JP6520133B2 - Laminate, method of manufacturing conductive substrate using the same, and method of manufacturing electronic device - Google Patents

Description

  The present invention relates to a laminate having a conductive layer, a method of producing a conductive substrate using the same, and a method of producing an electronic device.

  Conventionally, as a method of forming a metal layer as a conductive layer or a decoration layer on a substrate, for example, a method using a transfer sheet is known (see Patent Documents 1 to 5).

  Patent Document 1 proposes a method of forming an antenna terminal portion using a metal deposition layer transfer sheet in which a protective layer, a metal deposition layer, and an adhesive layer are laminated on a base material. In the case of the metal deposition layer as described in Patent Document 1, heat resistance is required for the underlayer of the metal deposition layer. Therefore, when an inexpensive general-purpose plastic film such as a PET film is used as the substrate, there is a problem that the film forming process, the metal type, the film thickness, etc. are limited because the heat resistance is low. The heat resistance is secured by forming an. On the other hand, although a highly heat resistant substrate such as a polyimide film, a PEN film, or a glass film can be used as a substrate, these substrates are expensive and suitable as a substrate of a transfer sheet to be peeled and removed. It can not be said that

  Patent Document 2 has a release sheet as a substrate, an insulator layer provided on the release sheet, and a metal foil disposed in contact with the insulator layer, and the metal foil is used for the release sheet. A metal foil sheet for transfer is proposed which is attached by the attraction of static electricity generated between it and the insulator layer. In the case of the metal foil as in Patent Document 2, there is a problem that the adhesion with the substrate is low, and the adhesion is secured by forming a resin layer such as an insulator layer on the substrate.

  Patent Document 3 further uses a thermal transfer film having a resin film, a metal foil provided on the surface of the resin film via an adhesive, and a thermosetting adhesive applied on the metal foil. Production of a metal foil fuse in which a metal foil is transferred onto an insulating substrate via a thermosetting adhesive using a transfer mold having a convex fuse element pattern, into a pattern shape of the transfer mold fuse element The law is proposed. Also in this case, the adhesion of the resin film and the metal foil is secured by providing the metal foil on the surface of the resin film via an adhesive.

  The transfer sheet is required to have foil breakage. However, since the metal deposition layer and the metal foil are ductile, burrs are generated at the time of transfer, and there is a problem that the foil cutting property is poor. In addition, in the metal deposition layer, crystal grains may grow large, and in such a case, the foil-breakability naturally deteriorates. Although a method has been proposed in which the transfer sheet is sandwiched between molds having asperities, stressed and cut, and then transfer is performed in order to improve foil breakage, the process becomes complicated.

  In general, metal has a high thermal conductivity, so heat is easily diffused in a metal vapor deposition layer or metal foil, energy required for transfer tends to be large, and the shape of the transfer sheet may be distorted.

  Also, when transferring a transfer sheet to a transfer target, in order to adhere the metal deposition layer or metal foil to the transfer target, for example, when using a heat seal agent such as a thermoplastic resin as an adhesive layer, thermoplasticity It heats above the glass transition temperature of resin. At this time, the adhesion between the transfer target and the metal deposition layer or metal foil is larger than the adhesion between the base material and the metal deposition layer or metal foil, whereby thermal transfer is realized. In this case, since there is a limit in adjusting the above-mentioned adhesion with the heat sealing agent alone, the adhesion between the material to be transferred and the metal deposition layer or metal foil is determined by the adhesion of the substrate to the metal deposition layer or metal foil Although it has been proposed to form fine irregularities such as roughening the contact surface of the metal deposition layer or the metal foil with the adhesive layer in order to increase the force, for example, the process becomes complicated.

  In Patent Document 4, using a donor element in which a light absorption layer and a metal nanoparticle layer are laminated on a donor substrate as a base material, the donor element and the receiving substrate are disposed in contact, and a laser is irradiated from the donor element side. A method has been proposed to form a pattern of electrical conductors on a receiving substrate by annealing and transferring the metal nanoparticle layer. However, because this method uses metal nanoparticles as the conductive material, the electrical resistance at the interface between particles is a problem, and in order to achieve the desired conductivity, annealing the metal nanoparticles at high temperature is necessary. Therefore, the substrate needs to withstand the high heat of laser annealing, the substrate is limited, and it becomes difficult to use inexpensive general-purpose plastic films. In addition, it is necessary to use a highly heat-resistant and expensive base material as the base material to be peeled and removed, which increases the cost.

On the other hand, according to Patent Document 5, using a transfer sheet in which a sintered body layer of metal ultrafine particles is formed on a base material, the metal ultrafine particles are baked on each other on a transfer substrate having an adhesive layer formed on the surface. A method has been proposed for forming a wiring pattern consisting of a body layer. In this method, by using metal ultrafine particles, sintering can be performed even at a relatively low temperature.
However, the conductivity may be lowered by oxidation of the metal ultrafine particles, and the conductivity may be lowered when transferring the sintered body layer of the metal ultrafine particles to the transfer substrate.

JP, 2007-324641, A Japanese Patent Application Laid-Open No. 7-101198 Unexamined-Japanese-Patent No. 5-314888 JP 2008-541481 gazette JP 2004-247572 A

  The present invention has been made in view of the above problems, and is a laminate capable of transferring a porous conductive layer excellent in foil severability and transferability and having good conductivity, and a conductive substrate using the same. The main object of the present invention is to provide a method of manufacturing the same and a method of manufacturing an electronic device.

  In order to achieve the above object, the present invention is characterized by having a substrate, a porous conductive layer formed on the substrate, and an adhesive layer formed on the porous conductive layer. Provide a laminate.

In the present invention, the component derived from the adhesive layer, for example, the resin contained in the adhesive layer can be introduced into the pores of the porous conductive layer. Therefore, thermal diffusion can be made less likely to occur, which is advantageous for thermal transfer. Moreover, the adhesiveness of a porous conductive layer and an adhesive layer can be improved, and the outstanding transferability can be obtained. Furthermore, the porous conductive layer can be protected by the resin contained in the adhesive layer, and the oxidation of the porous conductive layer at the time of transfer can be suppressed, and the decrease in conductivity can be suppressed.
Further, in the present invention, since the porous conductive layer is provided, brittleness is imparted, and excellent foil breakage and resolution can be obtained. In addition, since the porous conductive layer can be formed by sintering metal particles at a low temperature, it is less likely to damage the base material, and it is not necessary to use a base material having high heat resistance, and a base having low heat resistance Materials can also be used.
Moreover, an electroconductive base material can be easily produced by using the laminated body of this invention.

  Further, in the present invention, the substrate is preferably a resin substrate. As described above, in the present invention, a substrate with low heat resistance can also be used, and it is very useful in that an inexpensive general purpose plastic resin substrate can be used.

  In the present invention, a protective layer may be formed between the base and the porous conductive layer. After transfer, the porous conductive layer can be protected by a protective layer. In addition, the porous conductive layer can be insulated by providing the insulating protective layer.

  The present invention further includes a preparation step of preparing the above-mentioned laminate, and a transfer step of transferring the adhesive layer and the porous conductive layer of the above-mentioned stack onto the transferred substrate. Provide a manufacturing method of

  In the present invention, since the above-mentioned laminate is used, it is excellent in foil breakage, resolution and transferability. In addition, it is possible to obtain a porous conductive layer having good conductivity even after transfer. Furthermore, the conductive substrate can be easily produced.

  In the above invention, in the transfer step, the pattern of the adhesive layer and the porous conductive layer of the laminate may be transferred onto the transfer substrate. A conductive substrate in which a pattern of a porous conductive layer is formed on a transferred substrate can be obtained.

  In the present invention, a preparation step of preparing the above-mentioned laminate, the above-mentioned laminate is disposed in a forming die, and a molten resin for receiving substrate is injected into the forming die to solidify it. A method of manufacturing a conductive substrate comprising forming and transferring steps of transferring the laminate to the substrate to be transferred at the same time as forming the conductive layer, and peeling off the substrate of the laminate. provide.

  In the present invention, since the above-mentioned laminate is used, it is excellent in foil breakage and transferability. In addition, it is possible to obtain a porous conductive layer having good conductivity even after transfer. Furthermore, a three-dimensional conductive substrate can be easily produced.

  Furthermore, the present invention provides a method for producing an electronic device, comprising the step of producing a conductive substrate by the method for producing a conductive substrate described above.

  In the present invention, since the conductive substrate is produced by the method for producing a conductive substrate described above, a porous conductive layer having good conductivity can be formed. Further, for example, in the case of forming a pattern of a porous conductive layer, a pattern of high resolution can be formed.

  The laminate of the present invention is excellent in foil-breakability and transferability, and exhibits the effect of being able to transfer a porous conductive layer with good conductivity.

It is a schematic sectional drawing which shows an example of the laminated body of this invention. It is process drawing which shows an example of the manufacturing method of the electroconductive base material of this invention. It is process drawing which shows the other example of the manufacturing method of the electroconductive base material of this invention. It is a schematic sectional drawing which shows the laminated body of this invention, and the other example of a conductive base material. It is a schematic sectional drawing which shows the laminated body of this invention, and the other example of a conductive base material. It is process drawing which shows the other example of the manufacturing method of the electroconductive base material of this invention. It is a schematic sectional drawing which shows the laminated body of this invention, and the other example of a conductive base material. It is process drawing which shows the other example of the manufacturing method of the electroconductive base material of this invention. It is process drawing which shows the other example of the manufacturing method of the electroconductive base material of this invention.

