Conductive Resin Composition and Method for Manufacturing Electronic Component

Abstract

The manufacturing method of the electronic component of the present invention has: a preparation process for preparing an electrode formation body for an electronic component; and an electrode formation process for forming an electrode on the outer surface of the electrode formation body for the electronic component. In this electrode formation process, a conductive resin layer is formed on the electrode formation body for the electronic component using a conductive resin composition. The conductive resin composition contains metal powder, a resin binder, and an organic solvent. In the metal powder, 20.0 mass% or more is flaky metal powder, and in the resin binder, 70.0 mass% or more is a polysiloxane resin. By the present invention, it is possible to provide a manufacturing method of an electronic component that has high moisture resistance, has fewer restrictions in terms of design and manufacturing, and has high manufacturing efficiency.

Description

Technical Field

[0001] The present invention relates to a conductive resin composition for forming an electrode on an electrode forming body for an electronic component such as a laminate for a laminated electronic component or a cathode body to be formed for a solid electrolytic capacitor, for manufacturing an electronic component. Further, the present invention relates to a method for manufacturing an electronic component using the conductive resin composition. Background Art

[0002] In recent years, since electronic devices are used in harsher environments than before, there is a demand that electronic components mounted on the electronic devices do not malfunction even when used in harsher environments than before.

[0003] Specifically, for example, in the case of mobile devices such as smartphones, it is required that even when these mobile devices fall and are impacted, no cracks or interfacial peeling occur at the connection portion between the substrate and the electronic component, so that the electronic component does not fall off the substrate, or no cracks occur in the electronic component itself, that is, a high impact resistance.

[0004] In addition, in the case of electronic devices mounted on an automobile, for these electronic devices as well, it is required that even when impacted by vibrations during driving, no cracks or interfacial peeling occur at the connection portion between the substrate and the electronic component, so that the electronic component does not fall off the substrate, or no cracks occur in the electronic component itself, that is, a high impact resistance.

[0005] Therefore, Patent Document 1 discloses a laminated electronic component having an external electronic electrode in which a conductive resin layer is formed on a base metal layer formed by electroplating. In this laminated electronic component, by forming a conductive resin layer on the base metal layer, even when the substrate on which the laminated electronic component is mounted is flexed, the conductive resin layer can relieve stress, thereby being able to suppress the generation of cracks.

[0006] As the conductive resin composition used in the formation of the conductive resin layer, a conductive resin containing an epoxy resin excellent in heat resistance, moisture resistance, and adhesiveness has been conventionally used. For example, Patent Document 2 discloses a conductive resin composition containing a conductive filler, a chelate-forming substance, a phenolic resin, a modified epoxy resin, and a boron compound.

[0007] Prior Art Documents

[0008] Patent Documents

[0009] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2009-295602

[0010] Patent Document 2: International Publication WO2016 / 104232 Summary of the Invention

[0011] Technical Problem to be Solved by the Invention

[0012] Since mobile devices and automobiles are sometimes exposed to environments with high humidity, the electronic components mounted on mobile devices and automobiles are required to have high moisture resistance reliability to prevent moisture from entering the interior.

[0013] However, the conductive resin layer formed of a conductive resin composition having an epoxy resin as the main component of the resin component, although having a certain degree of moisture resistance, is insufficient for the high moisture resistance required for electronic components used in mobile devices or automobiles.

[0014] In addition, when using a conductive resin composition having an epoxy resin as the main component of the resin component, there are design restrictions such as the need to incorporate butyral resin in the epoxy resin to adjust flexibility.

[0015] Therefore, the first object of the present invention is to provide a conductive resin composition for forming an electrode of an electronic component having high moisture resistance. The second object of the present invention is to provide a conductive resin composition for forming an electrode of an electronic component having high moisture resistance, with fewer design and manufacturing restrictions and higher manufacturing efficiency.

[0016] Technical Means for Solving the Problem

[0017] The inventors of the present invention repeatedly conducted in-depth research to solve the above technical problems. As a result, the inventors found that: by using a conductive resin composition containing a given amount of polysiloxane resin as a resin binder to form a conductive resin layer on an electrode forming body for an electronic component, compared with the case of using a conductive resin composition having an epoxy resin as the main component of the resin binder, an electronic component with excellent moisture resistance can be obtained, and design restrictions can be reduced, thus completing the present invention.

[0018] That is, the present invention (1) provides a method for manufacturing an electronic component, which includes:

[0019] A preparation step of preparing an electrode forming body for an electronic component; and

[0020] An electrode forming step of forming an electrode on the outer surface of the electrode forming body for the electronic component,

[0021] In this electrode forming step, a conductive resin composition is used to form a conductive resin layer on the electrode forming body for the electronic component. The conductive resin composition contains metal powder, resin binder, and organic solvent. In the metal powder, 20.0% by mass or more is flaky metal powder, and in the resin binder, 70.0% by mass or more is polysiloxane resin.

[0022] In addition, the present invention (2) provides a conductive resin composition containing metal powder, resin binder, and organic solvent.

[0023] Among the metal powder, 20.0% by mass or more is flaky metal powder.

[0024] Among the resin binder, 70.0% by mass or more is polysiloxane resin.

[0025] In addition, the present invention (3) provides the conductive resin composition according to (2), wherein 80.0% by mass or more of the resin binder is polysiloxane resin.

[0026] In addition, the present invention (4) provides the conductive resin composition according to (2) or (3), wherein, based on 100.0 parts by mass of the metal powder, the content of the resin binder is 2.5 to 35.0 parts by mass.

[0027] In addition, the present invention (5) provides the conductive resin composition according to any one of (2) to (4), wherein the polysiloxane resin has an epoxy group.

[0028] In addition, the present invention (6) provides the conductive resin composition according to any one of (2) to (4), wherein the polysiloxane resin has a hydroxyl group.

[0029] In addition, the present invention (7) provides the conductive resin composition according to any one of (2) to (4), wherein the polysiloxane resin is a thermosetting polysiloxane resin.

[0030] In addition, the present invention (8) provides the conductive resin composition according to any one of (2) to (7), wherein the resin binder contains more than 0.0% by mass and 20.0% by mass or less of epoxy resin.

[0031] In addition, the present invention (9) provides the conductive resin composition according to any one of (2) to (8), wherein the aspect ratio of the flaky metal powder is 1.5 to 50.0.

[0032] In addition, the present invention (10) provides the conductive resin composition according to any one of (2) to (9), wherein the metal powder is at least one powder selected from powders of one or more of silver, copper, nickel, palladium, platinum, gold, and aluminum, powders containing alloys of one or more of these, silver-coated copper powder, and silver-coated nickel powder.

[0033] In addition, the present invention (11) provides the conductive resin composition according to any one of (2) to (10), which further contains a plasticizer.

[0034] In addition, the present invention (12) provides the conductive resin composition according to any one of (2) to (11), wherein, when a strain of 1% is applied at an angular frequency of 1 Hz to the conductive resin composition, the value of the phase difference δ between the strain and the stress generated by the strain is in the range of 32 to 88°.

[0035] In addition, the present invention (13) provides the conductive resin composition according to any one of (2) to (12), wherein the ratio of the viscosity of the conductive resin composition at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is in the range of 1.4 to 60.0.

[0036] In addition, the present invention (14) provides the conductive resin composition according to any one of (2) to (13), wherein the conductive resin composition is used for forming an external electrode of a laminated electronic component.

[0037] In addition, the present invention (15) provides the conductive resin composition according to any one of (2) to (13), wherein the conductive resin composition is used for forming a cathode of a solid electrolytic capacitor.

[0038] In addition, the present invention (16) provides the conductive resin composition according to (14), wherein the conductive resin composition is used for dip printing.

[0039] In addition, the present invention (17) provides the conductive resin composition according to any one of (2) to (16), wherein the moisture permeability obtained by the following moisture permeability measurement test is 80.0 mg or less.

[0040] <Moisture Permeability Measurement Test>

[0041] The conductive resin composition is cast on a PET film with a thickness of 250 μm and cured under the conditions of 200°C for 60 minutes. The obtained cured film is cut into a circle with a diameter of 7.5 mm and fixed with an adhesive in a manner that covers a 5 ml glass bottle containing 2 g of silica gel. The glass bottle is placed in a 750 ml container containing 100 ml of purified water in a state where the cured film does not contact the purified water and sealed, and then placed in a dryer set at 65°C and left standing for 15 hours. Then, the moisture permeability is calculated by the following formula (1):

[0042] Moisture permeability (weight increase) = weight of the glass bottle after being placed in the dryer - weight of the glass bottle before being placed in the dryer (1).

[0043] In addition, the present invention (18) provides a conductive resin composition according to (3), which is a conductive resin composition containing metal powder, resin binder, and organic solvent, wherein

[0044] when the metal powder is 100.0 parts by mass, the content of the resin binder is 5.0 to 25.0 parts by mass,

[0045] 80.0% by mass or more of the resin binder is a polysiloxane resin,

[0046] 20.0% by mass or more of the metal powder is a flaky metal powder,

[0047] when a strain of 1% is applied to the conductive resin composition at an angular frequency of 1 Hz, the value of the phase difference δ between the strain and the stress generated by the strain is in the range of 45 to 87°,

[0048] the ratio of the viscosity of the conductive resin composition at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is in the range of 1.5 to 20.0.

[0049] Advantages of the Invention

[0050] According to the present invention, a conductive resin composition for forming an electrode of an electronic component having high moisture resistance can be provided. In addition, according to the present invention, a conductive resin composition for forming an electrode of an electronic component having high moisture resistance, few restrictions in design and manufacturing, and high manufacturing efficiency can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a schematic perspective view showing a stacked electronic component.

[0052] Figure 2 is a schematic cross-sectional view showing a stacked electronic component mounted on a substrate.

[0053] Figure 3 is a graph showing the relationship between the film thickness and moisture permeability of the conductive resin layers in Example 14 and Comparative Example 5. DETAILED DESCRIPTION

[0054] The conductive resin composition of the present invention contains metal powder, resin binder, and organic solvent. 20.0% by mass or more of the metal powder is flaky metal powder, and 70.0% by mass or more of the resin binder is polysiloxane resin.

