Etch solutions having bis(perfluoroalkylsulfonyl)imides, and use thereof to form anode foils with increased capacitance

Patent metadata

Field	Value
Publication number	US-10072349-B2
Application number	US-201614988548-A
Country	US
Kind code	B2
Filing date	Jan 5, 2016
Priority date	Jan 5, 2016
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a sulfate, a halide, an oxidizing agent, and a surface active agent. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath. The etched anode foil is suitable for use in an electrolytic capacitor.

First claim

What is claimed is:

1. An electrolyte bath composition for etching anode foil, comprising:
a sulfate;
a halide;
an oxidizing agent;
and a bis(perfluoroalkylsulfonyl)imide;
in an aqueous solvent,
wherein the bis(perfluoroalkylsulfonyl)imide is a bis(perfluoroethylsulfonyl)imide present in an amount ranging from about 10 to about 20 ppm.

2. The composition of claim 1 , wherein the sulfate is provided by a salt or acid selected from the group consisting of sodium sulfate, potassium sulfate, lithium sulfate, sulfuric acid, and mixtures thereof.

3. The composition of claim 1 , wherein the halide is provided by a salt or acid selected from the group consisting of sodium chloride, titanium (III) chloride, hydrochloric acid, and any mixture thereof.

4. The composition of claim 1 , wherein the sulfate is provided by sulfuric acid.

5. The composition of claim 4 , wherein the sulfuric acid is present at about 0.92 weight percent.

6. The composition of claim 1 , wherein the ratio of halide to oxidizing agent is about 2:1.

7. The composition of claim 1 , wherein the bis(perfluoroalkylsulfonyl)imide is provided as an alkali metal salt or an ammonium salt.

8. The composition of claim 7 , wherein the salt of the bis(perfluoroalkylsolfonyl)imide is a sodium, potassium, lithium, or ammonium salt.

9. The composition of claim 1 wherein the halide is provided by hydrochloric acid.

10. The composition of claim 9 , wherein the hydrochloric acid is added at about 0.62 weight percent.

11. The composition of claim 1 , wherein the oxidizing agent is provided by sodium perchlorate added at about 3.5 weight percent.

12. The composition of claim 1 , wherein the bis(perfluoroalkylsulfonyl)imide is provided as an alkali metal salt or an ammonium salt.

13. The composition of claim 11 , wherein the salt of the bis(perfluoroalkylsulfonyl)imide is a sodium, potassium, lithium, or ammonium salt.

Assignees

• Pacesetter Inc

Inventors

• Jiang Xiaofei
• Stocker Tearl
• Geiculescu A Corina
• Hemphill Ralph Jason

Classifications

• C25F3/02 Primary

  Etching · CPC title