JP2011171041A - Transparent conductor and conductive film for transfer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent conductor having a low electric resistance value, having a high durability, and manufactured with a low cost; a conductive film for transfer suitably used for manufacturing the transparent conductor; and a method of manufacturing the transparent conductor using the conductive film for transfer. <P>SOLUTION: The transparent conductor 20 includes a base material 6, an adhesive layer 5 on the base material 6, and a transparent conductive layer 3 on the adhesive layer 5, wherein the adhesive layer 5 is a hardened material layer at least containing a curable compound, the conductive layer 3 comprises a compressed layer with at least two layers of conductive particulates including a surface layer 3a located on a surface opposite from the base material 6 and an inner layer 3b in contact with the adhesive layer 5, the compressed layer with at least two layers of conductive particulates is constituted by the conductive particulates having different average particle diameters, respectively, and the surface layer 3a is constituted by the conductive particulates having the smallest average particle diameter among the compressed layer with at least two layers of conductive particulates. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a transparent conductor and a transfer conductive film used for producing the transparent conductor.

  Transparent electrodes are used in display devices such as a liquid crystal display (LCD), a plasma display panel (PDP), an electroluminescence panel (organic EL, inorganic EL), a touch panel, and an electrochromic element. Such a transparent electrode is often composed of a transparent conductor composed of a base material and a transparent conductive layer formed on the base material. The transparent conductor can also be used as a transparent electromagnetic wave shielding film.

  Conventionally, a transparent conductive film has been mainly produced by a sputtering method. The sputtering method is excellent in that a conductive film having a low surface electric resistance can be formed even with a certain large area. However, there is a drawback that the apparatus is large and the film forming speed is slow.

  Attempts have also been made to produce a transparent conductive film by a coating method. In the conventional coating method, a conductive coating material in which conductive fine particles are dispersed in a binder resin is applied on a substrate, dried and cured to form a conductive film. The coating method has an advantage that a conductive film having a large area can be easily formed, the apparatus is simple, the productivity is high, and the conductive film can be manufactured at a lower cost than the sputtering method. In the coating method, when conductive fine particles come into contact with each other, an electric path is formed and conductivity is expressed. However, the conductive film produced by the conventional coating method has a drawback that the contact between the conductive fine particles is insufficient due to the presence of the binder resin, and the resulting conductive film has a high electrical resistance value (inferior in conductivity). Yes, its use is limited.

  As a coating method not using a binder resin, for example, JP-A-8-199096 discloses a binder comprising a tin-doped indium oxide (ITO) powder, a solvent, a coupling agent, a metal organic acid salt or an inorganic acid salt. A method of applying a conductive film-forming coating material not included on a glass plate and firing at a temperature of 300 ° C. or higher is disclosed. In this method, since no binder is used, the electric resistance value of the conductive film is lowered. However, firing at a high temperature is necessary, and the base material is limited to a material that can withstand high temperatures such as a glass plate.

  Japanese Patent Application Laid-Open No. 6-103839 discloses a method for producing a transparent conductive substrate by transfer.

  Japanese Patent Application Laid-Open No. 2002-347150 discloses a conductive film for transfer for forming a transparent conductive layer on the surface of a target object. The conductive layer of the transfer conductive film is formed by compressing conductive fine particles. It is disclosed that a transparent conductive layer is formed on the surface of a target object using this transfer conductive film.

  JP-A-2007-253425, JP-A-2007-257963, and JP-A-2007-257964 disclose a conductive film for transfer for forming a transparent conductive layer on the surface of a target object. ing. The conductive layer of the transfer conductive film is formed by compressing conductive fine particles. An object provided with a transparent conductive layer using the transfer conductive film is disclosed.

  JP-A-2006-185865 discloses a transparent conductor comprising a base material, a conductive layer, and an intermediate layer containing a resin and a filler provided between the base material and the conductive layer. ing. It is also disclosed that the production of the transparent conductor may be performed in a transfer manner (paragraphs [0060] to [0063]). However, the conductive layer is formed by applying conductive powder and a binder resin.

  Japanese Patent Application Laid-Open No. 2001-328192 discloses a functional film in which a multilayer functional layer capable of expressing various functions of at least two layers including a conductive layer is provided on a support, although not intended for transfer. It is disclosed.

  By the way, a panel switch such as a touch panel generally includes a pair of transparent electrodes facing each other and a spacer sandwiched between the pair of transparent electrodes. When one of the transparent electrodes is pressed with a finger or a pen, The transparent electrode comes into contact with the other transparent electrode and energization occurs, whereby the position of the contact point is detected. If the touch panel is used repeatedly, the conductive layer of the transparent conductor will be cracked or scraped by repeated pressing or sliding with a finger or pen during pressing, resulting in changes in electrical resistance, variations, and deterioration of linearity. Occur.

  Japanese Patent Application Laid-Open No. 8-64067 discloses a pen input touch panel having a transparent conductive layer formed by a sputtering method. Japanese Patent Application Laid-Open No. 2001-283644 discloses a transparent conductive film and a touch panel having a transparent conductive layer formed by a sputtering method.

  JP-A-6-202789 discloses that at least one electrode surface is coated with an insulating chain organic polymer compound having a functional group capable of binding to an electrode material in order to improve durability in repeated use. A drawing pad is disclosed. However, when the electrode surface is coated with an insulating organic polymer compound, the surface resistance value increases, and the contact resistance value when the opposing transparent electrodes come into contact with each other increases. Therefore, energization due to contact between the electrodes does not occur unless the pressure during pressing is increased.

JP-A-8-199096 JP-A-6-103839 JP 2002-347150 A JP 2007-253425 A JP 2007-257963 A JP 2007-257964 A JP 2006-185865 A JP 2001-328192 A JP-A-8-64067 JP 2001-283644 A JP-A-6-202789

  An object of the present invention is to provide a transparent conductor having a low electric resistance value, excellent in durability and capable of being manufactured at low cost. Moreover, the objective of this invention is providing the electroconductive film for transfer which can be used suitably in order to manufacture the said transparent conductor. Furthermore, the objective of this invention is providing the method of manufacturing the said transparent conductor using the said conductive film for transcription | transfer.

The present invention includes the following inventions.
(1) A transparent conductor having a base material, an adhesive layer on the base material, and a transparent conductive layer on the adhesive layer,
The adhesive layer is a cured product layer of an adhesive composition containing at least a curable compound,
The conductive layer comprises a compressed layer of at least two conductive fine particles including a surface layer located on the surface opposite to the substrate and an inner layer in contact with the adhesive layer,
The compressed layer of at least two layers of conductive fine particles is composed of conductive fine particles having different average particle diameters, respectively.
The said surface layer is a transparent conductor comprised from the conductive fine particle which has the smallest average particle diameter among the compression layers of the said at least 2 layer of conductive fine particle.