[0055] Refer to Figure 1 and Figure 2 to describe a schematic example of an electronic component obtained by using the conductive resin composition of the present invention. Figure 1It is a schematic perspective view showing a multilayer electronic component. Figure 2 It is a schematic cross-sectional view showing a multilayer electronic component mounted on a substrate. The multilayer electronic component 10 includes: a multilayer body 1 for a multilayer electronic component including a plurality of ceramic layers and a plurality of internal electrode layers, and external terminal electrodes 2 and 3 formed on the outer surfaces on both end sides of the multilayer body 1 for a multilayer electronic component and electrically connected to the internal electrode layers. The external terminal electrodes 2 and 3 include: a metal layer 4 formed on the outer surface of the multilayer body 1 for a multilayer electronic component, a conductive resin layer 5 formed on the surface of the metal layer 4, and a plating layer 6 formed on the surface of the conductive resin layer 5. That is, in the external terminal electrodes 2 and 3, the conductive resin layer 5 is disposed between the metal layer 4 and the plating layer 6. And the multilayer electronic component 10 is mounted on the substrate 8 by solder 7.

[0056] The conductive resin composition of the present invention contains metal powder, resin binder, and organic solvent.

[0057] The conductive resin composition of the present invention contains metal powder as a conductive material. As the metal powder, for example, powders containing one or more of silver powder, copper powder, nickel powder, palladium powder, platinum powder, gold powder, aluminum powder, etc., powders containing an alloy of one or more of silver, copper, nickel, palladium, platinum, gold, and aluminum, silver-coated copper powder, and silver-coated nickel powder can be cited.

[0058] In the conductive resin composition of the present invention, 20.0% by mass or more of all the metal powders is flaky metal powder. The content ratio of the flaky metal powder with respect to the total metal powder is 20.0 to 100.0% by mass, preferably 40.0 to 100.0% by mass, and particularly preferably 60.0 to 100.0% by mass. By making the content ratio of the flaky metal powder with respect to the total metal powder within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased.

[0059] The aspect ratio of the flaky metal powder is preferably 1.5 to 50.0, more preferably 2.0 to 30.0, and particularly preferably 5.0 to 20.0. By making the aspect ratio of the flaky metal powder within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased. It should be noted that in the present invention, the aspect ratio of the flaky metal powder is the ratio of the particle diameter to the particle thickness (thickness / diameter), and the aspect ratios of 50 metal powders arbitrarily selected in the observation of a scanning electron microscope (SEM) image are measured, and their average value is obtained.

[0060] When measured using a scanning electron microscope (SEM), the number average particle diameter of the flaky metal powder is preferably 0.1 to 20.0 μm, more preferably 0.3 to 15.0 μm, still more preferably 0.5 to 10.0 μm, and particularly preferably 1.0 to 5.0 μm. By making the number average particle diameter of the flaky metal powder within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased. It should be noted that in the present invention, regarding the number average particle diameter of the flaky metal powder when measured using a scanning electron microscope (SEM), the diameter of the longest part of the particle is taken as the particle diameter, and the particle diameters of 50 metal powders arbitrarily selected in the SEM (scanning electron microscope) image observation are measured, and the average value thereof is obtained as the number average particle diameter.

[0061] The specific surface area of the flaky metal powder is preferably 0.5 to 5.0 m 2 / g, and particularly preferably 0.6 to 4.0 m 2 / g. By making the specific surface area of the flaky metal powder within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased.

[0062] The metal powder contains flaky metal powder and spherical metal powder, and preferably "the content ratio of the spherical metal powder to the whole metal powder is 80.0% by mass or less, and the content of the flaky metal powder to the whole metal powder is 20.0% by mass or more", and particularly preferably "the content ratio of the spherical metal powder to the whole metal powder is 60.0% by mass or less, and the content of the flaky metal powder to the whole metal powder is 40.0% by mass or more". By making the content ratio of the flaky metal powder and the spherical metal powder within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased.

[0063] The cumulative 50% particle diameter (D 50 ) of the spherical metal powder is preferably 0.01 to 7.0 μm, and particularly preferably 0.03 to 5.0 μm. By making D 50 of the spherical metal powder within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased. It should be noted that in the present invention, for D 50 , a laser diffraction particle size distribution measuring device is used to obtain the 50% value (D 50 ) of the cumulative fraction on a volume basis.

[0064] The specific surface area of the spherical metal powder is preferably 0.2 to 3.0 m 2 / g, and particularly preferably 0.3 to 2.5 m 2 / g. By making the specific surface area of the spherical metal powder within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased.

[0065] In the conductive resin composition of the present invention, the resin binder contains at least a polysiloxane resin.

[0066] In the conductive resin composition of the present invention, 70.0% by mass or more of all the resin binders is a polysiloxane resin. In the conductive resin composition of the present invention, the content ratio of the polysiloxane resin relative to all the resin binders is 70.0 to 100.0% by mass, preferably 80.0 to 100.0% by mass, more preferably 90.0 to 100.0% by mass, and particularly preferably 95.0 to 100.0% by mass. By making the conductive resin composition contain the polysiloxane resin within the above range, the moisture resistance of the conductive resin layer can be increased, the change ratio of the moisture permeability with respect to the film thickness change becomes smaller, the design constraints can be reduced, the formability can be improved, and thus the manufacturing efficiency can be increased. As the polysiloxane resin, a thermosetting polysiloxane resin and a thermoplastic polysiloxane resin can be mentioned, and among them, a thermosetting polysiloxane resin is preferred. Among the thermosetting polysiloxane resins, a self-curing type resin that cures by heating even without using a curing agent and a curing agent-curing type resin that cures by a curing agent can be mentioned. As the self-curing type polysiloxane resin, for example, a polysiloxane resin having a hydroxyl group as a reactive functional group and curing by a dehydration condensation reaction by heating can be mentioned. In addition, as the curing agent-curing type polysiloxane resin, for example, a polysiloxane resin that cures by a crosslinking reaction of a hydrocarbon group such as an alkenyl group by heating with a catalyst added can be mentioned.

[0067] There is no particular limitation on the thermosetting polysiloxane resin. For example, a thermosetting polysiloxane resin in which the skeleton part of the resin contains a polysiloxane oligomer, a polyorganosiloxane, a dimeric organosiloxane, an organopolysiloxane, a dimeric organosiloxane, etc., and the skeleton part of the resin has one or more reactive functional groups can be mentioned. As the skeleton part of the curable polysiloxane resin, from the viewpoint of increasing the moisture resistance of the conductive resin layer, polyorganosiloxane and diorganopolysiloxane are preferred. The skeleton part of the thermosetting polysiloxane resin can be linear or branched.

[0068] There is no particular limitation on the reactive functional group of the thermosetting polysiloxane resin. For example, a hydroxyl group, an alkenyl group, a hydrosilyl group, a (meth)acryloyl group, an epoxy group, an amino group, a methanol group, a mercapto group, a carboxyl group, a phenol group, etc. can be mentioned. As the reactive functional group of the thermosetting polysiloxane resin, from the viewpoint of moisture resistance, a hydroxyl group and an alkenyl group are preferred, and from the viewpoint of adhesiveness, an epoxy group is preferred.

[0069] In the thermosetting polysiloxane resin, in addition to the reactive functional group, functional groups such as an alkyl group, an alkenyl group, and an aromatic group can be present on the side chain. As the side chain of the thermosetting polysiloxane resin, from the viewpoint of increasing the moisture resistance of the conductive resin layer, a methyl group and a phenyl group are preferred.

[0070] As the curing agent for the thermosetting polysiloxane resin that cures with a curing agent, there is no particular limitation. For example, platinum-based curing agents, titanium-based curing agents, aluminum-based curing agents, zinc-based curing agents, iron-based curing agents, phosphoric acid-based curing agents, etc. can be cited. As the reactive functional group of the thermosetting polysiloxane resin, when the polysiloxane resin has an epoxy group, known curing agents used in epoxy resins can be used. For example, amine-based curing agents such as ethylenediamine, organic acids such as oxalic acid, and acid anhydrides such as phthalic anhydride can be cited.

[0071] The molecular weight (weight-average molecular weight Mw) of the thermosetting polysiloxane resin is not particularly limited, and is preferably 1,000 to 300,000, and particularly preferably 2,000 to 200,000.

[0072] Within the range that does not impair the effects of the present invention, the conductive resin composition of the present invention may also contain a resin binder other than the polysiloxane resin. As the resin binder other than the polysiloxane resin, the following can be cited: epoxy resin, butyral resin, acetal resin, acrylic resin, polybutadiene resin, cellulose resin, (meth)acrylic resin, styrene resin, phenolic resin, polyurethane resin, polyamide resin, polyimide resin, polyamideimide resin, alkyd resin, etc.

[0073] When the conductive resin composition of the present invention contains an epoxy resin, the content ratio of the epoxy resin relative to all resin binders ((epoxy resin / all resin binders (polysiloxane resin + resin binder other than polysiloxane resin)) × 100) is preferably 25.0% by mass or less, more preferably 20.0% by mass or less, still more preferably 10% by mass or less, further preferably 5.0% by mass or less, and particularly preferably 0.0% by mass. By making the content ratio of the epoxy resin in the conductive resin composition relative to all resin binders within the above range, the moisture resistance of the conductive resin layer can be increased, and the change ratio of the moisture permeability amount with respect to the film thickness change can be reduced. Therefore, the design constraints of electronic components can be reduced, and since the formability is increased, the manufacturing efficiency can be improved.

[0074] In addition, when high adhesion of the conductive resin layer is required, the conductive resin composition of the present invention preferably contains an epoxy resin with a content ratio relative to all resin binders ((epoxy resin / all resin binders (polysiloxane resin + resin binder other than polysiloxane resin)) × 100) exceeding 0.0% by mass and 20.0% by mass or less, more preferably exceeding 0.0% by mass and 10.0% by mass or less, and further preferably exceeding 0.0% by mass and 5.0% by mass or less. By making the content ratio of the epoxy resin in the conductive resin composition relative to all resin binders within the above range, the adhesion of the conductive resin layer can be improved while maintaining relatively high moisture resistance of the conductive resin layer.

