JP2016132127A - Laminate, production method of conductive substrate using the same, and production method of electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate capable of transferring a porous conductive layer excellent in foil breakage resistance and transferability, and having excellent conductivity; and to provide a production method of a conductive substrate using the same, and a production method of an electronic device.SOLUTION: There is provided a laminate having a substrate, a porous conductive layer formed on the substrate, and an adhesion layer formed on the porous conductive layer.SELECTED DRAWING: Figure 1

Description

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

  Conventionally, as a method for forming a metal layer as a conductive layer or a decorative 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 for forming an antenna terminal portion using a metal vapor-deposited layer transfer sheet in which a protective layer, a metal vapor-deposited layer and an adhesive layer are laminated on a substrate. In the case of a metal vapor deposition layer like patent document 1, heat resistance is calculated | required by the base layer of a metal vapor deposition layer. Therefore, when an inexpensive general-purpose plastic film such as a PET film is used as a base material, there is a problem that the film forming process, metal type, film thickness, etc. are limited because of low heat resistance, and a protective layer is formed on the base material. The heat resistance is ensured by forming etc. On the other hand, a substrate having high heat resistance such as a polyimide film, a PEN film, or a glass film can be used as the substrate, but these substrates are expensive and suitable for the substrate of the transfer sheet to be peeled and removed. I can't say.

  Patent Document 2 includes a release sheet that is a base material, an insulator layer provided on the release sheet, and a metal foil disposed in contact with the insulator layer, and the metal foil is disposed on the release sheet. There has been proposed a metal foil sheet for transfer that is adhered by electrostatic attraction generated between the insulating layer and the insulator layer. In the case of the metal foil as in Patent Document 2, there is a problem that the adhesion to the substrate is low, and the adhesion is ensured by forming a resin layer such as an insulator layer on the substrate.

  Patent Document 3 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 coated on the metal foil. Manufacture of a metal foil fuse that uses a transfer mold having a convex fuse element pattern to transfer a metal foil onto an insulating substrate via a thermosetting adhesive to the pattern shape of the fuse element of the transfer mold A law has been proposed. Also in this case, the adhesion of the resin film and the metal foil is ensured by providing the metal foil on the surface of the resin film via an adhesive.

  By the way, a transfer sheet is required to have a foil cutting property. However, since the metal vapor-deposited layer and the metal foil are ductile, there is a problem that burrs are generated during transfer and the foil breakability is poor. Moreover, in a metal vapor deposition layer, a crystal grain may grow large, In that case, of course, foil cutting property worsens. In addition, in order to improve the foil cutting property, a method has also been proposed in which a transfer sheet is sandwiched between rugged molds, and the transfer is performed after applying stress, but the process becomes complicated.

  In general, since metal has a high thermal conductivity, heat tends to diffuse in a metal vapor deposition layer or a metal foil, and energy required for transfer tends to increase, and the shape of the transfer sheet may be distorted.

  In addition, when transferring a transfer sheet to a transfer object, for example, when a heat sealant such as a thermoplastic resin is used as an adhesive layer in order to adhere the metal vapor deposition layer or metal foil to the transfer object, thermoplasticity Heat above the glass transition temperature of the resin. At this time, thermal transfer is realized by the fact that the adhesion force between the transfer target and the metal vapor deposition layer or the metal foil is larger than the adhesion force between the substrate and the metal vapor deposition layer or the metal foil. In this case, since there is a limit to adjusting the above adhesion force only with the heat sealant, the adhesion force between the transfer target and the metal vapor deposition layer or the metal foil is determined based on the adhesion between the substrate and the metal vapor deposition layer or the metal foil. In order to make it larger than the force, it has been proposed to form fine irregularities such as roughening the contact surface with the metal vapor deposition layer or the metal foil adhesive layer, but the process becomes complicated.

  In Patent Document 4, a donor element in which a light absorption layer and a metal nanoparticle layer are laminated on a donor substrate as a base material is used, the donor element and the receiving substrate are arranged in contact with each other, and laser is irradiated from the donor element side. Then, a method of forming an electric conductor pattern on a receiving substrate by annealing and transferring the metal nanoparticle layer has been proposed. However, in this method, since metal nanoparticles are used as the conductive material, the electrical resistance at the interface between the particles is a problem. To achieve the desired conductivity, it is necessary to anneal the metal nanoparticles at a high temperature. is necessary. Therefore, the base material needs to withstand the high heat of laser annealing, the base material is limited, and it is difficult to use an inexpensive general-purpose plastic film. Moreover, an expensive base material with high heat resistance must be used as the base material to be peeled and removed, resulting in high cost.

On the other hand, in Patent Document 5, a transfer sheet in which a sintered body layer of metal ultrafine particles is formed on a base material is used, and a metal ultrafine particle is sintered on a transfer substrate having an adhesive layer formed on the surface. There has been proposed a method for forming a wiring pattern made of a binder layer. In this method, by using metal ultrafine particles, sintering can be performed even at a relatively low temperature.
However, the ultrafine metal particles may be oxidized to lower the conductivity, and the conductivity may be lowered when the sintered body of the ultrafine metal particles is transferred to the substrate to be transferred.

JP 2007-324641 A Japanese Unexamined Patent Publication No. 7-101198 JP-A-5-314888 JP-T 2008-554181 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 having excellent foil cutting property and transferability and good conductivity, and a conductive substrate using the laminate. It is a main object of the present invention to provide a manufacturing method and an electronic device manufacturing method.

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

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. Therefore, thermal diffusion can be made difficult to occur, which is advantageous for thermal transfer. In addition, the adhesion between the porous conductive layer and the adhesive layer can be improved, and excellent transferability can be obtained. Furthermore, the porous conductive layer can be protected with 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.
Moreover, in this invention, since it has a porous conductive layer, brittleness is provided and favorable foil tearability and resolution can be obtained. In addition, since the porous conductive layer can be formed by sintering metal particles at a low temperature, the substrate is less likely to be damaged, and it is not necessary to use a substrate having high heat resistance. Materials can also be used.
Moreover, an electroconductive base material can be easily produced by using the laminated body of this invention.

  Moreover, in this invention, it is preferable that the said base material is a resin base material. As described above, in the present invention, a substrate having low heat resistance can be used, which 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 substrate and the porous conductive layer. After the transfer, the porous conductive layer can be protected by the protective layer. Moreover, a porous conductive layer can be insulated by setting it as the protective layer which has insulation.

  The present invention also includes a preparation step for preparing the above-described laminate, and a transfer step for transferring the adhesive layer and the porous conductive layer of the laminate onto the substrate to be transferred. A manufacturing method is provided.

  In this invention, since the above-mentioned laminated body is used, it is excellent in foil cutting property, resolution, and transferability. Moreover, a porous conductive layer having good conductivity can be obtained even after transfer. Furthermore, an electroconductive base material can be produced easily.

