Patent US3167463A successfully refreshed from Google Patents.
US3167463A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of burning in photoresists and then etching
Assignee: MASTER ETEHING MACHINE Co
•
Filing: 1961-11-22
•
Granted: 1965-01-26
•
Expires: 1981-11-22
Abstract
No abstract record available.
Inventors
- 👤 Robert J Patsko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:35
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/02; G; G03; G03F; G03F7/00; G03F7/26; G03F7/40; H; H05; H05K; H05K3/00; H05K3/02; H05K3/06; H05K3/061; H05K3/064
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
100 words
THE METHOD OF ETCHING METALLIC WORK COATED WITH A PHOTORESIST OF THE CLASS CONSISTING OF BICHROMATED SHELLAC AND BICHROMATED POLYVINYL ALCOHOL, WHICH COMPRISES IMMERSING THE METALLIC WORK COATED WITH A PHOTORESIST OF THE CLASS CONSISTING OF BICHROMATED SHELLAC AND BICHROMATED POLYVINYL ALCOHOL IN A MOLTEN SALT BATH CONSISTING OF FROM 30 TO 60% OF A NITRATE OF A CLASS CONSISTING OF SODIUM NITRATE AND POTASSIUM NITRATE AND FROM 40% TO 70% OF SODIUM NITRITE, MAINTAINED AT A TEMPERATURE BETWEEN 300 AND 450*F. TO BURN IN THE PHOTORESIST, AND SUBSEQUENTLY ETCHING THE METALLIC WORK WHILE IT IS PROTECTED BY SAID PHOTORESIST.
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) | 1968-01-26 | 1968-07-27 | 1969-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-01-26 | 1972-07-27 | 1973-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-01-26 | 1976-07-27 | 1977-01-26 | $7700.00 | Window Closed / Lapsed |