Polymerization solution, conductive polymer film obtained from the polymerization solution, and solid electrolytic capacitor

Patent metadata

Field	Value
Publication number	US-9558891-B2
Application number	US-201214002281-A
Country	US
Kind code	B2
Filing date	Mar 1, 2012
Priority date	Mar 1, 2011
Publication date	Jan 31, 2017
Grant date	Jan 31, 2017

Abstract

Disclosed is a polymerization solution for electrolytic polymerization containing borodisalicylic acid and/or a salt thereof as a supporting electrolyte, in which precipitation due to the hydrolysis of borodisalicylate ions is inhibited and which provides a conductive polymer exhibiting excellent heat resistance. The polymerization solution has: a solvent consisting of 100 to 80% by mass of water and 0 to 20% by mass of an organic solvent; at least one monomer having a π-conjugated double bond; at least one supporting electrolyte selected from the group consisting of borodisalicylic acid and borodisalicylic salts; and at least one stabilizing agent selected from the group consisting of nitrobenzene and nitrobenzene derivatives, and the content of the stabilizing agent content is more than ⅛ mol per 1 mol of the supporting electrolyte. A complex is formed by the stabilizing agent and borodisalicylic acid, and the formation of precipitation due to the hydrolysis of borodisalicylate ions is inhibited.

First claim

What is claimed is:

1. A polymerization solution for electrolytic polymerization of monomer having a π-conjugated double bond, comprising:
a solvent consisting of 100 to 80% by mass of water and 0 to 20% by mass of an organic solvent;
at least one monomer having a π-conjugated double bond;
at least one supporting electrolyte selected from the group consisting of borodisalicylic acid and borodisalicylic salts; and
at least one stabilizing agent selected from the group consisting of nitrobenzene and nitrobenzene derivatives, wherein the content of the stabilizing agent is more than ⅛ mol per 1 mol of the supporting electrolyte.

2. The polymerization solution according to claim 1 , wherein the stabilizing agent is at least one compound selected from the group consisting of o-nitrophenol, m-nitrophenol and p-nitrophenol.

3. The polymerization solution according to claim 1 , wherein the solvent consists only of water.

4. The polymerization solution according to claim 1 , wherein the stabilizing agent is p-nitrophenol and the content of p-nitrophenol is ¼ mol or more per 1 mol of the supporting electrolyte.

5. The polymerization solution according to claim 1 , wherein the monomer is 3,4-ethylenedioxythiophene.

6. The polymerization solution according to claim 1 , further comprising at least one nonionic surfactant.

7. The polymerization solution according to claim 6 , wherein the nonionic surfactant is a mixture of an alkynediol and a polyoxyethylene alkylphenyl ether.

8. The polymerization solution according to claim 1 , wherein the monomer is dispersed as oil drops in the polymerization solution.

9. A conductive polymer film obtained by introducing a substrate with a conductive part at least on the surface in the polymerization solution according to claim 1 and then performing electrolytic polymerization.

10. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface; and
a conductive polymer layer on the positive electrode, wherein the conductive polymer layer is formed by introducing the positive electrode in the polymerization solution according to claim 1 and then performing electrolytic polymerization.

11. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface,
a negative electrode made of valve metal foil; and
a separator retaining an conductive polymer layer between the positive electrode and the negative electrode, wherein the conductive polymer layer is formed by introducing in the polymerization solution according to claim 1 a capacitor element comprising the positive electrode, the negative electrode and a separator therebetween, impregnating the polymerization solution in the capacitor element and then performing electrolytic polymerization.

12. A conductive polymer film obtained by introducing a substrate with a conductive part at least on the surface in the polymerization solution according to claim 3 and then performing electrolytic polymerization.

13. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface; and
a conductive polymer layer on the positive electrode, wherein the conductive polymer layer is formed by introducing the positive electrode in the polymerization solution according to claim 3 and then performing electrolytic polymerization.

14. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface,
a negative electrode made of valve metal foil; and
a separator retaining an conductive polymer layer between the positive electrode and the negative electrode, wherein the conductive polymer layer is formed by introducing in the polymerization solution according to claim 3 a capacitor element comprising the positive electrode, the negative electrode and a separator therebetween, impregnating the polymerization solution in the capacitor element and then performing electrolytic polymerization.

15. A conductive polymer film obtained by introducing a substrate with a conductive part at least on the surface in the polymerization solution according to claim 5 and then performing electrolytic polymerization.

16. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface; and
a conductive polymer layer on the positive electrode, wherein the conductive polymer layer is formed by introducing the positive electrode in the polymerization solution according to claim 5 and then performing electrolytic polymerization.

17. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface,
a negative electrode made of valve metal foil; and
a separator retaining an conductive polymer layer between the positive electrode and the negative electrode, wherein the conductive polymer layer is formed by introducing in the polymerization solution according to claim 5 a capacitor element comprising the positive electrode, the negative electrode and a separator therebetween, impregnating the polymerization solution in the capacitor element and then performing electrolytic polymerization.

18. A conductive polymer film obtained by introducing a substrate with a conductive part at least on the surface in the polymerization solution according to claim 7 and then performing electrolytic polymerization.

19. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface; and
a conductive polymer layer on the positive electrode, wherein the conductive polymer layer is formed by introducing the positive electrode in the polymerization solution according to claim 7 and then performing electrolytic polymerization.

20. A solid electrolytic capacitor comprising:
a positive electrode made of valve metal foil with an oxide film on the surface,
a negative electrode made of valve metal foil; and
a separator retaining an conductive polymer layer between the positive electrode and the negative electrode, wherein the conductive polymer layer is formed by introducing in the polymerization solution according to claim 7 a capacitor element comprising the positive electrode, the negative electrode and a separator therebetween, impregnating the polymerization solution in the capacitor element and then performing electrolytic polymerization.

Assignees

• Machida Kenji
• Takeda Sekihiro
• Muroi Ryo
• Kamiyama Nozomu
• Ozawa Masashi
• Nippon Chemicon

Inventors

• Machida Kenji
• Takeda Sekihiro
• Muroi Ryo
• Kamiyama Nozomu
• Ozawa Masashi

Classifications

• H01G9/0036

  Formation of the solid electrolyte layer · CPC title

• H01G9/15

  Solid electrolytic capacitors (H01G11/00 takes precedence) · CPC title

• C08G2261/51

  Charge transport · CPC title

• C08G2261/3223

  containing one or more sulfur atoms as the only heteroatom, e.g. thiophene · CPC title

• H01G9/028 Primary

  Organic semiconducting electrolytes, e.g. TCNQ · CPC title