US3663387A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of electrode foil for electrolytic capacitors
Assignee: Arcotronics Ltd
•
Filing: 1971-03-01
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Granted: 1972-05-16
•
Expires: 1991-03-01
Abstract
Abstract Very high gain etching of tantalum foil is achieved by effecting before electrolytic etching with an electrolyte containing lithium chloride, brushing of the surface of the foil with steel wool so as to produce local iron contamination of the tantalum.
Inventors
- 👤 Donald Keith Harrison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:54
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/004; H01G9/04; H01G9/048; H01G9/055; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12431; Y10T428/12493; Y10T428/12771; Y10T428/12806; Y10T428/12819
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
22 words
An etching process as claimed in claim 1 for the treatment of tantalum foil, wherein the brushing is effected with steel wool.
Claim 2
Dependent Claim
32 words
An etching process as claimed in claim 2, wherein the electrolytic etching is carried out with the use of an electrolyte constituted by a solution of lithium chloride in slightly diluted methanol.
Claim 3
Dependent Claim
38 words
An etching process as claimed in claim 2, wherein the electrolytic etching is carried out with the use of an electrolyte in which 20 gms per liter of lithium chloride are dissolved in 82.5 volume percent strength methanol.
Claim 4
Dependent Claim
21 words
Capacitor foil of film-forming material, whose effective surface has been increased by an electrolytic etching process as claimed in claim 1.
Claim 5
Dependent Claim
21 words
Capacitor foil of film-forming material, whose effective surface has been increased by an electrolytic etching process as claimed in claim 4.
Claim 6
Dependent Claim
18 words
A tantalum electrolytic capacitor having at least one electrode made of capacitor foil as claimed in claim 5.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |