Back to results
US 10,309,033 B2Granted
Process additives to reduce etch resist undercutting in the manufacture of anode foils
AssigneePacesetter, Inc.
InventorsRalph Jason Hemphill, Timothy R. Marshall, Thomas F. Strange
Life of this patent
Estimating the term…
Abstract
Anode foil, preferably aluminum anode foil, is etched using a process of adding an etch resist to the anode foil and treating the foil in an electrolyte bath composition comprising a sulfate, a halide, an oxidizing agent, a surface active agent, and a non-ionic surfactant. 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.
Claims20
An aqueous electrolyte bath composition for etching anode foil, comprising:
- a sulfate;
- a halide;
- an oxidizing agent;
- a surface active agent selected from the group consisting of a bis(perfluoroalkylsulfonyl)imide, a perfluoroalkylsulfonate, and a mixture thereof;
- and
- a non-ionic surfactant, wherein the non-ionic surfactant is:
- present in an amount ranging from about 0.01 parts per million (ppm) to about 4 ppm,
- surface active at a pH level from about 1 to about 7,
- surface active at temperatures from about 0° C. to about 100° C., and
- water-soluble.
7 more elements
A method of etching an anode foil, comprising:
- adding an etch resist onto an anode foil;
- passing a direct current (DC) charge through the anode foil while the foil is immersed in an aqueous electrolyte bath, wherein said aqueous electrolyte bath composition comprises:
- a sulfate;
- a halide;
- an oxidizing agent;
- a surface active agent selected from the group consisting of a bis(perfluoroalkylsulfonyl)imide, a perfluoroalkylsulfonate, and a mixture thereof;
- and
- a non-ionic surfactant, wherein the non-ionic surfactant is:
- present in an amount ranging from about 0.01 parts per million (ppm) to about 4 ppm,
- surface active at a pH level from about 1 to about 7,
- surface active at temperatures from about 0° C. to about 100° C., and
- water-soluble.
9 more elements
Dependencies are inferred from the claim text.