JP2006156250A - Transparent conductor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent conductive material and a transparent conductive film an electrical resistance of which can be sufficiently prevented from rising or varying with time even in a highly humid environment or a chemical substance environment of an organic solvent, an organic gas, or the like. <P>SOLUTION: A transparent conductor comprises: a substrate 13; a conductive layer 14 containing conductive particles 11 and a resin 12; and a barrier layer 15 containing a metal or an inorganic compound; where the barrier layer 15 is placed at least in one position of positions between the substrate 13 and the conductive layer 14 and on a side of the substrate 13 opposite to the conductor layer 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transparent conductor.

  Transparent electrodes are used in LCDs, PDPs, organic ELs, touch panels, etc., and transparent conductors are used as such transparent electrodes. The transparent conductor is formed from a base and a conductive layer. These transparent conductors are formed by forming a sputtered film (conductive layer) on the base or by forming a conductive layer composed of conductive particles and a binder. There is. However, when these transparent conductors are used in a high-humidity environment or in a chemical substance atmosphere, the moisture and chemical substances are gradually absorbed to increase the electrical resistance value of the transparent conductor itself, and the electrical resistance value over time. There is a tendency for the change to be large.

  For this reason, when such a transparent conductor is used for a touch panel or the like and placed in the above environment, the operation of the touch panel may be gradually unstable.

Therefore, there is a demand for a transparent conductor that suppresses an increase in electrical resistance value and changes over time due to absorption of moisture and chemical substances. For example, as a resin for fixing conductive particles, a light-transmitting conductive material using a phenoxy resin or a mixed resin of phenoxy resin and an epoxy resin, or polyvinylidene fluoride, which is considered to have low hygroscopicity, has been proposed (for example, (See Patent Documents 1 and 2).
Japanese Patent Laid-Open No. 08-78164 JP 11-273874 A

  However, in recent years, there has been a demand for transparent conductors that require further high reliability of transparent conductors and that have a smaller change in electrical resistance value even under the above environment.

  The present invention has been made in view of the above circumstances, and a transparent conductor that can sufficiently suppress an increase in electrical resistance value and a change over time in a transparent conductor even in a high humidity environment or a chemical substance atmosphere. The purpose is to provide.

  As a result of diligent studies to solve the above problems, the present inventors have used the resin for a long period of time, particularly in a high humidity environment, even when the resin described in Patent Documents 1 and 2 is considered to have low moisture absorption. As a result, it was found that the resistance value may increase. That is, when the present invention diffuses a chemical substance such as moisture, solvent, or organic gas into a transparent conductor having a base and a conductive layer, the base swells, and the conductive layer is stretched along with this. It was considered that the junction point between the conductive particles was cut by this, and the resistance value increased. As a result of further earnest studies based on the above assumptions, the present inventors have found that the above problems can be solved by the following invention, and have completed the present invention.

  That is, the transparent conductor of the present invention comprises a base, a conductive layer containing conductive particles and a resin, and a barrier layer containing a metal or an inorganic compound, and the barrier layer is between the base and the conductive layer. And it is provided in at least any one of the opposite side to a conductive layer with respect to a base | substrate. Here, the transparent conductor in the present invention includes films and plates, and the film-like transparent conductor has a thickness in the range of 50 nm to 1 mm, and the plate-like transparent conductor has a thickness exceeding 1 mm. Say things.

  In the transparent conductor of the present invention, the barrier layer containing a metal or an inorganic compound can suppress the intrusion of chemical substances such as moisture, solvent, and organic gas that cause the substrate to swell. The swelling of the substrate is sufficiently prevented. Therefore, stretching of the conductive layer accompanying swelling of the substrate is prevented, and disconnection of the junction between the conductive particles is sufficiently prevented. Therefore, according to the transparent conductor of the present invention, an increase in electrical resistance value and a change with time in the transparent conductor can be sufficiently suppressed even under the environment.

  In the transparent conductor, the barrier layer is provided between the base and the conductive layer, the barrier layer is a conductive continuous layer containing a single metal or a conductive oxide, and the conductive layer It is preferable that the conductive particles and the barrier layer are in contact with each other.

  As described above, when the barrier layer is made of a metal or an inorganic compound, the transparent conductor can further prevent moisture, an organic gas, and the like from entering the substrate as described above. Further, in the transparent conductor, since the barrier layer is a conductive continuous layer, even when the transparent conductor is disconnected at the junction between the conductive particles due to the expansion of the substrate, the conductive continuous It becomes possible to ensure conduction between the conductive particles through the barrier layer which is a layer. Therefore, even in a high humidity environment or a chemical substance atmosphere, it is possible to further suppress an increase in electrical resistance value and a change with time in the transparent conductor.

In the transparent conductor, it is preferable that the barrier layer contains at least one inorganic compound selected from the group consisting of SiO ₂ , Al ₂ O ₃ , TiO ₂ , ZnO, or ZrO ₂ .

  When the barrier layer contains the inorganic compound, the transparent conductor obtained can increase the thickness of the barrier layer while maintaining transparency. Therefore, even under the above environment, an increase in electrical resistance value and a change with time can be more sufficiently suppressed.

