Conductive resin composition
A method for manufacturing an electronic component includes: a preparation step of preparing an electrode-forming body for electronic components; and an electrode forming step of forming an electrode on an outer surface of the electrode-forming body for electronic components, wherein in the electrode forming step, a conductive resin layer is formed on the electrode-forming body for electronic components by using a conductive resin composition containing a metal powder, a resin binder, and an organic solvent, wherein 20.0% by mass or more of the metal powder is a flaky metal powder, and 70.0% by mass or more of the resin binder is a silicone resin. According to the present invention, it is possible to provide a method for manufacturing an electronic component having reduced restrictions on design and manufacturing and high manufacturing efficiency, in addition to high moisture resistance.
1 . A conductive resin composition, comprising a metal powder, a resin binder, and an organic solvent,
wherein 20.0% by mass or more of the metal powder is a flaky metal powder, and 70.0% by mass or more of the resin binder is a silicone resin, wherein the silicone resin is a thermosetting silicone resin, wherein the thermosetting silicone resin has a hydroxy group and an epoxy group, and is cured by heating without using a curing agent, and a content of the resin binder is 2.5 to 35.0 parts by mass with respect to 100.0 parts by mass of the metal powder; and
wherein when 1% strain is applied to the conductive resin composition at an angular frequency of 1 Hz, a value of a phase difference δ between the strain and a stress caused by the strain is in a range of 32 to 87° and/or a ratio of a viscosity of the conductive resin composition at a shear rate of 0.4 (1/s) to a viscosity thereof at a shear rate of 40 (1/s) is in a range of 1.5 to 60.0.
2 . The conductive resin composition according to claim 1 , wherein the silicone resin is cured through a dehydration reaction upon heating.
3 . The conductive resin composition according to claim 1 , wherein the flaky metal powder has an aspect ratio of 1.5 to 50.0.
4 . The conductive resin composition according to claim 1 , wherein the flaky metal powder has a number average particle diameter of 0.1 to 20.0 μm as measured using a scanning electron microscope (SEM).
5 . The conductive resin composition according to claim 1 , wherein the flaky metal powder has a specific surface area of 0.5 to 5.0 m 2 /g.
6 . The conductive resin composition according to claim 1 , wherein the metal powder is at least one or more powders selected from: one or more powders of silver, copper, nickel, palladium, platinum, gold, and aluminum; a powder containing an alloy of one or more of these metals; a silver-coated copper powder; and a silver-coated nickel powder.
7 . The conductive resin composition according to claim 1 , wherein the metal powder is a powder containing silver and/or copper.
8 . The conductive resin composition according to claim 1 , which is for forming an external electrode of a multilayer electronic component or a cathode of a solid electrolytic capacitor.
9 . The conductive resin composition according to claim 1 , wherein:
the content of the resin binder is 5.0 to 25.0 parts by mass with respect to 100.0 parts by mass of the metal powder;
80.0% by mass or more of the resin binder is a silicone resin;
when the 1% strain is applied to the conductive resin composition at the angular frequency of 1 Hz, the value of a phase difference δ between the strain and the stress caused by the strain is in a range of 45 to 87°; and
the ratio of a viscosity of the conductive resin composition at a shear rate of 0.4 (1/s) to a viscosity thereof at a shear rate of 40 (1/s) is in a range of 1.5 to 20.0.
10 . The conductive resin composition according to claim 1 , wherein
the flaky metal powder has an aspect ratio of 1.5 to 50.0,
the flaky metal powder has a number average particle diameter of 0.1 to 20.0 μm as measured using a scanning electron microscope (SEM), and
the flaky metal powder has a specific surface area of 0.5 to 5.0 m 2 /g.
11 . The conductive resin composition according to claim 1 , wherein
the flaky metal powder has an aspect ratio of 1.5 to 50.0,
the flaky metal powder has a number average particle diameter of 0.1 to 20.0 μm as measured using a scanning electron microscope (SEM), and
the flaky metal powder has a specific surface area of 0.5 to 5.0 m 2 /g.
12 . The conductive resin composition according to claim 1 , wherein
the flaky metal powder has an aspect ratio of 1.5 to 50.0,
the flaky metal powder has a number average particle diameter of 0.1 to 20.0 μm as measured using a scanning electron microscope (SEM), and
the flaky metal powder has a specific surface area of 0.5 to 5.0 m 2 /g.
13 . The conductive resin composition according to claim 6 , wherein
the flaky metal powder has an aspect ratio of 1.5 to 50.0,
the flaky metal powder has a number average particle diameter of 0.1 to 20.0 μm as measured using a scanning electron microscope (SEM), and
the flaky metal powder has a specific surface area of 0.5 to 5.0 m 2 /g.
14 . The conductive resin composition according to claim 2 , wherein
the flaky metal powder has an aspect ratio of 1.5 to 50.0,
the flaky metal powder has a number average particle diameter of 0.1 to 20.0 μm as measured using a scanning electron microscope (SEM), and
the flaky metal powder has a specific surface area of 0.5 to 5.0 m 2 /g.
15 . The conductive resin composition according to claim 1 , wherein a moisture permeation amount is 80.0 mg or less as determined in a moisture permeation amount measurement test by:
casting the conductive resin composition on a PET film to a thickness of 250 μm and curing the conductive resin composition at 200° C. for 60 minutes to form a cured film;
cutting the cured film into a circle of 7.5 mm in diameter and fixing the circle with an adhesive so as to cover a 5 ml glass bottle containing 2 g of silica gel;
placing the glass bottle in a 750 ml vessel containing 100 ml of purified water so that the cured film does not come into contact with the purified water;
sealing the vessel and placing the vessel in a dryer at 65° C. for 15 hours; and
calculating the moisture permeation amount by the following equation (1):
moisture permeation amount (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).