Patent US2681358A successfully refreshed from Google Patents.
US2681358A
Expired / Lapsed
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Process for preparing diisothiocyanates
Assignee: EIDP Inc
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Filing: 1952-05-10
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Granted: 1954-06-15
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Expires: 1972-05-10
Abstract
No abstract record available.
Inventors
- 👤 Walter V Wirth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:39
CPC Classifications
C; C07; C07C; C07C331/00; C07C331/16; C07C331/30
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
70 words
THE PROCESS OF PREPARING ORGANIC ARYL DIISOTHIOCYANATES WHICH COMPRISES REFLUXING IN PROPORTION FROM 1.25 TO 1.5 MOLS OF AN ARYL DIISOCYANATE WITH 1 MOL OF PHOSPHORUS PENTASULFIDE IN AN INERT SOLVENT BOILING BETWEEN ABOUT 140* AND 200* C., WHICH IS PRESENT IN AMOUNT BETWEEN 2 AND 4 TIMES THE WEIGHT OF ARYL DIISOCYANATE, COOLING THE REACTION MASS BELOW 100* C. AND SEPARATING THE RESULTING ARYL DIISOTHIOCYANATE FROM THE REACTION MASS.
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) | 1957-06-14 | 1957-12-14 | 1958-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-06-14 | 1961-12-14 | 1962-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-06-14 | 1965-12-14 | 1966-06-15 | $7700.00 | Window Closed / Lapsed |