[0075] When the conductive resin composition of the present invention contains a butyral resin, the content ratio of the butyral resin to all resin binders ((butyral resin / all resin binders (polysiloxane resin + resin other than polysiloxane resin)) × 100) is preferably 20.0% by mass or less, more preferably 10.0% by mass or less, still more preferably 5.0% by mass or less, and particularly preferably 0.0% by mass. By making the content ratio of the butyral resin in the conductive resin composition within the above range with respect to all resin binders, the moisture resistance of the conductive resin layer can be improved, and the change ratio of the moisture permeability with respect to the film thickness change can be reduced. Therefore, the restrictions in design and manufacturing of electronic components can be reduced.

[0076] In the conductive resin composition of the present invention, from the viewpoints of high conductivity and adhesiveness of the obtained conductive resin layer and rheology suitable for the dipping method, the content of the resin binder (content of all resin binders (polysiloxane resin + resin other than polysiloxane resin)) is preferably 2.5 to 35.0 parts by mass, more preferably 5.0 to 25.0 parts by mass, still more preferably 7.0 to 23.0 parts by mass, and particularly preferably 11.0 to 20.0 parts by mass with respect to 100.0 parts by mass of the metal powder. In addition, when the conductive resin composition of the present invention is coated on the cathode body to be formed for a solid electrolytic capacitor to form a conductive resin layer, from the viewpoints of improving the conductivity and adhesiveness of the obtained conductive resin layer and rheology suitable for the dipping method, the content of the resin binder (content of all resin binders (polysiloxane resin + resin other than polysiloxane resin)) can be 2.5 to 35.0 parts by mass with respect to 100.0 parts by mass of the metal powder, preferably 5.0 to 25.0 parts by mass, more preferably 7.0 to 23.0 parts by mass, and particularly preferably 11.0 to 20.0 parts by mass. In addition, when the conductive resin composition of the present invention is coated on the laminate for a multilayer electronic component to form a conductive resin layer, from the viewpoints of improving the conductivity and adhesiveness of the obtained conductive resin layer and rheology suitable for the dipping method, the content of the resin binder (content of all resin binders (polysiloxane resin + resin other than polysiloxane resin)) is preferably 5.0 to 25.0 parts by mass, more preferably 7.0 to 23.0 parts by mass, and particularly preferably 11.0 to 20.0 parts by mass with respect to 100.0 parts by mass of the metal powder.

[0077] When the conductive resin composition of the present invention contains a curing agent, the content of the curing agent in the conductive resin composition is appropriately selected according to the content of the thermosetting resin in the conductive resin composition, and is usually 0.01 to 10.0% by mass.

[0078] The organic solvent involved in the conductive resin composition of the present invention is not particularly limited, and examples thereof include: terpineol, dihydroterpineol, dihydroterpineol acetate, sec-butyl alcohol, butyl carbitol, butyl carbitol acetate, benzyl alcohol, and the like.

[0079] In the conductive resin composition of the present invention, in addition to the above components, additives such as defoamers, plasticizers, dispersants, and rheology modifiers may be contained as needed. Examples of the plasticizer include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, bis(2-ethylhexyl) phthalate, di-n-octyl phthalate, butylbenzyl phthalate, dioctyl adipate, diisononyl adipate, dibutyl sebacate, diethyl sebacate, dioctyl sebacate, trimethyl phosphate, chlorinated paraffin, diisononyl cyclohexane-1,2-dicarboxylate (DINCH), and the like.

[0080] The conductive resin composition of the present invention is suitable for forming the cathode of a solid electrolytic capacitor and impregnation printing of a laminate for a multilayer electronic component. Examples of the rheology modifier include silica powder. When the conductive resin composition of the present invention contains silica powder, the content of silica powder in the conductive resin composition is preferably 0.0 to 3.0 parts by mass, particularly preferably 0.0 to 2.0 parts by mass, based on 100 parts by mass of the metal powder.

[0081] In the conductive resin composition of the present invention, the content of the organic solvent is appropriately selected according to the type and content of the metal powder, the type and content of the resin binder, the rheology required for the use, etc., and is preferably such that when a strain of 1% is applied to the conductive resin composition at an angular frequency of 1 Hz, the phase difference δ between the strain and the stress generated by the strain is within a given range, and the ratio of the viscosity of the conductive resin composition at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is within a given range.

[0082] In the conductive resin composition of the present invention, when a strain of 1% is applied to the conductive composition at an angular frequency of 1 Hz, the value of the phase difference δ between the strain and the stress generated by the strain is preferably in the range of 32 to 88°, more preferably in the range of 43 to 88°, more preferably in the range of 45 to 87°, more preferably in the range of 47 to 85°, particularly preferably in the range of 49 to 83°, and further preferably in the range of 51 to 81°. By making the value of the phase difference δ of the conductive resin composition within the above range, the formability when forming an electrode on an electrode forming body for an electronic component using the conductive resin composition is improved.

[0083] In particular, when forming an external electrode on a laminate for a multilayer electronic component by an impregnation method using the conductive resin composition of the present invention, the value of the phase difference δ is not particularly limited. From the viewpoint of improving formability, the lower limit of the value of the phase difference δ is preferably 45° or more, more preferably 47° or more, particularly preferably 49° or more, further preferably 50° or more, and further preferably 51° or more. In addition, from the viewpoint of improving formability, the upper limit of the value of the phase difference δ is preferably 87° or less, more preferably 85° or less, particularly preferably 83° or less, further preferably 81° or less, and further preferably 80° or less. It should be noted that the upper and lower limits of the phase difference δ can be arbitrarily combined. In addition, as the range of the value of the phase difference δ, from the viewpoint of improving formability, for example, it is preferably in the range of 45 to 87°, more preferably in the range of 47 to 85°, particularly preferably in the range of 49 to 83°, and further preferably in the range of 51 to 81°.

[0084] In addition, in particular, when forming a cathode on a cathode body for a solid electrolytic capacitor by an impregnation method using the conductive resin composition of the present invention, the value of the phase difference δ is not particularly limited. However, the lower limit of the value of the phase difference δ is preferably 32° or more, more preferably 37° or more, more preferably 45° or more, more preferably 47° or more, particularly preferably 49° or more, and further preferably 51° or more from the viewpoint of improving formability. In addition, the upper limit of the value of the phase difference δ is preferably 87° or less, more preferably 85° or less, particularly preferably 83° or less, further preferably 81° or less, and further preferably 80° or less from the viewpoint of improving formability. In addition, the upper and lower limits of the phase difference δ can be arbitrarily combined. In addition, as the range of the value of the phase difference δ, from the viewpoint of improving formability, for example, it is preferably in the range of 32 to 87°, more preferably in the range of 37 to 87°, more preferably in the range of 45 to 87°, more preferably in the range of 47 to 85°, particularly preferably in the range of 49 to 83°, and further preferably in the range of 51 to 81°.

[0085] The value of the phase difference δ of the conductive resin composition of the present invention is measured using a rheometer (manufactured by TA instrument, model: AR2000) under the conditions of 25°C, an angular frequency of 1 Hz, and a strain of 1% using parallel plates with a diameter of 40 mm. As a method for setting the phase difference δ of the conductive resin composition of the present invention within the above range, examples include adjusting the ratio (mass ratio) of spherical powder, flake powder, resin, and solvent in the conductive resin composition; and adding a rheology modifier.

[0086] From the viewpoint of improving the formability when forming an electrode on an electrode-forming body for an electronic component using a conductive resin composition, in the conductive resin composition of the present invention, when a strain of 1% is applied at an angular frequency of 1 Hz, the lower limit of the ratio of the viscosity at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is preferably 1.4 or more, more preferably 1.5 or more, still more preferably 2.0 or more, particularly preferably 2.5 or more. Further, when a strain of 1% is applied at an angular frequency of 1 Hz in the conductive composition, the upper limit of the ratio of the viscosity at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is preferably 60.0 or less, more preferably 30.0 or less, still more preferably 20.0 or less, particularly preferably 15.0 or less. Further, as the range of the ratio of the viscosity at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) when a strain of 1% is applied at an angular frequency of 1 Hz in the conductive resin composition of the present invention, from the viewpoint of improving the formability when forming an electrode on an electrode-forming body for an electronic component using the conductive resin composition, for example, the range of 1.4 to 60.0 is preferred, the range of 1.5 to 60.0 is more preferred, the range of 1.5 to 30.0 is still more preferred, the range of 2.0 to 20.0 is still more preferred, the range of 2.5 to 20.0 is still more preferred, the range of 2.5 to 15.0 is particularly preferred, and the range of 3.0 to 15.0 is more preferred.

[0087] In particular, when forming an external electrode on a laminate for a laminated electronic component by an impregnation method using the conductive composition of the present invention, the ratio of viscosities is not particularly limited, but from the viewpoint of improving the formability, the lower limit of the ratio of viscosities is preferably 1.5 or more, more preferably 2.0 or more, particularly preferably 2.5 or more. Further, the upper limit of the ratio of viscosities is preferably 20.0 or less, more preferably 15.0 or less, particularly preferably 12.0 or less. Further, as the range of the ratio of viscosities, from the viewpoint of improving the formability, for example, the range of 1.5 to 20.0 is preferably cited, the range of 2.0 to 20.0 is more preferably cited, the range of 2.5 to 15.0 is particularly preferably cited, and the range of 2.5 to 12.0 is further preferably cited.

[0088] In addition, particularly when forming a cathode on a cathode body for a solid electrolytic capacitor using the conductive composition of the present invention by an impregnation method, the ratio of viscosities is not particularly limited. From the viewpoint of improved formability, the lower limit of the ratio of viscosities is preferably 1.5 or more, more preferably 2.0 or more, particularly preferably 2.5 or more. In addition, the upper limit of the ratio of viscosities is preferably 60.0 or less, more preferably 50.0 or less, more preferably 35.0 or less, more preferably 20.0 or less, particularly preferably 15.0 or less. In addition, as the range of the ratio of viscosities, from the viewpoint of improved formability, for example, a range of preferably 1.5 to 60.0, more preferably 2.0 to 50.0, more preferably 2.0 to 35.0, more preferably 2.0 to 20.0, particularly preferably 2.5 to 15.0 can be cited.