  In the said invention, you may transcribe | transfer the pattern of the contact bonding layer and porous conductive layer of the said laminated body on the said to-be-transferred base material at the said transfer process. A conductive substrate in which a pattern of a porous conductive layer is formed on a transfer substrate can be obtained.

  The present invention also provides a preparation step for preparing the above-described laminate, and the laminate is placed in a mold, and a molten resin for a transfer substrate is injected into the mold and solidified to be transferred. A method for producing a conductive substrate, comprising: forming and transferring the laminate to the substrate to be transferred; and a peeling step for peeling the substrate of the laminate. provide.

  In this invention, since the above-mentioned laminated body is used, it is excellent in foil cutting property and transferability. Moreover, a porous conductive layer having good conductivity can be obtained even after transfer. Furthermore, a three-dimensional conductive substrate can be easily produced.

  Furthermore, this invention provides the manufacturing method of the electronic device characterized by having the electroconductive base material preparation process which produces an electroconductive base material with the manufacturing method of the above-mentioned electroconductive base material.

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

  The laminate of the present invention is excellent in foil breakability and transferability, and has the effect of being able to transfer a porous conductive layer having 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 other example of the laminated body of this invention, and an electroconductive base material. It is a schematic sectional drawing which shows the other example of the laminated body of this invention, and an electroconductive 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 other example of the laminated body of this invention, and an electroconductive 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 of the present invention, the method for producing a conductive substrate, and the method for producing an electronic device will be described in detail.

A. Laminated body The laminated body of this invention has a base material, the porous conductive layer formed on the said base material, and the contact bonding layer formed on the said porous conductive layer, It is characterized by the above-mentioned. .

The laminated body of this invention is demonstrated with reference to 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 material 2, a porous conductive layer 3 formed on the base material 2, and an adhesive layer 4 formed on the porous conductive layer 3. Yes.

  2A to 2C are process diagrams showing an example of a method for producing a conductive substrate using the laminate of the present invention, and an example using the laminate shown in FIG. First, as shown in FIG. 2A, the laminate 1 and the substrate to be transferred 11 are prepared. Next, as shown in FIG. 2B, the laminate 1 is disposed so that the adhesive layer 4 of the laminate 1 and the transfer substrate 11 are in contact with each other, and thermocompression bonding is performed from the laminate 1 side. Then, as shown in FIG.2 (c), the base material 2 is peeled. As a result, the adhesive layer 4 and the porous conductive layer 3 are transferred to the transfer substrate 11 in the thermocompression-bonded region, and the conductive substrate 10 is obtained.

  3A to 3C are process diagrams showing another example of a method for producing a conductive substrate using the laminate of the present invention, and an example using the laminate shown in FIG. First, as shown in FIG. 3A, the laminate 1 and the substrate to be transferred 11 are prepared. Next, as shown in FIG. 3B, the laminate 1 is disposed so that the adhesive layer 4 of the laminate 1 and the substrate 11 to be transferred are in contact with each other, and thermocompression bonding is performed from the laminate 1 side. At this time, partial thermal compression bonding is performed by the thermal head 12 of the thermal head printer. Then, as shown in FIG.3 (c), the base material 2 side is peeled. As a result, the adhesive layer 4 and the porous conductive layer 3 are transferred to the transfer substrate 11 in the thermocompression-bonded region, 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 apparently a mixture of the component derived from the porous conductive layer and the adhesive layer. As a result, thermal diffusion can be made difficult to occur. Therefore, when transferring the laminate of the present invention to a substrate to be transferred, heat does not easily escape, so there is no need to heat excessively, which is advantageous for thermal 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 in contact with the porous conductive layer and the adhesive layer is increased. The adhesion between 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 the substrate to be transferred, the adhesive layer and the porous conductive layer can be satisfactorily transferred to the substrate to be transferred, and excellent transferability can be obtained.

  As will be described later, in the porous conductive layer, the metal particles are sintered and fused together, so that the region where the component derived from the adhesive layer enters the pores of the porous conductive layer is also conductive. Contribute to. Therefore, the adhesiveness with the adhesive layer can be improved without reducing the conductivity.

  In addition, the conductivity of conductive materials such as metals and metal oxides may decrease due to 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. May decrease. On the other hand, in the present invention, as described above, since the resin contained in the adhesive layer can enter the pores of the porous conductive layer, the laminate of the present invention is transferred to the substrate to be transferred. In this case, the porous conductive layer can be protected with the resin contained in the adhesive layer, and oxidation of the porous conductive layer can be suppressed. Accordingly, it is possible to suppress a decrease in conductivity of the porous conductive layer during transfer.

  In the present invention, since the porous conductive layer is porous, brittleness is imparted. Therefore, unlike conventional vapor deposition layers, burrs are hardly generated during transfer, and large crystal grains are not included. Therefore, good foil breakability can be obtained. Furthermore, as illustrated in FIGS. 3A to 3C, when the pattern of the adhesive layer and the porous conductive layer of the laminate of the present invention is transferred to a substrate to be transferred, it can be transferred with high resolution. it can.

  Here, it is known that metal particles are sintered at a low temperature when the particle diameter is reduced. In the present invention, when such metal particles become nanoparticles, the porous conductive layer is formed by sintering the metal particles at a low temperature by utilizing the property of sintering at a temperature much lower than the melting point of the metal particles. Can be formed. Therefore, there is little damage to the substrate, and it is not necessary to use a substrate having high heat resistance, and a substrate having low heat resistance can also be used. In particular, it is very useful in that an inexpensive general-purpose plastic resin substrate such as polyethylene terephthalate can be used.

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

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

  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 holes, and has a surface area larger than that of a conductive layer having the same volume and having no holes.

Examples of the conductive material constituting the porous conductive layer include metals and metal oxides. The conductive material constituting the porous conductive layer may be one type or two or more types.
Of these, metals are preferred. This is because the metal particles can be sintered at a lower temperature 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, and lead. Among these, silver and copper are preferable from the viewpoint of conductivity and cost. 1 type may be sufficient as a metal and 2 or more types may be sufficient as it.
Examples of the metal oxide include indium tin oxide and antimony-doped tin oxide.

  The shape of the hole in the porous conductive layer is not particularly limited as long as the component derived from the adhesive layer can enter at least a part of the holes. It is preferable that at least the surface on the adhesive layer side of the porous conductive layer has communication holes 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 the conductivity and adhesiveness can be adjusted as appropriate. 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 in the range of 15% to 40%. It is preferable to be within. If the porosity is too large, the adhesion between the porous conductive layer and the substrate may be reduced. On the other hand, if the porosity is too small, the above-described effects due to the components derived from the adhesive layer entering the pores of the porous conductive layer may not be sufficiently obtained.
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 a contact bonding layer is mixed is also contained.

