Electrolytic capacitor and its manufacturing method

Abstract

An electrolytic capacitor includes a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material disposed between the positive and the negative electrode, an electrolyte, a case for accommodating the capacitor element and the electrolyte, and a sealing member disposed to cover the opening of the case. The solid organic conductive material has at least one material selected from organic semiconductor and conductive polymer. The electrolytic capacitor having excellent impedance characteristic, small current leak, excellent reliability, and high dielectric strength.

What is claimed is: 
     
       1. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material, said capacitor element arranged such that said positive electrode and negative electrode define a region therebetween, 
 (b) an electrolyte, 
 (c) a case for accommodating said capacitor element and said electrolyte, and 
 (d) a sealing member disposed to over an opening of said case,
 wherein said solid organic conductive material is disposed so that said solid organic conductive material fills said region between said positive electrode and said negative electrode such that said solid organic conductive material functions as a solid electrolyte. 
 
 
     
     
       2. An electrolytic capacitor of  claim 1 , wherein said positive electrode comprises a metal foil and a dielectric oxide film formed on the surface of said metal foil, and has a valve action. 
     
     
       3. An electrolytic capacitor of  claim 1 , wherein said case is formed of a tubular metal having a bottom. 
     
     
       4. An The electrolytic capacitor of  claim 1 , wherein said solid organic conductive material has a conductive polymer. 
     
     
       5. An The electrolytic capacitor of  claim 4 , wherein said conductive polymer has a polymer of at least one monomer selected from the group consisting of pyrrole, aniline, thiophen, ethylene dioxythiophen, sulfonated aniline, sulfonated pyrrole, sulfonated thiophen, sulfonated ethylene dioxythiophen, and their derivatives. 
     
     
       6. An The electrolytic capacitor of  claim 4 , wherein said conductive polymer has at least one polymer selected from the group consisting of liquid-phase chemical polymerization composition, vapor-phase polymerization composition, liquid-phase electrolytic polymerization composition, and residual dry polymer of soluble polymer solution. 
     
     
       7. An The electrolytic capacitor of  claim 5 , wherein said conductive polymer has at least one polymer formed by chemically polymerizing selected from the group consisting of polypyrrole, polyethylene dioxythiophen, and polyaniline. 
     
     
       8. An The electrolytic capacitor of  claim 5 , wherein said conductive polymer has at least one polymer formed by electrolytically polymerizing selected from the group consisting of polypyrrole, polyethylene dioxythiophen, and polyaniline. 
     
     
       9. An The electrolytic capacitor of  claim 1 , wherein said solid organic conductive material is at least one selected from the group consisting of organic semiconductor and conductive polymer, and a residual dry polymer of soluble sulfonated polyaniline solution. 
     
     
       10. An The electrolytic capacitor of  claim 1 , wherein said electrolyte has an organic solvent, and at least one electrolytic substance of organic salt and inorganic salt dissolved in said organic solvent. 
     
     
       11. An The electrolytic capacitor of  claim 10 , wherein said solid organic conductive material is swollen in said organic solvent. 
     
     
       12. An The electrolytic capacitor of  claim 10 , wherein said electrolyte has at least one selected from the group consisting of a compound having alkyl subsistent amidine group, quaternary salt of compound having alkyl substituent amidine group, tertiary amine, and ammonium. 
     
     
       13. An The electrolytic capacitor of  claim 12 , wherein said electrolyte has said quaternary salt of compound having alkyl substituent amidine group, the alkyl substituent of said quaternary salt of compound having alkyl substituent amidine group is one selected from the group consisting of alkyl group and aryl alkyl group with 1 to 11 carbon atoms, and the compound having the amidine group of said quaternary salt of the compound having alkyl substituent amidine group is at least one selected from the group consisting of imidazole compound, benzoimidazole compound, and alicyclic amidine compound. 
     
     
       14. An The electrolytic capacitor of  claim 10 , wherein said electrolyte has at least one property selected from the group consisting of:
 (1) a boiling point is 200° C. or more, 
 (2) an electric conductivity at measuring temperature of 30° C. is 1.0 mS/cm or more, and 
 (3) a spark ignition voltage is 80 V or more. 
 