[0089] Regarding the ratio of viscosities of the conductive resin composition of the present invention, the viscosity at a shear rate of 0.4 (1 / s) is calculated relative to the viscosity at a shear rate of 40 (1 / s) by measuring viscosities at 25 °C under the conditions of a shear rate of 0.4 (1 / s) and a shear rate of 40 (1 / s) using a rotational viscometer (manufactured by BROOKFIELD, model: HADV-II+Pro). As a method for making the ratio of viscosities of the present invention within the above range, adjusting the ratio (mass ratio) of spherical powder, flaky powder, resin, and solvent in the conductive resin composition; adding a rheology modifier can be cited.

[0090] The moisture permeability amount of the conductive resin composition of the present invention determined by the following moisture permeability amount measurement test is 80.0 mg or less, preferably 40.0 mg or less, more preferably 20.0 mg or less. By making the moisture permeability amount determined by the moisture permeability amount measurement test within the above range, when forming a conductive resin layer using the conductive resin composition of the present invention, an electronic component with excellent moisture resistance can be obtained.

[0091] <Moisture Permeability Amount Measurement Test>

[0092] The conductive resin composition is cast on a PET film to a thickness of 250 μm and cured under the conditions of 200 °C for 60 minutes. The obtained cured film is cut into a circle with a diameter of 7.5 mm and fixed with an adhesive in a manner that covers a 5 ml glass bottle containing 2 g of silica gel. In a state where the cured film is not in contact with pure water, the glass bottle is placed in a 750 ml container containing 100 ml of pure water and sealed, and then left standing in a dryer set at 65 °C for 15 hours. Then, the moisture permeability amount is calculated by the following formula (1):

[0093] Moisture permeability amount (weight increase amount) = weight of the glass bottle after being placed in the dryer - weight of the glass bottle before being placed in the dryer (1).

[0094] In the conductive resin composition of the present invention, the conductive resin composition of the first embodiment of the present invention described below has high formability when forming an electrode using the conductive resin composition on an electrode forming body for an electronic component, and particularly has high formability when forming a conductive resin layer by an impregnation method on a laminate for a stacked electronic component.

[0095] The conductive resin composition of the first embodiment of the present invention is a conductive resin composition containing a metal powder, a resin binder, and an organic solvent, wherein

[0096] when the metal powder is set to 100.0 parts by mass, the content of the resin binder is 5.0 to 25.0 parts by mass,

[0097] 80.0 mass% or more of the resin binder is a polysiloxane resin,

[0098] 20.0 mass% or more of the metal powder is a flaky metal powder,

[0099] when a strain of 1% is applied to the conductive resin composition at an angular frequency of 1 Hz, the value of the phase difference δ between the strain and the stress generated by the strain is in the range of 45 to 87°,

[0100] the ratio of the viscosity of the conductive resin composition at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is in the range of 1.5 to 20.0.

[0101] The metal powder, flaky metal powder, spherical metal powder, resin binder, polysiloxane resin, thermosetting polysiloxane resin, curing agent, thermoplastic polysiloxane resin, resin binder other than polysiloxane resin, epoxy resin, butyral resin, organic solvent, additives such as defoaming agent, plasticizer, dispersant, and rheology modifier used as needed in the conductive resin composition of the first embodiment of the present invention are the same as those in the metal powder, flaky metal powder, spherical metal powder, resin binder, polysiloxane resin, thermosetting polysiloxane resin, curing agent, thermoplastic polysiloxane resin, resin binder other than polysiloxane resin, epoxy resin, butyral resin, organic solvent, additives such as defoaming agent, plasticizer, dispersant, and rheology modifier used as needed in the conductive resin composition of the present invention.

[0102] In the conductive resin composition according to the first aspect of the present invention, 20.0 mass% or more of all the metal powders is flaky metal powder. The content ratio of the flaky metal powder relative to the total metal powders is 20.0 to 100.0 mass%, preferably 40.0 to 100.0 mass%, and particularly preferably 60.0 to 100.0 mass%. By setting the content ratio of the flaky metal powder relative to the total metal powders within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are increased.

[0103] In the conductive resin composition according to the first aspect of the present invention, 80.0 mass% or more of all the resin binders is polysiloxane resin. In the conductive resin composition according to the first aspect of the present invention, the content ratio of the polysiloxane resin relative to all the resin binders is preferably 80.0 to 100.0 mass%, more preferably 90.0 to 100.0 mass%, and particularly preferably 95.0 to 100.0 mass%. By containing the polysiloxane resin in the conductive resin composition within the above range, the moisture resistance of the conductive resin layer can be increased, the change ratio of the moisture permeability with respect to the change in the film thickness can be decreased, the design constraints can be reduced, the formability can be improved, and thus the manufacturing efficiency can be increased.

[0104] When the conductive resin composition according to the first aspect of the present invention contains an epoxy resin, the content ratio of the epoxy resin relative to all the resin binders (epoxy resin / all resin binders (polysiloxane resin + resin other than polysiloxane resin) × 100) is preferably 25.0 mass% or less, more preferably 20.0 mass% or less, still more preferably 10 mass% or less, further preferably 5.0 mass% or less, and particularly preferably 0.0 mass%. By setting the content ratio of the epoxy resin in the conductive resin composition relative to all the resin binders within the above range, the moisture resistance of the conductive resin layer can be increased, and the change ratio of the moisture permeation amount with respect to the change in the film thickness can be decreased. Therefore, the design constraints of the electronic component can be reduced, and the manufacturing efficiency can be increased due to the improved formability.

[0105] In addition, when high adhesion of the conductive resin layer is required, in the conductive resin composition according to the first aspect of the present invention, it is preferably to contain an epoxy resin with a content ratio of the epoxy resin relative to all the resin binders (epoxy resin / all resin binders (polysiloxane resin + resin other than polysiloxane resin) × 100) exceeding 0.0 mass% and 20.0 mass% or less, more preferably exceeding 0.0 mass% and 10 mass% or less, and further preferably exceeding 0.0 mass% and 5.0 mass% or less. By setting the content ratio of the epoxy resin in the conductive resin composition relative to all the resin binders within the above range, the adhesion of the conductive resin layer can be improved while maintaining the moisture resistance of the high-conductivity resin layer.

[0106] When the conductive resin composition of the first aspect of the present invention contains a butyral resin, the content ratio of the butyral resin to all resin binders (butyral resin / all resin binders (polysiloxane resin + resin other than polysiloxane resin) × 100) is preferably 20.0% by mass or less, more preferably 10.0% by mass or less, further preferably 5.0% by mass or less, and particularly preferably 0.0% by mass. By making the content ratio of the butyral resin in the conductive resin composition within the above range, the moisture resistance of the conductive resin layer is improved, and the change ratio of the moisture permeability amount with respect to the film thickness change can be reduced. Therefore, the restrictions in design and manufacturing of electronic components can be reduced.

[0107] In the conductive resin composition of the first aspect of the present invention, the content of the resin binder (the content of all resin binders (polysiloxane resin + resin other than polysiloxane resin)) is 5.0 to 25.0 parts by mass, preferably 7.0 to 23.0 parts by mass, and particularly preferably 11.0 to 20.0 parts by mass with respect to 100.0 parts by mass of the metal powder. By making the content of the resin component in the conductive resin composition within the above range, the conductivity and adhesiveness of the obtained conductive resin layer are improved, and the rheological properties suitable for the dipping method are achieved.

[0108] When the conductive resin composition of the first aspect of the present invention contains a thermosetting resin as the polysiloxane resin, a curing agent may be contained. When the conductive resin composition of the first aspect of the present invention contains a curing agent, the content of the curing agent in the conductive resin composition is appropriately selected according to the content of the thermosetting resin in the conductive resin composition, and is usually 0.01 to 10.0% by mass.

[0109] In the conductive resin composition of the first aspect of the present invention, in addition to the above components, additives such as an antifoaming agent, a plasticizer, a dispersant, and a rheology modifier may be contained as needed. Examples of the plasticizer include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, di-n-octyl phthalate, butyl benzyl phthalate, dioctyl adipate, diisononyl adipate, dibutyl sebacate, diethyl sebacate, dioctyl sebacate, trimethyl phosphate, chlorinated paraffin, and diisononyl cyclohexane-1,2-dicarboxylate (DINCH). Examples of the rheology modifier include silica powder. When the conductive resin composition of the present invention contains silica powder, the content of the silica powder in the conductive resin composition of the present invention is preferably 0.0 to 3.0 parts by mass, and particularly preferably 0.0 to 2.0 parts by mass with respect to 100 parts by mass of the metal powder.

[0110] In the conductive resin composition according to the first aspect of the present invention, when a strain of 1% is applied at an angular frequency of 1 Hz, the value of the phase difference δ between the strain and the stress generated by the strain is in the range of 45 to 87°, preferably in the range of 47 to 85°, particularly preferably in the range of 49 to 83°, and more preferably in the range of 51 to 81°. By setting the value of the phase difference δ within the above range, the formability is improved when forming an electrode on an electrode forming body for an electronic component using the conductive resin composition.

[0111] The ratio of the viscosity of the conductive resin composition according to the first aspect of the present invention at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is in the range of 1.5 to 20.0, preferably in the range of 2.0 to 20.0, and more preferably in the range of 2.5 to 15.0. By setting the viscosity ratio within the above range, the formability is improved when forming an electrode on an electrode forming body for an electronic component using the conductive resin composition, and particularly the formability is improved when forming a conductive resin layer by an impregnation method on a laminate for a multilayer electronic component.

[0112] The conductive resin composition of the present invention (including the conductive resin composition according to the first aspect of the present invention) is applicable in the manufacture of electronic components as a conductive resin composition for forming an electrode on an electrode forming body on which an electrode is to be formed (hereinafter also referred to as an electrode forming body for an electronic component). Further, the conductive resin composition of the present invention (including the conductive resin composition according to the first aspect of the present invention) is particularly applicable as a conductive resin composition for forming an external electrode of a laminate for a multilayer electronic component.

