Thermosetting conductive resin composition and method for producing electronic component
Provided is a thermosetting conductive resin composition including: a conductive powder including a base metal; a thermosetting silicone resin having hydroxyl groups; and at least one of an amine-based additive and an acid-based additive. According to the present invention, a thermosetting conductive resin composition for forming electrodes of electronic components can be provided that has high viscosity stability and can form a conductive resin layer having a reduced decrease in conductivity (excellent conductivity) and excellent moisture resistance, even when the thermosetting silicone resin having hydroxyl groups and the conductive powder including a base metal such as Cu are included.
1 . A thermosetting conductive resin composition comprising:
a conductive powder including a base metal;
a resin binder comprising at least a thermosetting silicone resin having hydroxyl groups and being curable by heating without using a curing agent or a catalyst; and
at least one of an amine-based additive and an acid-based additive, wherein a content of the resin binder is 3.0 parts by mass or more and 30.0 parts by mass or less relative to 100 parts by mass of the conductive powder, and the thermosetting conductive resin composition satisfies at least one of the following (1) and (2):
(1) a content of the amine-based additive is 0.3 parts by mass or more and 20.0 parts by mass or less relative to 100 parts by mass of the thermosetting silicone resin having the hydroxyl groups and being curable by heating without using the curing agent or the catalyst, and/or a content of the acid-based additive is 0.05 parts by mass or more and 3.2 parts by mass or less relative to 100 parts by mass of the conductive powder including the base metal, and
(2) the content of the amine-based additive is 0.05 parts by mass or more and 3.2 parts by mass or less relative to 100 parts by mass of the conductive powder including the base metal.
2 . The thermosetting conductive resin composition according to claim 1 , wherein a molecular weight of the amine-based additive or the acid-based additive is 30 or more and 2,000 or less.
3 . The thermosetting conductive resin composition according to claim 1 , wherein a boiling point Tb under 1 atm or a temperature Td90 at 90% by mass reduction of the amine-based additive or the acid-based additive is 80° C. or more and 400° C. or less.
4 . The thermosetting conductive resin composition according to claim 1 , wherein the amine-based additive comprises at least one of a secondary amine and a tertiary amine.
5 . The thermosetting conductive resin composition according to claim 1 , wherein the acid-based additive comprises a dicarboxylic acid.
6 . The thermosetting conductive resin composition according to claim 1 , satisfying at least one of the following (1′) and (2′),
(1′) a content of the amine-based additive is 0.6 parts by mass or more and 10.0 parts by mass or less relative to 100 parts by mass of the thermosetting silicone resin having hydroxyl groups and being curable by heating without using the curing agent or the catalyst, and/or a content of the acid-based additive is 0.1 parts by mass to 1.6 parts by mass relative to 100 parts by mass of the conductive powder including the base metal, and
(2′) the content of the amine-based additive is 0.1 parts by mass or more and 1.6 parts by mass or less relative to 100 parts by mass of the conductive powder including the base metal.
7 . The thermosetting conductive resin composition according to claim 1 , wherein the thermosetting silicone resin having hydroxyl groups and being curable by heating without using a curing agent or a catalyst is a dehydration condensation-type thermosetting silicone resin having hydroxyl groups and being curable by a dehydration condensation reaction that proceeds by heating without using a curing agent or a catalyst.
8 . The thermosetting conductive resin composition according to claim 1 for forming an external electrode of multilayer electronic components or for forming a cathode of solid electrolytic capacitors.
9 . The thermosetting conductive resin composition according to claim 1 , further comprising an organic solvent.
10 . The thermosetting conductive resin composition according to claim 1 , further comprising a resin binder other than the thermosetting silicone resin having hydroxyl groups and being curable by heating without using a curing agent or a catalyst.
11 . The thermosetting conductive resin composition according to claim 1 , comprising the amine-based additive, wherein the base metal is Cu.
12 . The thermosetting conductive resin composition according to claim 1 being curable by heating at a heating temperature in the range of 150° C. to 300° C.
13 . The thermosetting conductive resin composition according to claim 1 having 80.0 mg or less of a moisture permeability amount as determined casting the thermosetting conductive resin composition on a PET film to a thickness of 250 μm to obtain a cast composition, curing the cast composition at 200° C. for 60 minutes to obtain a cured film, cutting the cured film into a circular shape having a diameter of 7.5 mm, fixing the cured film 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 container containing 100 ml of purified water so that the cured film does not come in contact with the purified water, sealing and placing the 750 ml container in a dryer at 65° C. for 15 hours, measuring a weight of the glass bottle before and after the glass bottle is placed in the dryer, and calculating the moisture permeability amount by subtracting the weight of the glass bottle before being placed in the dryer from the weight of the glass bottle after being placed in the dryer.
14 . A method for producing an electronic component, the method comprising:
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
a conductive resin layer is formed on the electrode-forming body for electronic components by applying the thermosetting conductive resin composition according to claim 1 onto the electrode-forming body for electronic components and subsequently curing the thermosetting conductive resin composition in the electrode forming step.
15 . The method for producing an electronic component according to claim 14 , wherein the thermosetting conductive resin composition is curable by heating at a heating temperature in the range of 150° C. to 300° C.