JP6074851B2 - Conductive optical member - Google Patents

Description

  The present invention relates to a conductive optical member having both transparency and conductivity.

  Conventionally, conductive optical members having both transparency and conductivity have been widely applied to devices such as touch panels, organic EL, liquid crystal displays, and solar cells.

  In recent years, a conductive optical member including a conductive layer containing metal nanowires such as silver nanowires has been proposed. In this case, in the conductive layer, light scattering due to the metal nanowires is likely to occur. Therefore, a phenomenon that the conductive layer appears to be whitish is likely to occur in a touch panel, a display, or the like. This phenomenon is also called black float because the color that should be black appears to be bright thereby, but in this specification is called a milky face.

  Therefore, Patent Document 1 proposes preventing irregular reflection of light on the metal nanowires by adsorbing a colored compound to the metal nanowires in the conductive layer (transparent conductive film).

Japanese Patent No. 4893867

  However, when a colored compound is adsorbed on the metal nanowire as disclosed in Patent Document 1, the conductivity of the metal nanowire is impaired by the colored compound. That is, when the appearance is improved by preventing the milky face, a situation occurs in which the conductivity, which is an essential function of conductivity, is impaired.

  Moreover, when light passes through the conductive layer containing metal nanowires, the hue of the light after transmission becomes more yellow or red than before transmission. Therefore, in order to improve the appearance of the conductive optical member, it is necessary to suppress the milky face and at the same time suppress the change in the hue of light before and after passing through the conductive optical member.

  The present invention has been made in view of the above reasons, and can suppress the milky face caused by the metal nanowire without impeding the conductivity of the conductive layer containing the metal nanowire, and the hue of transmitted light. It is an object of the present invention to provide a conductive optical member that can suppress the change of the above.

The conductive optical member according to the first aspect of the present invention includes a base material having light permeability and a conductive layer, and the conductive layer is on the first surface and the side opposite to the first surface. A conductive optical member having a second surface positioned, wherein the substrate is positioned on the second surface side with respect to the conductive layer,
The conductive layer contains metal nanowires and a blue compound, and the blue compound is unevenly distributed on the first surface side in the conductive layer,
The conductive optical member further includes an adjustment layer positioned on the second surface side with respect to the conductive layer, and the adjustment layer contains a yellow compound.

  In the conductive optical member according to the second aspect of the present invention, in the first aspect, the conductive layer is located on a side opposite to the adjustment layer with respect to the first layer and the first layer. A second layer, wherein the metal nanowires are dispersed in the first layer, and the blue compound is dispersed in the second layer.

  In the electroconductive optical member which concerns on the 3rd aspect of this invention, in the 1st or 2nd aspect, the said metal nanowire contains silver nanowire.

  In the conductive optical member according to the fourth aspect of the present invention, in any one of the first to third aspects, the adjustment layer is interposed between the base material and the conductive layer.

  According to the present invention, the adjustment layer can suppress the milky face caused by the metal nanowires. Further, the blue compound and the adjustment layer in the conductive layer can suppress a change in the hue of the light before and after transmission when the light is transmitted through the conductive optical member. Moreover, since the blue compound is dispersed in the conductive layer, the blue compound is unlikely to hinder the conductivity of the conductive layer. Accordingly, the appearance of the conductive optical member is improved without impeding the conductivity of the conductive layer.

It is a schematic sectional drawing which shows the electroconductive optical member in one Embodiment of this invention. It is a graph which shows the wavelength dependence of the light reflectivity of silver nanowire.

  As shown in FIG. 1, the conductive optical member 1 according to the present embodiment includes a base material 2 having optical transparency and a conductive layer 3. The conductive layer 3 has a first surface 33 and a second surface 34 located on the opposite side of the first surface 33. The substrate 2 is located on the second surface 34 side with respect to the conductive layer 3.

  The conductive layer 3 contains the metal nanowire 4 and a blue compound. The blue compound is unevenly distributed near the first surface 33 in the conductive layer 3.

  The conductive optical member 1 further includes an adjustment layer 5 positioned on the second surface 34 side with respect to the conductive layer 3, and the adjustment layer 5 contains a yellow compound.

  According to this embodiment, even if light passes through the conductive optical member 1, a milky face is less likely to occur. In addition, the hue of light hardly changes between before and after passing through the conductive optical member 1. For this reason, the external appearance of the conductive optical member 1 is improved. This action is considered to be achieved by the following mechanism.

  FIG. 2 shows the wavelength dependence of the light reflectance of silver nanowires. As shown in FIG. 2, the light reflectance of the metal nanowire 4 has a peak in the short wavelength region (blue region), and the light reflectance is low in the long wavelength region. For this reason, when the ratio of the component of the short wavelength area | region in the light irradiated to the metal nanowire 4 is high, the milky face resulting from the metal nanowire 4 becomes remarkable.

  However, in this embodiment, when light passes through the conductive optical member 1 from the base material 2 side to the conductive layer 3 side, first, in the adjustment layer 5, the yellow compound is a component in the short wavelength region of light. Absorb selectively. For this reason, when the light reaches the conductive layer 3, the proportion of the short wavelength region component in the light decreases. As a result, the milky face due to the reflection of the component in the short wavelength region by the metal nanowire 4 is suppressed.

  Furthermore, when light passes through the conductive layer 3, the blue compound absorbs components in the long wavelength region in the light, so that the proportion of components in the long wavelength region in the light is low. In this way, first, the adjustment layer 5 absorbs the short wavelength component in the light, and then the conductive layer 3 absorbs the component in the long wavelength region in the light. The ratio of the short wavelength component in the light and the ratio of the component in the long wavelength region hardly change between before and after transmission. For this reason, the hue of light becomes difficult to change.