  Hereinafter, the laminate, the method for producing a conductive substrate, and the method for producing an electronic device of the present invention will be described in detail.

A. Laminate The laminate of the present invention is characterized by having a substrate, a porous conductive layer formed on the substrate, and an adhesive layer formed on the porous conductive layer. .

The laminate of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing an example of the laminate of the present invention. As shown in FIG. 1, the laminate 1 includes a base 2, a porous conductive layer 3 formed on the base 2, and an adhesive layer 4 formed on the porous conductive layer 3. There is.

  FIGS. 2 (a) to 2 (c) are process drawings showing an example of a method for producing a conductive substrate using the laminate of the present invention, which is an example using the laminate shown in FIG. First, as shown to Fig.2 (a), the laminated body 1 and the to-be-transferred base material 11 are prepared. Next, as shown in FIG. 2B, the adhesive layer 4 of the laminate 1 and the transfer receiving substrate 11 are disposed in contact with each other, and thermocompression bonding is performed from the laminate 1 side. Thereafter, as shown in FIG. 2 (c), the base material 2 is peeled off. As a result, the adhesive layer 4 and the porous conductive layer 3 are transferred to the transferred substrate 11 in the thermocompression-bonded area, and the conductive substrate 10 is obtained.

  Fig.3 (a)-(c) is process drawing which shows the other example of the manufacturing method of the electroconductive base material which used the laminated body of this invention, and is an example using the laminated body shown in FIG. First, as shown to Fig.3 (a), the laminated body 1 and the to-be-transferred base material 11 are prepared. Next, as shown in FIG. 3 (b), the adhesive layer 4 of the laminate 1 and the transferred substrate 11 are disposed in contact with each other, and thermocompression bonding is performed from the laminate 1 side. At this time, thermal compression is applied partially by the thermal head 12 or the like of the thermal head printer. Thereafter, as shown in FIG. 3C, the substrate 2 side is peeled off. Thereby, the adhesive layer 4 and the porous conductive layer 3 are transferred to the transferred substrate 11 in the thermocompression-bonded area, and the conductive substrate 10 having the pattern of the adhesive layer 4 and the porous conductive layer 3 is obtained.

  In the present invention, a component derived from the adhesive layer, for example, a resin contained in the adhesive layer can be introduced into the pores of the porous conductive layer, and a mixture of components apparently derived from the porous conductive layer and the adhesive layer As a result, thermal diffusion can be made less likely to occur. Therefore, when the laminate of the present invention is transferred to a transfer receiving substrate, the heat does not easily escape, so it is not necessary to heat excessively, which is advantageous for heat transfer.

  Further, in the present invention, as described above, since the component derived from the adhesive layer can be introduced into the pores of the porous conductive layer, not only the surface area where the porous conductive layer and the adhesive layer contact is increased. The adhesion of the porous conductive layer and the adhesive layer can be enhanced by the anchor effect. Therefore, when the laminate of the present invention is transferred to a transfer-receiving substrate, the adhesive layer and the porous conductive layer can be transferred well to the transfer-receiving substrate, and excellent transferability can be obtained.

  Further, as described later, in the porous conductive layer, the metal particles are sintered and fused to each other, so that the region in which the component derived from the adhesive layer is intruded in the pores of the porous conductive layer is also conductive. Contribute to Therefore, the adhesion to the adhesive layer can be enhanced without reducing the conductivity.

  In addition, the conductivity of the conductive material such as metal or metal oxide may be lowered by oxidation, and when transferring the laminate of the present invention to a substrate to be transferred, the conductivity of the porous conductive layer may be reduced. There is a risk that the sex may decline. On the other hand, in the present invention, as described above, since the resin contained in the adhesive layer can be introduced into the inside of the pores of the porous conductive layer, the laminate of the present invention is transferred to the transferred substrate In this case, the porous conductive layer can be protected by the resin contained in the adhesive layer, and the oxidation of the porous conductive layer can be suppressed. Accordingly, the decrease in conductivity of the porous conductive layer at the time of transfer can be suppressed.

  Further, in the present invention, since the porous conductive layer is porous and therefore provided with brittleness, unlike the conventional vapor deposition layer, the occurrence of burrs during transfer is small and large crystal grains are not included. Therefore, good foil breakage can be obtained. Furthermore, as illustrated in FIGS. 3 (a) to 3 (c), in the case of transferring the pattern of the adhesive layer and the porous conductive layer of the laminate of the present invention to a transfer substrate, it can.

  Here, it is known that metal particles sinter at a low temperature when their particle diameter is reduced. In the present invention, the porous conductive layer is formed by sintering metal particles at a low temperature by utilizing such a property that when such metal particles are nanoparticulated, they are sintered at a temperature significantly lower than the melting point of the metal particles. It can be formed. Therefore, there is no need to use a highly heat-resistant substrate with little damage to the substrate, and a low heat-resistant substrate can also be used. In particular, it is very useful in that inexpensive general-purpose plastic resin substrates such as polyethylene terephthalate can be used.

  In the present invention, the porous conductive layer can be formed, for example, by applying a metal particle dispersion containing metal particles on a substrate and baking it, and it has a good adhesion to the substrate. A conductive layer can be obtained. Therefore, it is not necessary to form another layer on the substrate or to apply a surface treatment to improve the adhesion.

  In addition, since the porous conductive layer can be formed on the transferred substrate by transferring the laminate of the present invention to the transferred substrate, a porous conductive layer is conventionally formed as the transferred substrate. Substrates that have been difficult to do can also be used. Therefore, it is possible to obtain an inexpensive general-purpose plastic resin substrate such as polyethylene terephthalate or a conductive substrate in which a porous conductive layer is formed on a paper substrate or the like. Furthermore, it is also possible to form a porous conductive layer on a three-dimensional object to be transferred.

  Hereinafter, each structure in the laminated body of this invention is demonstrated.

1. Porous Conductive Layer The porous conductive layer in the present invention is formed on a substrate.

  Here, the porous conductive layer refers to a conductive layer having a large number of pores, and the surface area is larger than that of a non-porous conductive layer having the same volume.

As a conductive material which comprises a porous conductive layer, a metal and a metal oxide can be mentioned, for example. The conductive material constituting the porous conductive layer may be one type or two or more types.
Among them, metals are preferred. This is because metal particles can be sintered at lower temperatures to form a porous conductive layer.

Examples of the metal include gold, silver, copper, nickel, platinum, palladium, molybdenum, aluminum, antimony, tin, chromium, indium, gallium, germanium, zinc, titanium, lead and the like. Among them, silver and copper are preferable in terms of conductivity and cost. The metal may be one type or two or more types.
Examples of metal oxides include indium tin oxide and antimony-doped tin oxide.

  The shape of the pores in the porous conductive layer is not particularly limited as long as the component derived from the adhesive layer can be introduced into at least a part of the pores. It is preferable that at least the surface on the adhesive layer side of the porous conductive layer has a communicating hole in which a large number of holes are connected to each other.

The porosity of the porous conductive layer is not particularly limited as long as conductivity and adhesion can be appropriately adjusted to a compatible range. Specifically, the porosity of the porous conductive layer is preferably in the range of 5% to 50%, more preferably in the range of 10% to 45%, and particularly preferably in the range of 15% to 40%. It is preferably inside. If the porosity is too large, the adhesion between the porous conductive layer and the substrate may be reduced. Moreover, when the porosity is too small, the above-mentioned effect by the component derived from an adhesion layer getting into the inside of the hole of a porous conductive layer may not fully be acquired.
In addition, the porosity of a porous conductive layer represents the part in which the material which comprises a porous conductive layer does not exist, and the part in which the component derived from an adhesive layer is mixed is also contained.

The porosity can be confirmed from a scanning electron microscope (SEM) image of the cross section of the porous conductive layer before the formation of the adhesive layer. Specifically, the area of the hole and the area of the porous conductive layer are respectively calculated from the obtained SEM image, and the area of the hole is divided by the area of the porous conductive layer to obtain the porosity in the above cross section. be able to. In addition, the porosity is calculated from the porous conductive layer excluding the substrate, and the pores at the interface between the substrate and the porous conductive layer are included toward the porous conductive layer.
The porosity can also be confirmed from a scanning electron microscope (SEM) image of the cross section of the laminate. Specifically, the area of the hole, the area of the component derived from the adhesive layer, and the area of the porous conductive layer are calculated from the obtained SEM image, and the area of the pore and the area of the component derived from the adhesive layer are calculated. The porosity in the cross section can be determined by dividing the total by the area of the porous conductive layer.
According to the size of the laminate, the porosity is appropriately determined similarly for a plurality of cross sections, and the average value is taken as the porosity of the porous conductive layer.
The porosity can be appropriately adjusted according to the particle diameter of the metal particles used in the metal particle dispersion, the type of the dispersing agent, the firing conditions, and the like in the formation method of the porous conductive layer described later.