The porosity can be confirmed from a scanning electron microscope (SEM) image of a cross section of the porous conductive layer before forming the adhesive layer. Specifically, the area of the pores and the area of the porous conductive layer are calculated from the obtained SEM images, and the porosity in the cross section is obtained by dividing the area of the holes by the area of the porous conductive layer. be able to. 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 in 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, respectively, and the area of the hole and the area of the component derived from the adhesive layer are calculated. The porosity in the cross section can be obtained by dividing the total by the area of the porous conductive layer.
Similarly, the porosity is similarly determined for a plurality of cross sections in accordance with the size of the laminate, 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 dispersant, the firing conditions, and the like in the method for forming 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. Also good. When the porous conductive layer 3 is formed in a pattern on the substrate 2 as shown in FIG. 4A, the laminated body 1 is shown in FIG. As described above, the pattern of the porous conductive layer 3 can be transferred onto the transfer substrate 11.

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

As a method for forming the porous conductive layer, a method in which a metal particle dispersion containing metal particles is applied on a substrate and fired is used.
In the present specification, the metal particles include alloy particles, metal compound particles, and the like in addition to metal particles.

As a metal particle, it can select from the metal particle which produces electroconductivity after baking suitably, and can be used.
Examples of the metal constituting the metal particles include gold, silver, copper, nickel, platinum, palladium, molybdenum, aluminum, antimony, tin, chromium, indium, gallium, germanium, zinc, titanium, lead, and the like. Among these, silver and copper are preferable from the viewpoint of conductivity and cost. The metal constituting the metal particles may be one kind or two or more kinds. Further, a metal in which two or more kinds of metals form a core-shell structure, a metal in which the surface of particles in a metal state is oxidized or nitrided, or the like may be used. The surface of the metal particles may be oxidized or may be oxidized to the inside.
Examples of the metal compound constituting the metal compound particles include metal oxides, metal nitrides, metal hydrides, metal hydroxides, and organometallic compounds. These metal compounds are preferably those which are decomposed into a metal state upon firing. For example, particles of a metal compound that exhibits conductivity by reduction, specifically, particles of a metal compound such as cuprous oxide, cupric oxide, silver oxide, copper nitride, copper hydride, and the like can be given. Examples of the metal oxide include indium tin oxide and antimony-doped tin oxide.
A metal particle may be used individually by 1 type and may be used in combination of 2 or more type.
Among these, particles in a metal state are preferable. This is because the metal particles can be sintered at a lower temperature 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. This is because when a metal particle dispersion containing metal nanoparticles is applied and baked to form a porous conductive layer, the pore size and crystal grain size can be controlled within a range suitable for foil breakability. .

The average particle diameter of the metal particles is preferably in the range of 1 nm to 200 nm, more preferably in the range of 2 nm to 150 nm, and particularly preferably in the range of 2 nm to 100 nm. When the average particle diameter is within 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 kept low, sufficient sintering is possible, and high conductivity is obtained.
Here, the average particle diameter of the metal particles is the average primary particle diameter of the metal particles in the metal particle dispersion, and can be measured from an observation image obtained by a transmission electron microscope.

  As a method for preparing metal particles, for example, a physical method obtained by pulverizing metal powder or metal oxide powder by a mechanochemical method or the like; CVD method, vapor deposition method, sputtering method, thermal plasma method, laser method, etc. A chemical dry method; a method called a chemical wet method using a thermal decomposition method, a chemical reduction method, an electrolysis method, an ultrasonic method, a laser ablation method, a supercritical fluid method, a microwave synthesis method, or the like can be given.

  In order to obtain a metal particle dispersion, the obtained metal particles are obtained by using a protective agent such as a water-soluble polymer compound such as polyvinylpyrrolidone or a graft copolymer polymer compound, a surfactant, a metal or a metal oxide. It is preferable to coat with a compound having a thiol group, amino group, hydroxyl group, or carboxyl group that interacts with the product. Depending on the method of synthesizing the metal particles, the pyrolyzate or oxide of the raw material may protect the particle surface and contribute to dispersibility. In the case of a wet method such as a thermal decomposition method or a chemical reduction method, the reducing agent or the like may act as a protective agent for the metal particles as it is. In addition, in order to improve the dispersion stability of the metal particle dispersion liquid, surface treatment of the metal particles is performed, or a dispersant composed of a polymer compound, an ionic compound, a surfactant or the like is added to the metal particle dispersion liquid. May be.

  The dispersion medium used in the metal particle dispersion is not particularly limited as long as it can disperse metal particles. 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.

  Moreover, you may add a viscosity modifier, a surface tension modifier, a stabilizer, etc. to a metal particle dispersion liquid as needed.

  The metal particle dispersion preferably has a solid content concentration in the range of 5% by mass to 95% by mass, particularly in the range of 10% by mass to 90% by mass, particularly in the range of 15% by mass to 85% by mass. Preferably there is. When the solid content concentration is within the above range, sufficient conductivity is obtained, the viscosity is sufficiently low, and the metal particle dispersion can be easily applied to the substrate.

When applying the metal particle dispersion on 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.
Examples of the method for applying the metal particle dispersion on the substrate include gravure printing, screen printing, spray coating, spin coating, comma coating, bar coating, knife coating, die coating, offset printing, flexographic printing, inkjet printing, and dispenser. Printing etc. can be mentioned. When applying a metal particle dispersion in a pattern on a substrate, gravure printing, flexographic printing, screen printing, and inkjet printing are preferred from the viewpoint that fine patterning can be performed.

  After application of the metal particle dispersion, drying may be performed by a normal method. For example, the drying method which heats for about 0.1 minute-20 minutes at the temperature of about 80 degreeC-140 degreeC using a general oven etc. is mentioned. Although the thickness of the coating film after drying can be controlled by adjusting the coating amount, the average particle diameter of the metal particles, and the like, it is usually about 0.01 μm to 100 μm, preferably 0.1 μm to 50 μm. Within range.

The method for firing the coating film of the metal particle dispersion may be any method that can sinter the metal particles, and a general firing method can be applied. For example, a heat treatment method, a light treatment method, a plasma treatment method, or the like can be given. By baking the coating film, 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, hot pressing using a hot plate or a hot roll.
Examples of the light treatment include laser treatment, ultraviolet lamp treatment, infrared lamp treatment, far-infrared lamp treatment, and flash light lamp treatment.
The plasma treatment is a treatment that ionizes gases such as hydrogen, carbon monoxide, ammonia, alcohol, etc. that exhibit reducibility into a plasma state and generates highly reactive active species, for example, electron cyclotron resonance (ECR) plasma. , Capacitively coupled plasma, inductively coupled plasma, atmospheric pressure plasma, microwave plasma, surface wave plasma generated by application of microwave energy, and the like. Among these, surface wave plasma treatment is preferable.
In addition, said baking method can be used in combination of 2 or more type.

