US2816908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of ortho-phthalonitrile
Assignee: Individual
•
Filing: 1956-06-29
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Granted: 1957-12-17
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Expires: 1976-06-29
Abstract
No abstract record available.
Inventors
- 👤 Robert S Aries
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:54
CPC Classifications
C; C07; C07C; C07C253/00; C07C253/24; C07C253/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
62 words
THE PROCESS FOR THE PREPARATION OF ORTHO-PHTHALONITRILE WHICH COMPRISES PASSING OVER A CATALYST FOR THE OXIDATION OF NAPHTHALENE TO PHTHALIC ANHYDRIDE AT A TEMPERATURE RANGING BETWEEN ABOUT 300*C, AND 600*C. A GASEOUS MIXTURE OF NAPHTHALENE, AT LEAST TWICE THE MOLAR AMOUNT OF AMMONIA AS OF NAPHTHALENE AND AT LEAST FOUR AND A HALF TIMES THE MOLAR AMOUNT OF OXYGEN AS OF NAPHTHALENE.
Claim 2
Dependent Claim
62 words
THE PROCESS FOR THE PREPARATION OF ORTHO-PHTHALONITRILE WHICH COMPRISES PASSING OVER A CATALYST FOR THE OXIDATION OF NAPHTHALENE TO PHTHALIC ANHYDRIDE AT A TEMPERATURE RANGING BETWEEN ABOUT 300*C, AND 600*C. A GASEOUS MIXTURE OF NAPHTHALENE, AT LEAST TWICE THE MOLAR AMOUNT OF AMMONIA AS OF NAPHTHALENE AND AT LEAST FOUR AND A HALF TIMES THE MOLAR AMOUNT OF OXYGEN AS OF NAPHTHALENE.
References Cited (Backward Citations)
US2203861A
Cited
US2499055A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-12-16 | 1961-06-17 | 1961-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-16 | 1965-06-17 | 1965-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-16 | 1969-06-17 | 1969-12-17 | $7700.00 | Window Closed / Lapsed |