  The porous conductive layer 3 may be formed on the entire surface of the substrate 2 as illustrated in FIG. 1 and is formed in a pattern on the substrate 2 as illustrated in FIG. 4A. It is also good. When the porous conductive layer 3 is formed in a pattern on the base material 2 as shown in FIG. 4 (a), the laminate 1 is shown in FIG. 4 (b) without being partially transferred. Thus, the pattern of the porous conductive layer 3 can be transferred onto the transferred substrate 11.

  The thickness of the porous conductive layer is about 0.01 μm to 50 μm, preferably in the range of 0.05 μm to 10 μm, and particularly preferably in the range of 0.1 μm to 5 μm.

As a method of forming the porous conductive layer, a method of coating a metal particle dispersion containing metal particles on a substrate and baking it is used.
In the specification of the present application, metal particles include particles in an alloy state, particles of a metal compound, and the like in addition to particles in a metal state.

As a metal particle, it can select suitably from metal particles which produce conductivity after calcination, and can be used.
As a metal which comprises metal particle, gold, silver, copper, nickel, platinum, palladium, molybdenum, aluminum, antimony, tin, chromium, indium, gallium, germanium, zinc, titanium, lead etc. are mentioned, for example. Among them, silver and copper are preferable in terms of conductivity and cost. The metal constituting the metal particles may be one type or two or more types. Moreover, you may use that by which 2 or more types of metals form the core-shell structure, and the thing in which the surface of the particle | grains of a metal state is oxidized or nitrided etc are used. The metal particles may be oxidized at the surface or oxidized to the inside.
Moreover, as a metal compound which comprises the particle | grains of a metal compound, a metal oxide, a metal nitride, a metal hydride, a metal hydroxide, an organic metal compound etc. are mentioned, for example. It is preferable that these metal compounds are decomposed at the time of firing to be in a metal state. For example, particles of metal compounds which exhibit conductivity by reduction, specifically particles of metal compounds such as cuprous oxide, cupric oxide, silver oxide, copper nitride, copper hydride and the like can be mentioned. Moreover, as a metal oxide, an indium tin oxide, an antimony dope tin oxide, etc. are mentioned, for example.
The metal particles may be used alone or in combination of two or more.
Among them, particles in the metallic state are preferred. This is because particles in the metallic state can be sintered at lower temperatures to form a porous conductive layer.

  The metal particles are preferably metal nanoparticles. That is, the porous conductive layer is preferably a sintered body of metal nanoparticles. When a metal particle dispersion containing metal nanoparticles is applied and fired to form a porous conductive layer, the pore diameter and the crystal grain size can be controlled to a range suitable for foil breakage. .

The average particle diameter of the metal particles is preferably in the range of 1 nm to 200 nm, and more preferably in the range of 2 nm to 150 nm, particularly preferably in the range of 2 nm to 100 nm. When the average particle diameter is in the above range, the dispersion stability of the metal particle dispersion used when forming the porous conductive layer is good, and the conductivity when forming the porous conductive layer is good, In addition, the melting point is maintained low, sufficient sintering is possible, and high conductivity is obtained.
Here, the average particle size of the metal particles is the average primary particle size of the metal particles in the metal particle dispersion, and can be measured from an observation image by a transmission electron microscope.

  As a method of preparing metal particles, for example, physical methods obtained by grinding metal powder or metal oxide powder by mechanochemical method etc .; such as CVD method, vapor deposition method, sputtering method, thermal plasma method, laser method Chemical dry methods include thermal decomposition methods, chemical reduction methods, electrolytic methods, ultrasonic methods, laser ablation methods, supercritical fluid methods, chemical wet methods such as microwave synthesis methods and the like.

  The resulting metal particles are converted to a metal particle dispersion, so that the metal particles may be treated with a water-soluble polymer compound such as polyvinyl pyrrolidone or a protective agent such as a graft copolymer compound, a surfactant, a metal or metal oxide. It is preferable to coat with a compound having a thiol group, an amino group, a hydroxyl group or a carboxyl group which interacts with the substance. Further, depending on the method of synthesizing metal particles, the thermal decomposition product or oxide of the raw material may protect the particle surface and contribute to the dispersibility. In the case of a wet method such as a thermal decomposition method or a chemical reduction method, a reducing agent or the like may act as a protective agent for metal particles as it is. Also, in order to enhance the dispersion stability of the metal particle dispersion, the surface treatment of the metal particles is carried out, or a dispersant comprising a polymer compound, an ionic compound, a surfactant, etc. is added to the metal particle dispersion. May be

  The dispersion medium used for the metal particle dispersion is not particularly limited as long as the metal particles can be dispersed, and, for example, water or an organic solvent can be used. Examples of the organic solvent include alcohols, ketones, esters, ethers, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons and the like.

  Further, if necessary, a viscosity modifier, a surface tension modifier, a stabilizer or the like may be added to the metal particle dispersion.

  The solid content concentration of the metal particle dispersion is preferably in the range of 5% by mass to 95% by mass, and more preferably in the range of 10% by mass to 90% by mass, particularly in the range of 15% by mass to 85% by mass Is preferred. When the solid concentration is in the above range, sufficient conductivity is obtained, the viscosity is sufficiently low, and application of the metal particle dispersion to a substrate is easy.

When applying the metal particle dispersion onto the substrate, the metal particle dispersion may be applied over the entire surface of the substrate, or the metal particle dispersion may be applied in a pattern on the substrate.
As a method of applying the metal particle dispersion onto the substrate, for example, gravure printing, screen printing, spray coating, spin coating, comma coating, bar coating, knife coating, die coating, offset printing, flexographic printing, inkjet printing, dispenser Printing etc. can be mentioned. In the case of applying the metal particle dispersion in a pattern on the substrate, gravure printing, flexographic printing, screen printing, and inkjet printing are preferable from the viewpoint that fine patterning can be performed.

  After application of the metal particle dispersion, drying may be performed by a conventional method. For example, the drying method which heats at about 80 to 140 degreeC temperature for about 0.1 to 20 minutes using a common oven etc. is mentioned. The thickness of the coated film after drying can be controlled by adjusting the coating amount, the average particle diameter of the metal particles, etc., but is usually about 0.01 μm to 100 μm, preferably 0.1 μm to 50 μm. It is in the range.

As a method of baking the coating film of the metal particle dispersion liquid, any method that can sinter metal particles may be used, and a general baking method can be applied. For example, methods using heat treatment, light treatment, plasma treatment, and the like can be mentioned. By firing the coating, a porous conductive layer made of a sintered body of metal particles is obtained.
Examples of the heat treatment include hot plate heating, hot air heating, and a hot press method using a heat plate or a heat roll.
Examples of the light processing include laser processing, ultraviolet lamp processing, infrared lamp processing, far infrared lamp processing, flash light lamp processing and the like.
Plasma treatment is a treatment that ionizes a gas such as hydrogen, carbon monoxide, ammonia, or alcohol that exhibits reducibility to form a plasma state, and generates a highly reactive active species. For example, electron cyclotron resonance (ECR) plasma And capacitively coupled plasma, inductively coupled plasma, atmospheric pressure plasma, microwave plasma, surface wave plasma generated by application of microwave energy, and the like. Among them, surface wave plasma treatment is preferable.
In addition, said baking method can be used combining 2 or more types.

  The microwave surface wave plasma has characteristics of high plasma density and low electron temperature, and can bake the coating film at a low temperature and in a short time, and form a dense and smooth porous conductive layer. Can. The surface wave plasma is irradiated with plasma having a uniform density in the plane with respect to the surface to be treated. As a result, as compared with other baking methods, non-uniform films are less likely to be formed, such as sintering of metal particles partially progressing in the plane, and grain growth can be prevented. Dense and smooth film is obtained. In addition, since it is not necessary to provide an electrode in the in-plane processing chamber, contamination of impurities derived from the electrode can be prevented, and damage to the processing material due to abnormal discharge can be prevented. Furthermore, when using a resin base material, damage to the resin base material is small, and damage to other layers is also small.

  In addition, microwave surface wave plasma is suitable for enhancing the adhesion of the porous conductive layer to the resin substrate. The reason for this is presumed to be that microwave surface wave plasma is likely to generate polar functional groups such as hydroxyl groups and carboxyl groups at the interface between the base and the porous conductive layer. In particular, when a plasma generated under a reducing gas atmosphere is used for a polyester substrate, the plasma of a gas having a reducing gas reacts with the ester bond of the substrate, and the interface side of the substrate is changed. It is inferred that adhesion occurs at the interface between the porous conductive layer and the substrate due to the occurrence of quality and generation of a large number of highly polar reactive groups. Therefore, as compared with the conventional method in which the substrate surface is roughened by plasma treatment etc. in advance to improve the adhesion to the porous conductive layer as in the prior art, the substrate and the porous conductive film are also electrically conductive. It is excellent in the point with high adhesiveness with a layer.

  In addition, about the conditions of microwave surface wave plasma, the conditions of Unexamined-Japanese-Patent No. 2010-86825 can be applied, for example.

As an atmosphere at the time of baking, it selects suitably according to the kind of conductive material which comprises a porous conductive layer.
When forming the porous conductive layer containing metal, it is preferable to set it as the atmosphere of an inert gas or reducing gas, and it is preferable to set it as a reducing gas especially. In the case of a reducing gas atmosphere, oxides present on the surface of the metal particles can be reduced and removed to form a highly conductive porous conductive layer. Therefore, when forming a porous conductive layer containing a metal, metal particles whose surface is oxidized or metal particles whose inside is oxidized can be used as the metal particles.