  Microwave surface wave plasma has the characteristics of high plasma density and low electron temperature, and the coating film can be fired at a low temperature in a short time to form a dense and smooth porous conductive layer. Can do. The surface wave plasma is irradiated with plasma having a uniform density within the surface with respect to the processing surface. As a result, compared to other firing methods, it is less likely to form a non-uniform film such as partial sintering of metal particles in the plane, and grain growth can be prevented. A dense and smooth film can be 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, there is little damage to a resin base material, and there is also little damage to another layer.

  Moreover, the microwave surface wave plasma is suitable for enhancing the adhesion of the porous conductive layer to the resin substrate. This is presumably because microwave surface wave plasma is likely to generate a polar functional group such as a hydroxyl group or a carboxyl group at the interface between the substrate and the porous conductive layer. In particular, when a plasma generated in a reducing gas atmosphere is used for a polyester base material, the plasma of the gas containing the reducing gas reacts with the ester bond of the base material, and is modified to the interface side of the base material. It is presumed that the adhesiveness at the interface between the porous conductive layer and the base material is improved because the quality is increased and many reactive groups with high polarity are generated. Therefore, the microwave surface wave plasma is different from the conventional method in which the substrate surface is roughened by plasma treatment or the like in advance and the adhesion to the porous conductive layer is improved. It is excellent in that the adhesion to the layer is high.

  In addition, about the conditions of microwave surface wave plasma, the conditions as described in Unexamined-Japanese-Patent No. 2010-86825 are applicable, for example.

The atmosphere at the time of firing is appropriately selected according to the type of conductive material constituting the porous conductive layer.
In the case of forming a porous conductive layer containing a metal, an atmosphere of an inert gas or a reducing gas is preferable, and a reducing gas is particularly preferable. In the case of a reducing gas atmosphere, the oxide present on the surface of the metal particles is reduced and removed, and a porous conductive layer having good conductivity can be formed. Therefore, when forming a porous conductive layer containing a metal, metal particles whose surface is oxidized or metal particles whose surface is oxidized can be used as the metal particles.

Examples of the reducing gas include hydrogen, carbon monoxide, ammonia, and a mixed gas thereof. Of these, hydrogen gas is preferred. Hydrogen gas is suitable for removing organic substances adhering to the surface of the metal particles.
The reducing gas may be mixed with an inert gas such as nitrogen, helium, argon, neon, krypton, or xenon. In this case, there is an effect that plasma is easily generated.

  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 necessary may be used.

Furthermore, when a porous conductive layer containing copper is formed, 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 is obtained, and a porous conductive layer having good adhesion to the substrate is formed. Because it can.

The firing temperature may be any temperature that allows the metal particles to be sintered, and is appropriately selected according to the type, particle diameter, firing method, and the like of the metal particles. Especially, it is preferable that a calcination temperature is below the heat-resistant temperature of a base material, and the inside of the range of 100 to 150 degreeC is preferable if silver particle is made into an example.
The firing time is appropriately selected according to the type of metal particles, the firing method, and the like. For example, when silver particles are fired by heat treatment, the firing time is preferably within a range of 10 minutes to 120 minutes, and more preferably within a range of 15 minutes to 40 minutes. For example, when copper particles are fired by hydrogen plasma, the firing time is preferably within a range of 1 minute to 10 minutes, and more preferably within a range of 2 minutes to 5 minutes.

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

  Examples of the material for the adhesive layer include a thermoplastic resin and a photosensitive resin whose adhesiveness or adhesiveness is reduced by light irradiation.

  The thermoplastic resin is not particularly limited as long as it can adhere the porous conductive layer and the substrate to be transferred, and is appropriately selected according to the type of the substrate to be transferred onto which the laminate is transferred. . For example, a general thermoplastic resin used for the transfer foil can be used. Moreover, the thermoplastic resin should just be heated, fuse | melted or softened, and should just express adhesiveness or adhesiveness, and curable resin which a part hardens | 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 Conventional adhesives such as urethane resins, ionomer resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, polyester resins, and polyamide resins can be widely used. A thermoplastic resin may be used individually by 1 type, and may be used in combination of 2 or more type.

  As the photosensitive resin whose tackiness or adhesiveness is reduced by light irradiation, for example, it is cured by irradiation with light of a specific wavelength such as ultraviolet ray, visible light, infrared ray, etc., and the tackiness or adhesiveness is lowered, and In the non-light-irradiated portion, a material capable of bonding the porous conductive layer and the substrate to be transferred can be used. Specifically, known materials such as polyfunctional (meth) acrylic resins formulated with photopolymerization initiators or photocurable varnishes formulated with epoxy resins with photoacid generators or photobase generators are widely used. it can. Also, a solvent dilution type, a W / O emulsion type, or a non-sol type that does not contain a solvent may be used. Such photosensitive resin may be used individually by 1 type, and may be used in combination of 2 or more type.

  Further, the adhesive layer may contain an additive other than the thermoplastic resin or the photosensitive resin. In the case of a thermoplastic resin, examples of the additive include a dispersant, a filler, a plasticizer, and an antistatic agent.

  When a thermoplastic resin is used, the adhesive layer 4 may be formed on the entire surface of the base material 2 as illustrated in FIG. 1, and a pattern is formed on the base material 2 as illustrated in FIG. It may be formed. When the adhesive layer 4 is formed in a pattern on the substrate 2 as shown in FIG. 5A, as shown in FIG. 5C, even if the laminate 1 is not partially transferred. The pattern of the porous conductive layer 3 can be transferred onto the transfer substrate 11.

Moreover, when using the photosensitive resin 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 so that it may illustrate in Fig.6 (a).
FIGS. 6A to 6D are process diagrams showing another example of a method for producing a conductive substrate using the laminate of the present invention, and the adhesive layer 4 is reduced in adhesiveness or adhesiveness by light irradiation. This 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 substrate 2 is prepared, and light 16 is passed through the photomask 15 to the adhesive layer 4. Is irradiated in a pattern to reduce the adhesiveness or adhesiveness of the light-irradiated portion of the adhesive layer 4 to form the low adhesive portion 4b. Next, as shown in FIGS. 6 (b) to 6 (c), the adhesive layer 4 of the laminate 1 and the transferred substrate 11 are arranged so as to be in contact with each other, and are brought into close contact with each other. Then, as shown in FIG.6 (d), the base material 2 side is peeled. Since the adhesive layer 4 includes an adhesive portion 4a that is a non-light-irradiated portion and a low-adhesion portion 4b that is a light-irradiated portion and has reduced adhesiveness or adhesiveness, the adhesive portion 4a adheres to the substrate 11 to be transferred. However, in the low adhesion part 4b, the adhesion to the transfer substrate 11 is lowered. Therefore, when the base material 2 side is peeled off, the porous conductive layer 3 and the adhesive layer 4 are peeled off together with the base material 2 at the low adhesion portion 4b, and the porous conductive material is adhered to the transferred substrate 11 at the adhesion portion 4a. Layer 3 is transferred. Thereby, the electroconductive base material 10 which has the 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 transfer substrate 11 without partially transferring the laminate 1.