  Moreover, in this embodiment, when light is irradiated to the conductive optical member 1 from the conductive layer 3 side and this light is reflected by the conductive optical member 1, the component in the short wavelength region of the light is a blue compound. It becomes easy to be reflected, and for this reason, the component of a short wavelength area | region becomes difficult to reach | attain the metal nanowire 4. FIG. For this reason, reflection of light by the metal nanowire 4 is suppressed. Even if light is reflected by the metal nanowire 4, the reflected light toward the adjustment layer 5 is easily absorbed by the yellow compound in the adjustment layer 5. For this reason, the light reflected by the metal nanowire 4 and emitted to the outside of the conductive optical member 1 is reduced, thereby suppressing the milky face.

  In the present embodiment, since the blue compound is dispersed in the conductive layer 3, the blue compound is unlikely to hinder the conductivity of the metal nanowire 4. For this reason, high conductivity of the conductive layer 3 is easily maintained.

  In the present embodiment, the conductive layer 3 includes a first layer 31 and a second layer 32 located on the opposite side of the adjustment layer 5 with respect to the first layer 31, and the metal nanowire 4 is the first layer 31. The blue compound is dispersed in the second layer 32 while being dispersed in the layer 31. Thereby, the blue compound is unevenly distributed near the first surface 33 in the conductive layer 3 and dispersed.

  Therefore, according to the present embodiment, when light passes through the conductive layer 3, the light first passes through the first layer 31 containing the metal nanowire 4, and then the second layer containing the blue compound. 32 is transmitted. For this reason, the light before the long wavelength component is absorbed by the blue compound (that is, the light in a state where the ratio of the short wavelength component is low) is easily irradiated to the metal nanowire 4. As a result, the reflection of light by the metal nanowire 4 is particularly suppressed, and the milky face is more reliably suppressed.

  In the present embodiment, the second layer 33 is directly laminated on the first layer 31, but another layer may be interposed between the first layer 31 and the second layer 33.

  In addition, if the blue compound is unevenly distributed near the first surface 33 in the conductive layer 3, the conductive layer 3 includes the first layer 31 and the second layer 32 as in the present embodiment. May not be provided. For example, the conductive layer 3 is composed of a single layer, and the metal nanowires 4 and the blue compound are mixed in the conductive layer 3, and further the concentration in the conductive layer 3 is increased toward the first surface 33 side. A blue compound concentration gradient may be formed.

  In this embodiment, it is preferable that the metal nanowire 4 contains a silver nanowire.

  In the present embodiment, the adjustment layer 5 is interposed between the base material 2 and the conductive layer 3. Thereby, the adjustment layer 5 is arranged at a position on the second surface 34 side with respect to the conductive layer 3.

  For this reason, according to this embodiment, the adjustment layer 5 can also suppress precipitation of low molecular weight components such as oligomers from the surface of the substrate 2 on the conductive layer 3 side. For this reason, the external appearance of the conductive optical member 1 is further improved.

  In the present embodiment, the adjustment layer 5 is directly laminated on the conductive layer 3, but another layer may be interposed between the conductive layer 3 and the adjustment layer 5. In the present embodiment, the base material 2 is directly laminated on the adjustment layer 5, but another layer may be interposed between the adjustment layer 5 and the base material 2.

  In addition, when the adjustment layer 5 is disposed at the position on the second surface 34 side with respect to the conductive layer 3, the base material 2 may be interposed between the adjustment layer 5 and the conductive layer 3. That is, for example, the base material 2 may be laminated on the second surface 34 of the conductive layer 3, and the adjustment layer 5 may be laminated on the opposite side of the base material 2 from the conductive layer 3.

  The yellow compound preferably contains a compound having an S atom. That is, it is preferable that at least a part of the yellow compound includes an S atom. In this case, the compound having S atoms suppresses sulfidation of the metal nanowire 4. For this reason, deterioration of the metal nanowire 4 is suppressed, and the conductivity of the conductive layer 3 is easily kept high.

  In the present embodiment, a conductor having an appropriate pattern shape may be formed by performing an etching process or the like on the conductive layer 3. In the etching process, the conductive layer 3 may be partially removed by a dry etching process or the like, so that a conductor composed of the remaining part of the conductive layer 3 may be formed. By conducting a wet etching process or the like on the conductive layer 3, the metal nanowire 4 is partially removed from the conductive layer 3, thereby forming a conductor including a region where the metal nanowire 4 in the conductive layer 3 remains. May be.

  This embodiment will be described in further detail.

  In this embodiment, the 2nd layer 32, the 1st layer 31, the adjustment layer 5, and the base material 2 are laminated | stacked in this order.

  First, the substrate 2 will be described. The substrate 2 is light transmissive. The light transmittance of the substrate 2 is preferably 50% or more, more preferably 70% or more, and particularly preferably 80% or more. The haze of the substrate 2 is preferably 3% or less. In this case, the visibility of images and the like through the conductive optical member 1 is improved, and it is particularly suitable as a member for optical applications. More preferably, the haze is 1.5% or less.

  Although the shape in particular of the base material 2 is not restrict | limited, It is preferable that it is plate shape or a film form. In particular, in order to improve the productivity and transportability of the conductive optical member 1, the shape of the base material 2 is preferably a film. When the substrate 2 is in the form of a film, the thickness of the substrate 2 is preferably in the range of 10 μm to 500 μm, and more preferably in the range of 25 μm to 150 μm.

  The material of the base material 2 is not particularly limited. Examples of the material of the substrate 2 include glass and transparent resin. Examples of transparent resins include polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polymethyl methacrylate copolymer, triacetyl cellulose, polyolefin, polyamide, polyvinyl chloride, amorphous polyolefin, cycloolefin polymer, cycloolefin copolymer, etc. Can be mentioned.

  In particular, the substrate 2 is preferably formed from polyester. Among the polyester films, in particular, biaxially stretched films made of polyethylene terephthalate (PET) or polyethylene naphthalate have excellent mechanical properties, heat resistance, chemical resistance, etc., so magnetic tape, ferromagnetic thin film tape, packaging Films for electronic use, films for electronic parts, electrical insulating films, films for laminating, films to be attached to the surface of displays, and films for protecting various members. Especially for display applications, base films such as prism lens sheets, touch panels, and backlights, which are members of liquid crystal display devices, TV optical film base films, optical films used for plasma TV front optical filters, and near infrared rays It is suitable as a cut film, a base film of an electromagnetic shielding film, and the like.

