US2608561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making duroquinone
Assignee: Rauma Raahe Oy
•
Filing: 1950-05-24
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Granted: 1952-08-26
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Expires: 1970-05-24
Abstract
No abstract record available.
Inventors
- 👤 Monnberg Bror Ragnar Mathias
- 👤 Ora Alpo Johannas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:56
CPC Classifications
C; C07; C07C; C07C50/00; C07C50/02; C07C46/00; C07C46/02; C07C46/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
27 words
A METHOD OF PRODUCING DUROQUINONE IN WHICH PENTAMETHYLPHENOL IS OXIDIZED WITH SULPHURIC ACID AND A COMPOUND SELECTED FROM THE GROUP CONSISTING OF SODIUM DICHROMATE AND POTASSIUM DICHROMATE.
Claim 2
Independent Claim
27 words
A METHOD OF PRODUCING DUROQUINONE IN WHICH PENTAMETHYLPHENOL IS OXIDIZED WITH SULPHURIC ACID AND A COMPOUND SELECTED FROM THE GROUP CONSISTING OF SODIUM DICHROMATE AND POTASSIUM DICHROMATE.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-08-26 | 1956-02-25 | 1956-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-08-26 | 1960-02-25 | 1960-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-08-26 | 1964-02-25 | 1964-08-26 | $7700.00 | Window Closed / Lapsed |