CN-122029623-A - Conductive paste, and laminated ceramic electronic component provided with external electrode formed using same

Abstract

A conductive paste comprising (A) conductive particles, (B) a thermosetting resin, and (C) rubber particles, wherein the (C) rubber particles comprise rubber particles whose main chain skeleton comprises carbon-carbon bonds and whose average particle diameter is less than 1 [ mu ] m. According to the present invention, a conductive paste having improved adhesion to a copper base material can be provided.

Inventors

• MATSUBARA MITSUAKI

Assignees

• 纳美仕有限公司

Dates

Publication Date

20260512

Application Date

20241115

Priority Date

20231117

Claims (14)

1. 1. A conductive paste comprising: a conductive particle, B thermosetting resin The particles of the C-type rubber, The C rubber particles comprise rubber particles whose main chain skeleton comprises carbon-carbon bonds and whose average particle diameter is less than 1 μm.
2. 2. The conductive paste of claim 1, wherein, The C rubber particles contain at least 1 selected from the group consisting of diene rubbers, (meth) acrylate rubbers, urethane rubbers, isoprene rubbers, fluorine rubbers, and chloroprene rubbers.
3. 3. The conductive paste according to claim 1 or 2, wherein, The C rubber particles comprise core-shell rubber particles.
4. 4. The conductive paste of claim 3, wherein, The core of the core-shell rubber particle is a rubber particle whose main chain skeleton contains carbon-carbon bonds.
5. 5. The conductive paste according to claim 3 or 4, wherein, The shell portion of the core-shell rubber particle is a shell portion comprising a polymer having a content of structural units having an epoxy group of 10 parts by mass or more.
6. 6. The conductive paste according to any one of claims 1 to 5, wherein, The amount of the C rubber particles is in the range of 0.1 to 10 parts by mass based on 100 parts by mass of the component A.
7. 7. The conductive paste according to any one of claims 1 to 6, wherein, The B thermosetting resin contains an epoxy resin, and the epoxy equivalent relative to the total mass of the thermosetting resin is 2000g/eq or less.
8. 8. The conductive paste according to any one of claims 1 to 7, wherein, The A contains spherical silver particles and flaky silver particles.
9. 9. The conductive paste according to any one of claims 1 to 8, wherein, The content of the component B is 3 to 25 parts by mass based on 100 parts by mass of the component A.
10. 10. The conductive paste according to any one of claims 1 to 9, wherein, After drying at 120 ℃ for 60 minutes, curing is performed by a blast dryer under the conditions of atmospheric air, 180 ℃ and 30 minutes, and the flexural modulus of elasticity at this time is 3GPa to 15GPa.
11. 11. The conductive paste according to any one of claims 1 to 9, wherein, After drying at 120℃for 60 minutes, the copper substrate was cured by a blow dryer under atmospheric conditions at 180℃for 30 minutes, and the adhesion strength to the copper substrate was 1.0kN/cm 2 or more.
12. 12. The conductive paste according to any one of claims 1 to 11, wherein, The thixotropic index value of the viscosity at a rotational speed of 10 rpm/viscosity at a rotational speed of 100rpm, which is measured at 25 ℃ by using an HB-type viscometer, is 7 or less.
13. 13. The conductive paste according to any one of claims 1 to 12, which is used for forming a 2 nd conductor layer of an external electrode having a1 st conductor layer connected to an internal electrode and a 2 nd conductor layer laminated on the 1 st conductor layer.
14. 14. A laminated ceramic electronic component comprising an external electrode formed using the conductive paste according to claim 13.

Description

Conductive paste, and laminated ceramic electronic component provided with external electrode formed using same Technical Field The present invention relates to a conductive paste and a laminated ceramic electronic component including an external electrode formed using the conductive paste. Background Chip-type laminated ceramic electronic components in which a plurality of dielectric layers and electrodes are laminated are used in a large number of electronic circuit applications in the field of electronic devices, particularly in small devices such as mobile phones and tablet terminals, in which cost reduction and miniaturization are strongly demanded. A conventional laminated ceramic electronic component will be described by taking a laminated ceramic capacitor shown in fig. 1 as an example. In a multilayer ceramic capacitor, an external electrode layer is provided instead of a lead wire, and thus a structure in which a plurality of dielectric layers and internal electrodes are stacked is reduced in size, which contributes significantly to the reduction in size and weight of electronic devices. The laminated ceramic capacitor 1 has a structure in which an external electrode layer 4 is provided on an internal electrode lead surface of a ceramic composite body formed by alternately laminating ceramic dielectrics 2 and internal electrode layers 3. Typically, the external electrode has a structure in which a plating treatment layer 5 is applied to the external electrode layer 4. The plating treatment layer 5 typically comprises a nickel plating layer and even further comprises a tin plating layer. When the laminated ceramic capacitor is mounted on the circuit board 7, the external electrode of the laminated ceramic capacitor and the wiring electrode of the circuit board are connected via the solder layer 6. As a cause of failure of an electronic circuit using the laminated ceramic capacitor, there are physical factors such as application of an external force to a circuit board on which the laminated ceramic capacitor is mounted, and occurrence of deflection in the circuit board. Such external force is transmitted to the laminated composite portion in the form of stress via the welded layer and the external electrode, and peeling of the external electrode from the ceramic composite and occurrence of cracks in the ceramic composite may occur. As a means for improving the reliability of an electronic circuit against a physical force from the outside, it has been proposed to provide an electrode layer as a buffer material on the external electrode layer 4 (patent document 1). In this method, a copper base material is used as the 1 st conductor layer 11 as an external electrode connected to the internal electrode of the multilayer capacitor, and a conductive paste containing a resin is used as the 2 nd conductor layer 12 as a buffer material thereon to be laminated, thereby forming an external electrode composed of a plurality of layers. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2011-233252 Disclosure of Invention Problems to be solved by the invention Since the conductive paste constituting the external electrode of the electronic component is required to have safety and high reliability, flexibility capable of withstanding the deflection of the substrate is required. As means for achieving this, a method as described in patent document 1 is used, but in the method described in patent document 1, adhesion between layers is required for providing a plurality of layers as external electrodes. When the conductive paste described in patent document 1 is used as the 2 nd conductor layer constituting one layer of the external electrode layer, there is still room for improvement in adhesion to the copper base material as the 1 st conductor layer. Accordingly, an object of the present invention is to provide a conductive paste having improved adhesion to a copper base material. Means for solving the problems The present inventors have repeatedly conducted intensive studies in order to solve the above-mentioned problems, and have finally completed the present invention. That is, the present invention is not limited to the following, but includes the following. 1. A conductive paste comprising: (A) Conductive particles, (B) Thermosetting resin and process for producing the same (C) The rubber particles are used as a filler of the rubber, The rubber particles (C) include rubber particles having a main chain skeleton containing carbon-carbon bonds and an average particle diameter of less than 1 μm. 2. The conductive paste according to the item 1, wherein the (C) rubber particles contain at least 1 selected from the group consisting of diene rubbers, (meth) acrylate rubbers, urethane rubbers, isoprene rubbers, fluorine rubbers, and chloroprene rubbers. 3. The conductive paste according to the item 1 or 2, wherein the (C) rubber particles comprise core-shell rubber part