[0113] The method for manufacturing an electronic component of the present invention is a method for manufacturing an electronic component in which an electrode is formed on an electronic component using the conductive resin composition of the present invention (including the conductive resin composition according to the first aspect of the present invention), and includes: a preparation step of preparing an electrode forming body for an electronic component; and an electrode forming step of forming an electrode on an outer surface of the electrode forming body for an electronic component. In the electrode forming step, an electrode is formed by forming a conductive resin layer on the electrode forming body for an electronic component using the conductive resin composition of the present invention.

[0114] The method for manufacturing an electronic component of the present invention includes: a preparation step of preparing an electrode forming body for an electronic component; and

[0115] an electrode forming step of forming an electrode on an outer surface of the electrode forming body for an electronic component,

[0116] In this electrode forming step, a conductive resin layer is formed on the electrode forming body for an electronic component using a conductive resin composition. The conductive resin composition contains metal powder, a resin binder, and an organic solvent. In the metal powder, 20.0 mass% or more is flaky metal powder, and in the resin binder, 70.0 mass% or more is a polysiloxane resin.

[0117] The preparation step is a step of preparing an electrode forming body for an electronic component. An electrode forming body for an electronic component refers to an object on which an electrode is formed in the manufacturing process of an electronic component. Examples of the electrode forming body for an electronic component include a laminate for a multilayer electronic component including a plurality of ceramic layers and a plurality of internal electrode layers, a cathode forming body for a solid electrolytic capacitor including an anode and a dielectric layer formed on the surface of the anode, and an electrode forming body for a chip resistor having end electrodes.

[0118] The laminate for a multilayer electronic component includes a plurality of ceramic layers and a plurality of internal electrode layers. In the laminate for a multilayer electronic component, adjacent ceramic layers are connected to each other through the internal electrode layer interposed therebetween. Examples of the laminate for a multilayer electronic component include a laminate for a multilayer ceramic capacitor, a laminate for a multilayer ceramic inductor, and a laminate for a piezoelectric actuator.

[0119] Examples of the forming material of the ceramic layer constituting the laminate for a multilayer electronic component include barium titanate, strontium titanate, calcium titanate, barium zirconate, strontium zirconate, calcium zirconate, strontium calcium zirconate, etc.

[0120] Examples of the forming material of the internal electrode layer constituting the laminate for a multilayer electronic component include any one of nickel, palladium, silver, copper, gold, etc., or an alloy containing one or more of them (for example, an alloy of silver and palladium, etc.).

[0121] The cathode forming body for a solid electrolytic capacitor includes an anode and a dielectric layer formed on the surface of the anode. Examples of the combination of the forming materials of the anode and the dielectric layer include tantalum and tantalum pentoxide, aluminum and aluminum oxide, niobium and niobium pentoxide, etc.

[0122] The electrode formation step is a step of forming an electrode on the outer surface of the electrode formation body for an electronic component. It should be noted that in the present invention, forming a conductive resin layer on the electrode formation body for an electronic component includes both the case of directly forming a conductive resin layer on the surface of the electrode formation body for an electronic component and the case of first forming other layers or films (such as a metal layer, a conductor layer, etc.) on the electrode formation body for an electronic component and then forming a conductive resin layer on its surface. Therefore, in the electronic component obtained by the manufacturing method of the electronic component of the present invention, there are both the case where a conductive resin layer is directly formed on the surface of the electrode formation body for an electronic component and the case where a conductive resin layer is formed in a state where other layers or films (such as a metal layer, a conductor layer, etc.) are interposed between the electrode formation bodies for an electronic component.

[0123] In the electrode formation step, the position, method, thickness of the electrode, number of electrodes, type of metal constituting the electrode, shape of the metal powder used in the electrode formation, etc. can be appropriately selected according to the electronic component to be manufactured.

[0124] In the electrode formation step, the conductive resin composition of the present invention is used to form a conductive resin layer on the electrode formation body for an electronic component.

[0125] In the electrode formation step, by coating the conductive resin composition of the present invention on the electrode formation body for an electronic component, a layer of the conductive resin composition of the present invention is formed at a given position on the electrode formation body for an electronic component, and then, by curing the conductive resin composition of the present invention, a conductive resin layer is formed.

[0126] In the electrode forming process, a conductive resin layer can be directly formed on the surface of the electrode forming body for electronic components by directly coating the conductive resin composition of the present invention on the surface of the electrode forming body for electronic components. In addition, in the electrode forming process, before forming a conductive resin layer on the electrode forming body for electronic components, appropriate processes can be provided according to the type of electronic components. For example, in the case of a multilayer electronic component, in the electrode forming process, after forming a metal layer at a given position on the electrode forming body for electronic components, a layer of the conductive resin composition of the present invention is formed at the given position on the electrode forming body for electronic components by coating the conductive resin composition of the present invention on the surface of the metal layer, and then, by curing the conductive resin composition of the present invention, a conductive resin layer is formed on the surface of the metal layer. In addition, for example, in the case of a solid electrolytic capacitor, in the electrode forming process, after forming a conductive layer composed of a carbon layer at a given position on the cathode body to be formed for the solid electrolytic capacitor, a layer of the conductive resin composition of the present invention is formed at the given position on the electrode forming body for electronic components by coating the conductive resin composition of the present invention on the surface of the conductive layer, and then, by curing the conductive resin composition of the present invention, a conductive resin layer is formed on the surface of the conductive layer. In addition, in the electrode forming process, after forming a conductive resin layer on the electrode forming body for electronic components, appropriate processes can be provided according to the type of electronic components. For example, in the case of a multilayer electronic component, in the electrode forming process, after forming a conductive resin layer at a given position on the electrode forming body for electronic components, a plating layer is formed on the surface of the conductive resin layer.

[0127] In the electrode forming process, an electrode can be formed by forming a conductive resin layer on the electrode forming body for electronic components. That is, in this method, the electrode is composed only of the conductive resin layer.

[0128] In the electrode forming process, when forming a conductive resin layer on the electrode forming body for electronic components using the conductive resin composition of the present invention, the conductive resin composition of the present invention can be coated on the electrode forming body for electronic components by an impregnation method, and a layer of the conductive resin composition of the present invention is formed at a given position on the electrode forming body for electronic components. Since the formability of the conductive resin composition of the present invention is excellent, a layer of the conductive resin composition of the present invention can be rapidly formed at a given position by the impregnation method. Therefore, according to the conductive resin composition of the present invention, by coating the conductive resin composition of the present invention on the electrode forming body for electronic components by the impregnation method, the manufacturing efficiency can be improved.

[0129] The first method of the electrode formation process (hereinafter, also referred to as the electrode formation process (1)) is the electrode formation process in the case where the electrode formation body for an electronic component is a laminated body for a laminated electronic component composed of a ceramic layer and an internal electrode layer. Moreover, the electrode formation process (1) at least includes: a conductive resin layer formation process (1) of forming a conductive resin layer on the outer surface of the laminated body for a laminated electronic component using the conductive resin composition of the present invention. As the electrode formation process (1), as long as it has the conductive resin layer formation process (1) of forming a conductive resin layer on the outer surface of the laminated body for a laminated electronic component using the conductive resin composition of the present invention, there is no particular limitation. For example, an electrode formation process (1A) including at least a metal layer formation process, a conductive resin layer formation process (1A), and a plating layer formation process can be cited.

[0130] The metal layer formation process is a process of forming a metal layer electrically connected to the internal electrode layer on the outer surface of the laminated body for a laminated electronic component. As the metal for forming the metal layer, at least one of Cu, Ag, Pd, Ni, Sn, Al, Au, and Pt, or an alloy containing one or more of them can be cited. As the method for forming the metal layer, there is no particular limitation. For example, an immersion method, a plating method, a roll coating method, a screen printing method, and a sputtering method can be cited. The thickness, shape, position, number, etc. of the metal layer can be appropriately selected.

[0131] The conductive resin layer formation process (1A) is a process of forming a conductive resin layer on the surface of the metal layer formed by performing the metal layer formation process using the conductive resin composition of the present invention.

[0132] In the conductive resin layer formation process (1A), a layer of the conductive resin composition of the present invention is formed on the surface of the metal layer by coating the conductive resin composition of the present invention on the surface of the metal layer formed by performing the metal layer formation process. Then, the conductive resin composition of the present invention is cured to form a conductive resin layer. As the method for forming the layer of the conductive resin composition of the present invention, there is no particular limitation. For example, an immersion method, a screen printing method, and a roll coating method can be cited. Among them, the immersion method is preferred. The thickness, shape, position, number, etc. of the layer of the conductive resin composition of the present invention can be appropriately selected.

[0133] The plating layer formation process is a process of forming a plating layer on the surface of the conductive resin layer. As the metal for forming the plating layer, at least one of Ni, Cu, Sn, Ag, and Au, or an alloy containing one or more of them can be cited. As the method for forming the plating layer, there is no particular limitation. For example, electroplating and electroless plating can be cited. The thickness, shape, position, number, etc. of the plating layer can be appropriately selected.

[0134] The second method of the electrode forming process (hereinafter, also referred to as the electrode forming process (2)) is the electrode forming process when the electrode forming body for electronic components is the cathode body to be formed for a solid electrolytic capacitor. And the electrode forming process (2) at least has a conductive resin layer forming process (2) of forming a conductive resin layer on the outer surface of the cathode body to be formed for a solid electrolytic capacitor using the conductive resin composition of the present invention. As the electrode forming process (2), as long as it has a conductive resin layer forming process (2) of forming a conductive resin layer on the outer surface of the cathode body to be formed for a solid electrolytic capacitor using the conductive resin composition of the present invention, there is no particular limitation. For example, an electrode forming process (2A) including at least a solid electrolyte layer forming process, a carbon layer forming process, and a conductive resin layer forming process (2A) can be cited.

[0135] The solid electrolyte layer forming process is a process of forming a solid electrolyte layer on the outer surface of the cathode body to be formed for a solid electrolytic capacitor. As a method of forming the solid electrolyte layer, there is no particular limitation, and it can be formed using a known solid electrolyte manufactured by a chemical method. As the solid electrolyte, for example, conductive polymers such as polypyrrole, polyaniline, polythiophene, and polyacetylene can be cited.

