Patent US2855384A successfully refreshed from Google Patents.
US2855384A
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Process for producing linear polyureas
Assignee: Bayer AG
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Filing: 1955-05-20
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Granted: 1958-10-07
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Expires: 1975-05-20
Abstract
No abstract record available.
Inventors
- 👤 Lehmann Wolfgang
- 👤 Rinke Heinrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:53
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/32; C08G18/3225; C08G18/3253; C08G18/3259; C08G18/3265; Y; Y10; Y10S; Y10S528/00; Y10S528/906
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
44 words
A METHOD FOR MAKING A LINEAR POLYUREA WHICH COMPRISES REACTING IN SUBSTANTIALLY EQUAL MOLECULAR PROPORTIONS A DIAMINE CARBAMATE SALT AND AN ALKYLENE DIISOCYANATE AT A TEMPERATURE OF AT LEAST ABOUT 70*C., THE ONLY GROUPS OF SAID DIISOCYANATE REACTIVE WITH SAID SALT BEING ISOCYANETA GROUPS.
Claim 2
Independent Claim
44 words
A METHOD FOR MAKING A LINEAR POLYUREA WHICH COMPRISES REACTING IN SUBSTANTIALLY EQUAL MOLECULAR PROPORTIONS A DIAMINE CARBAMATE SALT AND AN ALKYLENE DIISOCYANATE AT A TEMPERATURE OF AT LEAST ABOUT 70*C., THE ONLY GROUPS OF SAID DIISOCYANATE REACTIVE WITH SAID SALT BEING ISOCYANETA GROUPS.
References Cited (Backward Citations)
US2292443A
Cited
DE838217C
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-10-06 | 1962-04-07 | 1962-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-10-06 | 1966-04-07 | 1966-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-10-06 | 1970-04-07 | 1970-10-07 | $7700.00 | Window Closed / Lapsed |