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Patent US2878286A successfully refreshed from Google Patents.
US2878286A
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Process for preparing symmetrical hexachlorodiphenyl urea
Assignee: EIDP Inc
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Filing: 1945-06-09
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Granted: 1959-03-17
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Expires: 1965-06-09
Abstract
No abstract record available.
Inventors
- 👤 Ralph S Temple
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:10
CPC Classifications
C; C07; C07C; C07C273/00; C07C273/18; C07C273/1854; C07C273/1863
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
IN THE METHOD OF PREPARING SYMMETRICAL HEXACHLORODIPHENYL UREA BY REACTING A SUBSTANCE SELECTED FROM THE GROUP WHICH CONSISTS OF 2,4,6-TRICHLOROANILINE AND THE HYDROCHLORIDE THEREOF WITH UREA IN A REACTION MEDIUM AND WHEREIN SULFURIC ACID IS FED TO THE REACTION MIXTURE DURING THE COURSE OF THE REACTION, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE REACTION IN AN ACETIC ACID MEDIUM CONTAINING 1% TO 3% BY WEIGHT OF WATER.
Claim 2
Dependent Claim
67 words
IN THE METHOD OF PREPARING SYMMETRICAL HEXACHLORODIPHENYL UREA BY REACTING A SUBSTANCE SELECTED FROM THE GROUP WHICH CONSISTS OF 2,4,6-TRICHLOROANILINE AND THE HYDROCHLORIDE THEREOF WITH UREA IN A REACTION MEDIUM AND WHEREIN SULFURIC ACID IS FED TO THE REACTION MIXTURE DURING THE COURSE OF THE REACTION, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE REACTION IN AN ACETIC ACID MEDIUM CONTAINING 1% TO 3% BY WEIGHT OF WATER.
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) | 1962-03-16 | 1962-09-15 | 1963-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-16 | 1966-09-15 | 1967-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-16 | 1970-09-15 | 1971-03-17 | $7700.00 | Window Closed / Lapsed |