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CN-122029626-A - Solid electrolytic capacitor and method for manufacturing the same

CN122029626ACN 122029626 ACN122029626 ACN 122029626ACN-122029626-A

Abstract

A solid electrolytic capacitor comprising a porous body containing a valve metal, a dielectric layer formed on the surface of the porous body, and 2 or more conductive layers covering the dielectric layer, wherein the 2 or more conductive layers have a1 st conductive layer formed on the surface of the dielectric layer and a2 nd conductive layer laminated on the 1 st conductive layer, and the 2 nd conductive layer comprises a polyaniline complex doped with polyaniline by a proton donor.

Inventors

  • ONODERA SHINGO
  • FUJII NOZOMI
  • Board float

Assignees

  • 出光兴产株式会社

Dates

Publication Date
20260512
Application Date
20241210
Priority Date
20231215

Claims (16)

  1. 1. A solid electrolytic capacitor comprising a porous body containing a valve metal, a dielectric layer formed on the surface of the porous body, and 2 or more conductive layers covering the dielectric layer, The above 2 or more conductive layers include a1 st conductive layer formed on the surface of the dielectric layer and a 2 nd conductive layer laminated on the 1 st conductive layer, The 2 nd conductive layer comprises a polyaniline complex doped with polyaniline using a proton donor.
  2. 2. The solid electrolytic capacitor of claim 1 wherein the dielectric layer comprises an oxide of the valve metal.
  3. 3. The solid electrolytic capacitor according to claim 1 or 2, wherein the polyaniline complex is doped with sulfosuccinic acid.
  4. 4. The solid electrolytic capacitor according to any one of claims 1 to 3, wherein the 2 nd conductive layer further comprises a thixotropic imparting agent.
  5. 5. The solid electrolytic capacitor according to claim 4, wherein the thixotropy imparting agent comprises inorganic particles.
  6. 6. The solid electrolytic capacitor according to claim 5, wherein the inorganic particles comprise 1 or more selected from the group consisting of silica, titania, alumina, and zirconia.
  7. 7. The solid electrolytic capacitor according to any one of claims 4 to 6, wherein the thixotropic agent has a content of 0.01 to 50 mass% relative to the entire 2 nd conductive layer.
  8. 8. The solid electrolytic capacitor according to any one of claims 1 to 7, wherein the 2 nd conductive layer further comprises a thickener.
  9. 9. The solid electrolytic capacitor according to claim 8, wherein the thickener is a polyether-based compound or a cellulose-based compound.
  10. 10. The solid electrolytic capacitor according to claim 8 or 9, wherein the content of the thickener with respect to the entire 2 nd conductive layer is 0.001 mass% to 5 mass%.
  11. 11. The solid electrolytic capacitor according to any one of claims 1 to 10, wherein the 2 nd conductive layer is formed of a conductive polymer composition satisfying the following conditions (P1) and (P2), (P1) the viscosity at a shear rate of 10 (1/s) is 1 Pa.s or more; (P2) after 30 seconds of shearing at a shearing speed of 10 (1/s), the viscosity immediately after the shearing at a shearing speed of 0.0001 (1/s) was 10 Pa.s or more and satisfied the following formula (P2-1), 。
  12. 12. The solid electrolytic capacitor according to any one of claims 1 to 11, wherein the valve metal is selected from the group consisting of aluminum, tantalum, niobium, titanium, hafnium, zirconium, zinc, tungsten, bismuth, and antimony.
  13. 13. A method for manufacturing a solid electrolytic capacitor, comprising the following steps (A-1) or (A-2), step (B) and step (C), A step (A-1) of immersing a part or the whole of the porous body having the valve metal oxide in a1 st electroconductive polymer composition containing an electroconductive polymer and a solvent; A step (A-2) of immersing a part or the whole of the porous body having the valve metal oxide in a1 st electroconductive polymer composition containing an electroconductive polymer, a solvent and a phenolic compound; a step (B) of taking out the porous body from the 1 st conductive polymer composition used in the step (A-1) or (A-2) and holding the porous body at a temperature equal to or lower than the boiling point of the solvent contained in the 1 st conductive polymer composition; And (C) immersing a part or the whole of the porous body after the step (B) in a2 nd conductive polymer composition containing a conductive polymer identical to or different from the 1 st conductive polymer composition, a thixotropic agent and a solvent, and drying the same.
  14. 14. The method for producing a solid electrolytic capacitor according to claim 13, wherein the thixotropic agent is contained in an amount of 0.2 to 5% by mass based on the entire 2 nd conductive polymer composition.
  15. 15. The method for manufacturing a solid electrolytic capacitor according to claim 13 or 14, wherein the 2 nd conductive polymer composition satisfies the following conditions (P1) and (P2): (P1) the viscosity at a shear rate of 10 (1/s) is 1 Pa.s or more; (P2) after 30 seconds of shearing at a shearing speed of 10 (1/s), the viscosity immediately after the shearing at a shearing speed of 0.0001 (1/s) was 10 Pa.s or more and satisfied the following formula (P2-1), 。
  16. 16. A solid electrolytic capacitor obtained by the method for producing a solid electrolytic capacitor according to any one of claims 13 to 15.