  Examples of polyesters include aromatic dicarboxylic acid components such as terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 4,4′-diphenyldicarboxylic acid, ethylene glycol, 1,4-butanediol, 1,4- Aromatic polyesters produced by reaction with glycol components such as cyclohexanedimethanol and 1,6-hexanediol are preferred. In particular, polyethylene terephthalate, polyethylene-2,6-naphthalene dicarboxylate and the like are preferable. In addition, the polyester may be produced by copolymerizing a plurality of the exemplified components.

  The base material 2 may contain organic or inorganic particles. In this case, the winding property and transportability of the base material 2 are improved. The particles that can be contained in the substrate 2 include calcium carbonate particles, calcium oxide particles, aluminum oxide particles, kaolin, silicon oxide particles, zinc oxide particles, crosslinked acrylic resin particles, crosslinked polystyrene resin particles, urea resin particles, and melamine resin. Examples thereof include particles and crosslinked silicone resin particles.

  The substrate 2 may further contain a colorant, an antistatic agent, an ultraviolet absorber, an antioxidant, a lubricant, a catalyst, other resins, and the like as long as the transparency is not impaired.

  The surface of the substrate 2 on the conductive layer 3 side is preferably subjected to surface treatment before the adjustment layer 5 is formed on this surface. In this case, the wettability and adhesion between the substrate 2 and the adjustment layer 5 can be improved. Even when the adjustment layer 5 is not interposed between the base material 2 and the conductive layer 3 and the base material 2 and the conductive layer 3 are in direct contact, the surface of the base material 2 on the conductive layer 3 side is It is preferable that the treatment is performed. In this case, the wettability and adhesion between the base material 2 and the conductive layer 3 can be improved. Examples of the surface treatment method include physical surface treatment such as plasma treatment, corona discharge treatment and flame treatment, and chemical surface treatment with a coupling agent, an acidic component, an alkaline component, and the like.

  In this embodiment, the back surface coating layer 6 is laminated on the base material 2 on the side opposite to the conductive layer 3. It is preferable that the surface of the substrate 2 that is located on the side opposite to the conductive layer 3 is subjected to a surface treatment before the back surface coating layer 6 is formed on this surface. In this case, it is possible to improve wettability, adhesion and the like between the substrate 2 and the back surface coating layer 6. Examples of the surface treatment method include physical surface treatment such as plasma treatment, corona discharge treatment and flame treatment, and chemical surface treatment with a coupling agent, an acidic component, an alkaline component, and the like.

  Next, the back surface coating layer 6 will be described. The back surface coating layer 6 suppresses the precipitation of low molecular weight components such as oligomers from the surface of the substrate 2 located on the side opposite to the conductive layer 3. For this reason, whitening of the base material 2 is suppressed, and good transparency of the conductive optical member 1 is maintained. Further, the whitening of the base material 2 due to the low molecular weight component causes the same appearance defect as the milky face due to the metal nanowires. However, in this embodiment, since the whitening of the base material 2 is suppressed, In combination, the appearance of the conductive optical member 1 is further improved.

  Although the material in particular of the back surface coating layer 6 is not restrict | limited, For example, it forms from acrylate resin, urethane acrylate resin, etc.

  In order for the back surface coating layer 6 to sufficiently suppress the precipitation of low molecular weight components from the base material 2, the thickness of the back surface coating layer 6 is preferably in the range of 0.5 μm to 10 μm.

  The back surface coating layer 6 preferably has anti-blocking properties. That is, it is preferable that blocking is suppressed by the back surface coating layer 6 when the conductive optical member 1 is rolled up and stacked. For that purpose, it is preferable that the surface of the back surface coating layer 6 is formed uneven. For that purpose, it is preferable that the surface of the back surface coating layer 6 is subjected to mechanical processing so that the surface is formed to be uneven. It is also preferable that the back surface coating layer 6 contains a filler such as silica particles so that irregularities are formed on the surface of the back surface coating layer 6. In this case, the back surface coating layer 6 contains, for example, acrylate resin or urethane acrylate resin in the range of 80% by mass to 95% by mass, and further silica particles having an average particle diameter of 250 nm of 5% by mass to 20% by mass. It is preferable to contain within the range.

  It is also preferable that the back surface coating layer 6 improves the lubricity of the conductive optical member 1, and for this purpose, it is also preferable that the back surface coating layer 6 contains, for example, a silicone leveling agent.

  Next, the adjustment layer 5 will be described. The adjustment layer 5 contains a yellow compound as described above.

  The yellow compound is not particularly limited as long as the yellow compound sufficiently absorbs components in the short wavelength region in the light. In order to sufficiently reduce the proportion of components in the short wavelength region in the light, it is particularly preferable that the yellow compound has a maximum wavelength of light absorption in the wavelength region of 380 to 500 nm.

  The yellow compound may contain either a dye or a pigment. Examples of the dye include anthraquinone quinone dye, azo dye, hydrazolone dye, quinoxaline dye, azomethine dye, quinophthalone dye, isoindoline dye, and the like. Specific examples of dyes include trade name Kayaset Yellow SF-G, trade name Kayaset Yellow 2G, trade name Kayaset Yellow GN, trade name Kayaset Yellow AG, trade name Kayaset Yellow AH, trade name Kayaset Yellow manufactured by Nippon Kayaku Co., Ltd. E-L2R and trade name Kayaset Yellow E-3RLR. Examples of pigments include yellow iron oxide (yellow iron), opium (sulfide), cadmium yellow, cobalt yellow, lead monoxide, lead tin yellow, lead antimony, chromic yellow, yellow lead, strontium yellow, and zinc yellow. Can be mentioned.

  The adjustment layer 5 may further contain a red compound. The red compound may also contain any of a dye and a pigment. Examples of the dye include anthraquinone dyes, azo dyes, and quinacridone dyes. Specific examples of dyes include trade name Kayaset Yellow SF-G, trade name Kayaset Red AG, trade name Kayaset Red A-2G, trade name Kayaset Red A-BR, trade name Kayaset Red E-, manufactured by Nippon Kayaku Co., Ltd. CG, trade name Kayaset Red E-BG, trade name Kayaset Red E-GRN, trade name Kayaset Red G, trade name Kayaset Red B, trade name Kayaset Red SF-B, and the like. Examples of the pigment include red iron oxide (Bengara).