As a reducing gas, hydrogen, carbon monoxide, ammonia, and these mixed gas etc. are mentioned, for example. Among them, hydrogen gas is preferable. Hydrogen gas is suitable for the removal of the organic substance adhering to the metal particle surface.
The reducing gas may be mixed with an inert gas such as nitrogen, helium, argon, neon, krypton or xenon. In this case, there are effects such as easy generation of plasma.

  On the other hand, in the case of forming a porous conductive layer containing a metal oxide, an atmosphere containing an inert gas such as nitrogen or argon and oxygen as needed may be used.

Furthermore, in the case of forming a porous conductive layer containing copper, a method using hydrogen plasma or nitrogen plasma is preferable. In particular, by using hydrogen plasma, a specific resistance of about 3 × 10 ⁻⁶ Ω · cm to 3 × 10 ⁻⁵ Ω · cm can be obtained, and a porous conductive layer having good adhesion to a substrate is formed. Because you can do it.

The firing temperature may be any temperature at which the metal particles can be sintered, and is appropriately selected according to the type of the metal particles, the particle diameter, the firing method, and the like. Among them, the firing temperature is preferably equal to or lower than the heat resistance temperature of the substrate, and in the case of using silver particles as an example, the range of 100 ° C. to 150 ° C. is preferable.
The firing time is appropriately selected according to the type of metal particles, the firing method, and the like. For example, when firing silver particles by heat treatment, the firing time is preferably in the range of 10 minutes to 120 minutes, and more preferably in the range of 15 minutes to 40 minutes. Further, for example, when the copper particles are fired by hydrogen plasma, the firing time is preferably in the range of 1 minute to 10 minutes, and more preferably in the range of 2 minutes to 5 minutes.

2. Adhesive Layer The adhesive layer in the present invention is formed on the above-mentioned porous conductive layer. The adhesive layer has a function of adhering the porous conductive layer and the transferred substrate when the laminate of the present invention is transferred to the transferred substrate.

  Examples of the material of the adhesive layer include thermoplastic resins and photosensitive resins whose tackiness or adhesiveness is reduced by light irradiation.

  The thermoplastic resin is not particularly limited as long as it can bond the porous conductive layer and the transferred substrate, and is appropriately selected according to the type of transferred substrate to which the laminate is transferred. . For example, a common thermoplastic resin used for transfer foil can be used. Further, the thermoplastic resin may be a resin which is heated, melted or softened to develop tackiness or adhesiveness, and a curable resin which partially cures may be used. Specifically, acrylic resin, urethane resin, amide resin, epoxy resin, styrene-butadiene copolymer, natural rubber, casein, gelatin, rosin resin, terpene resin, phenol resin, styrene resin, silicone resin, styrene resin, polyolefin Those known as conventional adhesives such as urethane resin, ionomer resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, polyester resin, and polyamide resin can be widely used. The thermoplastic resin may be used alone or in combination of two or more.

  The photosensitive resin whose adhesiveness or adhesiveness is reduced by light irradiation is, for example, one which is cured by irradiation of light of a specific wavelength such as ultraviolet light, visible light, infrared radiation and the like, and the adhesiveness or adhesion is reduced, In a light non-irradiated part, what can adhere | attach a porous conductive layer and a to-be-transferred base material can be used. Specifically, widely known products such as photocurable varnishes in which a photopolymerization initiator is formulated in a polyfunctional (meth) acrylic resin, or photoacid generators or photobase generators in an epoxy resin are widely used. it can. Further, a solvent dilution type, a W / O emulsion type, or a non-solvent type containing no solvent may be used. Such photosensitive resins may be used alone or in combination of two or more.

  In addition to the thermoplastic resin or photosensitive resin, the adhesive layer may contain an additive. In the case of a thermoplastic resin, examples of additives include dispersants, fillers, plasticizers, antistatic agents and the like.

  When a thermoplastic resin is used, the adhesive layer 4 may be formed on the entire surface of the substrate 2 as illustrated in FIG. 1, and a pattern is formed on the substrate 2 as illustrated in FIG. 5A. It may be formed in As shown to Fig.5 (a), when the contact bonding layer 4 is formed in pattern shape on the base material 2, even if it does not partially transfer the laminated body 1, as shown to FIG.5 (c). The pattern of the porous conductive layer 3 can be transferred onto the transferred substrate 11.

Moreover, when using photosensitive resin from which adhesiveness or adhesiveness falls by light irradiation, the contact bonding layer 4 is normally formed in the whole surface on the base material 2 as illustrated to Fig.6 (a).
FIGS. 6 (a) to 6 (d) are process drawings showing another example of the method for producing a conductive substrate using the laminate of the present invention, and the adhesive layer 4 is reduced in tackiness or adhesiveness by light irradiation. It is an example using a photosensitive resin. First, as shown in FIG. 6A, a laminate 1 in which a porous conductive layer 3 and an adhesive layer 4 are sequentially laminated on a base material 2 is prepared, and light 16 is applied to the adhesive layer 4 through a photomask 15. Is irradiated in a pattern, and the adhesiveness or adhesiveness of the light-irradiated portion of the adhesive layer 4 is reduced to form a low adhesive portion 4 b. Next, as shown to FIG.6 (b)-(c), it arrange | positions so that the contact bonding layer 4 of the laminated body 1 and the to-be-transferred base material 11 may contact, and it closely_contact | adheres. Thereafter, as shown in FIG. 6 (d), the substrate 2 side is peeled off. The adhesive layer 4 has an adhesive portion 4a which is a non-irradiated portion, and a low adhesive portion 4b which is a light irradiated portion and has reduced adhesiveness or adhesiveness, so that the adhesive portion 4a adheres to the transferred substrate 11 Although the property is enhanced, the adhesiveness with the transferred substrate 11 is lowered at the low adhesion portion 4 b. Therefore, when the base 2 side is peeled off, the porous conductive layer 3 and the adhesive layer 4 peel off together with the base 2 at the low adhesion part 4b, and adhere to the substrate 11 to be transferred at the adhesive part 4a. Layer 3 is transferred. Thereby, the electroconductive base material 10 which has a pattern of the contact bonding layer 4 and the porous conductive layer 3 is obtained. Also in this case, the pattern of the porous conductive layer 3 can be transferred onto the transferred substrate 11 without partially transferring the laminate 1.

  The thickness of the adhesive layer is not particularly limited as long as it is a thickness that allows foil breakage when transferring the laminate of the present invention to a transferred substrate, and the transfer method, type of transferred substrate, etc. Is selected appropriately. Specifically, the thickness of the adhesive layer is preferably in the range of 0.1 μm to 50 μm, and more preferably in the range of 1 μm to 25 μm. If the thickness of the adhesive layer is too thin, the adhesion to the transfer substrate may be insufficient. On the other hand, if the thickness is too large, the temperature at which the adhesive layer is heated becomes too high when transferring the laminate of the present invention, which may cause damage to the transferred substrate and the like. Further, for example, when the substrate to be transferred is a paper substrate, the paper substrate may be difficult to transfer depending on the type, but in that case, the thickness of the adhesive layer is compared among the above ranges from the viewpoint of transferability. It is preferable to be thick. Further, in the case of transferring the laminate of the present invention to a substrate to be transferred by integral molding such as injection molding, for example, the thickness of the adhesive layer is preferably relatively large within the above range.

  As a method of forming an adhesive layer, for example, a method of applying a resin composition on a porous conductive layer and drying it may be mentioned. As a coating method of a resin composition, it selects suitably from a general coating method, and can be applied.

Moreover, the non-adhesion layer 5 may be formed in pattern shape on the contact bonding layer 4 so that it may illustrate in FIG.5 (b). Also in this case, the pattern of the porous conductive layer 3 can be transferred onto the transferred substrate 11 as shown in FIG. 5C, without partially transferring the laminate 1.
As a material of a non-adhesion layer, the thermoplastic resin which does not fuse | melt, for example with respect to the temperature which an adhesive layer fuses, a thermosetting resin, a photocurable resin etc. are mentioned.
The thickness of the non-adhesive layer may be any thickness as long as the adhesive layer and the substrate to be transferred can be adhered when the laminate of the present invention is transferred to the substrate to be transferred. It is appropriately selected according to the type of transfer substrate and the like. Specifically, the thickness of the non-adhesive layer is preferably in the range of 100 nm to 3 μm.
As a formation method of a non-adhesion layer, the method of apply | coating a resin composition in pattern shape on an adhesion layer, for example, drying, and hardening as needed is mentioned. As a coating method of a resin composition, it selects suitably from a general coating method, and can be applied.

3. Substrate The substrate used in the present invention is to support the above-mentioned porous conductive layer and adhesive layer.
The substrate is not particularly limited as long as it can form the above-mentioned porous conductive layer, and, for example, an inorganic substrate such as a glass substrate or a ceramic substrate, a metal substrate, a resin substrate, a paper base A material etc. can be used.
Among them, the substrate is preferably a resin substrate. In the present invention, since the metal particles can be sintered at a low temperature to form a porous conductive layer, it is not necessary to use a highly heat resistant substrate with little damage to the substrate, and it is heat resistant. Low base materials can also be used. In particular, it is very useful in that inexpensive general-purpose plastic resin substrates such as polyethylene terephthalate can be used.