     
     
       15. The electrolytic capacitor of  claim 1 , wherein said solid organic conductive material is disposed on at least one of said positive electrode and said negative electrode. 
     
     
       16. The electrolytic capacitor of  claim 1 , wherein said solid organic conductive material is disposed at least one of in and on said separator, and further, said solid organic conductive material is disposed on at least one of said positive electrode and said negative electrode. 
     
     
       17. The electrolytic capacitor of  claim 1 , wherein said electrolyte includes a solvent and an electrolytic substance, and said electrolytic substance is dissolved in said solvent. 
     
     
       18. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material, said capacitor element arranged such that said positive electrode and negative electrode define a region therebetween,   (b) an electrolyte,   (c) a case for accommodating said capacitor element and said electrolyte, and   (d) a sealing member disposed to cover an opening of said case,
 wherein said solid organic conductive material is disposed so that said solid organic conductive material fills said region between said positive electrode and said negative electrode such that said solid organic conductive material functions as a solid electrolyte, wherein said solid organic conductive material has an organic semiconductor material. 
   
     
     
       19. An electrolytic capacitor of  claim 18 , wherein said organic semiconductor material is at least one selected from the group consisting of 7,7,8,8-tetracyanoquinodimethane complex and its derivatives. 
     
     
       20. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material disposed between said positive electrode and said negative electrode, 
 (b) an electrolyte, 
 (c) a case for accommodating said capacitor element and said electrolyte, and 
 (d) a sealing member disposed to cover an opening of said case,
 wherein said solid organic conductive material has an organic semiconductor material and a conductive polymer. 
 
 
     
     
       21. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material, said capacitor element arranged such that said positive electrode and negative electrode define a region therebetween, 
 (b) an electrolyte, 
 (c) a case for accommodating said capacitor element and said electrolyte, and 
 (d) a sealing member disposed to cover an opening of said case,
 wherein said solid organic conductive material is disposed so that said solid organic conductive material fills said region between said positive electrode and said negative electrode such that said solid organic conductive material functions as a solid electrolyte, wherein said solid organic conductive material has a conductive polymer, wherein said conductive polymer has a residual dry polymer of soluble sulfonated polyaniline solution. 
 
 
     
     
       22. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material disposed between said positive electrode and said negative electrode, 
 (b) an electrolyte, 
 (c) a case for accommodating said capacitor element and said electrolyte, and 
 (d) a sealing member disposed to cover an opening of said case,
 wherein said electrolyte has an organic solvent, and at least one electrolytic substance of organic salt and inorganic salt dissolved in said organic solvent, and  
 wherein a base of said at least one electrolytic substance has a hydrogen ion concentration of 1.0×10 −13  mol/dm 3  or more in 1 wt. % aqueous solution of the base or hydroxide of the base. 
 
 
     
     
       23. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material disposed between said positive electrode and said negative electrode, 
 (b) an electrolyte, 
 (c) a case for accommodating said capacitor element and said electrolyte, and 
 (d) a sealing member disposed to cover an opening of said case
 wherein said electrolyte has an organic solvent, and at least one electrolytic substance of organic salt and inorganic salt dissolved in said organic solvent, and  
 wherein said electrolyte has at least a quaternary salt of the compound having alkyl substituent amidine group selected from the group consisting of:
 1-methyl-1, 8-diazabicyclo [5,4,0] undecenc-7, 
 1-methyl-1, 5-diazabicyclo [4,3,0] nonene-5, 
 1,2,3-trimethyl imidazolinium, 
 1,2,3,4-tetramethyl imidazolinium, 
 1,2-dimethyl-3-ethyl-imidazolinium, 
 1,3,4-trimethyl-2-ethyl imidazolinium, 
 1,3-dimethyl-2-heptyl imidazolinium, 
 1,3-dimethyl-2-(-3′ heptyl) imidazolinium, 
 1,3-dimethyl-2-dodecyl imidazolinium, 
 1,2,3-trimethyl-1,4,5,6-tetrahydropyrimidium, 
 1,3-dimethyl imidazolium, 
 1-methyl-3-ethyl-imidazolium, and 
 1,3-dimethyl benzoimidazolium. 
 