(2) The transparent conductor according to (1) above, wherein the conductive fine particles constituting the surface layer have an average particle diameter of 10 to 20 nm.

(3) The transparent conductor according to (1) or (2), wherein the surface layer has a thickness of 0.2 to 0.7 μm.

(4) The transparent conductor according to any one of (1) to (3), wherein the conductive fine particles constituting the inner layer have an average particle size of 25 to 80 nm.

(5) The transparent conductor according to any one of (1) to (4), wherein the inner layer has a thickness of 0.3 to 1.3 μm.

(6) The conductive fine particles include indium oxide, tin-doped indium oxide (ITO), gallium-doped indium oxide, zinc-doped indium oxide, tin oxide, antimony-doped tin oxide (ATO), fluorine-doped tin oxide (FTO), and oxidation. Conductive inorganic fine particles selected from the group consisting of zinc, aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), fluorine-doped zinc oxide, indium-doped zinc oxide, boron-doped zinc oxide, and cadmium oxide, The transparent conductor according to any one of (1) to (5).

(7) A conductive film for transfer comprising at least a support, a transparent conductive layer that is peelable from the support on the support, and an adhesive layer on the transparent conductive layer,
The adhesive layer is made of an adhesive composition containing at least a curable compound,
The conductive layer comprises a compressed layer of at least two conductive fine particles including a layer in contact with the support and a layer in contact with the adhesive layer,
The compressed layer of at least two layers of conductive fine particles is composed of conductive fine particles having different average particle diameters, respectively.
The conductive film for transfer, wherein the layer in contact with the support is composed of conductive fine particles having the smallest average particle diameter among the compressed layers of the at least two conductive fine particles.

(7-2) The transparent conductor according to (7) above, wherein an average particle diameter of the conductive fine particles constituting the layer in contact with the support is 10 to 20 nm.

(7-3) The transparent conductor according to (7) or (7-2), wherein the layer in contact with the support has a thickness of 0.2 to 0.7 μm.

(7-4) The average particle diameter of the conductive fine particles constituting the layer in contact with the adhesive layer is 25 to 80 nm, according to any one of (7) to (7-3) above. Transparent conductor.

(7-5) The transparent conductor according to any one of (7) to (7-4), wherein the layer in contact with the adhesive layer has a thickness of 0.3 to 1.3 μm.

(7-6) The conductive fine particles include indium oxide, tin-doped indium oxide (ITO), gallium-doped indium oxide, zinc-doped indium oxide, tin oxide, antimony-doped tin oxide (ATO), and fluorine-doped tin oxide (FTO). Conductive inorganic fine particles selected from the group consisting of zinc oxide, aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), fluorine-doped zinc oxide, indium-doped zinc oxide, boron-doped zinc oxide, and cadmium oxide The transparent conductor according to any one of (7) to (7-5) above.

The compressed layer of conductive fine particles can be obtained by compressing a conductive fine particle-containing layer formed by applying and drying a liquid in which conductive fine particles are dispersed on a support. In each compressed layer, conductive fine particles having a desired average particle diameter are used. The compressed layer of conductive fine particles is preferably obtained by compressing with a compressive force of 44 N / mm ² or more. Moreover, it is preferable that it was obtained by compressing at normal temperature (15-40 degreeC). A transparent conductive layer having a uniform thickness is formed.

  When the conductive film for transfer is produced, the conductive fine particle dispersion may contain a small amount of resin, but preferably does not contain a resin. When the dispersion liquid of the conductive fine particles contains a resin, the content of the resin is expressed by volume, and when the volume of the conductive fine particles is 100, for example, the volume is less than 25, preferably less than 19. Volume, more preferably less than 3.7. When the conductive fine particle-containing layer is compressed, the resin is not contained, or even if it is contained in a small amount, the contact point between the conductive fine particles is increased after compression, and the film strength of the conductive layer is increased. As it increases, the conductivity becomes good.

  There is a gap between the conductive fine particles in the compressed layer of the conductive fine particles. This adhesive component of the adhesive layer formed on the uppermost compression layer is impregnated in this void. The adhesive layer is formed by coating on the uppermost compression layer after the compression layer of the conductive fine particles is formed (after the compression operation). Since the adhesive component impregnated in the transfer is cured, the film strength of the conductive layer is further increased. In addition, the adhesion between the cured adhesive layer and the conductive layer is also improved.

(8) A method for producing the transparent conductor according to (1) above,
The conductive film for transfer described in (7) above is attached to the surface of the base material with the support on the outside via the adhesive layer of the film, and the adhesive layer is attached after the application. A method for producing a transparent conductor, comprising curing and then peeling the support.

  The curing operation is performed according to the curable compound of the adhesive layer. That is, in the case of a thermosetting compound, it is cured by heating. In the case of an active energy ray-curable compound, it is cured by irradiation with an active energy ray.

  The irradiation with the active energy ray is preferably performed from the substrate side. Since active energy rays are absorbed by the conductive layer (compressed layer of conductive fine particles), it is preferable to irradiate active energy rays not from the support side but from the base material side. The adhesive layer is cured by irradiation with active energy rays, and the adhesive component impregnated in the conductive layer is also cured. Thereby, the film strength of the conductive layer is further improved, and the haze value of the conductive layer is also improved.

  Thus, the transparent conductor of the present invention can be obtained by transferring the conductive layer of the transfer conductive film to the substrate surface via the adhesive layer using the transfer conductive film of the present invention. it can.

  In the present invention, “a transparent conductive layer that can be peeled off from the support” or “a transparent conductive layer that can be peeled off from the support” means that the support and the transparent conductive layer are peelable from each other. means. When the conductive film for transfer of the present invention is actually used, the support is often peeled off from the conductive layer attached on the surface of the substrate via the adhesive layer.

  In the conductive film for transfer of the present invention, the conductive film for transfer serves to fix the conductive fine particles on the support during the production of the conductive film for transfer, and adheres during transfer of the conductive layer onto the substrate. If the agent layer is cured, the support is preferably provided with an anchor layer on the surface in order to facilitate the peeling of the conductive layer from the support. In such a case, in the present invention, the support including the anchor layer is referred to as a support.

