Patent US2819308A successfully refreshed from Google Patents.
US2819308A
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Vitamin a-active material
Assignee: Nopco Chemical Co
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Filing: 1955-11-04
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Granted: 1958-01-07
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Expires: 1975-11-04
Abstract
No abstract record available.
Inventors
- 👤 Kurt H Schaaf
- 👤 Howard C Klein
- 👤 Kapp Roland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:46
CPC Classifications
C; C07; C07C; C07C403/00; C07C403/14; C07C403/18; C07C2601/00; C07C2601/12; C07C2601/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
A PROCESS FOR PRODUCING VITAMIN A ACTIVE MATERIAL WHICH COMPRISES THE STEPS OF REACTING AT A TEMPERATURE BETWEEN ABOUT ROOM TEMPERATURE AND 35*C. A BORON TRIBETWEEN ABOUT ROOM TEMPERATURE AND 35*C. A BORON TRIFLUORIDE HEXAMETHYLENE TETRAMINE COMPLEX CONTAINING AN AVERAGE OF ABOUT 1.5 TO ABOUT 2.5 MOLECULES OF BORON TRIFLUORIDE FOR EACH MOLECULE OF HEXAMETHYLENE TETRAMINE WITH AN ORGANIC COMPOUND HAVING THE STRUCTURAL FORMULA:
Claim 2
Dependent Claim
64 words
A PROCESS FOR PRODUCING VITAMIN A ACTIVE MATERIAL WHICH COMPRISES THE STEPS OF REACTING AT A TEMPERATURE BETWEEN ABOUT ROOM TEMPERATURE AND 35*C. A BORON TRIBETWEEN ABOUT ROOM TEMPERATURE AND 35*C. A BORON TRIFLUORIDE HEXAMETHYLENE TETRAMINE COMPLEX CONTAINING AN AVERAGE OF ABOUT 1.5 TO ABOUT 2.5 MOLECULES OF BORON TRIFLUORIDE FOR EACH MOLECULE OF HEXAMETHYLENE TETRAMINE WITH AN ORGANIC COMPOUND HAVING THE STRUCTURAL FORMULA:
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-06 | 1961-07-08 | 1962-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-06 | 1965-07-08 | 1966-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-06 | 1969-07-08 | 1970-01-07 | $7700.00 | Window Closed / Lapsed |