[0136] The carbon layer forming process is a process of forming a carbon layer on the solid electrolyte layer. As a method of forming the carbon layer, there is no particular limitation. For example, a method of coating a carbon paste containing a resin, a solvent, and carbon powder on the solid electrolyte layer by an impregnation method and then drying and / or curing it can be cited. The carbon powder is not particularly limited, and graphite powder is preferred.

[0137] The conductive resin layer forming process (2A) is a process of forming a conductive resin layer on the carbon layer using a conductive resin composition containing a polysiloxane resin. As a method of forming the conductive resin layer, there is no particular limitation. For example, a method of coating a conductive resin composition containing a polysiloxane resin by an impregnation method, a screen printing method, a roll coating method, etc., and then curing the conductive resin composition containing a polysiloxane resin can be cited.

[0138] As another method of the electrode formation process, there can be cited the electrode formation process (3) in the case where the electrode formation body for an electronic component is an electrode formation body for a chip resistor having end face electrodes. The electrode formation process (3) at least includes a process of forming a conductive resin layer on the end face electrodes. As a method of forming the conductive resin layer, there is no particular limitation. For example, there can be cited a method of coating a conductive resin composition containing a polysiloxane resin by an impregnation method, a screen printing method, a roll coating method, etc., and then curing the conductive resin composition containing the polysiloxane resin. The electrode formation body for a chip resistor having end face electrodes, for example, includes: an insulating substrate, a pair of upper surface electrodes formed on the insulating substrate, a resistor body formed between the pair of upper surface electrodes, a protective layer formed so as to cover a part of the pair of upper surface electrodes and the resistor body, and end face electrodes formed on the end face of the insulating substrate.

[0139] As another method of the electrode formation process, there can be cited the electrode formation process (4) in the case where the electrode formation body for an electronic component is a substrate. The electrode formation process (4) at least includes a process of forming a conductive resin layer on the substrate. As a method of forming the conductive resin layer, there is no particular limitation. For example, there can be cited a method of coating a conductive resin composition containing a polysiloxane resin by screen printing, inkjet printing or dispenser printing, and then curing the conductive resin composition containing the polysiloxane resin. As the substrate, for example, there can be cited an alumina substrate, a glass epoxy substrate, a phenolic paper substrate, a paper epoxy substrate.

[0140] As another method of the electrode formation process, there can be cited the electrode formation process (5) in the case where the electrode formation body for an electronic component is a thin film. The electrode formation process (5) at least includes a process of forming a conductive resin layer on the thin film. As a method of forming the conductive resin layer, there is no particular limitation. For example, there can be cited a method of coating a conductive resin composition containing a polysiloxane resin by screen printing, inkjet printing or dispenser printing, and then curing the conductive resin composition containing the polysiloxane resin. As the thin film, for example, there can be cited a polyimide film, a PET film.

[0141] The resistivity of the conductive resin layer obtained by using the conductive resin composition of the present invention is preferably 1000 μΩ·cm or less, more preferably 500 μΩ·cm or less, and particularly preferably 200 μΩ·cm or less.

[0142] The elongation of the conductive resin layer obtained by using the conductive resin composition of the present invention is preferably 0.2% or more, and particularly preferably 0.3% or more. By forming a conductive resin layer with an elongation within the above range between the metal layer of the external electrode of the laminated electronic component and the plating layer, cracks and interface peeling are not easily generated at the connection part between the substrate and the electronic component, and cracks are not easily generated in the electronic component itself, so the impact resistance of the electronic component is improved. Therefore, by using the conductive resin composition of the present invention to form between the metal layer of the external electrode of the laminated electronic component and the plating layer, the impact resistance of the electronic component can be improved. The elongation of the conductive resin layer is determined by casting a conductive resin composition with a thickness of 250 μm on a PET film, curing it at 200° C. for 60 minutes, cutting the resulting cured film into a rectangle with a width of 5 mm, and measuring the length of the coating film when a tensile load of 9.8 N is applied in the long axis direction of the cured film using a viscoelasticity measuring device (manufactured by HITACHI HIGH-TECH SCIENCE, model: DMA-7100), and calculating the ratio of the elongated length when the load is applied to the length of 10 mm before the load is applied.

[0143] The adhesion strength of the conductive resin layer obtained using the conductive resin composition of the present invention is preferably 0.2MPa or more, more preferably 0.3MPa or more, and particularly preferably 0.4MPa or more. By making the adhesion strength of the conductive resin layer within the range, the impact resistance of the electronic component can be improved. The adhesion strength of the conductive resin layer is to cast the conductive resin composition on a glass slide substrate with a thickness of 50μm, place an aluminum cylinder with a diameter of 3mm, and cure it under the conditions of 200°C and 60 minutes, and use an adhesion tester (made by Nishijin Trading Co., Ltd., model: SS-30WD) to stretch in the vertical direction at a speed of 0.5mm / s, and measure the value at the time of fracture.

[0144] Since the conductive resin composition of the present invention uses a polysiloxane resin as all or part of the resin binder, the moisture resistance of the resulting conductive resin layer is higher than that of a conductive resin composition using an epoxy resin as the main component of the resin binder, and the heat resistance of the resulting conductive resin layer is higher than that of a conductive resin composition containing a large amount of butyral resin as the resin binder.

[0145] In the case of most epoxy resins, if the epoxy resin is used alone, the cured product becomes too hard, so it does not meet requirements such as stress relaxation, and it is difficult to endow a conductive resin composition mainly composed of an epoxy resin as a resin binder with suitable physical properties. Therefore, in a conductive resin composition mainly composed of an epoxy resin as a resin binder, in order to impart flexibility, a butyral resin needs to be contained. However, the heat resistance of the butyral resin is often low, and in the case of a manufacturing method of a conductive resin composition using an epoxy resin as the main component of the resin binder and containing butyral, it is difficult to improve the heat resistance of the obtained conductive resin layer. In contrast, in the conductive resin composition of the present invention, a polysiloxane resin is used as the resin binder, and since a given amount of the polysiloxane resin is contained, the obtained conductive resin layer easily meets requirements such as stress relaxation. Therefore, according to the conductive resin composition of the present invention, a conductive resin layer with higher heat resistance can be obtained compared to a conductive resin composition mainly composed of an epoxy resin as a resin binder and containing butyral.

[0146] In addition, the conductive resin layer obtained by using the conductive resin composition of the present invention has a smaller change ratio of the moisture permeation amount with respect to the change in the film thickness compared to the conductive resin layer obtained from a conductive resin composition having an epoxy resin component as the main component of the resin binder and containing butyral.

[0147] The film thickness of the conductive resin layer formed on the object to be formed with the conductive resin layer varies depending on the type of electronic component. And when the film thickness becomes thinner, the moisture permeation amount increases, so it is necessary to increase the resin ratio in the conductive resin layer, etc. to compensate for the increased part of the moisture permeation amount. At this time, the larger the change ratio of the moisture permeation amount with respect to the change in the film thickness, the larger the increase amount of the moisture permeation amount, so more countermeasures for compensating the increased part of the moisture permeation amount are required. Therefore, when the change ratio of the moisture permeation amount with respect to the change in the film thickness of the obtained conductive resin layer is large, that is, when using a conductive resin composition mainly composed of an epoxy resin as a resin binder and containing butyral, the design constraints of the electronic component become larger, and consequently, the manufacturing constraints when forming the conductive resin layer become larger. In contrast, when the change ratio of the moisture permeation amount with respect to the change in the film thickness of the obtained conductive resin layer is small, that is, when using the conductive resin composition of the present invention, the design constraints of the electronic component are small, and thus the manufacturing constraints when forming the conductive resin layer associated therewith can be reduced.

[0148] Hereinafter, the present invention will be described based on specific experimental examples, but the present invention is not limited thereto.

[0149] Examples

[0150] <Manufacture of silver powder>

[0151] First, based on the spray pyrolysis method described in Japanese Patent Publication No. 63-31522, silver powders 1 and 2 described in Table 1 were prepared. That is, for silver powder 1, an aqueous solution in which a silver salt was dissolved was subjected to spray pyrolysis, and the collected silver powder was classified to adjust the D 50 value.

[0152] It should be noted that for the obtained silver powder, a laser diffraction particle size distribution measuring device was used to determine the 50% value (D 50 ) of the cumulative fraction on a volume basis. In addition, the specific surface area was measured by the BET method.

[0153] <Method for manufacturing flaky silver powder>

[0154] Spherical silver powder was manufactured by the above method. The obtained spherical silver powder was pulverized using stearic acid as a lubricant with a ball mill to manufacture flaky silver powder. The particle diameter and aspect ratio of 50 silver powders arbitrarily selected in the SEM (scanning electron microscope) image observation were measured, and their average values were obtained. In addition, the specific surface area was measured by the BET method.

[0155] <Silver-coated copper flake powder>

[0156] Silver-coated copper powder in which silver was coated in a proportion of 10 parts by mass with respect to 90 parts by mass of spherical copper powder (manufactured by Mitsui Mining & Smelting Co., Ltd., model: MA-CO3K) was manufactured. The obtained silver-coated copper powder was pulverized using palmitic acid as a lubricant with a ball mill to manufacture flaky silver-coated copper powder. The particle diameter and aspect ratio of 50 silver powders arbitrarily selected in the SEM image observation were measured, and their average values were obtained. In addition, the specific surface area was measured by the BET method.

[0157] <Preparation of conductive resin composition>

[0158] A conductive resin composition was prepared by mixing a metal powder, a polysiloxane resin, and an epoxy resin in the mixing ratios shown in Table 1 and Table 2.

[0159] · Metal powder 1

[0160] Spherical silver powder, D 50 : 2.3 μm, specific surface area: 0.5 m 2 / g

[0161] · Metal powder 2

[0162] Flaky silver powder, aspect ratio: 30, number average particle diameter: 6.0 μm, specific surface area: 1.0 m 2 / g

[0163] · Metal powder 3

[0164] Flaky silver-coated copper powder, aspect ratio: 20, D 50: 8.0 μm, specific surface area: 1.5 m 2 / g

[0165] · Polysiloxane resin 1

[0166] Thermosetting polysiloxane resin, self-curing type, manufactured by Shin-Etsu Chemical Co., Ltd., model: ES-1001N, reactive functional groups: hydroxyl group, epoxy group

[0167] · Epoxy resin 1

[0168] Thermosetting epoxy resin, manufactured by DIC Corporation, model: EXA4816

[0169] · Butyral resin 1

[0170] Butyral resin, manufactured by Sekisui Chemical Co., Ltd., model: KS-10

[0171] · Silica powder 1

[0172] Fumed silica, manufactured by TOKUYAMA Corporation, model: HM-20L

[0173] It should be noted that the amount of resin in the following table refers to the amount of the resin itself excluding the solvent.