  According to the transparent conductor of the present invention, as described above, the transparent conductive layer is composed of a compressed layer of at least two conductive fine particles including a surface layer and an internal layer, and the surface layer includes the at least two layers. Among the conductive fine particle compressed layers, the conductive fine particles have the smallest average particle diameter. As described above, since the surface layer composed of the conductive fine particles having the smallest average particle diameter is arranged on the outermost surface of the transparent conductive layer, the surface roughness of the conductive layer is suppressed to be small, and the conductive layer is repeatedly conductive. Generation of cracks and scraping of the layer can be prevented, and sufficient durability of the transparent conductor can be obtained. In addition, an inner layer made of conductive fine particles having an average particle size larger than the average particle size of the conductive fine particles constituting the surface layer is disposed on the inner side closer to the adhesive layer than the surface layer. Therefore, conductive performance is ensured, and the surface resistance value of the transparent conductor can be reduced. Thus, according to the present invention, a transparent conductor having a small surface resistance value and sufficient durability is provided.

  Moreover, according to this invention, the electroconductive film for transfer which can be used suitably in order to manufacture the said transparent conductor is provided.

  The conductive film for transfer of the present invention can be produced at a low cost by a simple operation of applying a dispersion of conductive fine particles, forming a compressed layer of conductive fine particles by compression, and then applying and forming an adhesive layer. it can. A transparent conductive layer having a uniform thickness and a low electrical resistance value is formed.

  Furthermore, according to the present invention, there is provided a method for producing the transparent conductor of the present invention using the conductive film for transfer of the present invention.

  The transparent conductor of the present invention is a liquid crystal display (LCD), a plasma display panel (PDP), an electroluminescence panel (organic EL, inorganic EL), a touch panel, an electrochromic device, for transparent electrodes, for antistatic purposes, and for electromagnetic wave shielding It can be applied to display devices such as electronic paper and antennas.

  Since the transparent conductor of the present invention has a small surface resistance and sufficient durability, it is particularly suitably used for a panel switch such as a touch panel. When applied to a panel switch such as a touch panel, the input load (pressing) is maintained at a good level.

It is sectional drawing which shows an example of the electroconductive film for transfer of this invention. It is sectional drawing which shows an example of the transparent conductor of this invention.

(1): Support
(1a): Support body
(1b): Anchor layer
(2a): Conductive fine particles (particles with the smallest average particle size)
(2b): Conductive fine particles
(3): Transparent conductive layer
(3a): Transparent conductive layer (layer consisting of conductive fine particles with minimum average particle diameter)
(3b): Transparent conductive layer
(5): Uncured adhesive layer
(10): Conductive film for transfer
(6): Base material
(5): Hardened adhesive layer
(20): Transparent conductor

  First, the conductive film for transfer of the present invention (hereinafter also simply referred to as a conductive film) will be described.

  FIG. 1 is a cross-sectional view showing a layer configuration example of a transfer conductive film. In the conductive film of FIG. 1, the support body (1a) and the anchor layer (1b) provided on one surface of the body (1a) are transparent on the anchor layer (1b) of the support body (1). A conductive layer (3) is formed, and an adhesive layer (5) is formed on the transparent conductive layer (3). The transparent conductive layer (3) includes a layer (3a) in contact with the support (1) and a layer (3b) in contact with the layer (3a) and in contact with the adhesive layer (5). It consists of a compressed layer of two conductive fine particles, and is provided so as to be peelable from the support (1). In order to protect the adhesive layer surface until use, a release film (not shown) may be provided on the adhesive layer (5).

  The term “transparent” in the present invention means that visible light is transmitted, and even if light is scattered to some extent, it is included in the concept of transparency. Regarding the degree of light scattering, the level required varies depending on the use of the conductive film for transfer, that is, the use of the target object (substrate) on which the conductive layer is transferred, and there is light scattering that is generally said to be translucent. Cases are also included in the concept of transparency.

  In the present invention, as the support body (1a), a flexible resin film that does not crack even if the compression force in the compression step described later is increased is suitable. In the present invention, in the production of the conductive film for transfer, since there is no pressurizing step or baking step at high temperature, a resin film can be used as a support. Examples of the resin film include polyester films such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyolefin films such as polyethylene and polypropylene, polycarbonate films, acrylic films, and norbornene films.

  The anchor layer (1b) has a certain degree of hardness and cushioning properties in order to form and hold a conductive layer (3) composed of a compressed layer of conductive fine particles on the support (1). On the other hand, the anchor layer (1b) is preferably relatively hard because it is peeled off between the anchor layer (1b) and the conductive layer (3) during transfer, and the support body (1a) The adhesion with the anchor layer (1b) is preferably higher than the adhesion between the anchor layer (1b) and the conductive layer (3). The anchor layer (1b) is preferably selected from silicone resin, acrylic resin, urethane resin, vinyl chloride resin, etc., and a resin solution is applied to the support body (1a) and dried. Application | coating in this case can be performed by a well-known method. For example, it can be performed by a coating method such as an extrusion nozzle method, a blade method, a knife method, a bar coating method, a kiss coating method, a gravure roll method, a dipping method, a reverse roll method, a direct roll method, a curtain method, or a squeeze method.

  Although the thickness of an anchor layer (1b) is not limited, For example, what is necessary is just to be about 0.5-5 micrometers. When the thickness of the anchor layer (1b) is less than 0.5 μm, it is difficult to obtain the effect of firmly fixing the conductive particles on the support (1). On the other hand, when the thickness is greater than 5 μm, a curable resin is used. In addition, there is a possibility of insufficient curing during irradiation of active energy rays in the transfer operation. When the anchor layer (1b) is completely cured, the hardness becomes higher. Therefore, the anchor layer (1b) is easily peeled off between the anchor layer (1b) and the conductive layer (3).

  A transparent conductive layer (3) is formed on the anchor layer (1b) of the support (1) using a dispersion of conductive fine particles. The transparent conductive layer (3) consists of a layer (3a) in contact with the support (1) and a layer (3b) in contact with the layer (3a) and in contact with the adhesive layer (5). It consists of a compressed layer of conductive fine particles.

  The conductive fine particles are preferably composed of a transparent conductive oxide material. The transparent conductive oxide material is not particularly limited as long as it has transparency and conductivity. For example, indium oxide, or indium oxide, tin, zinc, tellurium, silver, gallium, zirconium, hafnium, and magnesium. One doped with at least one element selected from tin; or tin oxide or tin oxide doped with at least one element selected from the group consisting of antimony, zinc and fluorine; zinc oxide, or A zinc oxide doped with at least one element selected from the group consisting of aluminum, gallium, indium, boron, fluorine, and manganese; a titanium oxide doped with niobium or tantalum.

  Suitable conductive fine particles include, for example, indium oxide, tin-doped indium oxide (ITO), gallium-doped indium oxide, zinc-doped indium oxide, tin oxide, antimony-doped tin oxide (ATO), fluorine-doped tin oxide (FTO), Conductive inorganic fine particles such as zinc oxide, aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), fluorine-doped zinc oxide, indium-doped zinc oxide, boron-doped zinc oxide, and cadmium oxide are used. ITO is preferable in that it provides better conductivity. Or what coated inorganic material, such as ATO and ITO, on the surface of fine particles which have transparency, such as barium sulfate, can also be used.