 
 
     
     
       24. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material, said capacitor element arranged such that said positive electrode and negative electrode define a region therebetween, 
 (b) an electrolyte, 
 (c) a case for accommodating said capacitor element and said electrolyte, and 
 (d) a sealing member disposed to cover an opening of said case,
 wherein said solid organic conductive material is disposed so that said solid organic conductive material fills said region between said positive electrode and said negative electrode such that said solid organic conductive material functions as a solid electrolyte, said electrolytic capacitor further comprising a separator between said positive electrode and said negative electrodes, and wherein said solid organic conductive material is disposed on surfaces of said positive electrode and said negative electrode, and in said separator, said electrolyte includes a solvent and electrolytic substance, and said electrolyte is disposed in said solid organic conductive material and said separator at a state of swelling said solid organic conductive material and said separator. 
 
 
     
     
       25. An electrolytic capacitor comprising:
 (a) a capacitor clement having a positive electrode, a negative electrode, and a solid organic conductive material disposed between said positive electrode and said negative electrode,   (b) an electrolyte, and   (c) a case for accommodating said capacitor element and said electrolyte, wherein said solid organic conductive material is formed on at least one of said positive electrode and said negative electrode, wherein at least one of said positive electrode and said negative electrode has a dielectric oxide film formed on a surface thereof, wherein said dielectric oxide film has a roughening surface, and said solid organic conductive material is disposed in a hollow place of said roughening surface of said dielectric oxide film.   
     
     
       26. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material disposed between said positive electrode and said negative electrode, 
 (b) an electrolyte, and 
 (c) a case for accommodating said capacitor element and said electrolyte,
 wherein said solid organic conductive material is formed on at least one of said positive electrode and said negative electrode, and 
 
 said solid organic conductive material has at least one polymer selected from the group consisting of polythiophen, polyethylene dioxythiophen, and their derivatives. 
 
     
     
       27. The electrolytic capacitor of  claim 26 , further comprising a separator disposed between said positive electrode and said negative electrode. 
     
     
       28. The electrolytic capacitor of  claim 26 , wherein said electrolyte is disposed between said positive electrode and said negative electrode. 
     
     
       29. The electrolytic capacitor of  claim 26 , wherein said solid organic conductive material has at least one of an organic semiconductor material and a conductive polymer. 
     
     
       30. The electrolytic capacitor of  claim 26 , further comprising a sealing member disposed at an opening of said case. 
     
     
       31. The electrolytic capacitor of  claim 26 , wherein at least one of said positive electrode and said negative electrode has a dielectric oxide film formed on a surface thereof. 
     
     
       32. The electrolytic capacitor of  claim 26 , wherein said solid organic conductive material has a function of a solid electrolyte. 
     
     
       33. The electrolytic capacitor of  claim 26 , wherein said electrolyte includes a solvent and electrolytic substance, and said electrolytic substance is dissolved in said solvent. 
     
     
       34. The electrolytic capacitor of  claim 26 , wherein said solid organic conductive material is disposed so that said solid organic conductive material fills between said positive electrode and said negative electrode formed by impregnating between said positive electrode and said negative electrode with a liquid composition that includes said solid organic conductive material and a solvent, and by drying said liquid composition thereafter. 
     
     
       35. The electrolytic capacitor of  claim 26 , further comprising a separator between said positive electrode and said negative electrode, wherein said solid organic conductive material is disposed further in said separator, said electrolyte includes a solvent and electrolytic substance, and said electrolyte is disposed in said solid organic conductive material and said separator at a state of swelling said solid organic conductive material and said separator. 
     
     
       36. An electrolytic capacitor comprising:
 (a) a capacitor element having a positive electrode, a negative electrode, and a solid organic conductive material disposed between said positive electrode and said negative electrode, 
 (b) a separator disposed between said positive electrode and said negative electrode, 
 (c) an electrolyte, and 
 (d) a case for accommodating said capacitor element and said electrolyte,
 wherein said solid organic conductive material is disposed at least one of in and on said separator, and 
 further said solid organic conductive material is disposed on at least one of said positive electrode and said negative electrode, and 
 
 said electrolyte swells said solid organic conductive material. 
 