  In the transparent conductor, the barrier layer is preferably provided between the base and the conductive layer and on the opposite side of the base from the conductive layer.

  By providing barrier layers on both sides of the substrate, it is possible to further suppress the intrusion of moisture, organic gas, or the like into the substrate. In addition, since the barrier layer itself has an effect of suppressing expansion and contraction, it is also effective in maintaining the shape of the substrate.

  According to the present invention, it is possible to provide a transparent conductor that can sufficiently suppress an increase in electrical resistance value and a change with time in the transparent conductor even in the above environment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

[First Embodiment]
First, a first embodiment of the transparent conductor 10 of the present invention will be described.

  FIG. 1 is a schematic cross-sectional view showing a first embodiment of the transparent conductor of the present invention. As shown in FIG. 1, the transparent conductor 10 of the present embodiment includes a base body 13, a conductive layer 14, and a barrier layer 15 provided between the base body 13 and the conductive layer 14.

  The base 13 contains a resin, and the conductive layer 14 includes a resin 12 and conductive particles 11 contained in the resin 12.

  The barrier layer 15 has a moisture permeability smaller than that of the substrate 13. For this reason, the barrier layer 15 can prevent moisture and organic gas that cause the base 13 from swelling into the base 13, and the base 13 can be sufficiently prevented from swelling. Accordingly, stretching of the conductive layer 14 accompanying swelling of the substrate 13 is prevented, and disconnection of the junction between the conductive particles 11 is sufficiently prevented. Therefore, according to the transparent conductor 10, an increase in electrical resistance value and a change with time in the transparent conductor 10 can be sufficiently suppressed even in a high humidity environment or a chemical substance atmosphere.

  Next, each layer of the conductive layer 14, the barrier layer 15, and the substrate 13 will be described in more detail.

<Conductive layer>
The conductive layer 14 contains the conductive particles 11 and the resin 12 as described above. The conductive particles 11 are filled so that adjacent conductive particles 11 are in contact with each other. As a result, the function as a conductor is exhibited.

  The conductive particles 11 are made of a transparent conductive oxide material. The transparent conductive oxide material is not particularly limited as long as it has transparency and conductivity. Examples of the transparent conductive oxide material include indium oxide or indium oxide, tin, zinc, tellurium, silver, One doped with at least one element selected from the group consisting of gallium, zirconium, hafnium or magnesium, tin oxide, or tin oxide with at least one selected from the group consisting of antimony, zinc or fluorine Examples include those doped with elements, zinc oxide, or zinc oxide doped with at least one element selected from the group consisting of aluminum, gallium, indium, boron, fluorine, and manganese.

  When the conductive particles 11 are made of the above material, the transparent conductor containing the conductive particles and the resin can further prevent the resistance value from changing with time even in a high humidity environment or a chemical substance atmosphere.

  The average particle diameter of the conductive particles 11 is preferably 10 nm to 80 nm. When the average particle size is less than 10 nm, the conductivity of the transparent conductor 10 tends to fluctuate more easily than when the average particle size is 10 nm or more. That is, the transparent conductor 10 according to the present embodiment exhibits conductivity due to oxygen defects generated in the conductive particles 11, but when the particle size of the conductive particles 11 is less than 10 nm, for example, when the external oxygen concentration is high. There is a possibility that oxygen deficiency is reduced and conductivity is changed. On the other hand, when the average particle diameter exceeds 80 nm, for example, in the wavelength region of visible light, light scattering increases compared to the case where the average particle size is 80 nm or less, and the transmittance of the transparent conductor 10 in the wavelength region of visible light. Decreases and the haze value tends to increase.

  Furthermore, the filling rate of the conductive particles 11 in the transparent conductor 10 is preferably 10% by volume to 70% by volume. When the filling rate is less than 10% by volume, the resistance value of the transparent conductor 10 tends to increase, and when the filling degree exceeds 70% by volume, the mechanical strength of the film tends to decrease.

  Thus, when the average particle diameter and the filling rate of the conductive particles 11 are within the above ranges, the transparency of the transparent conductor 10 can be further improved and the initial electrical resistance value can be reduced.

Also it preferably has a specific surface area of the conductive particles 11 is ^{10m 2} / ^g~50m 2 / g. When the specific surface area is less than 10 m ² / g, visible light scattering tends to increase, and when the specific surface area exceeds 50 m ² / g, the stability of the transparent conductive material tends to decrease. In addition, the specific surface area said here shall say the value measured after vacuum-drying a sample for 30 minutes at 300 degreeC using the specific surface area measuring apparatus (model | form: NOVA2000, the product made from Cantachrome).

  The conductive particles 11 are preferably treated with a surface treating agent on the surface of the conductive particles 11. By treating the surface of the conductive particles with the surface treatment agent, the conductive particles of the conductive layer can be prevented from adsorbing moisture.

  Examples of such surface treatment agents include silane coupling agents, silazane compounds, titanate coupling agents, aluminate coupling agents, phosphonate coupling agents, and the like. Among these, a silane coupling agent or a silazane compound is preferable. These surface treatment agents have various molecular structures and can be used as appropriate. In addition, these may be used individually by 1 type and may be used in mixture of 2 or more types.