  The layer (3a) in contact with the support (1) is a surface layer (3a) to be exposed after transfer because the support (1) is peeled off during the transfer operation to the target object.

  The average particle diameter of the conductive fine particles (2a) for the surface layer (3a) is preferably 10 nm to 20 nm. When the average particle size is less than 10 nm, the conductivity of the transparent conductor tends to be insufficient as compared with the case where the average particle size is 10 nm or more. On the other hand, when the average particle diameter exceeds 20 nm, the surface smoothness of the surface layer (3a) is reduced compared to the case where the average particle diameter is in the above range, and sufficient when the transparent conductor is used as a touch panel. There is a tendency that the durability is not obtained. More preferable average particle diameter of the conductive fine particles (2a) is, for example, an upper limit of 17 nm and a lower limit of 12 nm. Moreover, you may use the particle | grains surface-treated with the silane coupling agent. The average particle size can be measured using, for example, a transmission electron microscope (JIS 7804).

The specific surface area of the surface layer (3a) for the conductive fine particles (2a) is preferably 52m ² / g~63m ² / g. When the specific surface area of the conductive fine particles is less than 52 m ² / g, the surface smoothness of the surface layer (3a) is reduced as compared with the case where the specific surface area is in the above range, and the transparent conductor was used as a touch panel. In some cases, sufficient durability tends not to be obtained. On the other hand, when the specific surface area exceeds 63 m ² / g, there is a tendency that the conductivity of the transparent conductor cannot be sufficiently obtained as compared with the case where the specific surface area is in the above range. More preferable specific surface area of the conductive fine particles (2a) is, for example, an upper limit of 60 m ² / g and a lower limit of 55 m ² / g. The specific surface area referred to here is based on the BET method, and is a value measured after vacuum drying the sample at 300 ° C. for 30 minutes using a specific surface area measuring device (model: NOVA2000, manufactured by Cantachrome). .

  The film thickness of the surface layer (3a) is preferably 0.2 μm to 0.7 μm. When the film thickness is less than 0.2 μm, the effect of improving the surface smoothness of the surface layer (3a) is small, and when the transparent conductor is used as a touch panel, sufficient durability tends not to be obtained. On the other hand, when the film thickness exceeds 0.7 μm, the conductivity of the transparent conductor tends to be insufficient. More preferable film thickness of the surface layer (3a) is, for example, an upper limit of 0.5 μm and a lower limit of 0.3 μm.

  The layer (3b) in contact with the layer (3a) in contact with the support (1) [that is, the surface layer (3a)] and in contact with the adhesive layer (5) is cured after transfer to the target object. It is the inner layer (3b) that should be positioned closest to the target object via the adhesive layer (5).

  The average particle diameter of the conductive fine particles (2b) for the inner layer (3b) is preferably 25 nm to 80 nm. When the average particle size is less than 25 nm, the conductivity of the transparent conductor tends to be insufficient as compared with the case where the average particle size is 25 nm or more. On the other hand, when the average particle size exceeds 80 nm, light scattering increases in the wavelength region of visible light and the haze value tends to increase as compared with the case where the average particle size is in the above range. More preferable average particle diameter of the conductive fine particles (2b) is, for example, an upper limit of 50 nm and a lower limit of 30 nm.

The specific surface area of the inner layer (3b) for the electrically conductive fine particles (2b) is preferably 10m ² / g~48m ² / g. When the specific surface area of the conductive fine particles is less than 10 m ² / g, light scattering increases in the visible light wavelength region and the haze value tends to increase as compared with the case where the specific surface area is in the above range. On the other hand, when the specific surface area exceeds 48 m ² / g, there is a tendency that the conductivity of the transparent conductor cannot be sufficiently obtained as compared with the case where the specific surface area is in the above range. More preferable specific surface area of the conductive fine particles (2b) is, for example, an upper limit of 45 m ² / g and a lower limit of 25 m ² / g.

  The film thickness of the inner layer (3b) is preferably 0.3 μm to 1.3 μm. If the film thickness is less than 0.3 μm, the conductivity of the transparent conductor tends to be insufficient. On the other hand, when the film thickness exceeds 1.3 μm, the light transmittance of the transparent conductor tends to decrease. A more preferable thickness of the inner layer (3b) is, for example, an upper limit of 0.7 μm and a lower limit of 0.5 μm.

  In FIG. 1, the transparent conductive layer (3) is in contact with the layer (3a) [that is, the surface layer (3a)] in contact with the support (1), the layer (3a), and the adhesive layer (5 ) Is a two-layered form with the layer (3b) [that is, the inner layer (3b)] in contact therewith. In the present invention, the transparent conductive layer (3) is not limited to the example of FIG. 1, and the transparent conductive layer (3) is in contact with the support (1) (3a) [that is, the surface layer (3a)] and the adhesive layer (5 ) Includes a layer composed of three layers, ie, a layer (3b) [that is, an inner layer (3b)] in contact with the intermediate layer and an intermediate layer located between them. Furthermore, a mode in which two or more intermediate layers are provided is also included.

  The average particle size of the conductive fine particles for the intermediate layer is larger than the average particle size of the conductive fine particles (2a) for the surface layer (3a). The average particle size of the conductive fine particles for the intermediate layer is preferably smaller than the average particle size of the conductive fine particles (2b) for the inner layer (3b). In order to satisfy these conditions, the average particle size of the conductive fine particles for the intermediate layer is preferably 20 nm to 25 nm, for example. When two or more intermediate layers are provided, the average particle diameter of the conductive fine particles constituting the intermediate layer is preferably increased sequentially from the surface layer (3a) side toward the inner layer (3b).

The specific surface area of the conductive fine particles for the intermediate layer is smaller than the specific surface area of the conductive fine particles (2a) for the surface layer (3a) and smaller than the specific surface area of the conductive fine particles (2b) for the inner layer (3b). Larger is preferred. So as to satisfy this condition, the specific surface area of the conductive fine particles for the intermediate layer is preferably, for example, 45m ² / g~85m ² / g. When two or more intermediate layers are provided, it is preferable that the specific surface area of the conductive fine particles constituting the intermediate layer be sequentially reduced from the surface layer (3a) side toward the inner layer (3b).

  The film thickness of the intermediate layer is not particularly limited and is preferably 0.2 μm to 0.4 μm, for example. When two or more intermediate layers are provided, the total film thickness is preferably in the above range.