  The thickness of the adhesive layer is not particularly limited as long as the foil of the present invention can be cut when transferring the laminate of the present invention to the substrate to be transferred. The transfer method, the type of substrate to be transferred, etc. Is appropriately selected. 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, there is a possibility that the adhesion to the substrate to be transferred will 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 the laminate of the present invention is transferred, which may cause damage to the substrate to be transferred. For example, when the substrate to be transferred is a paper substrate, some paper substrates are difficult to transfer depending on the type. In that case, the thickness of the adhesive layer is compared in the above range from the viewpoint of transferability. It is preferable to be thick. Moreover, when transferring the laminated body of this invention to a to-be-transferred base material by integral molding, such as injection molding, it is preferable that the thickness of an contact bonding layer is comparatively thick also in the said range.

  Examples of the method for forming the adhesive layer include a method in which a resin composition is applied on a porous conductive layer and dried. As a coating method of the resin composition, it can be applied by appropriately selecting from general coating methods.

Further, as illustrated in FIG. 5B, the non-adhesive layer 5 may be formed in a pattern on the adhesive layer 4. Also in this case, the pattern of the porous conductive layer 3 can be transferred onto the transfer substrate 11 as shown in FIG.
Examples of the material for the non-adhesive layer include a thermoplastic resin that does not melt at a temperature at which the adhesive layer melts, a thermosetting resin, and a photocurable resin.
The thickness of the non-adhesive layer may be any thickness that allows the adhesive layer and the substrate to be transferred to be bonded when the laminate of the present invention is transferred to the substrate to be transferred. It is appropriately selected depending on the type of transfer substrate. Specifically, the thickness of the non-adhesive layer is preferably in the range of 100 nm to 3 μm.
Examples of the method for forming the non-adhesive layer include a method in which the resin composition is applied in a pattern on the adhesive layer, dried, and cured as necessary. As a coating method of the resin composition, it can be applied by appropriately selecting from general coating methods.

3. Base material The base material used for this invention supports said porous conductive layer and contact bonding layer.
The substrate is not particularly limited as long as the porous conductive layer can be formed. Examples thereof include inorganic substrates such as glass substrates and ceramic substrates, metal substrates, resin substrates, and paper substrates. A material etc. can be used.
Especially, it is preferable that a base material is a resin base material. In the present invention, since the porous conductive layer can be formed by sintering metal particles at a low temperature, it is less likely to damage the substrate, and it is not necessary to use a highly heat-resistant substrate. A low substrate can also be used. In particular, it is very useful in that an inexpensive general-purpose plastic resin substrate such as polyethylene terephthalate can be used.

  A general resin substrate can be used as the resin substrate. Preferred examples of the resin substrate include polyimide, polyamide, polyamideimide, polyethylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, polyether ether ketone, polyether sulfone, polycarbonate, polyether imide, epoxy resin, phenol resin, and 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, an inexpensive general-purpose plastic resin base material such as polyethylene terephthalate is preferable.

  The substrate may be flexible or rigid, and is appropriately selected according to the method for transferring the laminate of the present invention to the substrate to be transferred. Especially, it is preferable that a base material has flexibility, and it is more preferable that it is a resin base material which has flexibility from the reason mentioned above.

Further, a release layer may be formed on the surface of the substrate, or a release treatment may be performed. This is because peeling between the substrate and the porous conductive layer or the protective layer becomes easy.
Examples of the material for the release layer include a fluorine release agent, a silicone release agent, and a wax release agent. Examples of the method for forming the release layer include a method in which a release agent is applied by a coating method such as dip coating, spray coating, or roll coating.
Examples of the mold release treatment include surface treatment such as fluorine treatment and silicone treatment.

  Although it does not specifically limit as thickness of a base material, In the case of an inorganic base material, it is about 0.1 mm-10 mm normally, Preferably it exists in the range of 0.5 mm-5 mm. On the other hand, in the case of a resin base material, the thickness of the base material is usually about 1.0 μm to 1000 μm. When the thickness of the resin base material is within the above range, deformation of the base material is suppressed when forming the porous conductive layer, which is preferable in terms of shape stability of the formed porous conductive layer. This is preferable in terms of flexibility when the machining is performed continuously.

4). Other Configurations The laminate of the present invention may have other configurations as necessary in addition to the above-described base material, porous conductive layer, and adhesive layer. For example, an antistatic layer, a heat-resistant protective layer, a friction-resistant layer, a slipping layer, or the like may be provided on the surface of the substrate opposite to the surface on which the porous conductive layer is formed. Moreover, the protective layer may be formed between the base material and the porous conductive layer. Hereinafter, the protective layer will be described.

(Protective layer)
In the present invention, as illustrated in FIG. 7A, a protective layer 6 may be formed between the base material 2 and the porous conductive layer 3. As shown in FIG. 7B, the protective layer 6 is the outermost layer of the conductive substrate 10 after the porous conductive layer 3 is transferred from the laminate 1 to the transfer substrate 11, The porous conductive layer 3 can be protected from abrasion, light, chemicals, and the like. Moreover, a porous conductive layer can be insulated by setting it as the protective layer which has insulation.

The material of the protective layer may be any material that can protect the porous conductive layer and has an insulating property, and examples thereof include an ultraviolet curable resin and an electron beam curable resin. The protective layer may further contain a filler.
Moreover, you may use a protective film as a protective layer.

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

  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 within the above range, surface properties such as excellent high hardness, scratch resistance, chemical resistance and stain resistance can be obtained, and further excellent moldability and shape followability can be obtained. it can.

5. Applications The laminate of the present invention can be used for the production of conductive substrates as described later. For example, printed wiring boards, electromagnetic shielding materials, antennas, power semiconductors, noise filters, capacitor electrodes, various sensor electrodes ( Touch sensors, biosensors, temperature sensors, gas sensors, optical sensors, pressure sensors, flow sensors), display electrodes, solar cell electrodes, IC cards, RFID, etc., as well as bonding materials and connector materials it can.
The laminate of the present invention can be used as an electromagnetic wave shielding layer for preventing unauthorized reading of information recorded on a non-contact type IC card and a conductive layer for modulating the resonance frequency. For example, a porous conductive layer can be applied to a part of the card and transported in a state where reading cannot be performed, and the adhesive layer can be scratched and removed 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 adhesive force of the adhesive layer.
The laminate of the present invention can also be used to form designs, designs, characters, etc. that take advantage of the color and gloss of the porous conductive layer.

B. The manufacturing method of an electroconductive base material The manufacturing method of the electroconductive base material of this invention has two embodiments. In the following, each embodiment will be described separately.