  As the surface treatment agent, those having a terminal group that is a hydrophobic group are preferred. In this case, in the transparent conductor 10, the dispersibility of the conductive particles 11 in the resin 12 is improved, and as a result, the strength and transparency of the transparent conductor 10 are improved. Examples of such a surface treatment agent include hexamethyldisilazane.

  Examples of the hydrophobic group include a vinyl group, an alkyl group, an acryloyl group, a methacryloyl group, and an aryl group, and among these, a vinyl group, an alkyl group, an acryloyl group, a methacryloyl group, and an aryl group are preferable as the hydrophobic group. In this case, compared with the case where the hydrophobic group is a group other than the vinyl group or the like, when the transparent conductor 10 is placed in a high humidity environment, an increase in electrical resistance value and a change with time are further suppressed. .

  Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tertiary butyl group, and a stearyl group. Examples of the aryl group include a phenyl group and a naphthyl group.

  Since such a hydrophobic group does not participate in the chemical reaction between the surface treatment agent and the hydroxyl group contained in the conductive particles 11, the conductive particles treated with the obtained surface treatment agent have the hydrophobic group as a terminal group. In other words, it becomes possible to hydrophobize the surface of the conductive particles.

  The hydrophobic group is particularly preferably a vinyl group or a methyl group. In other words, the surface treatment agent is most preferably a surface treatment agent comprising a silane coupling agent or a silazane compound and having a terminal group that is a vinyl group or a methyl group as a hydrophobic group.

  When the hydrophobic group is a vinyl group, the surface treatment agent can be chemically bonded not only to the conductive particles but also to the resin 12. Therefore, in such a transparent conductor 10, the adhesion between the conductive particles 11 and the resin 12 can be further increased, and further, the diffusion of moisture into the resin 12 can be further suppressed. Therefore, it is possible to further suppress an increase in electrical resistance value and a change with time in a high humidity environment or in a chemical substance atmosphere.

  Further, since the surface treatment agent has a vinyl group at the end thereof, the conductive particles 11 treated with the surface treatment agent can be uniformly dispersed in the resin 12 in the conductive layer 14. Compared with the case where it is doing, a haze value will fall. Therefore, the transparent conductor 10 using the surface treating agent having a vinyl group at the terminal is particularly useful in terms of transparency. Further, in this case, since the contact area between the resin 12 and the conductive particles 11 is increased by uniformly dispersing the conductive particles 11 treated with the surface treatment agent in the resin 12, the strength of the transparent conductor 10 as a whole is increased. Will also improve.

  Further, the surface treatment agent may contain an epoxy group in addition to a vinyl group in the molecule. In this case, it is possible to make the resin 12 stronger by reacting the vinyl group by photoreaction and then reacting the epoxy group with heat later.

  On the other hand, when the hydrophobic group is a methyl group, the obtained transparent conductor 10 improves the dispersibility of the conductive particles 11 treated with the surface treatment agent in the transparent conductor 10, so that a pinning effect by a so-called filler is achieved. The moisture permeability of the transparent conductor 10 can be reduced. In addition, since the methyl group itself has a small molecular structure, the effect of steric hindrance at the junction between conductive particles treated with a surface treatment agent is minimal, and the junction is easy to ensure compared to other hydrophobic groups. Therefore, the transparent conductor 10 can further reduce the initial electrical resistance value.

  The amount of the surface treatment agent is preferably 0.1 parts by mass to 5 parts by mass with respect to 100 parts by mass of the conductive particles. When the blending amount is less than 0.1 parts by mass, the surface of the conductive particles 11 tends not to be sufficiently treated. When the blending amount exceeds 5 parts by mass, the effect of treating the surface of the conductive particles 11 is obtained. There is a tendency not to improve sufficiently.

  The resin 12 included in the conductive layer 14 is not particularly limited as long as it is a resin. As resin 12, what hardened a photocurable compound, a thermosetting compound, etc., ie, what has a crosslinked structure, is preferable. In this case, the moisture resistance of the transparent conductor is improved, and a change in resistance can be more sufficiently prevented. The photocurable compound may be any organic compound that is cured by light, and the thermosetting compound may be any organic compound that is cured by heat. Here, the organic compound includes a material that is a raw material of the resin 12, and specifically includes a monomer, a dimer, a trimer, an oligomer, and the like that can form the resin 12. Among the resins 12, a photocurable compound is preferable. When the curable compound is a photocurable compound, the curing reaction can be controlled, and the curing can be performed in a short time.

  As said photocurable compound, the monomer etc. which contain a vinyl group, an epoxy group, or those derivatives can be used preferably. These may be used alone or in a mixture of two or more. In addition, when the photocurable compound or the thermosetting compound is a polymer compound, the resin 12 may be a photocurable compound or a thermosetting compound.

