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US2819308A Expired / Lapsed US ⏱️ 0.0 years remaining

Vitamin a-active material

Assignee: Nopco Chemical Co
•
Filing: 1955-11-04
•
Granted: 1958-01-07
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Expires: 1975-11-04
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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 16:35
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)

CA471786A Cited
US2415834A Cited
US2483347A Cited
US2507802A Cited
US2583194A Cited
US2744137A Cited
US2736746A Cited

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

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