  As a resin base material, a general resin base material can be used. Preferred specific examples of the resin substrate include polyimide, polyamide, polyamideimide, polyethylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, polyetheretherketone, polyethersulfone, polycarbonate, polyetherimide, epoxy resin, phenol resin, glass -Resin films such as epoxy resins, polyphenylene ethers, acrylic resins, polyolefins such as polyethylene and polypropylene, polycycloolefins such as polynorbornene, and liquid crystalline polymer compounds. Among them, inexpensive general-purpose plastic resin substrates such as polyethylene terephthalate are preferable.

  The base material may have flexibility or may be rigid, and is appropriately selected depending on the method of transferring the laminate of the present invention to a transfer receiving base material and the like. Among them, the substrate is preferably flexible, and for the reasons described above, it is more preferable that the substrate is a flexible resin substrate.

Moreover, the mold release layer may be formed in the surface of a base material, and the mold release process may be given. This is because peeling between the substrate and the porous conductive layer or the protective layer is facilitated.
Examples of the material of the release layer include fluorine-based release agents, silicone-based release agents, and wax-based release agents. Examples of the method for forming the release layer include a method in which a release agent is applied by an application method such as dip coating, spray coating, roll coating, or the like.
Further, examples of the release treatment include surface treatments such as fluorine treatment and silicone treatment.

  The thickness of the substrate is not particularly limited, but in the case of an inorganic substrate, it is usually about 0.1 mm to 10 mm, preferably in the range of 0.5 mm to 5 mm. On the other hand, in the case of a resin substrate, the thickness of the substrate is usually about 1.0 μm to about 1000 μm. When the thickness of the resin substrate is in the above range, deformation of the substrate is suppressed when forming the porous conductive layer, which is preferable in terms of shape stability of the porous conductive layer to be formed, and winding. It is suitable from the point of flexibility when performing continuous processing.

4. Other Configurations The laminate of the present invention may have other configurations as needed, in addition to the above-mentioned base material, porous conductive layer and adhesive layer. For example, an antistatic layer, a heat-resistant protective layer, an abrasion resistant layer, a slippery layer or the like may be provided on the surface of the base opposite to the surface on which the porous conductive layer is formed. In addition, a protective layer may be formed between the substrate and the porous conductive layer. The protective layer is described below.

(Protective layer)
In the present invention, a protective layer 6 may be formed between the substrate 2 and the porous conductive layer 3 as illustrated in FIG. 7 (a). Since the protective layer 6 becomes the outermost layer of the conductive substrate 10 after the porous conductive layer 3 is transferred from the laminate 1 to the transferred substrate 11 as shown in FIG. The porous conductive layer 3 can be protected from abrasion, light, chemicals and the like. In addition, the porous conductive layer can be insulated by providing the insulating protective layer.

As a material of a protective layer, a porous conductive layer can be protected and what is necessary is just to have insulation, for example, an ultraviolet curable resin, electron beam curable resin, etc. are mentioned. The protective layer may further contain a filler.
In addition, a protective film may be used as the protective layer.

As a formation method of a protective layer, the method of apply | coating and drying curable resin composition on a base material is mentioned, for example. Examples of the method for applying the curable resin composition include gravure coating, roll coating, comma coating, gravure printing, screen printing, and gravure reverse roll coating.
When using a protective film as a protective layer, a base material and a protective film can be bonded together via a weak adhesion layer. When the weak adhesive layer peels the substrate, it is preferable that the weak adhesive layer can be peeled together with the substrate.

  The thickness of the protective layer is preferably in the range of 0.5 μm to 30 μm, and more preferably in the range of 3 μm to 15 μm. When the thickness of the protective layer is in the above range, surface physical properties such as excellent high hardness, scratch resistance, chemical resistance and stain resistance can be obtained, and further excellent formability and shape following property can be obtained. it can.

5. The laminate of the present invention can be used for producing a conductive substrate as described later, and for example, printed wiring boards, electromagnetic wave shielding materials, antennas, power semiconductors, noise filters, capacitor electrodes, electrodes for various sensors ( Touch sensors, biosensors, temperature sensors, gas sensors, light sensors, pressure sensors, flow sensors), electrodes for displays, electrodes for solar cells, IC cards, RFIDs etc., and used for bonding materials and connector materials it can.
Further, the laminate of the present invention can be used as an electromagnetic wave shielding layer for preventing unauthorized reading of information recorded on a noncontact IC card, and a conductive layer for modulating a resonance frequency. For example, it is possible to apply a porous conductive layer to a part of the card and transport it as unreadable, and to scratch and remove the entire adhesive layer at the time of use. Since the laminate of the present invention has a porous conductive layer, it can be easily peeled off by scratching by controlling the adhesion of the adhesive layer.
The laminate of the present invention can also be used to form designs, designs, and the like that make use of the color and gloss of the porous conductive layer.

B. Method of Producing Conductive Substrate The method of producing a conductive substrate of the present invention has two embodiments. The embodiments will be separately described below.

1. First Embodiment A method for producing a conductive substrate according to the present embodiment includes a preparation step of preparing the above-mentioned laminate, and a transfer step of transferring the adhesive layer and the porous conductive layer of the above-mentioned laminate onto a transferred substrate. And a manufacturing method characterized by

  Fig.2 (a)-(c) and FIG.3 (a)-(c) are process drawings which show an example of the manufacturing method of the electroconductive base material of this embodiment. In addition, about FIG. 2 (a)-(c) and FIG. 3 (a)-(c), since it described in said "A. laminated body" in detail, description here is abbreviate | omitted.

  In this embodiment, the component derived from the adhesive layer, for example, the resin contained in the adhesive layer can be inserted into the pores of the porous conductive layer, and apparently the components derived from the porous conductive layer and the adhesive layer By becoming a mixture, thermal diffusion can be made less likely to occur. Therefore, in the transfer step, since heat is difficult to escape, it is not necessary to heat excessively, which is advantageous for thermal transfer.

  Further, in the present embodiment, as described above, the component derived from the adhesive layer can be introduced into the pores of the porous conductive layer, and the adhesion between the porous conductive layer and the adhesive layer can be enhanced. Therefore, in the transfer step, the adhesive layer and the porous conductive layer can be well transferred onto the transfer substrate, and excellent transferability can be obtained.

  In the present embodiment, as described above, since the resin contained in the adhesive layer can be introduced into the pores of the porous conductive layer, in the transfer step, the resin containing the porous conductive layer in the adhesive layer And the oxidation of the porous conductive layer can be suppressed. Accordingly, the decrease in conductivity of the porous conductive layer in the transfer step can be suppressed.

  Further, in the present embodiment, since the laminate has the porous conductive layer, the foil breakage property is good, and the adhesive layer and the porous conductive layer of the laminate can be transferred well onto the transferred substrate. . Furthermore, as illustrated in FIGS. 3 (a) to 3 (c), when the pattern of the adhesive layer and the porous conductive layer of the laminate is transferred onto the transfer receiving substrate, it can be transferred with high resolution.

  Moreover, in order to transfer an adhesive layer and a porous conductive layer on a to-be-transferred base material, the base material to which it was difficult to form a porous conductive layer conventionally can also be used as a to-be-transferred base material. Therefore, it is possible to obtain an inexpensive general-purpose plastic resin substrate such as polyethylene terephthalate or a conductive substrate in which a porous conductive layer is formed on a transferred substrate such as a paper substrate. Furthermore, it is also possible to form a porous conductive layer on a three-dimensional object to be transferred. In addition, the conductive substrate can be easily produced only by transferring the adhesive layer and the porous conductive layer onto the transferred substrate.

  Further, in the present embodiment, since the metal particles can be sintered at low temperature to form the porous conductive layer, it is not necessary to use a highly heat resistant base material as the base material of the laminate, and it is heat resistant. Lower substrates can also be used. In particular, inexpensive general-purpose plastic resin substrates such as polyethylene terephthalate can be used. Therefore, the manufacturing cost can be reduced.

  Hereafter, each process in the manufacturing method of the electroconductive base material of this embodiment is demonstrated.

(1) Preparation process The preparation process in this embodiment is a process of preparing the above-mentioned laminated body.
In addition, about a laminated body, since it described in said "A. laminated body" in detail, description here is abbreviate | omitted.

(2) Transfer Step The transfer step in the present embodiment is a step of transferring the adhesive layer and the porous conductive layer of the above-mentioned laminate onto the transferred substrate.

  The substrate to be transferred is not particularly limited as long as the porous conductive layer can be transferred through the adhesive layer, and may be appropriately selected depending on the use of the conductive substrate and the like. For example, a resin base material, a paper base material, a glass base material, a metal base material etc. are mentioned.

  The method for transferring the adhesive layer and the porous conductive layer of the laminate onto the substrate to be transferred is particularly limited as long as the adhesive layer can be adhered to a predetermined position on the substrate to be transferred Instead, it is appropriately selected according to the material of the adhesive layer.