  In the transparent conductor 10 of this embodiment, when the conductive particles 11 treated with the surface treatment agent described above have vinyl groups or the like on the surface, it is preferable to use an acrylic resin as the resin 12. In this case, the vinyl group of the conductive particles 11 treated with the surface treatment agent and the acrylic resin can be chemically bonded. As a result, the adhesion between the conductive particles 11 treated with the surface treatment agent and the cured acrylic resin can be further enhanced, and swelling of the acrylic resin can be suppressed. Therefore, it is possible to further suppress an increase in electrical resistance value and a change with time in a high humidity environment or a chemical substance atmosphere.

  The conductive layer 14 may further contain an additive as necessary. Examples of the additive include a flame retardant, an ultraviolet absorber, a colorant, and a plasticizer.

<Barrier layer>
The barrier layer 15 in the present embodiment is provided between the base 13 and the conductive layer 14, and exhibits an action of suppressing the intrusion of chemical substances such as moisture, a solvent, and an organic gas into the base 13.

  Examples of the material constituting the barrier layer 15 include metals, inorganic compounds, and inorganic-organic composites. Among these, materials containing metals or inorganic compounds are preferable. When the barrier layer 15 contains a metal or an inorganic compound, the transparent conductor 10 can further suppress the entry of chemical substances such as moisture, a solvent, and an organic gas into the substrate 13.

The metal used for the barrier layer 15 is not particularly limited, and examples thereof include Al, Ag, Au, Cr, Cu, Pd, Pt, Rh, and Zn. Examples of inorganic compounds include metal oxides such as SiO ₂ , Al ₂ O ₃ , TiO ₂ , ZnO, and ZrO ₂ , and conductive oxides such as ITO, IZO, ATO, FTO, AZO, and GZO. . Among these, the material constituting the barrier layer 15 is preferably a material containing a single metal or a conductive oxide. If the barrier layer 15 is a single metal or a conductive oxide, the barrier layer 15 itself has conductivity, so that the conductive particles contained in the conductive layer 14 and the barrier layer 15 are in contact with each other to improve conductivity. Is possible.

  Here, when the conductive particles contained in the conductive layer 14 and the barrier layer 15 are in contact with each other or are conductive, the barrier layer 15 is preferably a conductive continuous layer. As described above, when the barrier layer 15 is a conductive continuous layer, even when the transparent conductor 10 is cut off at the junction between the conductive particles 11 due to the expansion of the base 13, the conductive continuous layer It becomes possible to ensure conduction between the conductive particles 11 through a certain barrier layer 15. Accordingly, it is possible to further suppress an increase in electrical resistance value and a change with time in the transparent conductor 10 even in a high humidity environment or a chemical substance atmosphere.

Furthermore, the barrier layer 15 preferably contains at least one conductive oxide selected from the group consisting of SiO ₂ , Al ₂ O ₃ , TiO ₂ , ZnO, or ZrO ₂ . When the barrier layer 15 contains these compounds, the obtained transparent conductor 10 can increase the thickness of the barrier layer 15 while maintaining transparency. For this reason, it is possible to further suppress an increase in electrical resistance value and a change with time in the transparent conductor 10 even in a high humidity environment or in a chemical substance atmosphere.

<Substrate>
The base 13 is not particularly limited as long as it is made of a material transparent to high energy rays and visible light described later. That is, the substrate 13 may be a known transparent film or plate, for example, a polyester film such as polyethylene terephthalate (PET), a polyolefin film such as polyethylene or polypropylene, a polycarbonate film, an acrylic film, norbornene film (manufactured by JSR Corporation, Arton). Etc.). In addition to the resin, the base 13 may contain a filler component such as silica.

<Manufacturing method>
Next, a method for manufacturing the transparent conductor 10 according to the present embodiment will be described in the case where the conductive particles described above are those in which indium oxide is doped with tin (hereinafter referred to as “ITO”).

  The barrier layer 15 is obtained by a sputtering method, a vapor deposition method, or a coating method. As the barrier layer 15, one having a gas permeability smaller than that of the substrate 13 is preferably used. Here, before the barrier layer 15 is formed, a pretreatment such as an anchor layer or a corona treatment may be provided on the substrate 13 in advance. When an anchor layer is provided on the base 13 in advance or a corona treatment is performed, the barrier layer 15 can be more firmly fixed on the base 13. As the anchor layer, polyurethane, silicone or the like is preferably used.

  The barrier layer 15 is obtained by forming a continuous layer of metal and inorganic oxide on the substrate 13. In this embodiment, the barrier layer 15 is formed by sputtering an inorganic oxide on the substrate 13. When the sputtering method is used, there is an advantage that it is dense and the film thickness can be easily controlled.

  Next, a conductive layer 14 containing the conductive particles 11 and the resin 12 is formed on the barrier layer 15. Here, the conductive particles 11 will be described.

  First, indium chloride and tin chloride are coprecipitated by neutralization using an alkali (precipitation step). At this time, the by-product salt is removed by decantation or centrifugation. The obtained coprecipitate is dried, and the obtained dried product is subjected to atmosphere firing and pulverization. In this way, the conductive particles 11 are manufactured. The firing treatment is preferably performed in a nitrogen atmosphere or a rare gas atmosphere such as helium, argon, or xenon from the viewpoint of controlling oxygen defects.

