitably applied, for example, as a transparent electrode of an electronic device such as a touch panel such as a capacitance method or a resistive film method. Moreover, since the transparent conductive film laminated body of this invention is laminated | stacked on a glass substrate, it is applicable suitably as a transparent electrode of electronic devices, such as a touch panel, as it is.

At the time of formation of a touchscreen, it can form using the above-mentioned transparent conductive film laminated body. In this invention, although the laminated body which a glass substrate bonded together was formed in the surface on the side in which the transparent conductive film of a transparent conductive film is not formed through a transparent adhesive layer, a glass substrate may consist of one board | substrate, and two pieces The laminated body of the above board | substrate (for example, what laminated | stacked through the transparent adhesive layer) may be sufficient. As an adhesive layer used for bonding a transparent conductive film and a board | substrate, as long as it has transparency as mentioned above, it can use without a restriction | limiting in particular.

When the said transparent conductive film laminated body is used for formation of a touch panel, since the generation amount and the direction of the curl after a heating process, such as drying, can be suppressed, conveyance of a transparent conductive film laminated body becomes easy, and at the time of touch panel formation Excellent handling properties. 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 use for the shield use which shields the electromagnetic wave and noise which generate | occur | produce from an electronic device.

<Manufacturing method of a transparent conductive film laminated body>

The manufacturing method of the transparent conductive film laminated body of this invention is a process of preparing the transparent conductive film in which the amorphous transparent conductive film was formed in the transparent resin film, and the transparent conductive film of a transparent conductive film through an adhesive layer on the other surface side. The process of laminating | stacking a glass substrate, 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. After making it a transparent conductive film laminated body, it is preferable to pass through this process of heat processing. Thereby, since a transparent conductive film is designed so that it may curl in a large concave direction beforehand when a transparent conductive film is made down, generation | occurrence | production of a curl can be suppressed in a transparent conductive film laminated body.

The transparent conductive film used for the process of preparing a transparent conductive film may form a cured resin layer on a transparent resin film, and may then form a transparent conductive film, and may form the transparent resin laminated body in which the cured resin layer was formed on the transparent resin film. It may obtain and then form a transparent conductive film on a cured resin layer, and may obtain a transparent conductive film in which the cured resin layer and the transparent conductive film were formed on the transparent resin film. Also about the optical adjustment layer mentioned above, you may obtain and use the transparent resin laminated body formed in advance.

The process of laminating | stacking a glass substrate forms an adhesive layer in a release base material, transfers an adhesive layer to a glass substrate, and interposes an adhesive layer on the side in which the transparent resin film of the 2nd cured resin layer of a transparent conductive film is not formed. The glass substrate may be laminated to form an adhesive layer directly on the glass substrate. Moreover, you may form an adhesive layer in the surface side opposite to the transparent conductive film of a transparent conductive film, and may laminate a glass substrate.

In order to crystallize the constituent components of the transparent conductive film, it is subjected to a heat treatment step. It is preferable to perform this heating temperature at the temperature of 130 degrees C or less, for example, More preferably, at 120 degrees C or less, processing time is 15 minutes-180 minutes, for example. Thereafter, the transparent conductive film is etched to form the pattern portion by the pattern. After the transparent conductive film is patterned, the above-mentioned photosensitive conductive paste is applied onto the transparent resin film or on the transparent conductive film, a photosensitive metal paste layer is formed, a photomask is laminated or proximate, the photo It is preferable to further include the process of exposing to a photosensitive metal paste layer through a mask, or obtaining a metal wiring by screen printing. It is preferable to perform the said drying process at 130 degrees C or less, and it is preferable that it is 120 degrees C or less. Since the transparent conductive film laminate has a heat treatment for crystallization, a subsequent etching step, and a metal wiring step, there are photomasks, positioning of the pattern of the transparent conductive film and the metal wiring, and the like. In that case, although the process of fixing to an adsorption plate is needed for alignment, since the quantity and direction of curl can be controlled even if it is dried in the said temperature range, it becomes possible not to go through the process of fixing to an adsorption plate.

Example

EMBODIMENT OF THE INVENTION 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 particle)

0.3 part by weight of an ultraviolet curable resin composition (trade name "UNIDIC (registered trademark) RS29-120" manufactured by DIC Corporation) and acrylic spherical particles (trade name "MX-180TA" manufactured by Soken Chemical Co., Ltd.) having a minimum particle diameter of 1.9 µm. The curable resin composition containing spherical particle containing was prepared.

(Formation of Cured Resin Layer)

The prepared spherical particle-containing curable resin composition was apply | coated to one surface of the polycycloolefin film (Nippon Xeon make brand name "ZEONOR (trademark)") whose thickness is 35 micrometers, and glass transition temperature is 165 degreeC, and formed the application layer. . Subsequently, an ultraviolet-ray was irradiated to the application layer from the side in which the application layer was formed, and the 2nd cured resin layer was formed so that thickness might be set to 1.0 micrometer. On the other side of a polycycloolefin film, the 1st cured resin layer was formed so that thickness might be set to 1.0 micrometer by the same method except having not added spherical particle to the above.