Description

Solid electrolytic capacitor and method for manufacturing the same Technical Field The present invention relates to a solid electrolytic capacitor and a method for manufacturing the same. Background In solid electrolytic capacitors such as aluminum electrolytic capacitors and tantalum capacitors, conductive polymers are used as materials for solid electrolyte layers. The outer layer of the solid electrolytic capacitor generally has a laminated structure of 3 layers, i.e., a conductive polymer layer, a carbon layer, and a silver paste layer. The charges stored inside the capacitor element are extracted to the outside through the layers. Patent document 1 discloses a tantalum capacitor (tantalum condenser) in which a conductive polymer layer, a carbon layer, and a silver layer are sequentially formed on a tantalum sintered body having a dielectric oxide layer (patent document 1). Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2023-99299 Disclosure of Invention However, the conventional structure disclosed in patent document 1 has a problem that the wet heat resistance of the tantalum capacitor is low and the usable environment is limited. Accordingly, the present inventors have conducted intensive studies and as a result, have found that a solid electrolytic capacitor excellent in wet heat resistance can be obtained by adopting a specific configuration for each layer of the solid electrolytic capacitor, and have completed the present invention. The present invention provides a solid electrolytic capacitor excellent in moist heat resistance and a method for manufacturing the same. According to the present invention, the following solid electrolytic capacitor and the like are provided. 1. A solid electrolytic capacitor comprising a porous body containing a valve metal, a dielectric layer formed on the surface of the porous body, and at least 2 conductive layers covering the dielectric layer, The 2 or more conductive layers include a 1 st conductive layer formed on the surface of the dielectric layer and a 2 nd conductive layer laminated on the 1 st conductive layer, The 2 nd conductive layer contains polyaniline complex doped with polyaniline using proton donor. 2. The solid electrolytic capacitor according to the above 1, wherein the dielectric layer contains an oxide of the valve metal. 3. The solid electrolytic capacitor according to the above 1 or 2, wherein the polyaniline complex is doped with sulfosuccinic acid. 4. The solid electrolytic capacitor according to any one of the above 1 to 3, wherein the 2 nd conductive layer further comprises a thixotropic agent. 5. The solid electrolytic capacitor according to the above 4, wherein the thixotropic agent contains inorganic particles. 6. The solid electrolytic capacitor according to the above 5, wherein the inorganic particles contain 1 or more kinds selected from the group consisting of silica, titania, alumina and zirconia. 7. The solid electrolytic capacitor according to any one of the above 4 to 6, wherein the thixotropic agent is contained in an amount of 0.01 to 50% by mass based on the entire 2 nd conductive layer. 8. The solid electrolytic capacitor according to any one of 1 to 7, wherein the 2 nd conductive layer further comprises a thickener. 9. The solid electrolytic capacitor according to the above 8, wherein the thickener is a polyether compound or a cellulose compound. 10. The solid electrolytic capacitor according to the item 8 or 9, wherein the content of the thickener in the entire 2 nd conductive layer is 0.001 to 5% by mass. 11. The solid electrolytic capacitor according to any one of the above 1 to 10, wherein the 2 nd conductive layer is formed of a conductive polymer composition satisfying the following conditions (P1) and (P2). (P1) the viscosity at a shear rate of 10 (1/s) is 1 Pa.s or more. (P2) after 30 seconds of shearing at a shearing speed of 10 (1/s), the viscosity immediately after the shearing at a shearing speed of 0.0001 (1/s) was 10 Pa.s or more, and the following formula (P2-1) was satisfied. [ Math 1] 12. The solid electrolytic capacitor according to any one of the above 1 to 11, wherein the valve metal is selected from the group consisting of aluminum, tantalum, niobium, titanium, hafnium, zirconium, zinc, tungsten, bismuth and antimony. 13. A method for manufacturing a solid electrolytic capacitor, comprising the following steps (A-1) or (A-2), step (B) and step (C). A step (A-1) of immersing a part or the whole of the porous body having the valve metal oxide in a1 st electroconductive polymer composition containing an electroconductive polymer and a solvent; A step (A-2) of immersing a part or the whole of the porous body having the valve metal oxide in a1 st electroconductive polymer composition containing an electroconductive polymer, a solvent and a phenolic compound; a step (B) of taking out the porous body from the 1 st conductive polymer composition used in the s