  Here, the conductive particles 11 preferably have a surface treated with a surface treating agent as described above. In this case, it can be obtained by mixing and reacting the conductive particles 11 and the surface treatment agent.

  The conductive particles 11 thus obtained and a photocurable compound as a compound that forms the resin 12 are mixed and dispersed in a liquid to obtain a dispersion. Examples of the liquid in which the conductive particles 11 and the photocurable compound are dispersed include saturated hydrocarbons such as hexane, aromatic hydrocarbons such as toluene and xylene, alcohols such as methanol, ethanol, propanol, and butanol, acetone, methyl ethyl ketone, Ketones such as isobutyl methyl ketone and diisobutyl ketone, esters such as ethyl acetate and butyl acetate, ethers such as tetrahydrofuran, dioxane and diethyl ether, N, N-dimethylacetamide, N, N-dimethylformamide, N-methylpyrrolidone And amides. At this time, the photocurable compound may be used by dissolving in the liquid.

  The dispersion thus obtained is applied onto the resin layer 15. In addition, when using the said liquid, it is preferable to give a drying process after application | coating. Examples of the coating method include a reverse roll method, a direct roll method, a blade method, a knife method, an extrusion method, a nozzle method, a curtain method, a gravure roll method, a bar coating method, a dip method, a kiss coating method, and a spin coating method. It can be applied by a squeeze method or a spray method. And after apply | coating the said electrically-conductive particle 11 and a photocurable compound, a high energy ray is irradiated and a photocurable compound is hardened. Thereby, the conductive layer 14 is formed. In addition, the high energy ray mentioned above may be an electron beam, a gamma ray, an x ray other than an ultraviolet-ray, for example.

  And the transparent conductor 10 shown in FIG. 1 is obtained.

  The transparent conductor 10 thus obtained can be suitably used as a noise countermeasure component, a heating element, an EL electrode, a backlight electrode, an LCD, a PDP, a touch panel, or the like.

[Second Embodiment]
Next, a second embodiment of the transparent conductor of the present invention will be described.

  FIG. 2 is a schematic cross-sectional view showing a second embodiment of the transparent conductor 20 of the present invention. As shown in FIG. 2, the transparent conductor 20 of this embodiment is different from the transparent conductor 10 of the first embodiment in that a barrier layer 16 is further provided on the opposite side of the base layer 13 from the conductive layer 14. Is different. The barrier layer 16 has the same function as the barrier layer 15. That is, the barrier layer 16 has a gas permeability smaller than that of the substrate 13, as with the barrier layer 15, and is made of the same material as the barrier layer 15. The barrier layer 15 and the barrier layer 16 may be made of the same material or different materials.

  Thus, by providing the barrier layer 15 and the barrier layer 16 on both sides of the base 13, the transparent conductor 20 of the present embodiment can further suppress the penetration of moisture and organic gas into the base, Swelling of the substrate 13 is sufficiently prevented. Further, the barrier layer 16 itself has a function of suppressing expansion and contraction. Accordingly, stretching of the conductive layer 14 accompanying swelling of the substrate 13 is prevented, and disconnection of the junction between the conductive particles 11 is sufficiently prevented. Therefore, according to the transparent conductor 20, an increase in electrical resistance value and a change with time in the transparent conductor 20 can be sufficiently suppressed even in a high humidity environment or a chemical substance atmosphere.

<Manufacturing method>
A method for manufacturing the transparent conductor 20 will be described.

  In the transparent conductor 20 of the present embodiment, the barrier layer 15 and the barrier layer 16 are formed on both surfaces on the base 13. Here, before forming the barrier layer 15 and the barrier layer 16, it is preferable to provide an anchor layer in advance or perform corona treatment on the base 13. If an anchor layer is provided on the base 13 in advance or a corona treatment is performed, the barrier layer 15 and the barrier layer 16 can be more firmly fixed on the base 13. In addition, as said anchor layer, a polyurethane, silicone, etc. are used suitably, for example.

  The barrier layer 15 and the barrier layer 16 are obtained by forming a continuous layer of metal and inorganic oxide. In the present embodiment, the barrier layer 15 and the barrier layer 16 are formed by sputtering an inorganic oxide on the substrate 13. When the sputtering method is used, there is an advantage that it is dense and the film thickness can be easily controlled.

  Next, a conductive layer 14 containing the conductive particles 11 and the resin 12 is formed on the barrier layer 15. The conductive layer 14 is formed in the same manner as the transparent conductor 10, and the transparent conductor 20 shown in FIG. 2 is obtained.

  The transparent conductor 20 thus obtained can be suitably used as a noise countermeasure component, a heating element, an EL electrode, a backlight electrode, an LCD, a PDP, a touch panel, or the like.

  The present invention is not limited to the first and second embodiments. For example, in the first embodiment, the resin is a photocurable compound, and the photocurable compound is applied on the barrier layer 15 or the substrate 13 and cured by irradiation with light. The transparent conductor 10 may be formed by dissolving a resin obtained by curing by irradiating light in a solvent, applying the resin on one surface of the substrate 13, and drying the resin.