(Formation of Optical Control Layer)

A zirconia particle-containing ultraviolet curable composition (trade name "Opsta Z7412" manufactured by JSR) having a refractive index of 1.62 was applied to the first cured resin layer surface side of the polycycloolefin film having a cured resin layer formed on both surfaces thereof, and the application layer was applied. Formed. Subsequently, an ultraviolet-ray was irradiated to the application layer from the side in which the application layer was formed, and the optical adjustment layer was formed so that thickness might be set to 100 nm.

(Formation of the transparent conductive film)

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

(Formation of the transparent conductive film laminate)

By conventional solution polymerization, an acrylic polymer having a weight average molecular weight of 600,000 was obtained in butyl acrylate / acrylic acid = 100/6 (weight ratio). 6 weight part of epoxy type crosslinking agents (Mitsubishi Gas Chemical make brand name "Tetrad C (trademark)") was added with respect to 100 weight part of this acrylic polymer, and the acrylic adhesive was prepared. After applying the acrylic adhesive obtained by the above (thickness after drying: 20 micrometers) on the thin soda glass cut into 210 mm x 260 mm in thickness of 0.4 mm, a transparent conductive film is stuck so that a transparent conductive film may become on top. Combined, the transparent conductive film laminated body was produced.

Example 2

In Example 1, the hollow particle diameter of the spherical particle | grains contained in the 2nd cured resin layer which used the polycycloolefin film (Nippon Xeon make brand name "ZEONOR (trademark)") whose thickness is 50 micrometers as a transparent resin film is A transparent conductive film and a transparent conductive film laminate were produced in the same manner as in Example 1, except that 0.8 μm was used and the thickness of the second cured resin layer was 0.5 μm.

Example 3

In Example 1, after performing an annealing process at 150 degreeC for 3 minutes by the roll-to-roll manufacturing method after forming an optical adjustment layer, it carried out similarly to Example 1 except having formed a transparent conductive film, A transparent conductive film and a transparent conductive film The laminate was formed.

Example 4

In Example 1, except having used the polycycloolefin film (Nippon Xeon make brand name "ZEONOR (trademark)") whose thickness is 50 micrometers as a transparent resin film, A transparent conductive film and transparent electroconductivity by the method similar to Example 1 The film laminated body was produced.

Example 5

In Example 3, a transparent conductive film and transparent electroconductivity were performed by the same method as Example 3 except having used the polycycloolefin film (Nippon Xeon make brand name "ZEONOR (trademark)") whose thickness is 50 micrometers as a transparent resin film. The film laminated body was produced.

Comparative Example 1

In Example 1, the polycycloolefin film (The Nippon Xeon make brand name "ZEONOR (trademark)") whose thickness is 50 micrometers was used as a transparent resin film, and the thickness of the 2nd cured resin layer was 3.0 micrometers. A transparent conductive film and a transparent conductive film laminate were produced in the same manner as in Example 1.

Comparative Example 2

In Example 1, a transparent conductive film and transparent electroconductivity were performed by the same method as Example 1 except having used the polycycloolefin film (Nippon Xeon make brand name "ZEONOR (trademark)") of thickness 75micrometer as a transparent resin film. The film laminated body was produced.

Comparative Example 3

Example 1 WHEREIN: Except having used polyester resin (PET) (Mitsubishi resin make brand name "diafoil (trademark)") whose thickness is 50 micrometers and glass transition temperature is 70 degreeC as a transparent resin film. A transparent conductive film and a transparent conductive film laminate were produced in the same manner as the above.

<Evaluation>

(1) measurement of thickness

The thickness measured about the thing which has thickness of 1 micrometer or more with the micro gauge type thickness meter (made by Mitsutoyo Corporation). In addition, the thickness of less than 1 micrometer and the thickness (100 nm) of the optical adjustment layer were measured by the instantaneous multi-metering system (MCPD2000 by Otsuka Electronics Corporation). Like the thickness of an ITO film | membrane, the nano size thickness produced the sample for cross-sectional observation with FB-2000A (made by Hitachi High-Technologies Corporation), and the cross-sectional TEM observation used HF-2000 (made by Hitachi High-Technologies Corporation). The film thickness was measured. The evaluation results are shown in Table 1.

(2) Measurement of curl value in transparent conductive film

The transparent conductive film obtained by the Example and the comparative example was cut into 50 cm x 50 cm size. After heating at 130 degreeC for 90 minutes in the state which has an ITO surface, it was left to cool at room temperature (23 degreeC) for 1 hour. Thereafter, the samples were placed on the horizontal plane with the ITO plane down, the heights from the horizontal plane of the four corner portions were respectively 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. The value (A-B) which subtracted the curl value B from curl value A was computed as curl amount. The evaluation results are shown in Table 1.