When a thermoplastic resin is used, examples of the heat transfer method include a method using a heating roller or a hot stamp, a method of heat pressing, and the like.
Moreover, as a thermal transfer method, the method of using a shaping | molding die which is illustrated to FIG. 8 (a)-(d) is also mentioned. In the manufacturing method of the electroconductive base material shown to FIG. 8 (a)-(d), the laminated body 1 as shown to Fig.8 (a) is first prepared. In addition, the laminated body 1 is the same as that of the laminated body 1 shown in FIG. Next, as shown in FIG. 8A, the adhesive layer 4 of the laminate 1 and the transfer receiving substrate 11 are laminated so that the laminate 1 and the transfer receiving substrate 11 can be made into the base of the laminate 1. The material 2 is placed in a mold having the upper die 23 and the lower die 24 so that the material 2 faces the upper die 23 and the transfer substrate 11 faces the lower die 24. Subsequently, as shown in FIG. 8 (b), the mold is clamped while heating to mold the laminate 1 and the transferred substrate 11, and at the same time, the laminate 1 is thermally transferred onto the transferred substrate 11. . Thereby, the to-be-transferred base material 11 and the laminated body 1 are integrated. Next, as shown in FIG. 8 (c), the integrated laminate 1 and the transferred substrate 11 are taken out of the mold, and as shown in FIG. 8 (d), the substrate 2 is peeled from the laminate 1 Do. Thereby, the electroconductive base material 10 by which the contact bonding layer 4 and the porous conductive layer 3 were laminated | stacked in order on the to-be-transferred base material 11 is obtained.

  Further, in the case of using a thermoplastic resin, as illustrated in FIGS. 3A to 3C, in the case of thermally transferring the pattern of the adhesive layer and the porous conductive layer onto the transferred substrate, as a thermal transfer method For example, a method using a laser beam or a thermal head can be mentioned.

Moreover, when using photosensitive resin in which adhesiveness or adhesiveness falls by light irradiation, light is irradiated to the adhesive layer of a laminated body in pattern shape, for example, a laminated body and a to-be-transferred base material are stuck, The method of peeling is mentioned. For example, a transfer method as shown in FIGS. 6 (a) to 6 (d) can be applied. In this case, the pattern of the adhesive layer and the porous conductive layer can be transferred onto the transferred substrate. In addition, about the manufacturing method of the electroconductive base material shown to FIG. 6 (a)-(d), since it described in said "A. laminated body", description here is abbreviate | omitted.
Examples of a method of irradiating the adhesive layer with light in a pattern include a method of using a photomask, a method of drawing light using a laser, and the like.
The light to be applied to the adhesive layer is not particularly limited as long as it can reduce the adhesiveness or adhesiveness of the adhesive layer, and is appropriately selected according to the type of photosensitive resin. For example, ultraviolet light, visible light, infrared light and the like can be used.
Examples of the method for bringing the laminate and the transferred substrate into close contact with each other include a method of applying pressure, a method of applying pressure while heating, and the like.

  When the adhesive layer and the porous conductive layer are transferred onto the transferred substrate, the pattern of the adhesive layer and the porous conductive layer may be transferred onto the transferred substrate. A conductive substrate in which a pattern of a porous conductive layer is formed on a transferred substrate can be obtained.

In the case of using a thermoplastic resin, in the case of thermally transferring the pattern of the adhesive layer and the porous conductive layer onto the substrate to be transferred, the method of using a laser beam or a thermal head may be applied as described above. 5 (a) may use the laminated body 1 in which the adhesive layer 4 was previously formed in pattern shape, and the non-adhesive layer 5 has a pattern on the adhesive layer 4 as illustrated in FIG. 5 (b). The laminated body 1 formed in a shape may be used.
In addition, when the pattern of the porous conductive layer is thermally transferred onto the substrate to be transferred, in addition to the above, the porous conductive layer 3 as illustrated in FIG. 4A is formed in advance in a pattern. The laminate 1 may be used.

  Further, in the case of a method using a mold as exemplified in FIGS. 8A to 8D, when the laminate and the transferred substrate are arranged in the mold, the laminate and the transferred base are formed on the mold. The material may be vacuum suctioned so that the laminate and the transferred substrate conform to the shape of the mold, and after laminating the laminate and the transferred substrate, it is heated and molded in a softened state It may be sandwiched by a mold.

After bonding the adhesive layer of the laminate on the substrate to be transferred, the area of the adhesive substrate on the substrate to be transferred is usually porous by physically separating the laminate from the substrate side. The substrate can be peeled off from the conductive layer.
In the case of a method using a mold as illustrated in FIGS. 8 (a) to 8 (d), in the case of a single-wafer laminate, a molded article in which the laminate and the transferred substrate are integrated is obtained. After removal from the mold, the base material of the laminate is peeled off from the molded article. Moreover, in the case of a long laminate, when the molded product in which the laminate and the transferred substrate are integrated is taken out from the mold, the substrate peels from the laminate.

2. Second Embodiment The method for producing a conductive substrate according to the present embodiment includes a preparation step of preparing the above-mentioned laminate, and placing the above-mentioned laminate on a mold, and melting resin for a transfer base material in the mold. And solidifying to form a substrate to be transferred, and at the same time forming and transferring the laminate to the substrate to be transferred, and a peeling step of peeling the substrate of the laminate. Manufacturing method characterized by

The method of manufacturing the conductive substrate of the present embodiment will be described with reference to the drawings.
Fig.9 (a)-(d) is process drawing which shows an example of the manufacturing method of the electroconductive base material of this embodiment. First, a laminate 1 as shown in FIG. 9A is prepared. In addition, the laminated body 1 is the same as that of the laminated body 1 shown in FIG. Next, as shown in FIG. 9A, the laminate 1 is placed in a mold having the fixed mold 21 and the movable mold 22 so that the base material 2 faces the fixed mold 21. Subsequently, as shown in FIG. 9B, the mold is clamped, the molten resin 11a for transferred substrate is injected into the mold, cooled and solidified to simultaneously mold the transferred substrate. Then, the laminate 1 is transferred to the transfer substrate. Thereby, the base material which is a resin molding, and the layered product 1 are laminated and integrated. Next, as shown in FIG. 9 (c), the integrated laminate 1 and the transferred substrate 11 are taken out of the mold, and as shown in FIG. 9 (d), the substrate 2 is peeled from the laminate 1 Do. Thereby, the electroconductive base material 10 by which the contact bonding layer 4 and the porous conductive layer 3 were laminated | stacked in order on the to-be-transferred base material 11 is obtained.

  In this embodiment, the component derived from the adhesive layer, for example, the resin contained in the adhesive layer can be inserted into the pores of the porous conductive layer, and apparently the components derived from the porous conductive layer and the adhesive layer By becoming a mixture, thermal diffusion can be made less likely to occur. Therefore, in the molding and transfer process, heat is less likely to escape, so it is not necessary to heat excessively, which is advantageous for transfer.

  Further, in the present embodiment, as described above, the component derived from the adhesive layer can be introduced into the pores of the porous conductive layer, and the adhesion between the porous conductive layer and the adhesive layer can be enhanced. Therefore, in the molding and transfer step, the adhesive layer and the porous conductive layer can be well transferred onto the transfer substrate, and excellent transferability can be obtained.

  In the present embodiment, as described above, since the resin contained in the adhesive layer can be introduced into the pores of the porous conductive layer, the porous conductive layer is included in the adhesive layer in the molding and transfer steps. And the oxidation of the porous conductive layer can be suppressed. Therefore, the decrease in conductivity of the porous conductive layer in the molding and transfer steps can be suppressed.

  Moreover, in this embodiment, since the base material which is a resin molding and the laminate are laminated and integrated, it is possible to form a porous conductive layer on the base material which is a three-dimensional object.

  Further, in the present embodiment, the laminate has the porous conductive layer, so that the foil-breakability and the resolution are good. Therefore, for example, when using the laminate 1 as shown in FIGS. 5 (a) and 5 (b), transfer can be performed with good foil breakage and high resolution.

  Further, in the present embodiment, since the metal particles can be sintered at low temperature to form the porous conductive layer, it is not necessary to use a highly heat resistant base material as the base material of the laminate, and it is heat resistant. Lower substrates can also be used. In particular, inexpensive general-purpose plastic resin substrates such as polyethylene terephthalate can be used. Therefore, the manufacturing cost can be reduced.

  Hereafter, each process in the manufacturing method of the electroconductive base material of this embodiment is demonstrated.

(1) Preparation process The preparation process in this embodiment is a process of preparing the above-mentioned laminated body.
In addition, about a laminated body, since it described in said "A. laminated body" in detail, description here is abbreviate | omitted.
In the present embodiment, a thermoplastic resin is used as the material of the adhesive layer.

(2) Molding and Transfer Step In the molding and transfer step in this embodiment, the laminate is placed in a mold, and the molten resin for transferred substrate is injected into the mold and solidified to form a transferred substrate. It is the process of transferring the above-mentioned layered product to the above-mentioned receiving base material simultaneously with molding a material.

  When the laminate is disposed in the mold, the laminate is disposed such that the adhesive layer contacts the molten resin for transfer substrate when the molten resin for transfer substrate is injected into the mold. At this time, a stack of sheets may be disposed in the mold, or a predetermined region of the long stack may be intermittently inserted.