  In the production of the transparent conductor 10 described above, a thermosetting compound may be used instead of the photocurable compound used to form the resin. In the case of using a thermosetting compound, the thermosetting compound can be applied to the resin layer or the substrate and then heated and cured to obtain a resin. At this time, the thermosetting compound may be dissolved in a solvent. In this case, it is preferable to perform a drying step after coating. Alternatively, a resin obtained by curing a thermosetting compound by heating may be dissolved in a solvent, applied onto the barrier layer 15 or the substrate 13, and dried to obtain a resin.

  In the first or second embodiment, the conductive layer 14 may be a compressed layer. The manufacturing method of the said compression layer is as follows. That is, first, the conductive particles 11 are placed on the substrate. At this time, it is preferable that an anchor layer for fixing the conductive powder on the substrate is provided in advance on the substrate. If an anchor layer is provided in advance, the conductive particles 11 can be firmly fixed on the substrate. The conductive particles 11 can be easily placed. As said anchor layer, a polyurethane etc. are used suitably, for example.

  Then, the conductive particles 11 on the substrate are compressed toward the substrate side to form a compressed layer. This compression can be performed by a sheet press, a roll press or the like.

  Next, a photocurable compound is applied on one surface of the compression layer. At this time, a part of the photocurable compound will penetrate into the compressed layer. Thereafter, the barrier layer 15 is formed in the same manner as in the first or second embodiment. Finally, the base 13 is provided on the photocurable compound, and the photocurable compound is cured by irradiating with high energy rays. As a result, the transparent conductor of the present invention can be obtained.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

(Preparation of conductive powder)
An aqueous solution prepared by dissolving 19.9 g of indium chloride tetrahydrate (manufactured by Kanto Chemical Co., Ltd.) and 2.6 g of stannic chloride (manufactured by Kanto Chemical Co., Ltd.) in 980 g of water and aqueous ammonia (manufactured by Kanto Chemical Co., Ltd.) A white diluted product (co-precipitate) was produced by mixing with the one diluted twice.

  The liquid containing the generated precipitate was subjected to solid-liquid separation with a centrifuge to obtain a solid. This was further poured into 1000 g of water, dispersed with a homogenizer, and solid-liquid separation was performed with a centrifuge. After repeating dispersion and solid-liquid separation five times, the solid was dried and heated at 600 ° C. for 1 hour in a nitrogen atmosphere to obtain ITO powder (conductive powder).

Example 1
One side of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Ltd., thickness 100 μm) is subjected to corona treatment, and then a SiO ₂ layer is formed with a thickness of 50 nm by RF sputtering to form a barrier layer did.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of the ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, average 50 vinyl groups per molecule, and average 25 groups of triethoxysilane), 25 parts by mass of 2-hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 25 parts by mass of urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-512) And 1 part by mass of a UV polymerization initiator (Ciba Specialty Chemicals, trade name: IRGACURE907) and 50 parts by mass of methyl ethyl ketone (MEK) were mixed to obtain a paste. This was formed by spin coating so that the film thickness after evaporation of MEK was 20 μm on the upper surface of the barrier layer. Furthermore, the conductive layer was formed and the transparent conductor A was obtained by performing UV irradiation which used this as a light source the high pressure mercury lamp of 3000 mJ / cm < ² > of integrated illumination intensity in nitrogen atmosphere.

(Example 2)
One side of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Ltd., thickness 100 μm) is subjected to corona treatment, and then a SiO ₂ layer is formed with a thickness of 50 nm by RF sputtering to form a barrier layer and did.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 30 parts by mass of hydroxy-3-phenoxypropyl acrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 5 parts by mass of dipentaerythritol hexaacrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name A-DPH) And 15 parts by mass of a urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-100H), 1 part by weight of a UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE 907), 50 parts by mass of methyl ethyl ketone (MEK) was mixed to obtain a paste. This was formed by spin coating so that the film thickness after evaporation of MEK was 20 μm on the upper surface of the barrier layer. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance of 3000 mJ / cm ^{2 in} a nitrogen atmosphere to form a conductive layer, whereby a transparent conductor B was obtained.

(Example 3)
Corona treatment was performed on both sides of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Ltd., thickness 100 μm), and then a SiO ₂ layer was formed on both sides with a thickness of 50 nm by an RF sputtering method. did.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 -25 parts by mass of hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 25 parts by mass of urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-512) , 1 part by mass of UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE907) and 50 parts by mass of methyl ethyl ketone (MEK) were mixed to obtain a paste. This was formed by spin coating so that the film thickness after evaporation of MEK was 20 μm on the upper surface of one barrier layer. Furthermore, the conductive layer was formed and the transparent conductor C was obtained by performing UV irradiation which uses this as a light source for the high intensity | strength mercury lamp of 3000 mJ / cm < ² > of accumulated illumination intensity in nitrogen atmosphere.