  The average particle diameter, specific surface area, and film thickness of the conductive fine particles when the intermediate layer is provided may be appropriately determined with reference to the description of the surface layer (3a) and the inner layer (3b).

  In the present invention, a dispersion of conductive fine particles for the surface layer (3a), the inner layer (3b), and if necessary, for the intermediate layer is prepared.

  The dispersion medium for dispersing the conductive fine particles is not particularly limited, and various known liquids can be used. For example, as liquid, saturated hydrocarbons such as hexane, aromatic hydrocarbons such as toluene and xylene, alcohols such as methanol, ethanol, propanol and butanol, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, diisobutyl ketone, etc. Ketones, esters such as ethyl acetate and butyl acetate, ethers such as tetrahydrofuran, dioxane and diethyl ether, amides such as N, N-dimethylformamide, N-methylpyrrolidone (NMP) and N, N-dimethylacetamide And halogenated hydrocarbons such as ethylene chloride and chlorobenzene. Among these, polar liquids are preferable, and those having an affinity for water, such as alcohols such as methanol and ethanol, and amides such as NMP, have good dispersibility without using a dispersant. It is preferable. These liquids can be used singly or as a mixture of two or more. Moreover, a dispersing agent can also be used according to the kind of liquid.

  Water can also be used as a dispersion medium. When water is used, the surface of the support (1) (when no anchor layer is provided) or the anchor layer (1b) provided on the support body (1a) needs to be hydrophilic. Since the resin film and the anchor layer (resin layer) are usually hydrophobic, they easily repel water and it is difficult to obtain a uniform film. In such a case, it is necessary to mix alcohol with water, or to make the surface of the anchor layer hydrophilic by corona treatment or the like.

  The amount of the dispersion medium to be used is not particularly limited, and the dispersion liquid of the conductive fine particles may have a viscosity suitable for coating. For example, the amount is about 100 to 100,000 parts by weight of the liquid with respect to 100 parts by weight of the conductive fine particles. It is preferable to select appropriately according to the type of the conductive fine particles and the dispersion medium.

  The conductive fine particles may be dispersed in a dispersion medium by a known dispersion method. For example, it is dispersed by a sand grinder mill method. In dispersing, it is also preferable to use media such as zirconia beads in order to loosen the aggregation of the fine particles.

  In addition, in the dispersion liquid of the conductive fine particles, an additive may be further contained as necessary to the extent that the target performance is not impaired. Examples of the additive include a flame retardant, an ultraviolet absorber, a radical scavenger, a plasticizer, a binder, a coupling agent, a filler, a leveling agent, and a surfactant. For transparent electrode applications, low electrical resistance values are required, so these additives should be used in small amounts. For antistatic applications, these additives may provide additional performance.

  First, the prepared dispersion of conductive fine particles for the surface layer (3a) is applied and dried on the support (1) (anchor layer (1b)) to form a conductive fine particle-containing layer. The application of the fine particle dispersion is not particularly limited, and can be performed by a known method. For example, the fine particle dispersion can be performed by a coating method similar to the method described in the application of the anchor layer. The drying temperature depends on the type of dispersion medium used for dispersion, but is preferably about 10 to 150 ° C. If it is less than 10 ° C, condensation of moisture in the air tends to occur, and if it exceeds 150 ° C, the resin film support is deformed.

Thereafter, the conductive fine particle-containing layer for the surface layer (3a) is compressed by a sheet press, a roll press or the like to form a compressed layer (3a) of conductive fine particles. By compressing, the contact points between the conductive fine particles increase and the contact surface increases. For this reason, the coating strength increases and the electrical resistance value decreases. Excellent in conductivity, in order to obtain a conductive layer excellent in film strength, compression is preferably carried out at 44N / mm ² or more compression force, more preferably 135N / mm ² or more compression strength, 180 N / mm ² or more A compressive force is more preferable. Since the pressure resistance of the apparatus has to be increased as the compressive force is increased, generally a compressive force of up to 1000 N / mm ² is appropriate. Moreover, it is preferable to perform compression at normal temperature (15-40 degreeC). The roll temperature of the roll press machine is preferably normal temperature (15 to 40 ° C.).

  Next, a conductive fine particle dispersion for the inner layer (3b) is applied and dried on the compressed surface layer (3a) by the same method to form a conductive fine particle-containing layer. Thereafter, the conductive fine particle-containing layer for the inner layer (3b) is compressed by the same method to form a compressed layer (3b) of conductive fine particles.

  In the case of providing the intermediate layer, it is preferable to form the surface layer (3a), then apply, dry, and compress the intermediate layer, and then form the inner layer (3b).

  In this way, a transparent conductive layer (3) composed of a compressed layer of two or more conductive fine particles is formed. The total thickness of the conductive fine particle compressed layer may be about 0.5 μm to 2.5 μm, preferably about 1.0 to 2.0 μm, although it depends on the application. In FIG. 1, the surface layer (3a) and the inner layer (3b) of the transparent conductive layer (3) are conceptually represented. In the vicinity of the interface between the two layers (3a) and (3b), it is considered that small-sized particles (2a) and large-sized particles (2b) are mixed to some extent.

  Next, an adhesive layer (5) made of an adhesive composition is formed on the transparent conductive layer (3).

  The adhesive composition contains a curable compound and has an affinity for both the conductive layer (3) of the conductive film and the surface of the substrate (6) to which the conductive layer (3) is to be transferred. There are no particular limitations as long as the adhesive can strongly bond both, and various known adhesives can be used. Examples include acrylic adhesives, epoxy adhesives, isocyanate adhesives, silicone adhesives, and the like. Since there are voids between the conductive fine particles in the compressed layer (3) of the obtained conductive fine particles, the adhesive composition is impregnated in the compressed layer (3).

  The adhesive composition preferably contains a curable compound having an active energy ray reactive group. For example, the adhesive composition includes a polymer resin (P) and a curable compound (C) having the active energy ray reactive group (for example, an acrylic monomer (M)). As the active energy ray, ultraviolet rays, electron beams, γ rays, X-rays and the like can be used. When ultraviolet rays are used, the adhesive composition further contains a photopolymerization initiator.

  By adjusting the viscosity by using the polymer resin (P) component and the curable compound (C) (for example, acrylic monomer (M)) in combination, it has adhesiveness and is irradiated with active energy rays such as ultraviolet rays. An adhesive layer that becomes a cured product can be easily formed. What is necessary is just to have moderate adhesiveness.

  Examples of the polymer resin (P) include acrylic resins, silicone resins, epoxy resins, urethane resins, and cellulose resins. A publicly known thing can be used as acrylic resin, for example, acrylic resin 103B, 1BR-305 (all are the Taisei Kako Co., Ltd. product) etc. are mentioned.