(3) Measurement of curl value in transparent conductive film laminated body

The transparent conductive film laminate obtained by the Example and the comparative example was cut into 210 mm x 260 mm x 0.4 mm size. After heating at 130 degreeC for 90 minutes in the state which makes an ITO surface up, it was left to cool at room temperature (23 degreeC) for 1 hour. Then, the sample was placed on the horizontal surface with the ITO surface upward, the height from the horizontal surface of the four corner parts was respectively measured, and the average value (curl value A) was computed. Moreover, the height (curl value B) from the horizontal surface of the center part was measured. The value (A-B) which subtracted the curl value B from curl value A was computed as curl amount. The evaluation results are shown in Table 1.

(4) Thermal contraction rate in MD direction and TD direction

The thermal contraction rate of the longitudinal direction (MD direction) and the width direction (TD direction) of a transparent conductive film was computed as follows. Specifically, the transparent conductive film is cut out to a width of 100 mm and a length of 100 mm (test piece), and the four corners are cut in a cross, and the length before heating in the MD direction and the TD direction of the four center portions of the cross scratches (mm ) Was measured by a CNC three-dimensional measuring instrument (LEGEX774 manufactured by Mitsutoyo Corporation). Then, it put in oven and heat-processed (130 degreeC, 90 minutes). After cooling for 1 hour at room temperature, the length (mm) after heating in the MD direction and the TD direction of the four corners is measured again by a CNC three-dimensional measuring instrument, and the measured value is substituted into the following equation to determine the MD and TD directions. Each thermal contraction rate was calculated | required. 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 the specification of JISK7121.

(Results and Discussion)

In the transparent conductive films of Examples 1-5, the direction of curl generation is a concave direction when the transparent conductive film is down, and since curl generate | occur | produced largely with 7-28 mm in curl generation amount, in the transparent conductive film laminated body, The direction of generation was a concave direction when the transparent conductive film was placed upward, and curl generation could be suppressed to 1.1 to 2.0 mm. Moreover, in the transparent conductive films of Comparative Examples 1-2, since the direction of curl generation is a concave direction when the transparent conductive film is made down, since the amount of curl generation was small at 2-4 mm, in the transparent conductive film laminated body, it is transparent conductive When the membrane was placed up, the curl was formed in a concave direction and curled large at 2.5 to 4.3 mm. As mentioned above, it turns out that the curl amount of a transparent conductive film and the curvature after a transparent conductive film laminated body show a correlation, and when the curl amount of 5 mm or more generate | occur | produces in a transparent conductive film, the curl amount in a transparent conductive film laminated body can be reduced. there was. In addition, although the comparative example 3 is a value without a problem as a curl value, since PET film is used for a base material and there exists a high phase difference, it cannot be used as a base material of a polarizing plate.

1: transparent resin film
2: first cured resin layer
3: transparent conductive film
4: second cured resin layer
5: optical adjusting layer
6: glass substrate
7: adhesive layer
10: transparent conductive film

Claims (10)

As a transparent conductive film in which the 1st cured resin layer and the transparent conductive film are formed in this order in one surface side of a transparent resin film, and the 2nd cured resin layer was formed in the other surface side of the said transparent resin film,
The transparent resin film is made of an amorphous resin,
The thickness of the said 1st cured resin layer and the thickness of the said 2nd cured resin layer are all 1.5 micrometers or less,
The thermal contraction rate of MD direction and TD direction at the time of heating the said transparent conductive film at 130 degreeC for 90 minutes is 0.01 to 0.2%,
The difference (A-B) between the average curl value A of the four corner parts and the curl value B of the center part is 5 mm after the transparent conductive film is cut to a size of 50 cm × 50 cm and heated at 130 ° C. for 90 minutes with a transparent conductive film as the lower surface. The transparent conductive film which is the above. The method of claim 1,
The thickness of a said 2nd cured resin layer is a transparent conductive film which is equal to or thinner than the thickness of the said 1st cured resin layer. The method of claim 1,
The transparent conductive film provided with one or more optical adjustment layers between the said 1st cured resin layer and the said transparent conductive film further. The method of claim 1,
The said 2nd cured resin layer is a transparent conductive film containing resin and particle | grains. The method of claim 1,
In the said transparent resin film, amorphous resin is cycloolefin resin, thickness is 20-75 micrometers, glass transition temperature is 130 degreeC or more, and in the said transparent conductive film, the heat after heating at 130 degreeC for 90 minutes. The transparent conductive film whose shrinkage is less than 0.2% in MD and TD directions. The method of claim 3, wherein
The said optical adjustment layer contains binder resin and microparticles | fine-particles, the refractive index is 1.6-1.8, and is a transparent conductive film whose thickness is 40-150 nm. The method according to any one of claims 1 to 6,
The transparent conductive film is made of 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 Claim 1. The difference between the average curl value A of the four corner parts and the curl value B of the center part after cutting the transparent conductive film laminated body of Claim 8 to 210 mm x 260 mm size, and heating at 130 degreeC for 90 minutes using a transparent conductive film as an upper surface (A -B) is 2.0 mm or less, transparent conductive film laminated body. The touch panel obtained using the transparent conductive film laminated body of Claim 8 or 9.

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