Example 4
One side of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Limited, thickness 100 μm) is subjected to corona treatment, and then 50 volumes of SiO ₂ powder (product name: Aerosil 300 manufactured by Nippon Aerosil Co., Ltd.) is used. % Acrylic polymer (average molecular weight about 50,000, containing 50 average vinyl groups and 25 average triethoxysilanes per molecule) and 2-hydroxy-3-phenoxypropyl acrylate (Shin Nakamura Chemical Co., Ltd.) 10 parts by mass made by company, product name: 702A), 10 parts by mass dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name A-DPH), and urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) Product name: UA-100H) 30 parts by mass and UV polymerization initiator (Ciba Specialty Ke) Karuzu Co., Ltd., trade name: IRGACURE907) and 1 part by weight, and methyl ethyl ketone (MEK) 50 parts by weight and, by mixing the paste. This was spin-coated on the surface subjected to corona treatment so that the film thickness after volatilization of MEK was 5 μm. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance of 200 mJ / cm ^{2 in} a nitrogen atmosphere, thereby forming a barrier layer.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 30 parts by mass of hydroxy-3-phenoxypropyl acrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 5 parts by mass of dipentaerythritol hexaacrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name A-DPH) And 15 parts by mass of a urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-100H), 1 part by weight of a UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE 907), 50 parts by mass of methyl ethyl ketone (MEK) was mixed to obtain a paste. This was formed by spin coating so that the film thickness after evaporation of MEK was 20 μm on the upper surface of the barrier layer. Furthermore, the conductive layer was formed and the transparent conductor D was obtained by performing UV irradiation which uses this as a light source for the high intensity | strength mercury lamp of 3000 mJ / cm < ² > of accumulated illumination intensity in nitrogen atmosphere.

(Example 5)
One side of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Ltd., thickness 100 μm) was subjected to corona treatment, and then an SiO ₂ layer was formed to a thickness of 50 nm by RF sputtering. Further, an acrylic polymer containing 50% by volume of SiO ₂ powder (manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil 300) (average molecular weight of about 50,000, containing an average of 50 vinyl groups per molecule and an average of 25 triethoxysilane groups) 50 Parts by mass, 10 parts by mass of 2-hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A), and dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name A- DPH) 10 parts by mass, urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-100H), and UV polymerization initiator (Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE 907) 1 part by mass and 50 parts by mass of methyl ethyl ketone (MEK) are mixed to form a paste. It was. This was formed by spin coating so that the film thickness after evaporation of MEK was 5 μm on the upper surface of the SiO ₂ layer. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance amount of 1000 mJ / cm ^{2 in} a nitrogen atmosphere, thereby forming a barrier layer.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 -25 parts by mass of hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 25 parts by mass of urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-512) , 1 part by mass of UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE907) and 50 parts by mass of methyl ethyl ketone (MEK) were mixed to obtain a paste. This was formed by spin coating so that the film thickness after evaporation of MEK was 20 μm on the surface opposite to the barrier layer. Furthermore, the conductive layer was formed and the transparent conductor E was obtained by performing UV irradiation which uses a high pressure mercury lamp with an integrated illumination amount of 3000 mJ / cm ^{2 as} a light source in a nitrogen atmosphere.

(Example 6)
A corona treatment was performed on both sides of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Ltd., thickness: 100 μm), and then a SiO ₂ layer having a thickness of 50 nm was formed on one side by RF sputtering. Next, an acrylic polymer containing 50% by volume of SiO ₂ powder (manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil 300) (average molecular weight of about 50,000, an average of 50 vinyl groups per molecule, and an average of 25 triethoxysilane groups) 50 parts by mass, 10 parts by mass of 2-hydroxy-3-phenoxypropyl acrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name: 702A), and dipentaerythritol hexaacrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name A) -DPH) 10 parts by mass, urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-100H), and UV polymerization initiator (Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE 907) ) 1 part by mass and 50 parts by mass of methyl ethyl ketone (MEK) are mixed to form a paste. It was. This was formed by spin coating so that the film thickness after evaporation of MEK was 5 μm on the other surface of the SiO ₂ layer. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance amount of 1000 mJ / cm ^{2 in} a nitrogen atmosphere, thereby forming a barrier layer.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 -25 parts by mass of hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 25 parts by mass of urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-512) , 1 part by mass of UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE907) and 50 parts by mass of methyl ethyl ketone (MEK) were mixed to obtain a paste. This was formed by spin coating so that the film thickness after evaporation of MEK was 20 μm on the surface of the SiO ₂ layer. Furthermore, the conductive layer was formed and the transparent conductor F was obtained by performing UV irradiation which uses a high pressure mercury lamp with an integrated illumination amount of 3000 mJ / cm ^{2 as} a light source in a nitrogen atmosphere.

