US3184493A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of polyisocyanates
Assignee: Bayer AG
•
Filing: 1959-12-11
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Granted: 1965-05-18
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Expires: 1979-12-11
Abstract
No abstract record available.
Inventors
- 👤 Kunze Heinrich
- 👤 Bayer Otto
- 👤 Wehn Julius
- 👤 Siefken Werner
- 👤 Klauke Erich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:30
CPC Classifications
C; C08; C08L; C08L75/00; C08L75/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
A METHOD FOR CONVERTING A POLYUREA HAVING A MOLECULAR WEIGHT OF FROM ABOUT 300 TO 50,000 INTO AN ORGANIC POLYISOCYANATE WHICH COMPRISES SUSPENDING PARTICLES OF THE POLYUREA HAVING A PARTICLE SIZE OF FROM ABOUT 60 MICRONS TO ABOUT 500 MICRONS IN A FLUIDIZED BED OF INERT PARTICLES SUSPENDED IN A GAS CONTAINING PHOSGENE AT A TEMPERATURE OF ABOUT 100*C. TO ABOUT 300*C. WHEREBY A GAS CONTAINING AN ORGANIC POLYISOCYANATE IS OBTAINED, AND SEPARATING THE POLYISOCYANATE THEREFROM BY WASHING
Claim 2
Independent Claim
78 words
A METHOD FOR CONVERTING A POLYUREA HAVING A MOLECULAR WEIGHT OF FROM ABOUT 300 TO 50,000 INTO AN ORGANIC POLYISOCYANATE WHICH COMPRISES SUSPENDING PARTICLES OF THE POLYUREA HAVING A PARTICLE SIZE OF FROM ABOUT 60 MICRONS TO ABOUT 500 MICRONS IN A FLUIDIZED BED OF INERT PARTICLES SUSPENDED IN A GAS CONTAINING PHOSGENE AT A TEMPERATURE OF ABOUT 100*C. TO ABOUT 300*C. WHEREBY A GAS CONTAINING AN ORGANIC POLYISOCYANATE IS OBTAINED, AND SEPARATING THE POLYISOCYANATE THEREFROM BY WASHING
References Cited (Backward Citations)
DE946138C
Cited
US2689861A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-05-17 | 1968-11-16 | 1969-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-05-17 | 1972-11-16 | 1973-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-05-17 | 1976-11-16 | 1977-05-18 | $7700.00 | Window Closed / Lapsed |