1. 1st embodiment The manufacturing method of the electroconductive base material of this embodiment is the preparation process which prepares the above-mentioned laminated body, and the transcription | transfer process which transfers the contact bonding layer and porous conductive layer of the said laminated body on a to-be-transferred base material. It is a manufacturing method characterized by having.

  2 (a) to 2 (c) and FIGS. 3 (a) to 3 (c) are process diagrams showing an example of a method for producing a conductive substrate according to the present embodiment. 2 (a) to 2 (c) and FIGS. 3 (a) to 3 (c) have been described in detail in the above “A. Laminate”, description thereof is omitted here.

  In this embodiment, 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, and apparently the component derived from the porous conductive layer and the adhesive layer By becoming a mixture, thermal diffusion can be made difficult to occur. Therefore, in the transfer step, heat is difficult to escape, so there is no need to heat excessively, which is advantageous for thermal transfer.

  Moreover, in this embodiment, as above-mentioned, the component derived from an contact bonding layer can be made into the inside of the hole of a porous conductive layer, and the adhesiveness of a porous conductive layer and an contact bonding layer can be improved. Therefore, in the transfer step, the adhesive layer and the porous conductive layer can be satisfactorily transferred onto the transfer substrate, and excellent transferability can be obtained.

  In this embodiment, as described above, since the resin contained in the adhesive layer can enter the pores of the porous conductive layer, in the transfer step, the resin contained in the adhesive layer is the porous conductive layer. And the oxidation of the porous conductive layer can be suppressed. Accordingly, it is possible to suppress a decrease in conductivity of the porous conductive layer in the transfer process.

  Moreover, in this embodiment, since the laminate has a porous conductive layer, the foil cutting property is good, and the adhesive layer and the porous conductive layer of the laminate can be satisfactorily transferred onto the substrate to be transferred. . Furthermore, as illustrated in FIGS. 3A to 3C, when the pattern of the adhesive layer and the porous conductive layer of the laminate is transferred onto the transfer substrate, it can be transferred with high resolution.

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

  In this embodiment, since the porous conductive layer can be formed by sintering metal particles at a low temperature, it is not necessary to use a highly heat-resistant substrate as the substrate of the laminate. Low substrates can also be used. In particular, an inexpensive general-purpose plastic resin substrate such as polyethylene terephthalate can be used. Therefore, the manufacturing cost can be reduced.

  Hereinafter, 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, since it described in detail in said "A. laminated body" about the laminated body, description here is abbreviate | omitted.

(2) Transfer process The transfer process in this embodiment is a process of transferring the adhesive layer and the porous conductive layer of the laminate onto the transfer 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 is appropriately selected depending on the use of the conductive substrate. 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 method can adhere the adhesive layer to a predetermined position on the substrate to be transferred. Instead, it is appropriately selected according to the material of the adhesive layer.

In the case of using a thermoplastic resin, examples of the thermal transfer method include a method using a heating roller or a hot stamp, a hot pressing method, and the like.
Examples of the thermal transfer method include a method using a mold as illustrated in FIGS. 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 prepared first. In addition, the laminated body 1 is the same as the laminated body 1 shown in FIG. Next, as shown in FIG. 8A, the laminated body 1 is laminated so that the adhesive layer 4 and the transferred substrate 11 are in contact with each other, and the laminated body 1 and the transferred substrate 11 are bonded to the base of the laminated body 1. The material 2 is arranged in a molding die having the upper die 23 and the lower die 24 so that the material 2 faces the upper die 23 and the transferred substrate 11 faces the lower die 24. Subsequently, as shown in FIG. 8B, the mold 1 is heated and clamped to mold the laminate 1 and the transfer substrate 11, and at the same time, the laminate 1 is thermally transferred to the transfer 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 substrate 11 to be transferred are taken out from the mold, and the substrate 2 is peeled from the laminate 1 as shown in FIG. 8 (d). To do. As a result, the conductive base material 10 in which the adhesive layer 4 and the porous conductive layer 3 are sequentially laminated on the transfer base material 11 is obtained.

  In the case of using a thermoplastic resin, as illustrated in FIGS. 3A to 3C, when the pattern of the adhesive layer and the porous conductive layer is thermally transferred onto the substrate to be transferred, a thermal transfer method is used. Examples of the method include a method using a laser beam or a thermal head.

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

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

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

  Further, in the case of a method using a mold as illustrated in FIGS. 8A to 8D, when the laminate and the substrate to be transferred are arranged in the mold, the laminate and the transferred group are placed on the mold. The material may be vacuum-sucked so that the laminate and the substrate to be transferred conform to the shape of the mold, or the laminate and the substrate to be transferred are laminated and then heated and molded in a softened state. It may be sandwiched between molds.

After adhering the adhesive layer of the laminate on the substrate to be transferred, it is usually porous in the area where the adhesive layer is adhered on the substrate to be transferred by physically separating the laminate from the substrate side. The substrate can be peeled from the conductive layer.
Further, in the case of a method using a mold as illustrated in FIGS. 8A to 8D, in the case of a single-wafer laminate, a molded product in which the laminate and the substrate to be transferred are integrated. After taking out from a shaping | molding die, the base material of a laminated body is peeled from a molded article. In the case of a long laminate, the substrate is peeled from the laminate when a molded product in which the laminate and the transferred substrate are integrated is taken out of the mold.

2. Second Embodiment A method for producing a conductive substrate according to the present embodiment includes a preparation step for preparing the above-described laminate, and arranging the laminate in a molding die, and a molten resin for a substrate to be transferred in the molding die. Injection and solidification to form a substrate to be transferred, and at the same time, a molding and transfer step for transferring the laminate to the substrate to be transferred, and a peeling step for peeling the substrate of the laminate Is a manufacturing method characterized by

The manufacturing method of the electroconductive base material of this embodiment is demonstrated with reference to drawings.
9A to 9D are process diagrams showing an example of a method for producing a conductive substrate according to this embodiment. First, the laminated body 1 as shown to Fig.9 (a) is prepared. In addition, the laminated body 1 is the same as the laminated body 1 shown in FIG. Next, as shown in FIG. 9A, the laminate 1 is placed in a forming die having a fixed die 21 and a movable die 22 so that the base material 2 faces the fixed die 21. Subsequently, as shown in FIG. 9 (b), the mold is clamped, the transfer substrate molten resin 11a is injected into the mold, cooled and solidified, and simultaneously with the molding of the transfer substrate. Then, the laminate 1 is transferred to the substrate to be transferred. Thereby, the to-be-transferred base material which is a resin molding, and the laminated body 1 are laminated | stacked and integrated. Next, as shown in FIG. 9 (c), the integrated laminate 1 and the substrate to be transferred 11 are taken out of the mold, and the substrate 2 is peeled from the laminate 1 as shown in FIG. 9 (d). To do. As a result, the conductive base material 10 in which the adhesive layer 4 and the porous conductive layer 3 are sequentially laminated on the transfer 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 introduced into the pores of the porous conductive layer, and apparently the component derived from the porous conductive layer and the adhesive layer By becoming a mixture, thermal diffusion can be made difficult to occur. Therefore, in the molding and transfer process, heat does not easily escape, so it is not necessary to heat excessively, which is advantageous for transfer.