     
     
       37. The electrolytic capacitor of  claim 36 , wherein said electrolyte is disposed between said positive electrode and said negative electrode has at least one of γ-butyrolactone and ethylene glycol. 
     
     
       38. The electrolytic capacitor of  claim 36 , wherein said solid organic conductive material has at least one of an organic semiconductor material and a conductive polymer polymer selected from the group consisting of polythiophen, polyethylene dioxythiophen, and their derivatives. 
     
     
       39. The electrolytic capacitor of  claim 36 , further comprising a sealing member disposed at an opening of said case. 
     
     
       40. The electrolytic capacitor of  claim 36 , wherein at least one of said positive electrode and said negative electrode has a dielectric oxide film formed on a surface thereof. 
     
     
       41. The electrolytic capacitor of  claim 40 , wherein said dielectric oxide film has a roughening surface, and said solid organic conductive material is disposed in a hollow place of said roughening surface of said dielectric oxide film. 
     
     
       42. The electrolytic capacitor of  claim 36 , wherein said solid organic conductive material has a function of a solid electrolyte. 
     
     
       43. The electrolytic capacitor of  claim 36 , wherein said electrolyte includes a solvent and electrolytic substance, and said electrolytic substance is dissolved in said solvent. 
     
     
       44. The electrolytic capacitor of  claim 36 , wherein said solid organic conductive material is disposed so that said solid organic conductive material fills between said positive electrode and said negative electrode formed by impregnating between said positive electrode and said negative electrode with a liquid composition that includes said solid organic conductive material and a solvent, and by drying said liquid composition thereafter. 
     
     
       45. The electrolytic capacitor of  claim 36 , wherein said solid organic conductive material is disposed in said separator, said electrolyte includes a solvent and electrolytic substance, and said electrolyte is disposed in said solid organic conductive material and said separator at a state of swelling said solid organic conductive material and said separator. 
     
     
       46. The electrolytic capacitor of claim 5, wherein said conductive polymer has at least one polymer selected from the group consisting of polythiophen, polyethylene dioxythiophen, and their derivatives.  
     
     
       47. The electrolytic capacitor of claim 10, wherein said organic solvent has at least one of γ-butyrolactone and ethylene glycol.  
     
     
       48. The electrolytic capacitor of claim 10, wherein said electrolyte has at least one selected from the group consisting of polyhydric alcohol system solvents, lactone system solvents, water, amide system solvents, ether system solvents, nitrile system solvents, furane system solvents, and 2-imidazolidinone system solvents.  
     
     
       49. The electrolytic capacitor of claim 10, wherein said electrolyte has at least one selected from the group consisting of phosphor compounds, boric acid compounds, and nitro compounds.  
     
     
       50. The electrolytic capacitor of claim 33, wherein said organic solvent has at least one of γ-butyrolactone and ethylene glycol.  
     
     
       51. The electrolytic capacitor of claim 33, wherein said electrolyte has at least one selected from the group consisting of polyhydric alcohol system solvents, lactone system solvents, water, amide system solvents, ether system solvents, nitrile system solvents, furane system solvents, and 2-imidazolidinone system solvents.  
     
     
       52. The electrolytic capacitor of claim 33, wherein said electrolyte has at least one selected from the group consisting of phosphor compounds, boric acid compounds, and nitro compounds.  
     
     
       53. The electrolytic capacitor of claim 36, wherein said electrolyte has at least one selected from the group consisting of polyhydric alcohol system solvents, lactone system solvents, water, amide system solvents, ether system solvents, nitrile system solvents, furane system solvents, and 2-imidazolidinone system solvents.  
     
     
       54. The electrolytic capacitor of claim 36, wherein said electrolyte has at least one selected from the group consisting of phosphor compounds, boric acid compounds, and nitro compounds.