  If the yellow compound contains a compound having S atoms, as described above, this compound exerts an action of suppressing sulfidation of the metal nanowire 4, thereby suppressing deterioration of the metal nanowire 4, and High conductivity is easily maintained. The compound having an S atom is selected from, for example, a thiol-based sulfur-based antioxidant and a sulfur-based antioxidant having a sulfide group. When the adjustment layer 5 contains a sulfur-based antioxidant, it is also preferable that the adjustment layer 5 further contains a phenol-based antioxidant. In this case, the corrosion of the metal nanowire 4 is further suppressed. When a yellow compound contains the compound provided with S atom, it is preferable that the ratio of the compound provided with S atom with respect to the whole yellow compound exists in the range of 20-100 mass%.

  The amount of the yellow compound in the adjustment layer 5 can be adjusted as appropriate so that the ratio of components in the short wavelength region in the light is sufficiently reduced when light passes through the adjustment layer 5. In particular, in order to ensure good light transmittance of the conductive optical member 1 and to effectively suppress the change in the hue of light before and after passing through the conductive optical member 1, the metal in the conductive layer 2 is used. The ratio of the yellow compound in the adjustment layer 5 to the nanowire 4 is preferably in the range of 25 to 50% by mass.

  When the adjustment layer 5 is interposed between the base material 2 and the conductive layer 3 as in this embodiment, the adjustment layer 5 causes precipitation of low molecular weight components such as oligomers from the surface of the base material 2 on the conductive layer 3 side. It can also be suppressed. For this reason, whitening of the base material 2 is suppressed, and good transparency of the conductive optical member 1 is maintained. Further, the whitening of the base material 2 due to the low molecular weight component causes the same appearance defect as the milky face due to the metal nanowires. However, in this embodiment, since the whitening of the base material 2 is suppressed, In combination, the appearance of the conductive optical member 1 is further improved.

  The thickness of the adjustment layer 5 is preferably in the range of 30 to 10,000 nm. When this thickness is 30 nm or more, precipitation of low molecular weight components from the substrate 2 is sufficiently suppressed. When the thickness is 10000 nm or less, the amount of curing shrinkage of the adjustment layer 5 when the adjustment layer 5 is formed on the substrate 2 is reduced, so that the substrate 2 is less likely to warp. In particular, when the substrate 2 is in the form of a film, the warp of the substrate 2 is remarkably suppressed.

  The adjustment layer 5 is formed from an appropriate resin composition (first composition) containing, for example, a yellow compound and a resin component. The first composition is preferably a reactive curable resin composition, for example, preferably at least one of a thermosetting resin composition and an ionizing radiation curable resin composition.

  When the first composition is a thermosetting resin composition, the resin component in the first composition is, for example, a phenol resin, urea resin, diallyl phthalate resin, melamine resin, unsaturated polyester resin, polyurethane resin, epoxy One or more thermosetting resins selected from resins, aminoalkyd resins, silicon resins, and polysiloxane resins are contained. A 1st composition may contain a crosslinking agent, a polymerization initiator, a hardening | curing agent, a hardening accelerator, a solvent etc. with a thermosetting resin as needed. In this case, the adjustment layer 5 can be formed by applying the first composition onto, for example, the substrate 2 and then heating and thermosetting the first composition.

  When the first composition is an ionizing radiation curable resin composition, the resin component in the first composition preferably includes, for example, a resin having an acrylate functional group. Examples of the resin having an acrylate functional group include oligomers such as (meth) acrylates of a relatively low molecular weight polyfunctional compound, prepolymers, and the like. Examples of the polyfunctional compound include polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and polyhydric alcohols. It is also preferred that the first composition further contains a reactive diluent. Examples of reactive diluents include monofunctional monomers such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone, trimethylolpropane tri (meth) acrylate, and hexanediol (meth) acrylate. , Tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di The polyfunctional monomer of (meth) acrylate is mentioned.

  When the first composition is a photocurable resin composition such as an ultraviolet curable resin composition, the first composition preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include acetophenones, benzophenones, α-amyloxime esters, thioxanthones, and the like. The first composition may contain a photosensitizer in addition to the photopolymerization initiator or in place of the photopolymerization initiator. Examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, and thioxanthone. The adjustment layer 5 can be formed by applying such a first composition onto, for example, the base material 2 and subsequently irradiating the first composition with light such as ultraviolet rays and photocuring.

The adjustment layer 5 may contain appropriate particles for the purpose of adjusting the film quality and adjusting the refractive index. Specific examples of the particles include particles containing one or more oxides selected from titanium, aluminum, cerium, yttrium, zirconium, niobium, and antimony. Specific examples of the oxide include ZnO (refractive index 1.90), TiO ₂ (refractive index 2.3 to 2.7), CeO ₂ (refractive index 1.95), Sb ₂ O ₅ (refractive index 1. 71), SnO _2, ITO (refractive index 1.95), Y ₂ O ₃ (refractive index 1.87), La ₂ O ₃ (refractive index 1.95), ZrO ₂ (refractive index 2.05), Al ₂ O ₃ (refractive index 1.63) and the like. The particle size of the particles is preferably in the range of 0.5 nm to 150 nm. This particle diameter is the diameter of a circle (area equivalent circle) having the same area as the projected area calculated from the electron micrograph image of the particle. Content of the particle | grains in the adjustment layer 5 exists in the range of 5-70 volume%, for example.

  The surface of the adjustment layer 5 on the conductive layer 3 side is preferably subjected to a surface treatment before the conductive layer 3 is formed on this surface. In this case, the wettability, adhesion, etc. between the adjustment layer 5 and the conductive layer 3 can be improved. Examples of the surface treatment method include plasma surface treatment, corona discharge treatment, physical surface treatment such as flame treatment, and chemical surface treatment with a coupling agent, acid, and alkali.