  Moreover, in this embodiment, as above-mentioned, the component derived from an contact bonding layer can be made into the inside of the hole of a porous conductive layer, and the adhesiveness of a porous conductive layer and an contact bonding layer can be improved. Therefore, in the molding and transfer process, the adhesive layer and the porous conductive layer can be satisfactorily transferred onto the transfer substrate, and excellent transferability can be obtained.

  In this embodiment, as described above, since the resin contained in the adhesive layer can enter the pores of the porous conductive layer, the porous conductive layer is included in the adhesive layer in the molding and transfer process. It is possible to protect the porous conductive layer from being oxidized. Therefore, it is possible to suppress a decrease in conductivity of the porous conductive layer in the molding and transfer process.

  Moreover, in this embodiment, since the to-be-transferred base material and laminated body which are resin moldings are laminated | stacked and integrated, formation of the porous conductive layer to the to-be-transferred base material which is a three-dimensional object is possible.

  Moreover, in this embodiment, since a laminated body has a porous conductive layer, foil cutting property and resolution are favorable. Therefore, for example, when the laminate 1 as shown in FIGS. 5A and 5B is used, the transfer can be performed with good foil breakage and with high resolution.

  In this embodiment, since the porous conductive layer can be formed by sintering metal particles at a low temperature, it is not necessary to use a highly heat-resistant substrate as the substrate of the laminate. Low substrates can also be used. In particular, an inexpensive general-purpose plastic resin substrate such as polyethylene terephthalate can be used. Therefore, the manufacturing cost can be reduced.

  Hereinafter, 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, since it described in detail in said "A. laminated body" about the laminated body, description here is abbreviate | omitted.
In this embodiment, a thermoplastic resin is used as the material for the adhesive layer.

(2) Molding and transfer step In the molding and transfer step in this embodiment, the laminate is placed in a molding die, a molten resin for a substrate to be transferred is injected into the molding die, solidified, and a transferred group. At the same time as molding the material, the laminate is transferred to the substrate to be transferred.

  When the laminated body is arranged in the mold, the laminated body is arranged so that the adhesive layer contacts the molten resin for the transferred substrate when the molten resin for the transferred substrate is injected into the mold. At this time, a sheet stack may be disposed in the mold, and a predetermined region of the long stack may be inserted intermittently.

When placing the laminate on the mold, it may be heated to bring the laminate into close contact with the mold. At this time, the mold may be heated and the laminate may be vacuum-adhered to the mold, and the laminate may be heated and preformed so that the laminate conforms to the shape of the mold. You may make a laminated body closely_contact | adhere.
In the latter case, the heating temperature is preferably equal to or higher than the glass transition temperature of the substrate of the laminate and less than the melting temperature or the melting point, and more preferably a temperature near the glass transition temperature of the substrate. The vicinity of the glass transition temperature means a range of glass transition temperature ± 5 ° C.

  As the molten resin for the substrate to be transferred, a thermoplastic resin and a thermosetting resin that can be injection-molded can be used. The thermosetting resin includes a two-component curable resin. As the molten resin for a substrate to be transferred, one kind may be used alone, or two or more kinds may be used.

In the case where the molten resin for the substrate to be transferred is a thermoplastic resin, the thermoplastic resin is injected in a fluid state by heating and melting, and is cooled and solidified. Further, when the molten resin for a substrate to be transferred is a thermosetting resin, the uncured resin composition is appropriately heated, injected in a fluid state, and heated to be solidified. Thereby, the laminated body is integrated with the molded substrate.
The heating temperature of the transferred resin for the transfer substrate is different depending on the type of the transfer resin for the transfer substrate, but is, for example, about 80 ° C. to 280 ° C.

  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 transfer substrate can be obtained.

When the pattern of the adhesive layer and the porous conductive layer is transferred to the substrate to be transferred, the laminate 1 in which the adhesive layer 4 as illustrated in FIG. 5A is previously formed in a pattern may be used. Alternatively, the laminate 1 in which the non-adhesive layer 5 is formed in a pattern on the adhesive layer 4 as illustrated in FIG. 5B may be used.
In addition, when transferring the pattern of the porous conductive layer to the substrate to be transferred, in addition to the above, a laminate in which the porous conductive layer 3 as illustrated in FIG. Body 1 may be used.

  After the molten resin for the substrate to be transferred is solidified, a molded product in which the laminate and the molded substrate to be transferred 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 removing a molded product in which the laminate and the molded substrate to be transferred are integrated from the mold, the substrate of the laminate is peeled from the molded product. In the case of a long laminate, the substrate is peeled from the laminate when a molded product in which the laminate and the molded substrate to be transferred are integrated is taken out of the mold.
Thereby, the electroconductive base material by which the contact bonding layer and the porous electroconductive layer were laminated | stacked in order on the to-be-transferred base material which is a resin molding is obtained.

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

In the present invention, since the conductive substrate is produced by the above-described method for producing a conductive substrate, a porous conductive layer having good conductivity can be formed. For example, when forming a pattern of a porous conductive layer, a high-resolution pattern can be formed.
Moreover, in this invention, since a conductive base material is produced with the manufacturing method of the above-mentioned conductive base material, manufacturing cost can be reduced.

  Hereinafter, the process in the manufacturing method of the electronic device of this embodiment will be described.

1. Conductive base material preparation process The conductive base material preparation process in this invention is a process of producing a conductive base material with the manufacturing method of the above-mentioned conductive base material.
In addition, since it described in detail in the said "B. manufacturing method of an electroconductive base material" about the manufacturing method of an electroconductive base material, description here is abbreviate | omitted.

2. Electronic device Examples of the electronic device in the present invention include a printed wiring board, an electromagnetic wave shielding material, an antenna, a power semiconductor, a noise filter, a capacitor electrode, and various sensor electrodes (touch sensor, biosensor, temperature sensor, gas sensor, optical sensor). , Pressure sensor, flow sensor), display electrode, solar cell electrode, IC card, RFID, bonding material, connector material, and the like.
When the electronic device of the present invention is, for example, a non-contact type IC card, the porous conductive layer is an electromagnetic wave shielding layer for preventing unauthorized reading of information recorded on the non-contact type IC card, and modulates the resonance frequency. It can be used as a conductive layer. In this case, for example, it is possible to temporarily apply a porous conductive layer to the card, and then scratch and remove the adhesive layer together. Since the electronic device of the present invention has a porous conductive layer, it can be easily peeled off by scratching by controlling the adhesive force of the adhesive layer.