  The said curable compound (C) is a compound which has active energy ray reactive groups, such as a (meth) acryloyl group and a vinyl group. In order to obtain sufficient hardness of the adhesive component after curing, the curable compound contains a polyfunctional monomer or oligomer containing two or more, preferably three or more active energy ray reactive groups in one molecule. It is preferable that

  The curable compound (C) preferably contains an acrylic monomer (M). Specific examples of the acrylic monomer (M) include 1,6-hexanediol di (meth) acrylate, triethylene glycol di (meth) acrylate, ethylene oxide-modified bisphenol A di (meth) acrylate, trimethylolpropane tri (Meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol tri (meth) acrylate, 3- (meth) acryloyloxyglycerin mono (meth) ) Acrylate and the like, but not necessarily limited thereto. Moreover, urethane acrylate, epoxy acrylate, etc. are also mentioned.

  As the acrylic monomer (M), known ones can be used. For example, trifunctional or higher acrylics such as KAYARAD GPO-303, KAYARAD TMPTA, and KAYARAD THE-330 (all manufactured by Nippon Kayaku Co., Ltd.). Based monomers.

  Moreover, you may use the compound which has a vinyl group as said curable compound (C). Examples of the compound having a vinyl group include ethylene glycol divinyl ether, pentaerythritol divinyl ether, 1,6-hexanediol divinyl ether, trimethylolpropane divinyl ether, ethylene oxide-modified hydroquinone divinyl ether, ethylene oxide-modified bisphenol A divinyl ether, Examples include, but are not necessarily limited to, pentaerythritol trivinyl ether, dipentaerythritol hexavinyl ether, ditrimethylolpropane polyvinyl ether, and the like.

  In the adhesive composition, depending on the mixing ratio of the polymer resin (P) and the curable compound (C) (preferably acrylic monomer (M)), the viscosity, tackiness, and hardness after curing of the coating film are increased. Changes. When the amount of the polymer resin (P) increases, the viscosity of the adhesive composition increases. If the polymer resin (P) is in an appropriate ratio, good tackiness can be obtained, and the more curable compound (C) (preferably acrylic monomer (M)), the more hardened after curing. In consideration of these, the blending ratio of the polymer resin (P) and the curable compound (C) may be appropriately determined. When the acrylic monomer (M) is used as the curable compound (C) The polymer resin (P) and the acrylic monomer (M) are preferably contained in a weight ratio P / M = 0/100 to 80/20 as a non-volatile content, and P / M = 1/99 to 50 / 50 is more preferable, and P / M = 2/98 to 30/70 is more preferable.

  The adhesive composition usually further contains a photopolymerization initiator. Various photopolymerization initiators can be used, and examples thereof include KAYACURE DETX-S (manufactured by Nippon Kayaku Co., Ltd.). The amount of the photopolymerization initiator is about 0.01 to 20% by weight based on the total (P + C) weight of the acrylic resin (P) and the curable component (C) containing the acrylic monomer (M). That's fine. When the adhesive component is cured by irradiation with active energy rays such as ultraviolet rays, productivity when the transfer conductive film is adhered to the target substrate is increased. Moreover, you may use the well-known thing which added the photoinitiator to the acrylic monomer as a photoinitiator. As what added the photoinitiator to the acryl-type monomer, ultraviolet curable resin SD-318 (Dainippon Ink Chemical Co., Ltd. product), XNR5535 (Nagase Sangyo Co., Ltd. product), etc. are mentioned, for example.

  A release film may be provided on the adhesive layer (5) of the transfer conductive film of the present invention to protect the adhesive layer surface until use.

  The adhesive layer (5) can be formed by applying an adhesive composition solution onto the conductive layer (3) and drying. Application of the adhesive composition solution is not particularly limited, and can be performed by a known method. For example, the adhesive composition solution can be applied by the same application method as that described in application of the anchor layer. Dry after application. Alternatively, the adhesive composition solution is applied onto a separately prepared release support that has been subjected to a release treatment, and dried to form an adhesive layer, and this adhesive layer on the release support and the support (1) The adhesive layer (5) may be provided on the conductive layer (3) by laminating and adhering (adhering) so that the upper conductive layer (3) is in contact therewith. In this case, simultaneously with the formation of the adhesive layer (5), a peeling support is provided on the adhesive layer, and the adhesive layer surface is protected until use.

  A part of the adhesive composition solution is impregnated in the conductive layer (3). The thickness of the adhesive layer (5) depends on the tackiness of the adhesive, but may be about 1 μm to 10 μm before curing, preferably 2 μm to 10 μm, and more preferably 2 μm to 5 μm. When the thickness of the adhesive layer (5) is less than 1 μm, the adhesion to the base material (6) tends to be lowered when it is bonded to the target base material (6). On the other hand, when the thickness exceeds 10 μm, there is a tendency that the adhesive layer is insufficiently cured and warpage of the substrate (6) (transparent conductor) after curing is increased. The thickness of the adhesive layer (5) after curing is not different from the thickness of the adhesive layer (5) before curing.

  As described above, the conductive film for transfer of the present invention can be produced.

Next, the transparent conductor of the present invention will be described.
FIG. 2 is a cross-sectional view showing a layer configuration example of a transparent conductor. In FIG. 2, a transparent conductive layer (3) composed of a compressed layer of conductive fine particles is provided on the surface of a substrate (6) via an adhesive layer (5). The transparent conductive layer (3) has a surface layer (3a) located on the surface opposite to the substrate (6), and an inner surface in contact with the layer (3a) and in contact with the adhesive layer (5). It consists of a compressed layer of two conductive fine particles including the layer (3b).

  The substrate (6) is not particularly limited as long as it is composed of a resin material that is transparent to visible light. Usually, a flexible resin sheet or resin film is used. Further, the substrate (6) is preferably one that transmits active energy rays used when the adhesive layer is cured. Examples of such a substrate include polyester films such as polyethylene terephthalate (PET), polyolefin films such as polyethylene and polypropylene, polycarbonate films, acrylic films, norbornene films (Arton manufactured by JSR Corporation, manufactured by Nippon Zeon Co., Ltd.) Zeonore etc.), polyethersulfone (PES) and the like. In addition to these resin films, a glass plate can also be used as a substrate. As a base material, what consists only of resin is preferable. When a flexible resin film is used, the transparent conductor is excellent in transparency, flexibility, and weight reduction as compared with the case where the substrate is a glass plate. Therefore, a flexible resin film is particularly effective when a transparent conductor is used for a touch panel, for example.