  Next, the conductive layer 3 will be described.

  The first layer 31 in the conductive layer 3 contains the metal nanowire 4. In the present embodiment, the first layer 31 does not contain a blue compound.

  The metal nanowire 4 is a metal fiber having a nano-sized diameter. The nano size refers to a size of 1000 nm or less, and may include a size of 1 nm or less.

  The type of metal constituting the metal nanowire 4 is not particularly limited, and examples thereof include Ag, Au, Cu, Co, Al, and Pt. In particular, in order to further improve the conductivity of the first layer 31, the metal constituting the metal nanowire 4 preferably includes at least one selected from Au, Ag, Cu, and Pt, and in particular, at least selected from Ag and Cu. It is preferable to include one kind.

  The method for producing the metal nanowire 4 is not particularly limited, and for example, a known method such as a liquid phase method or a gas phase method can be adopted. For example, as a specific example of a method for producing silver nanowires, Adv. Mater. 2002, 14, P833-837, Chem. Mater. Examples include methods disclosed in documents such as 2002, 14, P4736 to 4745, and Japanese translations of PCT publication No. 2009-505358. Specific examples of the method for producing gold nanowires include the method disclosed in JP-A-2006-233252. Examples of the method for producing the copper nanowire include a method disclosed in JP-A No. 2002-266007. Examples of the method for producing the cobalt nanowire include a method disclosed in Japanese Patent Application Laid-Open No. 2004-148771. In particular, Adv. Mater. 2002, 14, P 833-837, and Chem. Mater. If the manufacturing method of the silver nanowire currently disclosed by 2002, 14, P4736-4745 is employ | adopted, a silver nanowire can be manufactured simply and in large quantities by an aqueous system.

  The average diameter of the metal nanowire 4 is preferably in the range of 10 to 100 nm. When the average diameter is 10 nm or more, the conductivity of the first layer 31 is particularly high. When the average particle size is 100 nm or less, the transparency of the first layer 31 is particularly high. The average diameter of the metal nanowire 4 is more preferably in the range of 20 to 100 nm, and still more preferably in the range of 40 to 100 nm.

  The average length of the metal nanowire 4 is preferably in the range of 1 to 100 μm. When the average length is 1 μm or more, the conductivity of the first layer 31 is particularly high. In addition, when the average particle diameter is 100 μm or less, the metal nanowires 4 are less likely to aggregate in the first layer 31, and thus the transparency of the first layer 31 is improved. The average length of the metal nanowire 4 is more preferably in the range of 1 to 50 μm, and most preferably in the range of 3 to 50 μm.

  The average diameter of the metal nanowires 4 is a value obtained by measuring the diameters of a sufficient number of metal nanowires 4 and arithmetically averaging the results. The average length of the metal nanowires 4 is a value obtained by measuring the length of a sufficient number of metal nanowires 4 and arithmetically averaging the results. The diameter and length of the metal nanowire 4 are derived by image analysis of an electron microscope image of the metal nanowire 4. For example, when the electron microscope image of the metal nanowire 4 is bent, the diameter (projection diameter (D)) and area (projection area (S)) of the metal nanowire 4 are calculated by image analysis. Further, the length (L = S / D) of the metal nanowire 4 is obtained by dividing the projected area (S) by the projected diameter (D). In order to derive the average diameter and the average length of the metal nanowires 4, it is preferable to measure the diameters and lengths of at least 100 metal nanowires 4. More preferably, it is measured.

  The ratio of the metal nanowire 4 in the first layer 31 is not particularly limited, but is preferably in the range of 0.01% by mass to 90% by mass, and in the range of 0.1% by mass to 30% by mass. If it exists in the range of 0.5 mass% or more and 10 mass% or less, it is most preferable.

  The first layer 31 is formed from, for example, a composition (second composition) containing the metal nanowire 4 and a resin component. In this case, the first layer 31 can be formed by a wet film forming method.

  The resin component in the second composition contains, for example, at least one of a thermoplastic resin and a reactive curable resin.

  When the resin component contains a thermoplastic resin, the thermoplastic resin may be, for example, a cellulose resin, a silicone resin, a fluororesin, an acrylic resin, a polyethylene resin, a polypropylene resin, a polyethylene terephthalate resin, a polymethyl methacrylate resin, a polystyrene resin, or a polyether. Sulfone resin, polyarylate resin, polycarbonate resin, polyurethane resin, polyacrylonitrile resin, polyvinyl acetal resin, polyamide resin, polyimide resin, diacryl phthalate resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl acetate resin, and these 1 type or more selected from the copolymer formed by polymerizing two or more types of monomers constituting the resin.

  When the resin component contains a reactive curable resin, the reactive curable resin contains, for example, at least one of a thermosetting resin and an ionizing radiation curable resin.

  The thermosetting resin contains at least one selected from, for example, phenol resin, urea resin, diallyl phthalate resin, melamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, silicon resin, and polysiloxane resin To do. The composition may contain a crosslinking agent, a polymerization initiator, a curing agent, a curing accelerator, a solvent, and the like as necessary together with the thermosetting resin.

  The ionizing radiation curable resin preferably contains a resin having an acrylate functional group. The resin having an acrylate functional group contains at least one selected from oligomers and prepolymers such as (meth) acrylates of polyfunctional compounds having a relatively low molecular weight. The polyfunctional compound contains, for example, one or more selected from polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and polyhydric alcohols.

  When the second composition contains an ionizing radiation curable resin, it is also preferable that the composition further contains a reactive diluent. Reactive diluents include, for example, ethyl (meth) acrylate, ethylhexyl (meth) acrylate, monofunctional monomers such as styrene, methylstyrene, N-vinylpyrrolidone, trimethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate , Tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di 1 type or more selected from the polyfunctional monomer of (meth) acrylate is contained.