[0174] (Examples 1 - 8)

[0175] 135 parts by mass of polysiloxane resin 1 as the resin solid component was mixed with 165 parts by mass of benzyl alcohol (manufactured by GODO Co., Ltd.), and solvent replacement was carried out under the conditions of 130 °C, 30 Pa, and 1 hour to obtain a resin solution. The obtained resin solution, metal powder 1, and metal powder 2 were mixed in the proportions described in Table 1, and then kneaded using a three-roll mill (manufactured by Inoue Seisakusho) to obtain a paste-like composition.

[0176] The obtained paste-like composition was diluted with benzyl alcohol to adjust the viscosity to 30 Pa·s at 25 °C and a shear rate of 4 (1 / s), and then the following evaluations were carried out. The results are shown in Table 1.

[0177] (Examples 9 - 13, Comparative Examples 1 - 4)

[0178] 135 parts by mass of polysiloxane resin 1 as the resin solid component was mixed with 165 parts by mass of benzyl alcohol (manufactured by GODO Co., Ltd.), and solvent replacement was carried out under the conditions of 130 °C, 30 Pa, and 1 hour to obtain a resin solution. The obtained resin solution, metal powder 3, and epoxy resin 1 were mixed in the proportions described in Table 2, and then kneaded using a three-roll mill (manufactured by Inoue Seisakusho) to obtain a paste-like composition.

[0179] The obtained paste composition was diluted with benzyl alcohol to adjust its viscosity to 30 Pa·s at 25°C and a shear rate of 4 (1 / s), and then the following evaluations were carried out. The results are shown in Table 2.

[0180] <Performance Evaluation>

[0181] (Viscosity Ratio)

[0182] The viscosities of the conductive resin composition were measured at 25°C using a rotational viscometer (manufactured by BROOKFIELD, model: HADV-II+Pro) under the conditions of a shear rate of 0.4 (1 / s) and a shear rate of 40 (1 / s). The ratio of the viscosity at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) was calculated as the viscosity ratio.

[0183] (Phase Difference δ)

[0184] Using a rheometer (manufactured by TA instrument, model: AR2000), measurements were carried out at 25°C, an angular frequency of 1 Hz, and a strain of 1% using parallel plates with a diameter of 40 mm to obtain the value of the phase difference δ of the conductive resin composition.

[0185] (Moisture Permeation Amount)

[0186] The conductive resin composition was cast on a PET film with a thickness of 250 μm and cured at 200°C for 60 minutes to obtain a cured film. The obtained cured film was cut into a circle with a diameter of 7.5 mm and fixed with an adhesive in a manner that covered a 5 ml glass bottle containing 2 g of silica gel. Then, the glass bottle was placed in a 750 ml container containing 100 ml of purified water in a sealed state such that the cured film did not contact the purified water, and left standing in a dryer set at 65°C for 15 hours. The weights of the glass bottle before and after being placed in the dryer were measured, and the increased weight was taken as the moisture permeation amount. If the moisture permeation amount exceeds 160 mg, it is "Score: 1, Unqualified, Not Usable, Extremely Low Moisture Resistance"; if the moisture permeation amount exceeds 80.0 mg and is 160 mg or less, it is "Score: 2, Unqualified, Not Usable, Low Moisture Resistance"; if the moisture permeation amount exceeds 40.0 mg and is 80.0 mg or less, it is "Score 3: Qualified, Usable"; if the moisture permeation amount exceeds 20.0 mg and is 40.0 mg or less, it is "Score 4: Qualified, Usable, High Moisture Resistance"; if the moisture permeation amount is 20.0 mg or less, it is "Score 5: Qualified, Usable, Extremely High Moisture Resistance".

[0187] (Elongation)

[0188] The conductive resin composition was cast on a PET film with a thickness of 250 μm and cured at 200 °C for 60 minutes to obtain a cured film. The obtained cured film was cut into rectangles with a width of 5 mm, and a viscoelasticity measuring device (manufactured by HITACHI HIGH-TECH SCIENCE CORPORATION, model: DMA-7100) was used to measure the length of the coating film when a tensile load of 9.8 N was applied in the long axis direction. The ratio of the length stretched when the load was applied to the length of 10 mm before the load was applied was calculated as the elongation rate.

[0189] (Resistivity)

[0190] The conductive resin composition was cast on a glass slide substrate with a width of 1 cm, a length of 5 cm, and a thickness of 50 μm, and cured at 200 °C for 60 minutes to obtain a cured film. Using a digital multimeter (manufactured by Keithley Instruments, KEITHLEY2002), the resistance of the surface of the cured film was measured by the four-terminal method, and the resistivity was calculated based on the obtained value and the sample thickness.

[0191] (Adhesion strength)

[0192] The conductive resin composition was cast on a glass slide substrate with a thickness of 50 μm, and an aluminum cylinder with a diameter of 3 mm was placed, and it was cured at 200 °C for 60 minutes. Using an adhesion tester (manufactured by NISHIN SHOSHI CO., LTD., model: SS-30WD), it was stretched vertically at a speed of 0.5 mm / s, and the value at break was measured.

[0193] [Table 1]

[0194]

[0195] [Table 2]

[0196]

[0197] * Content ratio of polysiloxane resin: The content ratio (%) of the polysiloxane resin relative to all resin components in the conductive resin composition containing the polysiloxane resin ((polysiloxane resin / all resin components (polysiloxane resin + resin other than polysiloxane resin)) × 100)

[0198] From the results in Table 1, it can be seen that in Examples 1 to 8, a conductive resin layer with a low moisture permeability was obtained, and it had the adhesion strength required for the conductive resin layer. Therefore, an electronic component with high moisture resistance can be manufactured.

[0199] In addition, according to the results in Table 2, in Examples 9 to 13, a conductive resin layer with a low moisture permeability was obtained and had the adhesion strength required for the conductive resin layer. Therefore, by using a conductive resin composition containing a polysiloxane resin, compared with the case of using a conductive resin composition containing 33.3% by mass or more of an epoxy resin as a resin component, an electronic component with high moisture resistance can be manufactured.

[0200] (Example 14)

[0201] A paste composition was obtained in the same manner as in Example 4. The obtained paste composition was diluted with benzyl alcohol and adjusted to a viscosity of 30 Pa·s at 25°C and a shear rate of 4 (1 / s).

[0202] Next, the thickness of the conductive resin composition cast onto the PET film was adjusted so that the film thickness of the cured film was as shown in Table 3. Except for this, the moisture permeability was evaluated in the same manner as above. The results are shown in Table 3 and Figure 3 as shown.

[0203] (Comparative Example 5)

[0204] Metal powder 1, metal powder 2, epoxy resin 1, butyral resin 1, benzyl alcohol, and boron trifluoride monoethylamine (manufactured by Stella-Chemifa Co., Ltd.) were mixed in a ratio of 40:60:9:9:31:0.4 (mass ratio) (the ratio of epoxy resin and butyral resin as resin solid components), and then kneaded using a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd.) to obtain a paste composition. The obtained paste composition was diluted with benzyl alcohol and adjusted to a viscosity of 30 Pa·s at 25°C and a shear rate of 4 (1 / s).

[0205] Next, except for making the film thickness as shown in Table 3, the moisture permeability was evaluated in the same manner as above. The results are shown in Table 3 and Figure 3 as shown.

[0206] [Table 3]

[0207]

[0208] (Examples 15 to 26)

[0209] 135 parts by mass of polysiloxane resin 1 as a resin solid component was mixed with 165 parts by mass of benzyl alcohol (manufactured by GODO Co., Ltd.), and solvent replacement was carried out under the conditions of 130°C, 30 Pa, and 1 hour to obtain a resin solution. The obtained resin solution, metal powder 1, metal powder 2, silica powder 1, and benzyl alcohol were mixed in the ratios described in Tables 5 and 6, and then kneaded using a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd.) to obtain a paste composition.

[0210] The obtained composition was diluted with benzyl alcohol to adjust its viscosity to 4 Pa·s at 25°C and a shear rate of 4 (1 / s), and then the evaluation was carried out. The results are shown in Tables 5 and 6.

[0211] (Examples 27 to 31)

[0212] 135 parts by mass of polysiloxane resin 1 as a resin solid component was mixed with 165 parts by mass of benzyl alcohol (manufactured by GODO Co., Ltd.), and solvent replacement was carried out under the conditions of 130°C, 30 Pa, and 1 hour to obtain a resin solution. The obtained resin solution, metal powder 1, and metal powder 2 were mixed in the proportions shown in Table 7, and then kneaded using a three-roll mill (manufactured by Inoue Seisakusho) to obtain a paste-like composition.

[0213] The obtained composition was diluted with benzyl alcohol to adjust its viscosity to 40 Pa·s at 25°C and a shear rate of 4 (1 / s), and then the evaluation was carried out. The results are shown in Table 7.

[0214] (Examples 32 to 34, Comparative Example 6)

[0215] 135 parts by mass of polysiloxane resin 1 as a resin solid component was mixed with 165 parts by mass of benzyl alcohol (manufactured by GODO Co., Ltd.), and solvent replacement was carried out under the conditions of 130°C, 30 Pa, and 1 hour to obtain a resin solution. The obtained resin solution, metal powder 1, metal powder 2, and epoxy resin 1 were mixed in the proportions shown in Table 2, and then kneaded using a three-roll mill (manufactured by Inoue Seisakusho) to obtain a paste-like composition.

[0216] The obtained composition was diluted with benzyl alcohol to adjust its viscosity to 30 Pa·s at 25°C and a shear rate of 4 (1 / s), and then the evaluation was carried out. The results are shown in Table 8.