  In order to obtain the transparent conductor of the present invention, first, the conductive layer (3) of the above-mentioned transfer conductive film is transferred from the support (1) onto the target substrate (6). That is, the conductive film is attached to the surface of the target substrate (6) via the adhesive layer (5) of the conductive film so that the support (1) is on the outside, and after bonding, the adhesive layer ( 5) is cured by active energy ray irradiation (preferably ultraviolet irradiation), and then the support (1) of the conductive film is peeled off. Further, an adhesive similar to the adhesive component of the adhesive layer (5) may be applied to the surface of the target substrate (6) in advance.

  Since the adhesive component impregnated in the conductive layer (3) is cured simultaneously with the curing of the adhesive layer (5) by active energy ray irradiation, the cured adhesive layer (5) and the conductive layer (3 ) Will be even stronger. The adhesion between the surface layer (3a) and the inner layer (3b) is very high. Even when an intermediate layer exists between the surface layer (3a) and the inner layer (3b), the adhesion between these layers is also very high. Therefore, when the support (1) of the conductive film after the adhesive layer (5) is cured is peeled, peeling occurs between the support anchor layer (1b) and the conductive layer (3). The surface of the transparent conductive layer (3) is exposed.

  When transferring the conductive layer, the target substrate may be surface-treated in advance. For example, when the transfer target substrate is glass, the surface thereof may be surface treated with a silane coupling agent or the like.

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

[Example 1]
As shown in FIG. 1, a support (1) having an anchor resin layer (1b) formed on a support body (1a), a transparent conductive layer (3) [surface layer (3a) and inner layer (3b)] And the electroconductive film for transfer which has a photocurable adhesive bond layer (5) in this order was produced in the following procedure.

(Preparation of anti-transfer film used during compression)
One side of a 50 μm thick PET film (T100-50, manufactured by Mitsubishi Chemical Polyester Film) was subjected to corona treatment. A silicone hard coat liquid KP-854 (manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to the corona-treated surface of the PET film, dried, and cured at 70 ° C. for 48 hours to form a 0.4 μm thick silicone hard coat. In this way, an anti-transfer film during compression was prepared in advance.

(Formation of anchor resin layer)
Silicone resin was used for the hard anchor resin layer. 100 parts by weight of liquid A and 300 parts by weight of liquid B of silicone resin solution Fresella N-180 (manufactured by Panasonic Electric Works Co., Ltd.) were mixed to obtain a coating liquid for the anchor resin layer. One side of a 50 μm thick polyethylene terephthalate (PET) film (1a) (manufactured by Toray Industries, Inc.) was subjected to corona treatment. The coating solution was applied to the corona-treated surface of the PET film (1a), dried, and cured at 70 ° C. for 24 hours to form a 0.7 μm-thick silicone resin layer (1b).

(Formation of surface conductive layer)
300 parts by weight of ethanol was added to 100 parts by weight of ITO fine particles (BET: 63 m ² / g) having an average particle diameter of 10 nm, and the media was dispersed as zirconia beads with a disperser. The obtained coating liquid (IT powder solid content concentration 25 wt%) was applied onto the anchor resin layer (1b) using a bar coater, and dried by sending hot air of 50 ° C. The obtained film is called an ITO film before compression.

First, a preliminary experiment for confirming the compression pressure was performed.
Using a roll press machine equipped with a pair of metal rolls having a diameter of 140 mm (the roll surface is subjected to hard chrome plating), the roll is not rotated and the roll is heated to room temperature (23 ° C.) without heating. The ITO film before compression was sandwiched and compressed. At this time, in order to prevent the ITO particles of the ITO-containing coating film from being transferred to the roll side between the ITO-containing coating film surface and the roll surface of the pre-compression ITO film, the transfer prevention film is transferred. The hard coat surface of the prevention film and the ITO-containing coating film surface were overlapped so as to contact each other. At this time, the pressure per unit length in the film width direction was 660 N / mm. Next, when the pressure was released and the length of the compressed portion in the longitudinal direction of the film was examined, it was 1.9 mm. From this result, it was compressed at a pressure of 347 N / mm ² per unit area.

  Next, the ITO film before compression similar to that used in the preliminary experiment was sandwiched between metal rolls and compressed at a pressure of 660 N / mm, and the roll was rotated and compressed at a feed rate of 5 m / min. In this way, a compressed ITO surface layer (3a) was formed on the hard anchor resin layer (1b). The thickness of the ITO surface layer (3a) was 0.5 μm.

(Formation of internal conductive layer)
300 parts by weight of ethanol was added to 100 parts by weight of ITO fine particles (BET: 30 m ² / g) having an average particle diameter of 25 nm, and the media was dispersed as zirconia beads with a disperser. The obtained coating solution (solid content concentration of ITO powder 25% by weight) was applied onto the ITO surface layer (3a) using a bar coater, and dried by sending hot air of 50 ° C.

  Next, by the same operation as the compression of the surface conductive layer, the ITO film was sandwiched between metal rolls and compressed at a pressure of 660 N / mm, and the roll was rotated and compressed at a feed rate of 5 m / min. In this way, a compressed ITO inner layer (3b) was formed on the ITO surface layer (3a). The thickness of the ITO inner layer (3b) was 0.5 μm.

(Formation of photocurable adhesive layer)
Next, the photocurable acrylic resin composition solution was applied by a bar coating method. Here, the solution of the acrylic resin composition is 30 parts by mass of acrylic polymer 1BR-305 (solid content: 39.5% by weight, manufactured by Taisei Kako Co., Ltd.) and ultraviolet curable resin liquid XNR5535 (manufactured by Nagase Sangyo Co., Ltd.). 50 parts by mass, 20 parts by mass of dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.), 3 parts by mass of photopolymerization initiator: Irgacure 184 (manufactured by Ciba Specialty Chemicals), and methyl ethyl ketone (MEK) It was prepared by mixing 150 parts by mass.

  After application of the acrylic resin composition solution, MEK was volatilized to form an adhesive layer (5) having a thickness of 3 μm. Thereafter, a release PET film A314 (manufactured by Teijin Limited) was laminated on the adhesive layer (5) to obtain a conductive film for transfer (10).

(Applying transparent conductive layer to substrate by transfer)
The peeled PET film of the obtained conductive film for transfer is peeled off to expose the adhesive layer (5), and the adhesive layer (5) is 100 μm thick PET film substrate U34 (manufactured by Toray Industries, Inc.) (6) It was pasted together with a laminator so that it touched. Then, the acrylic resin composition is cured by irradiating the adhesive layer (5) through the PET film substrate (6) with ultraviolet rays having an integrated illuminance of 400 mJ / cm ^{2 using} a metal halide lamp as a light source. Layer (5) was obtained. Thereafter, the support PET film (1) was peeled off. The adhesion between the silicone resin layer (1b) and the support body (1a) is higher than the adhesion between the silicone resin layer (1b) and the ITO compression layer (3), and the silicone resin layer (1b) is the support body. It was peeled off with (1a). An exposed ITO compressed layer (3) was formed on the PET film substrate (6). As shown in FIG. 2, an ITO compressed layer (3) [surface layer (3a) and inner layer (3b)] was applied to the PET film substrate (6) through a cured adhesive layer (5). In this way, a transparent conductor (20) having an ITO transparent conductive layer was obtained.

