US2872302A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Etchant
Assignee: GTE Sylvania Inc
•
Filing: 1957-09-12
•
Granted: 1959-02-03
•
Expires: 1977-09-12
Abstract
No abstract record available.
Inventors
- 👤 Edward P Bulan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:01
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
A COPPER ETCHANT SOLUTION COMPRISING, IN AQQUEOUS SOLUTION, FERRIC NITRATE HAVING A CONCENTRATION BY WEIGHT FALLING WITHIN THE RANGE 20-100 GRAMS PER LITER; CHROMIC ACID 75-125 GRAMS PER LITER; AND SULPHURIC ACID, THE RANGE 75-125 GRAMS PER LITER; AND SULPHURIC ACID, THE RATIO OF CHROMIC ACID TP SULPHURIC ACID AS EXPRESSED IN CONCENTRATIONS BY WEIGHT BEING ABOUT 4 TO 1.
Claim 2
Dependent Claim
60 words
A COPPER ETCHANT SOLUTION COMPRISING, IN AQQUEOUS SOLUTION, FERRIC NITRATE HAVING A CONCENTRATION BY WEIGHT FALLING WITHIN THE RANGE 20-100 GRAMS PER LITER; CHROMIC ACID 75-125 GRAMS PER LITER; AND SULPHURIC ACID, THE RANGE 75-125 GRAMS PER LITER; AND SULPHURIC ACID, THE RATIO OF CHROMIC ACID TP SULPHURIC ACID AS EXPRESSED IN CONCENTRATIONS BY WEIGHT BEING ABOUT 4 TO 1.
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) | 1962-02-02 | 1962-08-04 | 1963-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-02-02 | 1966-08-04 | 1967-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-02-02 | 1970-08-04 | 1971-02-03 | $7700.00 | Window Closed / Lapsed |