(Example 7)
A corona treatment was performed on both sides of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Ltd., thickness: 100 μm), and then a SiO ₂ layer was formed on both sides with a thickness of 50 nm by RF sputtering. Next, an acrylic polymer containing 50% by volume of SiO ₂ powder (manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil 300) (average molecular weight of about 50,000, an average of 50 vinyl groups per molecule, and an average of 25 triethoxysilane groups) 50 parts by mass, 10 parts by mass of 2-hydroxy-3-phenoxypropyl acrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name: 702A), and dipentaerythritol hexaacrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name A) -DPH) 10 parts by mass, urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-100H), and UV polymerization initiator (Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE 907) ) 1 part by mass and 50 parts by mass of methyl ethyl ketone (MEK) are mixed to form a paste. It was. This was formed by spin coating so that the film thickness after evaporation of MEK was 5 μm on one surface of the substrate on which the SiO ₂ layer was formed. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance amount of 1000 mJ / cm ^{2 in} a nitrogen atmosphere, thereby forming a barrier layer.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 -25 parts by mass of hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 25 parts by mass of urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-512) , 1 part by mass of UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE907) and 50 parts by mass of methyl ethyl ketone (MEK) were mixed to obtain a paste. This was formed by spin coating so that the SiO ₂ layer opposite to the surface on which the SiO ₂ powder-containing paste was applied was exposed so that the film thickness after MEK volatilization was 20 μm. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance of 3000 mJ / cm ^{2 in} a nitrogen atmosphere, whereby a conductive layer was formed, and a transparent conductor G was obtained.

(Comparative Example 1)
One side of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Limited, thickness 100 μm) was subjected to corona treatment.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 -25 parts by mass of hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 25 parts by mass of urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-512) , 1 part by mass of UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE907) and 50 parts by mass of methyl ethyl ketone (MEK) were mixed to obtain a paste. This was formed by spin coating so that the film thickness after MEK volatilization was 20 μm on the upper surface of the corona-treated surface. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance of 3000 mJ / cm ^{2 in} a nitrogen atmosphere to form a conductive layer, and a transparent conductor H was obtained.

(Comparative Example 2)
One side of a 50 mm square polyethylene terephthalate (PET) film (substrate, manufactured by Teijin Limited, thickness 100 μm) was subjected to corona treatment.

Next, 50 parts by mass of an acrylic polymer containing 40% by volume of ITO powder (average particle size 30 nm) (average molecular weight of about 50,000, containing 50 average vinyl groups and 25 average triethoxysilane per molecule), 2 30 parts by mass of hydroxy-3-phenoxypropyl acrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) and 5 parts by mass of dipentaerythritol hexaacrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name A-DPH) And 15 parts by mass of a urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-100H), 1 part by weight of a UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE 907), 50 parts by mass of methyl ethyl ketone (MEK) was mixed to obtain a paste. This was formed by spin coating so that the film thickness after MEK volatilization was 20 μm on the upper surface of the corona-treated surface. Further, this was subjected to UV irradiation using a high pressure mercury lamp having an integrated illuminance of 3000 mJ / cm ^{2 in} a nitrogen atmosphere to form a conductive layer, whereby a transparent conductor I was obtained.

[Evaluation methods]
(Evaluation of resistance of transparent conductor film)
The transparent conductors A to I obtained as described above were evaluated for electrical resistance as follows. That is, for a predetermined measurement point of the transparent conductor obtained as described above, the value of electric resistance is measured with a four-terminal four-probe surface resistance measuring instrument (MCP-T600 manufactured by Mitsubishi Chemical Corporation), The measured value was taken as the initial electrical resistance value. Thereafter, the transparent conductor was left in an environment of 60 ° C. and 95% RH for 1000 hours. After the transparent conductor was lowered to room temperature, the electric resistance value was again measured at a measurement point determined before humidification. Was measured and used as the electric resistance value after humidification. And the following formula:
Rate of change = rate of change based on the electric resistance value after humidification / initial electric resistance value. The obtained results are shown in Table 1.

  As is clear from Table 1, Examples 1 to 7 using a barrier layer have a smaller change in electric resistance value than Comparative Examples 1 and 2 not using a barrier layer, and can sufficiently suppress an increase in electric resistance value. I found out. From the above results, it was confirmed that the transparent conductive material of the present invention can sufficiently suppress an increase in electrical resistance value and a change with time even under a high humidity environment.

It is a schematic cross section which shows 1st Embodiment of the transparent conductor of this invention. It is a schematic cross section which shows 2nd Embodiment of the transparent conductor of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10,20 ... Transparent conductor, 11 ... Conductive particle, 12 ... Resin, 13 ... Base | substrate, 14 ... Conductive layer, 15,16 ... Barrier layer.

Claims (4)

A substrate;
A conductive layer containing conductive particles and a resin;
A barrier layer containing a metal or an inorganic compound;
With
A transparent conductor, wherein the barrier layer is provided between at least one of the base and the conductive layer and on the opposite side of the base from the conductive layer.   The barrier layer is provided between the substrate and the conductive layer, the barrier layer is a conductive continuous layer containing a single metal or a conductive oxide, and the conductive particles in the conductive layer The transparent conductor according to claim 1, wherein the barrier layer is in contact with the transparent conductor. The transparent conductor according to claim 1, wherein the barrier layer contains at least one inorganic compound selected from the group consisting of SiO ₂ , Al ₂ O ₃ , TiO ₂ , ZnO, or ZrO ₂ . The transparent conductor according to any one of claims 1 to 3, wherein the barrier layer is provided between the base and the conductive layer and on the opposite side of the conductive layer with respect to the base.

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