When arranging a layered product to a forming die, it may heat and may make a layered product contact with a forming die. At this time, the mold may be heated, and the laminated body may be vacuum suctioned and adhered to the mold, or the laminated body may be heated to perform preforming so that the laminated body conforms to the shape of the mold. The laminate may be adhered to the
In the latter case, the heating temperature is preferably equal to or higher than the glass transition temperature of the base material of the laminate and lower than the melting temperature or the melting point, and more preferably to a temperature near the glass transition temperature of the base material. In addition, glass transition temperature vicinity means the range of glass transition temperature +/- 5 degreeC.

  As the molten resin for a substrate to be transferred, an injection-moldable thermoplastic resin and a thermosetting resin can be used. The thermosetting resin includes a two-component curable resin. The molten resin for transfer base material may be used alone or in combination of two or more.

When the molten resin for transfer base material is a thermoplastic resin, the thermoplastic resin is injected in a fluid state by heating and melting, and is cooled and solidified. When the molten resin for transfer base material is a thermosetting resin, the uncured resin composition is appropriately heated, injected in a fluid state, and heated and solidified. Thereby, it integrates with the to-be-transferred base material with which the laminated body was shape | molded.
Although the heating temperature of the molten resin for transfer base materials changes according to the kind of molten resin for transfer base materials, it is about 80 degreeC-280 degreeC, for example.

  When the laminate is transferred to the transfer substrate, the pattern of the adhesive layer and the porous conductive layer may be transferred to the transfer substrate. A conductive substrate in which a pattern of a porous conductive layer is formed on a transferred substrate can be obtained.

In the case of transferring the pattern of the adhesive layer and the porous conductive layer to the substrate to be transferred, the laminate 1 in which the adhesive layer 4 as illustrated in FIG. 5A is formed in advance in a pattern may be used. Alternatively, a laminate 1 in which the non-adhesive layer 5 is formed in a pattern on the adhesive layer 4 as illustrated in FIG. 5 (b) may be used.
Moreover, when transferring the pattern of a porous conductive layer to a to-be-transferred base material, it laminates | stacks in which the porous conductive layer 3 as illustrated to Fig.4 (a) was formed in pattern shape beforehand besides the above. Body 1 may be used.

  After the molten resin for transfer base material is solidified, a molded article in which the laminate and the formed transfer base material are integrated is taken out from the mold.

(3) Peeling process The peeling process in this embodiment is a process of peeling the base material of the said laminated body.
In the case of a single-wafer laminate, after the molded article in which the laminate and the molded transferred base material are integrated is taken out from the mold, the base material of the laminate is peeled off from the molded article. Moreover, in the case of a long laminate, when the molded product in which the laminate and the molded transferred substrate are integrated is taken out from the mold, the substrate peels from the laminate.
As a result, a conductive substrate in which an adhesive layer and a porous conductive layer are sequentially laminated on a substrate to be transferred which is a resin molded body is obtained.

C. Method of Manufacturing Electronic Device The method of manufacturing an electronic device of the present invention is a manufacturing method characterized by including a conductive substrate manufacturing step of manufacturing a conductive substrate by the above-described method of manufacturing a conductive substrate. .

In the present invention, since the conductive substrate is produced by the method for producing a conductive substrate described above, a porous conductive layer having good conductivity can be formed. Further, for example, in the case of forming a pattern of a porous conductive layer, a pattern of high resolution can be formed.
Further, in the present invention, since the conductive substrate is produced by the method for producing a conductive substrate described above, the production cost can be reduced.

  Hereinafter, steps in the method of manufacturing an electronic device of the present embodiment will be described.

1. Step of Producing Conductive Substrate The step of producing a conductive substrate in the present invention is a step of producing a conductive substrate by the method of producing a conductive substrate described above.
In addition, about the manufacturing method of a conductive base material, since it described in the said "B. manufacturing method of a conductive base material" in detail, description here is abbreviate | omitted.

2. Electronic Device Examples of the electronic device in the present invention include printed wiring boards, electromagnetic wave shielding materials, antennas, power semiconductors, noise filters, capacitor electrodes, electrodes for various sensors (touch sensors, biosensors, temperature sensors, gas sensors, optical sensors) , Pressure sensors, flow sensors), electrodes for displays, electrodes for solar cells, IC cards, RFIDs, bonding materials, connector materials and the like.
When the electronic device of the present invention is, for example, a noncontact IC card, the porous conductive layer is an electromagnetic wave shield layer for preventing unauthorized reading of information recorded on the noncontact IC card, and modulates the resonance frequency. It can be used as a conductive layer for In this case, for example, the card can be temporarily provided with a porous conductive layer, and the adhesive layer can be scratched off later. Since the electronic device of the present invention has a porous conductive layer, it can be easily peeled off by scratching by controlling the adhesion of the adhesive layer.

  The manufacturing method of the electronic device of the present invention may have other processes as needed in addition to the conductive substrate manufacturing process. Other processes are appropriately selected according to the electronic device.

  The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and it has substantially the same configuration as the technical idea described in the claims of the present invention, and any one having the same function and effect can be used. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described in more detail by way of Examples and Comparative Examples.

Synthesis Example 1: Synthesis of Copper Particles
In a 200 ml three-necked flask, 10.0 g of copper hydroxide (manufactured by Wako Pure Chemical Industries, Ltd.), 34.5 g of decanoic acid (Lunac 10-98 manufactured by Kao), and 18.5 g of propylene glycol monomethyl ether (PGME) were weighed. . The mixture was heated to 100 ° C. with stirring and maintained at that temperature for 20 minutes. Thereafter, 41.3 g of 3-ethoxypropylamine (manufactured by Koei Chemical Industry Co., Ltd.) was added, and the mixture was heated and stirred at 100 ° C. for 10 minutes. The mixture is cooled to 10 ° C. using an ice bath, and a solution of 10.0 g of hydrazine monohydrate in 18.5 g of PGME (manufactured by Kanto Chemical Co., Ltd.) is added in the ice bath for 10 minutes. It stirred. The reaction solution was then heated to 100 ° C. and maintained at that temperature for 10 minutes. After cooling to 30 ° C., 66 g of hexane was added. After centrifugation, the supernatant was removed. The precipitate was washed with hexane to obtain copper particles.
When the obtained copper particles were observed by a transmission electron microscope (TEM), the average primary particle size was 65 nm.

Preparation Example 1: Preparation of Copper Particle Dispersion 1
40 parts by mass of the copper particles obtained in Synthesis Example 1, 4 parts by mass of Solsperse 41000 (manufactured by Lubrizol) as a polymer dispersant, and 56 parts by mass of propylene glycol monomethyl ether (PGME) are mixed, and paint shaker (manufactured by Asada Iron Works) The copper particle dispersion 1 was obtained by dispersing in 2 mm zirconia beads for 1 hour as preliminary dispersion and further for 2 hours in 0.1 mm zirconia beads as main dispersion.

[Production Example 1: Production of Conductive Film A]
A copper particle dispersion 1 is coated on a PET film (trade name Cosmo Shine A4100, manufactured by Toyobo Co., Ltd., film thickness 100 μm) using Miyabar # 4, dried at 80 ° C. for 3 minutes with a warm air dryer, I got Thereafter, while introducing hydrogen gas at an introduction pressure of 20 Pa, the porous conductive layer is fired for 240 seconds at a microwave output of 450 W using a microwave surface wave plasma processing apparatus (MSP-1500, manufactured by Micro Electronics Co., Ltd.) Conductive film A conductive film was obtained.

[Production Example 2: Production of Conductive Film B]
A conductive film B having a porous conductive layer was obtained by firing for 120 seconds at a microwave output of 450 W in the same manner as the conductive film A except that the PET film (film thickness 5 μm) was changed.

[Production Example 3: Production of Conductive Film C]
Copper was deposited on a PET film (trade name: Cosmo Shine A4100, manufactured by Toyobo Co., Ltd., film thickness 100 μm) by a sputtering method to obtain a conductive film C having a conductive layer.

[Evaluation]
(Measurement of sheet resistance of conductive layer)
The conductivity evaluation of the conductive layer was performed by measuring a sheet resistance value by a four-point probe method using a surface resistance meter ("Loresta GP" manufactured by Dia Instruments, Inc., PSP type probe). The sheet resistance value of the porous conductive layers of the conductive films A and B was 0.20 Ω / □, and the sheet resistance value of the conductive layer of the conductive film C was 0.075 Ω / □.

(Measurement of film thickness of conductive layer)
The film thickness of the conductive layer was evaluated as follows. Carbon was deposited sequentially by vacuum evaporation method on the top of the conductive layer as a protective layer, and platinum was deposited by sputtering as a protective layer, and then tungsten was deposited using FIB (focused ion beam, FB-2100 manufactured by Hitachi High-Technologies) After that, a cross section of the conductive layer was produced. Thereafter, the cross section of the conductive layer was observed in a state in which the substrate was inclined 45 ° using an SEM (S-4800 manufactured by Hitachi High-Technologies), and the film thickness was measured from the SEM image. The film thickness was measured at 10 locations in the SEM image measured at a magnification of 30 k to 40 k, the inclination was corrected, and the average value was taken as the film thickness. The film thickness of the conductive layer was 400 nm in all of the conductive films A, B, and C. From these results, it was found that the volume resistivity of the conductive films A and B was 8 μΩ · cm, and the volume resistivity of the conductive film C was 3 μΩ · cm.