  When the second composition contains a photocurable resin such as an ultraviolet curable resin as the ionizing radiation curable resin, it is preferable that the second composition further contains a photopolymerization initiator. The photopolymerization initiator contains one or more selected from, for example, acetophenones, benzophenones, α-amyloxime esters, and thioxanthones. When the second composition contains a photocurable resin, the second composition may further contain a photosensitizer in addition to the photopolymerization initiator or instead of the photopolymerization initiator. . The photosensitizer contains at least one selected from, for example, n-butylamine, triethylamine, tri-n-butylphosphine, and thioxanthone.

  The 2nd composition may contain a solvent if needed. As the solvent, for example, an organic solvent is used, water is used, or an organic solvent and water are used in combination. Examples of the organic solvent include alcohols such as methanol, ethanol and isopropyl alcohol (IPA); ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as ethyl acetate and butyl acetate; halogenated hydrocarbons; It is selected from aromatic hydrocarbons such as xylene, and mixtures thereof.

  The amount of the solvent in the second composition is appropriately adjusted so that the solid content can be uniformly dissolved or dispersed in the second composition. The solid content concentration in the composition is preferably in the range of 0.1 to 50% by mass, and more preferably in the range of 0.5 to 30% by mass.

  The first layer 31 can be formed by applying the second composition and further forming a film. In applying the second composition, an appropriate method such as a roll coating method, a spin coating method, or a dip coating method is employed. The technique for forming the second composition is appropriately selected according to the type of resin component and the like in the second composition. For example, when the second composition contains a thermosetting resin, the first layer 31 containing the metal nanowires 4 is formed by heating and thermosetting the second composition. For example, when the second composition contains an ionizing radiation curable resin, the second composition is cured by irradiating the second composition with ionizing radiation such as ultraviolet rays, so that the metal nanowires are cured. A first layer 31 containing 4 is formed.

  The thickness of the first layer 31 is not particularly limited, but is preferably in the range of 10 to 300 nm.

  The second layer 32 in the conductive layer 3 contains a blue compound. The blue compound is present dispersed in the second layer 32. In the present embodiment, the second layer 32 does not contain the metal nanowire 4.

  If a blue compound fully absorbs the component of the long wavelength region in light, there will be no restriction | limiting in particular in a blue compound. In order to sufficiently reduce the ratio of components in the long wavelength region in the light, it is particularly preferable that the blue compound has a maximum wavelength of light absorption within a wavelength range of 500 to 750 nm.

  The blue compound may contain either a dye or a pigment. Examples of the dye include anthraquinone dyes and azo dyes. Specific examples of the dye include trade name Kayaset Blue A2R, trade name Kayaset Blue N, trade name Kayaset Blue FR, and trade name Kayaset Blue A-S manufactured by Nippon Kayaku Co., Ltd. Examples of the pigment include cobalt blue (cobalt aluminate), cobalt stannate, cobalt chrome blue, cobalt-aluminum-silicon oxide, cobalt-zinc-silicon oxide, and manganese blue.

  The amount of the blue compound in the second layer 32 can be appropriately adjusted so that the ratio of components in the long wavelength region in the light is sufficiently reduced by the light passing through the second layer 32. In particular, in order to effectively suppress the milky face, the ratio of the blue compound to the metal nanowire 4 in the conductive layer 2 is preferably in the range of 10 to 80% by mass. Furthermore, in order to maintain good light transmittance of the conductive optical member 1 and to effectively suppress the change in the hue of light before and after passing through the conductive optical member 1, the ratio of the blue compound is 25 to 25%. If it is in the range of 50 mass%, it is more preferable.

  Moreover, it is preferable that the value of the mass ratio of the blue compound in the second layer 32 to the yellow compound in the adjustment layer 5 is in the range of 0.5-2. In this case, the change in the hue of light before and after passing through the conductive optical member 1 is particularly suppressed.

  Moreover, when the second layer 32 covers the first layer 31, the second layer 32 protects the first layer 31, so that deterioration such as oxidation of the metal nanowire 4 in the first layer 31 can be suppressed.

  The thickness of the second layer 32 is not limited, but is preferably in the range of 30 to 300 nm. If the thickness of the second layer 32 is 30 nm or more, the effect of protecting the first layer 31 is sufficiently obtained, and the effect of suppressing the detachment of the metal nanowires 4 from the first layer 31 is also obtained. If this thickness is 100 nm or more, it is more preferable. If the thickness of the second layer 32 is 300 nm or less, effects such as suppression of oxidation, suppression of sulfidation, and suppression of peeling due to friction and the like of the metal nanowire 4 are sufficiently obtained. Furthermore, if the thickness of the second layer 32 is 300 nm or less, even if the second layer 32 exists, the metal nanowires 4 in the first layer 31 are easily removed by the wet etching process. For this reason, an etching process is easily performed. If this thickness is 200 nm or less, it is more preferable. In this case, even if the first layer 31 is covered with the second layer 32, the electrical conductivity from the surface of the second layer 32 to the first layer 31 is kept good. It can function well as an electrode of a device or the like. It is particularly preferable if the thickness of the second layer 32 is in the range of 100 to 200 nm.

  The second layer 32 is formed from, for example, a composition (third composition) containing a blue compound and a resin component. In this case, the second layer 32 can be formed by a wet film forming method. When the second layer 32 containing the colorant is formed, the third composition contains the colorant. When the second layer 32 containing nanocarbon is formed, the third composition contains nanocarbon. The third composition may further contain an appropriate filler.

  The third composition is preferably a reactive curable resin composition, for example, preferably at least one of a thermosetting resin composition and an ionizing radiation curable resin composition.

  When the third composition is a thermosetting resin composition, the third composition includes, for example, phenol resin, urea resin, diallyl phthalate resin, melamine resin, unsaturated polyester resin, polyurethane resin, epoxy as a resin component. One or more thermosetting resins selected from resins, aminoalkyd resins, silicon resins, and polysiloxane resins are contained. A 3rd composition may contain a crosslinking agent, a polymerization initiator, a hardening | curing agent, a hardening accelerator, a solvent, etc. with a thermosetting resin as needed. In this case, the second composition 32 can be formed by applying the third composition onto, for example, the first layer 31 and then heating and thermosetting the third composition.