[0217] (Coatability Evaluation 1)

[0218] (Manufacture of a laminated electronic component)

[0219] As an electrode forming body, a laminated body was prepared, which was a substantially rectangular parallelepiped with a length of 3.2 mm, a width of 2.5 mm, and a height of 2.5 mm, Figure 1 as shown, and was formed by laminating a dielectric layer containing barium titanate and an internal electrode layer containing nickel in multiple layers.

[0220] On both end faces of the laminated body, with the longitudinal direction being the vertical direction, a conductive resin composition containing copper powder was coated by an impregnation method, and then held at 150°C for 10 minutes in an air atmosphere. Then, in a nitrogen atmosphere, the temperature was raised to 780°C at a heating rate of 50°C / minute, and after reaching 780°C, it was held for 15 minutes to form copper terminals.

[0221] On the copper terminals formed on both end faces of the laminate, with the longitudinal direction being the vertical direction, the conductive resin composition described in Table 4 or Table 8 is coated by the dipping method and held for 60 minutes under the conditions of an air atmosphere and 200 °C to cure the coated conductive resin composition, thereby forming a conductive resin layer on the copper terminals.

[0222] Furthermore, a nickel plating layer is formed on the conductive resin layer, and a tin plating layer is formed on the nickel plating layer to prepare a multilayer ceramic capacitor as a multilayer electronic component.

[0223] <Evaluation of manufacturability>

[0224] The cross-section of the multilayer electronic component in the vertical direction is observed by SEM, and the thickness of the conductive resin layer at the corner of the end face of the laminate (end face corner thickness) and the thickness of the conductive resin layer at the end face part of the laminate (end face thickness) are measured. At the corner of the laminate, the length of the part with the shortest distance from the boundary between the plating layer and the conductive resin layer to the boundary between the conductive resin layer and the base layer (copper terminal) is taken as the end face corner thickness. In addition, at the end face part of the laminate, the length of the part with the longest distance from the boundary between the conductive resin layer and the plating layer to the boundary between the conductive resin layer and the base layer (copper terminal) when a perpendicular line is drawn towards the laminate is taken as the end face thickness. Those with an end face corner thickness less than 2.5 μm and / or an end face thickness exceeding 300 μm are evaluated as "Score: 1, unqualified, unusable, poor manufacturability", those with an end face corner thickness of 5.0 μm or more and an end face thickness of 200 μm or less are evaluated as "Score: 3, qualified, usable, excellent manufacturability", and those other than these are evaluated as "Score: 2, qualified, usable, good manufacturability". The evaluation results of the shape of the conductive resin layer are shown in Table 4 or Table 8.

[0225] (Coatability evaluation 2)

[0226] <Manufacture of solid electrolytic capacitor>

[0227] As an electrode forming body, a formed cathode body is prepared, which is approximately cuboid with a length of 0.5 mm, a width of 3.7 mm, and a height of 5.4 mm, and contains an anode made of tantalum and a dielectric layer made of tantalum pentoxide formed on the anode surface.

[0228] A solid electrolyte layer is formed on the formed cathode body. After a carbon layer is formed on the solid electrolyte layer, with the height direction being the vertical direction, the conductive resin composition described in Table 5 or Table 6 is coated on the carbon layer by the dipping method and held for 60 minutes under the conditions of an air atmosphere and 170 °C to cure the coated conductive resin composition and form a conductive resin layer.

[0229] Then, it is connected to the terminal, and a resin outer layer is formed by the resin molding method to prepare a tantalum capacitor as a solid electrolytic capacitor.

[0230] <Evaluation of manufacturability>

[0231] The horizontal cross-section of the solid electrolytic capacitor is observed by SEM, and the thickness of the conductive resin layer at the corner of the side surface of the formed cathode body (side corner thickness) and the thickness of the conductive resin layer at the side surface of the formed cathode body (side thickness) are measured. At the corner of the formed cathode body, the length of the part with the shortest distance from the boundary between the resin outer layer and the conductive resin layer to the boundary between the conductive resin layer and the base layer (formed cathode body) is taken as the side corner thickness. In addition, at the side surface of the formed cathode body, the length of the part with the longest distance from the boundary between the resin outer layer and the conductive resin layer to the boundary between the conductive resin layer and the base layer (formed cathode body) is taken as the side thickness. Those with a side corner thickness of 5 μm or more and a side thickness of 20 μm or less are evaluated as "Score: 3, Pass, Usable, Excellent manufacturability", those with a side corner thickness less than 2.5 μm and / or a side thickness exceeding 40 μm are evaluated as "Score: 1, Fail, Unusable, Poor manufacturability", and those other than these are evaluated as "Score: 2, Pass, Usable, Good manufacturability". The evaluation results of the shape of the conductive resin layer are shown in Table 5 or Table 6.

[0232] (Coatability evaluation 3)

[0233] <Forming the conductive resin layer by screen printing>

[0234] Prepare an alumina substrate (1 inch square). On this substrate, the conductive composition described in Table 7 is screen printed with a line width of 150 μm and kept at 200 °C for 60 minutes in an air atmosphere to cure the printed conductive composition and form a conductive resin layer.

[0235] <Evaluation of the shape of the conductive resin layer>

[0236] After forming the conductive resin layer, those with no observed exudation, abrasion and good shape are evaluated as "Score: 3, Pass, Usable, Excellent formability", those with some observed exudation and abrasion but at a usable level are evaluated as "Score: 2, Pass, Usable", and those with obvious exudation, abrasion and at a non-usable level are evaluated as "Score: 1, Fail, Unusable, Poor formability". The evaluation results of the shape of the conductive resin layer are shown in Table 7.

[0237] [Table 4]

[0238]

[0239] [Table 5]

[0240]

[0241] [Table 6]

[0242]

[0243] [Table 7]

[0244]

[0245] [Table 8]

[0246]

Claims

1. A conductive resin composition containing metal powder, a resin binder, and an organic solvent, wherein 20.0 mass% or more of the metal powder is flaky metal powder, 70.0 mass% or more of the resin binder is a polysiloxane resin, the polysiloxane resin is a thermosetting polysiloxane resin, the conductive resin composition satisfies at least one of the following (1) and (2), (1) The polysiloxane resin is a polysiloxane resin having hydroxyl groups and cured by heating without using a curing agent; or a polysiloxane resin having hydroxyl groups and cured by a dehydration condensation reaction upon heating, (2) The moisture permeability obtained by the following moisture permeability measurement test is 80.0 mg or less, <Moisture Permeability Measurement Test> The conductive resin composition is cast on a PET film to a thickness of 250 μm and cured under the conditions of 200 °C for 60 minutes. The obtained cured film is cut into a circle with a diameter of 7.5 mm and fixed with an adhesive in a manner that covers a 5 ml glass bottle containing 2 g of silica gel. The glass bottle is placed in a 750 ml container containing 100 ml of purified water in a state where the cured film does not come into contact with the purified water and sealed, and then left standing in a dryer set at 65 °C for 15 hours. Then, the moisture permeability is calculated by the following formula (1): Moisture permeability (weight increase) = weight of the glass bottle after being placed in the dryer - weight of the glass bottle before being placed in the dryer (1).

2. The conductive resin composition according to claim 1, wherein when a strain of 1% is applied at an angular frequency of 1 Hz to the conductive resin composition, the value of the phase difference δ between the strain and the stress generated by the strain is in the range of 32 to 88°.

3. The conductive resin composition according to claim 1, wherein the ratio of the viscosity of the conductive resin composition at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is in the range of 1.4 to 60.

0.

4. The conductive resin composition according to claim 1, wherein the polysiloxane resin has epoxy groups.

5. The conductive resin composition according to claim 1, wherein the content of the resin binder is 2.5 to 35.0 mass parts relative to 100.0 mass parts of the metal powder.

6. The conductive resin composition according to claim 1, wherein the aspect ratio of the flaky metal powder is 1.5 to 50.

0.

7. The conductive resin composition according to claim 1, wherein the number average particle size of the flaky metal powder measured using a scanning electron microscope (SEM) is 0.1 to 20.0 μm.

8. The conductive resin composition according to claim 1, wherein The specific surface area of the flaky metal powder is 0.5 to 5.0 m 2 / g.

9. The conductive resin composition according to claim 1, wherein the metal powder contains the flaky metal powder and spherical metal powder, the content ratio of the spherical metal powder relative to the total amount of the metal powder is 80.0 mass% or less, and the content of the flaky metal powder relative to the total amount of the metal powder is 20.0 mass% or more.

10. The conductive resin composition according to claim 9, wherein, The cumulative 50% particle size (D 50 ) based on the volume of the spherical metal powder is 0.01 to 7.0 μm.

11. The conductive resin composition according to claim 9, wherein, The specific surface area of the spherical metal powder is 0.2 to 3.0 m 2 / g.

12. The conductive resin composition according to claim 1, wherein, the metal powder is at least one powder selected from powders of one or more of silver, copper, nickel, palladium, platinum, gold, and aluminum, powders containing an alloy containing one or more of these, silver-coated copper powder, and silver-coated nickel powder.

13. The conductive resin composition according to claim 1, wherein, the metal powder is a powder containing silver and / or copper.

14. The conductive resin composition according to any one of claims 1 to 13, wherein, the conductive resin composition is used for forming an external electrode of a laminated electronic component.

15. The conductive resin composition according to any one of claims 1 to 13, wherein, the conductive resin composition is used for forming a cathode of a solid electrolytic capacitor.

16. The conductive resin composition according to any one of claims 1 to 13, wherein, the conductive resin composition is used for dip printing.

17. The conductive resin composition according to claim 1, which is a conductive resin composition containing a metal powder, a resin binder, and an organic solvent, wherein, when the metal powder is set to 100.0 parts by mass, the content of the resin binder is 5.0 to 25.0 parts by mass, 80.0 mass% or more of the resin binder is a polysiloxane resin, 20.0 mass% or more of the metal powder is a flaky metal powder, when a strain of 1% is applied to the conductive resin composition at an angular frequency of 1 Hz, the value of the phase difference δ between the strain and the stress generated by the strain is in the range of 45 to 87°, the ratio of the viscosity of the conductive resin composition at a shear rate of 0.4 (1 / s) to the viscosity at a shear rate of 40 (1 / s) is in the range of 1.5 to 20.0.

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