(Measurement of porosity of conductive layer)
The porosity of the conductive layer was measured as follows. The area of the hole and the area of the conductive layer in the SEM image obtained in the film thickness measurement were respectively calculated, and the area of the hole was divided by the area of the conductive layer to obtain the porosity in the cross section. The porosity of the porous conductive layer of the conductive film A was 35%, and the porosity of the porous conductive layer of the conductive film B was 25%. There were no voids in the conductive layer of the conductive film C.

Example 1
(Formation of adhesive layer)
A coating solution was prepared by adding 30% by mass of methyl isobutyl ketone (MIBK) equivalent to TM-R850 (LV-NT) K3 manufactured by Dainichi Seisei Co., Ltd., which is an adhesive, and sufficiently stirring. The coating solution was applied onto the porous conductive layer of the conductive film A with an applicator of 10 mils, and dried with a hot air dryer at 90 ° C. for 1 minute.

(Transcription)
Next, a laminated film C001 (Sumitomo Chemical made film thickness 125 μm) of polycarbonate (hereinafter abbreviated as PC) and polymethyl methacrylate (hereinafter abbreviated as PMMA) is used as the substrate to be transferred on the PC surface of the substrate to be transferred The adhesive coated surface of the above-mentioned conductive film A was overlapped, and heat lamination was performed at a temperature of 130 ° C., GAP 1 mm or less, at a transfer speed of 0.3 m / min using a multilaminator GL835PRO manufactured by Japan GBC. Thereafter, the PET film was peeled off.
The porous conductive layer was transferred 100% to the transferred substrate, and the sheet resistance after transfer was 0.22 Ω / □.

Example 2
In the formation of the adhesive layer, plus coat PGC10 made by Washin Chemical Co., Ltd. was applied as an adhesive on the porous conductive layer of the conductive film A with an applicator of 10 mils and dried with a warm air dryer at 90 ° C. for 1 minute The adhesive layer was formed and transferred in the same manner as in Example 1 except that the temperature was 130.degree.
The porous conductive layer was transferred 100% to the transferred substrate, and the sheet resistance after transfer was 0.20 Ω / □.

[Example 3]
In the formation of the adhesive layer, Chemipearl S300 manufactured by Mitsui Chemicals, Inc. was applied as an adhesive on the porous conductive layer of the conductive film A with Miyabar # 8 and dried with a hot air dryer at 70 ° C. for 3 minutes, and transfer The adhesive layer was formed and transferred in the same manner as in Example 1 except that a commercially available copy paper was used as a substrate for transfer and the temperature was 100.degree.
The porous conductive layer was transferred 100% to the transferred substrate, and the sheet resistance after transfer was 0.20 Ω / □.

Example 4
In the formation of the adhesive layer, Chemipearl EV210 manufactured by Mitsui Chemicals, Inc. was applied as an adhesive on the porous conductive layer of the conductive film A with Miyabar # 16 and dried with a hot air dryer at 90 ° C. for 3 minutes, and transfer The adhesive layer was formed and transferred in the same manner as in Example 1 except that the temperature was 150.degree.
The porous conductive layer was transferred 100% to the transferred substrate, and the sheet resistance after transfer was 0.20 Ω / □.

[Example 5]
In the formation of the adhesive layer, Bonron XPS-001 manufactured by Mitsui Chemicals, Inc. was applied as an adhesive on the porous conductive layer of the conductive film A with Miyabar # 16 and dried with a hot air dryer at 90 ° C. for 3 minutes, In the transfer, an adhesive layer was formed and transferred in the same manner as in Example 1 except that glossy paper was used as a transfer target substrate and the temperature was 130 ° C.
The porous conductive layer transferred 100% to the transfer substrate, and the sheet resistance after transfer was 0.21 Ω / □.

[Example 6]
In the formation of the adhesive layer, Bonlon XPS-003 manufactured by Mitsui Chemicals, Inc. was applied as an adhesive on the porous conductive layer of the conductive film A with Miyabar # 16 and dried with a warm air dryer at 90 ° C. for 3 minutes, In the transfer, an adhesive layer was formed and transferred in the same manner as in Example 1 except that glossy paper was used as a transfer target substrate and the temperature was 150 ° C.
The porous conductive layer was transferred 100% to the transferred substrate, and the sheet resistance after transfer was 0.20 Ω / □.

[Example 7]
(Formation of adhesive layer)
An adhesive, BCD # 700 clear made by DNP Fine Chemical Co., Ltd., was coated on the porous conductive layer of the conductive film B with Miyabar # 4, and dried at 90 ° C. for 3 minutes with a hot air dryer.

(Transcription)
The conductive film B on which the adhesive layer is formed is set as a transfer ribbon in a thermal head printer (Zebra140Xi4), and a printing test is performed using a gloss coated paper as a transfer target substrate. It formed, and the continuity could also be confirmed by the tester.

Comparative Example 1
When transfer was performed in the same manner as in Example 1 except that the conductive film C was used instead of the conductive film A, no transfer was possible.

Comparative Example 2
When transfer was performed in the same manner as in Example 2 except that the conductive film C was used instead of the conductive film A, no transfer was possible.

Comparative Example 3
When transfer was performed in the same manner as in Example 3 except that the conductive film C was used instead of the conductive film A, no transfer was possible.

Comparative Example 4
When transfer was performed in the same manner as in Example 4 except that the conductive film C was used instead of the conductive film A, no transfer was possible.

Comparative Example 5
The transfer was performed in the same manner as in Example 5 except that the conductive film C was used instead of the conductive film A, but no transfer was possible.

Comparative Example 6
When transfer was performed in the same manner as in Example 6 except that the conductive film C was used instead of the conductive film A, no transfer was possible.

[Production Example 4: Production of Conductive Film D]
After diluting nano Ag ink (made by 3 stars belt product name MDot CF107) with pentanediol 40%, it is applied to PET film (trade name Cosmo Shine A4100, Toyobo, film thickness 100 μm) using Miyabar # 4 and warm air Drying at 120 ° C. for 30 minutes in a drier and baking were performed to obtain a conductive film D having a silver gloss and a porous conductive layer.
The film thickness of the porous conductive layer of the conductive film D was 380 nm, the sheet resistance value was 0.20 Ω / □, and the porosity was 30%.

[Example 8]
In the formation of the adhesive layer, Chemipearl S300, manufactured by Mitsui Chemicals, Inc., is coated on the porous conductive layer of the conductive film D with Miyabar # 4 as an adhesive and dried with a warm air dryer at 90 ° C. for 3 minutes; The adhesive layer was formed and transferred in the same manner as in Example 1 except that gloss-coated paper was used as a substrate for transfer and the temperature was 130.degree.
The porous conductive layer was transferred 100% to the transferred substrate, and the sheet resistance after transfer was 0.20 Ω / □.

[Example 9]
(Formation of adhesive layer)
A coating solution was prepared by additionally diluting 30% by mass with methyl isobutyl ketone (MIBK) to TM-R850 (LV-NT) K3 manufactured by Dainichi Seisei Co., Ltd., an adhesive. The coating solution was applied onto the porous conductive layer of the conductive film A with an applicator of 10 mils, and dried with a hot air dryer at 90 ° C. for 1 minute.

(Transcription)
The conductive film A having the adhesive layer formed thereon was set in a mold of an in-mold molding machine, and then a mixed resin composed of PC and ABS was melted and flowed on the adhesive coated surface. After cooling, the molded product was taken out and the PET film was peeled off.
The porous conductive layer was transferred 100% to a resin layer composed of a mixed resin of PC and ABS, and the sheet resistance after transfer was 0.22 Ω / □.

1 ... laminate 2 ... substrate 3 ... porous conductive layer 4 ... adhesive layer 6 ... protective layer 10 ... conductive substrate 11 ... transferred substrate

Claims (6)

A substrate,
A porous conductive layer formed on the substrate;
An adhesive layer formed on the porous conductive layer;
The porous conductive layer is a sintered body of metal nanoparticles,
A protective layer is formed between the substrate and the porous conductive layer,
The protective layer has an insulating property, and the porous conductive layer laminate, wherein a layer der Rukoto to protect after the transfer.   The laminate according to claim 1, wherein the substrate is a resin substrate. A preparation step of preparing a laminate according to claim 1 or 2 ;
And a transfer step of transferring the adhesive layer and the porous conductive layer of the laminate onto a substrate to be transferred. The method for producing a conductive substrate according to claim 3, wherein in the transfer step, the pattern of the adhesive layer, the porous conductive layer , and the protective layer of the laminate is transferred onto the transferred substrate. . It has a base material, the porous conductive layer formed on the above-mentioned base material, and the adhesion layer formed on the above-mentioned porous conductive layer, and the above-mentioned porous conductive layer is a sintered compact of metal nanoparticles. Preparing a laminate , and
The laminate is disposed in a mold, and the molten resin for transfer base material is injected into the mold and solidified to mold the transfer base material, and at the same time transfer the laminate to the transfer base material. Molding and transfer steps,
And a peeling step of peeling the base material of the laminate. A method for producing an electronic device, comprising the step of producing a conductive substrate by the method for producing a conductive substrate according to any one of claims 3 to 5 , wherein the conductive substrate is produced.

Images