(Production of touch panel)
A touch panel was prepared by using a transparent conductor (20) having an ITO transparent conductive layer as an upper electrode and glass ITO printed with a dot spacer as a lower electrode, facing each other.

[Examples 2 to 21]
Example 1 except that the average particle diameter and film thickness of the ITO fine particles of the surface layer (3a) and the average particle diameter and film thickness of the ITO fine particles of the inner layer (3b) were changed as shown in Table 1, respectively. Thus, a conductive film for transfer was obtained. Using the obtained transfer conductive film, the transparent conductive layer was transferred to a PET film substrate in the same manner as in Example 1 to obtain a transparent conductor. And the touch panel was produced.

[Examples 22 to 23]
The average particle diameter and film thickness of the ITO fine particles of the surface layer (3a) and the average particle diameter and film thickness of the ITO fine particles of the inner layer (3b) were changed as shown in Table 2, respectively, and the surface layer (3a) and A conductive film for transfer was obtained in the same manner as in Example 1 except that an intermediate conductive layer was formed between the inner layer (3b). Using the obtained transfer conductive film, the transparent conductive layer was transferred to a PET film substrate in the same manner as in Example 1 to obtain a transparent conductor. And the touch panel was produced.

[Comparative Examples 1-8]
Example 1 except that the average particle diameter and film thickness of the ITO fine particles of the surface layer (3a) and the average particle diameter and film thickness of the ITO fine particles of the inner layer (3b) were changed as shown in Table 3, respectively. Thus, a conductive film for transfer was obtained. Using the obtained transfer conductive film, the transparent conductive layer was transferred to a PET film substrate in the same manner as in Example 1 to obtain a transparent conductor. And the touch panel was produced. In Comparative Example 6, the conductive layer was a single layer (average particle diameter of ITO fine particles 25 μm, film thickness 1.0 μm).

[Performance evaluation]
Each transparent conductor was evaluated as follows.

(Surface electrical resistance)
Using the resistance measuring device (Loresta EP, manufactured by Mitsubishi Chemical Corporation), the electrical resistance value (Ω / □) of the surface of each of the transparent conductors at the initial stage and those after the sliding test shown below is 4 It was measured by the terminal method.

(Sliding test)
Four double-sided pressure-sensitive adhesive tapes having a size of 5 mm × 45 mm and a thickness of 100 μm were attached to the surface of the transparent conductive layer of the obtained transparent conductor so that a square frame of 50 mm × 50 mm was formed. A 50 mm × 50 mm glass plate was bonded to the double-sided pressure-sensitive adhesive tape while being aligned with the frame of the attached double-sided pressure-sensitive adhesive tape. In this way, a test touch panel was obtained in which the transparent conductive layer of the transparent conductor and the glass plate were arranged to face each other using the double-sided adhesive tape as a spacer.
The surface of the prepared touch panel on the PET film substrate side is slid by reciprocating the pen tip while being pressed against the glass plate with a polyacetal touch pen having a tip with a radius of curvature of 0.8 mm. A dynamic test was performed. In the sliding test, a load of 250 g was applied to the touch pen, the same part was slid, the moving distance was 30 mm, and the number of reciprocating movements was 200,000 times.

(Resistance change rate)
For each transparent conductor, the rate of change in resistance was obtained from the following equation from the initial surface resistance value Ri (before the sliding test) and the surface electric resistance value Rt after the sliding test. The smaller the resistance change rate, the better the durability.
Resistance change rate = Rt / Ri

  The obtained results are shown in Tables 1-3.

  From Tables 1 to 3, in each Example, the initial electrical resistance value was low, the resistance change after the sliding test was small, and the durability was excellent.

Claims (8)

A transparent conductor having a substrate, an adhesive layer on the substrate, and a transparent conductive layer on the adhesive layer,
The adhesive layer is a cured product layer of an adhesive composition containing at least a curable compound,
The conductive layer comprises a compressed layer of at least two conductive fine particles including a surface layer located on the surface opposite to the substrate and an inner layer in contact with the adhesive layer,
The compressed layer of at least two layers of conductive fine particles is composed of conductive fine particles having different average particle diameters, respectively.
The said surface layer is a transparent conductor comprised from the conductive fine particle which has the smallest average particle diameter among the compression layers of the said at least 2 layer of conductive fine particle.   The transparent conductor according to claim 1, wherein an average particle diameter of the conductive fine particles constituting the surface layer is 10 to 20 nm.   The transparent conductor according to claim 1, wherein the surface layer has a thickness of 0.2 to 0.7 μm.   The transparent conductor in any one of Claims 1-3 whose average particle diameter of the electroconductive fine particles which comprise the said inner layer is 25-80 nm.   The transparent conductor according to claim 1, wherein the inner layer has a thickness of 0.3 to 1.3 μm.   The conductive fine particles include indium oxide, tin-doped indium oxide (ITO), gallium-doped indium oxide, zinc-doped indium oxide, tin oxide, antimony-doped tin oxide (ATO), fluorine-doped tin oxide (FTO), zinc oxide, and aluminum. Conductive inorganic fine particles selected from the group consisting of doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), fluorine-doped zinc oxide, indium-doped zinc oxide, boron-doped zinc oxide, and cadmium oxide. The transparent conductor according to any one of 5. A conductive film for transfer comprising at least a support, a transparent conductive layer peelable from the support on the support, and an adhesive layer on the transparent conductive layer;
The adhesive layer is made of an adhesive composition containing at least a curable compound,
The conductive layer comprises a compressed layer of at least two conductive fine particles including a layer in contact with the support and a layer in contact with the adhesive layer,
The compressed layer of at least two layers of conductive fine particles is composed of conductive fine particles having different average particle diameters, respectively.
The conductive film for transfer, wherein the layer in contact with the support is composed of conductive fine particles having the smallest average particle diameter among the compressed layers of the at least two conductive fine particles. A method for producing the transparent conductor according to claim 1, comprising:
The conductive film for transfer according to claim 7 is attached to the surface of the base material with the support on the outside through the adhesive layer of the film, and the adhesive layer is cured after the application. And then peeling the support. A method for producing a transparent conductor.

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