  When the third composition is an ionizing radiation curable resin composition, the third composition preferably includes, for example, a resin having an acrylate functional group as a resin component. Examples of the resin having an acrylate functional group include oligomers such as (meth) acrylates of a relatively low molecular weight polyfunctional compound, prepolymers, and the like. Examples of the polyfunctional compound include polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and polyhydric alcohols. It is also preferred that the third composition further contains a reactive diluent. Examples of reactive diluents include monofunctional monomers such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone, trimethylolpropane tri (meth) acrylate, and hexanediol (meth) acrylate. , Tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di The polyfunctional monomer of (meth) acrylate is mentioned.

  When the third composition is a photocurable resin composition such as an ultraviolet curable resin composition, the third composition preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include acetophenones, benzophenones, α-amyloxime esters, thioxanthones, and the like. The first composition may contain a photosensitizer in addition to the photopolymerization initiator or in place of the photopolymerization initiator. Examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, and thioxanthone. Such a third composition can be applied, for example, onto the first layer 31, and then the second composition 32 can be formed by irradiating the third composition with light such as ultraviolet rays and photocuring. .

  The second layer 32 may partially cover the surface of the first layer 31 located on the side opposite to the substrate 2. The metal nanowire 4 in the first layer 31 may penetrate through the second layer 32. In this embodiment, as shown in FIG. 1, irregularities are formed on the surface of the first layer 31 located on the side opposite to the substrate 2 due to the metal nanowires 4. For this reason, in the present embodiment, the second layer 32 partially covers the surface of the first layer 31 located on the side opposite to the substrate 2, and further the metal nanowires in the first layer 31. Part of 4 penetrates through the second layer 32. Of course, the second layer 32 may entirely cover the surface of the first layer 31 located on the side opposite to the substrate 2.

  The conductive layer 3 in the conductive optical member 1 forms an electrode or the like in an electronic device that requires optical characteristics such as a touch panel, an organic electroluminescence display panel, a plasma display panel, a liquid crystal display panel, a photoelectric conversion device, and the like. To be used.

  The conductive optical member 1 according to the present embodiment is incorporated in an electronic device as it is, for example, so that the conductive layer 3 in the conductive optical member 1 is used as an electrode or the like. Further, the conductive layer 3 and the adjustment layer 5 are peeled off from the conductive optical member 1, and the member made of the conductive layer 3 and the adjustment layer 5 is incorporated in an electronic device, so that the conductive layer 3 is used as an electrode or the like. May be.

  In an electronic device including the conductive optical member 1, the conductive optical member 1 transmits light that is emitted from the electronic device to the outside after passing through the adjustment layer 5 of the conductive optical member 1 and then through the conductive layer 3. As configured. For example, in an electronic device including the conductive optical member 1, as shown in FIG. 1, the back is positioned away from the conductive optical member 1 and at a position facing the first surface 33 of the conductive layer 3. A light source 7 such as a light is disposed. The light source 7 is configured to emit light toward the conductive optical member 1. The arrows in FIG. 1 indicate the direction of light irradiation from the light source 7 to the conductive optical member 1. In this electronic device, when light emitted from the light source 7 passes through the conductive optical member 1 and is emitted to the outside of the electronic device, this light passes through the adjustment layer 5 and then through the conductive layer 3. For this reason, as above-mentioned, a milky face is suppressed and the change of the hue of the light before and behind permeate | transmitting the electroconductive optical member 1 is also suppressed.

  Hereinafter, specific examples of the present invention will be described.

  The inventors produced conductive optical members and evaluated their performance as follows.

[Example 1]
A transparent polyethylene terephthalate film (thickness 125 μm) was prepared as a substrate.

  An adjustment layer was formed on this substrate as follows.

Acrylic resin is dissolved by adding and mixing 50.0 parts by mass of methyl ethyl ketone and 39.65 parts by mass of methyl isobutyl ketone to 1.2 parts by mass of acrylic resin (manufactured by Shin-Nakamura Chemical Co., Ltd., product number U-6LPA). Thus, a mixed solution was prepared. To this mixed solution was further added 0.15 parts by mass of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone, Ciba Geigy, product name Irgacure 184), and a yellow compound (manufactured by Nippon Kayaku Co., Ltd., trade name Kayaset). A yellow compound consisting of Yellow SF-G) was added and mixed well, followed by stirring and mixing in a constant temperature atmosphere at 25 ° C. for 30 minutes. This prepared the 1st composition for forming an adjustment layer. This first composition was applied to one surface of the substrate with a wire bar coater, dried at a temperature of 23 ° C. for 1 minute, and then dried at 100 ° C. for 2 minutes. Further, the first composition was cured by irradiating with ultraviolet rays under a condition of an accumulated ultraviolet ray amount of 500 mJ / cm ^{2 in} a nitrogen atmosphere (oxygen concentration of 500 ppm or less). Thereby, an adjustment layer having a thickness of 100 nm was formed.

  In addition, the usage-amount of the yellow compound was adjusted so that the mass ratio of the yellow compound in the adjustment layer with respect to the metal nanowire in a conductive layer might turn into the value shown in the table | surface below. The yellow compound used in this example has a maximum value of light absorption within a wavelength range of 380 to 500 nm.

  Next, a conductive layer was formed on the adjustment layer as follows.

  First, the first layer was formed as follows.

  3 parts by mass of methyl cellulose (M7140) manufactured by Sigma-Aldrich was dissolved in 200 parts by mass of ion-exchanged water to prepare a methyl cellulose solution.

  Silver nanowires having an average diameter of 60 nm and an average length of 5 μm were prepared as metal nanowires. In addition, this silver nanowire was produced by the method according to the method as described in a well-known paper (Materials Chemistry and Physics vol.114 p333-338 "Preparation of Ag nanorods with high yield by polyol process"). By dispersing this silver nanowire in ion-exchanged water, a dispersion containing 3.0% by mass of silver nanowire was prepared.

  By mixing the methylcellulose solution and the dispersion, a second composition having a methylcellulose ratio of 0.25% by mass and a silver nanowire ratio of 0.15% by mass was prepared.