  The method for producing an electronic device of the present invention may have other steps as needed in addition to the conductive substrate manufacturing step. Other steps are appropriately selected depending on the electronic device.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described in more detail with reference to 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), 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 the temperature was maintained for 20 minutes. Thereafter, 41.3 g (manufactured by Guangei Chemical Industry Co., Ltd.) of 3-ethoxypropylamine was added, and the mixture was heated and stirred at 100 ° C. for 10 minutes. After cooling this mixed liquid to 10 ° C. using an ice bath, a solution prepared by dissolving 10.0 g of hydrazine monohydrate in 18.5 g of PGME (manufactured by Kanto Chemical Co., Ltd.) was added for 10 minutes. Stir. Thereafter, the reaction solution was heated to 100 ° C., and the temperature was maintained 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 with 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) and 56 parts by mass of propylene glycol monomethyl ether (PGME) are mixed as a polymer dispersant, and a paint shaker (manufactured by Asada Tekko) As a preliminary dispersion, 2 mm zirconia beads were used for 1 hour, and as a main dispersion, 0.1 mm zirconia beads were used for 2 hours to obtain a copper particle dispersion 1.

[Production Example 1: Production of conductive film A]
Copper film dispersion 1 is applied to 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 hot air dryer, and a film having a bronze gloss Got. Thereafter, while introducing hydrogen gas at an introduction pressure of 20 Pa, using a microwave surface wave plasma processing apparatus (MSP-1500, manufactured by Micro Electronics Co., Ltd.), firing was performed at a microwave output of 450 W for 240 seconds to form a porous conductive layer. A conductive film A was obtained.

[Production Example 2: Production of conductive film B]
A conductive film B having a porous conductive layer was obtained by baking for 120 seconds at a microwave output of 450 W by the same production method as that for the conductive film A, except that the PET film was changed to a film thickness of 5 μm.

[Production Example 3: Production of conductive film C]
Copper was formed into a film 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 of the conductive layer was evaluated by measuring the sheet resistance value by a four-probe method using a surface resistance meter (“Loresta GP” manufactured by Dia Instruments, PSP type probe). The sheet resistance values of the porous conductive layers of the conductive films A and B were both 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. For the produced conductive film, carbon is deposited on the conductive layer as a protective layer by vacuum vapor deposition and platinum by sputtering, and then tungsten is laminated using FIB (focused ion beam, FB-2100 made by Hitachi High-Tech). Then, the cross section of the conductive layer was produced. Then, the cross section of the conductive layer was observed using a SEM (Hitachi High-Tech S-4800) with the substrate inclined 45 °, 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. In all of the conductive films A, B, and C, the film thickness of the conductive layer was 400 nm. From this result, it was found that the volume resistance value of the conductive films A and B was 8 μΩ · cm, and the volume resistance value 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. In the SEM image obtained in the above film thickness measurement, the area of the hole and the area of the conductive layer were calculated, and the area of the hole was divided by the area of the conductive layer to determine 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 pores 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) to TM-R850 (LV-NT) K3 manufactured by Dainichi Seika, which is an adhesive, and stirring sufficiently. This coating solution was applied on the porous conductive layer of the conductive film A with 10 mils of applicator and dried at 90 ° C. for 1 minute with a hot air dryer.

(Transcription)
Next, a laminated film C001 (Sumitomo Chemical 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 coating surface of the conductive film A described above was stacked, and a heat laminating process was performed using a multi-laminator GL835PRO manufactured by Japan GBC at a temperature of 130 ° C., a GAP of 1 mm or less, and a conveyance speed of 0.3 m / min. Thereafter, the PET film was peeled off.
The porous conductive layer was 100% transferred to the transfer substrate, and the sheet resistance value after transfer was 0.22Ω / □.

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

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

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

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

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

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

(Transcription)
When the conductive film B on which the adhesive layer was formed was set as a transfer ribbon on a thermal head printer (Zebra140Xi4) and a print test was performed using gloss-coated paper as a substrate to be transferred, a wiring with a line width of 127 μm and a total length of 10 cm was found. It was formed and continuity was confirmed by a 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]
Except that the conductive film C was used instead of the conductive film A, transfer was performed in the same manner as in Example 2, and transfer was not possible at all.

[Comparative Example 3]
Except that the conductive film C was used instead of the conductive film A, transfer was performed in the same manner as in Example 3, and transfer was not possible at all.

[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, transfer was not possible at all.

[Comparative Example 5]
A 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, and 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, transfer was not possible at all.

[Production Example 4: Production of conductive film D]
Nano Ag ink (trade name MDot CF107, manufactured by Mitsuboshi Belting) was diluted 40% with pentanediol, and then applied to PET film (trade name: Cosmo Shine A4100, manufactured by Toyobo Co., Ltd., film thickness 100 μm) using Miyabar # 4 and warm air It dried and baked for 30 minutes at 120 degreeC with the dryer, and obtained the conductive film D which has silver luster and has 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 as an adhesive was applied on the porous conductive layer of the conductive film D with a Miya bar # 4, dried at 90 ° C. for 3 minutes with a hot air dryer, and transfer In Example 1, an adhesive layer was formed and transferred in the same manner as in Example 1 except that gloss coated paper was used as the substrate to be transferred and the temperature was 130 ° C.
The porous conductive layer was 100% transferred to the transfer substrate, and the sheet resistance value after transfer was 0.20Ω / □.

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

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

DESCRIPTION OF SYMBOLS 1 ... Laminated body 2 ... Base material 3 ... Porous conductive layer 4 ... Adhesive layer 6 ... Protective layer 10 ... Conductive base material 11 ... Transferred base material

Claims (7)

A substrate;
A porous conductive layer formed on the substrate;
And a bonding layer formed on the porous conductive layer.   The laminate according to claim 1, wherein the substrate is a resin substrate.   The laminate according to claim 1 or 2, wherein a protective layer is formed between the substrate and the porous conductive layer. A preparation step of preparing the laminate according to any one of claims 1 to 3,
And a transfer step of transferring the adhesive layer and the porous conductive layer of the laminate onto the substrate to be transferred.   The method for producing a conductive substrate according to claim 4, wherein in the transfer step, the pattern of the adhesive layer and the porous conductive layer of the laminate is transferred onto the transfer substrate. A preparation step of preparing the laminate according to any one of claims 1 to 3,
The laminate is placed in a mold, and a molten resin for a transfer substrate is injected into the mold and solidified to form the transfer substrate, and at the same time, the laminate is transferred to the transfer substrate. Molding and transfer processes,
A method for producing a conductive substrate, comprising: a peeling step of peeling the substrate of the laminate.   A method for producing an electronic device, comprising a step of producing a conductive substrate by producing a conductive substrate by the method for producing a conductive substrate according to claim 4.

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