  This second composition was applied onto the adjustment layer with a wire bar coater, left to dry at 23 ° C. for 1 minute, and then heated to dry at 100 ° C. for 2 minutes. As a result, a first layer having a thickness of about 60 to 120 nm was formed on the adjustment layer.

  Next, a second layer was formed on the first layer as follows.

  Acrylic resin is dissolved by adding and mixing 50.0 parts by mass of methyl ethyl ketone and 39.65 parts by mass of methyl isobutyl ketone to 1.2 parts by mass of acrylic resin (manufactured by Shin-Nakamura Chemical Co., Ltd., product number U-6LPA). Thus, a mixed solution was prepared. 0.15 parts by mass of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone, manufactured by Ciba Geigy, product name Irgacure 184) was further added to this mixed solution, and further a blue compound (manufactured by Nippon Kayaku Co., Ltd., trade name) A third composition was prepared by adding Kayaset Blue A2R) and mixing well.

This third composition was applied onto the conductive layer with a spin coater, dried by leaving it at 23 ° C. for 2 minutes, and then heated at 100 ° C. for 2 minutes. Subsequently, the third composition was irradiated with ultraviolet rays in a nitrogen atmosphere (oxygen concentration of 500 ppm or less) under the condition of an ultraviolet ray cumulative amount of 500 mJ / cm ² . Thereby, a second layer having a thickness of 120 nm was formed.

  In addition, the usage-amount of a blue compound was adjusted so that the mass ratio of the blue compound in a 2nd layer with respect to the metal nanowire in a conductive layer might become a value shown in the table | surface below. The blue compound used in this example has a maximum value of light absorption in the wavelength region of 500 to 750 nm.

  As described above, a conductive optical member including a base material, an adjustment layer, and a conductive layer was obtained.

[Examples 2 and 3]
In Example 1, when the third composition was prepared, the amount of the blue compound used was adjusted so that the mass ratio of the blue compound in the second layer to the metal nanowires in the conductive layer was the value shown in the table below. changed. Other than that was the same conditions as Example 1, and obtained the electroconductive optical member provided with a base material, an adjustment layer, and a conductive layer.

[Examples 4 and 5]
In Example 1, when the first composition was prepared, the amount of yellow compound used was changed so that the mass ratio of the yellow compound in the adjustment layer to the metal nanowires in the conductive layer would be the value shown in the table below. did. Other than that was the same conditions as Example 1, and obtained the electroconductive optical member provided with a base material, an adjustment layer, and a conductive layer.

[Comparative Example 1]
In Example 1, a yellow compound and a blue compound were not used. Other than that was the same conditions as Example 1, and obtained the electroconductive optical member provided with a base material, an adjustment layer, and a conductive layer.

[Comparative Example 2]
In Example 1, no yellow compound was used. Other than that was the same conditions as Example 1, and obtained the electroconductive optical member provided with a base material, an adjustment layer, and a conductive layer.

[Comparative Example 3]
In Example 1, no blue compound was used. Other than that was the same conditions as Example 1, and obtained the electroconductive optical member provided with a base material, an adjustment layer, and a conductive layer.

[Evaluation test]
1. Luminance (milky face evaluation)
The luminance of the reflected light when light was irradiated toward the conductive layer of the conductive optical member obtained in each example and comparative example was measured with a color luminance meter (manufactured by Konica Minolta, model number CS-2000). In the measurement, a xenon lamp was used as a light source, the incident angle of incident light was set to 30 °, the reflection angle of reflected light was set to 0 °, and the luminance of the reflected light was measured with a color luminance meter. The results are shown in the table below. The values shown in the table are relative values derived from the measured luminance values. It can be determined that the milky face is suppressed as the value is lower.

2. Transmission chromaticity measurement The chromaticity a ^* and b ^* of transmitted light that passes through the base material, the adjustment layer, and the conductive layer in the order of the conductive optical members obtained in each of the examples and comparative examples was changed to JIS Z8722 and JIS Z8729. Measured in conformity. A spectrocolorimeter (manufactured by Konica Minolta, model number CMD-3600d) was used as a measuring device, a CIE standard C light source was used as a light source, and measurement was performed under a 2 ° visual field condition. The results are shown in the table below. It can be determined that the closer the values of chromaticity a ^* and b ^* are to 0, the smaller the change in the hue of light before and after passing through the conductive optical member.

3. Total Light Transmittance Measurement The total light transmittance of the conductive optical members obtained in each Example and Comparative Example was measured using a haze meter (Nippon Denshoku Industries Co., Ltd.) using a D65 light source defined by CIE in accordance with JIS K7361. Measurement was made with a model number NDH2000 manufactured by Co., Ltd. The results are shown in the table below.

4). Sheet resistance The sheet resistance on the surface of the conductive layer of the conductive optical member obtained in each Example and Comparative Example was measured using a non-contact type resistivity measuring device (model number NC-10, manufactured by Napson Corporation). did. The results are shown in the table below.

DESCRIPTION OF SYMBOLS 1 Conductive optical member 2 Base material 3 Conductive layer 31 1st layer 32 2nd layer 4 Metal nanowire 5 Adjustment layer

Claims (4)

A substrate having light permeability; and a conductive layer, wherein the conductive layer has a first surface and a second surface located on the opposite side of the first surface, and the substrate is A conductive optical member located on the second surface side with respect to the conductive layer,
The conductive layer contains metal nanowires and a blue compound, and the blue compound is unevenly distributed on the first surface side in the conductive layer,
The conductive optical member further includes an adjustment layer positioned on the second surface side with respect to the conductive layer, and the adjustment layer contains a yellow compound. The conductive layer includes a first layer and a second layer located on the opposite side of the adjustment layer from the first layer, and the metal nanowires are dispersed in the first layer, The conductive optical member according to claim 1, wherein a blue compound is dispersed in the second layer. The conductive optical member according to claim 1, wherein the metal nanowire contains a silver nanowire. The conductive optical member according to claim 1, wherein the adjustment layer is interposed between the base material and the conductive layer.

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